WorldWideScience

Sample records for plasma solar x-ray

  1. Solar X-ray bursts

    International Nuclear Information System (INIS)

    Urnov, A.M.

    1980-01-01

    In the popular form the consideration is given to the modern state tasks and results of X-ray spectrometry of solar bursts. The operation of X-ray spectroheliograph is described. Results of spectral and polarization measurings of X-ray radiation of one powerful solar burst are presented. The conclusion has been drawn that in the process of burst development three characteristic stages may be distingwished: 1) the initial phase; just in this period processes which lead to observed consequences-electromagnetic and corpuscular radiation are born; 2) the impulse phase, or the phase of maximum, is characterised by sharp increase of radiation flux. During this phase the main energy content emanates and some volumes of plasma warm up to high temperatures; 3) the phase of burst damping, during which plasma cools and reverts to the initial condition

  2. X-ray emitting hot plasma in solar active regions observed by the SphinX spectrometer

    Science.gov (United States)

    Miceli, M.; Reale, F.; Gburek, S.; Terzo, S.; Barbera, M.; Collura, A.; Sylwester, J.; Kowalinski, M.; Podgorski, P.; Gryciuk, M.

    2012-08-01

    Aims: The detection of very hot plasma in the quiescent corona is important for diagnosing heating mechanisms. The presence and the amount of such hot plasma is currently debated. The SphinX instrument on-board the CORONAS-PHOTON mission is sensitive to X-ray emission of energies well above 1 keV and provides the opportunity to detect the hot plasma component. Methods: We analysed the X-ray spectra of the solar corona collected by the SphinX spectrometer in May 2009 (when two active regions were present). We modelled the spectrum extracted from the whole Sun over a time window of 17 days in the 1.34-7 keV energy band by adopting the latest release of the APED database. Results: The SphinX broadband spectrum cannot be modelled by a single isothermal component of optically thin plasma and two components are necessary. In particular, the high statistical significance of the count rates and the accurate calibration of the spectrometer allowed us to detect a very hot component at ~7 million K with an emission measure of ~2.7 × 1044 cm-3. The X-ray emission from the hot plasma dominates the solar X-ray spectrum above 4 keV. We checked that this hot component is invariably present in both the high and low emission regimes, i.e. even excluding resolvable microflares. We also present and discuss the possibility of a non-thermal origin (which would be compatible with a weak contribution from thick-target bremsstrahlung) for this hard emission component. Conclusions: Our results support the nanoflare scenario and might confirm that a minor flaring activity is ever-present in the quiescent corona, as also inferred for the coronae of other stars.

  3. The X-ray signature of solar coronal mass

    Science.gov (United States)

    Harrison, R. A.; Waggett, P. W.; Bentley, R. D.; Phillips, K. J. H.; Bruner, M.

    1985-01-01

    The coronal response to six solar X-ray flares has been investigated. At a time coincident with the projected onset of the white-light coronal mass ejection associated with each flare, there is a small, discrete soft X-ray enhancement. These enhancements (precursors) precede by typically about 20 m the impulsive phase of the solar flare which is dominant by the time the coronal mass ejection has reached an altitude above 0.5 solar radii. Motions of hot X-ray emitting plasma, during the precursors, which may well be a signature of the mass ejection onsets, are identified. Further investigations have also revealed a second class of X-ray coronal transient, during the main phase of the flare. These appear to be associated with magnetic reconnection above post-flare loop systems.

  4. X-ray hot plasma diagnostics

    International Nuclear Information System (INIS)

    Cojocaru, E.

    1984-11-01

    X-ray plasma emission study is powerful diagnostic tool of hot plasmas. In this review article the main techniques of X-ray plasma emission measurement are shortly presented: X-ray spectrometry using absorbent filters, crystal and grating spectrometers, imaging techniques using pinhole cameras, X-ray microscopes and Fresnel zone plate cameras, X-ray plasma emission calorimetry. Advances in these techniques with examples for different hot plasma devices are also presentes. (author)

  5. X-ray Emission from Solar Flares

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... Solar flares; X-ray detectors; X-ray line emission and continuum; break energy; microflares. Abstract. Solar X-ray Spectrometer (SOXS), the first space-borne solar astronomy experiment of India was designed to improve our current understanding of X-ray emission from the Sun in general and solar flares in ...

  6. Imaging Plasma Density Structures in the Soft X-Rays Generated by Solar Wind Charge Exchange with Neutrals

    Science.gov (United States)

    Sibeck, David G.; Allen, R.; Aryan, H.; Bodewits, D.; Brandt, P.; Branduardi-Raymont, G.; Brown, G.; Carter, J. A.; Collado-Vega, Y. M.; Collier, M. R.; Connor, H. K.; Cravens, T. E.; Ezoe, Y.; Fok, M.-C.; Galeazzi, M.; Gutynska, O.; Holmström, M.; Hsieh, S.-Y.; Ishikawa, K.; Koutroumpa, D.; Kuntz, K. D.; Leutenegger, M.; Miyoshi, Y.; Porter, F. S.; Purucker, M. E.; Read, A. M.; Raeder, J.; Robertson, I. P.; Samsonov, A. A.; Sembay, S.; Snowden, S. L.; Thomas, N. E.; von Steiger, R.; Walsh, B. M.; Wing, S.

    2018-06-01

    Both heliophysics and planetary physics seek to understand the complex nature of the solar wind's interaction with solar system obstacles like Earth's magnetosphere, the ionospheres of Venus and Mars, and comets. Studies with this objective are frequently conducted with the help of single or multipoint in situ electromagnetic field and particle observations, guided by the predictions of both local and global numerical simulations, and placed in context by observations from far and extreme ultraviolet (FUV, EUV), hard X-ray, and energetic neutral atom imagers (ENA). Each proposed interaction mechanism (e.g., steady or transient magnetic reconnection, local or global magnetic reconnection, ion pick-up, or the Kelvin-Helmholtz instability) generates diagnostic plasma density structures. The significance of each mechanism to the overall interaction (as measured in terms of atmospheric/ionospheric loss at comets, Venus, and Mars or global magnetospheric/ionospheric convection at Earth) remains to be determined but can be evaluated on the basis of how often the density signatures that it generates are observed as a function of solar wind conditions. This paper reviews efforts to image the diagnostic plasma density structures in the soft (low energy, 0.1-2.0 keV) X-rays produced when high charge state solar wind ions exchange electrons with the exospheric neutrals surrounding solar system obstacles. The introduction notes that theory, local, and global simulations predict the characteristics of plasma boundaries such the bow shock and magnetopause (including location, density gradient, and motion) and regions such as the magnetosheath (including density and width) as a function of location, solar wind conditions, and the particular mechanism operating. In situ measurements confirm the existence of time- and spatial-dependent plasma density structures like the bow shock, magnetosheath, and magnetopause/ionopause at Venus, Mars, comets, and the Earth. However, in situ

  7. Early evolution of an X-ray emitting solar active region

    International Nuclear Information System (INIS)

    Wolfson, C.J.; Acton, L.W.; Leibacher, J.W.; Roethig, D.T.

    1977-01-01

    The birth and early evolution of a solar active region has been investigated using X-ray observations from the Lockheed Mapping X-Ray Heliometer on board the OSO-8 spacecraft. X-ray emission is observed within three hours of the first detection of Hα plage. At that time, a plasma temperature of 4 x 10 6 K in a region having a density of the order of 10 10 cm -3 is inferred. During the fifty hours following birth almost continuous flares or flare-like X-ray bursts are superimposed on a monotonically increasing base level of X-ray emission produced by plasma with a temperature of the order 3 x 10 6 K. If it is assumed that the X-rays result from heating due to dissipation of current systems or magnetic field reconnection, it can be concluded that flare-like X-ray emission soon after active region birth implies that the magnetic field probably emerges in a stressed or complex configuration. (Auth.)

  8. Coordinated soft X-ray and H-alpha observation of solar flares

    Science.gov (United States)

    Zarro, D. M.; Canfield, R. C.; Metcalf, T. R.; Lemen, J. R.

    1988-01-01

    Soft X-ray, Ca XIX, and H-alpha observations obtained for a set of four solar flares in the impulsive phase are analyzed. A blue asymmetry was observed in the coronal Ca XIX line during the soft-Xray rise phase in all of the events. A red asymmetry was observed simultaneously in chromospheric H-alpha at spatial locations associated with enhanced flare heating. It is shown that the impulsive phase momentum of upflowing soft X-ray plasma equalled that of the downflowing H-alpha plasma to within an order of magnitude. This supports the explosive chromospheric evaporation model of solar flares.

  9. The CubeSat Imaging X-ray Solar Spectrometer (CubIXSS) Mission Concept

    Science.gov (United States)

    Caspi, Amir; Shih, Albert Y.; Warren, Harry; DeForest, Craig; Laurent, Glenn Thomas; Schwartz, Richard A.; Woods, Thomas N.; Mason, James; Palo, Scott; Steslicki, Marek; Sylwester, Janusz; Gburek, Szymon; Mrozek, Tomasz; Kowalinski, Miroslaw; Torre, Gabriele; Crowley, Geoffrey; Schattenburg, Mark

    2017-08-01

    Solar soft X-ray (SXR) observations provide important diagnostics of plasma heating, during solar flares and quiescent times. Spectrally- and temporally-resolved measurements are crucial for understanding the dynamics, origins, and evolution of these energetic processes, providing probes both into the temperature distributions and elemental compositions of hot plasmas; spatially-resolved measurements are critical for understanding energy transport and mass flow. A better understanding of the thermal plasma improves our understanding of the relationships between particle acceleration, plasma heating, and the underlying release of magnetic energy during reconnection. We introduce a new proposed small satellite mission, the CubeSat Imaging X-ray Solar Spectrometer (CubIXSS), to measure spectrally- and spatially-resolved SXRs from the quiescent and flaring Sun from a 6U CubeSat platform in low-Earth orbit during a nominal 1-year mission. CubIXSS includes the Amptek X123-FastSDD silicon drift detector, a low-noise, commercial off-the-shelf (COTS) instrument enabling solar SXR spectroscopy from ~0.5 to ~30 keV with ~0.15 keV FWHM spectral resolution with low power, mass, and volume requirements. Multiple detectors and tailored apertures provide sensitivity to a wide range of solar conditions, optimized for a launch during solar minimum. The precise spectra from these instruments will provide detailed measurements of the coronal temperature distribution and elemental abundances from the quiet Sun to active regions and flares. CubIXSS also includes a novel spectro-spatial imager -- the first ever solar imager on a CubeSat -- utilizing a custom pinhole camera and Chandra-heritage X-ray transmission diffraction grating to provide spatially- resolved, full-Sun imaging spectroscopy from ~0.1 to ~10 keV, with ~25 arcsec and ~0.1 Å FWHM spatial and spectral resolutions, respectively. MOXSI’s unique capabilities enable SXR spectroscopy and temperature diagnostics of individual

  10. The soft x ray telescope for Solar-A

    Science.gov (United States)

    Brown, W. A.; Acton, L. W.; Bruner, M. E.; Lemen, J. R.; Strong, K. T.

    1989-01-01

    The Solar-A satellite being prepared by the Institute for Sapce and Astronautical Sciences (ISAS) in Japan is dedicated to high energy observations of solar flares. The Soft X Ray Telescope (SXT) is being prepared to provide filtered images in the 2 to 60 A interval. The flight model is now undergoing tests in the 1000 foot tunnel at MSFC. Launch will be in September 1991. Earlier resolution and efficiency tests on the grazing incidence mirror have established its performance in soft x rays. The one-piece, two mirror grazing incidence telescope is supported in a strain free mount separated from the focal plane assembly by a carbon-epoxy metering tube whose windings and filler are chosen to minimize thermal and hygroscopic effects. The CCD detector images both the x ray and the concentric visible light aspect telescope. Optical filters provide images at 4308 and 4700 A. The SXT will be capable of producing over 8000 of the smallest partial frame images per day, or fewer but larger images, up to 1024 x 1024 pixel images. Image sequence with two or more of the five x ray analysis filters, with automatic exposure compensation to optimize the charge collection by the CCD detector, will be used to provide plasma diagnostics. Calculations using a differential emission measure code were used to optimize filter selection over the range of emission measure variations and to avoid redundancy, but the filters were chosen primarily to give ratios that are monotonic in plasma temperature.

  11. The soft x ray telescope for Solar-A

    International Nuclear Information System (INIS)

    Brown, W.A.; Acton, L.W.; Bruner, M.E.; Lemen, J.R.; Strong, K.T.

    1989-01-01

    The Solar-A satellite being prepared by the Institute for Sapce and Astronautical Sciences (ISAS) in Japan is dedicated to high energy observations of solar flares. The Soft X Ray Telescope (SXT) is being prepared to provide filtered images in the 2 to 60 A interval. The flight model is now undergoing tests in the 1000 foot tunnel at MSFC. Launch will be in September 1991. Earlier resolution and efficiency tests on the grazing incidence mirror have established its performance in soft x rays. The one-piece, two mirror grazing incidence telescope is supported in a strain free mount separated from the focal plane assembly by a carbon-epoxy metering tube whose windings and filler are chosen to minimize thermal and hygroscopic effects. The CCD detector images both the x ray and the concentric visible light aspect telescope. Optical filters provide images at 4308 and 4700 A. The SXT will be capable of producing over 8000 of the smallest partial frame images per day, or fewer but larger images, up to 1024 x 1024 pixel images. Image sequence with two or more of the five x ray analysis filters, with automatic exposure compensation to optimize the charge collection by the CCD detector, will be used to provide plasma diagnostics. Calculations using a differential emission measure code were used to optimize filter selection over the range of emission measure variations and to avoid redundancy, but the filters were chosen primarily to give ratios that are monotonic in plasma temperature

  12. Properties of an impulsive compact solar flare determined from Solar Maximum Mission X-ray measurements

    Science.gov (United States)

    Linford, G. A.; Wolfson, C. J.

    1988-01-01

    Soft X-ray, hard X-ray magnetogram, and H-alpha data have been analyzed for an impulsive compact solar flare which occurred on May 21, 1985. The derived flare loop dimensions are about 20,000 km length and about 150 km diameter. Measurements of line ratios from the Mg XI ion indicate that the plasma density varied from about 4 x 10 to the 12th/cu cm early in the flare to about 10 to the 12th/cu cm during the flare decay. The initial temperature of this plasma was about 8 x 10 to the 6th K and dropped to about 5 x 10 to the 6th K during the decay phase. The simplest interpretation of the event is one in which the source of the soft X-ray flare emission is confined to a thin loop of very high density.

  13. Properties of an impulsive compact solar flare determined from Solar Maximum Mission X-ray measurements

    International Nuclear Information System (INIS)

    Linford, G.A.; Wolfson, C.J.

    1988-01-01

    Soft X-ray, hard X-ray magnetogram, and H-alpha data have been analyzed for an impulsive compact solar flare which occurred on May 21, 1985. The derived flare loop dimensions are about 20,000 km length and about 150 km diameter. Measurements of line ratios from the Mg XI ion indicate that the plasma density varied from about 4 x 10 to the 12th/cu cm early in the flare to about 10 to the 12th/cu cm during the flare decay. The initial temperature of this plasma was about 8 x 10 to the 6th K and dropped to about 5 x 10 to the 6th K during the decay phase. The simplest interpretation of the event is one in which the source of the soft X-ray flare emission is confined to a thin loop of very high density. 44 references

  14. Properties of an impulsive compact solar flare determined from Solar Maximum Mission X-ray measurements

    Energy Technology Data Exchange (ETDEWEB)

    Linford, G.A.; Wolfson, C.J.

    1988-08-01

    Soft X-ray, hard X-ray magnetogram, and H-alpha data have been analyzed for an impulsive compact solar flare which occurred on May 21, 1985. The derived flare loop dimensions are about 20,000 km length and about 150 km diameter. Measurements of line ratios from the Mg XI ion indicate that the plasma density varied from about 4 x 10 to the 12th/cu cm early in the flare to about 10 to the 12th/cu cm during the flare decay. The initial temperature of this plasma was about 8 x 10 to the 6th K and dropped to about 5 x 10 to the 6th K during the decay phase. The simplest interpretation of the event is one in which the source of the soft X-ray flare emission is confined to a thin loop of very high density. 44 references.

  15. SphinX: The Solar Photometer in X-Rays

    Science.gov (United States)

    Gburek, Szymon; Sylwester, Janusz; Kowalinski, Miroslaw; Bakala, Jaroslaw; Kordylewski, Zbigniew; Podgorski, Piotr; Plocieniak, Stefan; Siarkowski, Marek; Sylwester, Barbara; Trzebinski, Witold; Kuzin, Sergey V.; Pertsov, Andrey A.; Kotov, Yurij D.; Farnik, Frantisek; Reale, Fabio; Phillips, Kenneth J. H.

    2013-04-01

    Solar Photometer in X-rays (SphinX) was a spectrophotometer developed to observe the Sun in soft X-rays. The instrument observed in the energy range ≈ 1 - 15 keV with resolution ≈ 0.4 keV. SphinX was flown on the Russian CORONAS-PHOTON satellite placed inside the TESIS EUV and X telescope assembly. The spacecraft launch took place on 30 January 2009 at 13:30 UT at the Plesetsk Cosmodrome in Russia. The SphinX experiment mission began a couple of weeks later on 20 February 2009 when the first telemetry dumps were received. The mission ended nine months later on 29 November 2009 when data transmission was terminated. SphinX provided an excellent set of observations during very low solar activity. This was indeed the period in which solar activity dropped to the lowest level observed in X-rays ever. The SphinX instrument design, construction, and operation principle are described. Information on SphinX data repositories, dissemination methods, format, and calibration is given together with general recommendations for data users. Scientific research areas in which SphinX data find application are reviewed.

  16. Trends in NOAA Solar X-ray Imager Performance

    Science.gov (United States)

    Hill, Steven M.; Darnell, John A.; Seaton, Daniel B.

    2016-05-01

    NOAA has provided operational soft X-ray imaging of the sun since the early 2000’s. After 15 years of observations by four different telescopes, it is appropriate to examine the data in terms of providing consistent context for scientific missions. In particular, this presentation examines over 7 million GOES Solar X-ray Imager (SXI) images for trends in performance parameters including dark current, response degradation, and inter-calibration. Because observations from the instrument have overlapped not only with each other, but also with research observations like Yohkoh SXT and Hinode XRT, relative performance comparisons can be made. The first GOES Solar X-ray Imager was launched in 2001 and entered operations in 2003. The current SXIs will remain in operations until approximately 2020, when a new series of Solar (extreme-)Ultraviolet Imagers (SUVIs) will replace them as the current satellites reach their end of life. In the sense that the SXIs are similar to Yokoh’s SXT and Hinode’s XRT, the SUVI instruments will be similar to SOHO’s EIT and SDO’s AIA. The move to narrowband EUV imagers will better support eventual operational estimation of plasma conditions. While NOAA’s principal use of these observations is real-time space weather forecasting, they will continue to provide a reliable context measurement for researchers for decades to come.

  17. Laser plasma x-ray source for ultrafast time-resolved x-ray absorption spectroscopy

    Directory of Open Access Journals (Sweden)

    L. Miaja-Avila

    2015-03-01

    Full Text Available We describe a laser-driven x-ray plasma source designed for ultrafast x-ray absorption spectroscopy. The source is comprised of a 1 kHz, 20 W, femtosecond pulsed infrared laser and a water target. We present the x-ray spectra as a function of laser energy and pulse duration. Additionally, we investigate the plasma temperature and photon flux as we vary the laser energy. We obtain a 75 μm FWHM x-ray spot size, containing ∼106 photons/s, by focusing the produced x-rays with a polycapillary optic. Since the acquisition of x-ray absorption spectra requires the averaging of measurements from >107 laser pulses, we also present data on the source stability, including single pulse measurements of the x-ray yield and the x-ray spectral shape. In single pulse measurements, the x-ray flux has a measured standard deviation of 8%, where the laser pointing is the main cause of variability. Further, we show that the variability in x-ray spectral shape from single pulses is low, thus justifying the combining of x-rays obtained from different laser pulses into a single spectrum. Finally, we show a static x-ray absorption spectrum of a ferrioxalate solution as detected by a microcalorimeter array. Altogether, our results demonstrate that this water-jet based plasma source is a suitable candidate for laboratory-based time-resolved x-ray absorption spectroscopy experiments.

  18. SphinX MEASUREMENTS OF THE 2009 SOLAR MINIMUM X-RAY EMISSION

    OpenAIRE

    Sylwester, J.; Kowalinski, M.; Gburek, S.; Siarkowski, M.; Kuzin, S.; Farnik, F.; Reale, F.; Phillips, K. J. H.; Bakala, J.; Gryciuk, M.; Podgorski, P.; Sylwester, B.

    2012-01-01

    The SphinX X-ray spectrophotometer on the CORONAS-PHOTON spacecraft measured soft X-ray emission in the 1-15 keV energy range during the deep solar minimum of 2009 with a sensitivity much greater than GOES. Several intervals are identified when the X-ray flux was exceptionally low, and the flux and solar X-ray luminosity are estimated. Spectral fits to the emission at these times give temperatures of 1.7-1.9 MK and emission measures between 4 x 10^47 cm^-3 and 1.1 x 10^48 cm^-3. Comparing Sph...

  19. The Relationship Between Solar Radio and Hard X-Ray Emission

    Science.gov (United States)

    White, S. M.; Benz, A. O.; Christe, S.; Farnik, F.; Kundu, M. R.; Mann, G.; Ning, Z.; Raulin, J.-P.; Silva-Valio, A. V. R.; Saint-Hilaire, P.; hide

    2011-01-01

    This review discusses the complementary relationship between radio and hard Xray observations of the Sun using primarily results from the era of the Reuven Ramaty High Energy Solar Spectroscopic Imager satellite. A primary focus of joint radio and hard X-ray studies of solar flares uses observations of nonthermal gyrosynchrotron emission at radio wavelengths and bremsstrahlung hard X-rays to study the properties of electrons accelerated in the main flare site, since it is well established that these two emissions show very similar temporal behavior. A quantitative prescription is given for comparing the electron energy distributions derived separately from the two wavelength ranges: this is an important application with the potential for measuring the magnetic field strength in the flaring region, and reveals significant differences between the electrons in different energy ranges. Examples of the use of simultaneous data from the two wavelength ranges to derive physical conditions are then discussed, including the case of microflares, and the comparison of images at radio and hard X-ray wavelengths is presented. There have been puzzling results obtained from observations of solar flares at millimeter and submillimeter wavelengths, and the comparison of these results with corresponding hard X-ray data is presented. Finally, the review discusses the association of hard X-ray releases with radio emission at decimeter and meter wavelengths, which is dominated by plasma emission (at lower frequencies) and electron cyclotron maser emission (at higher frequencies), both coherent emission mechanisms that require small numbers of energetic electrons. These comparisons show broad general associations but detailed correspondence remains more elusive.

  20. Tenth International Colloquium on UV and X-Ray Spectroscopy of Astrophysical and Laboratory Plasmas

    Science.gov (United States)

    Silver, Eric H.; Kahn, Steven M.

    UV and X-ray spectroscopy of astrophysical and laboratory plasmas draws interest from many disciplines. Contributions from international specialists are collected together in this book from a timely recent conference. In astrophysics, the Hubble Space Telescope, Astro 1 and ROSAT observatories are now providing UV and X-ray spectra and images of cosmic sources in unprecedented detail, while the Yohkoh mission recently collected superb data on the solar corona. In the laboratory, the development of ion-trap facilities and novel laser experiments are providing vital new data on high temperature plasmas. Recent innovations in the technology of spectroscopic instrumentation are discussed. These papers constitute an excellent up-to-date review of developments in short-wavelength spectroscopy and offer a solid introduction to its theoretical and experimental foundations. These proceedings give an up-to-date review of developments in short-wavelength spectroscopy and offer a solid introduction to its theoretical and experimental foundations. Various speakers presented some of the first results from the high resolution spectrograph on the Hubble Space Telescope, the high sensitivity far ultraviolet and X-ray spectrometers of the ASTRO 1 Observatory, the imaging X-ray spectrometer on the ROSAT Observatory, and the high resolution solar X-ray spectrometer on Yohkoh. The development of ion trap devices had brought about a revolution in laboratory investigations of atomic processes in highly charged atoms. X-ray laser experiments had not only yielded considerable insight into electron ion interactions in hot dense plasmas, but also demonstrated the versatility of laser plasmas as laboratory X-ray sources. Such measurements also motivated and led to refinements in the development of large-scale atomic and molecular codes. On the instrumental side, the design and development of the next series of very powerful short wavelength observatories had generated a large number of

  1. SphinX: The Solar Photometer in X-Rays

    Czech Academy of Sciences Publication Activity Database

    Gburek, S.; Sylwester, J.; Kowalinski, M.; Bakala, J.; Kordylewski, Z.; Podgorski, P.; Plocieniak, S.; Siarkowski, M.; Sylwester, B.; Trzebinski, W.; Kuzin, S.; Pertsov, A.A.; Kotov, Yu. D.; Fárník, František; Reale, F.; Phillips, K. J. H.

    2013-01-01

    Roč. 283, č. 2 (2013), s. 631-649 ISSN 0038-0938 Institutional support: RVO:67985815 Keywords : solar corona * solar instrumentation * X-rays Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 3.805, year: 2013

  2. Microwave and X-Ray emission during a isentropic expansion and its application to solar bursts

    International Nuclear Information System (INIS)

    Piazza, L.R.

    1983-01-01

    The gyro-synchrotron emission in microwaves and the free-free emission in X-rays of a plasma enclosed in a cylinder coincident with a magnetic force tube were calculated for an isentropic self-similar expansion, with plane and cylindrical symmetries. This expansion model was applied to a region of the low solar corona, and the results were compared to the emission observed in some simple solar events of low intensity. The calculations show satisfactory coincidence with the events in X-rays for energies around 10 29 ergs. The solar events analyzed in microwaves, which are not the same that were studied in X-rays, in general do not fit the theoretical results. The origin of the discrepancy is probably the formulation of the processes of emission applied to the expansion. (Author) [pt

  3. The Sun's X-ray Emission During the Recent Solar Minimum

    Science.gov (United States)

    Sylwester, Janusz; Kowalinski, Mirek; Gburek, Szymon; Siarkowski, Marek; Kuzin, Sergey; Farnik, Frantisek; Reale, Fabio; Phillips, Kenneth J. H.

    2010-02-01

    The Sun recently underwent a period of a remarkable lack of major activity such as large flares and sunspots, without equal since the advent of the space age a half century ago. A widely used measure of solar activity is the amount of solar soft X-ray emission, but until recently this has been below the threshold of the X-ray-monitoring Geostationary Operational Environmental Satellites (GOES). There is thus an urgent need for more sensitive instrumentation to record solar X-ray emission in this range. Anticipating this need, a highly sensitive spectrophotometer called Solar Photometer in X-rays (SphinX) was included in the solar telescope/spectrometer TESIS instrument package on the third spacecraft in Russia's Complex Orbital Observations Near-Earth of Activity of the Sun (CORONAS-PHOTON) program, launched 30 January 2009 into a near-polar orbit. SphinX measures X-rays in a band similar to the GOES longer-wavelength channel.

  4. Multi-spacecraft observations of solar hard X-ray bursts

    International Nuclear Information System (INIS)

    Kane, S.R.

    1981-01-01

    The role of multi-spacecraft observations in solar flare research is examined from the point of view of solar hard X-ray bursts and their implications with respect to models of the impulsive phase. Multi-spacecraft measurements provide a stereoscopic view of the flare region, and hence represent the only direct method of measuring directivity of X-rays. In absence of hard X-ray imaging instruments with high spatial and temporal resolution, multi-spacecraft measurements provide the only means of determining the radial (vertical) structure of the hard X-ray source. This potential of the multi-spacecraft observations is illustrated with an analysis of the presently available observations of solar hard X-ray bursts made simultaneously by two or more of the following spacecraft: International Sun Earth Explorer-3 (ISEE-3), Pioneer Venus Orbiter (PVO), Helios-B and High Energy Astrophysical Observatory-A (HEAO-A). In particular, some conclusions have been drawn about the spatial structure and directivity of 50-100 keV X-rays from impulsive flares. Desirable features of future multi-spacecraft missions are briefly discussed followed by a short description of the hard X-ray experiment on the International Solar Polar Mission which has been planned specifically for multi-spacecraft observations of the Sun. (orig.)

  5. Planetary X-ray studies: past, present and future

    Science.gov (United States)

    Branduardi-Raymont, Graziella

    2016-07-01

    Our solar system is a fascinating physics laboratory and X-ray observations are now firmly established as a powerful diagnostic tool of the multiple processes taking place in it. The science that X-rays reveal encompasses solar, space plasma and planetary physics, and the response of bodies in the solar system to the impact of the Sun's activity. This talk will review what we know from past observations and what we expect to learn in the short, medium and long term. Observations with Chandra and XMM-Newton have demonstrated that the origin of Jupiter's bright soft X-ray aurorae lies in the Charge eXchange (CX) process, likely to involve the interaction with atmospheric neutrals of local magnetospheric ions, as well as those carried in the solar wind. At higher energies electron bremsstrahlung is thought to be the X-ray emitting mechanism, while the whole planetary disk acts as a mirror for the solar X-ray flux via Thomson and fluorescent scattering. This 'X-ray mirror' phenomenon is all that is observed from Saturn's disk, which otherwise lacks X-ray auroral features. The Earth's X-ray aurora is bright and variable and mostly due to electron bremsstrahlung and line emission from atmospheric species. Un-magnetised planets, Venus and Mars, do not show X-ray aurorae but display the interesting combination of mirroring the solar X-ray flux and producing X-rays by Solar Wind Charge eXchange (SWCX) in their exospheres. These processes respond to different solar stimulation (photons and solar wind plasma respectively) hence their relative contributions are seen to vary according to the Sun's output. Present and future of planetary X-ray studies are very bright. We are preparing for the arrival of the Juno mission at Jupiter this summer and for coordinated observations with Chandra and XMM-Newton on the approach and later during Juno's orbital phase. These will allow direct correlation of the local plasma conditions with the X-ray emissions and the establishment of the

  6. New Solar Irradiance Measurements from the Miniature X-Ray Solar Spectrometer Cubesat

    Energy Technology Data Exchange (ETDEWEB)

    Woods, Thomas N.; Jones, Andrew; Kohnert, Richard; Mason, James Paul; Moore, Christopher S.; Palo, Scott; Rouleau, Colden [University of Colorado, Boulder, CO (United States); Caspi, Amir [Southwest Research Institute, Boulder, CO (United States); Chamberlin, Phillip C. [NASA Goddard Space Flight Center, Greenbelt, MD (United States); Solomon, Stanley C. [National Center for Atmospheric Research, Boulder, CO (United States); Machol, Janet; Viereck, Rodney [NOAA Space Weather Prediction Center, Boulder, CO (United States)

    2017-02-01

    The goal of the Miniature X-ray Solar Spectrometer ( MinXSS ) CubeSat is to explore the energy distribution of soft X-ray (SXR) emissions from the quiescent Sun, active regions, and during solar flares and to model the impact on Earth's ionosphere and thermosphere. The energy emitted in the SXR range (0.1–10 keV) can vary by more than a factor of 100, yet we have limited spectral measurements in the SXRs to accurately quantify the spectral dependence of this variability. The MinXSS primary science instrument is an Amptek, Inc. X123 X-ray spectrometer that has an energy range of 0.5–30 keV with a nominal 0.15 keV energy resolution. Two flight models have been built. The first, MinXSS -1, has been making science observations since 2016 June 9 and has observed numerous flares, including more than 40 C-class and 7 M-class flares. These SXR spectral measurements have advantages over broadband SXR observations, such as providing the capability to derive multiple-temperature components and elemental abundances of coronal plasma, improved irradiance accuracy, and higher resolution spectral irradiance as input to planetary ionosphere simulations. MinXSS spectra obtained during the M5.0 flare on 2016 July 23 highlight these advantages and indicate how the elemental abundance appears to change from primarily coronal to more photospheric during the flare. MinXSS -1 observations are compared to the Geostationary Operational Environmental Satellite ( GOES ) X-ray Sensor (XRS) measurements of SXR irradiance and estimated corona temperature. Additionally, a suggested improvement to the calibration of the GOES XRS data is presented.

  7. X-ray observations of solar flares with the Einstein Observatory

    International Nuclear Information System (INIS)

    Schmitt, J.H.M.M.; Fink, H.; Harnden, F.R. Jr.; Harvard-Smithsonian Center for Astrophysics, Cambridge, MA)

    1987-01-01

    The first Einstein Observatory Imaging Proportional Counter (IPC) observations of solar flares are presented. These flares were detected in scattered X-ray light when the X-ray telescope was pointed at the sunlit earth. The propagation and scattering of solar X-rays in the earth's atmosphere are discussed in order to be able to deduce the solar X-ray flux incident on top of the atmosphere from scattered X-ray intensity measurements. After this correction, the scattered X-ray data are interpreted as full-disk observations of the sun obtained with the same instrumentation used for observations of flares on other stars. Employing the same data analysis and interpretation techniques, extremely good agreement is found between the physical flare parameters deduced from IPC observations and known properties of compact loop flares. This agreement demonstrates that flare observations with the IPC can reveal physical parameters such as temperature and density quite accurately in the solar case and therefore suggests that the interpretations of stellar X-ray flare observations are on a physically sound basis. 26 references

  8. X-ray line coincidence photopumping in a solar flare

    Science.gov (United States)

    Keenan, F. P.; Poppenhaeger, K.; Mathioudakis, M.; Rose, S. J.; Flowerdew, J.; Hynes, D.; Christian, D. J.; Nilsen, J.; Johnson, W. R.

    2018-03-01

    Line coincidence photopumping is a process where the electrons of an atomic or molecular species are radiatively excited through the absorption of line emission from another species at a coincident wavelength. There are many instances of line coincidence photopumping in astrophysical sources at optical and ultraviolet wavelengths, with the most famous example being Bowen fluorescence (pumping of O III 303.80 Å by He II), but none to our knowledge in X-rays. However, here we report on a scheme where a He-like line of Ne IX at 11.000 Å is photopumped by He-like Na X at 11.003 Å, which predicts significant intensity enhancement in the Ne IX 82.76 Å transition under physical conditions found in solar flare plasmas. A comparison of our theoretical models with published X-ray observations of a solar flare obtained during a rocket flight provides evidence for line enhancement, with the measured degree of enhancement being consistent with that expected from theory, a truly surprising result. Observations of this enhancement during flares on stars other than the Sun would provide a powerful new diagnostic tool for determining the sizes of flare loops in these distant, spatially unresolved, astronomical sources.

  9. SphinX MEASUREMENTS OF THE 2009 SOLAR MINIMUM X-RAY EMISSION

    International Nuclear Information System (INIS)

    Sylwester, J.; Kowalinski, M.; Gburek, S.; Siarkowski, M.; Bakała, J.; Gryciuk, M.; Podgorski, P.; Sylwester, B.; Kuzin, S.; Farnik, F.; Reale, F.; Phillips, K. J. H.

    2012-01-01

    The SphinX X-ray spectrophotometer on the CORONAS-PHOTON spacecraft measured soft X-ray emission in the 1-15 keV energy range during the deep solar minimum of 2009 with a sensitivity much greater than GOES. Several intervals are identified when the X-ray flux was exceptionally low, and the flux and solar X-ray luminosity are estimated. Spectral fits to the emission at these times give temperatures of 1.7-1.9 MK and emission measures between 4 × 10 47 cm –3 and 1.1 × 10 48 cm –3 . Comparing SphinX emission with that from the Hinode X-ray Telescope, we deduce that most of the emission is from general coronal structures rather than confined features like bright points. For one of 27 intervals of exceptionally low activity identified in the SphinX data, the Sun's X-ray luminosity in an energy range roughly extrapolated to that of ROSAT (0.1-2.4 keV) was less than most nearby K and M dwarfs.

  10. SphinX Measurements of the 2009 Solar Minimum X-Ray Emission

    Science.gov (United States)

    Sylwester, J.; Kowalinski, M.; Gburek, S.; Siarkowski, M.; Kuzin, S.; Farnik, F.; Reale, F.; Phillips, K. J. H.; Bakała, J.; Gryciuk, M.; Podgorski, P.; Sylwester, B.

    2012-06-01

    The SphinX X-ray spectrophotometer on the CORONAS-PHOTON spacecraft measured soft X-ray emission in the 1-15 keV energy range during the deep solar minimum of 2009 with a sensitivity much greater than GOES. Several intervals are identified when the X-ray flux was exceptionally low, and the flux and solar X-ray luminosity are estimated. Spectral fits to the emission at these times give temperatures of 1.7-1.9 MK and emission measures between 4 × 1047 cm-3 and 1.1 × 1048 cm-3. Comparing SphinX emission with that from the Hinode X-ray Telescope, we deduce that most of the emission is from general coronal structures rather than confined features like bright points. For one of 27 intervals of exceptionally low activity identified in the SphinX data, the Sun's X-ray luminosity in an energy range roughly extrapolated to that of ROSAT (0.1-2.4 keV) was less than most nearby K and M dwarfs.

  11. SphinX MEASUREMENTS OF THE 2009 SOLAR MINIMUM X-RAY EMISSION

    Energy Technology Data Exchange (ETDEWEB)

    Sylwester, J.; Kowalinski, M.; Gburek, S.; Siarkowski, M.; Bakala, J.; Gryciuk, M.; Podgorski, P.; Sylwester, B. [Space Research Centre, Polish Academy of Sciences, 51-622, Kopernika 11, Wroclaw (Poland); Kuzin, S. [P. N. Lebedev Physical Institute (FIAN), Russian Academy of Sciences, Leninsky Prospect 53, Moscow 119991 (Russian Federation); Farnik, F. [Astronomical Institute, Ondrejov Observatory (Czech Republic); Reale, F. [Dipartimento di Fisica, Universita di Palermo, Palermo, Italy, and INAF, Osservatorio Astronomico di Palermo, Palermo (Italy); Phillips, K. J. H., E-mail: js@cbk.pan.wroc.pl [Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey RH5 6NT (United Kingdom)

    2012-06-01

    The SphinX X-ray spectrophotometer on the CORONAS-PHOTON spacecraft measured soft X-ray emission in the 1-15 keV energy range during the deep solar minimum of 2009 with a sensitivity much greater than GOES. Several intervals are identified when the X-ray flux was exceptionally low, and the flux and solar X-ray luminosity are estimated. Spectral fits to the emission at these times give temperatures of 1.7-1.9 MK and emission measures between 4 Multiplication-Sign 10{sup 47} cm{sup -3} and 1.1 Multiplication-Sign 10{sup 48} cm{sup -3}. Comparing SphinX emission with that from the Hinode X-ray Telescope, we deduce that most of the emission is from general coronal structures rather than confined features like bright points. For one of 27 intervals of exceptionally low activity identified in the SphinX data, the Sun's X-ray luminosity in an energy range roughly extrapolated to that of ROSAT (0.1-2.4 keV) was less than most nearby K and M dwarfs.

  12. Soft X-Ray amplification in laser plasmas

    International Nuclear Information System (INIS)

    Louis-Jacquet, M.

    1988-01-01

    The principles, experiments and theoretical models of soft x-ray, amplification, produced in laser plasmas, are studied. In the discussion of the principles, the laser plasma medium, the definition of the gain, the population inversions, saturation and superradiance are described. The results concerning recombination and collisional excitation experiments, as well as experimental devices are shown. A complete physical simulation to design and interpret x-ray laser experiments is given. Applications of x-ray lasers in grating production techniques, in contact microscopy and holography are considered

  13. Stellar and solar X-ray polarimetry

    Energy Technology Data Exchange (ETDEWEB)

    Novick, R [Columbia Univ., New York (USA)

    1975-12-01

    The scientific motivation for X-ray polarimetry is discussed with particular emphasis on the information that might be obtained on the binary X-ray pulsars in addition to a number of other classes of objects including solar flares. Detailed discussions are given for Thomson-scattering and Bragg-crystal polarimeters with numerical estimates for the sensitivity of various existing and proposed instruments.

  14. Laser plasma X-ray for non-destructive inspection

    International Nuclear Information System (INIS)

    Yagi, T.; Kusama, H.

    1995-01-01

    External electric field is applied to the laser produced plasma, and its found that plasma shape in soft X-ray region is changed due to the penetrating electric field. The plasma emits strong hard X-ray, which can be used as a compact light source for non-destructive inspection. (author)

  15. Soft x-ray spectrographs for solar observations

    International Nuclear Information System (INIS)

    Bruner, M.E.

    1988-01-01

    This paper surveys some of the recent advances in the state of the art of soft X-ray spectrometers, particularly as they might be applied to Solar Observations. The discussions center on the windowless region from roughly 1 to 100 A, and covers both grating and crystal instruments. The author begins with a short discussion of the solar soft X-ray spectrum and its interpretation, followed by a few general comments on problems peculiar to soft X-ray instruments. The paper reviews of recent developments in spectrometer optical design, which has been a lively field during the last dozen years. This is particularly true in the case of grating spectrometers. The paper concludes with a short section on telescope considerations, and some remarks on future flight opportunities

  16. The Instruments and Capabilities of the Miniature X-Ray Solar Spectrometer (MinXSS) CubeSats

    Science.gov (United States)

    Moore, Christopher S.; Caspi, Amir; Woods, Thomas N.; Chamberlin, Phillip C.; Dennis, Brian R.; Jones, Andrew R.; Mason, James P.; Schwartz, Richard A.; Tolbert, Anne K.

    2018-02-01

    The Miniature X-ray Solar Spectrometer (MinXSS) CubeSat is the first solar science oriented CubeSat mission flown for the NASA Science Mission Directorate, with the main objective of measuring the solar soft X-ray (SXR) flux and a science goal of determining its influence on Earth's ionosphere and thermosphere. These observations can also be used to investigate solar quiescent, active region, and flare properties. The MinXSS X-ray instruments consist of a spectrometer, called X123, with a nominal 0.15 keV full-width at half-maximum (FWHM) resolution at 5.9 keV and a broadband X-ray photometer, called XP. Both instruments are designed to obtain measurements from 0.5 - 30 keV at a nominal time cadence of 10 s. A description of the MinXSS instruments, performance capabilities, and relation to the Geostationary Operational Environmental Satellite (GOES) 0.1 - 0.8 nm flux is given in this article. Early MinXSS results demonstrate the capability of measuring variations of the solar spectral soft X-ray (SXR) flux between 0.8 - 12 keV from at least GOES A5-M5 (5 × 10^{-8} - 5 ×10^{-5} W m^{-2}) levels and of inferring physical properties (temperature and emission measure) from the MinXSS data alone. Moreover, coronal elemental abundances can be inferred, specifically for Fe, Ca, Si, Mg, S, Ar, and Ni, when the count rate is sufficiently high at each elemental spectral feature. Additionally, temperature response curves and emission measure loci demonstrate the MinXSS sensitivity to plasma emission at different temperatures. MinXSS observations coupled with those from other solar observatories can help address some of the most compelling questions in solar coronal physics. Finally, simultaneous observations by MinXSS and the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) can provide the most spectrally complete soft X-ray solar flare photon flux measurements to date.

  17. Electron cyclotron resonance ion source plasma characterization by X-ray spectroscopy and X-ray imaging

    Energy Technology Data Exchange (ETDEWEB)

    Mascali, David, E-mail: davidmascali@lns.infn.it; Castro, Giuseppe; Celona, Luigi; Neri, Lorenzo; Gammino, Santo [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Biri, Sándor; Rácz, Richárd; Pálinkás, József [Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/c, H-4026 Debrecen (Hungary); Caliri, Claudia [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Università degli Studi di Catania, Dip.to di Fisica e Astronomia, via Santa Sofia 64, 95123 Catania (Italy); Romano, Francesco Paolo [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); CNR, Istituto per i Beni Archeologici e Monumentali, Via Biblioteca 4, 95124 Catania (Italy); Torrisi, Giuseppe [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Università Mediterranea di Reggio Calabria, DIIES, Via Graziella, I-89100 Reggio Calabria (Italy)

    2016-02-15

    An experimental campaign aiming to investigate electron cyclotron resonance (ECR) plasma X-ray emission has been recently carried out at the ECRISs—Electron Cyclotron Resonance Ion Sources laboratory of Atomki based on a collaboration between the Debrecen and Catania ECR teams. In a first series, the X-ray spectroscopy was performed through silicon drift detectors and high purity germanium detectors, characterizing the volumetric plasma emission. The on-purpose developed collimation system was suitable for direct plasma density evaluation, performed “on-line” during beam extraction and charge state distribution characterization. A campaign for correlating the plasma density and temperature with the output charge states and the beam intensity for different pumping wave frequencies, different magnetic field profiles, and single-gas/gas-mixing configurations was carried out. The results reveal a surprisingly very good agreement between warm-electron density fluctuations, output beam currents, and the calculated electromagnetic modal density of the plasma chamber. A charge-coupled device camera coupled to a small pin-hole allowing X-ray imaging was installed and numerous X-ray photos were taken in order to study the peculiarities of the ECRIS plasma structure.

  18. Millimeter and X-Ray Emission from the 5 July 2012 Solar Flare

    Science.gov (United States)

    Tsap, Y. T.; Smirnova, V. V.; Motorina, G. G.; Morgachev, A. S.; Kuznetsov, S. A.; Nagnibeda, V. G.; Ryzhov, V. S.

    2018-03-01

    The 5 July 2012 solar flare SOL2012-07-05T11:44 (11:39 - 11:49 UT) with an increasing millimeter spectrum between 93 and 140 GHz is considered. We use space and ground-based observations in X-ray, extreme ultraviolet, microwave, and millimeter wave ranges obtained with the Reuven Ramaty High-Energy Solar Spectroscopic Imager, Solar Dynamics Observatory (SDO), Geostationary Operational Environmental Satellite, Radio Solar Telescope Network, and Bauman Moscow State Technical University millimeter radio telescope RT-7.5. The main parameters of thermal and accelerated electrons were determined through X-ray spectral fitting assuming the homogeneous thermal source and thick-target model. From the data of the Atmospheric Imaging Assembly/SDO and differential-emission-measure calculations it is shown that the thermal coronal plasma gives a negligible contribution to the millimeter flare emission. Model calculations suggest that the observed increase of millimeter spectral flux with frequency is determined by gyrosynchrotron emission of high-energy (≳ 300 keV) electrons in the chromosphere. The consequences of the results are discussed in the light of the flare-energy-release mechanisms.

  19. Nondispersive x-ray diagnostics of short lived plasmas

    International Nuclear Information System (INIS)

    Day, R.H.

    1983-01-01

    In this NATO Advanced Study Institute, we have discussed in detail the diagnosis of many pulse power machine properties, including their electrical behavior, grounding and shielding, and related data acquisition techniques. The purpose for many of these machines is to create high temperature/high density plasmas and, therefore, the subsequent behavior of these plasmas is of critical concern. The energy density of these plasmas is such that they will naturally radiate in the x-ray regime and thus the diagnosis of their x-ray emission is a crucial measurement of the entire system performance. In this lecture, I describe the general techniques used to perform nondispersive x-ray diagnostics of these short lived plasmas

  20. Characterization of X-ray emission from laser generated plasma

    Science.gov (United States)

    Cannavò, Antonino; Torrisi, Lorenzo; Ceccio, Giovanni; Cutroneo, Mariapompea; Calcagno, Lucia; Sciuto, Antonella; Mazzillo, Massimo

    2018-01-01

    X-ray emission from laser generated plasma was studied at low (1010 W/cm2) and high (1018 W/cm2) intensity using ns and fs laser, respectively. Plasma characteristics were controlled trough the laser parameters, the irradiation conditions and the target properties. The X-ray spectra were acquired using fast detection technique based on SiC diodes with different active regions. The X-ray yield increases with the atomic number of the target, both at low and high intensity, and a similar empirical law has been obtained. The X-ray emission mechanisms from plasma are correlated to the plasma temperature and density and to the Coulomb charge particle acceleration, due to the charge separation effects produced in the non-equilibrium plasma. Functional dependences, theoretical approaches and interpretation of possible mechanism will be presented and discussed.

  1. Characterization of X-ray emission from laser generated plasma

    Directory of Open Access Journals (Sweden)

    Cannavò Antonino

    2018-01-01

    Full Text Available X-ray emission from laser generated plasma was studied at low (1010 W/cm2 and high (1018 W/cm2 intensity using ns and fs laser, respectively. Plasma characteristics were controlled trough the laser parameters, the irradiation conditions and the target properties. The X-ray spectra were acquired using fast detection technique based on SiC diodes with different active regions. The X-ray yield increases with the atomic number of the target, both at low and high intensity, and a similar empirical law has been obtained. The X-ray emission mechanisms from plasma are correlated to the plasma temperature and density and to the Coulomb charge particle acceleration, due to the charge separation effects produced in the non-equilibrium plasma. Functional dependences, theoretical approaches and interpretation of possible mechanism will be presented and discussed.

  2. THE THERMAL PROPERTIES OF SOLAR FLARES OVER THREE SOLAR CYCLES USING GOES X-RAY OBSERVATIONS

    International Nuclear Information System (INIS)

    Ryan, Daniel F.; Gallagher, Peter T.; Milligan, Ryan O.; Dennis, Brian R.; Kim Tolbert, A.; Schwartz, Richard A.; Alex Young, C.

    2012-01-01

    Solar flare X-ray emission results from rapidly increasing temperatures and emission measures in flaring active region loops. To date, observations from the X-Ray Sensor (XRS) on board the Geostationary Operational Environmental Satellite (GOES) have been used to derive these properties, but have been limited by a number of factors, including the lack of a consistent background subtraction method capable of being automatically applied to large numbers of flares. In this paper, we describe an automated Temperature and Emission measure-Based Background Subtraction method (TEBBS), that builds on the methods of Bornmann. Our algorithm ensures that the derived temperature is always greater than the instrumental limit and the pre-flare background temperature, and that the temperature and emission measure are increasing during the flare rise phase. Additionally, TEBBS utilizes the improved estimates of GOES temperatures and emission measures from White et al. TEBBS was successfully applied to over 50,000 solar flares occurring over nearly three solar cycles (1980-2007), and used to create an extensive catalog of the solar flare thermal properties. We confirm that the peak emission measure and total radiative losses scale with background subtracted GOES X-ray flux as power laws, while the peak temperature scales logarithmically. As expected, the peak emission measure shows an increasing trend with peak temperature, although the total radiative losses do not. While these results are comparable to previous studies, we find that flares of a given GOES class have lower peak temperatures and higher peak emission measures than previously reported. The TEBBS database of flare thermal plasma properties is publicly available at http://www.SolarMonitor.org/TEBBS/.

  3. Characteristics of X-ray photons in tilted incident laser-produced plasma

    International Nuclear Information System (INIS)

    Wang Ruirong; Chen Weimin; Xie Dongzhu

    2008-01-01

    Characteristics of X-ray and spout direction of heat plasma flow were studied on Shenguang-II laser facility. Using of pinhole X-ray camera, X-ray photons from the plasma of aluminum (Al) irradiated by 1.053 μm laser, was measured and analysed. It is observed that the spatial distribution of X-ray photons in Al plasma for tilted irradiation is symmetic at the center of the target. The spout direction of heat plasma flow is inferred by the distribution contour of X-ray photons. the experimental results show that the spout direction of heat plasma flow is normal to target plane and the output intensity of X-ray photons does not increase significantly for tilted laser incidence. Uniformity of laser energy deposition is improved by superposing tilted incident and laser perpendicularly incident laser. At the same time, it is found that the conversion efficiency from the tilted incident laser energy to X-ray photons of laser-produced plasma is decreased. (authors)

  4. Revising the Local Bubble Model due to Solar Wind Charge Exchange X-ray Emission

    Science.gov (United States)

    Shelton, Robin L.

    2009-03-01

    The hot Local Bubble surrounding the solar neighborhood has been primarily studied through observations of its soft X-ray emission. The measurements were obtained by attributing all of the observed local soft X-rays to the bubble. However, mounting evidence shows that the heliosphere also produces diffuse X-rays. The source is solar wind ions that have received an electron from another atom. The presence of this alternate explanation for locally produced diffuse X-rays calls into question the existence and character of the Local Bubble. This article addresses these questions. It reviews the literature on solar wind charge exchange (SWCX) X-ray production, finding that SWCX accounts for roughly half of the observed local 1/4 keV X-rays found at low latitudes. This article also makes predictions for the heliospheric O VI column density and intensity, finding them to be smaller than the observational error bars. Evidence for the continued belief that the Local Bubble contains hot gas includes the remaining local 1/4 keV intensity, the observed local O VI column density, and the need to fill the local region with some sort of plasma. If the true Local Bubble is half as bright as previously thought, then its electron density and thermal pressure are 1/sqrt{2} as great as previously thought, and its energy requirements and emission measure are 1/2 as great as previously thought. These adjustments can be accommodated easily, and, in fact, bring the Local Bubble’s pressure more in line with that of the adjacent material. Suggestions for future work are made.

  5. Time resolved x-ray photography of a dense plasma focus

    International Nuclear Information System (INIS)

    Burnett, J.C.; Meyer, J.; Rankin, G.

    1977-01-01

    The temporal development of the hot plasma in a dense plasma focus is studied by x-ray streak photography of approximately 2 ns resolution time. It is shown that initially a uniform x-ray emitting pinch plasma is formed which subsequently cools down until x-ray emission stops after approximately 50 ns. At a time of around 100 ns after initial x-ray emission coinciding with the break-up time of the pinch a second burst of x-rays is observed coming from small localized regions. The observations are compared with results obtained from time-resolved shadow and schlieren photography of a similar dense focus discharge. (author)

  6. X-ray emission lines from photoionized plasmas

    International Nuclear Information System (INIS)

    Liedahl, D.A.

    1992-11-01

    Plasma emission codes have become a standard tool for the analysis of spectroscopic data from cosmic X-ray sources. However, the assumption of collisional equilibrium, typically invoked in these codes, renders them inapplicable to many important astrophysical situations, particularly those involving X-ray photoionized nebulae, which are likely to exist in the circumsource environments of compact X-ray sources. X-ray line production in a photoionized plasma is primarily the result of radiative cascades following recombination. Through the development of atomic models of several highly-charged ions, this work extends the range of applicability of discrete spectral models to plasmas dominated by recombination. Assuming that ambient plasma conditions lie in the temperature range 10 5 --10 6 K and the density range 10 11 --10 16 cm -3 , X-ray line spectra are calculated over the wavelength range 5--45 angstrom using the HULLAC atomic physics package. Most of the work focuses on the Fe L-shell ions. Line ratios of the form (3s-2p)/(3d-2p) are shown to characterize the principal mode of line excitation, thereby providing a simple signature of photoionization. At electron densities exceeding 10 12 cm -3 , metastable state populations in the ground configurations approach their LTE value, resulting in the enrichment of the Fe L-shell recombination spectrum and a set of density-sensitive X-ray line ratios. Radiative recombination continua and emission lines produced selectively by Δn = 0 dielectronic recombination are shown to provide two classes of temperature diagnostics. Because of the extreme overionization, the recombination continua are expected to be narrow (ΔE/E much-lt 1), with ΔE = kT. Dielectronic recombination selectively drives radiative transitions that originate on states with vacancies in the 2s subshell, states that are inaccessible under pure RR population kinetics

  7. Modeling X-ray Spectra of Astrophysical Plasmas: Current Status and Future Needs

    Science.gov (United States)

    Smith, Randall

    Existing high-resolution astrophysical X-ray spectra has exposed the need for high-quality atomic data of all stripes: wavelengths, collisional and absorption cross sections, and radiative rates. The Astro-H soft X-ray spectrometer (2015 launch) will vastly increase the number and type of high-resolution X-ray spectra available and likely expose a number of shortcomings in our models. I will describe recent advances in theoretical calculations and laboratory measurements, as well as a number of existing needs in the field. These include accurate soft X-ray wavelengths for L-shell ions, diagnostic emission line ratios with estimated error bars, and high-resolution absorption cross sections for abundant ions and molecules. Finally, new models of emission from non-equilibrium ionization plasmas and astrophysical charge exchange will be discussed. This latter emission arises due to the interaction of highly charged ions with neutral atoms, forming a diffuse background in the case of solar wind ions and possibly also arising in more distant environments.

  8. The Solar-A soft X-ray telescope experiment

    Science.gov (United States)

    Acton, L.; Bruner, M.; Brown, W.; Lemen, J.; Hirayama, T.

    1988-01-01

    The Japanese Solar-A mission for the study of high energy solar physics is timed to observe the sun during the next activity maximum. This small spacecraft includes a carefully coordinated complement of instruments for flare studies. In particular, the soft X-ray telescope (SXT) will provide X-ray images of flares with higher sensitivity and time resolution than have been available before. This paper describes the scientific capabilities of the SXT and illustrates its application to the study of an impulsive compact flare.

  9. Spectroscopy of X-ray Photoionized Plasmas in the Laboratory

    Science.gov (United States)

    Liedahl, Duane A.; Loisel, Guillaume; Bailey, James E.; Nagayama, Taisuke; Hansen, Stephanie B.; Rochau, Gregory; Fontes, Christopher J.; Mancini, Roberto; Kallman, Timothy R.

    2018-06-01

    The physical processes operating in astrophysical plasmas --- heating, cooling, ionization, recombination, level population kinetics, and radiation transport --- are all accessible to observation in the laboratory. What distinguishes X-ray photoionized plasmas from the more common case of high-temperature collisionally-ionized plasmas is the elevated level of importance of the radiation/matter interaction. The advent of laboratory facilities with the capability to generate high-powered X-ray sources has provided the means by which to study this interaction, which is also fundamental to active galactic nuclei and other accretion-powered objects. We discuss recent and ongoing experiments, with an emphasis on X-ray spectroscopic measurements of silicon plasmas obtained at the Sandia Z Pulsed Power Facility.

  10. Soft X-ray variability over the present minimum of solar activity as observed by SphinX

    Science.gov (United States)

    Gburek, S.; Siarkowski, M.; Kepa, A.; Sylwester, J.; Kowalinski, M.; Bakala, J.; Podgorski, P.; Kordylewski, Z.; Plocieniak, S.; Sylwester, B.; Trzebinski, W.; Kuzin, S.

    2011-04-01

    Solar Photometer in X-rays (SphinX) is an instrument designed to observe the Sun in X-rays in the energy range 0.85-15.00 keV. SphinX is incorporated within the Russian TESIS X and EUV telescope complex aboard the CORONAS-Photon satellite which was launched on January 30, 2009 at 13:30 UT from the Plesetsk Cosmodrome, northern Russia. Since February, 2009 SphinX has been measuring solar X-ray radiation nearly continuously. The principle of SphinX operation and the content of the instrument data archives is studied. Issues related to dissemination of SphinX calibration, data, repository mirrors locations, types of data and metadata are discussed. Variability of soft X-ray solar flux is studied using data collected by SphinX over entire mission duration.

  11. Characteristic studies on solar x-ray flares and solar radio bursts during descending phases of solar cycles 22 and 23

    International Nuclear Information System (INIS)

    Bhattacharya, J.; De, B.K.; Guha, A.

    2014-01-01

    In this paper, a comparative study between the solar X-ray flares and solar radio bursts in terms of their duration and energy has been done. This has been done by analyzing the data in a statistical way covering the descending phase of the 22nd and 23rd solar cycles. It has been observed that the most probable value of duration of both solar X-ray flares and solar radio bursts remain same for a particular cycle. There is a slight variation in the most probable value of duration in going from 22nd cycle to 23rd cycle in the case of both kinds of events. This small variation may be due to the variation of polar field. A low correlation has been observed between energy fluxes in solar X-ray flares and in solar radio bursts. This has been attributed to the non symmetric contribution of energy to the solar radio and X-ray band controlled by solar magnetic field

  12. Studies of solar flares: Homology and X-ray line broadening

    Science.gov (United States)

    Ranns, Neale David Raymond

    This thesis starts with an introduction to the solar atmosphere and the physics that governs its behaviour. The formation processes of spectral lines are presented followed by an explanation of employed plasma diagnostic techniques and line broadening mechanisms. The current understanding on some principle concepts of flare physics are reviewed and the topics of flare homology and non-thermal line broadening are introduced. The many solar satellites and instrumentation that were utilised during this thesis are described. Analysis techniques for some instruments are also presented. A series of solar flares that conform to the literature definition for homologous flares are examined. The apparent homology is shown to be caused by emerging flux rather than continual stressing of a single, or group of, magnetic structure's. The implications for flare homology are discussed. The analysis of a solar flare with a rise and peak in the observed non-thermal X-ray line broadening (Vnt) is then performed. The location of the hot plasma within the flare area is determined and consequently the source of Vnt is located to be within and above the flare loops. The flare footpoints are therefore discarded as a possible source location. Viable source locations are discussed with a view to determining the dominant mechanism for the generation of line broadening. The timing relationships between the hard X-ray (HXR) flux and Vnt in many solar flares are then examined. I show that there is a causal relationship between these two parameters and that the HXR rise time is related to the time delay between the maxima of HXR flux and Vnt. The temporal evolution of Vnt is shown to be dependent upon the shape of the HXR burst. The implications of these results are discussed in terms of determining the line broadening mechanism and the limitations of the data. A summary of the results in this thesis is then presented together with suggestions for future research.

  13. Dynamics of a multiple-pulse-driven x-ray laser plasma

    International Nuclear Information System (INIS)

    Wan, A.S.; Da Silva, L.B.; Moreno, J.C.; Cauble, R.; Celliers, P.; Dalhed, H.E. Jr.; Koch, J.A.; Nilsen, J.

    1996-01-01

    In this paper we describe experimental and computational studies of multiple-pulse-driven laser plasma, which is the gain medium for a neon-like yttrium x-ray laser. Near-field emission profiles have been measured both with and without reinjection of the x-ray laser photons to couple with the amplifying medium created by later pulses using an external multilayer mirror. From the temporal and spatial evolution of the near-field emission profiles we can examine the pulse-to-pulse variation of the x-ray laser plasma due to changes in the hydrodynamics, laser deposition, and the injecting of x-ray laser photons back into an amplifying x-ray laser plasma. Using a combination of radiation hydrodynamics, atomic kinetics, and ray propagation codes, reasonable agreement has been obtained between simulations and the experimental results. copyright 1996 American Institute of Physics

  14. X-ray emission characteristics of foam target plasmas

    International Nuclear Information System (INIS)

    Fronya, A.A.; Borisenko, N.G.; Chernodub, M.L.; Merkuliev, Yu.A.; Osipov, M.V.; Puzyrev, V.N.; Sahakyan, A.T.; Starodub, A.N.; Vasin, B.L.; Yakushev, O.F.

    2010-01-01

    Complete text of publication follows. Experimental results of laser radiation interaction with a foam targets are presented. The spatial, temporal and energy characteristics of x-ray plasma radiation have been investigated. The pinhole-camera and Schwarzschild objective have been used for the plasma image formation in different spectral ranges. The plasma image is registered by the Schwarzschild objective in a narrow spectral range 180 - 200 A. Spectral characteristics of x-ray radiation registered by pinhole-camera have been defined by means outer filters. The use of the filters with different transmission curves allowed one the determine the localization of x-ray radiation with fixed wavelength. Spatial resolution accounts 16 μm in the pinhole-camera diagnostic channel and 2.5 μm in the Schwarzschild objective diagnostic channel. The plasma images in the intrinsic x-ray radiation show that the emission area in the transverse direction with respect to the direction of the propagating heating radiation exceeds the focal spot size. This fact indicates that the target heating in the transverse direction is due to internal energy of the created plasma. The average value of plasma electron temperature is ∼ 0.4 - 1.4 keV. Acknowledgements. The work is partly supported by the Russian Foundation for Basic Researches, grant no. 10-02-00113 and by Federal Target Program 'Research and scientific-pedagogical cadres of Innovative Russia' (grant 2009-1.1-122-052-025).

  15. HOT PLASMA FROM SOLAR ACTIVE-REGION CORES: CONSTRAINTS FROM THE HINODE X-RAY TELESCOPE

    Energy Technology Data Exchange (ETDEWEB)

    Schmelz, J. T. [USRA, 7178 Columbia Gateway Drive, Columbia, MD 21046 (United States); Christian, G. M.; Matheny, P. O., E-mail: jschmelz@usra.edu [Physics Department, University of Memphis, Memphis, TN 38152 (United States)

    2016-12-20

    Mechanisms invoked to heat the solar corona to millions of degrees kelvin involve either magnetic waves or magnetic reconnections. Turbulence in the convection zone produces MHD waves, which travel upward and dissipate. Photospheric motions continuously build up magnetic energy, which is released through magnetic reconnection. In this paper, we concentrate on hot non-flaring plasma with temperatures of 5 MK <  T  < 10 MK because it is one of the few observables for which wave and reconnection models make different predictions. Wave models predict no (or little) hot plasma, whereas reconnection models predict it, although in amounts that are challenging to detect with current instrumentation. We used data from the X-ray Telescope (XRT) and the Atmospheric Imaging Assembly (AIA). We requested a special XRT observing sequence, which cycled through the thickest XRT filter several times per hour so we could average these images and improve the signal-to-noise. We did differential emission measure (DEM) analysis using the time-averaged thick-filter data as well as all available channels from both the XRT and AIA for regions observed on 2014 December 11. Whereas our earlier work was only able to determine that plasma with a temperature greater than 5 MK was present , we are now able to find a well-constrained DEM distribution. We have therefore added a strong observational constraint that must be explained by any viable coronal heating model. Comparing state-of-the-art wave and reconnection model predictions, we can conclude that reconnection is heating the hot plasma in these active regions.

  16. Resolving the Origin of the Diffuse Soft X-ray Background

    Science.gov (United States)

    Smith, Randall K.; Foster, Adam R.; Edgar, Ricard J.; Brickhouse, Nancy S.; Sanders, Wilton T.

    2012-01-01

    In January 1993, the Diffuse X-ray Spectrometer (DXS) measured the first high-resolution spectrum of the diffuse soft X-ray background between 44-80A. A line-dominated spectrum characteristic of a 10(exp 6)K collisionally ionized plasma' was expected but while the observed spectrum was clearly line-dominated, no model would fit. Then in 2003 the Cosmic Hot Interstellar Plasma Spectrometer (CHIPS) launched and observed the diffuse extreme-ultraviolet (EUV) spectrum between 90- 265A. Although many emission lines were again expected; only Fe IX at 171.1A was detected. The discovery of X-rays from comets led to the realization that heavy ions (Z=6-28) in the solar wind will emit soft X-rays as the ions interact via charge exchange with neutral atoms in the heliosphere and geocorona. Using a new model for solar wind charge exchange (SWCX) emission, we show that the diffuse soft X-ray background can be understood as a combination of emission from charge exchange onto the slow and fast solar wind together with a more distant and diffuse hot (10(exp 6)K) plasma.

  17. Time correlation between plasma behaviour and soft x-ray emission in a plasma focus

    International Nuclear Information System (INIS)

    Hirano, Katsumi; Tagaya, Yutaka; Shimoda, Katsuji; Okabe, Yushiro; Yamamoto, Toshikazu

    1986-01-01

    Soft X-rays emitted from a plasma focus are investigated experimentally. In contrast to single-pulsive burst of neutron, hard X-rays, ion- and electron beams, the soft X-rays are observed from the collapse phase to the decay phase of the plasma column, and have typically three successive peaks in its signal. Each peak corresponds to the maximum compression, the disruption and the decay phase of plasma column. It is revealed that the first and the second peaks are radiated by plasma itself, whereas the third peak is caused by emission from the inner electrode face. (author)

  18. SMM x ray polychromator

    Science.gov (United States)

    Saba, J. L. R.

    1993-01-01

    The objective of the X-ray Polychromator (XRP) experiment was to study the physical properties of solar flare plasma and its relation to the parent active region to understand better the flare mechanism and related solar activity. Observations were made to determine the temperature, density, and dynamic structure of the pre-flare and flare plasma as a function of wavelength, space and time, the extent to which the flare plasma departs from thermal equilibrium, and the variation of this departure with time. The experiment also determines the temperature and density structure of active regions and flare-induced changes in the regions.

  19. Common observations of solar X-rays from SPHINX/CORONAS-PHOTON and XRS/MESSENGER

    Science.gov (United States)

    Kepa, Anna; Sylwester, Janusz; Sylwester, Barbara; Siarkowski, Marek; Mrozek, Tomasz; Gryciuk, Magdalena; Phillips, Kenneth

    SphinX was a soft X-ray spectrophotometer constructed in the Space Research Centre of Polish Academy of Sciences. The instrument was launched on 30 January 2009 aboard CORONAS-PHOTON satellite as a part of TESIS instrument package. SphinX measured total solar X-ray flux in the energy range from 1 to 15 keV during the period of very low solar activity from 20 February to 29 November 2009. For these times the solar detector (X-ray Spectrometer - XRS) onboard MESSENGER also observed the solar X-rays from a different vantage point. XRS measured the radiation in similar energy range. We present results of the comparison of observations from both instruments and show the preliminary results of physical analysis of spectra for selected flares.

  20. SphinX: A Fast Solar Photometer in X-rays J. Sylwester , S. Kuzin ...

    Indian Academy of Sciences (India)

    NAS solar mission. SphinX (Solar Photometer in X-rays) will use PIN silicon detectors for high time resolution (0.01 s) measurements of the solar spectra of .... right panel of Fig. 2. In this NBF concept, three fluorescing targets illuminate a single. PIN detector. The fluorescence radiation is coming from three different pure ...

  1. X-ray heating of laboratory photoionized plasmas at Z

    Science.gov (United States)

    Mancini, R.; Lockard, T.; Mayes, D.; Loisel, G.; Bailey, J.; Rochau, G.; Abdallah, J.; Fontes, C.; Liedahl, D.; Golovkin, I.

    2017-10-01

    In separate experiments performed at the Z facility of Sandia National Laboratories two different samples were employed to produce and characterize photoionized plasmas. One was a gas cell filled with neon, and the other was a thin silicon layer coated with plastic. Both samples were driven by the broadband x-ray flux produced at the collapse of a wire array z-pinch implosion. Transmission spectroscopy of a narrowband portion of the x-ray flux was used to diagnose the charge state distribution, and the electron temperature was extracted from a Li-like ion level population ratio. To interpret the temperature measurement, we performed Boltzmann kinetics and radiation-hydrodynamic simulations. We found that non-equilibrium atomic physics and the coupling of the radiation flux to the level population kinetics play a critical role in modeling the x-ray heating of photoionized plasmas. In spite of being driven by similar x-ray drives, differences of ionization and charged state distributions in the neon and silicon plasmas are reflected in the plasma heating and observed temperatures. DOE OFES Grant DE-SC0014451 and ZFSP.

  2. Development of laser plasma x-ray microscope for living hydrated biological specimens

    International Nuclear Information System (INIS)

    Kado, Masataka; Daido, Hiroyuki

    2005-01-01

    Investigating the structure and the function of life object performing advanced life activity becomes important. In order to investigate the life object, it is necessary to observe living specimens with high spatial resolution and high temporal resolution. Since laser plasma x-ray source has high brightness and short pulse duration, x-ray microscope with the laser plasma x-ray source makes possible to observe living specimens. Such as chromosomes, macrophages, bacterium, and so on have been observed by contact x-ray microscopy. The x-ray images obtained by indirect measurements such as the contact x-ray microscopy have difficulty to avoid artificial effect such as irregular due to developing process. Development of an x-ray microscope with laser plasma x-ray source is necessary to avoid such defects. (author)

  3. The soft X-ray telescope for the SOLAR-A mission

    Science.gov (United States)

    Tsuneta, S.; Acton, L.; Bruner, M.; Lemen, J.; Brown, W.; Caravalho, R.; Catura, R.; Freeland, S.; Jurcevich, B.; Owens, J.

    1991-01-01

    The Soft X-ray Telescope (SXT) of the SOLAR-A mission is designed to produce X-ray movies of flares with excellent angular and time resolution as well as full-disk X-ray images for general studies. A selection of thin metal filters provide a measure of temperature discrimination and aid in obtaining the wide dynamic range required for solar observing. The co-aligned SXT aspect telescope will yield optical images for aspect reference, white-light flare and sunspot studies, and, possibly, helioseismology. This paper describes the capabilities and characteristics of the SXT for scientific observing.

  4. X-ray diodes for laser fusion plasma diagnostics

    International Nuclear Information System (INIS)

    Day, R.H.; Lee, P.; Saloman, E.B.; Nagel, D.J.

    1981-02-01

    Photodiodes with x-ray sensitive photocathodes are commonly used as broadband x-ray detectors in fusion plasma diagnostics. We have measured the risetime of the detector system and have measured the quantum efficiency between 1 to 500 A of numerous photocathode materials of practical interest. The materials studied include aluminum, copper, nickel, gold, three forms of carbon, chromium, and cesium iodide. The results of the measurements are compared with Henke's semiempirical model of photoyield. We have studied the effects of long-term cathode aging and use as a plasma diagnostic on cathode quantum efficiency. In addition, we have measured the x-ray mass-absorption coefficient of several ultrasoft x-ray windows in energy regions where data were unavailable. Windows studied were made of aluminum, Formvar, polypropylene, and Kimfoil. Measurements between 1 to 50 A were performed with the Los Alamos Scientific Laboratory's low-energy x-ray calibration facility, and the measurements between 50 to 550 A were performed at the National Bureau of Standard's synchrotron ultraviolet radiation facility

  5. Soft x-ray source by laser produced Xe plasma

    International Nuclear Information System (INIS)

    Amano, Sho; Masuda, Kazuya; Miyamoto, Shuji; Mochizuki, Takayasu

    2010-01-01

    The laser plasma soft X-ray source in the wavelength rage of 5-17 nm was developed, which consisted of the rotating drum system supplying cryogenic Xe target and the high repetition rate pulse Nd:YAG slab laser. We found the maximum conversion efficiency of 30% and it demonstrated the soft X-ray generation with the high repetition rate pulse of 320 pps and the high average power of 20 W. The soft X-ray cylindrical mirror was developed and successfully focused the soft X-ray with an energy intensity of 1.3 mJ/cm 2 . We also succeeded in the plasma debris mitigation with Ar gas. This will allow a long lifetime of the mirror and a focusing power intensity of 400 mW/cm 2 with 320 pps. The high power soft X-ray is useful for various applications. (author)

  6. Multi-wavelength imaging of solar plasma. High-beta disruption model of solar flares

    International Nuclear Information System (INIS)

    Shibasaki, Kiyoto

    2007-01-01

    Solar atmosphere is filled with plasma and magnetic field. Activities in the atmosphere are due to plasma instabilities in the magnetic field. To understand the physical mechanisms of activities / instabilities, it is necessary to know the physical conditions of magnetized plasma, such as temperature, density, magnetic field, and their spatial structures and temporal developments. Multi-wavelength imaging is essential for this purpose. Imaging observations of the Sun at microwave, X-ray, EUV and optical ranges are routinely going on. Due to free exchange of original data among solar physics and related field communities, we can easily combine images covering wide range of spectrum. Even under such circumstances, we still do not understand the cause of activities in the solar atmosphere well. The current standard model of solar activities is based on magnetic reconnection: release of stored magnetic energy by reconnection is the cause of solar activities on the Sun such as solar flares. However, recent X-ray, EUV and microwave observations with high spatial and temporal resolution show that dense plasma is involved in activities from the beginning. Based on these observations, I propose a high-beta model of solar activities, which is very similar to high-beta disruptions in magnetically confined fusion experiments. (author)

  7. Periodic Recurrence Patterns In X-Ray Solar Flare Appearances

    Science.gov (United States)

    Gyenge, N.; Erdélyi, R.

    2018-06-01

    The temporal recurrence of micro-flare events is studied for a time interval before and after of major solar flares. Our sample is based on the X-ray flare observations by the Geostationary Operational Environmental Satellite (GOES) and Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI). The analyzed data contain 1330/301 M-class and X-class GOES/RHESSI energetic solar flares and 4062/4119 GOES/RHESSI micro-flares covering the period elapse since 2002. The temporal analysis of recurrence, by Fast Fourier Transform, of the micro-flares, shows multiple significant periods. Based on the GOES and RHESSI data, the temporal analysis also demonstrates that multiple periods manifest simultaneously in both statistical samples without any significant shift over time. In the GOES sample, the detected significant periods are: 11.33, 5.61, 3.75, 2.80, and 2.24 minutes. The RHESSI data show similar significant periods at 8.54, 5.28, 3.66, 2.88, and 2.19 minutes. The periods are interpreted as signatures of standing oscillations, with the longest period (P 1) being the fundamental and others being higher harmonic modes. The period ratio of the fundamental and higher harmonics (P 1/P N ) is also analyzed. The standing modes may be signatures of global oscillations of the entire solar atmosphere encompassing magnetized plasma from the photosphere to the corona in active regions.

  8. Resolving the origin of the diffuse soft X-ray background

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Randall K.; Foster, Adam R.; Edgar, Richard J.; Brickhouse, Nancy S. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge MA 02138 (United States)

    2014-05-20

    The ubiquitous diffuse soft (1/4 keV) X-ray background was one of the earliest discoveries of X-ray astronomy. At least some of the emission may arise from charge exchange between solar wind ions and neutral atoms in the heliosphere, but no detailed models have been fit to the available data. Here, we report on a new model for charge exchange in the solar wind, which, when combined with a diffuse hot plasma component, filling the Local Cavity provides a good fit to the only available high-resolution soft X-ray and extreme ultraviolet spectra using plausible parameters for the solar wind. The implied hot plasma component is in pressure equilibrium with the local cloud that surrounds the solar system, creating for the first time a self-consistent picture of the local interstellar medium.

  9. A New High-sensitivity solar X-ray Spectrophotometer SphinX:early operations and databases

    Science.gov (United States)

    Gburek, Szymon; Sylwester, Janusz; Kowalinski, Miroslaw; Siarkowski, Marek; Bakala, Jaroslaw; Podgorski, Piotr; Trzebinski, Witold; Plocieniak, Stefan; Kordylewski, Zbigniew; Kuzin, Sergey; Farnik, Frantisek; Reale, Fabio

    The Solar Photometer in X-rays (SphinX) is an instrument operating aboard Russian CORONAS-Photon satellite. A short description of this unique instrument will be presented and its unique capabilities discussed. SphinX is presently the most sensitive solar X-ray spectrophotometer measuring solar spectra in the energy range above 1 keV. A large archive of SphinX mea-surements has already been collected. General access to these measurements is possible. The SphinX data repositories contain lightcurves, spectra, and photon arrival time measurements. The SphinX data cover nearly continuously the period since the satellite launch on January 30, 2009 up to the end-of November 2009. Present instrument status, data formats and data access methods will be shown. An overview of possible new science coming from SphinX data analysis will be discussed.

  10. A study of solar flare energy transport based on coordinated H-alpha and X-ray observations

    International Nuclear Information System (INIS)

    Canfield, R.C.; Wulser, J.; Zarro, D.M.; Dennis, B.R.

    1991-01-01

    The temporal evolution of the ratio between H-alpha to nonthermal hard X-ray emission was investigated using coordinated H-alpha and hard- and soft-X-ray observations of five solar flares (on May 7, June 23, June 24, and June 25, 1980 and on April 30, 1985). These observations were used to estimate the emitted flare energy flux F(H-alpha) in H-alpha, the flux of F(2O) energy deposited by nonthermal electrons with energies above 20 keV, and the pressure p(c) of soft X-ray-emitting plasma as functions of time during the impulsive phase of each flare. It was found that the F(H-alpha)/F(2O) ratio shows a power-law dependence on F(2O), with a slope that differs slightly from that predicted by the static thick-target model of solar transport. Results also indicate that the power-law dependence is modified by hydrostatic pressure effects. 25 refs

  11. High spectral resolution measurements of a solar flare hard X-ray burst

    International Nuclear Information System (INIS)

    Lin, R.P.; Schwartz, R.A.; NASA, Goddard Space Flight Center, Greenbelt, MD)

    1987-01-01

    Observations are reported of an intense solar flare hard X-ray burst on June 27, 1980, made with a balloon-borne array of liquid nitrogen-cooled Ge detector which provided unprecedented spectral resolution (no more than 1 keV FWHM). The hard X-ray spectra throughout the impulsive phase burst fitted well to a double power-law form, and emission from an isothermal 0.1-1 billion K plasma can be specifically excluded. The temporal variations of the spectrum indicate that the hard X-ray burst is made up of two superposed components: individual spikes lasting about 3-15 sec, which have a hard spectrum and a break energy of 30-65 keV; and a slowly varying component characterized by a soft spectrum with a constant low-energy slope and a break energy which increases from 25 kev to at least 100 keV through the event. The double power-law shape indicates that DC electric field acceleration, similar to that occurring in the earth's auroral zone, may be the source of the energetic electrons which produce the hard X-ray emission. 39 references

  12. Great microwave bursts and hard X-rays from solar flares

    International Nuclear Information System (INIS)

    Wiehl, H.J.; Batchelor, D.A.; Crannell, C.J.; Dennis, B.R.; Price, P.N.

    1983-06-01

    The microwave and hard X-ray charateristics of 13 solar flares that produced microwave fluxes greater than 500 Solar Flux Units were analyzed. These Great Microwave Bursts were observed in the frequency range from 3 to 35 GHz at Berne, and simultaneous hard X-ray observations were made in the energy range from 30 to 500 keV with the Hard X-Ray Burst Spectrometer on the Solar Maximum Mission spacecraft. The principal aim of this analysis is to determine whether or not the same distribution of energetic electrons can explain both emissions. Correlations were found between respective temporal characteristics and, for the first time, between microwave and hard X-ray spectral characteristics. A single-temperature and a multi-temperature model from the literature were tested for consistency with the coincident X-ray and microwave spectra at microwave burst maximum. Four events are inconsistent with both of the models tested, and neither of the models attempts to explain the high-frequency part of the microwave spectrum. A model in which the emissions above and below the peak frequency originate in two different parts of a diverging magnetic loop is proposed. With this model the entire microwave spectrum of all but one of the events is explained

  13. Plasma x-ray radiation source.

    Science.gov (United States)

    Popkov, N F; Kargin, V I; Ryaslov, E A; Pikar', A S

    1995-01-01

    This paper gives the results of studies on a plasma x-ray source, which enables one to obtain a 2.5-krad radiation dose per pulse over an area of 100 cm2 in the quantum energy range from 20 to 500 keV. Pulse duration is 100 ns. Spectral radiation distributions from a diode under various operation conditions of a plasma are obtained. A Marx generator served as an initial energy source of 120 kJ with a discharge time of T/4 = 10-6 s. A short electromagnetic pulse (10-7 s) was shaped using plasma erosion opening switches.

  14. GOES-12 Solar X-ray Imager Archive

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The GOES Solar X-ray Imager is integrated into the GOES-12 satellite, whose primary mission is to provide Earth-weather monitoring. The SXI is operated by NOAA's...

  15. Solar X-rays from Axions: Rest-Mass Dependent Signatures

    CERN Document Server

    Zioutas, Konstantin; Semertzidis, Yannis; Papaevangelou, Thomas; Gardikiotis, Antonios; Dafni, Theopisti; Anastassopoulos, Vassilis

    2010-01-01

    The spectral shape of solar X-rays is a power law. The more active the Sun is, the less steep the distribution. This behaviour can be explained by axion regeneration to X-rays occurring ~400km deep into the photosphere. Their down-comptonization reproduces the measured spectral shape, pointing at axions with rest mass m_a~17 meV/c2, without contradicting astrophysical-laboratory limits. Directly measured soft X-ray spectra from the extremely quiet Sun during 2009 (SphinX mission), though hitherto overlooked, fitt the axion scenario.

  16. Time-resolved x-ray line diagnostics of laser-produced plasmas

    International Nuclear Information System (INIS)

    Kauffman, R.L.; Matthews, D.L.; Kilkenny, J.D.; Lee, R.W.

    1982-01-01

    We have examined the underdense plasma conditions of laser irradiated disks using K x-rays from highly ionized ions. A 900 ps laser pulse of 0.532 μm light is used to irradiate various Z disks which have been doped with low concentrations of tracer materials. The tracers whose Z's range from 13 to 22 are chosen so that their K x-ray spectrum is sensitive to typical underdense plasma temperatures and densities. Spectra are measured using a time-resolved crystal spectrograph recording the time history of the x-ray spectrum. A spatially-resolved, time-integrated crystal spectrograph also monitors the x-ray lines. Large differences in Al spectra are observed when the host plasma is changed from SiO 2 to PbO or In. Spectra will be presented along with preliminary analysis of the data

  17. X-ray Imaging and preliminary studies of the X-ray self-emission from an innovative plasma-trap based on the Bernstein waves heating mechanism

    Science.gov (United States)

    Caliri, C.; Romano, F. P.; Mascali, D.; Gammino, S.; Musumarra, A.; Castro, G.; Celona, L.; Neri, L.; Altana, C.

    2013-10-01

    Electron Cyclotron Resonance Ion Sources (ECRIS) are based on ECR heated plasmas emitting high fluxes of X-rays. Here we illustrate a pilot study of the X-ray emission from a compact plasma-trap in which an off-resonance microwave-plasma interaction has been attempted, highlighting a possible Bernstein-Waves based heating mechanism. EBWs-heating is obtained via the inner plasma EM-to-ES wave conversion and enables to reach densities much larger than the cut-off ones. At LNS-INFN, an innovative diagnostic technique based on the design of a Pinhole Camera (PHC) coupled to a CCD device for X-ray Imaging of the plasma (XRI) has been developed, in order to integrate X-ray traditional diagnostics (XRS). The complementary use of electrostatic probes measurements and X-ray diagnostics enabled us to gain knowledge about the high energy electrons density and temperature and about the spatial structure of the source. The combination of the experimental data with appropriate modeling of the plasma-source allowed to estimate the X-ray emission intensity in different energy domains (ranging from EUV up to Hard X-rays). The use of ECRIS as X-ray source for multidisciplinary applications, is now a concrete perspective due to the intense fluxes produced by the new plasma heating mechanism.

  18. Soft X-ray imaging techniques for calculating the Earth's dayside boundaries

    Science.gov (United States)

    Connor, Hyunju; Kuntz, Kip; Sibeck, David; Collier, Michael; Aryan, Homayon; Branduardi-Raymont, Graziella; Collado-Vega, Yaireska; Porter, Frederick; Purucker, Michael; Snowden, Steven; Raeder, Joachim; Thomas, Nicholas; Walsh, Brian

    2016-04-01

    Charged particles and neutral atoms exchange electrons in many space plasma venues. Soft X-rays are emitted when highly charged solar wind ions, such as C6+. O7+, and Fe13+, interact with Hydrogen and Helium atoms. Soft X-ray images can be a powerful technique to remotely probe the plasma and neutral density structures created when the solar wind interacts with planetary exospheres, such as those at the Earth, Moon, Mars, Venus, and comets. The recently selected ESA-China joint spacecraft mission, "Solar wind - Magnetosphere - Ionosphere Link Explorer (SMILE)" will have a soft X-ray imager on board and provide pictures of the Earth's dayside system after its launch in 2021. In preparation for this future mission, we simulate soft X-ray images of the Earth's dayside system, using the OpenGGCM global magnetosphere MHD model and the Hodges model of the Earth's exosphere. Then, we discuss techniques to determine the location of the Earth's dayside boundaries (bow shock and magnetopause) from the soft X-ray images.

  19. Analysis of the Relationship Between the Solar X-Ray Radiation Intensity and the D-Region Electron Density Using Satellite and Ground-Based Radio Data

    Science.gov (United States)

    Nina, Aleksandra; Čadež, Vladimir M.; Bajčetić, Jovan; Mitrović, Srdjan T.; Popović, Luka Č.

    2018-04-01

    Increases in the X-ray radiation that is emitted during a solar X-ray flare induce significant changes in the ionospheric D region. Because of the numerous complex processes in the ionosphere and the characteristics of the radiation and plasma, the causal-consequential relationship between the X-ray radiation and ionospheric parameters is not easily determined. In addition, modeling the ionospheric D-region plasma parameters is very difficult because of the lack of data for numerous time- and space-dependent physical quantities. In this article we first give a qualitative analysis of the relationship between the electron density and the recorded solar X-ray intensity. After this, we analyze the differences in the relationships between the D-region response and various X-ray radiation properties. The quantitative study is performed for data observed on 5 May 2010 in the time period between 11:40 UT - 12:40 UT when the GOES 14 satellite detected a considerable X-ray intensity increase. Modeling the electron density is based on characteristics of the 23.4 kHz signal emitted in Germany and recorded by the receiver in Serbia.

  20. Anomalous x-ray radiation of beam plasma

    International Nuclear Information System (INIS)

    Dimitrov, S.K.; Zavyalov, M.A.; Mikhin, S.G.; Tarasenkov, V.A.; Telkovskij, V.G.; Khrabrov, V.A.

    1985-01-01

    The properties of non-equilibrium stationary plasma under the conditions of the planned plasma-chemical reactors based on beam-plasma discharge were investigated. The x-ray spectrum of the beam-plasma was measured and anomalous spectral properties were analyzed. Starting with some critical pressure the anomalous radiation was added to the classical bremsstrahlung spectrum. The occurrence of anomalous radiation can be used to diagnose the condition of beam transportation in such systems. (D.Gy.)

  1. Comparison of nonflare solar soft x ray flux with 10.7-cm radio flux

    International Nuclear Information System (INIS)

    Donnelly, R.F.

    1982-01-01

    The similarities and differences of the nonflare solar 1- to 8-A X ray flux and the daily 10.7-cm Ottawa solar radio flux are examined. The radio flux is shown to be much less sensitive than the soft X ray flux on the average to the coronal emission of active regions located near or beyond the solar chromospheric limb relative to regions near the center of the solar disk. This is caused by the solar soft X ray emission's being optically thin while much of the 10.7-cm active region emission is from optical depths of tauapprox.1. The radio flux includes a large quiet sun flux which is emitted mostly from the tenuous chromosphere-corona transition region (Tapprox.10 4 --10 6 0 K) and partly from the cooler portions of the quiet corona Tapprox.1.5 x 10 6 0 K. Conversely, the solar soft X ray flux has a very small quiet sun component

  2. Quantitative relationship between VLF phase deviations and 1-8 A solar X-ray fluxes during solar flares

    Energy Technology Data Exchange (ETDEWEB)

    Muraoka, Y; Murata, H; Sato, T [Hyogo Coll. Of Medicine (Japan). Dept. of Physics

    1977-07-01

    An attempt is made to investigate the quantitative relationship between VLF phase deviations in SPA (sudden phase anomalies) events and associated solar X-ray fluxes in the 1 to 8 A band during solar flares. The phase deviations (..delta..phi) of the 18.6 kHz VLF wave transmitted from NLK, USA are used in this analysis which were recorded at Nishinomiya, Japan during the period June 1974 to May 1975. The solar X-ray fluxes (F/sub 0/) in the 1 to 8 A band are estimated from fsub(min) variations using the empirical expression given by Sato (J.Geomag.Geoelectr.;27: 95(1975)), because no observed data were available on the 1 to 8 a X-ray fluxes during the period of the VLF observation. The result shows that the normalized phase variation, ..delta..phi/coschisub(min), where chisub(min) represents the minimum solar zenith angle on the VLF propagation path, increases with increasing logF/sub 0/. A theoretical explanation for this is presented assuming that enhanced ionizations produced in the lower ionosphere by a monochromatic solar X-ray emission are responsible for the VLF phase deviations. Also it is found that a threshold X-ray flux to produce a detectable SPA effect is approximately 1.5 x 10/sup -3/ cm/sup -2/ sec/sup -1/ in the 1 to 8 a band.

  3. Space- and time-resolved diagnostics of soft x-ray emission from laser plasmas

    International Nuclear Information System (INIS)

    Richardson, M.C.; Jaanimagi, P.A.; Chen, H.

    1988-01-01

    The analysis of soft x-ray emission from plasmas created by intense short-wavelength laser radiation can provide much useful information on the density, temperature and ionization distribution of the plasma. Until recently, limitations of sensitivity and the availability of suitable x-ray optical elements have restricted studies of soft x-ray emission from laser plasmas. In this paper, the authors describe novel instrumentation which provides high sensitivity in the soft x-ray spectrum with spatial and temporal resolution in the micron and picosecond ranges respectively. These systems exploit advances made in soft x-ray optic and electro-optic technology. Their application in current studies of laser fusion, x-ray lasers, and high density atomic physics are discussed

  4. Plasma dynamics above solar flare soft x-ray loop tops

    Energy Technology Data Exchange (ETDEWEB)

    Doschek, G. A.; Warren, H. P. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); McKenzie, D. E. [Montana State University, Bozeman, MT 59717 (United States)

    2014-06-10

    We measure non-thermal motions in flare loop tops and above the loop tops using profiles of highly ionized spectral lines of Fe XXIV and Fe XXIII formed at multimillion-degree temperatures. Non-thermal motions that may be due to turbulence or multiple flow regions along the line of sight are extracted from the line profiles. The non-thermal motions are measured for four flares seen at or close to the solar limb. The profile data are obtained using the Extreme-ultraviolet Imaging Spectrometer on the Hinode spacecraft. The multimillion-degree non-thermal motions are between 20 and 60 km s{sup –1} and appear to increase with height above the loop tops. Motions determined from coronal lines (i.e., lines formed at about 1.5 MK) tend to be smaller. The multimillion-degree temperatures in the loop tops and above range from about 11 MK to 15 MK and also tend to increase with height above the bright X-ray-emitting loop tops. The non-thermal motions measured along the line of sight, as well as their apparent increase with height, are supported by Solar Dynamics Observatory Atmospheric Imaging Assembly measurements of turbulent velocities in the plane of the sky.

  5. X-ray spectroscopic study of high-temperature plasmas by curved crystal spectrometer

    International Nuclear Information System (INIS)

    Morita, Shigeru.

    1983-07-01

    Extensive studies have been carried out on the structure of X-ray spectra from the highly stripped ions of first transition elements and their behavior in high temperature plasma, using a high resolution crystal spectrometer. Calculation was made on the design and the use of a curved crystal spectrometer for plasma diagnostics. A Johann type crystal spectrometer for measuring X-ray lines was constructed on the basis of the calculation. The characteristics of curved crystals of LiF, Ge and quartz used for the measurement of Kα lines from first transition elements were investigated. Vacuum sparks have been formed for producing high temperature plasma which emits X-ray lines from highly stripped ions. Two different structures of vacuum spark plasma were shown, that is, thermalized point plasma and extended plasma associated with non-thermal electrons. The X-ray lines from the extended plasma, those associated with the K shell from the point plasma and the Kα lines of Ti through Zn from the point plasma have been observed. (Kako, I.)

  6. Atomic Layer Deposition Re Ective Coatings For Future Astronomical Space Telescopes And The Solar Corona Viewed Through The Minxss (Miniature X-Ray Solar Spectrometer) Cubesats

    Science.gov (United States)

    Moore, Christopher Samuel

    2017-11-01

    Advances in technology and instrumentation open new windows for observing astrophysical objects. The first half of my dissertation involves the development of atomic layer deposition (ALD) coatings to create high reflectivity UV mirrors for future satellite astronomical telescopes. Aluminum (Al) has intrinsic reflectance greater than 80% from 90 – 2,000 nm, but develops a native aluminum oxide (Al2O3) layer upon exposure to air that readily absorbs light below 250 nm. Thus, Al based UV mirrors must be protected by a transmissive overcoat. Traditionally, metal-fluoride overcoats such as MgF2 and LiF are used to mitigate oxidation but with caveats. We utilize a new metal fluoride (AlF3) to protect Al mirrors deposited by ALD. ALD allows for precise thickness control, conformal and near stoichiometric thin films. We prove that depositing ultra-thin ( 3 nm) ALD ALF3 to protect Al mirrors after removing the native oxide layer via atomic layer etching (ALE) enhances the reflectance near 90 nm from 5% to 30%.X-ray detector technology with high readout rates are necessary for the relatively bright Sun, particularly during large flares. The hot plasma in the solar corona generates X-rays, which yield information on the physical conditions of the plasma. The second half of my dissertation includes detector testing, characterization and solar science with the Miniature X-ray Solar Spectrometer (MinXSS) CubeSats. The MinXSS CubeSats employ Silicon Drift Diode (SDD) detectors called X123, which generate full sun spectrally resolved ( 0.15 FWHM at 5.9 keV) measurements of the sparsely measured, 0.5 – 12 keV range. The absolute radiometric calibration of the MinXSS instrument suite was performed at the National Institute for Standards and Technology (NIST) Synchrotron Ultraviolet Radiation Facility (SURF) and spectral resolution determined from radioactive sources. I used MinXSS along with data from the Geostationary Operational Environmental Satellites (GOES), Reuven Ramaty

  7. The x-ray laser as a tool for imaging plasmas

    International Nuclear Information System (INIS)

    Libby, S.B.; Da Silva, L.B.; Barbee, T.W. Jr.

    1995-07-01

    The x-ray laser is now being used at LLNL as a tool for measuring the behaviors of hot dense plasmas. In particular, we have used the 155 Angstrom yttrium laser to study transient plasmas by both radiography and moire deflectrometry. These techniques have been used to probe long scale length plasmas at electron densities exceeding 10 22 cm -3 . Recent advances in multilayer technology have made it possible to directly image ion densities in directly driven thin foils to an accuracy of 1--2 μm. In addition, we have constructed an x-ray laser Mach-Zehnder interferometer using multilayer beam-splitters. This interferometer yields direct 2D projections of electron densities in plasmas with micron spatial resolution. In addition, this interferometer can be used to measure spectral line shapes to high accuracy. Among the subject plasmas under study are laser irradiated planar targets, gold hohlraums, and x-ray lasers themselves

  8. A Compressed Sensing-based Image Reconstruction Algorithm for Solar Flare X-Ray Observations

    Energy Technology Data Exchange (ETDEWEB)

    Felix, Simon; Bolzern, Roman; Battaglia, Marina, E-mail: simon.felix@fhnw.ch, E-mail: roman.bolzern@fhnw.ch, E-mail: marina.battaglia@fhnw.ch [University of Applied Sciences and Arts Northwestern Switzerland FHNW, 5210 Windisch (Switzerland)

    2017-11-01

    One way of imaging X-ray emission from solar flares is to measure Fourier components of the spatial X-ray source distribution. We present a new compressed sensing-based algorithm named VIS-CS, which reconstructs the spatial distribution from such Fourier components. We demonstrate the application of the algorithm on synthetic and observed solar flare X-ray data from the Reuven Ramaty High Energy Solar Spectroscopic Imager satellite and compare its performance with existing algorithms. VIS-CS produces competitive results with accurate photometry and morphology, without requiring any algorithm- and X-ray-source-specific parameter tuning. Its robustness and performance make this algorithm ideally suited for the generation of quicklook images or large image cubes without user intervention, such as for imaging spectroscopy analysis.

  9. A Compressed Sensing-based Image Reconstruction Algorithm for Solar Flare X-Ray Observations

    Science.gov (United States)

    Felix, Simon; Bolzern, Roman; Battaglia, Marina

    2017-11-01

    One way of imaging X-ray emission from solar flares is to measure Fourier components of the spatial X-ray source distribution. We present a new compressed sensing-based algorithm named VIS_CS, which reconstructs the spatial distribution from such Fourier components. We demonstrate the application of the algorithm on synthetic and observed solar flare X-ray data from the Reuven Ramaty High Energy Solar Spectroscopic Imager satellite and compare its performance with existing algorithms. VIS_CS produces competitive results with accurate photometry and morphology, without requiring any algorithm- and X-ray-source-specific parameter tuning. Its robustness and performance make this algorithm ideally suited for the generation of quicklook images or large image cubes without user intervention, such as for imaging spectroscopy analysis.

  10. Pulsed x-ray generation from a plasma focus device

    International Nuclear Information System (INIS)

    Zambra, M; Bruzzone, H; Sidelnikov, Y; Kies, W; Moreno, C; Sylvester, G; Silva, P; Moreno, J; Soto, L

    2003-01-01

    Dynamical pinches coupled to electrodes like the dense Z-pinch or the dense plasma focus have been intensively studied in the last four decades for their high fusion efficiency and their application potential. Though the expectations of the eighties of the last century, scaling these pinches up to fusion reactors, did not come true, the development of fast and powerful experiments resulted in new insights in pinch physics and paved the way for developing compact dynamical pinches as pulsed neutron and X-radiation sources for many applications. There is a permanent and growing interest in the research community for understanding and determining the generation properties of X-rays, neutrons and charged particles emitted from a high-temperature high-density plasmas, especially in the plasma focus configuration. The Plasma Physics and Plasma Technology Group of the CCHEN has developed the SPEED4 fast-plasma focus device, in collaboration with the Plasma Physics Group of the Dusseldorf University, in order to perform experimental studies such as X-ray and neutron emission, and electron and ion beam characterization (author)

  11. The possible effect of solar soft X rays on thermospheric nitric oxide

    International Nuclear Information System (INIS)

    Siskind, D.E.; Barth, C.A.; Cleary, D.D.

    1990-01-01

    A rocket measurement of thermospheric nitric oxide (NO) is used to evaluate the production of odd nitrogen by solar soft X rays (18-50 angstrom). The rocket observation was performed over White Sands Missile Range on November 9, 1981, at 1500 LT for solar maximum conditions (F10.7 = 233). The peak observed NO density was 6.3 x 10 7 cm -3 at 102 km. A photochemical model which included soft X rays was used for comparison with the data. The soft X rays create photoelectrons which lead to enhanced ionization of N 2 and thus increased odd nitrogen production. A good fit to the data was achieved using a soft X ray flux of 0.75 erg cm -2 s -1

  12. X-ray Heating and Electron Temperature of Laboratory Photoionized Plasmas

    Science.gov (United States)

    Mancini, Roberto; Lockard, Tom; Mayes, Daniel C.; Loisel, Guillaume; Bailey, James E.; Rochau, Gregory; Abdallah, J.; Golovkin, I.

    2018-06-01

    In separate experiments performed at the Z facility of Sandia National Laboratories two different samples were employed to produce and characterize photoionized plasmas. One was a gas cell filled with neon, and the other was a thin silicon layer coated with plastic. Both samples were driven by the broadband x-ray flux produced at the collapse of a wire array z-pinch implosion. Transmission spectroscopy of a narrowband portion of the x-ray flux was used to diagnose the charge state distribution, and the electron temperature was extracted from a Li-like ion level population ratio. To interpret the temperature measurement, we performed Boltzmann kinetics and radiation-hydrodynamic simulations. We found that non-equilibrium atomic physics and the coupling of the radiation flux to the atomic level population kinetics play a critical role in modeling the x-ray heating of photoionized plasmas. In spite of being driven by similar x-ray drives, differences of ionization and charged state distributions in the neon and silicon plasmas are reflected in the plasma heating and observed electron temperatures.This work was sponsored in part by DOE Office of Science Grant DE-SC0014451, and the Z Facility Fundamental Science Program of SNL.

  13. Cosmic and solar gamma-ray x-ray and particle measurements from high altitude balloons in Antarctica

    International Nuclear Information System (INIS)

    Lin, R.P.

    1990-01-01

    For measurements of cosmic and solar gamma-rays, hard X-rays, and particles, Antarctica offers the potential for very long, 10--20 day, continuous, twenty-four-hour-a-day observations, with balloon flights circling the South Pole during austral summer. For X-ray/gamma-ray sources at high south latitude the overlying atmosphere is minimized, and for cosmic ray measurements the low geomagnetic cutoff permits entry of low rigidity particles. The first Antarctic flight of a heavy (∼2400 lb.) payload on a large (11.6x10 6 cu. ft.) balloon took place in January, 1988, to search for the gamma-ray lines of 56 Co produced in the new supernova SN 1987A in the Large Magellanic Cloud. The long duration balloon flights presently planned from Antarctica include those for further gamma-ray/hard X-ray studies of SN 1987A and for the NASA Max '91 program for solar flare studies

  14. Nuclear Malaysia Plasma Focus Device as a X-ray Source For Radiography Applications

    International Nuclear Information System (INIS)

    Rokiah Mohd Sabri; Abdul Halim Baijan; Siti Aiasah Hashim; Mohd Rizal Mohd Chulan; Wah, L.K.; Mukhlis Mokhtar; Azaman Ahmad; Rosli Che Ros

    2013-01-01

    A 3.375 kJ plasma focus is designed to operate at 13.5 kV for the purpose of studying x-ray source for radiography in Argon discharge. X-rays is detected by using x-ray film from the mammography radiographic plate. The feasibility of the plasma focus as a high intensity flash x-ray source for good contrast in radiography image is presented. (author)

  15. Generation of relativistic electron bunches in plasma synchrotron Gyrac-x for hard x-ray production

    International Nuclear Information System (INIS)

    Andreev, V.V.; Umnov, A.M.

    2000-01-01

    Experiment performed on plasma synchrotron Gyrac-X operating on synchrotron gyromagnetic autoresonance (SGA) is described. Gyrac-X is a compact plasma x-ray source in which kinetic energy of relativistic electrons obtained under SGA converts into x-ray by falling e-bunches on to a heavy metal target. The plasma synchrotron acts in a regime of a magnetic field pulse packet under constant level of microwave power. Experiments and numerical modeling of the process showed that such a regime allowed obtaining dense short lived relativistic electron bunches with average electron energy of 500 keV - 4.5 MeV. Parameters of the relativistic electron bunch (energy, density and volume) and dynamics of the electron bunches can be controlled by varying the parameters of the SGA process. Possibilities of x-ray intensity increase are also discussed

  16. Irradiation of intense characteristic x-rays from weakly ionized linear molybdenum plasma

    International Nuclear Information System (INIS)

    Sato, Eiichi; Hayasi, Yasuomi

    2003-01-01

    In the plasma flash x-ray generator, a high-voltage main condenser of approximately 200 nF is charged up to 55 kV by a power supply, and electric charges in the condenser are discharged to an x-ray tube after triggering the cathode electrode. The flash x-rays are then produced. The x-ray tube is a demountable triode that is connected to a turbo molecular pump with a pressure of approximately 1 mPa. As electron flows from the cathode electrode are roughly converged to a rod molybdenum target of 2.0 mm in diameter by the electric field in the x-ray tube, weakly ionized linear plasma, which consists of molybdenum ions and electrons, forms by target evaporation. At a charging voltage of 55 kV, the maximum tube voltage was almost equal to the charging voltage of the main condenser, and the peak current was about 20 kA. When the charging voltage was increased, the linear plasma formed, and the K-series characteristic x-ray intensities increased. The K lines were quite sharp and intense, and hardly any bremsstrahlung rays were detected. The x-ray pulse widths were approximately 700 ns, and the time-integrated x-ray intensity had a value of approximately 35 μC/kg at 1.0 m from the x-ray source with a charging voltage of 50 kV. (author)

  17. X-ray Synchrotron Radiation in a Plasma Wiggler

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shuoquin; /UCLA /SLAC, SSRL

    2005-09-27

    A relativistic electron beam can radiate due to its betatron motion inside an ion channel. The ion channel is induced by the electron bunch as it propagates through an underdense plasma. In the theory section of this thesis the formation of the ion channel, the trajectories of beam electrons inside the ion channel, the radiation power and the radiation spectrum of the spontaneous emission are studied. The comparison between different plasma wiggler schemes is made. The difficulties in realizing stimulated emission as the beam traverses the ion channel are investigated, with particular emphasis on the bunching mechanism, which is important for the ion channel free electron laser. This thesis reports an experiment conducted at the Stanford Linear Accelerator Center (SLAC) to measure the betatron X-ray radiations for the first time. They first describe the construction and characterization of the lithium plasma source. In the experiment, the transverse oscillations of the SLAC 28.5 GeV electron beam traversing through a 1.4 meter long lithium plasma source are clearly seen. These oscillations lead to a quadratic density dependence of the spontaneously emitted betatron X-ray radiation. The divergence angle of the X-ray radiation is measured. The absolute photon yield and the spectral brightness at 14.2 KeV photon energy are estimated and seen to be in reasonable agreement with theory.

  18. Synchrotron X-ray imaging applied to solar photovoltaic silicon

    International Nuclear Information System (INIS)

    Lafford, T A; Villanova, J; Plassat, N; Dubois, S; Camel, D

    2013-01-01

    Photovoltaic (PV) cell performance is dictated by the material of the cell, its quality and purity, the type, quantity, size and distribution of defects, as well as surface treatments, deposited layers and contacts. A synchrotron offers unique opportunities for a variety of complementary X-ray techniques, given the brilliance, spectrum, energy tunability and potential for (sub-) micron-sized beams. Material properties are revealed within in the bulk and at surfaces and interfaces. X-ray Diffraction Imaging (X-ray Topography), Rocking Curve Imaging and Section Topography reveal defects such as dislocations, inclusions, misorientations and strain in the bulk and at surfaces. Simultaneous measurement of micro-X-Ray Fluorescence (μ-XRF) and micro-X-ray Beam Induced Current (μ-XBIC) gives direct correlation between impurities and PV performance. Together with techniques such as microscopy and Light Beam Induced Current (LBIC) measurements, the correlation between structural properties and photovoltaic performance can be deduced, as well as the relative influence of parameters such as defect type, size, spatial distribution and density (e.g [1]). Measurements may be applied at different stages of solar cell processing in order to follow the evolution of the material and its properties through the manufacturing process. Various grades of silicon are under study, including electronic and metallurgical grades in mono-crystalline, multi-crystalline and mono-like forms. This paper aims to introduce synchrotron imaging to non-specialists, giving example results on selected solar photovoltaic silicon samples.

  19. Intensity-dependent resonant transmission of x-rays in solid-density aluminum plasma

    Science.gov (United States)

    Cho, M. S.; Chung, H.-K.; Cho, B. I.

    2018-05-01

    X-ray free-electron lasers (XFELs) provide unique opportunities to generate and investigate dense plasmas. The absorption and transmission properties of x-ray photons in dense plasmas are important in characterizing the state of the plasmas. Experimental evidence shows that the transmission of x-ray photons through dense plasmas depends greatly on the incident XFEL intensity. Here, we present a detailed analysis of intensity-dependent x-ray transmission in solid-density aluminum using collisional-radiative population kinetics calculations. Reverse saturable absorption (RSA), i.e., an increase in x-ray absorption with intensity has been observed for photon energies below the K-absorption edge and in the intensity range of 1016-1017 W/cm2 for XFEL photons with 1487 eV. At higher intensities, a transition from RSA to saturable absorption (SA) is predicted; thus, the x-ray absorption decreases with intensity above a threshold value. For XFEL photon energies of 1501 eV and 1515 eV, the transition from RSA to SA occurs at XFEL intensities between 1017-1018 W/cm2. Electron temperatures are predicted to be in the range of 30-50 eV for the given experimental conditions. Detailed population kinetics of the charge states explains the intensity-dependent absorption of x-ray photons and the fast modulation of XFEL pulses for both RSA and SA.

  20. Time-resolved x-ray line diagnostics of laser-produced plasmas

    International Nuclear Information System (INIS)

    Kauffman, R.L.; Matthews, D.L.; Kilkenny, J.D.; Lee, R.W.

    1982-11-01

    We have examined the underdense plasma conditions of laser irradiated disks using K x-rays from highly ionized ions. A 900 ps laser pulse of 0.532 μm light is used to irradiate various Z disks which have been doped with low concentrations of tracer materials. The tracers, whose Z's range from 13 to 22, are chosen so that their K x-ray spectrum is sensitive to typical underdense plasma temperatures and densities. Spectra are measured using a time-resolved crystal spectrograph recording the time history of the x-ray spectrum. A spatially-resolved, time-integrated crystal spectrograph also monitors the x-ray lines. Large differences in Al spectra are observed when the host plasms is changed from SiO 2 to PbO or In. Spectra will be presented along with preliminary analysis of the data

  1. Solar X-ray Spectrometer (SOXS) Mission – Low Energy Payload ...

    Indian Academy of Sciences (India)

    Solar X-ray Spectrometer (SOXS)' mission, which was launched onboard GSAT-2 Indian spacecraft on 08 May 2003 by GSLV-D2 rocket to study the solar flares. The SOXS Low Energy Detector (SLD) payload was designed, developed and ...

  2. Spectral analysis of K-shell X-ray emission of magnesium plasma

    Indian Academy of Sciences (India)

    2014-02-06

    Feb 6, 2014 ... Spectral analysis of K-shell X-ray emission of magnesium plasma, produced by laser pulses of 45 fs duration, focussed up to an intensity of ∼1018 W cm-2, is carried out. The plasma conditions prevalent during the emission of X-ray spectrum were identified by comparing the experimental spectra with the ...

  3. Plasma heating in solar flares and their soft and hard X-ray emissions

    International Nuclear Information System (INIS)

    Falewicz, R.

    2014-01-01

    In this paper, the energy budgets of two single-loop-like flares observed in X-ray are analyzed under the assumption that nonthermal electrons (NTEs) are the only source of plasma heating during all phases of both events. The flares were observed by RHESSI and GOES on 2002 February 20 and June 2, respectively. Using a one-dimensional (1D) hydrodynamic code for both flares, the energy deposited in the chromosphere was derived applying RHESSI observational data. The use of the Fokker-Planck formalism permits the calculation of distributions of the NTEs in flaring loops and thus spatial distributions of the X-ray nonthermal emissions and integral fluxes for the selected energy ranges that were compared with the observed ones. Additionally, a comparative analysis of the spatial distributions of the signals in the RHESSI images was conducted for the footpoints and for all the flare loops in selected energy ranges with these quantities' fluxes obtained from the models. The best compatibility of the model and observations was obtained for the 2002 June 2 event in the 0.5-4 Å GOES range and total fluxes in the 6-12 keV, 12-25 keV, 20-25 keV, and 50-100 keV energy bands. Results of photometry of the individual flaring structures in a high energy range show that the best compliance occurred for the 2002 June 2 flare, where the synthesized emissions were at least 30% higher than the observed emissions. For the 2002 February 20 flare, synthesized emission is about four times lower than the observed one. However, in the low energy range the best conformity was obtained for the 2002 February 20 flare, where emission from the model is about 11% lower than the observed one. The larger inconsistency occurs for the 2002 June 2 solar flare, where synthesized emission is about 12 times greater or even more than the observed emission. Some part of these differences may be caused by inevitable flaws of the applied methodology, like by an assumption that the model of the flare is

  4. Plasma Heating in Solar Flares and their Soft and Hard X-Ray Emissions

    Science.gov (United States)

    Falewicz, R.

    2014-07-01

    In this paper, the energy budgets of two single-loop-like flares observed in X-ray are analyzed under the assumption that nonthermal electrons (NTEs) are the only source of plasma heating during all phases of both events. The flares were observed by RHESSI and GOES on 2002 February 20 and June 2, respectively. Using a one-dimensional (1D) hydrodynamic code for both flares, the energy deposited in the chromosphere was derived applying RHESSI observational data. The use of the Fokker-Planck formalism permits the calculation of distributions of the NTEs in flaring loops and thus spatial distributions of the X-ray nonthermal emissions and integral fluxes for the selected energy ranges that were compared with the observed ones. Additionally, a comparative analysis of the spatial distributions of the signals in the RHESSI images was conducted for the footpoints and for all the flare loops in selected energy ranges with these quantities' fluxes obtained from the models. The best compatibility of the model and observations was obtained for the 2002 June 2 event in the 0.5-4 Å GOES range and total fluxes in the 6-12 keV, 12-25 keV, 20-25 keV, and 50-100 keV energy bands. Results of photometry of the individual flaring structures in a high energy range show that the best compliance occurred for the 2002 June 2 flare, where the synthesized emissions were at least 30% higher than the observed emissions. For the 2002 February 20 flare, synthesized emission is about four times lower than the observed one. However, in the low energy range the best conformity was obtained for the 2002 February 20 flare, where emission from the model is about 11% lower than the observed one. The larger inconsistency occurs for the 2002 June 2 solar flare, where synthesized emission is about 12 times greater or even more than the observed emission. Some part of these differences may be caused by inevitable flaws of the applied methodology, like by an assumption that the model of the flare is

  5. Soft x-ray imaging system for measurement of noncircular tokamak plasmas

    International Nuclear Information System (INIS)

    Fonck, R.J.; Reusch, M.; Jaehnig, K.P.; Hulse, R.; Roney, P.

    1986-08-01

    A soft x-ray camera and image processing system has been constructed to provide measurements of the internal shape of high temperature tokamak plasmas. The camera consists of a metallic-foil-filtered pinhole aperture and a microchannel plate image intensifier/convertor which produces a visible image for detection by a CCD TV camera. A wide-angle tangential view of the toroidal plasma allows a single compact camera to view the entire plasma cross section. With Be filters 12 to 50 μm thick, the signal from the microchannel plate is produced mostly by nickel L-line emissions which orignate in the hot plasma core. The measured toroidal image is numerically inverted to produce a cross-sectional soft x-ray image of the plasma. Since the internal magnetic flux surfaces are usually isothermal and the nickel emissivity depends strongly on the local electron temperature, the x-ray emission contours reflect the shape of the magnetic surfaces in the plasma interior. Initial results from the PBX tokamak experiment show clear differences in internal plasma shapes for circular and bean-shaped discharges

  6. Solar Coronal Events with Extended Hard X-ray and Gamma-ray Emission

    Science.gov (United States)

    Hudson, H. S.

    2017-12-01

    A characteristic pattern of solar hard X-ray emission, first identified in SOL1969-03-31 by Frost & Dennis (1971) now has been linked to prolonged high-energy gamma-ray emission detected by the Fermi/LAT experiment, for example in SOL2014-09-01. The distinctive features of these events include flat hard X-ray spectra extending well above 100 keV, a characteristic pattern of time development, low-frequency gyrosynchrotron peaks, CME association, and gamma-rays identifiable with pion decay originating in GeV ions. The identification of these events with otherwise known solar structures nevertheless remains elusive, in spite of the wealth of imagery available from AIA. The quandary is that these events have a clear association with CMEs in the high corona, and yet the gamma-ray production implicates the photosphere itself. The vanishingly small loss cone in the nominal acceleration region makes this extremely difficult. I propose direct inward advection of a part of the SEP particle population, as created on closed field structures, as a possible resolution of this puzzle, and note that this requires retracting magnetic structures on long time scales following the flare itself.

  7. The Miniature X-ray Solar Spectrometer (MinXSS) CubeSats: instrument capabilities and early science analysis on the quiet Sun, active regions, and flares.

    Science.gov (United States)

    Moore, Christopher S.; Woods, Tom; Caspi, Amir; Dennis, Brian R.; MinXSS Instrument Team, NIST-SURF Measurement Team

    2018-01-01

    Detection of soft X-rays (sxr) from the Sun provide direct information on coronal plasma at temperatures in excess of ~1 MK, but there have been relatively few solar spectrally resolved measurements from 0.5 – 10. keV. The Miniature X-ray Solar Spectrometer (MinXSS) CubeSat is the first solar science oriented CubeSat mission flown for the NASA Science Mission Directorate, and has provided measurements from 0.8 -12 keV, with resolving power ~40 at 5.9 keV, at a nominal ~10 second time cadence. MinXSS design and development has involved over 40 graduate students supervised by professors and professionals at the University of Colorado at Boulder. Instrument radiometric calibration was performed at the National Institute for Standard and Technology (NIST) Synchrotron Ultraviolet Radiation Facility (SURF) and spectral resolution determined from radioactive X-ray sources. The MinXSS spectra allow for determining coronal abundance variations for Fe, Mg, Ni, Ca, Si, S, and Ar in active regions and during flares. Measurements from the first of the twin CubeSats, MinXSS-1, have proven to be consistent with the Geostationary Operational Environmental Satellite (GOES) 0.1 – 0.8 nm energy flux. Simultaneous MinXSS-1 and Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) observations have provided the most complete sxr spectral coverage of flares in recent years. These combined measurements are vital in estimating the heating flare loops by non-thermal accelerated electrons. MinXSS-1 measurements have been combined with the Hinode X-ray Telescope (XRT) and Solar Dynamics Observatory Atmospheric Imaging Assembly (SDO-AIA) to further constrain the coronal temperature distribution during quiescent times. The structure of the temperature distribution (especially for T > 5 MK) is important for deducing heating processes in the solar atmosphere. MinXSS-1 observations yield some of the tightest constraints on the high temperature component of the coronal plasma, in the

  8. Characteristics of hard X-ray double sources in impulsive solar flares

    Science.gov (United States)

    Sakao, T.; Kosugi, T.; Masuda, S.; Yaji, K.; Inda-Koide, M.; Makishima, K.

    1996-01-01

    Imaging observations of solar flare hard X-ray sources with the Hard X-ray Telescope (HXT) aboard the Yohkoh satellite have revealed that hard X-ray emissions (greater than 30 ke V) originate most frequently from double sources. The double sources are located on both sides of the magnetic neutral line, suggesting that the bulk of hard X-rays is emitted from footpoints of flaring magnetic loops. We also found that hard X-rays from the double sources are emitted simultaneously within a fraction of second and that the weaker source tends to be located in the stronger magnetic field region, showing a softer spectrum. Physcial implications on the observed characteristics of the hard X-ray double sources are discussed.

  9. Target surface structure effects on x-ray generation from laser produced plasma

    Energy Technology Data Exchange (ETDEWEB)

    Nishikawa, Tadashi; Nakano, Hidetoshi; Uesugi, Naoshi [NTT Basic Research Laboratories, Atsugi, Kanagawa (Japan)

    2000-03-01

    We demonstrated two different methods to increase the x-ray conversion efficiency of laser-produced plasma by modifying the target surface structure. One way is making a rectangular groove on a target surface and confining a laser-produced plasma in it. By the plasma collision process, a time and wavelength (4-10 nm) integrated soft x-ray fluence enhancement of 35 times was obtained at a groove width of 20 {mu}m and a groove depth of 100 {mu}m on a Nd-doped glass target. The other way is making an array of nanoholes on an alumina target and increasing the laser interaction depth with it. The x-ray fluence enhancement increases as the ionization level of Al becomes higher and the x-ray wavelength becomes shorter. Over 50-fold enhancement was obtained at a soft x-ray wavelength around 6 nm, which corresponds to the emission from Al{sup 8+,9+} ions. (author)

  10. Target surface structure effects on x-ray generation from laser produced plasma

    International Nuclear Information System (INIS)

    Nishikawa, Tadashi; Nakano, Hidetoshi; Uesugi, Naoshi

    2000-01-01

    We demonstrated two different methods to increase the x-ray conversion efficiency of laser-produced plasma by modifying the target surface structure. One way is making a rectangular groove on a target surface and confining a laser-produced plasma in it. By the plasma collision process, a time and wavelength (4-10 nm) integrated soft x-ray fluence enhancement of 35 times was obtained at a groove width of 20 μm and a groove depth of 100 μm on a Nd-doped glass target. The other way is making an array of nanoholes on an alumina target and increasing the laser interaction depth with it. The x-ray fluence enhancement increases as the ionization level of Al becomes higher and the x-ray wavelength becomes shorter. Over 50-fold enhancement was obtained at a soft x-ray wavelength around 6 nm, which corresponds to the emission from Al 8+,9+ ions. (author)

  11. Simulation of a dense plasma focus x-ray source

    International Nuclear Information System (INIS)

    Stark, R.A.

    1994-01-01

    The authors are performing simulations of the magnetohydrodynamics of a Dense Plasma Focus (DPF) x-ray source located at Science Research Laboratory (SRL), Alameda, CA, in order to optimize its performance. The SRL DPF, which was developed as a compact source for x-ray lithography, operates at 20 Hz, giving x-ray power (9--14 Angstroms) of 500 W using neon gas. The simulations are performed with the two dimensional MHD code MACH2, developed by Mission Research Corporation, with a steady state corona model as the equation of state. The results of studies of the sensitivity of x-ray output to charging voltage and current, and to initial gas density will be presented. These studies should indicate ways to optimize x-ray production efficiency. Simulations of various inner electrode configurations will also be presented

  12. Flash X-ray

    International Nuclear Information System (INIS)

    Sato, Eiichi

    2003-01-01

    Generation of quasi-monochromatic X-ray by production of weakly ionized line plasma (flash X-ray), high-speed imaging by the X-ray and high-contrast imaging by the characteristic X-ray absorption are described. The equipment for the X-ray is consisted from the high-voltage power supply and condenser, turbo molecular pump, and plasma X-ray tube. The tube has a long linear anticathode to produce the line plasma and flash X-ray at 20 kA current at maximum. X-ray spectrum is measured by the imaging plate equipped in the computed radiography system after diffracted by a LiF single crystal bender. Cu anticathode generates sharp peaks of K X-ray series. The tissue images are presented for vertebra, rabbit ear and heart, and dog heart by X-ray fluoroscopy with Ce anticathode. Generation of K-orbit characteristic X-ray with extremely low bremsstrahung is to be attempted for medical use. (N.I.)

  13. The Focusing Optics X-ray Solar Imager (FOXSI) SMEX Mission

    Science.gov (United States)

    Christe, S.; Shih, A. Y.; Krucker, S.; Glesener, L.; Saint-Hilaire, P.; Caspi, A.; Allred, J. C.; Battaglia, M.; Chen, B.; Drake, J. F.; Gary, D. E.; Goetz, K.; Gburek, S.; Grefenstette, B.; Hannah, I. G.; Holman, G.; Hudson, H. S.; Inglis, A. R.; Ireland, J.; Ishikawa, S. N.; Klimchuk, J. A.; Kontar, E.; Kowalski, A. F.; Massone, A. M.; Piana, M.; Ramsey, B.; Schwartz, R.; Steslicki, M.; Turin, P.; Ryan, D.; Warmuth, A.; Veronig, A.; Vilmer, N.; White, S. M.; Woods, T. N.

    2017-12-01

    We present FOXSI (Focusing Optics X-ray Solar Imager), a Small Explorer (SMEX) Heliophysics mission that is currently undergoing a Phase A concept study. FOXSI will provide a revolutionary new perspective on energy release and particle acceleration on the Sun. FOXSI is a direct imaging X-ray spectrometer with higher dynamic range and better than 10x the sensitivity of previous instruments. Flown on a 3-axis-stabilized spacecraft in low-Earth orbit, FOXSI uses high-angular-resolution grazing-incidence focusing optics combined with state-of-the-art pixelated solid-state detectors to provide direct imaging of solar hard X-rays for the first time. FOXSI is composed of a pair of x-ray telescopes with a 14-meter focal length enabled by a deployable boom. Making use of a filter-wheel and high-rate-capable solid-state detectors, FOXSI will be able to observe the largest flares without saturation while still maintaining the sensitivity to detect x-ray emission from weak flares, escaping electrons, and hot active regions. This mission concept is made possible by past experience with similar instruments on two FOXSI sounding rocket flights, in 2012 and 2014, and on the HEROES balloon flight in 2013. FOXSI's hard X-ray imager has a field of view of 9 arcminutes and an angular resolution of better than 8 arcsec; it will cover the energy range from 3 up to 50-70 keV with a spectral resolution of better than 1 keV; and it will have sub-second temporal resolution.

  14. Backscatter, anisotropy, and polarization of solar hard X-rays

    International Nuclear Information System (INIS)

    Bai, T.; Ramaty, R.

    1978-01-01

    Hard X-rays incident upon the photosphere with energies > or approx. =15 keV have high probabilities of backscatter due to Compton collisions with electrons. This effect has a strong influence on the spectrum, intensity, and polarization of solar hard X-rays - especially for anisotropic models in which the primary X-rays are emitted predominantly toward the photosphere. We have carried out a detailed study of X-ray backscatter, and we have investigated the interrelated problems of anisotropy, polarization, center-to-limb variation of the X-ray spectrum, and Compton backscatter in a coherent fashion. The results of this study are compared with observational data. Because of the large contribution from backscatter, for an anisotropic primary X-ray source which is due to bremsstrahlung of accelerated electrons moving predominantly down toward the photosphere, the observed X-ray flux around 30 keV does not depend significantly on the position of flare on the Sun. For such an anisotropic source, the X-ray spectrum observed in the 15-50 keV range becomes steeper with the increasing heliocentric angle of the flare. These results are compatible with the data. The degree of polarization of the sum of the primary and reflected X-rays with energies between about 15 and 30 keV can be very large for anisotropic primary X-ray sources, but it is less than about 4% for isotropic sources. We also discuss the characteristics of the brightness distribution of the X-ray albedo patch created by the Compton backscatter. The height and anisotropy of the primary hard X-ray source might be inferred from the study of the albedo patch

  15. The First ALMA Observation of a Solar Plasmoid Ejection from an X-Ray Bright Point

    Energy Technology Data Exchange (ETDEWEB)

    Shimojo, Masumi [National Astronomical Observatory of Japan, Tokyo, 181-8588 (Japan); Hudson, Hugh S. [School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ (United Kingdom); White, Stephen M. [Space Vehicles Directorate, Air Force Research Laboratory, Kirtland AFB, NM 87117-5776 (United States); Bastian, Timothy S. [National Radio Astronomy Observatory, Charlottesville, VA 22903 (United States); Iwai, Kazumasa, E-mail: masumi.shimojo@nao.ac.jp [Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, 464-8601 (Japan)

    2017-05-20

    Eruptive phenomena such as plasmoid ejections or jets are important features of solar activity and have the potential to improve our understanding of the dynamics of the solar atmosphere. Such ejections are often thought to be signatures of the outflows expected in regions of fast magnetic reconnection. The 304 Å EUV line of helium, formed at around 10{sup 5} K, is found to be a reliable tracer of such phenomena, but the determination of physical parameters from such observations is not straightforward. We have observed a plasmoid ejection from an X-ray bright point simultaneously at millimeter wavelengths with ALMA, at EUV wavelengths with SDO /AIA, and in soft X-rays with Hinode /XRT. This paper reports the physical parameters of the plasmoid obtained by combining the radio, EUV, and X-ray data. As a result, we conclude that the plasmoid can consist either of (approximately) isothermal ∼10{sup 5} K plasma that is optically thin at 100 GHz, or a ∼10{sup 4} K core with a hot envelope. The analysis demonstrates the value of the additional temperature and density constraints that ALMA provides, and future science observations with ALMA will be able to match the spatial resolution of space-borne and other high-resolution telescopes.

  16. Bright ultrashort x-rays from intense subpicosecond laser-plasma interactions

    International Nuclear Information System (INIS)

    Umstadter, D.

    1995-01-01

    Short-pulse, high-intensity lasers interacting with solid targets make possible the study of a new class of laser-plasma interactions. They are unique because during the ultrashort laser pulse relatively little expansion occurs, and the density scale length remains much less than the laser wavelength. This makes possible the direct deposition of a significant amount of the laser energy at close to solid density. Steep plasma temperature and density gradients subsequently cause rapid cooling, resulting in highly non-equilibrium conditions and the concurrent emission of extremely bright ultrashort x-ray pulses. In this study, the latter are investigated experimentally with temporally and spectrally resolved soft x-ray diagnostics. The emitted x-ray spectra from solid targets with various atomic numbers are characterized for a laser pulse width τ l ∼ 400 fs. These ultrashort x rays may be used as (1) a diagnostic of solid-density plasma conditions, (2) a tool for the study of radiation hydrodynamics in a parameter regime that is otherwise inaccessible, and (3) a source for time-resolved diffraction, spectroscopy, or microscopy studies of transient chemical, biological or physical phenomena

  17. Plasma spectroscopy diagnostics in pulsed-power X-ray radiography diode research

    International Nuclear Information System (INIS)

    Maron, Yitzhak; Oliver, Bryan Velten; Portillo, Salvador; Johnston, Mark D.; Rose, David Vincent; Hahn, Kelly Denise; Schamiloglu, Edl; Welch, Dale R.; Droemer, Darryl W.; Rovang, Dean Curtis; Maenchen, John Eric

    2005-01-01

    Spectroscopic investigations in the visible and near UV are underway to study plasmas present in X-ray radiography diodes during the time of the electron beam propagation. These studies are being performed on the RITS-3 accelerator (5.25 MV and 120 kA) at Sandia National Laboratories using several diode configurations. The proper characterization of the plasmas occurring during the time of the X-ray pulse can lead to a greater understanding of diode behavior and X-ray spot size evolution. By studying these plasmas along with the use of selective dopants, insights into such phenomena as impedance collapse, thermal and non-thermal species behavior, charge and current neutralization, anode and cathode plasma formation and propagation, and beam/foil interactions, can be obtained. Information from line and continuum emission and absorption can give key plasma parameters such as temperatures, densities, charge states, and expansion velocities. This information is important for proper modeling and future predictive capabilities for the design and improvement of flash X-ray radiography diodes. Diagnostics include a gated, intensified multichannel plate camera combined with a 1 meter Czerny-Turner monochromator with a multi-fiber spectral input, allowing for both temporal and spatial resolution. Recent results are presented.

  18. Quantitative X-ray spectroscopy of sodium Z-pinch plasmas for Na/ne photopumping

    International Nuclear Information System (INIS)

    Burkhalter, P.G.; Mehlman, G.; Apruzese, J.P.; Newman, D.A.; Scherrer, V.E.; Young, F.C.; Stephanakis, S.J.; Hinshelwood, D.D.

    1990-01-01

    Spectra of sodium K-shell x-ray emission were measured for implosions of sodium-bearing plasmas produced on the Naval Research Laboratory Gamble II pulsed-power generator. Sodium fluoride from a capillary discharge provided the initial plasma for these fast Z-pinch implosions. Spatially-resolved images, corresponding to sodium K-shell x-rays from a 3 to 4 cm long plasma column, were recorded with a curved-crystal spectrograph. Non-uniform emission was observed along this column. The diameter of the plasma along the column (1-5 mm) was determined from time-integrated pinhole-camera images, and the duration of the x-ray emission (15-23 ns FWHM) was measured with a vacuum x-ray diode. Absolute emissivities were determined for X-rays from the n=2-1 and n=3-1 transitions in Na X and Na XI. Emissivities calculated using a collisional-radiative equilibrium model were fitted to these measurements to determine plasma temperatures of 230 to 550 eV and electron densities of 0.2 to 4.0 x 10 20 cm -3 at several locations along the plasma column. The slope of the recombination continuum was also used to determine temperatures of 200 to 300 eV and 200 to 400 eV for Na X and Na XI ions, respectively. Absolute intensity measurements of the n=2-1 line emissions from Na X and Na XI, averaged over the entire plasma length, indicated shot-to-shot variations of more than a factor of two in these implosions. (author)

  19. Imaging of exploding wire plasmas by high-luminosity monochromatic X-ray backlighting using an X-pinch radiation source

    Energy Technology Data Exchange (ETDEWEB)

    Pikuz, S A; Shelkovenko, T A; Romanova, V M [Russian Academy of Sciences, Moscow (Russian Federation). P.N. Lebedev Physical Inst.; Hammer, D A [Cornell Univ., Ithaca, NY (United States). Laboratory of Plasma Studies; Faenov, A Ya; Pikuz, T A [VNIIFTRI, Mendeleevo (Russian Federation). Multicharged Ions Spectral Data Center

    1997-12-31

    A new diagnostic method for dense plasmas, monochromatic x-ray backlighting, is described. In this method, shadow images of a bright, dense plasma can be obtained with high spatial resolution using monochromatic radiation from a separate plasma, permitting a major reduction in the required backlighting source power. The object plasma is imaged utilizing spherically bent mica crystals as the x-ray optical elements. Images of test objects obtained using x-ray radiation having different photon energies are presented. Shadow images of exploding Al wire plasmas in the ls{sup 2}-1s3p line radiation of He-like Al XII are also shown. Spatial resolution as fine as 4 {mu}m is demonstrated. The scheme described is useful for backlighting extended high density plasmas, and could be a less costly alternative to using X-ray lasers for such purposes. (author). 7 figs., 10 refs.

  20. XMM-Newton detects X-ray 'solar cycle' in distant star

    Science.gov (United States)

    2004-05-01

    The Sun as observed by SOHO hi-res Size hi-res: 708 Kb The Sun as observed by SOHO The Sun as observed by the ESA/NASA SOHO observatory near the minimum of the solar cycle (left) and near its maximum (right). The signs of solar activity near the maximum are clearly seen. New XMM-Newton observations suggest that this behaviour may be typical of stars like the Sun, such as HD 81809 in the constellation Hydra. Solar flare - 4 November 2003 The huge flare produced on 4 November 2003 This image of the Sun, obtained by the ESA/NASA SOHO observatory, shows the powerful X-ray flare that took place on 4 November 2003. The associated coronal mass ejection, coming out of the Sun at a speed of 8.2 million kilometres per hour, hit the Earth several hours later and caused disruptions to telecommunication and power distribution lines. New XMM-Newton observations suggest that this behaviour may be typical of stars like the Sun, such as HD 81809 in the constellation Hydra. Since the time Galileo discovered sunspots, in 1610, astronomers have measured their number, size and location on the disc of the Sun. Sunspots are relatively cooler areas on the Sun that are observed as dark patches. Their number rises and falls with the level of activity of the Sun in a cycle of about 11 years. When the Sun is very active, large-scale phenomena take place, such as the flares and coronal mass ejections observed by the ESA/NASA solar observatory SOHO. These events release a large amount of energy and charged particles that hit the Earth and can cause powerful magnetic storms, affecting radio communications, power distribution lines and even our weather and climate. During the solar cycle, the X-ray emission from the Sun varies by a large amount (about a factor of 100) and is strongest when the cycle is at its peak and the surface of the Sun is covered by the largest number of spots. ESA's X-ray observatory, XMM-Newton, has now shown for the first time that this cyclic X-ray behaviour is common to

  1. Lower Ionosphere Sensitivity to Solar X-ray Flares Over a Complete Solar Cycle Evaluated From VLF Signal Measurements

    Science.gov (United States)

    Macotela, Edith L.; Raulin, Jean-Pierre; Manninen, Jyrki; Correia, Emília; Turunen, Tauno; Magalhães, Antonio

    2017-12-01

    The daytime lower ionosphere behaves as a solar X-ray flare detector, which can be monitored using very low frequency (VLF) radio waves that propagate inside the Earth-ionosphere waveguide. In this paper, we infer the lower ionosphere sensitivity variation over a complete solar cycle by using the minimum X-ray fluence (FXmin) necessary to produce a disturbance of the quiescent ionospheric conductivity. FXmin is the photon energy flux integrated over the time interval from the start of a solar X-ray flare to the beginning of the ionospheric disturbance recorded as amplitude deviation of the VLF signal. FXmin is computed for ionospheric disturbances that occurred in the time interval of December-January from 2007 to 2016 (solar cycle 24). The computation of FXmin uses the X-ray flux in the wavelength band below 0.2 nm and the amplitude of VLF signals transmitted from France (HWU), Turkey (TBB), and U.S. (NAA), which were recorded in Brazil, Finland, and Peru. The main result of this study is that the long-term variation of FXmin is correlated with the level of solar activity, having FXmin values in the range (1 - 12) × 10-7 J/m2. Our result suggests that FXmin is anticorrelated with the lower ionosphere sensitivity, confirming that the long-term variation of the ionospheric sensitivity is anticorrelated with the level of solar activity. This result is important to identify the minimum X-ray fluence that an external source of ionization must overcome in order to produce a measurable ionospheric disturbance during daytime.

  2. High-intensity X-rays interaction with matter processes in plasmas, clusters, molecules and solids

    CERN Document Server

    Hau-Riege, Stefan P

    2012-01-01

    Filling the need for a book bridging the effect of matter on X-ray radiation and the interaction of x-rays with plasmas, this monograph provides comprehensive coverage of the topic. As such, it presents and explains such powerful new X-ray sources as X-ray free-electron lasers, as well as short pulse interactions with solids, clusters, molecules, and plasmas, and X-ray matter interactions as a diagnostic tool. Equally useful for researchers and practitioners working in the field.

  3. From laser-plasma accelerators to femtosecond X-ray sources: study, development and applications

    International Nuclear Information System (INIS)

    Corde, S.

    2012-01-01

    During the relativistic interaction between a short and intense laser pulse and an underdense plasma, electrons can be injected and accelerated up to hundreds of MeV in an accelerating structure formed in the wake of the pulse: this is the so-called laser-plasma accelerator. One of the major perspectives for laser-plasma accelerators resides in the realization of compact sources of femtosecond x-ray beams. In this thesis, two x-ray sources was studied and developed. The betatron radiation, intrinsic to laser-plasma accelerators, comes from the transverse oscillations of electrons during their acceleration. Its characterization by photon counting revealed an x-ray beam containing 10"9 photons, with energies extending above 10 keV. We also developed an all-optical Compton source producing photons with energies up to hundreds of keV, based on the collision between a photon beam and an electron beam. The potential of these x-ray sources was highlighted by the realization of single shot phase contrast imaging of a biological sample. Then, we showed that the betatron x-ray radiation can be a powerful tool to study the physics of laser-plasma acceleration. We demonstrated the possibility to map the x-ray emission region, which gives a unique insight into the interaction, permitting us for example to locate the region where electrons are injected. The x-ray angular and spectral properties allow us to gain information on the transverse dynamics of electrons during their acceleration. (author)

  4. Common SphinX and RHESSI observations of solar flares

    Science.gov (United States)

    Mrozek, T.; Gburek, S.; Siarkowski, M.; Sylwester, B.; Sylwester, J.; Gryciuk, M.

    The Polish X-ray spectrofotometer SphinX has observed a great number of solar flares in the year 2009 - during the most quiet solar minimum almost over the last 100 years. Hundreds of flares have been recorded due to excellent sensitivity of SphinX's detectors. The Si-PIN diodes are about 100 times more sensitive to X-rays than GOES X-ray Monitors. SphinX detectors were absolutely calibrated on Earth with a use of the BESSY synchrotron. In space observations were made in the range 1.2-15~keV with 480~eV energy resolution. SphinX data overlap with the low-energy end of the Ramaty High Energy Solar Spectroscopic Imager (RHESSI) data. RHESSI detectors are quite old (7 years in 2009), but still sensitive enough to provide us with observations of extremely weak solar flares such as those which occurred in 2009. We have selected a group of flares simultaneously observed by RHESSI and SphinX and performed a spectroscopic analysis of the data. Moreover, we compared the physical parameters of these flares plasma. Preliminary results of the comparison show very good agreement between both instruments.

  5. VizieR Online Data Catalog: WATCH Solar X-Ray Burst Catalogue (Crosby+ 1998)

    Science.gov (United States)

    Crosby, N.; Lund, N.; Vilmer, N.; Sunyaev, R.

    1998-01-01

    Catalogue containing solar X-ray bursts measured by the Danish Wide Angle Telescope for Cosmic Hard X-Rays (WATCH) experiment aboard the Russian satellite GRANAT in the deca-keV energy range. Table 1 lists the periods during which solar observations with WATCH are available (WATCH ON-TIME) and where the bursts listed in the catalogue have been observed. (2 data files).

  6. New Observations of Soft X-ray (0.5-5 keV) Solar Spectra

    Science.gov (United States)

    Caspi, A.; Woods, T. N.; Mason, J. P.; Jones, A. R.; Warren, H. P.

    2013-12-01

    The solar corona is the brightest source of X-rays in the solar system, and the X-ray emission is highly variable on many time scales. However, the actual solar soft X-ray (SXR) (0.5-5 keV) spectrum is not well known, particularly during solar quiet periods, as, with few exceptions, this energy range has not been systematically studied in many years. Previous observations include high-resolution but very narrow-band spectra from crystal spectrometers (e.g., Yohkoh/BCS), or integrated broadband irradiances from photometers (e.g., GOES/XRS, TIMED/XPS, etc.) that lack detailed spectral information. In recent years, broadband measurements with moderate energy resolution (~0.5-0.7 keV FWHM) were made by SphinX on CORONAS-Photon and SAX on MESSENGER, although they did not extend to energies below ~1 keV. We present observations of solar SXR emission obtained using new instrumentation flown on recent SDO/EVE calibration rocket underflights. The photon-counting spectrometer, a commercial Amptek X123 with a silicon drift detector and an 8 μm Be window, measures the solar disk-integrated SXR emission from ~0.5 to >10 keV with ~0.15 keV FWHM resolution and 1 s cadence. A novel imager, a pinhole X-ray camera using a cooled frame-transfer CCD (15 μm pixel pitch), Ti/Al/C filter, and 5000 line/mm Au transmission grating, images the full Sun in multiple spectral orders from ~0.1 to ~5 nm with ~10 arcsec/pixel and ~0.01 nm/pixel spatial and spectral detector scales, respectively, and 10 s cadence. These instruments are prototypes for future CubeSat missions currently being developed. We present new results of solar observations on 04 October 2013 (NASA sounding rocket 36.290). We compare with previous results from 23 June 2012 (NASA sounding rocket 36.286), during which solar activity was low and no signal was observed above ~4 keV. We compare our spectral and imaging measurements with spectra and broadband irradiances from other instruments, including SDO/EVE, GOES/XRS, TIMED

  7. Optimising hard X-ray generation from laser-produced plasmas

    International Nuclear Information System (INIS)

    Lindheimer, C.

    1995-04-01

    The aim of this work is to increase the X-ray yield for a laser produced plasma by optimising the focusing conditions and temporal shape of the laser pulses. The focusing conditions are improved by introducing a control system that secures the laser target surface to exact focus within a range of a few micrometers, allowing continuously high laser intensity for plasma generation. The temporal shape of the laser pulses is changed by introducing a saturable absorber in the laser beam. The laser produces a substantial pre-pulse that heats and expands the target material prior to main pulse arrival. The saturable absorber can increase the main pulse/pre-pulse ratio of the laser pulse up to four orders of magnitude and consequently reduce expansion of the target material before the main pulse. The belief is that an increase in target density at the time of main pulse arrival will change the energy distribution of the X-rays, towards a more efficient X-ray production in the hard X-ray region. This report and the work connected to it, includes the preliminary measurements and results for these improvements. 17 refs

  8. FIRST IMAGES FROM THE FOCUSING OPTICS X-RAY SOLAR IMAGER

    Energy Technology Data Exchange (ETDEWEB)

    Krucker, Säm; Glesener, Lindsay; Turin, Paul; McBride, Stephen; Glaser, David; Fermin, Jose; Lin, Robert [Space Sciences Laboratory, University of California at Berkeley, Berkeley, CA (United States); Christe, Steven [NASA Goddard Space Flight Center, Greenbelt, MD (United States); Ishikawa, Shin-nosuke [National Astronomical Observatory, Mitaka (Japan); Ramsey, Brian; Gubarev, Mikhail; Kilaru, Kiranmayee [NASA Marshall Space Flight Center, Huntsville, AL (United States); Takahashi, Tadayuki; Watanabe, Shin; Saito, Shinya [Institute of Space and Astronautical Science (ISAS)/JAXA, Sagamihara (Japan); Tajima, Hiroyasu [Solar-Terrestial Environment Laboratory, Nagoya University, Nagoya (Japan); Tanaka, Takaaki [Department of Physics, Kyoto University, Kyoto (Japan); White, Stephen [Air Force Research Laboratory, Albuquerque, NM (United States)

    2014-10-01

    The Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket payload flew for the first time on 2012 November 2, producing the first focused images of the Sun above 5 keV. To enable hard X-ray (HXR) imaging spectroscopy via direct focusing, FOXSI makes use of grazing-incidence replicated optics combined with fine-pitch solid-state detectors. On its first flight, FOXSI observed several targets that included active regions, the quiet Sun, and a GOES-class B2.7 microflare. This Letter provides an introduction to the FOXSI instrument and presents its first solar image. These data demonstrate the superiority in sensitivity and dynamic range that is achievable with a direct HXR imager with respect to previous, indirect imaging methods, and illustrate the technological readiness for a spaceborne mission to observe HXRs from solar flares via direct focusing optics.

  9. FARIMA MODELING OF SOLAR FLARE ACTIVITY FROM EMPIRICAL TIME SERIES OF SOFT X-RAY SOLAR EMISSION

    International Nuclear Information System (INIS)

    Stanislavsky, A. A.; Burnecki, K.; Magdziarz, M.; Weron, A.; Weron, K.

    2009-01-01

    A time series of soft X-ray emission observed by the Geostationary Operational Environment Satellites from 1974 to 2007 is analyzed. We show that in the solar-maximum periods the energy distribution of soft X-ray solar flares for C, M, and X classes is well described by a fractional autoregressive integrated moving average model with Pareto noise. The model incorporates two effects detected in our empirical studies. One effect is a long-term dependence (long-term memory), and another corresponds to heavy-tailed distributions. The parameters of the model: self-similarity exponent H, tail index α, and memory parameter d are statistically stable enough during the periods 1977-1981, 1988-1992, 1999-2003. However, when the solar activity tends to minimum, the parameters vary. We discuss the possible causes of this evolution and suggest a statistically justified model for predicting the solar flare activity.

  10. Characteristics of x-ray radiation from a gas-puff z-pinch plasma

    International Nuclear Information System (INIS)

    Akiyama, N.; Takasugi, K.

    2002-01-01

    Characteristics of x-ray radiation from Ar gas-puff z-pinch plasma have been investigated by changing delay time of discharge from gas puffing. Intense cloud structure of x-ray image was observed at small delay time region, but the total x-ray signal was not so intense. The x-ray signal increased with increasing the delay time, and hot spots of x-ray image also became intense. Electron temperature was evaluated from x-ray spectroscopic data, and no significant difference in temperature was observed. (author)

  11. Calibration of the hard x-ray detectors for the FOXSI solar sounding rocket

    Science.gov (United States)

    Athiray, P. S.; Buitrago-Casas, Juan Camilo; Bergstedt, Kendra; Vievering, Juliana; Musset, Sophie; Ishikawa, Shin-nosuke; Glesener, Lindsay; Takahashi, Tadayuki; Watanabe, Shin; Courtade, Sasha; Christe, Steven; Krucker, Säm.; Goetz, Keith; Monson, Steven

    2017-08-01

    The Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket experiment conducts direct imaging and spectral observation of the Sun in hard X-rays, in the energy range 4 to 20 keV. These high-sensitivity observations are used to study particle acceleration and coronal heating. FOXSI is designed with seven grazing incidence optics modules that focus X-rays onto seven focal plane detectors kept at a 2m distance. FOXSI-1 was flown with seven Double-sided Si Strip Detectors (DSSD), and two of them were replaced with CdTe detectors for FOXSI-2. The upcoming FOXSI-3 flight will carry DSSD and CdTe detectors with upgraded optics for enhanced sensitivity. The detectors are calibrated using various radioactive sources. The detector's spectral response matrix was constructed with diagonal elements using a Gaussian approximation with a spread (sigma) that accounts for the energy resolution of the detector. Spectroscopic studies of past FOXSI flight data suggest that the inclusion of lower energy X-rays could better constrain the spectral modeling to yield a more precise temperature estimation of the hot plasma. This motivates us to carry out an improved calibration to better understand the finer-order effects on the spectral response, especially at lower energies. Here we report our improved calibration of FOXSI detectors using experiments and Monte-Carlo simulations.

  12. Periodicities in the X-ray Emission from the Solar Corona: SphinX and SOXS Observations

    Science.gov (United States)

    Steślicki, M.; Awasthi, A. K.; Gryciuk, M.; Jain, R.

    The structure and evolution of the solar magnetic field is driven by a magnetohydrodynamic dynamo operating in the solar interior, which induces various solar activities that exhibit periodic variations on different timescales. Therefore, probing the periodic nature of emission originating from the solar corona may provide insights of the convection-zone-photosphere-corona coupling processes. We present the study of the mid-range periodicities, between rotation period (˜27 days) and the Schwabe cycle period (˜11 yr), in the solar soft X-ray emission, based on the data obtained by two instruments: SphinX and SOXS in various energy bands.

  13. The First ALMA Observation of a Solar Plasmoid Ejection from an X-Ray Bright Point

    Science.gov (United States)

    Shimojo, M.; Hudson, H. S.; White, S. M.; Bastian, T.; Iwai, K.

    2017-12-01

    Eruptive phenomena are important features of energy releases events, such solar flares, and have the potential to improve our understanding of the dynamics of the solar atmosphere. The 304 A EUV line of helium, formed at around 10^5 K, is found to be a reliable tracer of such phenomena, but the determination of physical parameters from such observations is not straightforward. We have observed a plasmoid ejection from an X-ray bright point simultaneously with ALMA, SDO/AIA, and Hinode/XRT. This paper reports the physical parameters of the plasmoid obtained by combining the radio, EUV, and X-ray data. As a result, we conclude that the plasmoid can consist either of (approximately) isothermal ˜10^5 K plasma that is optically thin at 100 GHz, or a ˜10^4 K core with a hot envelope. The analysis demonstrates the value of the additional temperature and density constraints that ALMA provides, and future science observations with ALMA will be able to match the spatial resolution of space-borne and other high-resolution telescopes.

  14. The X-ray footprint of the circumnuclear disc

    Science.gov (United States)

    Mossoux, Enmanuelle; Eckart, Andreas

    2018-03-01

    We studied the central regions of the Galactic Centre to determine if the circumnuclear disc (CND) acts as an absorber or a barrier for the central X-rays diffuse emission. After reprocessing 4.6 Ms of Chandra observations, we were able to detect, for the first time, a depression in the X-ray luminosity of the diffuse emission whose size and location correspond to those of the CND. We extracted the X-ray spectra for various regions inside the CND footprint as well as for the region where the footprint is observed and for a region located outside the footprint. We simultaneously fitted these spectra as an optically thin plasma whose absorption by the interstellar medium (ISM) and by the local plasma were fitted independently using the Markov chain Monte Carlo method. The hydrogen column density of the ISM is 7.5 × 1022 cm-2. The X-ray diffuse emission inside the CND footprint is formed by a 2T plasma of 1 and 4 keV with slightly super-solar abundances except for the iron and carbon that are sub-solar. The plasma from the CND, in turn, is better described by a 1T model with abundances and local hydrogen column density that are very different from those of the innermost regions. The large iron abundance in this region confirms that the CND is dominated by the shock-heated ejecta of the Sgr A East supernova remnant. We deduced that the CND rather acts as a barrier for the Galactic Centre plasma and that the plasma located outside the CND may correspond to the collimated outflow possibly created by Sgr A* or the interaction between the wind of massive stars and the mini-spiral material.

  15. X-ray lasing in colliding plasmas

    International Nuclear Information System (INIS)

    Clark, R.W.; Davis, J.; Velikovich, A.L.; Whitney, K.G.

    1997-01-01

    Conditions favorable for the achievement of population inversion and large gains in short-pulse laser-heated selenium have been reported on previously [K. G. Whitney et al., Phys. Rev. E 50, 468 (1994)]. However, the required density profiles to minimize refraction and amplification losses can be difficult to achieve in conventional laser heated blowoff plasmas. The feasibility of accelerating plasma with a laser, and letting it collide with a solid density wall plasma has been explored. The density of the resulting shocked plasma can be controlled and refraction can be reduced in this design. A radiation hydrodynamics model is used to simulate the collision of the laser produced selenium plasma with the wall plasma. The heating of the stagnated plasma with a short-pulse laser is then simulated, providing the hydrodynamic response of the selenium plasma and detailed configuration nonequilibrium atomic populations. From the results of these calculations, it appears feasible to create an x-ray lasing selenium plasma with gains in the J=0 endash 1 line at 182 Angstrom in excess of 100cm -1 . copyright 1997 American Institute of Physics

  16. X-ray spectroscopic characterization of shock-ignition-relevant plasmas

    Czech Academy of Sciences Publication Activity Database

    Šmíd, Michal; Antonelli, L.; Renner, Oldřich

    2013-01-01

    Roč. 53, č. 2 (2013), 233-236 ISSN 1210-2709 R&D Projects: GA ČR GAP205/10/0814 Institutional support: RVO:68378271 Keywords : hot electrons * shock ignition * laser-produced plasma * X-ray spectroscopy * Kα radiation Subject RIV: BL - Plasma and Gas Discharge Physics

  17. Plasma Heating in Solar Microflares: Statistics and Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kirichenko, A. S.; Bogachev, S. A. [Lebedev Physical Institute of the Russian Academy of Sciences, Moscow, 119991 (Russian Federation)

    2017-05-01

    In this paper we present the results of an analysis of 481 weak solar flares, from A0.01 class flares to the B GOES class, that were observed during the period of extremely low solar activity from 2009 April to July. For all flares we measured the temperature of the plasma in the isothermal and two-temperature approximations and tried to fit its relationship with the X-ray class using exponential and power-law functions. We found that the whole temperature distribution in the range from A0.01 to X-class cannot be fit by one exponential function. The fitting for weak flares below A1.0 is significantly steeper than that for medium and large flares. The power-law approximation seems to be more reliable: the corresponding functions were found to be in good agreement with experimental data both for microflares and for normal flares. Our study predicts that evidence of plasma heating can be found in flares starting from the A0.0002 X-ray class. Weaker events presumably cannot heat the surrounding plasma. We also estimated emission measures for all flares studied and the thermal energy for 113 events.

  18. Analysis of OGO-5 and OSO-7 x-ray data. Final report

    International Nuclear Information System (INIS)

    Moore, R.L.

    1975-02-01

    The physical nature of solar flares implied by the data was studied. The empirical results were obtained primarily from the OGO-5 and OSO-7 x-ray data in combination with optical data. The principal conclusions regarding the physics of flares are the following. (1) Flares are produced by magnetic field reconnection. (2) The resulting thermal x-ray plasma is cooled primarily by heat conduction rather than by radiative cooling. (3) The heating and cooling of the thermal x-ray plasma are approximately in balance during the maximum phase of the flare. (auth)

  19. Analyais of solar X-ray emission line profiles

    International Nuclear Information System (INIS)

    Burek, A.J.; Marrus, D.M.; Blake, R.L.; Fenimore, E.E.

    1981-01-01

    We report results of the analysis of the X-ray emission line profiles for the Ne X La and Fe XVII 4d 1 P 1 lines produced in an active region that was undergoing a radio and X-ray gradual rise and fall (GRF) in intensity. The spectra were obtained with collimated Bragg spectrometers launched on a rocket from White Sands Missile Range on 1976 March 26. Using a crystal of ammonium acid phthalate, we have fully resolved the Ne X La and Fe XVII 4d 1 P 1 lines, permitting an accurate determinination of the Ne X La intensity and allowing Doppler broadened profiles for lines formed from ions having greatly different atomic mass and charge to be measured. An isothermal model derived from the Ne IX/Ne X resonance line intensity ratio gives an electron temperature of 3.4 x 10 6 K. An isothermal model, however, fails to account for the intensities of all lines and continuum observed. All multitemperature models that do reproduce the observed relative line intensities require the presence of a hot plasma component with an electron temperature in excess of 5 x 10 6 K. The presence of a high temperature component is also suggested by the measured line to continuum ratio of 3.6 in the 12--15 A wavelength interval. Interpretation of the line profiles in terms of a multitemperature model requires an rms turbulence velocity of 48 +- 15 km s -1 for Fe XVII 1 P 1 and 74 +- 54 km s - 2exclamation for Ne X La at the 95% confidence level. Collimated scans across the active region show the presence of a compact source of intense X-ray emission close to the magnetic neutral line, which is very probably the GRF plasma

  20. Measurement of soft X-ray power from high-power Z-pinch plasma

    International Nuclear Information System (INIS)

    Wang Wensheng; Qiu Aici; Sun Fengrong; Luo Jianhui; Zhou Haisheng; He Duohui

    2003-01-01

    A Ni-film bolometer driven by the pulsed constant-voltage supply was developed for measuring soft X-ray energy under 1 keV generated from the Qiang-Guang-I, while the measuring system of the soft X-ray power was established with an X-ray diode detector. Results of the soft X-ray energy and power measurements were obtained at the experiment of Kr gas-puff high-power Z-pinch plasma

  1. Solar X-ray Spectrometer (SOXS) Mission – Low Energy Payload

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... We present the first results from the 'Low Energy Detector' payload of 'Solar X-ray Spectrometer (SOXS)' mission, which was launched onboard GSAT-2 Indian spacecraft on 08 May 2003 by GSLV-D2 rocket to study the solar flares. The SOXS Low Energy Detector (SLD) payload was designed, developed ...

  2. He-like spectra from laboratory plasmas and solar flares

    International Nuclear Information System (INIS)

    Kato, Takako

    1990-01-01

    The X-ray spectra of He-like ions from tokamaks and solar flares have been measured. Several physical parameters of plasma can be derived from the X-ray spectra of He-like ions. The ion temperature can be derived from the doppler width of a resonance line. The electron temperature is obtained from the intensity ratio of dielectronic satellite lines to a resonance line. The energy level for the prominent lines is shown. The line q is produced mainly by the inner-shell excitation of Li-like ions, and line beta is produced by the inner-shell excitation of Be-like ions. The intensity ratios give the ion density ratios. The intensities of the intercombination and the forbidden lines are affected by the recombination from H-like ions. The synthetic spectra including excitation, ionization and recombination processes are fitted to the measurement. In this paper, the He-like X-ray spectra of the titanium ions from TFTR tokamak plasma and of the iron ions from solar flares are discussed, paying attention to the presence of high energy electrons which affect the spectra and ionization balance. Atomic data, the spectra from the TFTR tokamak, the spectra from solar flares and so on are described. (K.I.)

  3. X-ray Spectroscopic Characterization of Shock-Ignition-Relevant plasmas

    Directory of Open Access Journals (Sweden)

    Michal Šmíd

    2013-01-01

    Full Text Available Experiments with multilayer plastic/Cu targets performed at a PALS laser system aimed at the study of matter at conditions relevant to a shock ignition ICF scheme, and, in particular, at the investigation of hot electrons generation. Plasma temperature and density were obtained using high-resolution X-ray spectroscopy. 2D-spatially resolved quasi–monochromatic imaging was observing the hot electrons via fluorescence K emission in the copper tracer layer. Found values of plasma temperature 690 ± 10 eV, electron density 3 × 1022 cm-3 and the effective energy of hot electrons 45 ± 20 keV demonstrate the potential of X-ray methods in the characterization of the shock ignition environmental conditions.

  4. Wide Field-of-View Soft X-Ray Imaging for Solar Wind-Magnetosphere Interactions

    Science.gov (United States)

    Walsh, B. M.; Collier, M. R.; Kuntz, K. D.; Porter, F. S.; Sibeck, D. G.; Snowden, S. L.; Carter, J. A.; Collado-Vega, Y.; Connor, H. K.; Cravens, T. E.; hide

    2016-01-01

    Soft X-ray imagers can be used to study the mesoscale and macroscale density structures that occur whenever and wherever the solar wind encounters neutral atoms at comets, the Moon, and both magnetized and unmagnetized planets. Charge exchange between high charge state solar wind ions and exospheric neutrals results in the isotropic emission of soft X-ray photons with energies from 0.1 to 2.0 keV. At Earth, this process occurs primarily within the magnetosheath and cusps. Through providing a global view, wide field-of-view imaging can determine the significance of the various proposed solar wind-magnetosphere interaction mechanisms by evaluating their global extent and occurrence patterns. A summary of wide field-of-view (several to tens of degrees) soft X-ray imaging is provided including slumped micropore microchannel reflectors, simulated images, and recent flight results.

  5. Hard X-Ray Emission from Partially Occulted Solar Flares: RHESSI Observations in Two Solar Cycles

    Energy Technology Data Exchange (ETDEWEB)

    Effenberger, Frederic; Costa, Fatima Rubio da; Petrosian, Vahé [Department of Physics and KIPAC, Stanford University, Stanford, CA 94305 (United States); Oka, Mitsuo; Saint-Hilaire, Pascal; Krucker, Säm [Space Sciences Laboratory, University of California, Berkeley, CA 94720-7450 (United States); Liu, Wei [Bay Area Environmental Research Institute, 625 2nd Street, Suite 209, Petaluma, CA 94952 (United States); Glesener, Lindsay, E-mail: feffen@stanford.edu, E-mail: frubio@stanford.edu [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States)

    2017-02-01

    Flares close to the solar limb, where the footpoints are occulted, can reveal the spectrum and structure of the coronal looptop source in X-rays. We aim at studying the properties of the corresponding energetic electrons near their acceleration site, without footpoint contamination. To this end, a statistical study of partially occulted flares observed with Reuven Ramaty High-Energy Solar Spectroscopic Imager is presented here, covering a large part of solar cycles 23 and 24. We perform detailed spectra, imaging, and light curve analyses for 116 flares and include contextual observations from SDO and STEREO when available, providing further insights into flare emission that were previously not accessible. We find that most spectra are fitted well with a thermal component plus a broken power-law, non-thermal component. A thin-target kappa distribution model gives satisfactory fits after the addition of a thermal component. X-ray imaging reveals small spatial separation between the thermal and non-thermal components, except for a few flares with a richer coronal source structure. A comprehensive light curve analysis shows a very good correlation between the derivative of the soft X-ray flux (from GOES ) and the hard X-rays for a substantial number of flares, indicative of the Neupert effect. The results confirm that non-thermal particles are accelerated in the corona and estimated timescales support the validity of a thin-target scenario with similar magnitudes of thermal and non-thermal energy fluxes.

  6. Solar X-Ray Processes

    Science.gov (United States)

    Mallik, P. C. V.; Brown, J. C.; MacKinnon, A. L.

    Past analyses of solar flares have ignored nonthermal recombination (NTR) emission as a means of producing Hard X-rays (HXRs) in the corona and chromosphere. However, Brown and Mallik (2008, A&A, 481, 507) have shown that NTR can be significant and even exceed nonthermal bremsstrahlung (NTB) emission for certain flare conditions that are quite common. For hot enough plasma (T > 10 MK), HXR emission of a few deka-keV has a large contribution from NTR onto highly ionized heavy elements, especially Fe. Consequently, including NTR has implications for the magnitude and the form of the inferred electron spectrum, F(E), and hence for fast-electron density and energy budgets and for the acceleration mechanisms. We show under what circumstances NTR dominates in deka-keV HXR emission. It is important to note that at high temperatures, HXR emission from thermal electrons (recombination and bremsstrahlung) becomes important. However, NTR dominates over NTB without being swamped by thermal emission in the photon energy (ɛ) regime of 20-30 keV and temperature range of 10-25MK (Fig. 1, left). By integrating the flux for all ɛ > 20keV, i.e., looking at the source luminosity function above 20 keV, we were able to show that by including NTR, the acceleration requirements are less demanding for every event, but to varying degrees based on temperature (T), spectral index (δ) and electron low-energy cut-off (Ec). Our key result is that, for T > 10MK and δ ≈ 5, including NTR reduces the demand for nonthermal electrons by up to 85%. Our paper with these results will be submitted to ApJ Letters.

  7. Diagnosing high density, fast-evolving plasmas using x-ray lasers

    International Nuclear Information System (INIS)

    Cauble, R.; Da Silva, L.B.; Barbee, T.W. Jr.

    1994-09-01

    As x-ray laser (XRL) research has matured, it has become possible to reliably utilize XRLs for applications in the laboratory. Laser coherence, high brightness and short pulse duration all make the XRL a unique tool for the diagnosis of laboratory plasmas. The high brightness of XRLs makes them well-suited for imaging and for interferometry when used in conjunction with multilayer mirrors and beamsplitters. We have utilized a soft x-ray laser in such an imaging system to examine laser-produced plasmas using radiography, moire deflectometry, and interferometry. Radiography experiments yield 100-200 ps snapshots of laser driven foils at a resolution of 1-2 μm. Moire deflectometry with an XRL has been used to probe plasmas at higher density than by optical means. Interferograms, which allow direct measurement of electron density in laser plasmas, have been obtained with this system

  8. CORRELATION OF HARD X-RAY AND WHITE LIGHT EMISSION IN SOLAR FLARES

    Energy Technology Data Exchange (ETDEWEB)

    Kuhar, Matej; Krucker, Säm; Battaglia, Marina; Kleint, Lucia; Casadei, Diego [University of Applied Sciences and Arts Northwestern Switzerland, Bahnhofstrasse 6, 5210 Windisch (Switzerland); Oliveros, Juan Carlos Martinez; Hudson, Hugh S. [Space Sciences Laboratory, University of California, Berkeley, CA 94720-7450 (United States)

    2016-01-01

    A statistical study of the correlation between hard X-ray and white light emission in solar flares is performed in order to search for a link between flare-accelerated electrons and white light formation. We analyze 43 flares spanning GOES classes M and X using observations from the Reuven Ramaty High Energy Solar Spectroscopic Imager and Helioseismic and Magnetic Imager. We calculate X-ray fluxes at 30 keV and white light fluxes at 6173 Å summed over the hard X-ray flare ribbons with an integration time of 45 s around the peak hard-X ray time. We find a good correlation between hard X-ray fluxes and excess white light fluxes, with a highest correlation coefficient of 0.68 for photons with energy of 30 keV. Assuming the thick target model, a similar correlation is found between the deposited power by flare-accelerated electrons and the white light fluxes. The correlation coefficient is found to be largest for energy deposition by electrons above ∼50 keV. At higher electron energies the correlation decreases gradually while a rapid decrease is seen if the energy provided by low-energy electrons is added. This suggests that flare-accelerated electrons of energy ∼50 keV are the main source for white light production.

  9. X-ray calibration facility for plasma diagnostics of the MegaJoule laser

    International Nuclear Information System (INIS)

    Hubert, S.; Prevot, V.

    2013-01-01

    The Laser MegaJoule (LMJ) located at CEA-CESTA will be equipped with x-ray plasma diagnostics using different kinds of x-ray components such as filters, mirrors, crystals, detectors and cameras. To guarantee LMJ measurements, detectors such as x-ray cameras need to be regularly calibrated. An x-ray laboratory is devoted to this task and performs absolute x-ray calibrations for similar x-ray cameras running on Laser Integration Line (LIL). This paper presents the x-ray calibration bench with its x-ray tube based High Energy x-ray Source (HEXS) and some calibration results. By mean of an ingenious transposition system under vacuum absolute x-ray calibration of x-ray cameras, like streak and stripline ones, can be carried out. Coupled to a new collimation system with micrometric accuracy on aperture sensitivity quantum efficiency measurements can be achieved with reduced uncertainties. (authors)

  10. Progress in the applicability of plasma X-ray lasers

    Energy Technology Data Exchange (ETDEWEB)

    Kuehl, T., E-mail: T.Kuehl@gsi.de; Aurand, B.; Bagnoud, V.; Ecker, B.; Eisenbarth, U. [GSI (Germany); Guilbaud, O. [Universite Paris Sud (France); Fils, J.; Goette, S. [GSI (Germany); Habib, J. [Universite Paris Sud (France); Hochhaus, D.; Javorkova, D. [GSI (Germany); Neumayer, P. [Extreme Matter Institute, EMMI (Germany); Kazamias, S.; Pittman, M.; Ros, D. [Universite Paris Sud (France); Seres, J.; Spielmann, Ch. [Friedrich Schiller-University (Germany); Zielbauer, B.; Zimmer, D. [GSI (Germany)

    2010-02-15

    Proposed as satellite-based weapons during the 1980s, X-ray lasing was for a long time only achieved with enormous amounts of pump energy in either nuclear explosions or at kilojoule-class laser installations. During the last few years a tremendous development was achieved, most visible in the realisation of the FEL lasers at DESY and SLAC. As important for a wider applicability is the enormous reduction in pump energy for laser pumped plasma X-ray lasers, which now brings such devices into the range of applications for diagnostics and spectroscopy even in smaller laboratories. Main developments were the transient excitation scheme and the optimized pumping concepts. This paper concentrates on developments at the GSI Helmholtzcenter at Darmstadt aiming towards reliable X-ray laser sources in the range from 50 to several 100 eV. The main driving forces for the laser development at GSI are the possible application for the spectroscopy of Li-like ions in the storage ring ESR and the future storage ring NESR at FAIR, and the interest in novel plasma diagnostics.

  11. Progress in the applicability of plasma X-ray lasers

    International Nuclear Information System (INIS)

    Kuehl, T.; Aurand, B.; Bagnoud, V.; Ecker, B.; Eisenbarth, U.; Guilbaud, O.; Fils, J.; Goette, S.; Habib, J.; Hochhaus, D.; Javorkova, D.; Neumayer, P.; Kazamias, S.; Pittman, M.; Ros, D.; Seres, J.; Spielmann, Ch.; Zielbauer, B.; Zimmer, D.

    2010-01-01

    Proposed as satellite-based weapons during the 1980s, X-ray lasing was for a long time only achieved with enormous amounts of pump energy in either nuclear explosions or at kilojoule-class laser installations. During the last few years a tremendous development was achieved, most visible in the realisation of the FEL lasers at DESY and SLAC. As important for a wider applicability is the enormous reduction in pump energy for laser pumped plasma X-ray lasers, which now brings such devices into the range of applications for diagnostics and spectroscopy even in smaller laboratories. Main developments were the transient excitation scheme and the optimized pumping concepts. This paper concentrates on developments at the GSI Helmholtzcenter at Darmstadt aiming towards reliable X-ray laser sources in the range from 50 to several 100 eV. The main driving forces for the laser development at GSI are the possible application for the spectroscopy of Li-like ions in the storage ring ESR and the future storage ring NESR at FAIR, and the interest in novel plasma diagnostics.

  12. X-ray astronomy

    International Nuclear Information System (INIS)

    Culhane, J.L.; Sanford, P.W.

    1981-01-01

    X-ray astronomy has been established as a powerful means of observing matter in its most extreme form. The energy liberated by sources discovered in our Galaxy has confirmed that collapsed stars of great density, and with intense gravitational fields, can be studied by making observations in the X-ray part of the electromagnetic spectrum. The astronomical objects which emit detectable X-rays include our own Sun and extend to quasars at the edge of the Universe. This book describes the history, techniques and results obtained in the first twenty-five years of exploration. Space rockets and satellites are essential for carrying the instruments above the Earth's atmosphere where it becomes possible to view the X-rays from stars and nebulae. The subject is covered in chapters, entitled: the birth of X-ray astronomy; the nature of X-radiation; X-rays from the Sun; solar-flare X-rays; X-rays from beyond the solar system; supernovae and their remnants; X-rays from binary stars; white dwarfs and neutron stars; black holes; X-rays from galaxies and quasars; clusters of galaxies; the observatories of the future. (author)

  13. X-ray astronomy

    International Nuclear Information System (INIS)

    Giacconi, R.; Gursky, H.

    1974-01-01

    This text contains ten chapters and three appendices. Following an introduction, chapters two through five deal with observational techniques, mechanisms for the production of x rays in a cosmic setting, the x-ray sky and solar x-ray emission. Chapters six through ten include compact x-ray sources, supernova remnants, the interstellar medium, extragalactic x-ray sources and the cosmic x-ray background. Interactions of x rays with matter, units and conversion factors and a catalog of x-ray sources comprise the three appendices. (U.S.)

  14. Bright X-ray source from a laser-driven micro-plasma-waveguide

    CERN Document Server

    Yi, Longqing

    2016-01-01

    Bright tunable x-ray sources have a number of applications in basic science, medicine and industry. The most powerful sources are synchrotrons, where relativistic electrons are circling in giant storage rings. In parallel, compact laser-plasma x-ray sources are being developed. Owing to the rapid progress in laser technology, very high-contrast femtosecond laser pulses of relativistic intensities become available. These pulses allow for interaction with micro-structured solid-density plasma without destroying the structure by parasitic pre-pulses. The high-contrast laser pulses as well as the manufacturing of materials at micro- and nano-scales open a new realm of possibilities for laser interaction with photonic materials at the relativistic intensities. Here we demonstrate, via numerical simulations, that when coupling with a readily available 1.8 Joule laser, a micro-plasma-waveguide (MPW) may serve as a novel compact x-ray source. Electrons are extracted from the walls by the laser field and form a dense ...

  15. Very high resolution UV and X-ray spectroscopy and imagery of solar active regions

    Science.gov (United States)

    Bruner, M.; Brown, W. A.; Haisch, B. M.

    1987-01-01

    A scientific investigation of the physics of the solar atmosphere, which uses the techniques of high resolution soft X-ray spectroscopy and high resolution UV imagery, is described. The experiments were conducted during a series of three sounding rocket flights. All three flights yielded excellent images in the UV range, showing unprecedented spatial resolution. The second flight recorded the X-ray spectrum of a solar flare, and the third that of an active region. A normal incidence multi-layer mirror was used during the third flight to make the first astronomical X-ray observations using this new technique.

  16. Evolution of plasma characteristics for weak X-ray brightenings seen by SphinX during recent deep minimum of solar activity

    Science.gov (United States)

    Sylwester, Barbara; Sylwester, Janusz; Siarkowski, Marek; Gburek, Szymon; Phillips, Kenneth

    Very high sensitivity of SphinX soft X-ray spectrophotometer aboard Coronas-Photon allows to observe spectra of small X-ray brightenings(microflares), many of them with maximum intensities well below the GOES or RHESSI sensitivity thresholds. Hundreds of such small flare-like events have been observed in the period between March and November 2009 with energy resolution better than 0.5 keV. The spectra have been measured in the energy range extending above 1 keV. In this study we investigate the time variability of basic plasma parameters: temperature T and emission measure EM for a number of these weak flare-like events and discuss respective evolutionary patterns on the EM-T diagnostic diagrams. For some of these events, unusual behavior is observed, different from this characteristic for a "normal" flares of higher maximum intensities. Physical scenarios providing possible explanation of such unusual evolutionary patterns will be discussed.

  17. Recurrent pulse trains in the solar hard X-ray flare of 1980 June 7

    International Nuclear Information System (INIS)

    Kiplinger, A.L.; Dennis, B.R.; Frost, K.J.; Orwig, L.E.

    1983-01-01

    This study presents a detailed examination of the solar hard X-ray and γ-ray flare of 1980 June 7 as seen by the Hard X-Ray Burst Spectrometer on SMM. The hard X-ray profile is most unusual in that it is characterized by an initial pulse train of seven intense hard X-ray spikes. However, the event is unique among the 6300 events observed by HXRBS in that the temporal signature of this pulse train recurs twice during the flare. Such signatures of temporal stability in impulsive solar flares have not been observed before. Examinations of the hard X-ray data in conjunction with radio and γ-ray observations show that the 28--480 keV X-ray emission is simultaneous with the 17 GHz microwave fluxes within 128 ms and that the 3.5--6.5 MeV prompt γ-ray line emission is coincident with secondary maxima of the microwave and X-ray fluxes. Studies of the temporal and spectral properties of the pulses indicate that the pulses are not produced by purely reversible processes, and that if the source is oscillatory, it is not a high quality oscillator. Although the absence of spatially resolved hard X-ray observations leaves other possibilities open, a parameterization of the event as a set of seven sequentially firing loops is presented that offers many satisfying explanations of the observations

  18. High resolution solar soft X-ray spectrometer

    International Nuclear Information System (INIS)

    Zhang Fei; Wang Huanyu; Peng Wenxi; Liang Xiaohua; Zhang Chunlei; Cao Xuelei; Jiang Weichun; Zhang Jiayu; Cui Xingzhu

    2012-01-01

    A high resolution solar soft X-ray spectrometer (SOX) payload onboard a satellite is developed. A silicon drift detector (SDD) is adopted as the detector of the SOX spectrometer. The spectrometer consists of the detectors and their readout electronics, a data acquisition unit and a payload data handling unit. A ground test system is also developed to test SOX. The test results show that the design goals of the spectrometer system have been achieved. (authors)

  19. Characteristics of x-rays from a plasma focus operated with neon gas

    Energy Technology Data Exchange (ETDEWEB)

    Zakaullah, M [Department of Physics, Quaid-i-Azam University, 45320 Islamabad (Pakistan); Alamgir, K [Department of Physics, Quaid-i-Azam University, 45320 Islamabad (Pakistan); Shafiq, M [Department of Physics, Quaid-i-Azam University, 45320 Islamabad (Pakistan); Hassan, S M [Department of Physics, Quaid-i-Azam University, 45320 Islamabad (Pakistan); Sharif, M [Department of Physics, Quaid-i-Azam University, 45320 Islamabad (Pakistan); Hussain, S [Department of Physics, Quaid-i-Azam University, 45320 Islamabad (Pakistan); Waheed, A [PINSTECH, PO Box 2151, 44000 Islamabad (Pakistan)

    2002-11-01

    The x-ray emission from a low-energy (2.3 kJ) plasma focus is investigated with neon as the filling gas. Two anode configurations are used in the experiment: the conventional cylindrical anode, and tapered anode slightly toward the open end. The latter geometry enhances soft x-ray emission by an order of magnitude. The emission is pressure dependent and, in both cases, the highest emission is observed at 3-3.5 mbar. For the cylindrical anode, the soft x-ray emission is up to 7 J per shot, which is from a pinched plasma column, 5-6 mm long. For the tapered anode, up to 80 J per shot soft x-ray yield in 4{pi} geometry is recorded, which corresponds to 4% wall plug efficiency. The diameter of the x-ray emission filament is much larger compared with the cylindrical anode. The bulk of emitted radiation is of energy 1.2-1.3 keV, which is thought to arise from recombination of hydrogen-like (Ne x) ions with the low-energy electrons.

  20. Characteristics of x-rays from a plasma focus operated with neon gas

    International Nuclear Information System (INIS)

    Zakaullah, M; Alamgir, K; Shafiq, M; Hassan, S M; Sharif, M; Hussain, S; Waheed, A

    2002-01-01

    The x-ray emission from a low-energy (2.3 kJ) plasma focus is investigated with neon as the filling gas. Two anode configurations are used in the experiment: the conventional cylindrical anode, and tapered anode slightly toward the open end. The latter geometry enhances soft x-ray emission by an order of magnitude. The emission is pressure dependent and, in both cases, the highest emission is observed at 3-3.5 mbar. For the cylindrical anode, the soft x-ray emission is up to 7 J per shot, which is from a pinched plasma column, 5-6 mm long. For the tapered anode, up to 80 J per shot soft x-ray yield in 4π geometry is recorded, which corresponds to 4% wall plug efficiency. The diameter of the x-ray emission filament is much larger compared with the cylindrical anode. The bulk of emitted radiation is of energy 1.2-1.3 keV, which is thought to arise from recombination of hydrogen-like (Ne x) ions with the low-energy electrons

  1. Exospheric Neutral Density at the Earth's subsolar magnetopause deduced from the XMM-Newton X-ray observations

    Science.gov (United States)

    Connor, H. K.; Carter, J. A.

    2017-12-01

    Soft X-rays can be emitted when highly charged solar wind ions and exospheric neutrals exchange electrons. Astrophysics missions, such as XMM-Newton and ROSAT X-ray telescopes, have found that such solar wind charge exchange happens at the Earth's exosphere. The Earth's magnetosphere can be imaged via soft X-rays in order to understand its interaction with solar wind. Consequently, two soft X-ray telescope missions (CuPID and SMILE) are scheduled to launch in 2019 and 2021. They will provide wide field-of-view soft X-ray images of the Earth's dayside magnetosphere. The imagers will track the location and movement of the cusps, magnetopause, and bow shock in response to solar wind variations. To support these missions, an understanding of exospheric neutral density profile is needed. The neutral density is one of the controlling factors of soft X-ray signals. Strong neutral density can help to obtain high-resolution and high-cadence of soft X-ray images. In this study, we estimate the exospheric neutral density at 10 RE subsolar point using XMM X-ray observations, Cluster plasma observations, and OpenGGCM global magnetosphere - ionosphere MHD model. XMM-Newton observes line-of-sight, narrow field-of-view, integrated soft X-ray emissions when it looks through the dayside magnetosphere. OpenGGCM reproduces soft X-ray signals seen by the XMM spacecraft, assuming exospheric neutral density as a function of the neutral density at the 10RE subsolar point and the radial distance. Cluster observations are used to confirm OpenGGCM plasma results. Finally, we deduce the neutral density at 10 RE subsolar point by adjusting the model results to the XMM-Newton soft X-ray observations.

  2. Numerical experiments on plasma focus for soft x-ray yield scaling laws derivation using Lee model

    International Nuclear Information System (INIS)

    Akel, M.

    2012-09-01

    The required plasma parameters of krypton and xenon at different temperatures were calculated, the x-ray emission properties of plasmas were studied, and based on the corona model the suitable temperature range for generating H-like and He-like ions (therefore soft x-ray emissions) of different gases plasma were found. The code is applied to characterize the plasma focus in different plasma focus devices, and for optimizing the nitrogen, oxygen, neon, argon, krypton and xenon soft x-ray yields based on bank, tubes and operating parameters. It is found that the soft x-ray yield increases with changing pressure until it reaches the maximum value for each plasma focus device. Keeping the bank parameters, operational voltage unchanged but systematically changing other parameters, numerical experiments were performed finding the optimum combination of P o , Z o and 'a' for the maximum soft x-ray yield. Thus we expect to increase the soft x-ray yield of plasma focus device several-fold from its present typical operation; without changing the capacitor bank, merely by changing the electrode configuration and the operating pressure. The Lee model code was also used to run numerical experiments on plasma focus devices for optimizing soft x-ray yield with reducing L o , varying L o and 'a' to get engineering designs with maximum soft x-ray yield for these devices at different experimental conditions and gases. Numerical experiments showed the influence of the gas used in plasma focus and its properties on soft x-ray emission and its properties and then on its applications. Scaling laws for soft x-ray of nitrogen, oxygen, neon, argon, krypton and xenon plasma focus, in terms of energy, peak discharge current and focus pinch current were found. Radiative cooling effects are studied indicating that radiative collapse may be observed for heavy noble gases (Ar, Kr, Xe) for pinch currents even below 100 kA. The results show that the line radiation emission and tube voltages have

  3. Numerical experiments on plasma focus for soft x-ray yield scaling laws derivation using Lee model

    International Nuclear Information System (INIS)

    Akel, M.

    2015-01-01

    The required plasma parameters of krypton and xenon at different temperatures were calculated, the x-ray emission properties of plasmas were studied, and based on the corona model the suitable temperature range for generating H-like and He-like ions (therefore soft x-ray emissions) of different gases plasma were found. The code is applied to characterize the plasma focus in different plasma focus devices, and for optimizing the nitrogen, oxygen, neon, argon, krypton and xenon soft x-ray yields based on bank, tubes and operating parameters. It is found that t he soft x-ray yield increases with changing pressure until it reaches the maximum value for each plasma focus device. Keeping the bank parameters, operational voltage unchanged but systematically changing other parameters, numerical experiments were performed finding the optimum combination of Po, z0 and 'a' for the maximum soft x-ray yield. Thus we expect to increase the soft x-ray yield of plasma focus device several-fold from its present typical operation; without changing the capacitor bank, merely by changing the electrode configuration and the operating pressure. The Lee model code was also used to run numerical experiments on plasma focus devices for optimizing soft x-ray yield with reducing Lo, varying z0 and 'a' to get engineering designs with maximum soft x-ray yield for these devices at different experimental conditions and gases. Numerical experiments showed the influence of the gas used in plasma focus and its propor ties on soft x-ray emission and its propor ties and then on its applications. Scaling laws for soft x-ray of nitrogen, oxygen, neon, argon, krypton and xenon plasma focus in terms of energy, peak discharge current and focus pinch current were found. Radiative cooling effects are studied indicating that radiative collapse may be observed for heavy noble gases (Ar, Kr, Xe) for pinch currents even below 100 k A. The results show that the line radiation emission and

  4. [Experimental investigation of laser plasma soft X-ray source with gas target].

    Science.gov (United States)

    Ni, Qi-liang; Gong, Yan; Lin, Jing-quan; Chen, Bo; Cao, Jian-lin

    2003-02-01

    This paper describes a debris-free laser plasma soft X-ray source with a gas target, which has high operating frequency and can produce strong soft X-ray radiation. The valve of this light source is drived by a piezoelectrical ceramic whose operating frequency is up to 400 Hz. In comparison with laser plasma soft X-ray sources using metal target, the light source is debris-free. And it has higher operating frequency than gas target soft X-ray sources whose nozzle is controlled by a solenoid valve. A channel electron multiplier (CEM) operating in analog mode is used to detect the soft X-ray generated by the laser plasma source, and the CEM's output is fed to to a charge-sensitive preamplifier for further amplification purpose. Output charges from the CEM are proportional to the amplitude of the preamplifier's output voltage. Spectra of CO2, Xe and Kr at 8-14 nm wavelength which can be used for soft X-ray projection lithography are measured. The spectrum for CO2 consists of separate spectral lines originate mainly from the transitions in Li-like and Be-like ions. The Xe spectrum originating mainly from 4d-5f, 4d-4f, 4d-6p and 4d-5p transitions in multiply charged xenon ions. The spectrum for Kr consists of separate spectral lines and continuous broad spectra originating mainly from the transitions in Cu-, Ni-, Co- and Fe-like ions.

  5. Current sheath curvature correlation with the neon soft x-ray emission from plasma focus device

    International Nuclear Information System (INIS)

    Zhang, T; Lin, X; Chandra, K A; Tan, T L; Springham, S V; Patran, A; Lee, P; Lee, S; Rawat, R S

    2005-01-01

    The insulator sleeve length is one of the major parameters that can severely affect the neon soft x-ray yield from a plasma focus. The effect of the insulation sleeve length on various characteristic timings of plasma focus discharges and hence the soft x-ray emission characteristics has been investigated using a resistive divider. The pinhole images and laser shadowgraphy are used to explain the observed variation in the average soft x-ray yield (measured using a diode x-ray spectrometer) with variation of the insulator sleeve length. We have found that for a neon filled plasma focus device the change in insulator sleeve length changes the current sheath curvature angle and thus the length of the focused plasma column. The optimized current sheath curvature angle is found to be between 39 0 and 41 0 , at the specific axial position of 6.2-9.3 cm from the cathode support plate, for our 3.3 kJ plasma focus device. A strong dependence of the neon soft x-ray yield on the current sheath curvature angle has thus been reported

  6. Monochromatic X-ray probing of a superdense plasma

    International Nuclear Information System (INIS)

    Pikuz, S.A.; Shelkovenko, T.A.; Romanova, V.M.; Faenov, A.Ya.; Dyakin, V.A.; Pikuz, T.A.

    1995-01-01

    Investigation results are presented of the superdense plasma of an exploding wire by means of a new scheme of X-ray monochromatic probing. The scheme permits not only to obtain the shadow images of bright plasma objects in separate spectral lines with a high spatial resolution but and to lower requirements to a radiation source. Experimental results confirm existence of a small-dense plasma coronae, appeared during the initial stage of a discharge through a wire, and a dense core, existing at the pinch axis in the discharge process. 13 refs.; 3 figs

  7. Detection of nanoflare-heated plasma in the solar corona by the FOXSI-2 sounding rocket

    Science.gov (United States)

    Ishikawa, Shin-nosuke; Glesener, Lindsay; Krucker, Säm; Christe, Steven; Buitrago-Casas, Juan Camilo; Narukage, Noriyuki; Vievering, Juliana

    2017-11-01

    The processes that heat the solar and stellar coronae to several million kelvins, compared with the much cooler photosphere (5,800 K for the Sun), are still not well known1. One proposed mechanism is heating via a large number of small, unresolved, impulsive heating events called nanoflares2. Each event would heat and cool quickly, and the average effect would be a broad range of temperatures including a small amount of extremely hot plasma. However, detecting these faint, hot traces in the presence of brighter, cooler emission is observationally challenging. Here we present hard X-ray data from the second flight of the Focusing Optics X-ray Solar Imager (FOXSI-2), which detected emission above 7 keV from an active region of the Sun with no obvious individual X-ray flare emission. Through differential emission measure computations, we ascribe this emission to plasma heated above 10 MK, providing evidence for the existence of solar nanoflares. The quantitative evaluation of the hot plasma strongly constrains the coronal heating models.

  8. Investigation of plasma dynamics and x-ray emission in'ATON'plasma focus

    International Nuclear Information System (INIS)

    Soliman, H.M.; Masoud, M.M.

    1995-01-01

    The experimental studies on 20 kJ 'Aton' plasma focus device are presented in this paper. The plasma sheath structure has been investigated by means of the measurements of the axial and azimuthal magnetic fields along the coaxial electrodes. The operating gas was hydrogen with pressures in the range of 0.62 torr to 6 torr. The intensity of visible radiation emitted by the plasma sheath was measured as a function of axial distances along the coaxial electrodes. The results showed that the visible radiation intensity is increased with axial distances until a position near the muzzle, then it decreased and has a minimum value at the coaxial electrode muzzle. The main parameters contributing to the behavior of the distribution are the plasma sheath density and the impurities from the eroded materials of the discharge electrodes. An x-ray pulse has been detected along the coaxial electrodes and extended up to the expansion chamber. At a distance near the muzzle two x-ray pulses have been detected, the second one has intensity relative to the first one with time lag of 11μs. 8 fig

  9. Set of instruments for solar EUV and soft X-ray monitoring onboard satellite Coronas-Photon

    Science.gov (United States)

    Kotov, Yury; Kochemasov, Alexey; Kuzin, Sergey; Kuznetsov, Vladimir; Sylwester, Janusz; Yurov, Vitaly

    Coronas-Photon mission is the third satellite of the Russian Coronas program on solar activity observation. The main goal of the "Coronas-Photon" is the study of solar hard electromagnetic radiation in the wide energy range from UV up to high energy gamma-radiation (2000MeV). Scientific payload for solar radiation observation consists of three types of instruments: Monitors (Natalya-2M, Konus-RF, RT-2, Penguin-M, BRM, PHOKA, Sphin-X, SOKOL spectral and timing measurements of full solar disk radiation have timing in flare/burst mode up to one msec. Instruments Natalya-2M, Konus-RF, RT-2 will cover the wide energy range of hard X-rays and soft gamma-rays (15keV to 2000MeV) and will together constitute the largest area detectors ever used for solar observations. Detectors of gamma-ray monitors are based on structured inorganic scintillators. For X-ray and EUV monitors the scintillation phoswich detectors, gas proportional counter, CdZnTe assembly and filter-covered Si-diodes are used. Telescope-spectrometer TESIS for imaging solar spectroscopy in X-rays has angular resolution up to 1arcsec in three spectral lines. Satellite platform and scientific payload is under construction to be launched in autumn 2008. Satellite orbit is circular with initial height 550km and inclination 82.5degrees. Accuracy of the spacecraft orientation to the Sun is better 3arcmin. In the report the capability of PHOKA, SphinX, SOKOL and TESIS as well as the observation program are described and discussed.

  10. Solar flare hard and soft x ray relationship determined from SMM HXRBS and BCS data

    Science.gov (United States)

    Toot, G. David

    1989-01-01

    The exact nature of the solar flare process is still somewhat a mystery. A key element to understanding flares if the relationship between the hard x rays emitted by the most energetic portions of the flare and the soft x rays from other areas and times. This relationship was studied by comparing hard x ray light curved from the Hard X-Ray Burst Spectrometer (HXRBS) with the soft x ray light curve and its derivation from the Bent Crystal Spectrometer (BCS) which is part of the X-Ray Polychrometer (XRP), these instruments being on the Solar Maximum Mission spacecraft (SMM). Data sample was taken from flares observed with the above instruments during 1980, the peak of the previous maximum of solar activity. Flares were chosen based on complete coverage of the event by several instruments. The HXRBS data covers the x ray spectrum from about 25 keV to about 440 keV in 15 spectral channels, while the BCS data used covers a region of the Spectrum around 3 angstroms including emission from the Ca XIX ion. Both sets of data were summed over their spectral ranges and plotted against time at a maximum time resolution of around 3 seconds. The most popular theory of flares holds that a beam of electrons produces the hard x rays by bremsstrahlung while the soft x rays are the thermal response to this energy deposition. The question is whether the rate of change of soft x ray emission might reflect the variability of the electron beam and hence the variability of the hard x rays. To address this, we took the time derivative of the soft x ray light curve and compared it to the hard flares, 12 of them showed very closed agreement between the soft x ray derivative and the hard x ray light curve. The other five did not show this behavior but were similar to each other in general soft x ray behavior. Efforts to determine basic differences between the two kinds of flares continue. In addition the behavior of soft x ray temperature of flares was examined.

  11. A study on the fusion reactor - Development of x-ray spectrometer for diagnosis of tokamak plasma

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Hong Young; Choi, Duk In; Seo, Sung Hun; Kwon, Gi Chung; Jun, Sang Jin; Heo, Sung Hoi; Lee, Chan Hui [Korea Advanced Institute of Science and Technolgoy, Taejon (Korea, Republic of)

    1996-09-01

    This report of research is on the development of X-ray Photo-Electron Spectrometer (PES) for diagnosis of tokamak plasma. The spectrometer utilizes the fact that the energy of photo-electron is given by the difference between the energy of X-ray and the binding energy of materials. In the research of this year, we constructed two spectrometers; one is operated in KAIST tokamak and the other in KT1 tokamak. In addition, we reviewed the characteristics of the x-ray filter, the photo-electric effect of carbon foils and the detection efficiency of MCP and x-ray radiation of plasma. We measured the x-ray radiation in tokamak and diagnosed the qualitative plasma parameters from the analysis of data. The major interesting plasma parameters, which we can diagnose with the spectrometer, are the electron temperature, Z{sub eff}, the spatial distribution of x-ray radiation and etc. 27 refs., 2 tabs., 20 figs. (author)

  12. Columbia University OSO-8 instrument for stellar and solar X-ray spectroscopy and polarimetry

    Energy Technology Data Exchange (ETDEWEB)

    Wolff, R S [Columbia Univ., New York (USA). Columbia Astrophysics Lab.

    1976-08-01

    A spectrometer and a polarimeter consisting of large-area panels of mosaic crystals have been constructed and prepared for use in the OSO-8 satellite. The instrumentation is planned for study of stellar and solar X-ray spectra between 1.8-8 keV and stellar X-ray polarization at 2.6 keV. Aspects of the design which enable the instrument to make measurements of the diverse range of stellar and solar phenomena are described. Some of the unique features, such as high sensitivity, high temporal resolution, and spectral range, are discussed. The applicability of the spectrometer and polarimeter to various current problems in X-ray astronomy is considered.

  13. Compact tunable Compton x-ray source from laser-plasma accelerator and plasma mirror

    International Nuclear Information System (INIS)

    Tsai, Hai-En; Wang, Xiaoming; Shaw, Joseph M.; Li, Zhengyan; Zgadzaj, Rafal; Henderson, Watson; Downer, M. C.; Arefiev, Alexey V.; Zhang, Xi; Khudik, V.; Shvets, G.

    2015-01-01

    We present an in-depth experimental-computational study of the parameters necessary to optimize a tunable, quasi-monoenergetic, efficient, low-background Compton backscattering (CBS) x-ray source that is based on the self-aligned combination of a laser-plasma accelerator (LPA) and a plasma mirror (PM). The main findings are (1) an LPA driven in the blowout regime by 30 TW, 30 fs laser pulses produce not only a high-quality, tunable, quasi-monoenergetic electron beam, but also a high-quality, relativistically intense (a 0 ∼ 1) spent drive pulse that remains stable in profile and intensity over the LPA tuning range. (2) A thin plastic film near the gas jet exit retro-reflects the spent drive pulse efficiently into oncoming electrons to produce CBS x-rays without detectable bremsstrahlung background. Meanwhile, anomalous far-field divergence of the retro-reflected light demonstrates relativistic “denting” of the PM. Exploiting these optimized LPA and PM conditions, we demonstrate quasi-monoenergetic (50% FWHM energy spread), tunable (75–200 KeV) CBS x-rays, characteristics previously achieved only on more powerful laser systems by CBS of a split-off, counter-propagating pulse. Moreover, laser-to-x-ray photon conversion efficiency (∼6 × 10 −12 ) exceeds that of any previous LPA-based quasi-monoenergetic Compton source. Particle-in-cell simulations agree well with the measurements

  14. X-ray emission from plasmas created by smoothed KrF laser irradiation

    International Nuclear Information System (INIS)

    Aglitskiy, Y.; Lehecka, T.; Deniz, A.; Hardgrove, J.; Seely, J.; Brown, C.; Feldman, U.; Pawley, C.; Gerber, K.; Bodner, S.; Obenschain, S.; Lehmberg, R.; McLean, E.; Pronko, M.; Sethian, J.; Stamper, J.; Schmitt, A.; Sullivan, C.; Holland, G.; Laming, M.

    1996-01-01

    The x-ray emission from plasmas created by the Naval Research Laboratory Nike KrF laser [Phys. Plasmas 3, 2098 (1996) ] was characterized using imaging and spectroscopic instruments. The laser wavelength was 1/4 μm, and the beams were smoothed by induced spatial incoherence (ISI). The targets were thin foils of CH, aluminum, titanium, and cobalt and were irradiated by laser energies in the range 100 endash 1500 J. A multilayer mirror microscope operating at an energy of 95 eV recorded images of the plasma with a spatial resolution of 2 μm. The variation of the 95 eV emission across the 800 μm focal spot was 1.3% rms. Using a curved crystal imager operating in the 1 endash 2 keV x-ray region, the density, temperature, and opacity of aluminum plasmas were determined with a spatial resolution of 10 μm perpendicular to the target surface. The spectral line ratios indicated that the aluminum plasmas were relatively dense, cool, and optically thick near the target surface. The absolute radiation flux was determined at 95 eV and in x-ray bandpasses covering the 1 endash 8 keV region. The electron temperature inferred from the slope of the x-ray flux versus energy data in the 5 endash 8 keV region was 900 eV for an incident laser energy of 200 J and an intensity of ≅10 13 W/cm 2

  15. X-ray spectroscopy from fusion plasmas

    International Nuclear Information System (INIS)

    Glenzer, S H.

    1998-01-01

    Our understanding of laser energy coupling into laser-driven inertial confinement fusion targets largely depends on our ability to accurately measure and simulate the plasma conditions in the underdense corona and in high density capsule implosions. X-ray spectroscopy is an important technique which has been applied to measure the total absorption of laser energy into the fusion target, the fraction of laser energy absorbed by hot electrons, and the conditions in the fusion capsule in terms of density and temperature. These parameters provide critical benchmarking data for performance studies of the fusion target and for radiation-hydrodynamic and laser-plasma interaction simulations. Using x-ray spectroscopic techniques for these tasks has required its application to non-standard conditions where kinetics models have not been extensively tested. In particular, for the conditions in high density implosions, where electron temperatures achieve 1 - 2 keV and electron densities reach 10 24 cm -3 evolving on time scales of 21 cm -3 and which am independently diagnosed with Thomson scattering and stimulated Raman scattering. We find that kinetics modeling is in good agreement with measured intensities of the dielectronic satellites of the He-β line (n= l-3) of Ar XVII. Applying these findings to the experimental results of capsule implosions provides additional evidence of temperature gradients at peak compression

  16. X-ray emission from hot plasma

    International Nuclear Information System (INIS)

    Hayakawa, Satio; Kato, Takako.

    1979-01-01

    X-ray emission from hot plasmas is discussed with a critical review of different theories. The results given in the present paper are complementary to those given by Kato in the sense that the present paper is introductory to the paper by Kato. The contents of the present paper are; 1. Introduction 2. Ionization and Recombination Rate Coefficients 3. Relative Abundances of Ions 4. Intensity and Spectra of Radiation 5. Comparison with Earlier Results 6. Emission and Absorption Lines (author)

  17. X-ray backlighting of two-wire Z-pinch plasma using X-pinch

    International Nuclear Information System (INIS)

    Tong, Zhao; Xiao-Bing, Zou; Ran, Zhang; Xin-Xin, Wang

    2010-01-01

    Two 50-μm Mo wires in parallel used as a Z-pinch load are electrically exploded with a pulsed current rising to 275 kA in 125 ns and their explosion processes are backlighted using an X-pinch as an x-ray source. The backlighting images show clearly the processes similar to those occurring in the initial stages of a cylindrical wire-array Z-pinch, including the electric explosion of single wires characterised by the dense wire cores surrounded by a low-density coronal plasma, the expansion of the exploding wire, the sausage instability (m = 0) in the coronal plasma around each wire, the motion of the coronal plasma as well as the wire core toward the current centroid, the formation of the precursor plasma column with a twist structure something like that of higher mode instability, especially the kink instability (m = 1). (fluids, plasmas and electric discharges)

  18. Optimization of neon soft X-ray emission from 200 J plasma focus device for application in soft X-ray lithography

    International Nuclear Information System (INIS)

    Kalaiselvi, S.M. P.; Tan, T.L.; Talebitaher, A.; Lee, Paul; Rawat, R.S.

    2014-01-01

    The Fast Miniature Plasma Focus (FMPF) device is basically made up of coaxial electrodes with centrally placed anode and six cathode rods surrounding them concentrically. They are enclosed in a vacuum chamber, filled with low pressure operating gas. However, in our experiments, these cathode rods were removed to investigate the influence of them on neon soft X-ray (SXR) and hard X-ray (HXR) emission from the device. On removal of cathode rods, the cathode base plate serves as cathode and the plasma sheath is formed between the anode and the base plate of cathode. Neon was used as the operating gas for our experiments and the FMPF device used is of 235 J energy capacities. The experimental results showed that the FMPF device was able to focus better and the SXR emission efficiency was five times higher without cathode rods than with cathode rods. On the contrary, HXR emission did not vary with and without cathode rods. This observed phenomenon was further cross-checked through imaging of plasma dynamics, with and without cathode rods. FMPF device consists of 4 Pseudo Spark Gap (PSG) switches, which need to operate synchronously to deliver high voltage from capacitors to the anode. It was also seen that, the presence or absence of cathode rods also influence the synchronous operation of PSG switches. It also implies that this is one definite way to optimize the SXR emission from the FMPF device. This study reveals an important finding that, cathode rods play a vital role in the formation of plasma sheath with consequential influence on the radiation emission from plasma focus devices. Enhancement of the X-ray emission from this device is definitely a stepping stone in the realization of this device for industrial applications such as X-ray lithography for semiconductor industries. (author)

  19. Experimental device for the X-ray energetic distribution measurement in a tokamak plasma

    International Nuclear Information System (INIS)

    Perez-Navarro, A.

    1977-01-01

    An experimental system to measure the X-ray spectrum in a tokamak plasma is described, emphasizing its characteristics: resolution, dead time and the pulse pile-up distortion effects on the X-ray spectra. (author) [es

  20. [The property and applications of the photovoltaic solar panel in the region of diagnostic X-ray].

    Science.gov (United States)

    Hirota, Jun'ichi; Tarusawa, Kohetsu; Kudo, Kohsei

    2010-10-20

    In this study, the sensitivity in the diagnostic X-ray region of the single crystalline Si photovoltaic solar panel, which is expected to grow further, was measured by using an X-ray tube. The output voltage of the solar panel was clearly proportional to the tube voltage and a good time response in the irradiation time setting of the tube was measured. The factor which converts measured voltage to irradiation dose was extracted experimentally using a correction filter to investigate the ability of the solar panel as a dose monitor. The obtained conversion factors were N(S) = 13 ± 1[µV/µSv/s] for the serial and N(P) = 58 ± 2[µV/µSv/s] for the parallel connected solar panels, both with the Al 1 mm + Cu 0.1 mm correction filter, respectively. Therefore, a good dose dependence of the conversion factor was confirmed by varying the distance between the X-ray tube and the solar panel with that filter. In conclusion, a simple extension of our results pointed out the potential of a new concept of measurements using, for example, the photovoltaic solar panel, the direct dose measurement from X-ray tube and real time estimation of the exposed dose in IVR.

  1. A development of laser-plasma-based soft x-ray microscope system

    International Nuclear Information System (INIS)

    Nam, Ki Yong; Kim, Kyong Woo; Kim, Kyu Gyeom; Kwon, Young Man; Yoon, Kwon Ha

    2003-01-01

    Soft x-ray nano-imaging microscopy system for biomedical application with a high resolution about 50 nm has been designed and described, and its integrated techniques also have been studied. The system is mainly composed of soft x-ray generation system, nano-scaled control system, x-ray optical device like a condenser or object mirror, a CCD camera coupled with multichannel plate (MCP) and vacuum system. In the system, soft x-ray is generated from the laser-based plasma by focusing Nd:YAG laser beam on tantalum (Ta) target. In an x-ray optical system, a wolter mirror has been considering condensing the x-ray beam on a biological specimen and zone plate was adapted as an object mirror. A Si 3 N 4 was used as specimen holder for keeping a biological sample alive in atmosphere conditions. A back-illuminated-CCD camera coupled with multichannel plate was determined to set up.

  2. A development of laser-plasma-based soft x-ray microscope system

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Ki Yong; Kim, Kyong Woo; Kim, Kyu Gyeom; Kwon, Young Man; Yoon, Kwon Ha [X-ray Microscopy Research Center, Wonkwang University, Iksan (Korea, Republic of)

    2003-07-01

    Soft x-ray nano-imaging microscopy system for biomedical application with a high resolution about 50 nm has been designed and described, and its integrated techniques also have been studied. The system is mainly composed of soft x-ray generation system, nano-scaled control system, x-ray optical device like a condenser or object mirror, a CCD camera coupled with multichannel plate (MCP) and vacuum system. In the system, soft x-ray is generated from the laser-based plasma by focusing Nd:YAG laser beam on tantalum (Ta) target. In an x-ray optical system, a wolter mirror has been considering condensing the x-ray beam on a biological specimen and zone plate was adapted as an object mirror. A Si{sub 3}N{sub 4} was used as specimen holder for keeping a biological sample alive in atmosphere conditions. A back-illuminated-CCD camera coupled with multichannel plate was determined to set up.

  3. Design of solar cell materials via soft X-ray spectroscopy

    DEFF Research Database (Denmark)

    Himpsel, F.J.; Cook, P.L.; de la Torre, G.

    2013-01-01

    This overview illustrates how spectroscopy with soft X-rays can assist the development of new materials and new designs for solar cells. The starting point is the general layout of a solar cell, which consists of a light absorber sandwiched between an electron donor and an electron acceptor....... There are four relevant energy levels that can be measured with a combination of X-ray absorption spectroscopy and photoelectron spectroscopy, as illustrated for an organic dye as absorber attached to a p-doped diamond film as donor. Systematic measurements of organometallic dyes (phthalocyanines and porphyrins......) as a function of the metal atom are presented for the metal 2p and N 1s absorption edges. In combination with density functional theory one can discern trends that are useful for tailoring absorber molecules. A customized porphyrin molecule is investigated that combines an absorber with a donor and a linker...

  4. X-Ray Flare Oscillations Track Plasma Sloshing along Star-disk Magnetic Tubes in the Orion Star-forming Region

    Science.gov (United States)

    Reale, Fabio; Lopez-Santiago, Javier; Flaccomio, Ettore; Petralia, Antonino; Sciortino, Salvatore

    2018-03-01

    Pulsing X-ray emission tracks the plasma “echo” traveling in an extremely long magnetic tube that flares in an Orion pre-main sequence (PMS) star. On the Sun, flares last from minutes to a few hours and the longest-lasting ones typically involve arcades of closed magnetic tubes. Long-lasting X-ray flares are observed in PMS stars. Large-amplitude (∼20%), long-period (∼3 hr) pulsations are detected in the light curve of day-long flares observed by the Advanced CCD Imaging Spectrometer on-board Chandra from PMS stars in the Orion cluster. Detailed hydrodynamic modeling of two flares observed on V772 Ori and OW Ori shows that these pulsations may track the sloshing of plasma along a single long magnetic tube, triggered by a sufficiently short (∼1 hr) heat pulse. These magnetic tubes are ≥20 solar radii long, enough to connect the star with the surrounding disk.

  5. X-ray pinhole camera setups used in the Atomki ECR Laboratory for plasma diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Rácz, R., E-mail: rracz@atomki.hu; Biri, S.; Pálinkás, J. [Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/C, H-4026 Debrecen (Hungary); Mascali, D.; Castro, G.; Caliri, C.; Gammino, S. [Instituto Nazionale di Fisica Nucleare—Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania (Italy); Romano, F. P. [Instituto Nazionale di Fisica Nucleare—Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania (Italy); CNR, Istituto per i Beni Archeologici e Monumentali, Via Biblioteca 4, 95124 Catania (Italy)

    2016-02-15

    Imaging of the electron cyclotron resonance (ECR) plasmas by using CCD camera in combination with a pinhole is a non-destructive diagnostics method to record the strongly inhomogeneous spatial density distribution of the X-ray emitted by the plasma and by the chamber walls. This method can provide information on the location of the collisions between warm electrons and multiple charged ions/atoms, opening the possibility to investigate the direct effect of the ion source tuning parameters to the plasma structure. The first successful experiment with a pinhole X-ray camera was carried out in the Atomki ECR Laboratory more than 10 years ago. The goal of that experiment was to make the first ECR X-ray photos and to carry out simple studies on the effect of some setting parameters (magnetic field, extraction, disc voltage, gas mixing, etc.). Recently, intensive efforts were taken to investigate now the effect of different RF resonant modes to the plasma structure. Comparing to the 2002 experiment, this campaign used wider instrumental stock: CCD camera with a lead pinhole was placed at the injection side allowing X-ray imaging and beam extraction simultaneously. Additionally, Silicon Drift Detector (SDD) and High Purity Germanium (HPGe) detectors were installed to characterize the volumetric X-ray emission rate caused by the warm and hot electron domains. In this paper, detailed comparison study on the two X-ray camera and detector setups and also on the technical and scientific goals of the experiments is presented.

  6. X-ray pinhole camera setups used in the Atomki ECR Laboratory for plasma diagnostics.

    Science.gov (United States)

    Rácz, R; Biri, S; Pálinkás, J; Mascali, D; Castro, G; Caliri, C; Romano, F P; Gammino, S

    2016-02-01

    Imaging of the electron cyclotron resonance (ECR) plasmas by using CCD camera in combination with a pinhole is a non-destructive diagnostics method to record the strongly inhomogeneous spatial density distribution of the X-ray emitted by the plasma and by the chamber walls. This method can provide information on the location of the collisions between warm electrons and multiple charged ions/atoms, opening the possibility to investigate the direct effect of the ion source tuning parameters to the plasma structure. The first successful experiment with a pinhole X-ray camera was carried out in the Atomki ECR Laboratory more than 10 years ago. The goal of that experiment was to make the first ECR X-ray photos and to carry out simple studies on the effect of some setting parameters (magnetic field, extraction, disc voltage, gas mixing, etc.). Recently, intensive efforts were taken to investigate now the effect of different RF resonant modes to the plasma structure. Comparing to the 2002 experiment, this campaign used wider instrumental stock: CCD camera with a lead pinhole was placed at the injection side allowing X-ray imaging and beam extraction simultaneously. Additionally, Silicon Drift Detector (SDD) and High Purity Germanium (HPGe) detectors were installed to characterize the volumetric X-ray emission rate caused by the warm and hot electron domains. In this paper, detailed comparison study on the two X-ray camera and detector setups and also on the technical and scientific goals of the experiments is presented.

  7. Polarization of X-ray lines emitted from plasma-focus discharges; Problems of interpretation

    International Nuclear Information System (INIS)

    Jakubowski, L.

    2002-01-01

    In high current pulse discharges of the Plasma Focus (PF) type, inside the collapsing pinch column, there are formed local micro-regions of high-density and high-temperature plasma, so-called hot spots. Individual hot spots are separated in space and time. Each hot spot is characterized by its specific electron concentration and temperature, as well as by the emission of X-ray lines with different polarization. When numerous hot spots are produced it is impossible to determine local plasma parameters and to interpret the polarization effects. To eliminate this problem this study was devoted to the realization of PF-type discharges with single hot spot only. It has been achieved by a choice of the electrode configuration, which facilitated the formation of a single hot spot emitting intense X-ray lines. At the chosen experimental conditions it was possible to determine local plasma parameters and to demonstrate evident differences in the polarization of the observed X-ray lines. (author)

  8. X-ray polarization studies of plasma focus experiments with a single hot spots

    International Nuclear Information System (INIS)

    Jakubowski, L.; Sadowski, M.J.; Baronova, E.O.

    2004-01-01

    In high current pulse discharges of the plasma focus (PF) type, inside the collapsing pinch column, there are formed local micro-regions of high-density and high-temperature plasma, so-called hot spots. Individual hot spots are separated in space and time. Each hot spot is characterized by its specific electron concentration and temperature, as well as by the emission of x-ray lines with different polarization. When numerous hot spots are produced it is impossible to determine local plasma parameters and to interpret the polarization effects. To eliminate this problem this study was devoted to the realization of PF-type discharges with single hot spot only. It has been achieved by a choice of the electrode configuration, which facilitated the formation of a single hot spot emitting intense x-ray lines. At the chosen experimental conditions it was possible to determine local plasma parameters and to demonstrate evident differences in the polarization of the observed x-ray lines. (author)

  9. Polarization of x-ray lines emitted from plasma-focus discharges; Problems of interpretation

    International Nuclear Information System (INIS)

    Jakubowski, L.; Sadowski, M.J.; Baronova, E.O.

    2003-01-01

    In high current pulse discharges of the Plasma Focus (PF) type, inside the collapsing pinch column, there are formed local micro-regions of high-density and high-temperature plasma, so-called hot spots. Individual hot spots are separated in space and time. Each hot spot is characterized by its specific electron concentration and temperature, as well as by the emission of X-ray lines with different polarization. When numerous hot spots are produced it is impossible to determine local plasma parameters and to interpretate the polarization effects. To eliminate this problem this study was devoted to the realization of PF-type discharges with single hot spot only. It has been achieved by a choice of the electrode configuration, which facilitated the formation of a single hot spot emitting intense X-ray lines. At the chosen experimental conditions it was possible to determine local plasma parameters and to demonstrate evident differences in the polarization of the observed X-ray lines. (author)

  10. X-ray spectroscopy of plasmas created by the Nike KrF laser

    International Nuclear Information System (INIS)

    Aglitskiy, Y.; Lehecka, T.; Deniz, A.; Hardgrove, J.; Seely, J.; Brown, C.; Feldman, U.; Pawley, C.; Gerber, K.; Bodner, S.; Obenschain, S.; Lehmberg, R.; McLean, E.; Pronko, M.; Sethian, J.; Stamper, J.; Schmitt, A.; Sullivan, C.; Holland, G.; Laming, M.

    1997-01-01

    The x-ray emission from plasmas created by the Naval Research Laboratory Nike KrF laser was characterized using spectroscopic instruments. The targets were thin foils of aluminum and titanium and were irradiated by laser energies in the range 100 endash 1500 J. Using a spherical-crystal imaging spectrometer operating in the 1 endash 2 keV x-ray region, the density, temperature, and opacity of aluminum plasmas were determined with a spatial resolution of 10 μm in the direction perpendicular to the target surface. The spectral line ratios indicated that the aluminum plasmas were relatively dense, cool, and optically thick near the target surface

  11. Positron Source from Betatron X-rays Emitted in a Plasma Wiggler

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D.K.; Clayton, C.E.; Huang, C.; Joshi, C.; Lu, W.; Marsh, K.A.; Mori, W.B.; Zhou, M.; /UCLA; Barnes, C.D.; Decker, F.J.; Hogan, M.J.; Iverson, R.H.; Krejcik, P.; O' Connell, C.L.; Siemann, R.; Walz, D.R.; /SLAC; Deng, S.; Katsouleas, T.C.; Muggli, P.; Oz, E.; /Southern California U.

    2006-04-21

    In the E-167 plasma wakefield accelerator (PWFA) experiments in the Final Focus Test Beam (FFTB) at the Stanford Linear Accelerator Center (SLAC), an ultra-short, 28.5 GeV electron beam field ionizes a neutral column of Lithium vapor. In the underdense regime, all plasma electrons are expelled creating an ion column. The beam electrons undergo multiple betatron oscillations leading to a large flux of broadband synchrotron radiation. With a plasma density of 3 x 10{sup 17}cm{sup -3}, the effective focusing gradient is near 9 MT/m with critical photon energies exceeding 50 MeV for on-axis radiation. A positron source is the initial application being explored for these X-rays, as photo-production of positrons eliminates many of the thermal stress and shock wave issues associated with traditional Bremsstrahlung sources. Photo-production of positrons has been well-studied; however, the brightness of plasma X-ray sources provides certain advantages. In this paper, we present results of the simulated radiation spectra for the E-167 experiments, and compute the expected positron yield.

  12. X-ray optical diagnostic of laser produced plasmas for nuclear fusion and X-ray lasers

    Energy Technology Data Exchange (ETDEWEB)

    Butzbach, R.

    2001-07-01

    In the present work, the conception, design and appliance of toroidally bent crystals for the X-ray optical diagnostics of laser produced plasmas is discussed. The first part of this work deals with the development, design and characterization of an X-Ray microscope for the observation of Rayleigh-Taylor instabilities, which act against the confinement and ignition of the fuel in the inertial confinement fusion process. The aim of the second part of the present work was the diagnostic of the lasing medium for amplified spontaneous emission close to the water window. For this purpose, an one-dimensionally (1-D) imaging X-ray spectrometer based on toroidally bent quartz crystals was developed for the observation of the Ni-like 4f-3d transition of Yb, Hf, Ta, and W ions, which should be related to the amplified 4d-4p emission, since the 4f niveau is very close to the 4d niveau. Thus, the 4f-3d transition can serve as an indicator for the population of the 4d niveau. (orig.)

  13. Sub-second pulsations simultaneously observed at microwaves and hard X-rays in a solar burst

    International Nuclear Information System (INIS)

    Takakura, T.; Degaonkar, S.S.; Nitta, N.; Ohki, N.

    1982-11-01

    Sub-second time structures have been found in the emissions during solar bursts in mm-waves and, independently, in hard X-rays. However, simultaneous observations of such fast time structure in mm radio and X-ray ranges has not been available so far. Accordingly, coordinated observations of solar bursts in November 1981 with a high time resolution of a few milliseconds were planned. The hard X-rays (30-40 KeV were observed with hard X-ray monitor (HXM) aboard the Hinotori Satellite with a time resolution of 7.81 ms and the radio emissions were observed on the ground with 45ft dish at Itapetinga Radio Observatory with a high time resolution (1 ms) and high sensitivities at 22 GHz and 44 GHz, supplemented by a patrol observation at 7 GHz with time resolution of 100 ms. The pulsations repeated with a period of about 300 ms. The physical implication of the good correlation is not clear at this stage, but it may give a clue to the understanding of the high energy phenomena occuring during the solar flares. (Author) [pt

  14. Generation of plasma X-ray sources via high repetition rate femtosecond laser pulses

    Science.gov (United States)

    Baguckis, Artūras; Plukis, Artūras; Reklaitis, Jonas; Remeikis, Vidmantas; Giniūnas, Linas; Vengris, Mikas

    2017-12-01

    In this study, we present the development and characterization of Cu plasma X-ray source driven by 20 W average power high repetition rate femtosecond laser in ambient atmosphere environment. The peak Cu- Kα photon flux of 2.3 × 109 photons/s into full solid angle is demonstrated (with a process conversion efficiency of 10-7), using pulses with peak intensity of 4.65 × 1014 W/cm2. Such Cu- Kα flux is significantly larger than others found in comparable experiments, performed in air environment. The effects of resonance plasma absorption process, when optimized, are shown to increase measured flux by the factor of 2-3. The relationship between X-ray photon flux and plasma-driving pulse repetition rate is quasi-linear, suggesting that fluxes could further be increased to 1010 photons/s using even higher average powers of driving radiation. These results suggest that to fully utilize the potential of high repetition rate laser sources, novel target material delivery systems (for example, jet-based ones) are required. On the other hand, this study demonstrates that high energy lasers currently used for plasma X-ray sources can be conveniently and efficiently replaced by high average power and repetition rate laser radiation, as a way to increase the brightness of the generated X-rays.

  15. Plasma X-ray sources powered by megajoule magnetocumulative generators

    Energy Technology Data Exchange (ETDEWEB)

    Popkov, N F; Averchenkov, V Ya; Pikar` , A S; Ryaslov, E A; Kargin, V I; Lazarev, S A; Borodkov, V V; Nazarenko, S T; Makartsev, G F [All-Russian Research Inst. of Experimental Physics, Sarov (Russian Federation). Russian Federal Nuclear Center

    1997-12-31

    Experiments using magnetocumulative generators (MCGs) were performed to power three different types of high-energy-density plasma discharges suitable for intense x-ray generation. These included the H-pressed discharge, the capillary z-pinch, and the {theta}-pinch. The MCGs were operated both with and without plasma opening switches. The characteristic currents were approximately 10 MA and characteristic time scales approximately 1 {mu}s. (author). 7 figs., 3 refs.

  16. The Soft X-ray Telescope for Solar-A - Design evolution and lessons learned

    Science.gov (United States)

    Bruner, Marilyn E.

    1992-01-01

    The Japanese Solar-A satellite mission's Soft X-ray Telescope uses grazing-incidence optics, a CCD detector, and a pair of filter wheels for wavelength selection. A coaxially-mounted visible-light lens furnished sunspot and magnetic plage images, together with aspect information which aids in aligning the soft X-ray images with those from the satellite's Hard X-ray Telescope. Instrument electronics are microprocessor-based, and imbedded in a tightly integrated distributed system. Control software is divided between the instrument microprocessor and the spacecraft control computer.

  17. A new sounding rocket payload for solar plasma studies

    Science.gov (United States)

    Bruner, Marilyn E.; Brown, William A.; Appert, Kevin L.

    1989-01-01

    A sounding rocket payload developed for studies of high-temperature plasmas associated with solar active regions and flares is described. The payload instruments will record both spectra and images in the UV, EUV, and soft X-ray regions of the spectrum. The instruments, including the Dual Range Spectrograph, the Flat Field Soft X-ray Spectrograph, the Normal Incidence Soft X-ray Imager, the UV Filtergraph, and the H-alpha Imaging system, are described. Attention is also given to the new structural system of the payload, based on a large optical table suspended within the payload cavity, which will support the optical elements in their correct positions and orientations and will maintain these alignments throughout the rocket launch environment.

  18. Review of x-ray spectroscopy from laser-produced plasmas

    International Nuclear Information System (INIS)

    Kauffman, R.L.

    1987-09-01

    Recent progress in x-ray spectroscopy from laser plasmas is reviewed. Advances in the use of K-shell spectra as a diagnostic tool is discussed. Much activity in understanding complex spectra especially from Ne I and Ni I isoelectronic series have been made. Much of the progress has been due to observation of amplification from Δn = O transitions from these configurations. The spectroscopy will be discussed and examples of spectra of the amplified lines will be shown. Finally, recent work on using x-ray spectroscopy to diagnose high density implosions will be discussed. 33 refs

  19. Neutron and X-ray emission studies in a low energy plasma focus

    Energy Technology Data Exchange (ETDEWEB)

    Zakaullah, M. [Quaid-i-Azam Univ., Islamabad (Pakistan). Dept. of Physics; Murtaza, G. [Quaid-i-Azam Univ., Islamabad (Pakistan). Dept. of Physics; Qamar, S. [Quaid-i-Azam Univ., Islamabad (Pakistan). Dept. of Physics; Ahmad, I. [Quaid-i-Azam Univ., Islamabad (Pakistan). Dept. of Physics; Beg, M.M. [Quaid-i-Azam Univ., Islamabad (Pakistan). Dept. of Physics

    1996-03-01

    In a low energy Mather-type plasma focus energized by a single 32 {mu}F capacitor, the X-ray and neutron emission is investigated using time-integrated and time-resolved detectors. The X-ray emission profile has a width (FWHM) of 40-50 ns. The neutron emission profile is broader compared to the X-ray emission profile and also delayed by 30-40 ns. To identify different regimes of X-ray emission, an X-ray pin-hole camera along with different absorption filters is employed. While the X-ray emission is high within a narrow pressure range of 2.0-2.5 mbar, the neutron emission is intense for a wider range of 1.0-4.5 mbar. The intense X-ray emission seems to originate from the axially moving shock wave. These results also indicate rather different production mechanisms for X-ray and neutron emission. Also on comparing the X-ray images with Al(2 {mu}m), Al(5 {mu}m), Al(9 {mu}m) filters, we find that the bulk of X-rays from the focus filament have energies less than 2 keV. (orig.).

  20. High resolution X-ray spectromicroscopy of laser produced plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Faenov, A.Ya. [Multi-charged Ions Spectra Data Center of VNIIFTRI (MISDC), Mendeleevo, Moscow region, (Russian Federation)

    2000-01-01

    In recent years new classes of X-ray spectroscopic instruments possessing both dispersive and focusing properties have been manufactured. Their principal advantage over more traditional instruments is that they combine very high luminosity with high spatial resolution, while preserving the highest possible spectral resolution of their dispersive elements. These instruments opened up the registration of plasmas in new regimes and surroundings. The measurements delivered new information about the properties of even previously studied traditional plasma objects (e.g. ns-laser produced plasmas). Also the detailed investigation of relatively new plasma laboratory sources with very small dimensions and low energy content (e.g. mJ fs-laser pulses) became possible. The purpose of this report is to give a short review of the experimental and theoretical results obtained in the past few years by MISDC (Multi-charged Ions Spectra Data Center) research team in the field of X-ray spectroscopy of a laser-produced plasma. Experimental spectra have been obtained at various laser installations with nanosecond, sub-nanosecond, picosecond and sub-picosecond pulses interacting with solid, gaseous or cluster targets in collaborations with research teams from Russia, USA, Germany, France, Poland, Belgium, Italy, China and Israel. Practically all results have been obtained with the help of spectrographs with spherically bent mica crystals operating in FSSR-1D, 2D schemes. (author)

  1. A final report to the Laboratory Directed Research and Development committee on Project 93-ERP-075: ''X-ray laser propagation and coherence: Diagnosing fast-evolving, high-density laser plasmas using X-ray lasers''

    International Nuclear Information System (INIS)

    Wan, A.S.; Cauble, R.; Da Silva, L.B.; Libby, S.B.; Moreno, J.C.

    1996-02-01

    This report summarizes the major accomplishments of this three-year Laboratory Directed Research and Development (LDRD) Exploratory Research Project (ERP) entitled ''X-ray Laser Propagation and Coherence: Diagnosing Fast-evolving, High-density Laser Plasmas Using X-ray Lasers,'' tracking code 93-ERP-075. The most significant accomplishment of this project is the demonstration of a new laser plasma diagnostic: a soft x-ray Mach-Zehnder interferometer using a neonlike yttrium x-ray laser at 155 angstrom as the probe source. Detailed comparisons of absolute two-dimensional electron density profiles obtained from soft x-ray laser interferograms and profiles obtained from radiation hydrodynamics codes, such as LASNEX, will allow us to validate and benchmark complex numerical models used to study the physics of laser-plasma interactions. Thus the development of soft x-ray interferometry technique provides a mechanism to probe the deficiencies of the numerical models and is an important tool for, the high-energy density physics and science-based stockpile stewardship programs. The authors have used the soft x-ray interferometer to study a number of high-density, fast evolving, laser-produced plasmas, such as the dynamics of exploding foils and colliding plasmas. They are pursuing the application of the soft x-ray interferometer to study ICF-relevant plasmas, such as capsules and hohlraums, on the Nova 10-beam facility. They have also studied the development of enhanced-coherence, shorter-pulse-duration, and high-brightness x-ray lasers. The utilization of improved x-ray laser sources can ultimately enable them to obtain three-dimensional holographic images of laser-produced plasmas

  2. Localization of the solar flare SF900610 in X-rays with the WATCH instrument of the GRANAT observatory

    DEFF Research Database (Denmark)

    Terekhov, O.V.; Kuzmin, A.G.; Shevchenko, A.V.

    2002-01-01

    -ray source do not coincide with the coordinates of the Ha-line flare. The X-ray source moved over the solar disk during the flare. This probably implies that, as the X-ray emission was generated, different parts of one loop or a system of magnetic loops dominated at different flare times.......During the solar flare of June 10, 1990, the WATCH instrument of the GRANAT space observatory obtained 110 localizations of the X-ray source in the X-ray range 8-20 keV. Its coordinates were measured with an accuracy of similar to2 arcmin at a 3sigma confidence level. The coordinates of the X...

  3. X-ray generation by femtosecond laser pulses and its application to soft X-ray imaging microscope

    International Nuclear Information System (INIS)

    Ikeda, Kenichi; Kotaki, Hideyuki; Nakajima, Kazuhisa

    2002-01-01

    We have developed laser-produced plasma X-ray sources using femtosecond laser pulses at 10Hz repetition rate in a table-top size in order to investigate basic mechanism of X-ray emission from laser-matter interactions and its application to a X-ray microscope. In a soft X-ray region over 5 nm wavelength, laser-plasma X-ray emission from a solid target achieved an intense flux of photons of the order of 1011 photons/rad per pulse with duration of a few 100 ps, which is intense enough to make a clear imaging in a short time exposure. As an application of laser-produced plasma X-ray source, we have developed a soft X-ray imaging microscope operating in the wavelength range around 14 nm. The microscope consists of a cylindrically ellipsoidal condenser mirror and a Schwarzshird objective mirror with highly-reflective multilayers. We report preliminary results of performance tests of the soft X-ray imaging microscope with a compact laser-produced plasma X-ray source

  4. Exotic x-ray emission from dense plasmas

    Czech Academy of Sciences Publication Activity Database

    Rosmej, F.B.; Dachicourt, R.; Deschaud, B.; Khaghani, D.; Dozières, M.; Šmíd, Michal; Renner, Oldřich

    2015-01-01

    Roč. 48, č. 22 (2015), s. 224005 ISSN 0953-4075 R&D Projects: GA MŠk ED1.1.00/02.0061 EU Projects: European Commission(XE) 284464 - LASERLAB-EUROPE Grant - others:ELI Beamlines(XE) CZ.1.05/1.1.00/02.0061; AVČR(CZ) M100101208 Institutional support: RVO:68378271 Keywords : hollow ions * x-ray spectroscopy * atomic physics Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.833, year: 2015

  5. Development of X-ray and ion diagnostic methods for plasma focus research

    International Nuclear Information System (INIS)

    Sadowski, M.

    1986-12-01

    A review of experimental methods used for investigation of X-rays and ion-beams emmited from plasma focus facilities is presented. The research program has been realized at the Institute for Nuclear Studies in Swierk and at the Institut fuer Plasmaforschung in Stuttgart, within the frames of an international co-operation. The studies on ion emission from different PF facilities are reviewed. The application of CN-films with Al-filters and of different ion-pinhole cameras is described. The use of a Thomson mass-spectrometer adopted for plasma studies is presented. The time-resolved measurements combined with a simultaneous mass- and energy-analysis of the ion beams are also described. The most important results of these studies are summarized. Particular attention is also paid to the studies of the X-ray emission. The use of stereoscopic sets of vacuum pinhole cameras with thin Be-filters is described. The application of X-ray pinhole cameras equipped with miniature scintillators for time-resolved measurements is also presented. The most important results of the X-ray emission studies are summarized. 35 refs., 12 figs. (author)

  6. Active Detectors for Plasma Soft X-Ray Detection at PALS

    Directory of Open Access Journals (Sweden)

    C. Granja

    2010-01-01

    Full Text Available This paper summarizes the work carried out for an experimental study of low-energy nuclear excitation by laser-produced plasma at the PALS Prague laser facility. We describe the adaptation and shielding of single-quantum active radiation detectors developed at IEAP CTU Prague to facilitate their operation inside the laser interaction chamber in the vicinity of the plasma target. The goal of this effort is direct real-time single-quantum detection of plasma soft X-ray radiation with energy above a few keV and subsequent identification of the decay of the excited nuclear states via low-energy gamma rays in a highly radiative environment with strong electromagnetic interference.

  7. The first X-ray imaging spectroscopy of quiescent solar active regions with NuSTAR

    DEFF Research Database (Denmark)

    Hannah, Iain G.; Grefenstette, Brian W.; Smith, David M.

    2016-01-01

    We present the first observations of quiescent active regions (ARs) using the Nuclear Spectroscopic Telescope Array (NuSTAR), a focusing hard X-ray telescope capable of studying faint solar emission from high-temperature and non-thermal sources. We analyze the first directly imaged and spectrally...... resolved X-rays above 2 keV from non-flaring ARs, observed near the west limb on 2014 November 1. The NuSTAR X-ray images match bright features seen in extreme ultraviolet and soft X-rays. The NuSTAR imaging spectroscopy is consistent with isothermal emission of temperatures 3.1-4.4 MK and emission...

  8. Picosecond Soft-X-ray studies of Dense Plasma Regimes Progress Report (April 1, 2006 - March 31, 2007)

    International Nuclear Information System (INIS)

    Rocca, Jorge; Marconi, Mario; Shlyaptsev, Vyacheslav; Dunn, James; Moon, Stephen; Nilsen, Joseph

    2007-01-01

    The goal of this project is to investigate and characterize high-density converging plasma configurations using new soft x-ray laser based interferometric techniques. The results are used to verify and validate multi-dimensional hydrodynamic codes in plasma regimes which densities and size exceed those that can be probed with optical laser beams. The dynamics of converging plasmas created by laser irradiation of half-hohlraum cylindrical cavities targets was probed using a compact 46.9 nm soft x-ray laser. The results were used for comparison with extensive simulations conducted with the multi-dimensional hydrodynamic code HYDRA. As part of this study we have also investigated plasma regimes in which the index of refraction of the plasmas can not be defined solely based on the contribution of free electron, as is usually assumed for multiply ionized plasmas. Our results demonstrate the existence of plasma regimes in which the contribution of bound electrons from ions dominates the refractive index at soft x-ray wavelengths. We are also working in extending plasma interferometry to the sub 10 nm wavelength range. In the process we are advancing soft x-ray laser plasma diagnostics techniques to allow the measurement of large-scale, high-density plasmas with picosecond temporal resolution and micrometer spatial resolution, laying the foundations for future advanced diagnostics at high energy density DOE facilities. Dense plasma diagnostics, soft x-ray laser interferometry, converging plasmas

  9. Very high resolution UV and x-ray spectroscopy and imagery of solar active regions. Final report

    International Nuclear Information System (INIS)

    Bruner, M.; Brown, W.A.; Haisch, B.M.

    1987-01-01

    A scientific investigation of the physics of the solar atmosphere, which uses the techniques of high resolution soft x-ray spectroscopy and high resolution UV imagery, is described. The experiments were conducted during a series of three sounding rocket flights. All three flights yielded excellent images in the UV range, showing unprecedented spatial resolution. The second flight recorded the x-ray spectrum of a solar flare, and the third that of an active region. A normal incidence multi-layer mirror was used during the third flight to make the first astronomical x-ray observations using this new technique

  10. Structural mechanics of the solar-A Soft X-ray Telescope

    Science.gov (United States)

    Jurcevich, B. K.; Bruner, M. E.; Gowen, K. F.

    1992-01-01

    The Soft X-ray Telescope (SXT) is one of four major instruments that constitute the payload of the NASA-Japanese mission YOHKOH (formerly known as Solar-A), scheduled to be launched in August, 1991. This paper describes the design of the SXT, the key system requirements, and the SXT optical and structural systems. Particular attention is given to the design considerations for stiffness and dimensional stability, temperature compensation, and moisture sensitivyty control. Consideration is also given to the X-ray mirror, the aspect telescope, the entrance filters, the mechanical structure design, the aft support plate and mount, the SXT finite element model, and other subsystems.

  11. X-ray Spectroscopy of Hot Dense Plasmas: Experimental Limits, Line Shifts and Field Effects

    International Nuclear Information System (INIS)

    Renner, Oldrich; Sauvan, Patrick; Dalimier, Elisabeth; Riconda, Caterina; Rosmej, Frank B.; Weber, Stefan; Nicolai, Philippe; Peyrusse, Olivier; Uschmann, Ingo; Hoefer, Sebastian; Kaempfer, Tino; Loetzsch, Robert; Zastrau, Ulf; Foerster, Eckhart; Oks, Eugene

    2008-01-01

    High-resolution x-ray spectroscopy is capable of providing complex information on environmental conditions in hot dense plasmas. Benefiting from application of modern spectroscopic methods, we report experiments aiming at identification of different phenomena occurring in laser-produced plasma. Fine features observed in broadened profiles of the emitted x-ray lines and their satellites are interpreted using theoretical models predicting spectra modification under diverse experimental situations.

  12. Influence of Xe and Kr impurities on x-ray yield from debris-free plasma x-ray sources with an Ar supersonic gas jet irradiated by femtosecond near-infrared-wavelength laser pulses

    Science.gov (United States)

    Kantsyrev, V. L.; Schultz, K. A.; Shlyaptseva, V. V.; Petrov, G. M.; Safronova, A. S.; Petkov, E. E.; Moschella, J. J.; Shrestha, I.; Cline, W.; Wiewior, P.; Chalyy, O.

    2016-11-01

    Many aspects of physical phenomena occurring when an intense laser pulse with subpicosecond duration and an intensity of 1018-1019W /cm2 heats an underdense plasma in a supersonic clustered gas jet are studied to determine the relative contribution of thermal and nonthermal processes to soft- and hard-x-ray emission from debris-free plasmas. Experiments were performed at the University of Nevada, Reno (UNR) Leopard laser operated with a 15-J, 350-fs pulse and different pulse contrasts (107 or 105). The supersonic linear (elongated) nozzle generated Xe cluster-monomer gas jets as well as jets with Kr-Ar or Xe-Kr-Ar mixtures with densities of 1018-1019cm-3 . Prior to laser heating experiments, all jets were probed with optical interferometry and Rayleigh scattering to measure jet density and cluster distribution parameters. The supersonic linear jet provides the capability to study the anisotropy of x-ray yield from laser plasma and also laser beam self-focusing in plasma, which leads to efficient x-ray generation. Plasma diagnostics included x-ray diodes, pinhole cameras, and spectrometers. Jet signatures of x-ray emission from pure Xe gas, as well as from a mixture with Ar and Kr, was found to be very different. The most intense x-ray emission in the 1-9 KeV spectral region was observed from gas mixtures rather than pure Xe. Also, this x-ray emission was strongly anisotropic with respect to the direction of laser beam polarization. Non-local thermodynamic equilibrium (Non-LTE) models have been implemented to analyze the x-ray spectra to determine the plasma temperature and election density. Evidence of electron beam generation in the supersonic jet plasma was found. The influence of the subpicosecond laser pulse contrast (a ratio between the laser peak intensity and pedestal pulse intensity) on the jets' x-ray emission characteristics is discussed. Surprisingly, it was found that the x-ray yield was not sensitive to the prepulse contrast ratio.

  13. Maximum material thickness for extreme ultra-violet and X-ray backlighter probing of dense plasma

    International Nuclear Information System (INIS)

    Huang, H.; Tallents, G.J.

    2008-01-01

    Extreme ultra-violet (EUV) lasers, X-ray lasers and other backlighter sources can be used to probe high-energy density materials if their brightness can overcome self-emission from the material. We investigate the maximum plasma thickness of aluminum, silicon and iron that can be probed with EUV or X-ray photons of energy 89-1243 eV before self-emission from the plasma overwhelms the backlighter output. For a uniform plasma, backlighter transmission decreases exponentially with increasing thickness of the material following Beer's law at a rate dependent on the plasma opacity. We evaluate the plasma opacity with the Los Alamos TOPS opacity data. The self-emission is assumed to be either that of a black body to arise from a plasma in LTE or to only consist of free-free and free-bound emission. It is shown that at higher plasma temperature (≥40 eV), EUV radiation (e.g. photon energy=89 eV) can probe a greater thickness of plasma than X-ray radiation (e.g. photon energy=1243 eV)

  14. The Relation Between Magnetic Fields and X-ray Emission for Solar Microflares and Active Regions

    Science.gov (United States)

    Kirichenko, A. S.; Bogachev, S. A.

    2017-09-01

    We present the result of a comparison between magnetic field parameters and the intensity of X-ray emission for solar microflares with Geosynchronous Operational Environmental Satellites (GOES) classes from A0.02 to B5.1. For our study, we used the monochromatic MgXII Imaging Spectroheliometer (MISH), the Full-disk EUV Telescope (FET), and the Solar PHotometer in X-rays (SphinX) instruments onboard the Complex Orbital Observations Near-Earth of Activity of the Sun-Photon CORONAS- Photon spacecraft because of their high sensitivity in soft X-rays. The peak flare flux (PFF) for solar microflares was found to depend on the strength of the magnetic field and on the total unsigned magnetic flux as a power-law function. In the spectral range 2.8 - 36.6 Å, which shows very little increase related to microflares, the power-law index of the relation between the X-ray flux and magnetic flux for active regions is 1.48 ±0.86, which is close to the value obtained previously by Pevtsov et al. ( Astrophys. J. 598, 1387, 2003) for different types of solar and stellar objects. In the spectral range 1 - 8 Å, the power-law indices for PFF(B) and PFF(Φ) for microflares are 3.87 ±2.16 and 3 ±1.6, respectively. We also make suggestions on the heating mechanisms in active regions and microflares under the assumption of loops with constant pressure and heating using the Rosner-Tucker-Vaiana scaling laws.

  15. Scaling Laws of Nitrogen Soft X-Ray Yields from 1 to 200 kJ Plasma Focus

    International Nuclear Information System (INIS)

    Akel, M.; Lee, S.

    2013-01-01

    Numerical experiments are carried out systematically to determine the nitrogen soft x-ray yield for optimized nitrogen plasma focus with storage energy E 0 from 1 kJ to 200 kJ. Scaling laws on nitrogen soft x-ray yield, in terms of storage energies E 0 , peak discharge current I p eak and focus pinch current I p inch were found. It was found that the nitrogen x-ray yields scales on average with y s xr, N= 1.93xE o 1 .21 J (E 0 in kJ) with the scaling showing gradual deterioration as E 0 rises over the range. A more robust scaling is y s xr = 8x10 - 8I 0 3.38 p inch . The optimum nitrogen soft x-ray yield emitted from plasma focus is found to be about 1 kJ for storage energy of 200 kJ. This indicates that nitrogen plasma focus is a good water-window soft x-ray source when properly designed. (author)

  16. Working gas effects on the X-ray emission of a plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Cengher, M; Presura, R; Zoita, V [Inst. of Physics and Technology of Radiation Devices, Bucharest (Romania)

    1997-12-31

    Experiments on the plasma focus device IPF-2/20 operating with argon, neon and mixtures of argon with deuterium were performed and some X-ray emission parameters measured. The time evolution of the X-ray emission and dependence of the X-ray yield on the working gas composition was analyzed. The softer X radiation was measured with time resolution in the energy bands from 4 to 40 keV, and the hard X-rays for energies above 200 keV. In deuterium-argon mixtures the soft X-ray yield increases both with pressure (for the same ratio of argon) and with the quantity of argon added to deuterium at the same total pressure. For argon or neon the hard X-ray yield is lower than for deuterium-heavy gas mixtures. The softer X-ray yield decreases with pressure both for neon and for argon. (author). 4 figs., 5 refs.

  17. Optically-ionized plasma recombination x-ray lasers

    International Nuclear Information System (INIS)

    Amendt, P.; Eder, D.C.; Wilks, S.C.; Dunning, M.J.; Keane, C.J.

    1991-01-01

    Design studies for recombination x-ray lasers based on plasmas ionized by high intensity, short pulse optical lasers are presented. Transient lasing on n = 3 to n = 2 transitions in Lithium-like Neon allows for moderately short wavelengths (≤ 100 angstrom) without requiring ionizing intensities associated with relativistic electron quiver energies. The electron energy distribution following the ionizing pulse affects directly the predicted gains for this resonance transition. Efficiencies of 10 -6 or greater are found for plasma temperatures in the vicinity of 40 eV. Simulation studies of parametric heating phenomena relating to stimulated Raman and Compton scattering are presented. For electron densities less than about 2.5 x 10 20 cm -3 and peak driver intensity of 2 x 10 17 W/cm 2 at 0.25 μm with pulse length of 100 fsec, the amount of electron heating is found to be marginally significant. For Lithium-like Aluminum, the required relativistic ionizing intensity gives excessive electron heating and reduced efficiency, thereby rendering this scheme impractical for generating shorter wavelength lasing (≤ 50 angstrom) in the transient case. Following the transient lasing phase, a slow hydrodynamic expansion into the surrounding cool plasma is accompanied by quasi-static gain on the n = 4 to n = 3 transition in Lithium-like Neon. Parametric heating effects on gain optimization in this regime are also discussed. 18 refs., 6 figs

  18. Parametric study of x-ray pre-ionizer with plasma cathode

    International Nuclear Information System (INIS)

    Bollanti, S.; Di Lazzaro, P.; Flora, F.; Giordano, G.; Letardi, T.; Schina, G.; Zheng, C.

    1993-01-01

    The construction characteristics and the performance of an x-ray diode working at 200 Hz are described. The temporal behavior of both the plasma cathode emission and the diode discharge was studied, including the measurements of vacuum effects on the repetition rate and lifetime capability, pre-ionization versus electrical features, and ionization density versus dosage. This simple and low-cost x-ray diode was used to uniformly pre-ionize a half-liter XeCl laser, delivering an output laser energy of 800 mJ/shot at a 100-Hz repetition rate

  19. A new sounding rocket payload for solar plasma studies

    International Nuclear Information System (INIS)

    Bruner, M.E.; Brown, W.A.; Appert, K.L.

    1989-01-01

    A sounding rocket payload developed for studies of high-temperature plasmas associated with solar active regions and flares is described. The payload instruments will record both spectra and images in the UV, EUV, and soft X-ray regions of the spectrum. The instruments, including the Dual Range Spectrograph, the Flat Field Soft X-ray Spectrograph, the Normal Incidence Soft X-ray Imager, the UV Filtergraph, and the H-alpha Imaging system, are described. Attention is also given to the new structural system of the payload, based on a large optical table suspended within the payload cavity, which will support the optical elements in their correct positions and orientations and will maintain these alignments throughout the rocket launch environment. 8 refs

  20. Time-resolved X-ray diffraction with accelerator- and laser-plasma-based X-ray sources

    International Nuclear Information System (INIS)

    Nicoul, Matthieu

    2010-01-01

    Femtosecond X-ray pulses are a powerful tool to investigate atomic motions triggered by femtosecond pump pulses. This thesis is dedicated to the production of such pulses and their use in optical pump - X-ray probe measurement. This thesis describes the laser-plasma-based sources available at the University of Duisburg-Essen. Part of it consists of the description of the design, built-up and characterization of a new ''modular'' X-ray source dedicated to optimize the X-ray flux onto the sample under investigation. The acoustic wave generation in femtosecond optically excited semiconductor (gallium arsenide) and metal (gold) was performed using the sources of the University of Duisburg-Essen. The physical answer of the material was modeled by a simple strain model for the semiconductor, pressure model for the metal, in order to gain information on the interplay of the electronic and thermal pressures rising after excitation. Whereas no reliable information could be obtain in gallium arsenide (principally due to the use of a bulk), the model for gold achieved very good agreement, providing useful information. The relaxation time of the electron to lattice energy was found to be (5.0±0.3) ps, and the ratio of the Grueneisen parameters was found to be γ e / γ i = (0.5±0.1). This thesis also describes the Sub-Picosecond Pulse Source (SPPS) which existed at the (formally) Stanford Linear Accelerator Center, an accelerator-based X-ray source, and two measurements performed with it. The first one is the detailed investigation of the phonon softening of the A 1g mode launch in bismuth upon fluence excitation. Detailed information concerning the new equilibrium position and phonon frequency were obtained over extended laser pump fluences. The second measurement concerned the study of the liquid phase dynamics in a newly formed liquid phase following ultrafast melting in indium antimonide. The formation of the liquid phase and its development for excitations close to the

  1. Time-resolved X-ray diffraction with accelerator- and laser-plasma-based X-ray sources

    Energy Technology Data Exchange (ETDEWEB)

    Nicoul, Matthieu

    2010-09-01

    Femtosecond X-ray pulses are a powerful tool to investigate atomic motions triggered by femtosecond pump pulses. This thesis is dedicated to the production of such pulses and their use in optical pump - X-ray probe measurement. This thesis describes the laser-plasma-based sources available at the University of Duisburg-Essen. Part of it consists of the description of the design, built-up and characterization of a new ''modular'' X-ray source dedicated to optimize the X-ray flux onto the sample under investigation. The acoustic wave generation in femtosecond optically excited semiconductor (gallium arsenide) and metal (gold) was performed using the sources of the University of Duisburg-Essen. The physical answer of the material was modeled by a simple strain model for the semiconductor, pressure model for the metal, in order to gain information on the interplay of the electronic and thermal pressures rising after excitation. Whereas no reliable information could be obtain in gallium arsenide (principally due to the use of a bulk), the model for gold achieved very good agreement, providing useful information. The relaxation time of the electron to lattice energy was found to be (5.0{+-}0.3) ps, and the ratio of the Grueneisen parameters was found to be {gamma}{sub e} / {gamma}{sub i} = (0.5{+-}0.1). This thesis also describes the Sub-Picosecond Pulse Source (SPPS) which existed at the (formally) Stanford Linear Accelerator Center, an accelerator-based X-ray source, and two measurements performed with it. The first one is the detailed investigation of the phonon softening of the A{sub 1g} mode launch in bismuth upon fluence excitation. Detailed information concerning the new equilibrium position and phonon frequency were obtained over extended laser pump fluences. The second measurement concerned the study of the liquid phase dynamics in a newly formed liquid phase following ultrafast melting in indium antimonide. The formation of the liquid phase

  2. Highly ionized copper contribution to the soft X-ray emission in a plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Zoita, V; Patran, A [Inst. of Physics and Technology of Radiation Devices, Bucharest (Romania); Larour, J [Ecole Polytechnique, Palaiseau (France). Lab. de Physique des Milieux Ionises

    1997-12-31

    In order to discriminate between the contributions of the gas plasma and of the anode (solid or plasma) to the soft X-ray emission in a plasma focus device, a series of experiments was carried out using the following combinations of experimental conditions: various gases, different absorption filters and viewing different regions in front of the centre electrode. The experiments were performed on the IPF-2/20 plasma focus device using the following working gases: helium, neon and helium-argon mixtures. The diagnostics used: magnetic probe for current derivative, PIN diode for the minimum pinch radius detection, PIN diodes for the soft X-ray emission, scintillator-photomultiplier detector for the hard X-ray emission. From the analysis of the various diagnostics data recorded with very good time correlation, it followed that the soft K-ray signals had a strong contribution from optical transitions of the highly ionised Cu (Cu XX to XXII) emitting in the range 0.8-1.3 nm. (author). 7 figs., 9 refs.

  3. Design of the detector to observe the energetic charged particles: a part of the solar X-ray spectrophotometer ChemiX onboard Interhelio-Probe mission

    Science.gov (United States)

    Dudnik, Oleksiy; Sylwester, Janusz; Kowalinski, Miroslaw; Bakala, Jaroslaw; Siarkowski, Marek; Evgen Kurbatov, mgr..

    2016-07-01

    Cosmic particle radiation may damages payload's electronics, optics, and sensors during of long-term scientific space mission especially the interplanetary ones. That is why it's extremely important to prevent failures of digital electronics, CCDs, semiconductor detectors at the times of passing through regions of enhanced charged particle fluxes. Well developed models of the Earth's radiation belts allow to predict and to protect sensitive equipment against disastrous influence of radiation due to energetic particle contained in the Van Allen belts. In the contrary interplanetary probes flying far away from our planet undergoes passages through clouds of plasma and solar cosmic rays not predictable by present models. Especially these concerns missions planned for non-ecliptic orbits. The practical approach to protect sensitive modules may be to measure the in situ particle fluxes with high time resolution and generation of alarm flags, which will switch off sensitive units of particular scientific equipment. The ChemiX (Chemical composition in X-rays) instrument is being developed by the Solar Physics Division of Polish Space Research Centre for the Interhelio-Probe interplanetary mission. Charged particle bursts can badly affect the regular measurements of X-ray spectra of solar origin. In order to detect presence of these enhanced particle fluxes the Background Particle Monitor (BPM) was developed constituting now a vital part of ChemiX. The BPM measurements of particle fluxes will assist to determine level of X-ray spectra contamination. Simultaneously BPM will measure the energy spectra of ambient particles. We present overall structure, design, technical and a scientific characteristic of BPM, particle sorts, and energy ranges to be registered. We describe nearly autonomous modular structure of BPM consisting of detector head, analogue and digital electronics modules, and of module of secondary power supply [1-3]. Detector head consists of three

  4. Efficient soft x-ray generation in short wavelength laser produced plasmas

    International Nuclear Information System (INIS)

    Mochizuki, T.; Yamanaka, C.

    1987-01-01

    Intense x-ray generation in 1.053, 0.53, 0.26 μm laser-produced plasma has been investigated in the photon energy range of 0.1 to 3keV. The x-ray spectrum is found to have several humps which move to the higher energy side as the atomic number of the target increases. This atomic dependence is explained by a semi-Moseley's law and allows us to predict a target material most suitable for generating the photons of desired energies. Conversion efficiencies of 1.5 -- 3keV x-rays are obtained also as a function of laser wavelength at the intensity of 10/sup 13/W/cm/sup 2/. The conversion efficiency of keV x rays has been enhanced by a factor of 2 -- 3 with a controlled prepulse laser. From the semi-Moseley's law we find that cryogenic targets using either Xe or Kr in a liquid or solid phase may be most useful for a number of applications because they radiate 1 -- 3 keV x rays efficiently and never deposit on the x-ray optical components and the objects to be exposed

  5. Sudden f/sub min/ enhancements and sudden cosmic noise absorptions associated with solar X-ray flares

    Energy Technology Data Exchange (ETDEWEB)

    Sato, T [Hyogo Coll. of Medicine, Hyogo (Japan). Dept. of Physics

    1975-01-01

    Sudden fsub(min) enhancements (SFsub(m)E's) and sudden cosmic noise absorptions (SCNA's) associated with increments of X-ray fluxes during solar flares are studied on the basis of X-ray flux data measured by SOLRAD 9 and 10 satellites. Some statistical analyses on SFsub(m)E's observed at five observatories in Japan, corresponding to increased X-ray fluxes in the 1-8 A band are made for 50 solar flare events during the period January 1972 to December 1973, and value of fsub(min) is expressed as functions of cos x(x; solar zenith angle) and 1-8 A band X-ray flux. Similar study is also made for SCNA's observed by 30 MHz riometer at Hiraiso for 15 great solar flare events during the same period, together with 27.6 MHz riometer data reported by Schwentek (1973) and 18 MHz data published by Deshpande and Mitra (1972b). It is found that fsub(min) value (MHz) and SCNA value (L, dB) of a radio wave with frequency f(MHz) are related to X-ray flux (F/sub 0/, erg cm/sup -2/ sec/sup -1/) in the 1-8 A band and to cos x, by following approximate expressions, fsub(min)(MHz)=10F/sub 0/sup(1/4) cossup(1/2) x, and L(dB)=4.37x10/sup 3/f/sup -2/F/sub 0/sup(1/2) cos x, respectively. Blackout seems to occur for F/sub 0/ values causing fsub(min)'s greater than about 5 MHz. It is shown that these expressions can be derived from a brief theoretical calculation of radio wave absorption in the lower ionosphere. Also it is suggested that threshold X-ray fluxes in the 1-8 A band which may produce a minimum SFsub(m)E (2 MHz), blackout and minimum SCNA (0.27-0.36 dB for 30 MHz noise) are 1.6x10/sup -3/, 6.2x10/sup -2/ and (3-8) x 10/sup -3/ erg cm/sup -2/ sec/sup -1/, respectively, for cos x=1.

  6. THE ROLE OF KELVIN–HELMHOLTZ INSTABILITY FOR PRODUCING LOOP-TOP HARD X-RAY SOURCES IN SOLAR FLARES

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Xia; Yuan, Ding; Xia, Chun; Doorsselaere, Tom Van; Keppens, Rony [Centre for Mathematical Plasma Astrophysics, Department of Mathematics, KU Leuven, Celestijnenlaan 200B, 3001 Leuven (Belgium)

    2016-12-10

    We propose a model for the formation of loop-top hard X-ray (HXR) sources in solar flares through the inverse Compton mechanism, scattering the surrounding soft X-ray (SXR) photons to higher energy HXR photons. We simulate the consequences of a flare-driven energy deposit in the upper chromosphere in the impulsive phase of single loop flares. The consequent chromosphere evaporation flows from both footpoints reach speeds up to hundreds of kilometers per second, and we demonstrate how this triggers Kelvin–Helmholtz instability (KHI) in the loop top, under mildly asymmetric conditions, or more toward the loop flank for strongly asymmetric cases. The KHI vortices further fragment the magnetic topology into multiple magnetic islands and current sheets, and the hot plasma within leads to a bright loop-top SXR source region. We argue that the magnetohydrodynamic turbulence that appears at the loop apex could be an efficient accelerator of non-thermal particles, which the island structures can trap at the loop-top. These accelerated non-thermal particles can upscatter the surrounding thermal SXR photons emitted by the extremely hot evaporated plasma to HXR photons.

  7. Picosecond x-ray streak camera studies

    International Nuclear Information System (INIS)

    Kasyanov, Yu.S.; Malyutin, A.A.; Richardson, M.C.; Chevokin, V.K.

    1975-01-01

    Some initial results of direct measurement of picosecond x-ray emission from laser-produced plasmas are presented. A PIM-UMI 93 image converter tube, incorporating an x-ray sensitive photocathode, linear deflection, and three stages of image amplification was used to analyse the x-ray radiation emanating from plasmas produced from solid Ti targets by single high-intensity picosecond laser pulses. From such plasmas, the x-ray emission typically persisted for times of 60psec. However, it is shown that this detection system should be capable of resolving x-ray phenomena of much shorter duration. (author)

  8. Deducing Electron Properties from Hard X-Ray Observations

    Science.gov (United States)

    Kontar, E. P.; Brown, J. C.; Emslie, A. G.; Hajdas, W.; Holman, G. D.; Hurford, G. J.; Kasparova, J.; Mallik, P. C. V.; Massone, A. M.; McConnell, M. L.; hide

    2011-01-01

    X-radiation from energetic electrons is the prime diagnostic of flare-accelerated electrons. The observed X-ray flux (and polarization state) is fundamentally a convolution of the cross-section for the hard X-ray emission process(es) in question with the electron distribution function, which is in turn a function of energy, direction, spatial location and time. To address the problems of particle propagation and acceleration one needs to infer as much information as possible on this electron distribution function, through a deconvolution of this fundamental relationship. This review presents recent progress toward this goal using spectroscopic, imaging and polarization measurements, primarily from the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI). Previous conclusions regarding the energy, angular (pitch angle) and spatial distributions of energetic electrons in solar flares are critically reviewed. We discuss the role and the observational evidence of several radiation processes: free-free electron-ion, free-free electron-electron, free-bound electron-ion, photoelectric absorption and Compton backscatter (albedo), using both spectroscopic and imaging techniques. This unprecedented quality of data allows for the first time inference of the angular distributions of the X-ray-emitting electrons and improved model-independent inference of electron energy spectra and emission measures of thermal plasma. Moreover, imaging spectroscopy has revealed hitherto unknown details of solar flare morphology and detailed spectroscopy of coronal, footpoint and extended sources in flaring regions. Additional attempts to measure hard X-ray polarization were not sufficient to put constraints on the degree of anisotropy of electrons, but point to the importance of obtaining good quality polarization data in the future.

  9. Use of a solar panel as a directionally sensitive large-area radiation monitor for direct and scattered x-rays and gamma-rays.

    Science.gov (United States)

    Abdul-Majid, S

    1987-01-01

    The characteristics of a 25.4 X 91 cm solar cell panel used as an x-ray and gamma-ray radiation monitor are presented. Applications for monitoring the primary x-ray beam are described at different values of operating currents and voltages as well as for directional dependence of scattered radiation. Other applications in gamma-ray radiography are also given. The detector showed linear response to both x-ray and gamma-ray exposures. The equipment is rigid, easy to use, relatively inexpensive and requires no power supply or any complex electronic equipment.

  10. Capillary-discharge sodium plasma for pulsed-power X-ray laser experiments

    International Nuclear Information System (INIS)

    Young, F.C.; Commisso, R.J.; Cooperstein, G.

    1986-01-01

    A capillary discharge plasma is being studied as a source of sodium plasma for Na/Ne x-ray laser experiments. The objective is to develop an intense x-ray pump of He-α emission from Na for matched-line photopumping of Ne. A uniform Na-bearing plasma (≅2-cm dia and ≅4-cm long) is to be injected into the anode-cathode gap of the Gamble II pulsed-power generator and imploded by MA-level currents to produce the intense sodium K-line radiation. Implosions of neon gas puffs have produced up to 50 GW of 0.92-keV He-α line emission, and similar x-ray power is expected from sodium implosions. Plasma from the capillary is produced by discharging current through an evacuated small hole in a plastic dielectric (≤ 3-mm dia and 1 to 2.5-cm long). A Na-bearing plasma is generated by forming the hole in NaF. Discharges of 30-kA (60-kA) peak current and 2-μs (2.6-μs) period are provided by a 0.6-μF (1.8-μF) capacitor bank charged to 25 kV. Diagnostics to evaluate plasma characteristics include witness plates, Faraday cups, photodiodes, open-shutter photographs, framing images, and visible light and near UV spectrographs. This plasma source emits visible light for 5-10 μs over a region extending - 1.5 cm from the capillary. Emission is more intense for capillary dia ≤ 0.8 mm. Spectroscopic measurements indicate that both positive ions and neutrals are present, including neutral Na from NaF capillaries. Velocities of≅2 cm/μs are deduced from Faraday cup measurements. For a 0.3-mm dia plastic capillary and 30-kA discharge current, ≅100 μg of capillary material is removed, which corresponds to≅10 μg/cm in the plasma

  11. Deka-keV X-ray observations of solar bursts with WATCH/GRANAT: frequency distributions of burst parameters

    DEFF Research Database (Denmark)

    Crosby, N.; Vilmer, N.; Lund, Niels

    1998-01-01

    be observed as low as 10 keV. A statistical study is performed on the total WATCH solar database and frequency distributions are built on measured X-ray flare parameters. It is also investigated how the properties of these frequency distributions behave when subgroups of events defined by different ranges......Solar flare observations in the deka-keV range are performed by the WATCH experiment on board the GRANAT satellite. The WATCH experiment is presented, including the energy calibration as applied in the present work. The creation of the solar burst catalogue covering two years of observation...... is described and some examples of solar observations are given. The estimated energy releases in the flares presented here are found to extend below the range of hard X-ray flares which were previously studied by ISEE-3 and HXRBS/SMM detectors. The X-ray emitting component cannot be exclusively explained...

  12. High resolution X-ray spectroscopy of laser generated plasmas

    International Nuclear Information System (INIS)

    Faenov, A.Ya.; Skobelev, I.Yu.; Rosmej, F.B.

    1999-01-01

    The application of recently developed spectroscopic instruments in laser produced plasmas with simultaneous high spectral and spatial resolution combined with high luminosity discovered new types of X-ray spectra. These new types are characterised by the disappearance of the resonance lines and the strong emission of dielectronic satellite spectra. Several types of transitions of highly charged ions are discovered which are unknown from usual sources employed in atomic physics. New theoretical models are developed and successfully applied for the interpretation and for plasma diagnostics. (orig.)

  13. High resolution X-ray spectroscopy of laser generated plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Faenov, A.Ya.; Skobelev, I.Yu. [Multicharged Ions Spectra Data Center of VNIIFTRI, Mendeleevo (Russian Federation); Rosmej, F.B. [Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik

    1999-11-01

    The application of recently developed spectroscopic instruments in laser produced plasmas with simultaneous high spectral and spatial resolution combined with high luminosity discovered new types of X-ray spectra. These new types are characterised by the disappearance of the resonance lines and the strong emission of dielectronic satellite spectra. Several types of transitions of highly charged ions are discovered which are unknown from usual sources employed in atomic physics. New theoretical models are developed and successfully applied for the interpretation and for plasma diagnostics. (orig.) 28 refs.

  14. Hydrodynamic evolution of plasma waveguides for soft-x-ray amplifiers

    Science.gov (United States)

    Oliva, Eduardo; Depresseux, Adrien; Cotelo, Manuel; Lifschitz, Agustín; Tissandier, Fabien; Gautier, Julien; Maynard, Gilles; Velarde, Pedro; Sebban, Stéphane

    2018-02-01

    High-density, collisionally pumped plasma-based soft-x-ray lasers have recently delivered hundreds of femtosecond pulses, breaking the longstanding barrier of one picosecond. To pump these amplifiers an intense infrared pulse must propagate focused throughout all the length of the amplifier, which spans several Rayleigh lengths. However, strong nonlinear effects hinder the propagation of the laser beam. The use of a plasma waveguide allows us to overcome these drawbacks provided the hydrodynamic processes that dominate the creation and posterior evolution of the waveguide are controlled and optimized. In this paper we present experimental measurements of the radial density profile and transmittance of such waveguide, and we compare them with numerical calculations using hydrodynamic and particle-in-cell codes. Controlling the properties (electron density value and radial gradient) of the waveguide with the help of numerical codes promises the delivery of ultrashort (tens of femtoseconds), coherent soft-x-ray pulses.

  15. Hot and dense plasma probing by soft X-ray lasers

    Czech Academy of Sciences Publication Activity Database

    Krůs, Miroslav; Kozlová, Michaela; Nejdl, Jaroslav; Rus, B.

    2018-01-01

    Roč. 13, č. 1 (2018), č. článku C01004. ISSN 1748-0221. [International Symposium on Laser-Aided Plasma Diagnostics/18./. Prague, 24.09.2017-28.09.2017] R&D Projects: GA MŠk LM2010014; GA MŠk(CZ) LM2015083 Institutional support: RVO:61389021 Keywords : Plasma diagnostics - interferometry * spectroscopy and imaging * Plasma diagnostics - probes * Plasma generation (laser-produced, RF, x ray-produced) Subject RIV: BH - Optics, Masers, Lasers OBOR OECD: 2.11 Other engineering and technologies Impact factor: 1.220, year: 2016 http://iopscience.iop.org/article/10.1088/1748-0221/13/01/C01004

  16. High resolution time- and 2-dimensional space-resolved x-ray imaging of plasmas at NOVA

    International Nuclear Information System (INIS)

    Landen, O.L.

    1992-01-01

    A streaked multiple pinhole camera technique, first used by P. Choi et al. to record time- and 2-D space-resolved soft X-ray images of plasma pinches, has been implemented on laser plasmas at NOVA. The instrument is particularly useful for time-resolved imaging of small sources ( 2.5 key imaging, complementing the existing 1--3 key streaked X-ray microscope capabilities at NOVA

  17. The application of photoconductive detectors to the measurement of x-ray production in laser produced plasmas

    International Nuclear Information System (INIS)

    Kania, D.R.; Bell, P.; Trebes, J.

    1987-08-01

    Photoconductive detectors (PCDs) offer an attractive alternative for the measurement of pulsed x-rays from laser produced plasmas. These devices are fast (FWHM ∼100 ps), sensitive and simple to use. We have used InP, GaAs, and Type IIa diamond as PCDs to measure x-rays emission from 100 eV to 100 keV. Specifically, we have used these detectors to measure total radiation yields, corona temperatures, and hot electron generated x-rays from laser produced plasmas. 5 refs., 4 figs

  18. High-speed image converter x-ray studies

    International Nuclear Information System (INIS)

    Bryukhnevitch, G.I.; Kas'yanov, Yu.S.; Korobkin, V.V.; Prokhorov, A.M.; Stepanov, B.M.; Chevokin, V.K.; Schelev, M.Ya.

    1975-01-01

    Two X-ray high-speed image-converter cameras (ICC) have been developed. In the first one a soft X-ray radiation is converted into visible light with the aid of a 0.5ns response time, plastic scintillator. The second camera incorporates a photocathode which is sensitive to visible and X-ray radiation. Its calculated temporal resolution approaches 5 to 7ps. Both developed cameras were employed for studies of X-ray radiation emitted by laser plasma. For the smooth nanosecond excited laser pulses, a noticeable amplitude modulation was recorded in all laser pulses reflected by plasma as well as in each third pulse of X-ray plasma radiation. It was also observed that the duration of X-ray plasma radiation is 20 to 40% shorter than that of the incident nanosecond laser pulses and this duration being 3 to 6 times longer than that of the picosecond irradiating pulses. The half-width of the recorded X-ray plasma pulses was 30 to 60ps. (author)

  19. Electron density measurement of a colliding plasma using soft x-ray laser interferometry

    International Nuclear Information System (INIS)

    Wan, A.S.; Back, C.A.; Barbee, T.W.Jr.; Cauble, R.; Celliers, P.; DaSilva, L.B.; Glenzer, S.; Moreno, J.C.; Rambo, P.W.; Stone, G.F.; Trebes, J.E.; Weber, F.

    1996-05-01

    The understanding of the collision and subsequent interaction of counter-streaming high-density plasmas is important for the design of indirectly-driven inertial confinement fusion (ICF) hohlraums. We have employed a soft x-ray Mach-Zehnder interferometer, using a Ne- like Y x-ray laser at 155 angstrom as the probe source, to study interpenetration and stagnation of two colliding plasmas. We observed a peaked density profile at the symmetry axis with a wide stagnation region with width of order 100 μm. We compare the measured density profile with density profiles calculated by the radiation hydrodynamic code LASNEX and a multi-specie fluid code which allows for interpenetration. The measured density profile falls in between the calculated profiles using collisionless and fluid approximations. By using different target materials and irradiation configurations, we can vary the collisionality of the plasma. We hope to use the soft x-ray laser interferometry as a mechanism to validate and benchmark our numerical codes used for the design and analysis of high-energy- density physics experiments

  20. Analysis of solar blocker through portable X-ray fluorescence

    International Nuclear Information System (INIS)

    Ferreira, Diego de Dio; Melquiades, Fabio Luiz; Appoloni, Carlos Roberto; Lopes, Fabio; Lonni, Audrey Stinghen G.; Oliveira, Frederico Minardi de; Duarte, Jose C.

    2009-01-01

    This paper estimates the concentration of TiO 2 by Energy Dispersion X-ray fluorescence (EDXRF) viewing t obtain the FPS due to the physical barrier in the composition of solar blockers, and identifies possible present metals in the samples. A portable EDXRF equipment was used and 27 commercial of different brands and solar protection factors were analysed. Also, three formulations (A, B and C) were prepared and measured estimated in FPS-30 using 5% or TiO 2 . The quantification was performed through calibration curves with 1% to 30% standards of TiO 2 . As result, it was possible to determine the contribution to physical protection in the FPS, associated to the Ti concentration present in some solar blocker samples available in the market. Also, it was possible to detect the presence of various metals in solar protectors, such as Fe, Zn, Br and Sr, and identify chemical elements which were not mentioned and their formulation as well

  1. Characteristics of an intrinsic germanium detector for measurement of soft x-rays from high-temperature plasmas

    International Nuclear Information System (INIS)

    Kumagai, Katsuaki; Matoba, Tohru; Funahashi, Akimasa; Kawakami, Tomohide

    1976-09-01

    An intrinsic germanium (Ge(I)) detector has been prepared for measurement of soft X-ray spectra from high-temperature tokamak plasmas. Its characteristics of photo-peak efficiency, escape-peak and Compton scattering were calibrated with standard radioisotopes and soft X-rays from the JFT-2a plasma, and compared with those of a lithium-drifted silicon (Si(Li)) detector. Features of the Ge(I) detector are as follows: (i) high detection efficiency in the high energy range, (ii) wide energy range for measurement of soft X-ray spectra, and (iii) low Compton scattering effect in measurement of continuous spectra. Its dead-layer depth is about 0.06μm, and the minimum detectable energies in the Ge(I) detector are similar to those in the Si(Li) detector. The Ge(I) detector is effective for measuring soft X-ray spectra from high-temperature tokamak plasmas. (auth.)

  2. Improving Soft X-Ray Spectral Irradiance Models for Use Throughout the Solar System

    Science.gov (United States)

    Eparvier, F. G.; Thiemann, E.; Woods, T. N.

    2017-12-01

    Understanding the effects of solar variability on planetary atmospheres has been hindered by the lack of accurate models and measurements of the soft x-ray (SXR) spectral irradiance (0-6 nm). Most measurements of the SXR have been broadband and are difficult to interpret due to changing spectral distribution under the pass band of the instruments. Models that use reference spectra for quiet sun, active region, and flaring contributions to irradiance have been made, but with limited success. The recent Miniature X-ray Solar Spectrometer (MinXSS) CubeSat made spectral measurements in the 0.04 - 3 nm range from June 2016 to May 2017, observing the Sun at many different levels of activity. In addition, the Solar Dynamics Observatory (SDO) EUV Variability Experiment (EVE) has observed the Sun since May 2010, in both broad bands (including a band at 0-7 nm) and spectrally resolved (6-105 nm at 0.1 nm resolution). We will present an improved model of the SXR based on new reference spectra from MinXSS and SDO-EVE. The non-flaring portion of the model is driven by broadband SXR measurements for determining activity level and relative contributions of quiet and active sun. Flares are modeled using flare temperatures from the GOES X-Ray Sensors. The improved SXR model can be driven by any sensors that provide a measure of activity level and flare temperature from any vantage point in the solar system. As an example, a version of the model is using the broadband solar irradiance measurements from the MAVEN EUV Monitor at Mars will be presented.

  3. Characterizing Hohlraum Plasma Conditions at the National Ignition Facility (NIF) Using X-ray Spectroscopy

    Science.gov (United States)

    Barrios, Maria Alejandra

    2015-11-01

    Improved hohlraums will have a significant impact on increasing the likelihood of indirect drive ignition at the NIF. In indirect-drive Inertial Confinement Fusion (ICF), a high-Z hohlraum converts laser power into a tailored x-ray flux that drives the implosion of a spherical capsule filled with D-T fuel. The x-radiation drive to capsule coupling sets the velocity, adiabat, and symmetry of the implosion. Previous experiments in gas-filled hohlraums determined that the laser-hohlraum energy coupling is 20-25% less than modeled, therefore identifying energy loss mechanisms that reduce the efficacy of the hohlraum drive is central to improving implosion performance. Characterizing the plasma conditions, particularly the plasma electron temperature (Te) , is critical to understanding mechanism that affect the energy coupling such as the laser plasma interactions (LPI), hohlraum x-ray conversion efficiency, and dynamic drive symmetry. The first Te measurements inside a NIF hohlraum, presented here, were achieved using K-shell X-ray spectroscopy of an Mn-Co tracer dot. The dot is deposited on a thin-walled CH capsule, centered on the hohlraum symmetry axis below the laser entrance hole (LEH) of a bottom-truncated hohlraum. The hohlraum x-ray drive ablates the dot and causes it to flow upward, towards the LEH, entering the hot laser deposition region. An absolutely calibrated streaked spectrometer with a line of sight into the LEH records the temporal history of the Mn and Co X-ray emission. The measured (interstage) Lyα/ Heα line ratios for Co and Mn and the Mn-Heα/Co-Heα isoelectronic line ratio are used to infer the local plasma Te from the atomic physics code SCRAM. Time resovled x-ray images perpendicular to the hohlraum axis record the dot expansion and trajectory into the LEH region. The temporal evolution of the measured Te and dot trajectory are compared with simulations from radiation-hydrodynamic codes. This work was performed under the auspices of the U

  4. Upsurge of X-ray astronomy 230-

    International Nuclear Information System (INIS)

    Hudec, D.R.

    1978-01-01

    Instruments are described used for X-ray astronomy, namely X-ray detectors and X-ray telescopes. Unlike telescopes, the detectors do not comprise X-ray optics. A survey is given of the results obtained in solar and stellar X-ray astronomy and hypotheses are submitted on the origin of X radiation in the interstellar space. (J.B.)

  5. Hard X-ray sources from miniature plasma focus devices

    International Nuclear Information System (INIS)

    Raspa, V.; Silva, P.; Moreno, J.; Zambra, M.; Soto, L.

    2004-01-01

    As first stage of a program to design a repetitive pulsed radiation generator for industrial applications, two miniature plasma foci have been designed and constructed at the Chilean commission of nuclear energy. The devices operate at an energy level of the order of tens of joules (PF-50 J, 160 nF capacitor bank, 20-35 kV, 32-100 J, ∼ 150 ns time to peak current) and hundred of joules (PF-400 J, 880 nF, 20-35 kV, 176-539 J, ∼ 300 ns time to peak current). Hard X-rays are being studied in these devices operating with hydrogen. Images of metallic plates with different thickness were obtained on commercial radiographic film, Agfa Curix ST-G2, in order to characterize the energy of the hard X-ray outside of the discharge chamber of PF-400 J. An effective energy of the order of 90 keV was measured under those conditions. X ray images of different metallic objects also have been obtained. (authors)

  6. Hard X-ray sources from miniature plasma focus devices

    Energy Technology Data Exchange (ETDEWEB)

    Raspa, V. [Buenos Aires Univ., PLADEMA, CONICET and INFIP (Argentina); Silva, P.; Moreno, J.; Zambra, M.; Soto, L. [Comision Chilena de Energia Nuclear, Santiago (Chile)

    2004-07-01

    As first stage of a program to design a repetitive pulsed radiation generator for industrial applications, two miniature plasma foci have been designed and constructed at the Chilean commission of nuclear energy. The devices operate at an energy level of the order of tens of joules (PF-50 J, 160 nF capacitor bank, 20-35 kV, 32-100 J, {approx} 150 ns time to peak current) and hundred of joules (PF-400 J, 880 nF, 20-35 kV, 176-539 J, {approx} 300 ns time to peak current). Hard X-rays are being studied in these devices operating with hydrogen. Images of metallic plates with different thickness were obtained on commercial radiographic film, Agfa Curix ST-G2, in order to characterize the energy of the hard X-ray outside of the discharge chamber of PF-400 J. An effective energy of the order of 90 keV was measured under those conditions. X ray images of different metallic objects also have been obtained. (authors)

  7. X-ray measurements of MHD activity in shaped TCV plasmas

    International Nuclear Information System (INIS)

    Furno, I.; Weisen, H.; Moret, J.M.; Blanchard, P.; Anton, M.

    1997-01-01

    The ability of TCV to produce a wide variety of plasma shapes has allowed an investigation of MHD behaviour in a large number of limited ohmic L-mode discharges in which the elongation κ and the triangularity δ have been varied over a wide range: κ = 1.1 → 2.5, δ = -0.3 → 0.7. A 200 channel soft X-ray tomography system in conjunction with toroidal spaced soft X-ray diodes has been used to study the structure of internal disruptions and MHD modes. A strong reduction of sawtooth amplitude is observed as the plasma triangularity is decreased together with an increase in mode activity. The reduced sawtooth amplitudes are not correlated with any significant changes of the inversion radius and hence are not simply due to changes in current profiles; the inversion radius however is strongly correlated with the Spitzer conductivity profile and with the edge safety factor. (author) 5 figs., 4 refs

  8. Response of the upper atmosphere to variations in the solar soft x-ray irradiance. Ph.D. Thesis

    Science.gov (United States)

    Bailey, Scott Martin

    1995-01-01

    Terrestrial far ultraviolet (FUV) airglow emissions have been suggested as a means for remote sensing the structure of the upper atmosphere. The energy which leads to the excitation of FUV airglow emissions is solar irradiance at extreme ultraviolet (EUV) and soft x-ray wavelengths. Solar irradiance at these wavelengths is known to be highly variable; studies of nitric oxide (NO) in the lower thermosphere have suggested a variability of more than an order of magnitude in the solar soft x-ray irradiance. To properly interpret the FUV airflow, the magnitude of the solar energy deposition must be known. Previous analyses have used the electron impact excited Lyman-Birge-Hopfield (LBH) bands of N2 to infer the flux of photoelectrons in the atmosphere and thus to infer the magnitude of the solar irradiance. This dissertation presents the first simultaneous measurements of the FUV airglow, the major atmospheric constituent densities, and the solar EUV and soft x-ray irradiances. The measurements were made on three flights of an identical sounding rocket payload at different levels of solar activity. The linear response in brightness of the LBH bands to variations in solar irradiance is demonstrated. In addition to the N2 LBH bands, atomic oxygen lines at 135.6 and 130.4 nm are also studied. Unlike the LBH bands, these emissions undergo radiative transfer effects in the atmosphere. The OI emission at 135.6 nm is found to be well modeled using a radiative transfer calculation and the known excitation processes. Unfortunately, the assumed processes leading to OI 130.4 nm excitation are found to be insufficient to reproduce the observed variability of this emission. Production of NO in the atmosphere is examined; it is shown that a lower than previously reported variability in the solar soft x-ray irradiance is required to explain the variability of NO.

  9. Observation and theory of X-ray mirages.

    Science.gov (United States)

    Magnitskiy, Sergey; Nagorskiy, Nikolay; Faenov, Anatoly; Pikuz, Tatiana; Tanaka, Mamoko; Ishino, Masahiko; Nishikino, Masaharu; Fukuda, Yuji; Kando, Masaki; Kawachi, Tetsuya; Kato, Yoshiaki

    2013-01-01

    The advent of X-ray lasers allowed the realization of compact coherent soft X-ray sources, thus opening the way to a wide range of applications. Here we report the observation of unexpected concentric rings in the far-field beam profile at the output of a two-stage plasma-based X-ray laser, which can be considered as the first manifestation of a mirage phenomenon in X-rays. We have developed a method of solving the Maxwell-Bloch equations for this problem, and find that the experimentally observed phenomenon is due to the emergence of X-ray mirages in the plasma amplifier, appearing as phase-matched coherent virtual point sources. The obtained results bring a new insight into the physical nature of amplification of X-ray radiation in laser-induced plasma amplifiers and open additional opportunities for X-ray plasma diagnostics and extreme ultraviolet lithography.

  10. Charge exchange signatures in x-ray line emission accompanying plasma-wall interaction

    Czech Academy of Sciences Publication Activity Database

    Renner, Oldřich; Dalimier, E.; Liska, R.; Oks, E.; Šmíd, Michal

    2012-01-01

    Roč. 397, č. 1 (2012), s. 1-6 ISSN 1742-6588 R&D Projects: GA ČR GAP205/10/0814; GA ČR GAP208/10/2302; GA AV ČR IAAX00100903 Institutional research plan: CEZ:AV0Z10100523 Keywords : laser-produced plasma * particle jets generation * plasma-wall interaction * x-ray spectroscopy * charge exchange Subject RIV: BL - Plasma and Gas Discharge Physics

  11. CubeX: The CubeSAT X-ray Telescope for Elemental Abundance Mapping of Airless Bodies and X-ray Pulsar Navigation

    Science.gov (United States)

    Nittler, L. R.; Hong, J.; Kenter, A.; Romaine, S.; Allen, B.; Kraft, R.; Masterson, R.; Elvis, M.; Gendreau, K.; Crawford, I.; Binzel, R.; Boynton, W. V.; Grindlay, J.; Ramsey, B.

    2017-12-01

    The surface elemental composition of a planetary body provides crucial information about its origin, geological evolution, and surface processing, all of which can in turn provide information about solar system evolution as a whole. Remote sensing X-ray fluorescence (XRF) spectroscopy has been used successfully to probe the major-element compositions of airless bodies in the inner solar system, including the Moon, near-Earth asteroids, and Mercury. The CubeSAT X-ray Telescope (CubeX) is a concept for a 6U planetary X-ray telescope (36U with S/C), which utilizes Miniature Wolter-I X-ray optics (MiXO), monolithic CMOS and SDD X-ray sensors for the focal plane, and a Solar X-ray Monitor (heritage from the REXIS XRF instrument on NASA's OSIRIS-REx mission). CubeX will map the surface elemental composition of diverse airless bodies by spectral measurement of XRF excited by solar X-rays. The lightweight ( 1 kg) MiXO optics provide sub-arcminute resolution with low background, while the inherently rad-hard CMOS detectors provide improved spectral resolution ( 150 eV) at 0 °C. CubeX will also demonstrate X-ray pulsar timing based deep space navigation (XNAV). Successful XNAV will enable autonomous deep navigation with little to no support from the Deep Space Network, hence lowering the operation cost for many more planetary missions. Recently selected by NASA Planetary Science Deep Space SmallSat Studies, the first CubeX concept, designed to rideshare to the Moon as a secondary spacecraft on a primary mission, is under study in collaboration with the Mission Design Center at NASA Ames Research Center. From high altitude ( 6,000 km) frozen polar circular orbits, CubeX will study > 8 regions ( 110 km) of geological interest on the Moon over one year to produce a high resolution ( 2-3 km) elemental abundance map of each region. The novel focal plane design of CubeX also allows us to evaluate the performance of absolute navigation by sequential observations of several

  12. Development of Compton X-ray spectrometer for high energy resolution single-shot high-flux hard X-ray spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kojima, Sadaoki, E-mail: kojima-s@ile.osaka-u.ac.jp, E-mail: sfujioka@ile.osaka-u.ac.jp; Ikenouchi, Takahito; Arikawa, Yasunobu; Sakata, Shohei; Zhang, Zhe; Abe, Yuki; Nakai, Mitsuo; Nishimura, Hiroaki; Shiraga, Hiroyuki; Fujioka, Shinsuke, E-mail: kojima-s@ile.osaka-u.ac.jp, E-mail: sfujioka@ile.osaka-u.ac.jp; Azechi, Hiroshi [Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka 565-0871 (Japan); Ozaki, Tetsuo [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Miyamoto, Shuji; Yamaguchi, Masashi; Takemoto, Akinori [Laboratory of Advanced Science and Technology for Industry, University of Hyogo, 3-1-2 Kouto, Kamigori-cho, Ako-gun, Hyogo 678-1205 (Japan)

    2016-04-15

    Hard X-ray spectroscopy is an essential diagnostics used to understand physical processes that take place in high energy density plasmas produced by intense laser-plasma interactions. A bundle of hard X-ray detectors, of which the responses have different energy thresholds, is used as a conventional single-shot spectrometer for high-flux (>10{sup 13} photons/shot) hard X-rays. However, high energy resolution (Δhv/hv < 0.1) is not achievable with a differential energy threshold (DET) X-ray spectrometer because its energy resolution is limited by energy differences between the response thresholds. Experimental demonstration of a Compton X-ray spectrometer has already been performed for obtaining higher energy resolution than that of DET spectrometers. In this paper, we describe design details of the Compton X-ray spectrometer, especially dependence of energy resolution and absolute response on photon-electron converter design and its background reduction scheme, and also its application to the laser-plasma interaction experiment. The developed spectrometer was used for spectroscopy of bremsstrahlung X-rays generated by intense laser-plasma interactions using a 200 μm thickness SiO{sub 2} converter. The X-ray spectrum obtained with the Compton X-ray spectrometer is consistent with that obtained with a DET X-ray spectrometer, furthermore higher certainly of a spectral intensity is obtained with the Compton X-ray spectrometer than that with the DET X-ray spectrometer in the photon energy range above 5 MeV.

  13. Analysis of neon soft x-ray spectra from short-pulse laser-produced plasmas

    International Nuclear Information System (INIS)

    Abare, A.C.; Keane, C.J.; Crane, J.K.; DaSilva, L.B.; Lee, R.W.; Perry, M.D.; Falcone, R.W.

    1993-04-01

    We report preliminary results from the analysis of streaked soft x-ray neon spectra a gas jet target. In obtained from the interaction of a picosecond Nd:glass laser with these experiments streaked spectra show prompt harmonic emission followed by longer time duration soft x-ray line emission. The majority of the line emission observed was found to originate from Li- and Be-like Ne and the major transitions in the observed spectra have been identified. Li-like emission lines were observed to decay faster in time than Be-like transitions, suggesting that recombination is taking place. Line ratios of n=4-2 and n=3-2 transitions supported the view that these lines were optically thin and thick, respectively. The time history of Li-like Ne 2p-4d and 2p-3d lines is in good agreement with a simple adiabatic expansion model coupled to a time dependent collisional-radiative code. Further x-ray spectroscopic analysis is underway which is aimed at diagnosing plasma conditions and assessing the potential of this recombining neon plasma as a quasi-steady-state recombination x-ray laser medium

  14. Study of soft X-ray energy spectra from gas-puff Z-pinch plasma

    International Nuclear Information System (INIS)

    Zou Xiaobing; Wang Xinxin; Zhang Guixin; Han Min; Luo Chengmu

    2006-01-01

    A ROSS-FILTER-PIN spectrometer in the spectral range of 0.28 keV-1.56 keV was developed to study the soft X-ray radiation emitted from gas-puff Z-pinch plasma. It is composed of five channels covering the energy interval of interest without gaps. Soft X-ray spectral energy cuts were determined by the L absorption edges of selected filter elements (K absorption edges being used for light filter elements), and the optimum thickness of filter material was designed using computer code. To minimize the residual sensitivity outside the sensitivity range of each channel, element of the first filter was added into the second filter of all the Ross pair. To diminish the area of each filter, PIN detector with small sensitive area of 1 mm 2 was adopted for the spectrometer. A filter with small area is easy to fabricate and would be helpful to withstand the Z-pinch discharge shock wave. With this ROSS-FILTER-PIN spectrometer, the energy spectra of soft X-ray from a small gas-puff Z-pinch were investigated, and the correlation between the soft X-ray yield and the plasma implosion state was also studied. (authors)

  15. A soft X-ray image of the Moon

    International Nuclear Information System (INIS)

    Schmitt, J.H.M.M.; Aschenbach, B.; Hasinger, G.; Pfeffermann, E.; Predehl, P.; Truemper, J.; Snowden, S.L.; Wisconsin Univ., Madison, WI

    1991-01-01

    A soft X-ray image of the Moon obtained by the Roentgen Observatory Satellite ROSAT clearly shows a sunlit crescent, demonstrating that the Moon's X-ray luminosity arises from backscattering of solar X-rays. The Moon's optically dark side is also X-ray dark, and casts a distinct shadow on the diffuse cosmic X-ray background. Unexpectedly, the dark side seems to emit X-rays at a level about one per cent that of the bright side; this emission very probably results from energetic solar-wind electrons striking the Moon's surface. (author)

  16. X-ray and extreme ultraviolet emission from comets

    Science.gov (United States)

    Lisse, C. M.; Cravens, T. E.; Dennerl, K.

    The discovery of high energy X-ray emission in 1996 from C/1996 B2 (Hyakutake) has created a surprising new class of X-ray emitting objects. The original discovery (Lisse et al., 1996) and subsequent detection of X-rays from 17 other comets (Table 1) have shown that the very soft (E < 1 keV) emission is due to an interaction between the solar wind and the comet's atmosphere, and that X-ray emission is a fundamental property of comets. Theoretical and observational work has demonstrated that charge exchange collisions of highly charged solar wind ions with cometary neutral species is the best explanation for the emission. Now a rapidly changing and expanding field, the study of cometary X-ray emission appears to be able to lead us to a better understanding of a number of physical phenomena: the nature of the cometary coma, other sources of X-ray emission in the solar system, the structure of the solar wind in the heliosphere, and the source of the local soft X-ray background.

  17. Sub-keV, subnanosecond measurements of x-ray spectra from laser-produced plasmas

    International Nuclear Information System (INIS)

    Kornblum, H.N.; Koppel, L.N.; Slivinsky, V.W.; Glaros, S.S.; Ahlstrom, H.G.; Larsen, J.T.

    1977-01-01

    As part of the effort to extend our x-ray diagnostic capabilities, we have made x-ray spectral measurements of laser-produced plasmas for photon energies down to 100 eV with a time response of 0.5 nsec. Fast, windowless x-ray diodes were used in conjunction with critical angle reflecting mirrors and thin filters for energy definition for two channels, 300 to 600 eV and 800 to 1300 eV. A third channel, using only an x-ray diode and filter, provided spectral information in the 100 to 300 eV region. Results from exploding pusher targets will be presented and compared with those of other diagnostic techniques and Lasnex calculations. Future expansion and modifications of the present system will be discussed

  18. Soft X-ray spectroscopic investigation of a plasma focus operated in pure neon

    Energy Technology Data Exchange (ETDEWEB)

    Presura, R; Zoita, V; Paraschiv, I [Inst. of Physics and Technology of Radiation Devices, Bucharest (Romania)

    1997-12-31

    The soft X-ray emission of the medium-energy plasma focus device IPF-2/20 operated in pure neon was studied with spectral resolution. The spectra of H- and He-like Ne ions were recorded by means of a de Broglie spectrograph for initial filling pressures in the range 1.3 to 7 torr. Both the soft X-ray emission characteristics and the plasma parameters are strongly dependent on the working gas pressure. The intensity of the He-like neon ions lines increases when the working gas pressure is raised, while for the H-like ions it has a maximum for about 5 torr filling. The electron density has values of the order of 10{sup 20} cm{sup -3}. The electron temperature ranges between 300 and 350 eV. Both the plasma density and the plasma temperature decrease when the initial gas pressure is increased. (author). 2 figs., 9 refs.

  19. Soft X-ray spectroscopic investigation of a plasma focus operated in pure neon

    International Nuclear Information System (INIS)

    Presura, R.; Zoita, V.; Paraschiv, I.

    1996-01-01

    The soft X-ray emission of the medium-energy plasma focus device IPF-2/20 operated in pure neon was studied with spectral resolution. The spectra of H- and He-like Ne ions were recorded by means of a de Broglie spectrograph for initial filling pressures in the range 1.3 to 7 torr. Both the soft X-ray emission characteristics and the plasma parameters are strongly dependent on the working gas pressure. The intensity of the He-like neon ions lines increases when the working gas pressure is raised, while for the H-like ions it has a maximum for about 5 torr filling. The electron density has values of the order of 10 20 cm -3 . The electron temperature ranges between 300 and 350 eV. Both the plasma density and the plasma temperature decrease when the initial gas pressure is increased. (author). 2 figs., 9 refs

  20. Handbook of X-Ray Astronomy

    Science.gov (United States)

    Arnaud, Keith A. (Editor); Smith, Randall K.; Siemiginowska, Aneta

    2011-01-01

    X-ray astronomy was born in the aftermath of World War II as military rockets were repurposed to lift radiation detectors above the atmosphere for a few minutes at a time. These early flights detected and studied X-ray emission from the Solar corona. The first sources beyond the Solar System were detected during a rocket flight in 1962 by a team headed by Riccardo Giaccom at American Science and Engineering, a company founded by physicists from MIT. The rocket used Geiger counters with a system designed to reduce non-X-ray backgrounds and collimators limiting the region of sky seen by the counters. As the rocket spun, the field of view (FOV) happened to pass over what was later found to be the brightest non-Solar X-ray source; later designated See X-1. It also detected a uniform background glow which could not be resolved into individual sources. A follow-up campaign using X-ray detectors with better spatial resolution and optical telescopes identified See X-1 as an interacting binary with a compact (neutron star) primary. This success led to further suborbital rocket flights by a number of groups. More X-ray binaries were discovered, as well as X-ray emission from supernova remnants, the radio galaxies M87 and Cygnus-A, and the Coma cluster. Detectors were improved and Geiger counters were replaced by proportional counters, which provided information about energy spectra of the sources. A constant challenge was determining precise positions of sources as only collimators were available.

  1. Soft X-ray Tangential Imaging of the NSTX Core Plasma by Means of a MPGD Pin-hole Camera

    International Nuclear Information System (INIS)

    Pacella, D.; Leigheb, M.; Bellazzini, R.; Brez, A.; Finkenthal, M.; Stutman, D.; Kaita, R.; Sabbagh, S.A.

    2003-01-01

    A fast X-ray system based on a Micro Pattern Gas Detector has been used, for the first time, to investigate emission from the plasma core of the National Spherical Tokamak eXperiment (NSTX) at the Princeton Plasma Physics Laboratory. The results presented in this work demonstrate the capability of such a device to measure with a time resolution of the order of 1 ms the curvature and the elongation of the X-ray iso-emissivity contours, under various plasma conditions. Also, comparisons with the magnetic surface structure calculated by the EFIT code show good agreement between reconstructed flux surface and the soft X-ray emissions (SXR) for poloidal beta values up to 0.6. For greater values of beta, X-ray iso-emissivity contours become circular, while magnetic flux surface reconstructions yield elongation 1.5 < k < 2.2. The X-ray images have been acquired with a (statistical) signal to noise ratio (SNR) per pixel of about 30. Thanks to the direct and efficient X-ray conversion and its operation in a photon counting mode, this new diagnostic tool allows the routine investigation of the plasma core with a sampling rate of 1 kHz and extremely high SNR under all experimental conditions in NSTX

  2. Laser plasmas as x-ray sources for lithographic imaging of submicron structures

    International Nuclear Information System (INIS)

    Bijkerk, F.; van Dorssen, G.E.; van der Wiel, M.J.

    1988-01-01

    Laser radiation can be used efficiently to generate x-rays for lithographic imaging of submicron patterns, e.g., for VLSI device fabrication. Due to their short wavelength and high average power, excimer lasers show much potential for this application. Results are presented of scaling studies for high repetition rate excimer laser application, using the frequency doubled output of a low repetition rate Nd:YAG/Glass laser. Spectral and spatial characteristics of x-ray emission of the laser plasma are shown. The power density in the laser focus was 3 x 10 12 W/cm 2 . With this source Si x-ray masks with submicron Au absorber profiles are imaged into high sensitivity x-ray photoresist. For the exposures 80 laser shots sufficed to yield high quality submicron structures. Extrapolation of the results to a high power excimer laser reduces the exposure time of the photoresists to several seconds, enabling a wafer throughput at an industrial level

  3. The Focusing Optics X-ray Solar Imager Small Explorer Concept Mission

    Science.gov (United States)

    Christe, Steven; Shih, Albert Y.; Dennis, Brian R.; Glesener, Lindsay; Krucker, Sam; Saint-Hilaire, Pascal; Gubarev, Mikhail; Ramsey, Brian

    2016-05-01

    We present the FOXSI (Focusing Optics X-ray Solar Imager) small explorer (SMEX) concept, a mission dedicated to studying particle acceleration and energy release on the Sun. FOXSI is designed as a 3-axis stabilized spacecraft in low-Earth orbit making use of state-of-the-art grazing incidence focusing optics combined withpixelated solid-state detectors, allowing for direct imaging of solar X-rays. The current design being studied features multiple telescopes with a 14 meter focal length enabled by a deployable boom.FOXSI will observe the Sun in the 3-100 keV energy range. The FOXSI imaging concept has already been tested on two sounding rocket flights, in 2012 and 2014 and on the HEROES balloon payload flight in 2013. FOXSI will image the Sun with an angular resolution of 5'', a spectral resolution of 0.5 keV, and sub-second temporal resolution. FOXSI is a direct imaging spectrometer with high dynamic range and sensitivity and will provide a brand-new perspective on energy release on the Sun. We describe the mission and its science objectives.

  4. Efficient 'water window' soft x-ray high-Z plasma source

    International Nuclear Information System (INIS)

    Higashiguchi, T; Otsuka, T; Jiang, W; Endo, A; Li, B; Dunne, P; O'Sullivan, G

    2013-01-01

    Unresolved transition array (UTA) is scalable to shorter wavelengths, and we demonstrate a table-top broadband emission 'water window' soft x-ray source based on laser-produced plasmas. Resonance emission from multiply charged ions merges to produce intense UTAs in the 2 to 4 nm region, extending below the carbon K edge (4.37 nm). An outline of a microscope design for single-shot live cell imaging is proposed based on a bismuth (Bi) plasma UTA source, coupled to multilayer mirror optics

  5. Dense plasma focus x-ray source for sub-micron lithography

    International Nuclear Information System (INIS)

    Prasad, R.R.; Krishnan, M.; Mangano, J.; Greene, P.; Qi, Niansheng

    1993-01-01

    A discharge driven, dense plasma focus in neon is under development at SRL for use as a point x-ray source for sub-micron lithography. This source is presently capable of delivering ∼ 13j/pulse of neon K-shell x-rays (8--14 angstrom) into 4π steradians with 2 kj of electrical energy stored in the capacitor bank charged to 9 kV at a pulse repetition rate of 2 Hz. The discharge is produced by a ≤4 kj, ≤12 kV, capacitor bank circuit, which has a fixed inductance of 12 nH and drives ≤450 kA currents into the DPF load, with ∼1.1 μs rise-times. X-rays are produced when a dense pinch of neon is formed along the axis of the DPF electrodes. A new rail-gap switched capacitor bank and DPF have been built, designed for continuous operation at 2 Hz and burst mode operation at 20 Hz. This paper will present measurements of the x-ray output at a repetition rate of 2 Hz using the new capacitor bank. It will also describe measurements of the spot size (0.3--0.8 mm) and the spectrum (8--14 angstrom) of the DPF source. The dependence of these parameters on the DPF head geometry, bank energy and operating pressure will be discussed. The x-ray output has been measured using filtered pin diodes, x-ray diodes, and absolutely calibrated x-ray crystal spectra. Results from the source operating at 2 Hz will be presented. A novel concept of a windowless beamline has also been developed. The results of preliminary experiments to test the concept will be discussed. At a pulse repetition rate of 20 Hz, this source should produce 200--400 W of x-ray power in the 8-14 angstrom wavelength band, with an input power of 40--60 kW

  6. Plasma-enhanced atomic-layer-deposited MoO{sub x} emitters for silicon heterojunction solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Ziegler, Johannes; Schneider, Thomas; Sprafke, Alexander N. [Martin-Luther-University Halle-Wittenberg, mu-MD Group, Institute of Physics, Halle (Germany); Mews, Mathias; Korte, Lars [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Institute for Silicon-Photovoltaics, Berlin (Germany); Kaufmann, Kai [Fraunhofer Center for Silicon Photovoltaics CSP, Halle (Germany); University of Applied Sciences, Hochschule Anhalt Koethen, Koethen (Germany); Wehrspohn, Ralf B. [Martin-Luther-University Halle-Wittenberg, mu-MD Group, Institute of Physics, Halle (Germany); Fraunhofer Institute for Mechanics of Materials IWM Halle, Halle (Germany)

    2015-09-15

    A method for the deposition of molybdenum oxide (MoO{sub x}) with high growth rates at temperatures below 200 C based on plasma-enhanced atomic layer deposition is presented. The stoichiometry of the over-stoichiometric MoO{sub x} films can be adjusted by the plasma parameters. First results of these layers acting as hole-selective contacts in silicon heterojunction solar cells are presented and discussed. (orig.)

  7. The SMILE Soft X-ray Imager (SXI) CCD design and development

    Science.gov (United States)

    Soman, M. R.; Hall, D. J.; Holland, A. D.; Burgon, R.; Buggey, T.; Skottfelt, J.; Sembay, S.; Drumm, P.; Thornhill, J.; Read, A.; Sykes, J.; Walton, D.; Branduardi-Raymont, G.; Kennedy, T.; Raab, W.; Verhoeve, P.; Agnolon, D.; Woffinden, C.

    2018-01-01

    SMILE, the Solar wind Magnetosphere Ionosphere Link Explorer, is a joint science mission between the European Space Agency and the Chinese Academy of Sciences. The spacecraft will be uniquely equipped to study the interaction between the Earth's magnetosphere-ionosphere system and the solar wind on a global scale. SMILE's instruments will explore this science through imaging of the solar wind charge exchange soft X-ray emission from the dayside magnetosheath, simultaneous imaging of the UV northern aurora and in-situ monitoring of the solar wind and magnetosheath plasma and magnetic field conditions. The Soft X-ray Imager (SXI) is the instrument being designed to observe X-ray photons emitted by the solar wind charge exchange process at photon energies between 200 eV and 2000 eV . X-rays will be collected using a focal plane array of two custom-designed CCDs, each consisting of 18 μm square pixels in a 4510 by 4510 array. SMILE will be placed in a highly elliptical polar orbit, passing in and out of the Earth's radiation belts every 48 hours. Radiation damage accumulated in the CCDs during the mission's nominal 3-year lifetime will degrade their performance (such as through decreases in charge transfer efficiency), negatively impacting the instrument's ability to detect low energy X-rays incident on the regions of the CCD image area furthest from the detector outputs. The design of the SMILE-SXI CCDs is presented here, including features and operating methods for mitigating the effects of radiation damage and expected end of life CCD performance. Measurements with a PLATO device that has not been designed for soft X-ray signal levels indicate a temperature-dependent transfer efficiency performance varying between 5×10-5 and 9×10-4 at expected End of Life for 5.9 keV photons, giving an initial set of measurements from which to extrapolate the performance of the SXI CCDs.

  8. Soft x-ray microradiography and lithograph using a laser produced plasma source

    International Nuclear Information System (INIS)

    Cheng, P.C.

    1992-01-01

    Considering the hardware characteristics of the laser-induced plasma X-ray source and the limitations of the conventional cone-beam reconstruction algorithm, a general cone-beam reconstruction algorithm has been developed at our laboratory, in which the motion locus of the X-ray source is an arbitrary curve corresponding to at least a 2π continuous horizontal angular displacement in the coordinate system of the specimen. The preliminary simulation shows that the general cone-beam reconstruction algorithm consistently results in visually satisfactory images

  9. Time-resolved soft x-ray spectra from laser-produced Cu plasma

    International Nuclear Information System (INIS)

    Cone, K.V.; Dunn, J.; Baldis, H.A.; May, M.J.; Purvis, M.A.; Scott, H.A.; Schneider, M.B.

    2012-01-01

    The volumetric heating of a thin copper target has been studied with time resolved x-ray spectroscopy. The copper target was heated from a plasma produced using the Lawrence Livermore National Laboratory's Compact Multipulse Terrawatt (COMET) laser. A variable spaced grating spectrometer coupled to an x-ray streak camera measured soft x-ray emission (800-1550 eV) from the back of the copper target to characterize the bulk heating of the target. Radiation hydrodynamic simulations were modeled in 2-dimensions using the HYDRA code. The target conditions calculated by HYDRA were post-processed with the atomic kinetics code CRETIN to generate synthetic emission spectra. A comparison between the experimental and simulated spectra indicates the presence of specific ionization states of copper and the corresponding electron temperatures and ion densities throughout the laser-heated copper target.

  10. Solar and Stellar X-ray Cycles

    Science.gov (United States)

    Martens, P. C. H.; SADE Team

    2004-05-01

    Stern et al. have shown that Yohkoh-SXT full disk X-ray irradiance shows an 11 year cycle with an max/min amplitude ratio of a factor 30. Similar cyclic X-ray variation in Sun-like stars observed by ROSAT and its predecessors is observed in only a few cases and limited to a factor two or three. We will show, by means of detailed bandpass comparisons, that this discrepancy cannot be ascribed to the differences in energy response between SXT and the stellar soft X-ray detectors. Is the Sun exceptional? After centuries of geocentric and heliocentric worldviews we find this a difficult proposition to entertain. But perhaps the Sun is a member of a small class of late-type stars with large amplitudes in their X-ray cycles. The stellar X-ray observations listed in the HEASARC catalog are too sparse to verify this hypothesis. To resolve these and related questions we have proposed a small low-cost stellar X-ray spectroscopic imager originally called SADE to obtain regular time series from late and early-type stars and accretion disks. This instrument is complimentary to the much more advanced Chandra and XMM-Newton observatories, and allows them to focus on those sources that require their full spatial and spectral resolution. We will describe the basic design and spectroscopic capability of SADE and show it meets the mission requirements.

  11. Analysis of selected microflares observed by SphinX over the last minimum of solar activity

    Science.gov (United States)

    Siarkowski, Marek; Sylwester, Janusz; Sylwester, Barbara; Gryciuk, Magdalena

    The Solar Photometer in X-rays (SphinX) was designed to observe soft X-ray solar emission in the energy range between 1 keV and 15 keV with the resolution better than 0.5 keV. The instrument operated from February until November 2009 aboard CORONAS-Photon satellite, during the phase of exceptionally low minimum of solar activity. Here we use SphinX data for analysis of selected microflare-class events. We selected events of unusual lightcurves or location. Our study involves determination of temporal characteristics (times of start, maximum and end of flares) and analysis of physical conditions in flaring plasma (temperature, emission measure). Dedicated method has been used in order to remove emission not related to flare. Supplementary information about morphology and evolution of investigated events has been derived from the analysis of XRT/Hinode and SECCHI /STEREO images.

  12. Spatial and temporal structures of impulsive bursts from solar flares observed in UV and hard X-rays

    Science.gov (United States)

    Cheng, C.-C.; Tandberg-Hanssen, E.; Bruner, E. C.; Orwig, L.; Frost, K. J.; Kenny, P. J.; Woodgate, B. E.; Shine, R. A.

    1981-01-01

    New observations are presented of impulsive UV and hard X-rays bursts in two solar flares obtained with instruments on Solar Maximum Mission. The UV bursts were observed in the Si IV and O IV emission lines, whose intensity ratio is density-sensitive. By comparing the spatially resolved Si IV/O IV observations with the corresponding hard X-ray observations, it is possible to study their spatial and temporal relationships. For one flare, the individual component spikes in the multiply peaked hard X-ray burst can be identified with different discrete Si IV/O IV flaring kernels of size 4 arcsec x 4 arcsec or smaller, which brighten up sequentially in time. For the other, many Si IV/O kernels, widely distributed over a large area, show impulsive bursts at the same time, which correlate with the main peak of the impulsive hard X-ray burst. The density of the flaring Si IV/O IV kernels is in the range from 5 x 10 to the 12th-13th/cu cm.

  13. Measurement of the point spread function and effective area of the Solar-A Soft X-ray Telescope mirror

    Science.gov (United States)

    Lemen, J. R.; Claflin, E. S.; Brown, W. A.; Bruner, M. E.; Catura, R. C.

    1989-01-01

    A grazing incidence solar X-ray telescope, Soft X-ray Telescope (SXT), will be flown on the Solar-A satellite in 1991. Measurements have been conducted to determine the focal length, Point Spread Function (PSF), and effective area of the SXT mirror. The measurements were made with pinholes, knife edges, a CCD, and a proportional counter. The results show the 1/r character of the PSF, and indicate a half power diameter of 4.9 arcsec and an effective area of 1.33 sq cm at 13.3 A (0.93 keV). The mirror was found to provide a high contrast image with very little X-ray scattering.

  14. Multi-millijoule, deeply saturated x-ray laser at 21.2 nm for applications in plasma physics

    Czech Academy of Sciences Publication Activity Database

    Rus, Bedřich; Mocek, Tomáš; Präg R., Ansgar; Kozlová, Michaela; Hudeček, Miroslav; Jamelot, G.; Carillon, A.; Ros, D.; Lagron, J.C.; Joyeux, D.; Phalippou, D.

    2002-01-01

    Roč. 44, - (2002), s. B207-B223 ISSN 0741-3335 R&D Projects: GA MŠk LN00A100; GA AV ČR IAA1010014 Institutional research plan: CEZ:AV0Z1010921 Keywords : x-ray lasers * laser plasma * x-ray spectroscopy * x-ray optics Subject RIV: BH - Optics, Masers, Lasers Impact factor: 2.121, year: 2002

  15. Soft x-ray emission from postpulse expanding laser-produced plasmas

    International Nuclear Information System (INIS)

    Weaver, J.L.; Feldman, U.; Mostovych, A.N.; Seely, J.F.; Colombant, D.; Holland, G.

    2003-01-01

    A diagnostic spectrometer has been developed at the Naval Research Laboratory to measure the time resolved absolute intensity of radiation emitted from targets irradiated by the Nike laser. The spectrometer consists of a dispersive transmission grating of 2500 lines/mm or 5000 lines/mm and a detection system consisting of an absolutely calibrated Si photodiode array and a charge coupled device camera. In this article, this spectrometer was used to study the spatial distribution of soft x-ray radiation from low Z elements (primarily carbon) that lasted tens of nanoseconds after the main laser illumination was over. We recorded soft x-ray emission as a function of the target material and target orientation with respect to the incoming laser beam and the spectrometer line of sight. While a number of spectral features have been identified in the data, the instrument's combined temporal and spatial resolution allowed observation of the plasma expansion from CH targets for up to ∼25 ns after the cessation of the main laser pulse. The inferred plasma expansion velocities are slightly higher than those previously reported

  16. Soft x-ray emission from postpulse expanding laser-produced plasmas

    Science.gov (United States)

    Weaver, J. L.; Feldman, U.; Mostovych, A. N.; Seely, J. F.; Colombant, D.; Holland, G.

    2003-12-01

    A diagnostic spectrometer has been developed at the Naval Research Laboratory to measure the time resolved absolute intensity of radiation emitted from targets irradiated by the Nike laser. The spectrometer consists of a dispersive transmission grating of 2500 lines/mm or 5000 lines/mm and a detection system consisting of an absolutely calibrated Si photodiode array and a charge coupled device camera. In this article, this spectrometer was used to study the spatial distribution of soft x-ray radiation from low Z elements (primarily carbon) that lasted tens of nanoseconds after the main laser illumination was over. We recorded soft x-ray emission as a function of the target material and target orientation with respect to the incoming laser beam and the spectrometer line of sight. While a number of spectral features have been identified in the data, the instrument's combined temporal and spatial resolution allowed observation of the plasma expansion from CH targets for up to ˜25 ns after the cessation of the main laser pulse. The inferred plasma expansion velocities are slightly higher than those previously reported.

  17. Design of Molecular Solar Cells via Feedback from Soft X-ray Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Himpsel, Franz J. [Univ. of Wisconsin, Madison, WI (United States)

    2015-06-12

    Spectroscopy with soft X-rays was used to develop new materials and novel designs for solar cells and artificial photosynthesis. In order to go beyond the widely-used trial-and-error approach of gradually improving a particular design, we started from the most general layout of a solar cell (or a photo-electrochemical device) and asked which classes of materials are promising for best performance. For example, the most general design of a solar cell consists of a light absorber, an electron donor, and an electron acceptor. These are characterized by four energy levels, which were measured by a combination of spectroscopic X-ray techniques. Tuning synchrotron radiation to the absorption edges of specific elements provided element- and bond-selectivity. The spectroscopic results were complemented by state-of-the-art calculations of the electronic states. These helped explaining the observed energy levels and the orbitals associated with them. The calculations were extended to a large class of materials (for example thousands of porphyrin dye complexes) in order to survey trends in the energy level structure. A few highlights serve as examples: 1) Organic molecules combining absorber, donor, and acceptor with atomic precision. 2) Exploration of highly p-doped diamond films as inert, transparent electron donors. 3) Surface-sensitive characterization of nanorod arrays used as photoanodes in water splitting. 4) Computational design of molecular complexes for efficient solar cells using two photons.

  18. The spectrometer/telescope for imaging X-rays on board the ESA Solar Orbiter spacecraft

    International Nuclear Information System (INIS)

    Krucker, S.; Benz, A.O.; Hurford, G.J.; Arnold, N.G.; Orleański, P.; Gröbelbauer, H.-P.; Casadei, D.; Kobler, S.; Iseli, L.; Wiehl, H.J.; Csillaghy, A.; Etesi, L.; Hochmuth, N.; Battaglia, M.; Bednarzik, M.; Resanovic, R.; Grimm, O.; Viertel, G.; Commichau, V.; Howard, A.

    2013-01-01

    Solar Orbiter is a Sun-observing mission led by the European Space Agency, addressing the interaction between the Sun and the heliosphere. It will carry ten instruments, among them the X-ray imaging spectrometer STIX. STIX will determine the intensity, spectrum, timing, and location of thermal and accelerated electrons near the Sun through their bremsstrahlung X-ray emission. This report gives a brief overview of the STIX scientific goals and covers in more detail the instrument design and challenges

  19. Laboratory measurements of 50-300 eV X rays from collisions of cometary interest: Ne and S L X rays, Fe M X rays and others

    International Nuclear Information System (INIS)

    Verzani, C.J.; Miller, K.; Wrigley, A.; Kessel, Q.; Smith, W.W.; Smith, S.J.; Hossain, S.; Chutjian, A.

    2007-01-01

    Laboratory measurements simulating the impact of certain solar wind ions on CO have been made. Preliminary analysis of the X rays in the 50-300 eV energy range produced by these collisions suggests that a dominant role is played by electron capture and subsequent relaxation of the electron to the n = 2 levels of solar wind ions such as Ne and S. In particular our data show that X rays from Ne play a role that is at least as significant as that of the more dominant solar wind ion O 6+ in this X-ray energy range. It may be assumed that Mg and Si may also play an important role; however, these ions were not included in the present experiment

  20. X-ray radiation source based on a plasma filled diode

    Energy Technology Data Exchange (ETDEWEB)

    Popkov, N F; Kargin, V I; Ryaslov, E A; Pikar, A S [All-Russian Research Inst. of Experimental Physics, Sarov (Russian Federation). Russian Federal Nuclear Center

    1997-12-31

    The results are given of studies on a plasma X-ray source providing 2.5 krad of radiation dose per pulse over an area of 100 cm{sup 2} in the quantum energy range between 20 and 500 keV. The pulse duration was 100 ns. The spectral radiation distribution was obtained under various operating conditions of plasma and diode. A Marx generator served as the starting power source of 120 kJ with a discharge time of T/4=10{sup -6} s. A short electromagnetic pulse (10{sup -7} s) was shaped using plasma erosion opening switches. (author). 5 figs., 4 refs.

  1. Streaked spectrometry using multilayer x-ray-interference mirrors to investigate energy transport in laser-plasma applications

    International Nuclear Information System (INIS)

    Stradling, G.L.; Barbee, T.W. Jr.; Henke, B.L.; Campbell, E.M.; Mead, W.C.

    1981-08-01

    Transport of energy in laser-produced plasmas is scrutinized by devising spectrally and temporally identifiable characteristics in the x-ray emission history which identify the heat-front position at various times in the heating process. Measurements of the relative turn-on times of these characteristics show the rate of energy transport between various points. These measurements can in turn constrain models of energy transport phenomena. We are time-resolving spectrally distinguishable subkilovolt x-ray emissions from different layers of a disk target to examine the transport rate of energy into the target. A similar technique is used to measure the lateral expansion rate of the plasma spot. A soft x-ray streak camera with 15-psec temporal resolution is used to make the temporal measurements. Spectral discrimination of the incident signal is provided by multilayer x-ray interference mirrors

  2. Search for Solar Axions with the CCD Detector and X-ray Telescope at CAST Experiment

    CERN Document Server

    Rosu, Madalin Mihai; Zioutas, Konstantin

    2015-06-09

    The CERN Axion Solar Telescope (CAST) is an experiment that uses the world’s highest sensitivity Helioscope to date for solar Axions searches. Axions are weakly interacting pseudoscalar particles proposed to solve the so-called Strong Charge-Parity Problem of the Standard Model. The principle of detection is the inverse Primakoff Effect, which is a mechanism for converting the Axions into easily detectable X-ray photons in a strong transverse magnetic field. The solar Axions are produced due to the Primakoff effect in the hot and dense core of from the coupling of a real and a virtual photon. The solar models predict a peak Axion luminosity at an energy of 3 keV originating mostly from the inner 20% of the solar radius. Thus an intensity peak at an energy of 3 keV is also expected in the case of the X-ray radiation resulting from Axion conversion. CAST uses a high precision movement system for tracking the Sun twice a day with a LHC dipole twin aperture prototype magnet, 9.26 meters long and with a field of...

  3. Hard X-ray dosimetry of a plasma focus suitable for industrial radiography

    Science.gov (United States)

    Knoblauch, P.; Raspa, V.; Di Lorenzo, F.; Clausse, A.; Moreno, C.

    2018-04-01

    Dosimetric measurements of the hard X-ray emission by a small-chamber 4.7 kJ Mather-type plasma focus device capable of producing neat radiographs of metallic objects, were carried out with a set of thermoluminescent detectors TLD 700 (LiF:Mg,Ti). Measurements of the hard X-ray dose dependence with the angular position relative to the electrodes axis, are presented. The source-detector distance was changed in the range from 50 to 100 cm, and the angular positions were explored between ± 70°, relative to the symmetry axis of the electrodes. On-axis measurements show that the X-ray intensity is uniform within a half aperture angle of 6°, in which the source delivers an average dose of (1.5 ± 0.1) mGy/sr per shot. Monte Carlo calculations suggest that the energy of the electron beam responsible for the X-ray emission ranges 100-600 keV.

  4. Role of the Chandra X-Ray Observatory Observations for the Study of Ionized Plasmas

    Science.gov (United States)

    Weisskopf, Martin C.

    2010-01-01

    The Chandra X-Ray Observatory, launched in 1999, is now beginning its 12-th year of operation. Chandra, the X-ray component of NASA s Great Observatory program, continues to operate efficiently, somewhat remarkable considering that the Observatory was designed for three years of operation with a goal of five. The Observatory features X-ray optics with sub-arcsecond angular resolution and a small suite of instruments, including transmission gratings, which allow for high-resolution spectroscopy of point sources. We will detail the capabilities of the Observatory for making such spectroscopic measurements and discuss a number of examples of what has been learned about the astrophysical plasmas capable of producing bright X-ray emission.

  5. Short-time X-ray diffraction with an efficient-optimized, high repetition-rate laser-plasma X-ray-source

    International Nuclear Information System (INIS)

    Kaehle, Stephan

    2009-01-01

    This thesis deals with the production and application of ultrashort X-ray pulses. In the beginning different possibilities for the production of X-ray pulses with pulse durations of below one picosecond are presented, whereby the main topic lies on the so called laser-plasma X-ray sources with high repetition rate. In this case ultrashort laser pulses are focused on a metal, so that in the focus intensities of above 10 16 W/cm 2 dominate. In the ideal case in such way ultrafast electrons are produced, which are responsible for line radiation. In these experiments titanium K α radiation is produced, thes photons possess an energy of 4.51 keV. For the efficient production of line radiation here the Ti:Sa laser is optimized in view of the laser energy and the pulse shape and the influence of the different parameters on the K α production systematically studied. The influences of laser intensity, system-conditioned pre-pulses and of phase modulation are checked. It turns out that beside the increasement of the K α radiation by a suited laser intensity a reduction of the X-ray background radiation is of deciding importance for the obtaining of clear diffraction images. This background radiation is mainly composed of bremsstrahlung. It can be suppressed by the avoidance of intrinsic pre-pulses and by means of 2nd-order phase modulation. By means of optical excitation and X-ray exploration experiments the production of acoustic waves after ultrashort optical excitation in a 150 nm thick Ge(111) film on Si(111) is studied. These acoustic waves are driven by thermal (in this time scale time-independent) and electronic (time dependent) pressure amounts. As essential results it turns out that the relative amount of the electronic pressure increases with decreasing excitation density [de

  6. X-ray laser studies using plasmas created by optical field ionization

    International Nuclear Information System (INIS)

    Krushelnick, K.M.; Tighe, W.; Suckewer, S.

    1995-01-01

    X-ray laser experiments involving the creation of fast recombining plasmas by optical field ionization of preformed targets were conducted. A nonlinear increase in the intensity of the 13.5nm Lyman-α line in Li III with the length of the target plasma was observed but only for distances less than the laser confocal parameter and for low plasma electron temperatures. Multiphoton pumping of resonant atomic transitions was also examined and the process of multiphoton ionization of FIII was found to be more probable than multiphoton excitation

  7. X-ray spectroscopic diagnostics of high-temperature dense plasmas created in different gaseous media

    International Nuclear Information System (INIS)

    Skobelev, I.Y.; Dyakin, V.M.; Faenov, A.Y.

    1997-01-01

    The investigations of emission x-ray spectra of multicharged ions of some chemical elements (S, F, Ar, Fr, O) have been carried out. These atoms are contained in gases and consequently can be used as diagnostic elements in a dense plasma focus experiments. The investigations were done in the dense high-temperature plasma (N e ∼ 10 21 cm -3 , T e ∼ 500 eV) created by laser heating of high-pressure gas puff targets, and X-ray spectrographs with a spherically bent mica crystals were used for spectra observations. Some new spectroscopic results (line identifications, high-precision wavelength measurements) have been obtained and have been applied to determine a spatial distribution of plasma parameters. It is shown that spectroscopic techniques used is a very suitable tool for studies of a plasma with complicated spatial structure

  8. Soft x-ray Planetary Imager

    Data.gov (United States)

    National Aeronautics and Space Administration — The project is to prototype a soft X-ray Imager for planetary applications that has the sensitivity to observe solar system sources of soft  X-ray emission. A strong...

  9. Impulsive behavior in solar soft X-radiation

    Science.gov (United States)

    Hudson, H. S.; Strong, K. T.; Dennis, B. R.; Zarro, D.; Inda, M.; Kosugi, T.; Sakao, T.

    1994-01-01

    The Yohkoh soft X-ray telescope has observed impulsive, thermal, soft X-ray emission at the footpoints of magnetic loops during solar flares. The soft X-ray (thermal) time profiles at the footpoints closely match the hard X-ray (nonthermal) time profiles, directly demonstrating the heating of the lower solar atmosphere on short timescales during the interval of nonthermal energy release. This phenomenon is the rule, rather than the exception, occurring in the majority of flares that we have examined with the Yohkoh data. We illustrate the impulsive behavior with data from the major flare of 1992 January 26. For this flare, the soft X-ray peak times matched the hard X-ray peak times within the time resolution of the soft X-ray measurements (about 10 s), and the soft and hard X-ray locations match within the resolution of the hard X-ray imager. The impulsive soft X-ray emission clearly has a thermal spectral signature, but not at the high temperature of a 'superhot' source. We conclude that the impulsive soft X-ray emission comes from material heated by precipitating electrons at loop footpoints and evaporating from the deeper atmosphere into the flaring flux tube.

  10. New solar broad-band hard X-ray spectrometer: first results

    Czech Academy of Sciences Publication Activity Database

    Fárník, František; Garcia, H.; Karlický, Marian

    2001-01-01

    Roč. 201, č. 2 (2001), s. 357-372 ISSN 0038-0938 R&D Projects: GA ČR GA205/00/1726; GA AV ČR IAA3003003; GA AV ČR IBS1003006; GA AV ČR KSK2043105; GA AV ČR IAA303108 Institutional research plan: CEZ:AV0Z1003909 Keywords : X-ray * spectrometer * solar flare * radio emission Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 2.103, year: 2001

  11. Instantaneous x-ray radiation energy from laser produced polystyrene plasmas for shock ignition conditions

    International Nuclear Information System (INIS)

    Shang, Wanli; Wei, Huiyue; Li, Zhichao; Yi, Rongqing; Zhu, Tuo; Song, Tianmin; Huang, Chengwu; Yang, Jiamin

    2013-01-01

    Laser target energy coupling mechanism is crucial in the shock ignition (SI) scheme, and x-ray radiation energy is a non-negligible portion of the laser produced plasma energy. To evaluate the x-ray radiation energy amount at conditions relevant to SI scheme, instantaneous x-ray radiation energy is investigated experimentally with continuum phase plates smoothed lasers irradiating layer polystyrene targets. Comparative laser pulses without and with shock spike are employed. With the measured x-ray angular distribution, full space x-ray radiation energy and conversion efficiency are observed. Instantaneous scaling law of x-ray conversion efficiency is obtained as a function of laser intensity and time. It should be pointed out that the scaling law is available for any laser pulse shape and intensity, with which irradiates polystyrene planar target with intensity from 2 × 10 14 to 1.8 × 10 15 W/cm 2 . Numerical analysis of the laser energy transformation is performed, and the simulation results agree with the experimental data

  12. Bent crystal X-ray optics for the diagnosis and applications of laser-produced plasmas

    International Nuclear Information System (INIS)

    Loetzsch, Robert

    2012-01-01

    The present thesis discussed several aspects of X-ray optics based on bent crystals and a number of applications of these optics. First, a deeper insight into the reflection properties of elastically bent perfect crystal optics was gained by the consideration of all deformation effects. It was shown that the reflection properties depend on the lateral position on the crystal, an effect that was not addressed before, neither experimentally nor theoretically. To investigate this effect, an apparatus for the measurement of Bragg angles of bent crystals with high angular resolution was built. It was measured that the lattice plane distances of two-dimensionally bent crystals vary laterally by up to 10 -4 . This effect has to be considered in high resolution X-ray spectroscopy and imaging with these bent crystals. It can explain discrepancies in theoretical and experimental spectrometer resolution with spherically bent crystals. Besides these principal investigations, in this thesis a number of X-ray optics were presented that demonstrate the application potential of bent crystal optics. This includes two optics that are used in the field of applications of laser-produced plasmas as high repeating hard X-ray sources. It was shown that an X-ray spectrometer based on full cylinder rings of highly oriented pyrolytic graphite is capable to record the rather weak single shot pulses from a high repeating 1 er-plasma X-ray source. This is possible due to the high collection efficiency of the instrument of up to 5.10 -4 . Furthermore, X-ray optics based on toroidally bent crystals that make it possible to spectrally select a bandwidth of ∝1 eV and focus the ultrashort X-ray pulses from such a laser-plasma source, were designed, prepared and characterized. It was shown that these bent crystals provide the calculated integrated reflectivity, the predicted bandwidth and focus to spot sizes smaller than 60 μm. A novel application of toroidally bent crystals was pointed out: a

  13. On Lunar Exospheric Column Densities and Solar Wind Access Beyond the Terminator from ROSAT Soft X-Ray Observations of Solar Wind Charge Exchange

    Science.gov (United States)

    Collier, Michael R.; Snowden, S. L.; Sarantos, M.; Benna, M.; Carter, J. A.; Cravens, T. E.; Farrell, W. M.; Fatemi, S.; Hills, H. Kent; Hodges, R. R.; hide

    2014-01-01

    We analyze the Rontgen satellite (ROSAT) position sensitive proportional counter soft X-ray image of the Moon taken on 29 June 1990 by examining the radial profile of the surface brightness in three wedges: two 19 deg wedges (one north and one south) 13-32 deg off the terminator toward the dark side and one wedge 38 deg wide centered on the antisolar direction. The radial profiles of both the north and the south wedges show significant limb brightening that is absent in the 38 deg wide antisolar wedge. An analysis of the soft X-ray intensity increase associated with the limb brightening shows that its magnitude is consistent with that expected due to solar wind charge exchange (SWCX) with the tenuous lunar atmosphere based on lunar exospheric models and hybrid simulation results of solar wind access beyond the terminator. Soft X-ray imaging thus can independently infer the total lunar limb column density including all species, a property that before now has not been measured, and provide a large-scale picture of the solar wind-lunar interaction. Because the SWCX signal appears to be dominated by exospheric species arising from solar wind implantation, this technique can also determine how the exosphere varies with solar wind conditions. Now, along with Mars, Venus, and Earth, the Moon represents another solar system body at which SWCX has been observed.

  14. Producing x-rays

    International Nuclear Information System (INIS)

    Mallozzi, P.J.; Epstein, H.M.; Jung, R.G.; Applebaum, D.C.; Fairand, B.P.; Gallagher, W.J.

    1977-01-01

    A method of producing x-rays by directing radiant energy from a laser onto a target is described. Conversion efficiency of at least about 3 percent is obtained by providing the radiant energy in a low-power precursor pulse of approximately uniform effective intensity focused onto the surface of the target for about 1 to 30 nanoseconds so as to generate an expanding unconfined coronal plasma having less than normal solid density throughout and comprising a low-density (underdense) region wherein the plasma frequency is less than the laser radiation frequency and a higher-density (overdense) region wherein the plasma frequency is greater than the laser radiation frequency and, about 1 to 30 nanoseconds after the precursor pulse strikes the target, a higher-power main pulse focused onto the plasma for about 10 -3 to 30 nanoseconds and having such power density and total energy that the radiant energy is absorbed in the underdense region and conducted into the overdense region to heat it and thus to produce x-rays therefrom with the plasma remaining substantially below normal solid density and thus facilitating the substantial emission of x-rays in the form of spectral lines arising from nonequilibrium ionization states

  15. Implications of the Detection of X-rays From Pluto by Chandra for Its Solar Wind - Neutral Atmosphere Interaction

    Science.gov (United States)

    Lisse, C. M.

    2016-12-01

    Using the Chandra X-Ray Observatory, we have obtained low-resolution imaging X-ray spectrophotometry of the Pluto system in support of the New Horizons (NH) flyby. In a total of 174 ksec of on-target time, we measured 8 photons from 0.31 to 0.60 keV in a co-moving 11 x 11 pixel2 box (the 90% flux aperture for fixed background sources in the field) measuring 121,000 x 121,000 km2 (or 100 x 100 RPluto) at Pluto. The Pluto photons do not have the spectral shape of the background, are coincident with a 90% flux aperture co-moving with Pluto, and are not confused with any background source, so we consider them as sourced from the Pluto system. Allowing for background, we find a net signal of 6.8 counts and a statistical noise level of 1.2 counts, for a detection of Pluto at > 99.95%. The mean 0.31 - 0.60 keV X-ray power from Pluto is 200 +200/-100 MW, in the middle range of X-ray power levels seen for other known solar system emission sources: auroral precipitation, solar X-ray scattering, and charge exchange (CXE) between solar wind (SW) ions and atmospheric neutrals. We eliminate auroral effects as a source, as Pluto has no known magnetic field and the NH/Alice UV spectrometer detected no airglow from Pluto during the flyby. Atmospheric haze particles could produce resonant scattering of solar X-rays from Pluto, but the energy signature of the detected photons does not match the solar spectrum and estimates of Pluto's scattered X-ray emission are 2 to 3 orders of magnitude lower than seen in our observations. CXE-driven emission from hydrogenic and heliogenic SW carbon, nitrogen, and oxygen ions can produce the energy signature seen, and the 6 x 1025 neutral gas escape rate from Pluto deduced from NH data (Gladstone et al. 2016) can support the 3.0 +3.0/-1.5 x 1024 X-ray photons/s emission rate required by our observations. Using the SW proton density and speed measured by the NH/SWAP instrument in the vicinity of Pluto at the time of the photon emissions, we find a

  16. High-spatial resolution and high-spectral resolution detector for use in the measurement of solar flare hard x rays

    International Nuclear Information System (INIS)

    Desai, U.D.; Orwig, L.E.

    1988-01-01

    In the areas of high spatial resolution, the evaluation of a hard X-ray detector with 65 micron spatial resolution for operation in the energy range from 30 to 400 keV is proposed. The basic detector is a thick large-area scintillator faceplate, composed of a matrix of high-density scintillating glass fibers, attached to a proximity type image intensifier tube with a resistive-anode digital readout system. Such a detector, combined with a coded-aperture mask, would be ideal for use as a modest-sized hard X-ray imaging instrument up to X-ray energies as high as several hundred keV. As an integral part of this study it was also proposed that several techniques be critically evaluated for X-ray image coding which could be used with this detector. In the area of high spectral resolution, it is proposed to evaluate two different types of detectors for use as X-ray spectrometers for solar flares: planar silicon detectors and high-purity germanium detectors (HPGe). Instruments utilizing these high-spatial-resolution detectors for hard X-ray imaging measurements from 30 to 400 keV and high-spectral-resolution detectors for measurements over a similar energy range would be ideally suited for making crucial solar flare observations during the upcoming maximum in the solar cycle

  17. Dense X-pinch plasmas for x-ray microlithography

    International Nuclear Information System (INIS)

    Kalantar, D.H.; Hammer, D.A.; Qi, N.; Mittal, K.C.

    1990-01-01

    The authors report experimental results from a study of the radiation emission from aluminum and magnesium x-pinch experiments. The single cross x-pinch, driven by the 0.5 TW, 40ns pulse width Lion accelerator, consists of 2-8 fine wires stretched between the output electrodes of Lion so as to touch at a single point. The wires were twisted up to 360 degrees at the crossing point. The number and size of Al and Mg wires were varied in order to optimize the K-shell line radiation. Diagnostics used for the experiments included pinhole photography, streak imaging, filtered photoconducting diodes and x-ray crystal spectroscopy. The source size and distribution are determined through x-ray pinhole photographs. The radiation energy spectrum is determined by x-ray spectroscopy and attenuation through filters. Energy intensities were obtained from the filtered photoconducting diodes

  18. Electron acceleration and generation of high-brilliance x-ray radiation in kilojoule, subpicosecond laser-plasma interactions

    Directory of Open Access Journals (Sweden)

    J. Ferri

    2016-10-01

    Full Text Available Petawatt, picosecond laser pulses offer rich opportunities in generating synchrotron x-rays. This paper concentrates on the regimes accessible with the PETAL laser, which is a part of the Laser Megajoule (LMJ facility. We explore two physically distinct scenarios through Particle-in-Cell simulations. The first one realizes in a dense plasma, such that the period of electron Langmuir oscillations is much shorter than the pulse duration. Hallmarks of this regime are longitudinal breakup (“self-modulation” of the picosecond-scale laser pulse and excitation of a rapidly evolving broken plasma wake. It is found that electron beams with a charge of several tens of nC can be obtained, with a quasi-Maxwellian energy distribution extending to a few-GeV level. In the second scenario, at lower plasma densities, the pulse is shorter than the electron plasma period. The pulse blows out plasma electrons, creating a single accelerating cavity, while injection on the density downramp creates a nC quasi-monoenergetic electron bunch within the cavity. This bunch accelerates without degradation beyond 1 GeV. The x-ray sources in the self-modulated regime offer a high number of photons (∼10^{12} with the slowly decaying energy spectra extending beyond 60 keV. In turn, quasimonoenergetic character of the electron beam in the blowout regime results in the synchrotron-like spectra with the critical energy around 10 MeV and a number of photons >10^{9}. Yet, much smaller source duration and transverse size increase the x-ray brilliance by more than an order of magnitude against the self-modulated case, also favoring high spatial and temporal resolution in x-ray imaging. In all explored cases, accelerated electrons emit synchrotron x-rays of high brilliance, B>10^{20}  photons/s/mm^{2}/mrad^{2}/0.1%BW. Synchrotron sources driven by picosecond kilojoule lasers may thus find an application in x-ray diagnostics on such facilities such as the LMJ or National

  19. Rocket studies of solar corona and transition region. [X-Ray spectrometer/spectrograph telescope

    Science.gov (United States)

    Acton, L. W.; Bruner, E. C., Jr.; Brown, W. A.; Nobles, R. A.

    1979-01-01

    The XSST (X-Ray Spectrometer/Spectrograph Telescope) rocket payload launched by a Nike Boosted Black Brant was designed to provide high spectral resolution coronal soft X-ray line information on a spectrographic plate, as well as time resolved photo-electric records of pre-selected lines and spectral regions. This spectral data is obtained from a 1 x 10 arc second solar region defined by the paraboloidal telescope of the XSST. The transition region camera provided full disc images in selected spectral intervals originating in lower temperature zones than the emitting regions accessible to the XSST. A H-alpha camera system allowed referencing the measurements to the chromospheric temperatures and altitudes. Payload flight and recovery information is provided along with X-ray photoelectric and UV flight data, transition camera results and a summary of the anomalies encountered. Instrument mechanical stability and spectrometer pointing direction are also examined.

  20. Determination of Differential Emission Measure Distribution of Coronal Structures Observed by SphinX During Recent Minimum of Solar Activity

    Science.gov (United States)

    Kepa, Anna; Gburek, Szymon; Siarkowski, Marek; Sylwester, Barbara; Sylwester, Janusz; Kowalinski, Miroslaw

    SphinX is a high-sensitivity soft X-ray spectrophotometer which measures soft X-ray spectra in the energy range between 0.8 keV and 15 keV. From February to November 2009 the instrument has observed unusually quiet solar coronal emission as well as a number of weak solar flares. Based on SphinX spectra it is possible to study the differential emission measure distributions (DEM) in the temperature range roughly between 1 MK and 10 MK. The aim of the present study is to unveil DEM plasma distributions for selected activity conditions and analyze their variability.

  1. Surface modification of porous nanocrystalline TiO2 films for dye-sensitized solar cell application by various gas plasmas

    International Nuclear Information System (INIS)

    Kim, Youngsoo; Yoon, Chang-Ho; Kim, Kang-Jin; Lee, Yeonhee

    2007-01-01

    Titanium dioxide (TiO 2 ) film for dye-sensitized solar cells (DSSCs) has surface defects such as oxygen vacancies created during the annealing process. The authors used a plasma treatment technique to reduce defects on TiO 2 surfaces. They investigated the influence of different gas plasma treatments of TiO 2 film on the photoelectric performance of DSSC. Short-circuit photocurrent density (J sc ), open-circuit photovoltage (V oc ), and the amount of adsorbed dye for DSSCs were measured. As a result, the solar-to-electricity conversion efficiencies of the O 2 - and N 2 -treated cells increased by 15%-20% compared to untreated cells. On the other hand, solar energy conversion efficiency of CF 4 -plasma treated cells decreased drastically. The increased amount of adsorbed dye on the TiO 2 film was measured by time-of-flight secondary ion mass spectrometry. TiO 2 surfaces modified by plasma treatment were characterized using analytical instruments such as x-ray photoelectron spectroscopy and near-edge x-ray absorption fine structure

  2. Velocity gradient induced line splitting in x-ray emission accompanying plasma-wall interaction

    Czech Academy of Sciences Publication Activity Database

    Šmíd, Michal; Renner, Oldřich; Liska, R.

    2013-01-01

    Roč. 125, Aug (2013), s. 38-44 ISSN 0022-4073 R&D Projects: GA ČR GAP205/10/0814; GA ČR GAP205/11/0571 Institutional support: RVO:68378271 Keywords : laser-produced plasmas * x-ray spectroscopy * plasma-wall interaction * spectral line profiles * Doppler shift * ion velocity gradients Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 2.288, year: 2013

  3. Observations of non-collective x-ray scattering in warm dense carbon plasma

    International Nuclear Information System (INIS)

    Bao Lihua; Zhang Jiyan; Zhao Yang; Ding Yongkun; Zhang Xiaoding

    2012-01-01

    An experiment for observing the spectrally resolved non-collective x-ray scattering in warm dense carbon plasma is presented in this paper. The experiment used Ta M-band x-rays to heat a foamed carbon cylinder sample isochorically and measured the scattering spectrum with a HOPG crystal spectrometer. The spectrum was compared with the calculation results using a Born-Mermin-approximation model. The best fitting was found at an electron temperature of T e =34 eV and an electron density of n e =1.6×10 23 cm −3 .

  4. Multiframe, Single Line-of-Sight X-Ray Imager for Burning Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Baker, Kevin L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-01-28

    The purpose of this LDRD project was to demonstrate high spatial and temporal resolution x-ray imaging using optical detectors, and in particular the VISAR and OHRV diagnostics on the OMEGA laser. The x-ray source being imaged was a backlighter capsule being imploded by 39 beams of the OMEGA laser. In particular this approach utilized a semiconductor with the side facing the backlighter capsule coated with a thin aluminum layer to allow x rays to pass through the metal layer and then get absorbed in the semiconductor. The other side of the semiconductor was AR coated to allow the VISAR or OHRV probe beam to sample the phase change of the semiconductor as the x rays were absorbed in the semiconductor. This technique is capable of acquiring sub-picosecond 2-D or 1-D x-ray images, detector spatial resolution of better than 10 um and the ability to operate in a high neutron flux environment expected on ignition shots with burning plasmas. In addition to demonstrating this technique on the OMEGA laser, several designs were made to improve the phase sensitivity, temporal resolution and number of frames over the existing diagnostics currently implemented on the OMEGA laser. These designs included both 2-d imaging diagnostics as well as improved 1-D imaging diagnostics which were streaked in time.

  5. X-Ray Emission Properties of Supernova Remnants

    NARCIS (Netherlands)

    Vink, J.; Alsabti, A.W.; Murdin, P.

    2016-01-01

    X-ray emission from supernova remnants can be broadly divided into thermal X-ray emission from the shock-heated plasmas and in nonthermal (synchrotron) emission caused by very high-energy (10–100 TeV) electrons moving in the magnetic fields of the hot plasmas. The thermal X-ray emission of young

  6. Applicability of X-ray reflectometry to studies of polymer solar cell degradation

    DEFF Research Database (Denmark)

    Andreasen, Jens Wenzel; Gevorgyan, Suren; Schleputz, C.M.

    2008-01-01

    Although degradation of polymer solar cells is widely acknowledged, the cause, physical or chemical, has not been identified. The purpose of this work is to determine the applicability of X-ray reflectometry for in situ observation of physical degradation mechanisms. We find that the rough...... interfaces of the polymer solar cell constituent layers seriously obstruct the sensitivity of the technique, rendering it impossible to elucidate changes in the layer/interface structure at the sub-nanometer level. (c) 2008 Elsevier B.V. All rights reserved....

  7. Higher order structure analysis of nano-materials by spectral reflectance of laser-plasma soft x-ray

    International Nuclear Information System (INIS)

    Azuma, Hirozumi; Takeichi, Akihiro; Noda, Shoji

    1995-01-01

    We have proposed a new experimental arrangement to measure spectral reflectance of nano-materials for analyzing higher order structure with laser-plasma soft x-rays. Structure modification of annealed Mo/Si multilayers and a nylon-6/clay hybrid with poor periodicity was investigated. The measurement of the spectral reflectance of soft x-rays from laser-produced plasma was found to be a useful method for the structure analysis of nano-materials, especially those of rather poor periodicity

  8. Ionospheric Effects of X-Ray Solar Bursts in the Brazilian Sector

    Science.gov (United States)

    Becker-Guedes, F.; Takahashi, H.; Costa, J. E.; Otsuka, Y.

    2011-12-01

    When the solar X-ray flux in the interplanetary medium reaches values above a certain threshold, some undesired effects affecting radio communications are expected. Basically, the magnitudes of these effects depend on the X-ray peak brightness and duration, which drive the intensity of the ionosphere response when the associated electromagnetic wave hit the sunlit side of the Earth atmosphere. An important aspect defining the severity of damages to HF radio communications and LF navigation signals in a certain area is the local time when each event takes place. In order to create more accurate warnings referred to possible radio signal loss or degradation in the Brazilian sector, we analyze TEC maps obtained by a GPS network, formed by dual-frequency receivers spread all over the country, to observe ionospheric local changes during several X-ray events in the 0.1-0.8 nm range measured by GOES satellite. Considering the duration, peak brightness, and local time of the events, the final purpose of this study is to understand and predict the degree of changes suffered by the ionosphere during these X-ray bursts. We intend using these results to create a radio blackout warning product to be offered by the Brazilian space weather program named EMBRACE (Estudo e Monitoramento BRAsileiro do Clima Espacial): Brazilian Monitoring and Study of Space Weather.

  9. AUTOMATED SOLAR FLARE STATISTICS IN SOFT X-RAYS OVER 37 YEARS OF GOES OBSERVATIONS: THE INVARIANCE OF SELF-ORGANIZED CRITICALITY DURING THREE SOLAR CYCLES

    International Nuclear Information System (INIS)

    Aschwanden, Markus J.; Freeland, Samuel L.

    2012-01-01

    We analyzed the soft X-ray light curves from the Geostationary Operational Environmental Satellites over the last 37 years (1975-2011) and measured with an automated flare detection algorithm over 300,000 solar flare events (amounting to ≈5 times higher sensitivity than the NOAA flare catalog). We find a power-law slope of α F = 1.98 ± 0.11 for the (background-subtracted) soft X-ray peak fluxes that is invariant through three solar cycles and agrees with the theoretical prediction α F = 2.0 of the fractal-diffusive self-organized criticality (FD-SOC) model. For the soft X-ray flare rise times, we find a power-law slope of α T = 2.02 ± 0.04 during solar cycle minima years, which is also consistent with the prediction α T = 2.0 of the FD-SOC model. During solar cycle maxima years, the power-law slope is steeper in the range of α T ≈ 2.0-5.0, which can be modeled by a solar-cycle-dependent flare pile-up bias effect. These results corroborate the FD-SOC model, which predicts a power-law slope of α E = 1.5 for flare energies and thus rules out significant nanoflare heating. While the FD-SOC model predicts the probability distribution functions of spatio-temporal scaling laws of nonlinear energy dissipation processes, additional physical models are needed to derive the scaling laws between the geometric SOC parameters and the observed emissivity in different wavelength regimes, as we derive here for soft X-ray emission. The FD-SOC model also yields statistical probabilities for solar flare forecasting.

  10. Plasma instability control toward high fluence, high energy x-ray continuum source

    Science.gov (United States)

    Poole, Patrick; Kirkwood, Robert; Wilks, Scott; Blue, Brent

    2017-10-01

    X-ray source development at Omega and NIF seeks to produce powerful radiation with high conversion efficiency for material effects studies in extreme fluence environments. While current K-shell emission sources can achieve tens of kJ on NIF up to 22 keV, the conversion efficiency drops rapidly for higher Z K-alpha energies. Pulsed power devices are efficient generators of MeV bremsstrahlung x-rays but are unable to produce lower energy photons in isolation, and so a capability gap exists for high fluence x-rays in the 30 - 100 keV range. A continuum source under development utilizes instabilities like Stimulated Raman Scattering (SRS) to generate plasma waves that accelerate electrons into high-Z converter walls. Optimizing instabilities using existing knowledge on their elimination will allow sufficiently hot and high yield electron distributions to create a superior bremsstrahlung x-ray source. An Omega experiment has been performed to investigate the optimization of SRS and high energy x-rays using Au hohlraums with parylene inner lining and foam fills, producing 10× greater x-ray yield at 50 keV than conventional direct drive experiments on the facility. Experiment and simulation details on this campaign will be presented. This work was performed under the auspices of the US DoE by LLNL under Contract No. DE-AC52-07NA27344.

  11. Statistics of “Cold” Early Impulsive Solar Flares in X-Ray and Microwave Domains

    Science.gov (United States)

    Lysenko, Alexandra L.; Altyntsev, Alexander T.; Meshalkina, Natalia S.; Zhdanov, Dmitriy; Fleishman, Gregory D.

    2018-04-01

    Solar flares often happen after a preflare/preheating phase, which is almost or entirely thermal. In contrast, there are the so-called early impulsive flares that do not show a (significant) preflare heating, but instead often show the Neupert effect—a relationship where the impulsive phase is followed by a gradual, cumulative-like, thermal response. This has been interpreted as a dominance of nonthermal energy release at the impulsive phase, even though a similar phenomenology is expected if the thermal and nonthermal energies are released in comparable amounts at the impulsive phase. Nevertheless, some flares do show a good quantitative correspondence between the nonthermal electron energy input and plasma heating; in such cases, the thermal response was weak, which results in them being called “cold” flares. We undertook a systematic search for such events among early impulsive flares registered by the Konus-Wind instrument in the triggered mode from 11/1994 to 4/2017, and selected 27 cold flares based on relationships between hard X-ray (HXR) (Konus-Wind) and soft X-ray (Geostationary Operational Environmental Satellite) emission. For these events, we put together all available microwave data from different instruments. We obtained temporal and spectral parameters of HXR and microwave emissions of the events and examined correlations between them. We found that, compared to a “mean” flare, the cold flares: (i) are weaker, shorter, and harder in the X-ray domain; (ii) are harder and shorter, but not weaker in the microwaves; (iii) have a significantly higher spectral peak frequencies in the microwaves. We discuss the possible physical reasons for these distinctions and implication of the finding.

  12. Discovery of Diffuse Hard X-ray Emission associated with Jupiter

    Science.gov (United States)

    Ezoe, Y.; Miyoshi, Y.; Ishikawa, K.; Ohashi, T.; Terada, N.; Uchiyama, Y.; Negoro, H.

    2009-12-01

    Our discovery of diffuse hard (1-5 keV) X-ray emission around Jupiter is reported. Recent Chandra and XMM-Newton observations revealed several types of X-rays in the vicinity of Jupiter such as auroral and disk emission from Jupiter and faint diffuse X-rays from the Io Plasma Torus (see Bhardwaj et al. 2007 for review). To investigate possible diffuse hard X-ray emission around Jupiter with the highest sensitivity, we conducted data analysis of Suzaku XIS observations of Jupiter on Feb 2006. After removing satellite and planetary orbital motions, we detected a significant diffuse X-ray emission extending to ~6 x 3 arcmin with the 1-5 keV X-ray luminosity of ~3e15 erg/s. The emitting region very well coincided with the Jupiter's radiation belts. The 1-5 keV X-ray spectrum was represented by a simple power law model with a photon index of 1.4. Such a flat continuum strongly suggests non-thermal origin. Although such an emission can be originated from multiple background point sources, its possibility is quite low. We hence examined three mechanisms, assuming that the emission is truly diffuse: bremsstrahlung by keV electrons, synchrotron emission by TeV electrons, and inverse Compton scattering of solar photons by MeV electrons. The former two can be rejected because of the X-ray spectral shape and implausible existence of TeV electrons around Jupiter, respectively. The last possibility was found to be possible because tens MeV electrons, which have been confirmed in inner radiation belts (Bolton et al. 2002), can kick solar photons to the keV energy range and provide a simple power-law continuum. We estimated an average electron density from the X-ray luminosity assuming the oblate spheroid shaped emitting region with 8 x 8 x 4 Jovian radii. The necessary density was 0.02 1/cm3 for 50 MeV electrons. Hence, our results may suggest a new particle acceleration phenomenon around Jupiter.

  13. Assessment of image quality in x-ray radiography imaging using a small plasma focus device

    International Nuclear Information System (INIS)

    Kanani, A.; Shirani, B.; Jabbari, I.; Mokhtari, J.

    2014-01-01

    This paper offers a comprehensive investigation of image quality parameters for a small plasma focus as a pulsed hard x-ray source for radiography applications. A set of images were captured from some metal objects and electronic circuits using a low energy plasma focus at different voltages of capacitor bank and different pressures of argon gas. The x-ray source focal spot of this device was obtained to be about 0.6 mm using the penumbra imaging method. The image quality was studied by several parameters such as image contrast, line spread function (LSF) and modulation transfer function (MTF). Results showed that the contrast changes by variations in gas pressure. The best contrast was obtained at a pressure of 0.5 mbar and 3.75 kJ stored energy. The results of x-ray dose from the device showed that about 0.6 mGy is sufficient to obtain acceptable images on the film. The measurements of LSF and MTF parameters were carried out by means of a thin stainless steel wire 0.8 mm in diameter and the cut-off frequency was obtained to be about 1.5 cycles/mm. - Highlights: • We investigated a small plasma focus as pulsed x-ray source for radiography applications. • The image quality was studied by several parameters such as image contrast, LSF and MTF. • The x-ray source focal spot was obtained to be ∼0.6 mm using the penumbra imaging method. • The x-ray dose measurement showed that about 0.6 mGy is sufficient to obtain acceptable images on the film. • The profiles of LSF and MTF showed that the cut-off frequency is about 1.5 cycles/mm

  14. Laser interaction with matter as a source of U.V. and soft X-ray radiation: application to X-ray cinematography

    International Nuclear Information System (INIS)

    Tonon, G.F.; Colombant, Denis; Delmare, Claude; Rabeau, Maxime

    A new detecting device is described. It allows one to get the frequency, the time and space resolution of pictures of U.V. and soft X ray emission of a laser created plasma in a single shot: X ray pictures of such a plasma are presented. After these preliminary results, it is possible to set up readily an X ray framing camera. A laser created plasma is an X ray source of special interest: the emitted power can be 10% of the laser intensity and the emitted spectrum is centered around 1A wavelength [fr

  15. Effect of inserted metal at anode tip on formation of pulsed X-ray emitting zone of plasma focus device

    Science.gov (United States)

    Miremad, Seyed Milad; Shirani Bidabadi, Babak

    2018-04-01

    The effect of the anode's insert material of a plasma focus device on the properties of X-ray emission zone was studied. Inserts were fabricated out of six different materials including aluminum, copper, zinc, tin, tungsten, and lead to cover a wide range of atomic numbers. For each anode's insert material at different gas pressures and different voltages, the shape of X-ray emission zone was recorded by three pinhole cameras, which were installed on sidewall and roof of the chamber of plasma focus device. The results indicated that by changing the gas pressure and the charge voltage of capacitor, the X-ray source of plasma focus emerges with different forms as a concentrated column or conical shape with sharp or cloudy edges. These structures are in the form of a combination of plasma emission and anode-tip emission with different intensities. These observations indicate that the material of the anode-tip especially affects the structure of X-ray emission zone.

  16. Coronal temperature diagnostics from high-resolution soft X-ray spectra

    Science.gov (United States)

    Strong, K. T.; Claflin, E. S.; Lemen, J. R.; Linford, G. A.

    1988-01-01

    The problem of deriving the temperature of the coronal plasma from soft X-ray spectra is discussed. Spectral atlas scans of the soft X-ray spectrum from the Flat Crystal Spectrometer on the Solar Maximum Mission are compared with theoretical predictions of the relative intensities of some of the brighter lines to determine which line intensity ratios give the most reliable temperature diagnostics. The techniques considered include line widths, He-like G ratios, intensity ratios, and ratios of lines formed by different elements. It is found that the best temperature diagnostics come from the ratios of lines formed by successive ionization stages of the same element.

  17. Electromagnetic diagnostics of ECR-Ion Sources plasmas: optical/X-ray imaging and spectroscopy

    Science.gov (United States)

    Mascali, D.; Castro, G.; Altana, C.; Caliri, C.; Mazzaglia, M.; Romano, F. P.; Leone, F.; Musumarra, A.; Naselli, E.; Reitano, R.; Torrisi, G.; Celona, L.; Cosentino, L. G.; Giarrusso, M.; Gammino, S.

    2017-12-01

    Magnetoplasmas in ECR-Ion Sources are excited from gaseous elements or vapours by microwaves in the range 2.45-28 GHz via Electron Cyclotron Resonance. A B-minimum, magnetohydrodynamic stable configuration is used for trapping the plasma. The values of plasma density, temperature and confinement times are typically ne= 1011-1013 cm-3, 01 eVSilicon Drift detectors with high energy resolution of 125 eV at 5.9 keV have been used for the characterization of plasma emission at 02X-ray pin-hole camera technique has allowed space resolved X-ray spectroscopy with a spatial resolution down to 30 μm and an energy resolution down to 140 eV at 5.9 keV . In parallel, imaging in the optical range and spectroscopic measurements have been carried out. Relative abundances of H/H2 atoms/molecules in the plasmas have been measured for different values of neutral pressure, microwave power and magnetic field profile (they are critical for high-power proton sources).

  18. Solar cycle variation of cosmic ray intensity along with interplanetary and solar wind plasma parameters

    International Nuclear Information System (INIS)

    Mishra, R.K.; Tiwari, S.; Agarwal, R.

    2008-01-01

    Galactic cosmic rays are modulated at their propagation in the heliosphere by the effect of the large-scale structure of the interplanetary medium. A comparison of the variations in the cosmic ray intensity data obtained by neutron monitoring stations with those in geomagnetic disturbance, solar wind velocity (V), interplanetary magnetic field (B), and their product (V , B) near the Earth for the period 1964-2004 has been presented so as to establish a possible correlation between them. We used the hourly averaged cosmic ray counts observed with the neutron monitor in Moscow. It is noteworthy that a significant negative correlation has been observed between the interplanetary magnetic field, product (V , B) and cosmic ray intensity during the solar cycles 21 and 22. The solar wind velocity has a good positive correlation with cosmic ray intensity during solar cycle 21, whereas it shows a weak correlation during cycles 20, 22 and 23. The interplanetary magnetic field shows a weak negative correlation with cosmic rays for solar cycle 20, and a good anti-correlation for solar cycles 21-23 with the cosmic ray intensity, which, in turn, shows a good positive correlation with disturbance time index (Dst) during solar cycles 21 and 22, and a weak correlation for cycles 20 and 23. (Authors)

  19. Remote planetary geochemical exploration with the NEAR X-ray/gamma-ray spectrometer

    International Nuclear Information System (INIS)

    Trombka, J.I.; Boynton, W.V.; Brueckner, J.; Squyres, S.; Clark, P.E.; Starr, R.; Evans, L.G.; Floyd, S.R.; McClanahan, T.P.; Goldsten, J.; Mcnutt, R.; Schweitzer, J.S.

    1999-01-01

    The X-ray/gamma-ray spectrometer (XGRS) instrument onboard the Near Earth Asteroid Rendezvous (NEAR) spacecraft will map asteroid 433 Eros in the 0.2 keV to 10 MeV energy region. Measurements of the discrete line X-ray and gamma-ray emissions in this energy domain can be used to obtain both qualitative and quantitative elemental composition maps of the asteroid surface. The NEAR X-ray/gamma-ray spectrometer (XGRS) was turned on for the first time during the week of 7 April 1996. Rendezvous with Eros 433 is expected during December 1998. Observations of solar X-ray spectra during both quiescent and active periods have been made. A gamma-ray transient detection system has been implemented and about three gamma-ray transient events a week have been observed which are associated with either gamma-ray bursts or solar flares

  20. Low Energy X-Ray and Electron Physics and Technology for High-Temperature Plasma Diagnostics

    Science.gov (United States)

    1987-10-01

    cransmission band for Che rejeccion of such background radiacions around Che 500-1000 eV region by combining as a primary monochromator a 300 ßg...X-Radiations of the Solar Corona," Technical Report No. 7, 1-413, AFOSR 66-2446 (September 1966). 30. "X-Ray Absorption in the 2 to

  1. X-ray structural analysis of plasma sprayed europium oxide

    Energy Technology Data Exchange (ETDEWEB)

    Gorshkov, B.N.; Loskutov, V.S.; Gavrish, A.A.; Shakh, G.E.

    1981-12-01

    An X-ray structure microanalysis is made for europium oxide powder produced by sintering and plasmic spheroidization for plasma spraying. The technique of concern is shown not to alter chemical composition of the powder. It is stated that a rise in the plasma jet enthalpy while spraying does not result in dissociation of europium oxide and its interaction with the plasma flux. The coating (to 15.2 kWxs/g) is found to have only a high-temperature (monoclinic) europium oxide phase and there appears a low-temperature (cubic) phase with a subsequent increase in the enthalpy. The plasma jet enthalpy increasing the grain size and the crystal lattice c parameter of the sprayed europium oxide are shown to decrease; the a parameter reduces with an enthalpy growth to 16.2 kW s/g and then smoothly increases with the enthalpy further growth. It is noticed that the europium oxide coating does not interact with an aluminium D16 alloy substrate.

  2. Influence of O2 plasma treatment on NiO x layer in perovskite solar cells

    Science.gov (United States)

    Nishihara, Yoshihiko; Chikamatsu, Masayuki; Kazaoui, Said; Miyadera, Tetsuhiko; Yoshida, Yuji

    2018-04-01

    We fabricated perovskite solar cells (PSCs) with an inverted p-i-n planar structure using a NiO x film as a hole-transporting layer. Since the surface of the NiO x film fabricated by sputtering is hydrophobic, O2 plasma treatment under various conditions was performed to improve its wettability. Water contact angles after the treatment under both normal and weak conditions on the NiO x film reached approximately 15°. After the treatment, the valence band level of the NiO x film was deeper by about 0.15 eV. The maximum efficiency of the NiO x -based device under the optimized O2 plasma condition reached 12.3%.

  3. Detectability of Sungrazing Comet Soft X-ray Irradiance

    Directory of Open Access Journals (Sweden)

    Su Yeon Oh

    2007-12-01

    Full Text Available Originating from the Oort cloud, some comets disappear to impact against the Sun or to split up by strong gravitational force. Then they don't go back to the Oort cloud. They are called sungrazing comets. The comets are detected by sublimation of ices and ejection of gas and dust through solar heat close to the Sun. There exists the charge transfer from heavy ions in the solar wind to neutral atoms in the cometary atmosphere by interaction with the solar wind. Cometary atoms would be excited to high electronic levels and their de-excitation would result in X-ray emission, or it would be scattering of solar X-ray emission by very small cometary grains. We calculated the X-ray emission applying the model suggested by Mendis & Flammer (1984 and Cravens (1997. In our estimation, the sungrazing comet whose nucleus size is about 1 km in radius might be detectable within a distance of 3 solar radius from the sun on soft X-ray solar camera.

  4. Conceptual design of the tomographic system for simultaneous studying of soft and hard X-ray emission from dense magnetized plasma

    Energy Technology Data Exchange (ETDEWEB)

    Bielecki, J., E-mail: jakub.bielecki@ifj.edu.edu; Wójcik-Gargula, A.; Scholz, M.

    2016-11-15

    The article presents a new approach for investigation of spatial distributions of soft and hard X-rays emitted from dense magnetized plasma. The approach is based on the application of tomographic methods to the X-ray emission reconstruction in a plasma focus (PF) device. Quantitative investigation of the anisotropy of the reconstructed X–ray plasma emissivity may help to explain the nature of fusion reaction mechanisms in a PF device. The aim of this work is to present a conceptual design of a novel dual-energy X-ray emission tomographic system dedicated to the PF-24 plasma focus device. The system, which enables the simultaneous registration of soft and hard X-rays, is composed of three X‐ray pinhole cameras. Each camera is equipped with a pair of 16-element Si photodiode arrays arranged in two layers separated by an aluminum attenuator. The Geant4 code was used to optimize the layout and parameters of the applied detectors. In addition, a method of tomographic reconstruction from a sparse data set provided by the experimental setup has been presented.

  5. The normalization of solar X-ray data from many experiments.

    Science.gov (United States)

    Wende, C. D.

    1972-01-01

    A conversion factor is used to convert Geiger (GM) tube count rates or ion chamber currents into units of the incident X-ray energy flux in a specified passband. A method is described which varies the passband to optimize these conversion factors such that they are relatively independent of the spectrum of the incident photons. This method was applied to GM tubes flown on Explorers 33 and 35 and Mariner 5 and to ion chambers flown on OSO 3 and OGO 4. Revised conversion factors and passbands are presented, and the resulting absolute solar X-ray fluxes based on these are shown to improve the agreement between the various experiments. Calculations have shown that, although the GM tubes on Explorer 33 viewed the Sun off-axis, the effective passband did not change appreciably, and the simple normalization of the count rates to the count rates of a similar GM tube on Explorer 35 was justified.

  6. Polarization of X rays of multiply charged ions in dense high-temperature plasma

    NARCIS (Netherlands)

    Baronova, EO; Dolgov, AN; Yakubovskii, LK

    2004-01-01

    The development of a method for studying the features of X-ray emission by multiply charged ions in a dense hot plasma is considered. These features are determined by the radiation polarization phenomenon.

  7. X-ray emission spectroscopy of well-characterised non-LTE plasmas

    International Nuclear Information System (INIS)

    Bourgaux, A C; Bastiani-Ceccotti, S; Audebert, P; Marquès, J R; Vassura, L; Vinci, T; Jacquemot, S; Dorchies, F; Leguay, P M; Chung, H K; Bowen, C; Dervieux, V; Renaudin, P; Silvert, V

    2016-01-01

    This paper will present an experimental platform developed on LULI2000 to measure x-ray emission of non-LTE plasmas in well-defined hydrodynamic conditions thanks to implementation of a whole set of diagnostics, including time-resolved electronic and ionic Thomson scattering and self-optical pyrometry. K-, L- and M-shell spectra will be presented and the methodology, that has been developed to analyze them, discussed. (paper)

  8. Study of laser-imploded core plasmas with an advanced Kirkpatrick endash Baez x-ray microscope

    International Nuclear Information System (INIS)

    Kodama, R.; Shiraga, H.; Miyanaga, M.; Matsushita, T.; Nakai, M.; Azechi, H.; Mima, K.; Kato, Y.

    1997-01-01

    We developed an advanced Kirkpatrick endash Baez (AKB) x-ray microscope which consisted of two hyperbolic mirrors and two elliptic mirrors. The spatial resolution of approx-lt 3 μm was realized over ∼1 mm diam. This AKB microscope was used for x-ray imaging in laser fusion experiments. Laser absorption nonuniformity with a large wave number on a spherical solid target or a plane slab target was estimated by measurements of x-ray emission from the target surface with the microscope. The x-ray images of the imploded core plasmas were also obtained with the AKB microscope, changing the laser focus condition and the laser energy balance. copyright 1997 American Institute of Physics

  9. Development of a compact laser-produced plasma soft X-ray source for radiobiology experiments

    Czech Academy of Sciences Publication Activity Database

    Adjei, D.; Ayele, M. G.; Wachulak, P.; Bartnik, A.; Wegrzynski, L.; Fiedorowicz, H.; Vyšín, Luděk; Wiechec, A.; Lekki, J.; Kwiatek, W. M.; Pina, L.; Davídková, Marie; Juha, Libor

    2015-01-01

    Roč. 364, Dec (2015), s. 27-32 ISSN 0168-583X R&D Projects: GA ČR(CZ) GBP108/12/G108; GA ČR GA13-28721S EU Projects: European Commission(XE) 284464 - LASERLAB-EUROPE Institutional support: RVO:68378271 ; RVO:61389005 Keywords : laser-produced plasma * soft X-rays * radiobiology * gas puff target * water window Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.389, year: 2015

  10. Scintillator power meter applied on Z-pinch plasma soft X-ray yield measurement

    International Nuclear Information System (INIS)

    Zhang Siqun; Huang Xianbin; Li Jing; Dan Jiakun; Li Jun; Yang Libing; Cui Mingqi; Zhao Yidong

    2010-01-01

    This paper presents the configuration and measuring parameters of scintillator power meter applied in Z-pinch plasma soft X-ray yield measurement on Yang accelerator. It also introduces the calibration experiment on BSRF, and analyzes the defect of the power meter from calibration results, the possible errors and feasible method for correcting the errors. The measuring results are revised according to spectrum acquired from Dante spectrometer. The revised discrepancy of two instruments is decreased from over 30% to subter-15%. Finally, the result of yield measurement of the puff Z-pinch X-ray radiation is reported as well, i.e., hundreds of Joule, multigigawatt levels of soft X ray radiation were produced by puff Z-pinch on Yang accelerator. (authors)

  11. The EVE plus RHESSI DEM for Solar Flares, and Implications for Residual Non-Thermal X-Ray Emission

    Science.gov (United States)

    McTiernan, James; Caspi, Amir; Warren, Harry

    2016-05-01

    Solar flare spectra are typically dominated by thermal emission in the soft X-ray energy range. The low energy extent of non-thermal emission can only be loosely quantified using currently available X-ray data. To address this issue, we combine observations from the EUV Variability Experiment (EVE) on-board the Solar Dynamics Observatory (SDO) with X-ray data from the Reuven Ramaty High Energy Spectroscopic Imager (RHESSI) to calculate the Differential Emission Measure (DEM) for solar flares. This improvement over the isothermal approximation helps to resolve the ambiguity in the range where the thermal and non-thermal components may have similar photon fluxes. This "crossover" range can extend up to 30 keV.Previous work (Caspi et.al. 2014ApJ...788L..31C) concentrated on obtaining DEM models that fit both instruments' observations well. For this current project we are interested in breaks and cutoffs in the "residual" non-thermal spectrum; i.e., the RHESSI spectrum that is left over after the DEM has accounted for the bulk of the soft X-ray emission. As in our earlier work, thermal emission is modeled using a DEM that is parametrized as multiple gaussians in temperature. Non-thermal emission is modeled as a photon spectrum obtained using a thin-target emission model ('thin2' from the SolarSoft Xray IDL package). Spectra for both instruments are fit simultaneously in a self-consistent manner.For this study, we have examined the DEM and non-thermal resuidual emission for a sample of relatively large (GOES M class and above) solar flares observed from 2011 to 2014. The results for the DEM and non-thermal parameters found using the combined EVE-RHESSI data are compared with those found using only RHESSI data.

  12. Absorption of aluminium X-ray lines in a laser created gold plasma

    International Nuclear Information System (INIS)

    Combis, P.; Busquet, M.; Louis-Jacquet, M.

    1986-04-01

    We have studied the absorption of aluminium X-ray lines through a gold plasma by focusing a high intensity laser-beam onto a specific target. Absorption in the wavelength range of 5 to 7 A has been evidenced and measured for Aluminium resonance lines

  13. UV and X-ray Evolution of AR12230 as Observed with IRIS and FOXSI-II

    Science.gov (United States)

    Ryan, Daniel; Christe, Steven; Glesener, Lindsay; Vievering, Julie; Krucker, Sam; Ishikawa, Shin-Nosuke

    2017-08-01

    We present a multi-spectral and spatio-temporal analysis of AR12230 using both UV and X-ray spectroscopic imaging obtained as part of a coordinated observing campaign on 11 December 2014. The campaign involved IRIS (Interface Region Imaging Spectrometer) -- which provides both UV imaging and slit spectrograph observations of optically thick chromospheric and transition region emission -- and FOXSI-II (Focusing Optics X-ray Solar Imager) -- the second in a series of sounding rocket flights which combines grazing incidence direct focusing optics to produce solar X-ray spectroscopic imaging in the range 4-15keV. The active region exhibits a prolonged compact brightening in the IRIS 1330 A and 1400 A slit-jaw channels near the center of the active region throughout the duration of the observations. In the early phase of the observations FOXSI-II shows an X-ray source approximately 20x20 arcsec centered at the same location. The X-ray spectra show the presence of hot (~8 MK) thermal plasma and is suggestive of the presence of non-thermal electrons.. Later, two additional transient, spatially extended, simultaneous brightenings are observed, one of which was captured by the IRIS slit spectrograph. We combine these observations to explore the evolution and topology of the active region. Hydrodynamic modeling of the chromosphere is used to place a limit on the amount of non-thermal electrons required to produce the observed UV emission. This result is then compared to the limit inferred from the FOXSI-II X-ray spectra. Thus, we explore the role of non-thermal electrons and hydrodynamics in the energization and evolution of plasma in active regions.

  14. Design calculations for a xenon plasma x-ray shield to protect the NIF optical Thomson scattering diagnostic.

    Science.gov (United States)

    Swadling, G F; Ross, J S; Datte, P; Moody, J; Divol, L; Jones, O; Landen, O

    2016-11-01

    An Optical Thomson Scattering (OTS) diagnostic is currently being developed for the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory. This diagnostic is designed to make measurements of the hohlraum plasma parameters, such as the electron temperature and the density, during inertial confinement fusion (ICF) experiments. NIF ICF experiments present a very challenging environment for optical measurements; by their very nature, hohlraums produce intense soft x-ray emission, which can cause "blanking" (radiation induced opacity) of the radiation facing optical components. The soft x-ray fluence at the surface of the OTS blast shield, 60 cm from the hohlraum, is estimated to be ∼8 J cm -2 . This is significantly above the expected threshold for the onset of "blanking" effects. A novel xenon plasma x-ray shield is proposed to protect the blast shield from x-rays and mitigate "blanking." Estimates suggest that an areal density of 10 19 cm -2 Xe atoms will be sufficient to absorb 99.5% of the soft x-ray flux. Two potential designs for this shield are presented.

  15. X-ray spectroscopic technique for energetic electron transport studies in short-pulse laser/plasma interactions

    Energy Technology Data Exchange (ETDEWEB)

    Tutt, T.E.

    1994-12-01

    When a solid target is irradiated by a laser beam, the material is locally heated to a high temperature and a plasma forms. The interaction of the laser with plasma can produce energetic electrons. By observing the behavior of these {open_quotes}hot{close_quotes} electrons, we hope to obtain a better understanding of Laser/Plasma Interactions. In this work we employ a layered-fluorescer technique to study the transport, and therefore the energetics, of the electrons. The plasma forms on a thin foil of metallic Pd which is bonded to thin layer of metallic Sn. Electrons formed from the plasma penetrate first the Pd and then the Sn. In both layers the energetic electrons promote inner (K) shell ionization of the metallic atoms which leads to the emission of characteristic K{sub {alpha}} x-rays of the fluorescers. By recording the x-ray spectrum emitted by the two foils, we can estimate the energy-dependent range of the electrons and their numbers.

  16. Purification and preliminary X-ray crystallographic studies of β-microseminoprotein from human seminal plasma

    International Nuclear Information System (INIS)

    Kumar, Vijay; Roske, Yvette; Singh, Nagendra; Heinemann, Udo; Singh, Tej P.; Yadav, Savita

    2009-01-01

    The preliminary X-ray data of β-microseminoprotein isolated from human seminal plasma at 2.4 Å resolution are reported. β-Microseminoprotein (β-MSP) is a small cysteine-rich protein with a molecular mass of 10 kDa. It was first isolated from human seminal plasma and has subsequently been identified from several species. Comparison of the amino-acid sequences of β-MSP proteins suggests that the protein is a rapidly evolving protein. The function of β-MSP is poorly understood. Furthermore, no crystal structure has been reported of any β-MSP; therefore, determination of the crystal structure of β-MSP is the foremost task in order to understand the function of this protein completely. Here, the purification, crystallization and preliminary X-ray diffraction analysis of β-MSP from human seminal plasma are described. The protein was purified using anion-exchange and size-exclusion chromatography and the purified protein was crystallized using 0.1 M ammonium sulfate, 0.1 M HEPES buffer pH 7.0 and 20%(w/v) PEG 3350. The crystals belonged to the tetragonal space group P4 3 22 and contained three β-MSP molecules in the asymmetric unit. X-ray intensity data were collected to 2.4 Å resolution

  17. Solar Chameleons

    CERN Document Server

    Brax, Philippe

    2010-01-01

    We analyse the creation of chameleons deep inside the sun and their subsequent conversion to photons near the magnetised surface of the sun. We find that the spectrum of the regenerated photons lies in the soft X-ray region, hence addressing the solar corona problem. Moreover, these back-converted photons originating from chameleons have an intrinsic difference with regenerated photons from axions: their relative polarisations are mutually orthogonal before Compton interacting with the surrounding plasma. Depending on the photon-chameleon coupling and working in the strong coupling regime of the chameleons to matter, we find that the induced photon flux, when regenerated resonantly with the surrounding plasma, coincides with the solar flux within the soft X-ray energy range. Moreover, using the soft X-ray solar flux as a prior, we find that with a strong enough photon-chameleon coupling the chameleons emitted by the sun could lead to a regenerated photon flux in the CAST pipes, which could be within the reach...

  18. Non-thermal electron populations in microwave heated plasmas investigated with X-ray detectors

    Energy Technology Data Exchange (ETDEWEB)

    Belapure, Jaydeep Sanjay

    2013-04-15

    An investigation of the generation and dynamics of superthermal electrons in fusion plasma is carried out. A SDD+CsI(Tl) based X-ray diagnostic is constructed, characterized and installed at ASDEX Upgrade. In various plasma heating power and densities, the fraction and the energy distribution of the superthermal electrons is obtained by a bi-Maxwellian model and compared with Fokker-Planck simulations.

  19. A Novel Spectrometer for Measuring Laser-Produced Plasma X-Ray in Inertial Confinement Fusion

    Directory of Open Access Journals (Sweden)

    Zhu Gang

    2012-01-01

    Full Text Available In the experimental investigations of inertial confinement fusion, the laser-produced high-temperature plasma contains very abundant information, such as the electron temperature and density, ionization. In order to diagnose laser-plasma distribution in space and evolution in time, an elliptical curved crystal spectrometer has been developed and applied to diagnose X-ray of laser-produced plasma in 0.2~2.46 nm region. According to the theory of Bragg diffraction, four kinds of crystal including LiF, PET, MiCa, and KAP were chosen as dispersive elements. The distance of crystal lattice varies from 0.4 to 2.6 nm. Bragg angle is in the range of 30°~67.5°, and the spectral detection angle is in 55.4°~134°. The curved crystal spectrometer mainly consists of elliptical curved crystal analyzer, vacuum configuration, aligning device, spectral detectors and three-dimensional microadjustment devices. The spectrographic experiment was carried out on the XG-2 laser facility. Emission spectrum of Al plasmas, Ti plasma, and Au plasmas have been successfully recorded by using X-ray CCD camera. It is demonstrated experimentally that the measured wavelength is accorded with the theoretical value.

  20. Principal component analysis of solar flares in the soft X-ray flux

    International Nuclear Information System (INIS)

    Teuber, D.L.; Reichmann, E.J.; Wilson, R.M.; National Aeronautics and Space Administration, Huntsville, AL

    1979-01-01

    Principal component analysis is a technique for extracting the salient features from a mass of data. It applies, in particular, to the analysis of nonstationary ensembles. Computational schemes for this task require the evaluation of eigenvalues of matrices. We have used EISPACK Matrix Eigen System Routines on an IBM 360-75 to analyze full-disk proportional-counter data from the X-ray event analyzer (X-REA) which was part of the Skylab ATM/S-056 experiment. Empirical orthogonal functions have been derived for events in the soft X-ray spectrum between 2.5 and 20 A during different time frames between June 1973 and January 1974. Results indicate that approximately 90% of the cumulative power of each analyzed flare is contained in the largest eigenvector. The first two largest eigenvectors are sufficient for an empirical curve-fit through the raw data and a characterization of solar flares in the soft X-ray flux. Power spectra of the two largest eigenvectors reveal a previously reported periodicity of approximately 5 min. Similar signatures were also obtained from flares that are synchronized on maximum pulse-height when subjected to a principal component analysis. (orig.)

  1. X-Ray Lasers 2016

    CERN Document Server

    Bulanov, Sergei; Daido, Hiroyuki; Kato, Yoshiaki

    2018-01-01

    These proceedings comprise a selection of invited and contributed papers presented at the 15th International Conference on X-Ray Lasers (ICXRL 2016), held at the Nara Kasugano International Forum, Japan, from May 22 to 27, 2016. This conference was part of an ongoing series dedicated to recent developments in the science and technology of x-ray lasers and other coherent x-ray sources with additional focus on supporting technologies, instrumentation and applications.   The book showcases recent advances in the generation of intense, coherent x-rays, the development of practical devices and their applications across a wide variety of fields. It also discusses emerging topics such as plasma-based x-ray lasers, 4th generation accelerator-based sources and higher harmonic generations, as well as other x-ray generation schemes.

  2. Soft x-ray measurements in the FN-II dense plasma focus device for different anode configurations

    International Nuclear Information System (INIS)

    Rojo-Blanco, C; Castillo-Mejía, F; Rangel-Gutiérrez, J; Herrera-Velázquez, J J E

    2012-01-01

    A study of the soft x-ray emission is presented, for a low energy (4.8 kJ) dense plasma focus device. Three Quantrad Si PIN-diodes with differential filter combinations of Be, Al, Ti, Ni, and Mo are employed as time-resolved x-ray detectors. The x-ray flux in different energy windows is measured as function of the deuterium filling pressure. A comparison is made for three anode configurations: (a) hollow, (b) flat, and (c) 2mm diameter W needle.

  3. The Soft X-ray Spectrophotometer SphinX for the CORONAS-Photon Mission

    Science.gov (United States)

    Sylwester, Janusz; Kowalinski, Miroslaw; Szymon, Gburek; Bakala, Jaroslaw; Kuzin, Sergey; Kotov, Yury; Farnik, Frantisek; Reale, Fabio

    The purpose, construction details and calibration results of the new design, Polish-led solar X-ray spectrophotometer SphinX will be presented. The instrument constitutes a part of the Russian TESIS X-ray and EUV complex aboard the forthcoming CORONAS-Photon solar mission to be launched later in 2008. SphinX uses Si-PIN detectors for high time resolution (down to 0.01 s) measurements of solar spectra in the energy range between 0.5 keV and 15 keV. The spectral resolution allows separating 256 individual energy channels in this range with particular groups of lines clearly distinguishable. Unprecedented accuracy of the instrument calibration at the XACT (Palermo) and BESSY (Berlin) synchrotron will allow for establishing the solar soft X-ray photometric reference system. The cross-comparison between SphinX and the other instruments presently in orbit like XRT on Hinode, RHESSI and GOES X-ray monitor, will allow for a precise determination of the coronal emission measure and temperature during both very low and very high activity periods. Examples of the detectors' ground calibration results as well as the calculated synthetic spectra will be presented. The operation of the instrument while in orbit will be discussed allowing for suggestions from other groups to be still included in mission planning.

  4. Direct electron acceleration in plasma waveguides for compact high-repetition-rate x-ray sources

    International Nuclear Information System (INIS)

    Lin, M-W; Jovanovic, I

    2014-01-01

    Numerous applications in fundamental and applied research, security, and industry require robust, compact sources of x-rays, with a particular recent interest in monochromatic, spatially coherent, and ultrafast x-ray pulses in well-collimated beams. Such x-ray sources usually require production of high-quality electron beams from compact accelerators. Guiding a radially polarized laser pulse in a plasma waveguide has been proposed for realizing direct laser acceleration (DLA), where the electrons are accelerated by the axial electric field of a co-propagating laser pulse (Serafim et al 2000 IEEE Trans. Plasma Sci. 28 1190). A moderate laser peak power is required for DLA when compared to laser wakefield acceleration, thus offering the prospect for high repetition rate operation. By using a density-modulated plasma waveguide for DLA, the acceleration distance can be extended with pulse guiding, while the density-modulation with proper axial structure can realize the quasi-phase matching between the laser pulses and electrons for a net gain accumulation (York et al 2008 Phys. Rev. Lett. 100 195001; York et al 2008 J. Opt. Soc. Am. B 25 B137; Palastro et al 2008 Phys. Rev. E 77 036405). We describe the development and application of a test particle model and particle-in-cell model for DLA. Experimental setups designed for fabrication of optically tailored plasma waveguides via the ignitor-heater scheme, and for generation and characterization of radially polarized short pulses used to drive DLA, are presented. (paper)

  5. The size of coronal hard X-ray sources in solar flares: How big are they?

    Science.gov (United States)

    Effenberger, F.; Krucker, S.; Rubio da Costa, F.

    2017-12-01

    Coronal hard X-ray sources are considered to be one of the key signatures of non-thermal particle acceleration and heating during the energy release in solar flares. In some cases, X-ray observations reveal multiple components spatially located near and above the loop top and even further up in the corona. Here, we combine a detailed RHESSI imaging analysis of near-limb solar flares with occulted footpoints and a multi-wavelength study of the flare loop evolution in SDO/AIA. We connect our findings to different current sheet formation and magnetic break-out scenarios and relate it to particle acceleration theory. We find that the upper and usually fainter emission regions can be underestimated in their size due to the majority of flux originating from the lower loops.

  6. Katherine E. Weimer Award: X-ray light sources from laser-plasma and laser-electron interaction: development and applications

    Science.gov (United States)

    Albert, Felicie

    2017-10-01

    Bright sources of x-rays, such as synchrotrons and x-ray free electron lasers (XFEL) are transformational tools for many fields of science. They are used for biology, material science, medicine, or industry. Such sources rely on conventional particle accelerators, where electrons are accelerated to gigaelectronvolts (GeV) energies. The accelerated particles are wiggled in magnetic structures to emit x-ray radiation that is commonly used for molecular crystallography, fluorescence studies, chemical analysis, medical imaging, and many other applications. One of the drawbacks of these machines is their size and cost, because electric field gradients are limited to about 100 V/M in conventional accelerators. Particle acceleration in laser-driven plasmas is an alternative to generate x-rays via betatron emission, Compton scattering, or bremsstrahlung. A plasma can sustain electrical fields many orders of magnitude higher than that in conventional radiofrequency accelerator structures. When short, intense laser pulses are focused into a gas, it produces electron plasma waves in which electrons can be trapped and accelerated to GeV energies. X-ray sources, driven by electrons from laser-wakefield acceleration, have unique properties that are analogous to synchrotron radiation, with a 1000-fold shorter pulse. An important use of x-rays from laser plasma accelerators is in High Energy Density (HED) science, which requires laser and XFEL facilities to create in the laboratory extreme conditions of temperatures and pressures that are usually found in the interiors of stars and planets. To diagnose such extreme states of matter, the development of efficient, versatile and fast (sub-picosecond scale) x-ray probes has become essential. In these experiments, x-ray photons can pass through dense material, and absorption of the x-rays can be directly measured, via spectroscopy or imaging, to inform scientists about the temperature and density of the targets being studied. Performed

  7. Effects of plasma radiation on wound healing compared with X-ray

    Energy Technology Data Exchange (ETDEWEB)

    Azorin V, E.; Pena E, R. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Azorin V, J. C., E-mail: erica.azorin@inin.gob.mx [Universidad de Guanajuato, Campus Leon, Departamento de Ingenieria Fisica, Blvd. Prol. Calz. de los Heroes No. 908, Col. La Martinica, Leon, Guanajuato (Mexico)

    2015-10-15

    Full text: The radiation emitted by the plasma needle has shown high efficiency in the inactivation of microorganisms and the acceleration of the healing process; apparently such effects are related to the antioxidant activity, induction of cell damage and the generation of free radicals. To take advantage of plasma clinical applications it is essential to understand the cellular mechanisms activated by the exposure of human cells to radiation emitted by cold plasma. In this work we present the results of the characterization of the responses of human skin fibroblasts exposed to the radiation emitted by a plasma by varying the magnitude of flow, electrical power, time and composition of the cell culture medium comparing it with the response of these fibroblasts to low energy X-rays. (Author)

  8. Effects of plasma radiation on wound healing compared with X-ray

    International Nuclear Information System (INIS)

    Azorin V, E.; Pena E, R.; Azorin V, J. C.

    2015-10-01

    Full text: The radiation emitted by the plasma needle has shown high efficiency in the inactivation of microorganisms and the acceleration of the healing process; apparently such effects are related to the antioxidant activity, induction of cell damage and the generation of free radicals. To take advantage of plasma clinical applications it is essential to understand the cellular mechanisms activated by the exposure of human cells to radiation emitted by cold plasma. In this work we present the results of the characterization of the responses of human skin fibroblasts exposed to the radiation emitted by a plasma by varying the magnitude of flow, electrical power, time and composition of the cell culture medium comparing it with the response of these fibroblasts to low energy X-rays. (Author)

  9. Specific features of thermocouple calorimeter application for measurements of pulsed X-ray emission from plasma

    International Nuclear Information System (INIS)

    Gavrilov, V. V.; Fasakhov, I. K.

    2012-01-01

    It is shown that the accuracy of time-integrated measurements of pulsed X-ray emission from hot plasma with calibrated thermocouple calorimeters is mainly determined by two factors. The first and the most important factor is heating of the filter by the absorbed X-rays; as a result, the calorimeter measures the thermal radiation of the filter, which causes appreciable distortion of the temporal profile and amplitude of the recorded signal. The second factor is the dependence of the effective depth of X-ray absorption in the dielectric that covers the entrance window of the calorimeter on the energy of X-ray photons, i.e., on the recorded radiation spectrum. The results of model calculations of the calorimeter signal are compared with the experimental data.

  10. Ultrashort X-ray pulse science

    Energy Technology Data Exchange (ETDEWEB)

    Chin, Alan Hap [Univ. of California, Berkeley, CA (US). Dept. of Physics; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    1998-05-01

    A variety of phenomena involves atomic motion on the femtosecond time-scale. These phenomena have been studied using ultrashort optical pulses, which indirectly probe atomic positions through changes in optical properties. Because x-rays can more directly probe atomic positions, ultrashort x-ray pulses are better suited for the study of ultrafast structural dynamics. One approach towards generating ultrashort x-ray pulses is by 90° Thomson scattering between terawatt laser pulses and relativistic electrons. Using this technique, the author generated ~ 300 fs, 30 keV (0.4 Å) x-ray pulses. These x-ray pulses are absolutely synchronized with ultrashort laser pulses, allowing femtosecond optical pump/x-ray probe experiments to be performed. Using the right-angle Thomson scattering x-ray source, the author performed time-resolved x-ray diffraction studies of laser-perturbated InSb. These experiments revealed a delayed onset of lattice expansion. This delay is due to the energy relaxation from a dense electron-hole plasma to the lattice. The dense electron-hole plasma first undergoes Auger recombination, which reduces the carrier concentration while maintaining energy content. Longitudinal-optic (LO) phonon emission then couples energy to the lattice. LO phonon decay into acoustic phonons, and acoustic phonon propagation then causes the growth of a thermally expanded layer. Source characterization is instrumental in utilizing ultrashort x-ray pulses in time-resolved x-ray spectroscopies. By measurement of the electron beam diameter at the generation point, the pulse duration of the Thomson scattered x-rays is determined. Analysis of the Thomson scattered x-ray beam properties also provides a novel means of electron bunch characterization. Although the pulse duration is inferred for the Thomson scattering x-ray source, direct measurement is required for other x-ray pulse sources. A method based on the laser-assisted photoelectric effect (LAPE) has been demonstrated as a

  11. Ultrashort X-ray pulse science

    International Nuclear Information System (INIS)

    Chin, A.H.; Lawrence Berkeley National Lab., CA

    1998-01-01

    A variety of phenomena involves atomic motion on the femtosecond time-scale. These phenomena have been studied using ultrashort optical pulses, which indirectly probe atomic positions through changes in optical properties. Because x-rays can more directly probe atomic positions, ultrashort x-ray pulses are better suited for the study of ultrafast structural dynamics. One approach towards generating ultrashort x-ray pulses is by 90 o Thomson scattering between terawatt laser pulses and relativistic electrons. Using this technique, the author generated ∼ 300 fs, 30 keV (0.4 (angstrom)) x-ray pulses. These x-ray pulses are absolutely synchronized with ultrashort laser pulses, allowing femtosecond optical pump/x-ray probe experiments to be performed. Using the right-angle Thomson scattering x-ray source, the author performed time-resolved x-ray diffraction studies of laser-perturbated InSb. These experiments revealed a delayed onset of lattice expansion. This delay is due to the energy relaxation from a dense electron-hole plasma to the lattice. The dense electron-hole plasma first undergoes Auger recombination, which reduces the carrier concentration while maintaining energy content. Longitudinal-optic (LO) phonon emission then couples energy to the lattice. LO phonon decay into acoustic phonons, and acoustic phonon propagation then causes the growth of a thermally expanded layer. Source characterization is instrumental in utilizing ultrashort x-ray pulses in time-resolved x-ray spectroscopies. By measurement of the electron beam diameter at the generation point, the pulse duration of the Thomson scattered x-rays is determined. Analysis of the Thomson scattered x-ray beam properties also provides a novel means of electron bunch characterization. Although the pulse duration is inferred for the Thomson scattering x-ray source, direct measurement is required for other x-ray pulse sources. A method based on the laser-assisted photoelectric effect (LAPE) has been

  12. X pinch a point x-ray source

    International Nuclear Information System (INIS)

    Garg, A.B.; Rout, R.K.; Shyam, A.; Srinivasan, M.

    1993-01-01

    X ray emission from an X pinch, a point x-ray source has been studied using a pin-hole camera by a 30 kV, 7.2 μ F capacitor bank. The wires of different material like W, Mo, Cu, S.S.(stainless steel) and Ti were used. Molybdenum pinch gives the most intense x-rays and stainless steel gives the minimum intensity x-rays for same bank energy (∼ 3.2 kJ). Point x-ray source of size (≤ 0.5 mm) was observed using pin hole camera. The size of the source is limited by the size of the pin hole camera. The peak current in the load is approximately 150 kA. The point x-ray source could be useful in many fields like micro lithography, medicine and to study the basic physics of high Z plasmas. (author). 4 refs., 3 figs

  13. Study of X-ray spectrum of laser-produced gold plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Busquet, M. (CEA Centre d' Etudes de Limeil, 94 - Villeneuve-Saint-Georges (France)); Pain, D.; Bauche, J.; Luc-Koenig, E. (Centre National de la Recherche Scientifique, 91 - Orsay (France). Lab. Aime Cotton)

    1985-02-01

    Aiming at the spectroscopic diagnostic of gold plasmas, we have studied the wavelengths and intensities of X-ray spectral lines emitted in the range 4.4 to 6.2 angstroms by a target made of gold alloyed to a few percent of aluminium irradiated by a laser pulse. Aluminium yields the wavelength calibration and a monitoring of the temperature and the density of the plasma. The main features of the gold spectrum in this spectral range are due to the 3d-4f, 3p-4s and 3d-4p transitions of gold in the Co I through Cu I isoelectronic sequences.

  14. Study of X-ray spectrum of laser-produced gold plasmas

    International Nuclear Information System (INIS)

    Busquet, M.; Pain, D.; Bauche, J.; Luc-Koenig, E.

    1985-01-01

    Aiming at the spectroscopic diagnostic of gold plasmas, we have studied the wavelengths and intensities of X-ray spectral lines emitted in the range 4.4 to 6.2 angstroms by a target made of gold alloyed to a few percent of aluminium irradiated by a laser pulse. Aluminium yields the wavelength calibration and a monitoring of the temperature and the density of the plasma. The main features of the gold spectrum in this spectral range are due to the 3d-4f, 3p-4s and 3d-4p transitions of gold in the Co I through Cu I isoelectronic sequences. (orig.)

  15. X-ray imaging studies of electron cyclotron microwave-heated plasmas in the Tandem Mirror Experiment-Upgrade

    International Nuclear Information System (INIS)

    Failor, B.H.

    1986-02-01

    An x-ray pinhole camera designed to efficiently detect photons with energies between 5 and 250 keV was built to image bremsstrahlung emission from a microwave-heated hot electron plasma. This plasma is formed at one of the thermal barrier locations in the Tandem Experiment-Upgrade at Lawrence Livermore National Laboratory. The instrument consists of a lead aperture, an x-ray converter in the form of a sodium-activated cesium iodide scintillator, light intensifier electronics, and a recording medium that may either be high speed film or a CCD array. The nominal spatial and temporal resolutions are one part in 40 and 17 msec, respectively. The component requirements for optimum performance were determined both analytically and by computer simulation, and were verified experimentally. The details of these results are presented. The instrument has been used to measure x-ray emission from the TMX-U west end cell. Data acquired with the x-ray camera has allowed us to infer the temporal evolution of the mirror-trapped electron radial profile

  16. Charge exchange laboratory studies relevant to solar-wind-induced cometary and planetary X-ray emission

    Science.gov (United States)

    Eissa, Farhat

    The discovery of cometary X-ray emission for the first time in 1996, from comet Hyukatake using the Röntgen satellite (ROSAT) [Lisse, C. M. et al., 1996] was a highly surprising event. Since then, X-ray and extreme ultra violet (X-EUV) emission has been observed from a number of comets [Lisse, C. M. et al., 2001]. The production of such radiation is strongly believed to be the result of the charge exchange collisions of the minor heavy highly charged solar wind (SW) ions with cometary neutrals. This study reports the first state-selective He- like X-ray spectra resulting from single-electron capture (SEC) in charge exchange collisions of O 7+ and Ne 9+ with He and CO targets at a collision velocity of 800 km/s. The ions and velocity are typical of solar wind ions while the molecular and atomic targets are typical of cometary (CO) and interstellar (He) neutrals. The spectra have been obtained by means of simultaneous cold-target recoil ion momentum spectroscopic (COLTRIMS) and X-ray spectroscopic measurements that involved the triple-coincident detection of X- rays, scattered projectile, and target recoil ions. The spectra test the ability of theories to account for the relative population of triplet and singlet states in He-like product ions following SEC. The O 7+ +He spectra are compared with theoretical spectra based on quantal molecular-orbital close- coupling (QMOCC) and multi-channel Landau-Zener (MCLZ) calculations. In addition, all spectra have been used to extract angular momentum distributions based on the traditional 3:1 triplet-to-singlet ratio assumption for the populated states. The QMOCC and MCLZ calculations and the experimental results, however, suggest significant departures from this assumption. The extracted l - distributions are state-of-the-art at this time for modeling purposes due to the high differentiation power of the experimental procedure.

  17. Soft X-ray spectrographs for solar observations

    Science.gov (United States)

    Bruner, M. E.

    1988-01-01

    Recent advances in soft X-ray spectrometery are reviewed, with emphasis on techniques for studying the windowless region from roughly 1-100 A. Recent technological developments considered include multilayer mirrors, large-format CCD detectors which are sensitive to X-rays, position-sensitive photon counting detectors, new kinds of X-ray films, and optical systems based on gratings with nonuniform ruling spacings. Improvements in the extent and accuracy of the atomic physics data sets on which the analysis of spectroscopic observatons depend are also discussed.

  18. Dosimetry of x-rays from high-temperature plasmas

    International Nuclear Information System (INIS)

    Yamamoto, Takayoshi; Abe, Nobuyuki; Kawanishi, Masaharu

    1980-01-01

    Study on the dosimetry of ionizing radiations, especially of X-rays, emitted from high-temperature plasms has been made. As to the unpolarized Bremsstrahlung, a brief method to estimate electron temperatures with TLD is described and evaluation of average energy and current of the run-away electrons in the turbulent heating Tokamak is made by observing the half-value layer of the emitted X-rays and the total exposure per one shot of the Tokamak discharge. As to the polarized one, it is shown that the anisotropic electron temperature is related to the degree of polarization of the X-rays. Furthermore, reference is made to the possibility of developing such X-ray generators as can emit nearly monochromatic X-rays (characteristic X-rays) or polarized ones arbitrarily. (author)

  19. Plasma Emission Profile Recreation using Soft X-Ray Tomography

    Science.gov (United States)

    Page, J. W.; Mauel, M. E.; Levesque, J. P.

    2015-11-01

    With sufficient views from multiple diode arrays, soft X-ray tomography is an invaluable plasma diagnostic because it is a non-perturbing method to reconstruct the emission within the interior of the plasma. In preparation for the installation of new SXR arrays in HBT-EP, we compute high-resolution tomographic reconstructions of discharges having kink-like structures that rotate nearly rigidly. By assuming a uniform angular mapping from the kink mode rotation, Δϕ ~ ωΔ t, a temporal sequence from a single 16-diode fan array represents as many as 16 x 100 independent views. We follow the procedure described by Wang and Granetz and use Bessel basis functions to take the inverse Radon transform. This transform is fit to our data using a least-squares method to estimate the internal SXR emissivity as a sum of polar functions. By varying different parameters of the transformation, we optimize the quality of our recreation of the emission profile and quantify how the reconstruction changes with the azimuthal order of the transform. Supported by U.S. DOE Grant DE-FG02-86ER53222.

  20. Soft x-ray laser gain measurements in a recombining plasma column

    International Nuclear Information System (INIS)

    Suckewer, S.; Skinner, C.H.; Milchberg, H.; Keane, C.; Voorhees, D.

    1985-03-01

    An enhancement of approx. 100 of stimulated emission over spontaneous emission of the CVI 182 A line (one-pass gain approx. = 6.5) was measured in a recombining, magnetically confined plasma column by two independent techniques using intensity calibrated XUV monochromators. Additional confirmation that the enhancement was due to stimulated emission has been obtained with a soft x-ray mirror

  1. Measurement of core plasma temperature and rotation on W7-X made available by the x-ray imaging crystal spectrometer (XICS)

    Energy Technology Data Exchange (ETDEWEB)

    Pablant, N A; Bitter, M; Burhenn, R; Delgado-Aparicio, L; Ellis, R; Gates, D; Goto, M; Hill, K W; Langenberg, A; Lazerson, S; Mardenfeld, M; Morita, S; Neilson, G H; Oishi, T; Pedersen, T S

    2014-07-01

    A new x-ray imaging crystal spectrometer diagnostic (XICS) is currently being built for installation on W7-X. This diagnostic will contribute to the study of ion and electron thermal transport and the evolution of the radial electric field by providing high resolution temperature and rotation measurements under many plasma conditions, including ECH heated plasmas. Installation is expected before the first experimental campaign (OP1.1), making an important set of measurements available for the first W7-X plasmas. This diagnostic will also work in concert with the HR-XCS diagnostic to provide an excellent diagnostic set for core impurity transport on W7-X.

  2. Young Stellar Objects from Soft to Hard X-rays

    Science.gov (United States)

    Güdel, Manuel

    2009-05-01

    Magnetically active stars are the sites of efficient particle acceleration and plasma heating, processes that have been studied in detail in the solar corona. Investigation of such processes in young stellar objects is much more challenging due to various absorption processes. There is, however, evidence for violent magnetic energy release in very young stellar objects. The impact on young stellar environments (e.g., circumstellar disk heating and ionization, operation of chemical networks, photoevaporation) may be substantial. Hard X-ray devices like those carried on Simbol-X will establish a basis for detailed studies of these processes.

  3. Using X-ray spectroheliograph technique for investigations of laser-produced plasma under interaction with strong magnetic field

    International Nuclear Information System (INIS)

    Faenov, A.; Dyakin, V.; Magunov, A.; Pikuz, T.; Skobelev, I.; Pikuz, S.; Pisarczyk, T.; Wolowski, J.; Zielinska, E.

    1996-01-01

    A dense jet of a plasma consisting of multiply charged ions was generated in the interaction of a laser plasma with a strong external axial magnetic field. It is shown that using the high-luminosity X-ray spectroheliograph technique allows to measure plasma emission spectra with 2-dimensional spatial resolution even in the cases when these spectra have small intensities. The X-ray spectroscopy and interferometry methods are used to measure plasma parameter distributions. The dependencies of N e (z) and T e (z) measured in this paper can be used to calculate the evolution of plasma ionization state during plasma expansion. The quasihomogeneous laser jet, which appears when a laser plasma interacts with an external magnetic field can be used not only to form an active medium of a short wavelength laser, but probably also to tackle the urgent problem of transport in a laser ion injector. (orig.)

  4. Using X-ray spectroheliograph technique for investigations of laser-produced plasma under interaction with strong magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Faenov, A. [MISDC of VNIIFTRI, Mendeleevo (Russian Federation); Dyakin, V. [MISDC of VNIIFTRI, Mendeleevo (Russian Federation); Magunov, A. [MISDC of VNIIFTRI, Mendeleevo (Russian Federation); Pikuz, T. [MISDC of VNIIFTRI, Mendeleevo (Russian Federation); Skobelev, I. [MISDC of VNIIFTRI, Mendeleevo (Russian Federation); Pikuz, S. [Rossijskaya Akademiya Nauk, Moscow (Russian Federation). Fizicheskij Inst.; Kasperczyk, A. [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); Pisarczyk, T. [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); Wolowski, J. [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); Zielinska, E. [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland)

    1996-08-01

    A dense jet of a plasma consisting of multiply charged ions was generated in the interaction of a laser plasma with a strong external axial magnetic field. It is shown that using the high-luminosity X-ray spectroheliograph technique allows to measure plasma emission spectra with 2-dimensional spatial resolution even in the cases when these spectra have small intensities. The X-ray spectroscopy and interferometry methods are used to measure plasma parameter distributions. The dependencies of N{sub e}(z) and T{sub e}(z) measured in this paper can be used to calculate the evolution of plasma ionization state during plasma expansion. The quasihomogeneous laser jet, which appears when a laser plasma interacts with an external magnetic field can be used not only to form an active medium of a short wavelength laser, but probably also to tackle the urgent problem of transport in a laser ion injector. (orig.).

  5. X-ray spectrometer spectrograph telescope system. [for solar corona study

    Science.gov (United States)

    Bruner, E. C., Jr.; Acton, L. W.; Brown, W. A.; Salat, S. W.; Franks, A.; Schmidtke, G.; Schweizer, W.; Speer, R. J.

    1979-01-01

    A new sounding rocket payload that has been developed for X-ray spectroscopic studies of the solar corona is described. The instrument incorporates a grazing incidence Rowland mounted grating spectrograph and an extreme off-axis paraboloic sector feed system to isolate regions of the sun of order 1 x 10 arc seconds in size. The focal surface of the spectrograph is shared by photographic and photoelectric detection systems, with the latter serving as a part of the rocket pointing system control loop. Fabrication and alignment of the optical system is based on high precision machining and mechanical metrology techniques. The spectrograph has a resolution of 16 milliangstroms and modifications planned for future flights will improve the resolution to 5 milliangstroms, permitting line widths to be measured.

  6. X-ray diagnostics for laser matter interaction experiments

    International Nuclear Information System (INIS)

    Troussel, Ph.

    2000-01-01

    Advances in the field of laser-driven inertially confined thermonuclear fusion research since the early 1990's are reviewed. It covers the experimental techniques used to study the interaction of laser radiation with matter and high density plasma. A high performance instrumentation (diagnostics) for observation of X radiation (from a few eV to a few keV) will be required to understand the physical processes involved in the interaction. This paper is a three-part: first part, describes diagnostics metrology realized around different X-ray sources (synchrotron, laser plasma...); a second part, synthesizes theoretical and experimental X-ray optics studies and show the interest for direct applications as X-ray spectroscopy and X-ray imaging around laser-produced plasma; a third part, is a review of high resolution X-ray imaging, performances of these optical system were summarized. (author)

  7. Design calculations for a xenon plasma x-ray shield to protect the NIF optical Thomson scattering diagnostic

    Energy Technology Data Exchange (ETDEWEB)

    Swadling, G. F.; Ross, J. S.; Datte, P.; Moody, J.; Divol, L.; Jones, O.; Landen, O. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2016-11-15

    An Optical Thomson Scattering (OTS) diagnostic is currently being developed for the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory. This diagnostic is designed to make measurements of the hohlraum plasma parameters, such as the electron temperature and the density, during inertial confinement fusion (ICF) experiments. NIF ICF experiments present a very challenging environment for optical measurements; by their very nature, hohlraums produce intense soft x-ray emission, which can cause “blanking” (radiation induced opacity) of the radiation facing optical components. The soft x-ray fluence at the surface of the OTS blast shield, 60 cm from the hohlraum, is estimated to be ∼8 J cm{sup −2}. This is significantly above the expected threshold for the onset of “blanking” effects. A novel xenon plasma x-ray shield is proposed to protect the blast shield from x-rays and mitigate “blanking.” Estimates suggest that an areal density of 10{sup 19} cm{sup −2} Xe atoms will be sufficient to absorb 99.5% of the soft x-ray flux. Two potential designs for this shield are presented.

  8. Detection of x-rays emitted from a plasma focus device with energy of 2.8 KJ, and its applications in plasma diagnostic and radiography

    International Nuclear Information System (INIS)

    AL-Hawat, Sh.; Akel, M.

    2011-06-01

    The local plasma focus device was modified by replacing the old capacitors (25μF,20 kV ,1.43μH ) and the open spark gap by new capacitors with (25μF,20 kV ,200 nH ) and a new closed spark gap, so instead of a current of 50 kA as a maximum value we obtained a maximum current about 120 kA. The modified device is capable now to generate x-rays, which was confirmed by taking some radiographies for metallic pieces, electronic elements and others . In addition to that some diagnostics were carried out on the device using Ohm voltage divider to record voltage curves, Rogovskii coil for measuring the current, and five channel diodes to evaluate the temporal evolution of x-rays generated in the device working on argon vs. pressure and voltage. The generation of the soft x-ray emission in a low energy 2.8 kJ plasma focus device operated with argon using a detector of five PIN-Si BPX-65 diodes filtered with different foils of Mylar, Al and Cu. Spectral analysis using the recorded x-ray signals ratio method shows that there are two components in the x-ray emissions: one arising from the focused argon plasma with temperature of 2.5 keV and the other arising from the electron beam activity on copper anode, where the second component is predominant in most of investigated experiments due to the used of solid anode. Numerical experiments were carried out using five phases radiative Lee model RADPF5.15d-dd with N 2 , O 2 , Ar, Ne gases on plasma focus device AECS PF1-2 (or PF SY1-2) for its characterization and soft x-ray optimization. (author)

  9. High-throughput roll-to-roll X-ray characterization of polymer solar cell active layers

    DEFF Research Database (Denmark)

    Böttiger, Arvid P.L.; Jørgensen, Mikkel; Menzel, Andreas

    2012-01-01

    Synchrotron-based X-rays were used to probe active materials for polymer solar cells on flexible polyester foil. The active material was coated onto a flexible 130 micron thick polyester foil using roll-to-roll differentially pumped slot-die coating and presented variation in composition, thickness...

  10. Observations of EUV and X-ray Emission from Comets

    Science.gov (United States)

    Lisse, C.

    The unexpected discovery of x-ray emission from Comet Hyakutake in March 1996 (Lisse et al. 1996) produced a number of questions about the physical mechanism producing the radiation. The original detection and subsequent observations have shown that the very soft (best fit thermal bremsstrahlung model kT0.2 keV) emission is due to an interaction between the solar wind and the comet's atmosphere. Using the results from the more than 15 comets detected to date in x-rays, I report here on the latest results on cometary x-ray emission, including new results from Chandra, and show that charge exchange between highly ionized minor ions in the solar wind and neutral gases in the cometary coma is the most likely operative mechanism. I then use this result to study a number of problems of astrophysical interest: the nature of the cometary coma, other possible sources of x-ray emission in the solar system, the structure of the solar wind in the heliosphere, and the source of the local x-ray background.

  11. Spatial coherence properties of a compact and ultrafast laser-produced plasma keV x-ray source

    International Nuclear Information System (INIS)

    Boschetto, D.; Mourou, G.; Rousse, A.; Mordovanakis, A.; Hou, Bixue; Nees, J.; Kumah, D.; Clarke, R.

    2007-01-01

    The authors use Fresnel diffraction from knife-edges to demonstrate the spatial coherence of a tabletop ultrafast x-ray source produced by laser-plasma interaction. Spatial coherence is achieved in the far field by producing micrometer-scale x-ray spot dimensions. The results show an x-ray source size of 6 μm that leads to a transversal coherence length of 20 μm at a distance of 60 cm from the source. Moreover, they show that the source size is limited by the spatial spread of the absorbed laser energy

  12. X-ray absorption spectroscopy of aluminum z-pinch plasma with tungsten backlighter planar wire array source

    Energy Technology Data Exchange (ETDEWEB)

    Osborne, G. C.; Kantsyrev, V. L.; Safronova, A. S.; Esaulov, A. A.; Weller, M. E.; Shrestha, I.; Shlyaptseva, V. V. [Physics Department, University of Nevada, Reno, Reno, Nevada 89557 (United States); Ouart, N. D. [Naval Research Laboratory, Washington, D.C. 20375 (United States)

    2012-10-15

    Absorption features from K-shell aluminum z-pinch plasmas have recently been studied on Zebra, the 1.7 MA pulse power generator at the Nevada Terawatt Facility. In particular, tungsten plasma has been used as a semi-backlighter source in the generation of aluminum K-shell absorption spectra by placing a single Al wire at or near the end of a single planar W array. All spectroscopic experimental results were recorded using a time-integrated, spatially resolved convex potassium hydrogen phthalate (KAP) crystal spectrometer. Other diagnostics used to study these plasmas included x-ray detectors, optical imaging, laser shadowgraphy, and time-gated and time-integrated x-ray pinhole imagers. Through comparisons with previous publications, Al K-shell absorption lines are shown to be from much lower electron temperature ({approx}10-40 eV) plasmas than emission spectra ({approx}350-500 eV).

  13. Characteristics of soft X-ray lens

    International Nuclear Information System (INIS)

    Qin Yi

    2007-12-01

    A soft X-lens was devised with waveguide X-ray optics of total external reflection (TER). The lens consists of a stack of 1 387 TER waveguides with inner diameter of 0.45 mm and outer diameter of 0.60 mm. With the help of plasma sources of soft X-ray radiation, high density of pure soft X-ray radiation (without plasma expansion fragments) with broad-band spectral range can be obtained at the focus of the lens. As laser-plasma is considered, the radiation density of 1.3 x 10 5 W/cm 2 is obtained, the transmission coefficient is 18.6%, the ratio of the density at the focus with and without the lens is 1000 and the radiation capture is 28.9 degree. The density of 0.5 TW/cm 2 can be obtained as far as Qiang-Guang I facility is considered. (authors)

  14. Spectral tomographic analysis of Bremsstrahlung X-rays generated in a laser-produced plasma

    Czech Academy of Sciences Publication Activity Database

    Rhee, Y.-J.; Nam, S. M.; Peebles, W.; Sawada, H.; Wei, M.; Vaisseau, X.; Sasaki, T.; Giuffrida, Lorenzo; Hulin, S.; Vauzour, B.; Santos, J.J.; Batani, D.; McLean, H. S.; Patel, P. K.; Li, Y.; Yuan, D. W.; Zhang, K.; Zhong, J. Y.; Fu, C. B.; Hua, N.; Li, K.; Zhang, Y.; Zhu, J. Q.; Kim, I. J.; Jeon, J. H.; Jeong, T.M.; Choi, I.W.; Lee, H. W.; Sung, J.H.; Lee, S.K.; Nam, C.H.

    2016-01-01

    Roč. 34, č. 4 (2016), s. 645-654 ISSN 0263-0346 R&D Projects: GA MŠk LQ1606; GA MŠk EF15_008/0000162 Grant - others:ELI Beamlines(XE) CZ.02.1.01/0.0/0.0/15_008/0000162 Institutional support: RVO:68378271 Keywords : Bremsstrahlung X-ray * filter stack spectrometer * laser-produced plasma Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.420, year: 2016

  15. 13th International Conference on X-Ray Lasers

    CERN Document Server

    Gautier, Julien; Ros, David; Zeitoun, Philippe

    2014-01-01

    These proceedings comprise of invited and contributed papers presented at the 13th International Conference on X-Ray Lasers (ICXRL 2012) which was held 11–15 June 2012 in Paris, in the famous Quartier Latin, inside the historical Center of Cordeliers. This conference is part of a continuing series dedicated to recent developments and applications of x-ray lasers and other coherent x-ray sources with attention to supporting technologies and instrumentation. New results in the generation of intense, coherent x-rays and progress towards practical devices and their applications are reported in these proceedings, including areas of research in plasma-based x-ray lasers, 4th generation accelerator-based sources and higher harmonic generation. Recent achievements related to the increase of the repetition rate up to 100 Hz and shorter wavelength collisional plasma-based soft x-ray lasers down to about 7 nm are presented. Seeding the amplifying plasma with a femtosecond high-order harmonic of infrared laser was fore...

  16. Laser-Hole Boring into Overdense Plasmas Measured with Soft X-Ray Laser Probing

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, K [Institute of Laser Engineering, Osaka University, Yamada Oka 2-6, Suita, Osaka 565-0871, (Japan); Kodama, R [Institute of Laser Engineering, Osaka University, Yamada Oka 2-6, Suita, Osaka 565-0871, (Japan); Tanaka, K A [Institute of Laser Engineering, Osaka University, Yamada Oka 2-6, Suita, Osaka 565-0871, (Japan); Hashimoto, H [Institute of Laser Engineering, Osaka University, Yamada Oka 2-6, Suita, Osaka 565-0871, (Japan); Kato, Y [Institute of Laser Engineering, Osaka University, Yamada Oka 2-6, Suita, Osaka 565-0871, (Japan); Mima, K [Institute of Laser Engineering, Osaka University, Yamada Oka 2-6, Suita, Osaka 565-0871, (Japan); Weber, F A [University of California, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States); Barbee, Jr, T W [University of California, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States); Da Silva, L B [University of California, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States)

    2000-03-13

    A laser self-focused channel formation into overdense plasmas was observed using a soft x-ray laser probe system with a grid image refractometry (GIR) technique. 1.053 {mu}m laser light with a 100 ps pulse duration was focused onto a preformed plasma at an intensity of 2x10{sup 17} W /cm{sup 2} . Cross sections of the channel were obtained which show a 30 {mu}m diameter in overdense plasmas. The channel width in the overdense region was kept narrow as a result of self-focusing. Conically diverging density ridges were also observed along the channel, indicating a Mach cone created by a shock wave due to the supersonic propagation of the channel front. (c) 2000 The American Physical Society.

  17. Laser-Hole Boring into Overdense Plasmas Measured with Soft X-Ray Laser Probing

    International Nuclear Information System (INIS)

    Takahashi, K.; Kodama, R.; Tanaka, K. A.; Hashimoto, H.; Kato, Y.; Mima, K.; Weber, F. A.; Barbee, T. W. Jr.; Da Silva, L. B.

    2000-01-01

    A laser self-focused channel formation into overdense plasmas was observed using a soft x-ray laser probe system with a grid image refractometry (GIR) technique. 1.053 μm laser light with a 100 ps pulse duration was focused onto a preformed plasma at an intensity of 2x10 17 W /cm 2 . Cross sections of the channel were obtained which show a 30 μm diameter in overdense plasmas. The channel width in the overdense region was kept narrow as a result of self-focusing. Conically diverging density ridges were also observed along the channel, indicating a Mach cone created by a shock wave due to the supersonic propagation of the channel front. (c) 2000 The American Physical Society

  18. MIT modular x-ray source systems for the study of plasma diagnostics

    Science.gov (United States)

    Coleman, J. W.; Wenzel, K. W.; Petrasso, R. D.; Lo, D. H.; Li, C. K.; Lierzer, J. R.; Wei, T.

    1992-10-01

    Two new x-ray source systems are now on line at our facility. Each provides an e-beam to 25 kV. Targets are interchangeable between machines, and four x-ray detectors may be used simultaneously with a target. The gridded e-gun of the RACEHORSE system gives a 0.5-1.0-cm pulsable spot on target. The nongridded e-gun of the SCORPION system provides a 0.3-mm or smaller dc microspot on target. RACEHORSE is being used to study and characterize type-II diamond photoconductors for use in diagnosing plasmas, while SCORPION is being used to develop a slitless spectrograph using photographic film. Source design details and some RACEHORSE results are presented.

  19. Quiet Sun X-rays as Signature for New Particles

    CERN Document Server

    Zioutas, Konstantin; Di Lella, L; Hoffmann, Dieter H H; Jacoby, J; Papaevangelou, T

    2004-01-01

    We have studied published data from the Yohkoh solar X-ray mission, with the purpose of searching for signals from radiative decays of new, as yet undiscovered massive neutral particles. This search is based on the prediction that solar axions of the Kaluza-Klein type should result in the emission of X-rays from the Sun direction beyond the limb with a characteristic radial distribution. These X-rays should be observed more easily during periods of quiet Sun. An additional signature is the observed emission of hard X-rays by SMM, NEAR and RHESSI. The recent observation made by RHESSI of a continuous emission from the non-flaring Sun of X-rays in the 3 to ~15 keV range fits the generic axion scenario. This work also suggests new analyses of existing data, in order to exclude instrumental effects; it provides the rationale for targeted observations with present and upcoming (solar) X-ray telescopes, which can provide the final answer on the nature of the signals considered here. Such measurements become more pr...

  20. Development of a plasma system as a source of radiation for X-ray microscopy

    International Nuclear Information System (INIS)

    Neff, W.; Lebert, R.; Holz, R.

    1992-01-01

    During the period of the report, an X-ray source was developed for a laboratory X-ray microscope based on a plasma focus. Nitrogen is used as the discharge gas. The Lyman α line (λ = 2.48 nm) of nitrogen ions N VII similar to hydrogen is used for the image in the microscope. This line is favourably situated at the start of the water window (2.33 - 4.37 nm), so that the microscope is particularly suitable for the examination of biological objects. (orig.) [de

  1. X-Ray Source Heights in a Solar Flare: Thick-Target Versus Thermal Conduction Front Heating

    Science.gov (United States)

    Reep, J. W.; Bradshaw, S. J.; Holman, G. D.

    2016-01-01

    Observations of solar flares with RHESSI have shown X-ray sources traveling along flaring loops, from the corona down to the chromosphere and back up. The 2002 November 28 C1.1 flare, first observed with RHESSI by Sui et al. and quantitatively analyzed by O'Flannagain et al., very clearly shows this behavior. By employing numerical experiments, we use these observations of X-ray source height motions as a constraint to distinguish between heating due to a non-thermal electron beam and in situ energy deposition in the corona. We find that both heating scenarios can reproduce the observed light curves, but our results favor non-thermal heating. In situ heating is inconsistent with the observed X-ray source morphology and always gives a height dispersion with photon energy opposite to what is observed.

  2. X-ray spectroscopy for high energy-density X pinch density and temperature measurements (invited)

    International Nuclear Information System (INIS)

    Pikuz, S.A.; Shelkovenko, T.A.; Chandler, K.M.; Mitchell, M.D.; Hammer, D.A.; Skobelev, I.Y.; Shlyaptseva, A.S.; Hansen, S.B.

    2004-01-01

    X pinch plasmas produced from fine metal wires can reach near solid densities and temperatures of 1 keV or even more. Plasma conditions change on time scales as short as 5-10 ps as determined using an x-ray streak camera viewing a focusing crystal spectrograph or directly viewing the plasma through multiple filters on a single test. As a result, it is possible to determine plasma conditions from spectra with ∼10 ps time resolution. Experiments and theory are now coming together to give a consistent picture of the dynamics and kinetics of these high energy density plasmas with very high temporal and spatial precision. A set of diagnostic techniques used in experiments for spectrally, temporally, and spatially resolved measurements of X pinch plasmas is described. Results of plasma parameter determination from these measurements are presented. X ray backlighting of one x-pinch by another with ∼30 ps x-ray pulses enables the dynamics and kinetics to be correlated in time

  3. Hard X-ray bremsstrahlung production in solar flares by high-energy proton beams

    Science.gov (United States)

    Emslie, A. G.; Brown, J. C.

    1985-01-01

    The possibility that solar hard X-ray bremsstrahlung is produced by acceleration of stationary electrons by fast-moving protons, rather than vice versa, as commonly assumed, was investigated. It was found that a beam of protons which involves 1836 times fewer particles, each having an energy 1836 times greater than that of the electrons in the equivalent electron beam model, has exactly the same bremsstrahlung yield for a given target, i.e., the mechanism has an energetic efficiency equal to that of conventional bremsstrahlung models. Allowance for the different degrees of target ionization appropriate to the two models (for conventional flare geometries) makes the proton beam model more efficient than the electron beam model, by a factor of order three. The model places less stringent constraints than a conventional electron beam model on the flare energy release mechanism. It is also consistent with observed X-ray burst spectra, intensities, and directivities. The altitude distribution of hard X-rays predicted by the model agrees with observations only if nonvertical injection of the protons is assumed. The model is inconsistent with gamma-ray data in terms of conventional modeling.

  4. Solar flares observed simultaneously with SphinX, GOES and RHESSI

    Science.gov (United States)

    Mrozek, Tomasz; Gburek, Szymon; Siarkowski, Marek; Sylwester, Barbara; Sylwester, Janusz; Kępa, Anna; Gryciuk, Magdalena

    2013-07-01

    In February 2009, during recent deepest solar minimum, Polish Solar Photometer in X-rays (SphinX) begun observations of the Sun in the energy range of 1.2-15 keV. SphinX was almost 100 times more sensitive than GOES X-ray Sensors. The silicon PIN diode detectors used in the experiment were carefully calibrated on the ground using Synchrotron Radiation Source BESSY II. The SphinX energy range overlaps with the Ramaty High Energy Solar Spectroscopic Imager (RHESSI) energy range. The instrument provided us with observations of hundreds of very small flares and X-ray brightenings. We have chosen a group of solar flares observed simultaneously with GOES, SphinX and RHESSI and performed spectroscopic analysis of observations wherever possible. The analysis of thermal part of the spectra showed that SphinX is a very sensitive complementary observatory for RHESSI and GOES.

  5. Recombining Plasma and Gamma-Ray Emission in the Mixed-morphology Supernova Remnant 3C 400.2

    Energy Technology Data Exchange (ETDEWEB)

    Ergin, T. [TUBITAK Space Technologies Research Institute, ODTU Campus, 06800, Ankara (Turkey); Sezer, A. [Department of Electrical-Electronics Engineering, Avrasya University, 61250 Trabzon (Turkey); Sano, H.; Fukui, Y. [Department of Physics, Nagoya University, Chikusa-ku, Nagoya, Aichi 464–8601 (Japan); Yamazaki, R., E-mail: ergin.tulun@gmail.com, E-mail: aytap.sezer@avrasya.edu.tr, E-mail: sano@a.phys.nagoya-u.ac.jp [Department of Physics and Mathematics, Aoyama Gakuin University, 5-10-1 Fuchinobe, Sagamihara 252–5258 (Japan)

    2017-06-10

    3C 400.2 belongs to the mixed-morphology supernova remnant class, showing center-filled X-ray and shell-like radio morphology. We present a study of 3C 400.2 with archival Suzaku and Fermi -LAT observations. We find recombining plasma (RP) in the Suzaku spectra of north–east and south–east regions. The spectra of these regions are well described by two-component thermal plasma models: the hard component is in RP, while the soft component is in collisional ionization equilibrium (CIE) conditions. The RP has enhanced abundances, indicating that the X-ray emission has an ejecta origin, while the CIE has solar abundances associated with the interstellar material. The X-ray spectra of north–west and south–west regions are best fitted by a two-component thermal plasma model: an ionizing and a CIE plasma. We have detected GeV gamma-ray emission from 3C 400.2 at the level of ∼5 σ , assuming a point-like source model with a power-law (PL) type spectrum. We have also detected a new GeV source at the level of ∼13 σ, assuming a Gaussian extension model with a PL-type spectrum in the neighborhood of the supernova remnant. We report the analysis results of 3C 400.2 and the new extended gamma-ray source, and discuss the nature of gamma-ray emission of 3C 400.2 in the context of existing NANTEN CO data, Dominion Radio Astrophysical Observatory H i data, and the Suzaku X-ray analysis results.

  6. Study of emission process in hot, optically thin plasma: application to solar active regions

    International Nuclear Information System (INIS)

    Steenman-Clark, Lois.

    1983-06-01

    Analysis of soft X-ray got in hot and weak density plasmas, such as those in TOKAMAKS and in solar flares, needs a detailed knowledge of emission processes. In this work are presented spectroscopic diagnostics which can be deduced from such spectra analysis and results are applied to magnesium solar spectrum analysis. An important improvement is brought to collisional calculation corresponding to forbidden line populating. For this line, The relative importance of autoionizing states effect, called also resonance effect is studied [fr

  7. Fast plasma discharge capillary design as a high power throughput soft x-ray emission source.

    Science.gov (United States)

    Wyndham, E S; Favre, M; Valdivia, M P; Valenzuela, J C; Chuaqui, H; Bhuyan, H

    2010-09-01

    We present the experimental details and results from a low energy but high repetition rate compact plasma capillary source for extreme ultraviolet and soft x-ray research and applications. Two lengths of capillary are mounted in two versions of a closely related design. The discharge operates in 1.6 and 3.2 mm inner diameter alumina capillaries of lengths 21 and 36 mm. The use of water both as dielectric and as coolant simplifies the compact low inductance design with nanosecond discharge periods. The stored electrical energy of the discharge is approximately 0.5 J and is provided by directly charging the capacitor plates from an inexpensive insulated-gate bipolar transistor in 1 μs or less. We present characteristic argon spectra from plasma between 30 and 300 Å as well as temporally resolved x-ray energy fluence in discrete bands on axis. The spectra also allow the level of ablated wall material to be gauged and associated with useful capillary lifetime according to the chosen configuration and energy storage. The connection between the electron beams associated with the transient hollow cathode mechanism, soft x-ray output, capillary geometry, and capillary lifetime is reported. The role of these e-beams and the plasma as measured on-axis is discussed. The relation of the electron temperature and the ionization stages observed is discussed in the context of some model results of ionization in a non-Maxwellian plasma.

  8. Conditions for soft x-ray lasing action in a confined plasma column

    International Nuclear Information System (INIS)

    Suckewer, S.; Fishman, H.

    1979-09-01

    The idea of using a multi-Z (e.g., carbon, oxygen) thin plasma column as a medium for soft x-ray lasing action is presented. A plasma confined by a strong magnetic field is first heated by a CO 2 -laser, and then cools rapidly by radiation losses. This leads to a level population inversion of hydrogen-like carbon or oxygen ions. Two computational models are presented. One uses given electron temperature, T/sub e/(t), evolutions. The other uses T/sub e/(t) calculated from an energy balance equation ith CO 2 -laser beam power as a parameter. According to calculations, a total gain of G > 100 is expected for 3 → 2 and G > 10 for 4 → 2 transitions (lambda = 182 A and lambda = 135 A, respectively) for CVI ions using a CO 2 -laser beam with power approx. 5 x 10 10 W for plasma column heating

  9. X-ray emission from comets

    International Nuclear Information System (INIS)

    Dennerl, Konrad

    1999-01-01

    When comet Hyakutake (C/1996 B2) encountered Earth in March 1996 at a minimum distance of only 15 million kilometers (40 times the distance of the moon), x-ray and extreme ultraviolet emission was discovered for the first time from a comet. The observations were performed with the astronomy satellites ROSAT and EUVE. A systematic search for x-rays from comets in archival data, obtained during the ROSAT all-sky survey in 1990/91, resulted in the discovery of x-ray emission from four additional comets. They were detected at seven occasions in total, when they were optically 300 to 30 000 times fainter than Hyakutake. These findings indicated that comets represent a new class of celestial x-ray sources. Subsequent detections of x-ray emission from additional comets with the satellites ROSAT, EUVE, and BeppoSAX confirmed this conclusion. The x-ray observations have obviously revealed the presence of a process in comets which had escaped attention until recently. This process is most likely charge exchange between highly charged heavy ions in the solar wind and cometary neutrals. The solar wind, a stream of particles continuously emitted from the sun with ≅ 400 km s -1 , consists predominantly of protons, electrons, and alpha particles, but contains also a small fraction (≅0.1%) of highly charged heavier ions, such as C 6+ ,O 6+ ,Ne 8+ ,Si 9+ ,Fe 11+ . When these ions capture electrons from the cometary gas, they attain highly excited states and radiate a large fraction of their excitation energy in the extreme ultraviolet and x-ray part of the spectrum. Charge exchange reproduces the intensity, the morphology and the spectrum of the observed x-ray emission from comets very well

  10. Multi-energy soft-x-ray technique for impurity transport measurements in the fusion plasma edge

    International Nuclear Information System (INIS)

    Clayton, D J; Tritz, K; Stutman, D; Finkenthal, M; Kumar, D; Kaye, S M; LeBlanc, B P; Paul, S; Sabbagh, S A

    2012-01-01

    A new diagnostic technique was developed to produce high-resolution impurity transport measurements of the steep-gradient edge of fusion plasmas. Perturbative impurity transport measurements were performed for the first time in the NSTX plasma edge (r/a ∼ 0.6 to the SOL) with short neon gas puffs, and the resulting line and continuum emission was measured with the new edge multi-energy soft-x-ray (ME-SXR) diagnostic. Neon transport is modeled with the radial impurity transport code STRAHL and the resulting x-ray emission is computed using the ADAS atomic database. The radial transport coefficient profiles D(r) and v(r), and the particle flux from the gas puff Φ(t), are the free parameters in this model and are varied to find the best fit to experimental x-ray emissivity measurements, with bolometry used to constrain the impurity source. Initial experiments were successful and results were consistent with previous measurements of core impurity transport and neoclassical transport calculations. New diagnostic tools will be implemented on NSTX-U to further improve these transport measurements. (paper)

  11. Study of electrons distribution produced by laser-plasma interaction on x-ray generation

    International Nuclear Information System (INIS)

    Nikzad, L.; Sadighi-Bonabi, R.

    2010-01-01

    Complete text of publication follows. In the present work, X-ray beams are generated from interaction of relativistic electron beams produced by interaction of 500 mJ, 30 femtosecond Ti:sapphire laser pulses with thin solid targets such as lead, molybdenum and tungsten. After interaction of an intense pulsed laser with He gas-jet, a micron-scale laser produced plasma, creates and accelerates electron bunches, which propagate in the ion channel produced in the wake of the laser pulse. When an electron bunch is injected into the bubble in phase with its field, it will gain relativistic energies within very short distance. These accelerated electrons with Megaelectron-Volt energy and different distributions, can interact with targets to generate X-ray radiation with Kiloelectron-Volt energy, providing to be close enough to the gas-jet, where the relativistic accelerated electrons exist. Here, to determine the results, Monte Carlo simulation (MCNP-4C code) is employed to present Bremsstrahlung and characteristic X-ray production by quasi-Maxwellian and quasi-monoenergetic electron beams for three samples with different thicknesses. The outcome shows that for one specific electron spectrum and one definite target, the energy which the maximum characteristic x-ray flux takes place, varies with thickness. Also, for each material the energy which this maximum happens is constant for all thicknesses, for both produced electron spectra. For each sample, x-ray flux is calculated for different thicknesses and the thickness which the maximum characteristic x-ray flux occurs is obtained. Besides, it is concluded that by increasing the atomic number of the target, maximum X-ray flux moves towards higher energy. Also, comparison of the results for three targets and two electron distributions shows that by using quasi-monoenergetic electron spectra, more intense and narrower characteristic X-ray can be produced compared to the quasi-Maxwellian electron distribution, almost for all

  12. Self-consistent one-dimensional modelling of x-ray laser plasmas

    International Nuclear Information System (INIS)

    Wan, A.S.; Walling, R.S.; Scott, H.A.; Mayle, R.W.; Osterheld, A.L.

    1992-01-01

    This paper presents the simulation of a planar, one-dimensional expanding Ge x-ray laser plasma using a new code which combines hydrodynamics, laser absorption, and detailed level population calculations within the same simulation. Previously, these simulations were performed in separate steps. We will present the effect of line transfer on gains and excited level populations and compare the line transfer result with simulations using escape probabilities. We will also discuss the impact of different atomic models on the accuracy of our simulation

  13. Enhanced brightness x-ray lasers

    International Nuclear Information System (INIS)

    Wan, A.S.; Cauble, R.C.; Da Silva, L.B.; Moreno, J.C.; Nilsen, J.

    1994-09-01

    We are developing short-pulsed, enhanced-brightness, and coherent x-ray lasers (XRLs) for applications in areas such as plasma imaging. In a traveling wave pump setup the optical laser creating the XRL plasma sweeps along the lasant axis at the same speed as the x-rays. This technique becomes increasingly important as the target length increases and the gain duration shortens. An order of magnitude increase in output energy was measured with vs without traveling wave pump. Using multiple pulse techniques and multilayer mirrors to inject the output of one pulse back into the plasma formed by a later pulse we have begun to develop the x-ray analog of a multi-pass amplifler. The use of multiple pulses separated by as much as 1.6 ns reduces multilayer mirror damage. This injection technique is demonstrated by imaging the near-field emission profiles of the XRL. The addition of multilayer beamsplitter will allow us to effectively produce a soft XRL cavity

  14. The Multi-Instrument (EVE-RHESSI) DEM for Solar Flares, and Implications for Residual Non-Thermal Soft X-Ray Emission

    Science.gov (United States)

    McTiernan, James M.; Caspi, Amir; Warren, Harry

    2015-04-01

    In the soft X-ray energy range, solar flare spectra are typically dominated by thermal emission. The low energy extent of non-thermal emission can only be loosely quantified using currently available X-ray data. To address this issue, we combine observations from the EUV Variability Experiment (EVE) on-board the Solar Dynamics Observatory (SDO) with X-ray data from the Reuven Ramaty High Energy Spectroscopic Imager (RHESSI). The improvement over the isothermal approximation is intended to resolve the ambiguity in the range where the thermal and non-thermal components may have similar photon fluxes. This "crossover" range can extend up to 30 keV for medium to large solar flares.Previous work (Caspi et.al. 2014ApJ...788L..31C) has concentrated on obtaining DEM models that fit both instruments' observations well. Now we are interested in any breaks and cutoffs in the "residual" non-thermal spectrum; i.e., the RHESSI spectrum that is left over after the DEM has accounted for the bulk of the soft X-ray emission. Thermal emission is again modeled using a DEM that is parametrized as multiple gaussians in temperature; the non-thermal emission is modeled as a photon spectrum obtained using a thin-target emission model ('thin2' from the SolarSoft Xray IDL package). Spectra for both instruments are fit simultaneously in a self-consistent manner. The results for non-thermal parameters then are compared with those found using RHESSI data alone, with isothermal and double-thermal models.

  15. Measurements of fast electron beams and soft X-ray emission from plasma-focus experiments

    Directory of Open Access Journals (Sweden)

    Surała Władysław

    2016-06-01

    Full Text Available The paper reports results of the recent experimental studies of pulsed electron beams and soft X-rays in plasma-focus (PF experiments carried out within a modified PF-360U facility at the NCBJ, Poland. Particular attention was focused on time-resolved measurements of the fast electron beams by means of two different magnetic analyzers, which could record electrons of energy ranging from about 41 keV to about 715 keV in several (6 or 8 measuring channels. For discharges performed with the pure deuterium filling, many strong electron signals were recorded in all the measuring channels. Those signals were well correlated with the first hard X-ray pulse detected by an external scintillation neutron-counter. In some of the analyzer channels, electron spikes (lasting about dozens of nanoseconds and appearing in different instants after the current peculiarity (so-called current dip were also recorded. For several discharges, fast ion beams, which were emitted along the z-axis and recorded with nuclear track detectors, were also investigated. Those measurements confirmed a multibeam character of the ion emission. The time-integrated soft X-ray images, which were taken side-on by means of a pinhole camera and sensitive X-ray films, showed the appearance of some filamentary structures and so-called hot spots. The application of small amounts of admixtures of different heavy noble gases, i.e. of argon (4.8% volumetric, krypton (1.6% volumetric, or xenon (0.8% volumetric, decreased intensity of the recorded electron beams, but increased intensity of the soft X-ray emission and showed more distinct and numerous hot spots. The recorded electron spikes have been explained as signals produced by quasi-mono-energetic microbeams emitted from tiny sources (probably plasma diodes, which can be formed near the observed hot spots.

  16. Planetary Protection: X-ray Super-Flares Aid Formation of "Solar Systems"

    Science.gov (United States)

    2005-05-01

    New results from NASA's Chandra X-ray Observatory imply that X-ray super-flares torched the young Solar System. Such flares likely affected the planet-forming disk around the early Sun, and may have enhanced the survival chances of Earth. By focusing on the Orion Nebula almost continuously for 13 days, a team of scientists used Chandra to obtain the deepest X-ray observation ever taken of this or any star cluster. The Orion Nebula is the nearest rich stellar nursery, located just 1,500 light years away. These data provide an unparalleled view of 1400 young stars, 30 of which are prototypes of the early Sun. The scientists discovered that these young suns erupt in enormous flares that dwarf - in energy, size, and frequency -- anything seen from the Sun today. Illustration of Large Flares Illustration of Large Flares "We don't have a time machine to see how the young Sun behaved, but the next best thing is to observe Sun-like stars in Orion," said Scott Wolk of Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. "We are getting a unique look at stars between one and 10 million years old - a time when planets form." A key result is that the more violent stars produce flares that are a hundred times as energetic as the more docile ones. This difference may specifically affect the fate of planets that are relatively small and rocky, like the Earth. "Big X-ray flares could lead to planetary systems like ours where Earth is a safe distance from the Sun," said Eric Feigelson of Penn State University in University Park, and principal investigator for the international Chandra Orion Ultradeep Project. "Stars with smaller flares, on the other hand, might end up with Earth-like planets plummeting into the star." Animation of X-ray Flares from a Young Sun Animation of X-ray Flares from a "Young Sun" According to recent theoretical work, X-ray flares can create turbulence when they strike planet-forming disks, and this affects the position of rocky planets as they

  17. Saturable absorption of an X-ray free-electron-laser heated solid-density aluminum plasma

    Czech Academy of Sciences Publication Activity Database

    Rackstraw, D.S.; Ciricosta, O.; Vinko, S.M.; Barbrel, B.; Burian, Tomáš; Chalupský, Jaromír; Cho, B.I.; Chung, H.-K.; Dakovski, G.L.; Engelhorn, K.; Hájková, Věra; Heimann, P.; Holmes, M.; Juha, Libor; Krzywinski, J.; Lee, R. W.; Toleikis, S.; Turner, J.J.; Zastrau, U.; Wark, J. S.

    2015-01-01

    Roč. 114, č. 1 (2015), "015003-1"-"015003-5" ISSN 0031-9007 R&D Projects: GA ČR(CZ) GA14-29772S; GA MŠk(CZ) LG13029 Grant - others:AVČR(CZ) M100101221 Institutional support: RVO:68378271 Keywords : free electron laser * x-ray * ionization of plasmas Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 7.645, year: 2015

  18. X-ray diagnostics in the laser-initiated fusion program

    International Nuclear Information System (INIS)

    Godwin, R.P.

    1975-08-01

    The high-density and high-temperature plasma conditions required for successful laser-initiated fusion make x-ray diagnostics a valuable tool in this exciting field. Measurements of the hard x-ray continuum emitted from laser targets provide insight into the complex laser-plasma coupling physics and the consequent energy transport through the bremsstrahlung signature of energetic electrons. X-ray techniques are important in the selection and assay of microballoon targets for current compression experiments. X-ray imaging experiments and diffraction spectroscopy of highly stripped atoms can provide information upon the symmetry, density and temperature of laser targets. Extremely high temporal and spatial resolution may be required for definitive diagnostic information on compressed targets. While laser-produced plasmas are interesting as possible intense x-ray sources and as a possible means of achieving x-ray lasing, those topics are outside the scope of this review. (auth)

  19. Spectral and imaging characterization of tabletop X-ray lasers

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, J.; Osterheld, A.L.; Moon, S.J.; Fournier, K.B.; Nilsen, J. [Lawrence Livermore National Lab., CA (United States); Faenov, A.Ya.; Pikuz, T.A.; Skobelev, I.Yu.; Magunov, A.I. [Lawrence Livermore National Lab., CA (United States); MISDC of VNIIFTRI, Mendeleevo (Russian Federation); Shlyaptsev, V.N. [Lawrence Livermore National Lab., CA (United States); California Univ., Davis, CA (United States). DAS

    2001-07-01

    We have performed L-shell spectroscopy and one-dimensional (1-D) imaging of a line focus plasma from a laser-heated Fe polished slab using the tabletop COMET laser system at the Lawrence Livermore National Laboratory. These plasmas are used to generate a Ne-like Fe transient gain X-ray laser that is recorded simultaneously. A spherically-curved crystal spectrometer gives high resolution X-ray spectra of the n=3-2 and n=4-2 resonance lines with 1-D spatial resolution along the line focus. Spectra are presented for different laser pulse conditions. In addition, a variety of X-ray imaging techniques are described. We discuss imaging results from a double-slit X-ray camera with a spherically-curved crystal spectrometer. We show a high resolution Fe K-{alpha} spectrum from the X-ray laser target that indicates the presence of hot electrons in the X-ray laser plasma. (orig.)

  20. Ultra-short wavelength x-ray system

    Science.gov (United States)

    Umstadter, Donald [Ann Arbor, MI; He, Fei [Ann Arbor, MI; Lau, Yue-Ying [Potomac, MD

    2008-01-22

    A method and apparatus to generate a beam of coherent light including x-rays or XUV by colliding a high-intensity laser pulse with an electron beam that is accelerated by a synchronized laser pulse. Applications include x-ray and EUV lithography, protein structural analysis, plasma diagnostics, x-ray diffraction, crack analysis, non-destructive testing, surface science and ultrafast science.

  1. Compact gain saturated plasma based X-ray lasers down to 6.9nm

    Science.gov (United States)

    Rocca, Jorge; Wang, Y.; Wang, S.; Rockwood, A.; Berrill, M.; Shlyaptsev, V.

    2017-10-01

    Plasma based soft x-ray amplifiers allow many experiments requiring bright, high energy soft x-ray laser pulses to be conducted in compact facilities. We have extended the wavelength of compact gain saturated x-ray lasers to 6.89 nm in a Ni-like Gd plasma generated by a Ti:Sa laser. Gain saturated laser operation was also obtained at 7.36 nm in Ni-like Sm. Isolectronic scaling and optimization of laser pre-pulse duration allowed us to also observe strong lasing at 6.6 nm and 6.1 nm in Ni-like Tb, and amplification at 6.4 nm and 5.89 nm in Ni-like Dy. The results were obtained by transient laser heating of solid targets with traveling wave excitation at progressively increased gracing incidence angles. We show that the optimum pump angle of incidence for collisional Ni-like lasers increases linearly with atomic number from Z =42 to Z =66, reaching 43 degrees for Ni-like Dy, in good agreement with hydrodynamic/atomic physics simulations. These results will enable single-shot nano-scale imaging and other application of sub-7 nm lasers to be performed at compact facilities. Work supported by Grant DE-FG02-4ER15592 of the Department of Energy, Office of Science, and by the National Science Foundation Grant ECCS 1509925.

  2. Soft X-rays from the sunlit earth's atmosphere

    International Nuclear Information System (INIS)

    McKenzie, D.L.; Rugge, H.R.; Charles, P.A.

    1982-01-01

    The HEAO-1 A-2 experiment low energy proportional counters have been used to measure the X-ray spectrum of the sunlit earth in the energy range 0.2 to 0.8 keV. The X-rays arise by coherent scattering of, or fluorescence of atmospheric constituents by, solar coronal X-rays incident on the atmosphere. Although the relative spectral contributions of the two processes depend upon the sun-earth-satellite geometry, fluorescent oxygen and nitrogen K X-ray emission is always important. The observed spectra were compared with calculations in order to derive the coronal temperature and emission measure, parameters that characterize the incident solar spectrum. These derived parameters agree well with the expected values for the nonflaring sun, and good agreement was obtained between measurements closely spaced in time but having a wide range of geometries and counting rates. Thus X-ray observations of the sunlit earth's atmosphere can be a useful monitor of solar activity for satellite-borne instrumentation unable to view the sun directly. The total measured fluorescent line flux agreed well with calculations, but the N:O line ratio did not. This disagreement is attributed to several causes which are discussed. (author)

  3. Albedo of X-ray through the region of rarefaction wave

    International Nuclear Information System (INIS)

    Zhang Jun

    2001-01-01

    In the process of implosion indirectly driven by laser, the high temperature and low density plasma produced by X-ray ablation is in the state of non-local thermodynamic equilibrium. And the propagation of X-ray needs to be treated by transportation method. X-ray energy flow reflected by plasma depends on the density, temperature of radiation and electrons, and their space profiles if the plasma produced by ablation is fully ionized. In addition, the plasma parameters in the region of rarefaction wave is determined by means of a simplified model. The approach to compute X-ray albedo is presented and the analytical formulae of the albedo are given

  4. Soft X-ray spectrometer design for warm dense plasma measurements on DARHT Axis-I

    Energy Technology Data Exchange (ETDEWEB)

    Ramey, Nicholas Bryan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Perry, John Oliver [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Coleman, Joshua Eugene [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-07-11

    A preliminary design study is being performed on a soft X-ray spectrometer to measure K-shell spectra emitted by a warm dense plasma generated on Axis-I of the Dual-Axis Radiographic Hydrodynamic Testing (DARHT) facility at Los Alamos National Laboratory. The 100-ns-long intense, relativistic electron pulse with a beam current of 1.7 kA and energy of 19.8 MeV deposits energy into a thin metal foil heating it to a warm dense plasma. The collisional ionization of the target by the electron beam produces an anisotropic angular distribution of K-shell radiation and a continuum of both scattered electrons and Bremsstrahlung up to the beam energy of 19.8 MeV. The principal goal of this project is to characterize these angular distributions to determine the optimal location to deploy the soft X-ray spectrometer. In addition, a proof-of-principle design will be presented. The ultimate goal of the spectrometer is to obtain measurements of the plasma temperature and density to benchmark equation-of-state models of the warm dense matter regime.

  5. Glass sample preparation and performance investigations. [solar x-ray imager

    Science.gov (United States)

    Johnson, R. Barry

    1992-01-01

    This final report details the work performed under this delivery order from April 1991 through April 1992. The currently available capabilities for integrated optical performance modeling at MSFC for large and complex systems such as AXAF were investigated. The Integrated Structural Modeling (ISM) program developed by Boeing for the U.S. Air Force was obtained and installed on two DECstations 5000 at MSFC. The structural, thermal and optical analysis programs available in ISM were evaluated. As part of the optomechanical engineering activities, technical support was provided in the design of support structure, mirror assembly, filter wheel assembly and material selection for the Solar X-ray Imager (SXI) program. As part of the fabrication activities, a large number of zerodur glass samples were prepared in different sizes and shapes for acid etching, coating and polishing experiments to characterize the subsurface damage and stresses produced by the grinding and polishing operations. Various optical components for AXAF video microscope and the x-ray test facility were also fabricated. A number of glass fabrication and test instruments such as a scatter plate interferometer, a gravity feed saw and some phenolic cutting blades were fabricated, integrated and tested.

  6. The spectrometer/telescope for imaging X-rays on board the ESA Solar Orbiter spacecraft

    Czech Academy of Sciences Publication Activity Database

    Krucker, S.; Benz, A. O.; Hurford, G.J.; Arnold, N.G.; Orleanski, P.; Groebelbauer, H.-P.; Casadei, D.; Kobler, S.; Iseli, L.; Wiehl, H.J.; Fárník, František

    2013-01-01

    Roč. 732, December (2013), s. 295-298 ISSN 0168-9002. [Vienna Conference on Instrumentation /13./. Vienna, 11.02.2013-15.02.2013] Institutional support: RVO:67985815 Keywords : Fourier optics * X-ray imaging * solar flares Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics OBOR OECD: Astronomy (including astrophysics,space science) Impact factor: 1.316, year: 2013

  7. Soft X-ray beam induced current technique

    Energy Technology Data Exchange (ETDEWEB)

    Watts, B; Ade, H [Department of Physics, North Carolina State University, Raleigh, NC 27695 (United States); Queen, D; Hellman, F [Department of Physics, University of California, Berkeley, CA 94720 (United States); Kilcoyne, A L D; Tyliszczak, T, E-mail: benjamin.watts@gmail.co [Advanced Light Source, Lawrence Berkeley Nat. Lab., Berkeley, CA 94720 (United States)

    2009-09-01

    Direct mapping of the charge transport efficiency of polymer solar cell devices using a soft X-ray beam induced current (SoXBIC) method is described. By fabricating a polymer solar cell on an x-ray transparent substrate, we demonstrate the ability to map polymer composition and nanoscale structure within an operating solar cell device and to simultaneously measure the local charge transport efficiency via the short-circuit current. A simple model is calculated and compared to experimental SoXBIC data of a PFB:F8BT bulk-heterojunction device in order to gain greater insight into the device operation and physics.

  8. Development of X-ray photoelectron microscope with a compact X-ray source generated by line-focused laser irradiation

    International Nuclear Information System (INIS)

    Yamaguchi, N.; Takahashi, Z.; Nishimura, Y.; Watanabe, K.; Okamoto, Y.; Sakata, A.; Azuma, H.; Hara, T.

    2005-01-01

    A laboratory-sized X-ray photoelectron microscope was constructed using a compact X-ray source produced by line-focused laser irradiation. The system is a scanning type photoelectron microscope where X-ray beam is micro-focused via Schwarzschild optics. A compact laser-plasma X-ray source has been developed with a YAG laser, a line-focus lens assembly, an Al tape-target driver and a debris prevention system. The 13.1 nm X-ray was delivered along line plasma whose length was 0.6 or 11 mm with higher intensity than that from a point-focused source. The Schwarzschild optics having the designed demagnification of 224, which was coated with Mo/Si multilayers for 13.1 nm X-ray, was set on the beamline 1 m distant from the source. The electron energy analyser was a spherical capacitor analyser with the photoelectron image detection system that was suited for detection of vast photoelectrons excited by an X-ray pulse of ns-order duration. The spatial resolution less than 5 μm has been confirmed from the variation of As 3d electron intensity along the position of the GaAs sample coated with a photo-resist test pattern

  9. Soft X-ray images of the solar corona using normal incidence optics

    Science.gov (United States)

    Bruner, M. E.; Haisch, B. M.; Brown, W. A.; Acton, L. W.; Underwood, J. H.

    1988-01-01

    A solar coronal loop system has been photographed in soft X-rays using a normal incidence telescope based on multilayer mirror technology. The telescope consisted of a spherical objective mirror of 4 cm aperture and 1 m focal length, a film cassette, and a focal plane shutter. A metallized thin plastic film filter was used to exclude visible light. The objective mirror was covered with a multilayer coating consisting of alternating layers of tungsten and carbon whose combined thicknesses satisfied the Bragg diffraction condition for 44 A radiation. The image was recorded during a rocket flight on October 25, 1985 and was dominated by emission lines arising from the Si XII spectrum. The rocket also carried a high resolution soft X-ray spectrograph that confirmed the presence of Si XII line radiation in the source. This image represents the first successful use of multilayer technology for astrophysical observations.

  10. Probing electron acceleration and x-ray emission in laser-plasma accelerators

    International Nuclear Information System (INIS)

    Thaury, C.; Ta Phuoc, K.; Corde, S.; Brijesh, P.; Lambert, G.; Malka, V.; Mangles, S. P. D.; Bloom, M. S.; Kneip, S.

    2013-01-01

    While laser-plasma accelerators have demonstrated a strong potential in the acceleration of electrons up to giga-electronvolt energies, few experimental tools for studying the acceleration physics have been developed. In this paper, we demonstrate a method for probing the acceleration process. A second laser beam, propagating perpendicular to the main beam, is focused on the gas jet few nanosecond before the main beam creates the accelerating plasma wave. This second beam is intense enough to ionize the gas and form a density depletion, which will locally inhibit the acceleration. The position of the density depletion is scanned along the interaction length to probe the electron injection and acceleration, and the betatron X-ray emission. To illustrate the potential of the method, the variation of the injection position with the plasma density is studied

  11. MAGNETIC NON-POTENTIALITY OF SOLAR ACTIVE REGIONS AND PEAK X-RAY FLUX OF THE ASSOCIATED FLARES

    International Nuclear Information System (INIS)

    Tiwari, Sanjiv Kumar; Venkatakrishnan, P.; Gosain, Sanjay

    2010-01-01

    Predicting the severity of solar eruptive phenomena such as flares and coronal mass ejections remains a great challenge despite concerted efforts to do so over the past several decades. However, the advent of high-quality vector magnetograms obtained from Hinode (SOT/SP) has increased the possibility of meeting this challenge. In particular, the spatially averaged signed shear angle (SASSA) seems to be a unique parameter for quantifying the non-potentiality of active regions. We demonstrate the usefulness of the SASSA for predicting flare severity. For this purpose, we present case studies of the evolution of magnetic non-potentiality using 115 vector magnetograms of four active regions, namely, ARs NOAA 10930, 10960, 10961, and 10963 during 2006 December 8-15, 2007 June 3-10, 2007 June 28-July 5, and 2007 July 10-17, respectively. The NOAA ARs 10930 and 10960 were very active and produced X and M class flares, respectively, along with many smaller X-ray flares. On the other hand, the NOAA ARs 10961 and 10963 were relatively less active and produced only very small (mostly A- and B-class) flares. For this study, we have used a large number of high-resolution vector magnetograms obtained from Hinode (SOT/SP). Our analysis shows that the peak X-ray flux of the most intense solar flare emanating from the active regions depends on the magnitude of the SASSA at the time of the flare. This finding of the existence of a lower limit of the SASSA for a given class of X-ray flares will be very useful for space weather forecasting. We have also studied another non-potentiality parameter called the mean weighted shear angle (MWSA) of the vector magnetograms along with the SASSA. We find that the MWSA does not show such distinction as the SASSA for upper limits of the GOES X-ray flux of solar flares; however, both the quantities show similar trends during the evolution of all active regions studied.

  12. Calibration of a High Resolution X-ray Spectrometer for High-Energy-Density Plasmas on NIF

    Science.gov (United States)

    Kraus, B.; Gao, L.; Hill, K. W.; Bitter, M.; Efthimion, P.; Schneider, M. B.; Chen, H.; Ayers, J.; Beiersdorfer, P.; Liedahl, D.; Macphee, A. G.; Thorn, D. B.; Bettencourt, R.; Kauffman, R.; Le, H.; Nelson, D.

    2017-10-01

    A high-resolution, DIM-based (Diagnostic Instrument Manipulator) x-ray crystal spectrometer has been calibrated for and deployed at the National Ignition Facility (NIF) to diagnose plasma conditions and mix in ignition capsules near stagnation times. Two conical crystals in the Hall geometry focus rays from the Kr He- α, Ly- α, and He- β complexes onto a streak camera for time-resolved spectra, in order to measure electron density and temperature by observing Stark broadening and relative intensities of dielectronic satellites. Signals from these two crystals are correlated with a third crystal that time-integrates the intervening energy range. The spectrometer has been absolutely calibrated using a microfocus x-ray source, an array of CCD and single-photon-counting detectors, and K- and L-absorption edge filters. Measurements of the integrated reflectivity, energy range, and energy resolution for each crystal will be presented. The implications of the calibration on signal levels from NIF implosions and x-ray filter choices will be discussed. This work was performed under the auspices of the U.S. DoE by Princeton Plasma Physics Laboratory under contract DE-AC02-09CH11466 and by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344.

  13. The Ultraviolet Surprise. Efficient Soft X-Ray High Harmonic Generation in Multiply-Ionized Plasmas

    International Nuclear Information System (INIS)

    Popmintchev, Dimitar; Hernandez-Garcia, Carlos; Dollar, Franklin; Mancuso, Christopher; Perez-Hernandez, Jose A.; Chen, Ming-Chang; Hankla, Amelia; Gao, Xiaohui; Shim, Bonggu; Gaeta, Alexander L.; Tarazkar, Maryam; Romanov, Dmitri A.; Levis, Robert J.; Gaffney, Jim A.; Foord, Mark; Libby, Stephen B.; Jaron-Becker, Agnieskzka; Becker, Andreas; Plaja, Luis; Muranane, Margaret M.; Kapteyn, Henry C.; Popmintchev, Tenio

    2015-01-01

    High-harmonic generation is a universal response of matter to strong femtosecond laser fields, coherently upconverting light to much shorter wavelengths. Optimizing the conversion of laser light into soft x-rays typically demands a trade-off between two competing factors. Reduced quantum diffusion of the radiating electron wave function results in emission from each species which is highest when a short-wavelength ultraviolet driving laser is used. But, phase matching - the constructive addition of x-ray waves from a large number of atoms - favors longer-wavelength mid-infrared lasers. We identified a regime of high-harmonic generation driven by 40-cycle ultraviolet lasers in waveguides that can generate bright beams in the soft x-ray region of the spectrum, up to photon energies of 280 electron volts. Surprisingly, the high ultraviolet refractive indices of both neutral atoms and ions enabled effective phase matching, even in a multiply ionized plasma. We observed harmonics with very narrow linewidths, while calculations show that the x-rays emerge as nearly time-bandwidt-limited pulse trains of ~100 attoseconds

  14. Higher coherent x-ray laser

    International Nuclear Information System (INIS)

    Hasegawa, Noboru; Nagashima, Keisuke; Kawachi, Tetsuya

    2001-01-01

    X-ray lasers generated by an ultra short pulse laser have advantages such as monochromatic, short pulse duration, small beam divergence, high intensity, and coherence. Spatial coherence is most important for applications, we have investigated the transient collisional excitation (TCE) scheme x-ray laser lasing from Ne-like titanium (31.6 nm), Ne-like silver (13.9 nm) and tin (11.9 nm). However, the spatial coherence was not so good with this scheme. We have been studying to improve the spatial coherence of the x-ray laser and have proposed to use coherent seed light tuned to the x-ray laser wavelength generated from higher harmonics generation (HHG), which is introduced to the x-ray laser medium (Ne-like titanium, Ni-like silver plasmas). We present about the theoretical study of the coupling efficiency HHG light with x-ray laser medium. (author)

  15. STELLAR CORONAE, SOLAR FLARES: A DETAILED COMPARISON OF {sigma} GEM, HR 1099, AND THE SUN IN HIGH-RESOLUTION X-RAYS

    Energy Technology Data Exchange (ETDEWEB)

    Huenemoerder, David P. [Massachusetts Institute of Technology, Kavli Institute for Astrophysics and Space Research, 70 Vassar St., Cambridge, MA 02139 (United States); Phillips, Kenneth J. H. [Visiting Scientist, Space Research Center, Polish Academy of Sciences, 51-622, Kopernika 11, Wroclaw (Poland); Sylwester, Janusz; Sylwester, Barbara, E-mail: dph@space.mit.edu, E-mail: kennethjhphillips@yahoo.com, E-mail: js@cbk.pan.wroc.pl, E-mail: bs@cbk.pan.wroc.pl [Space Research Center, Polish Academy of Sciences, 51-622, Kopernika 11, Wroclaw (Poland)

    2013-05-10

    The Chandra High Energy Transmission Grating Spectrometer (HETG) spectra of the coronally active binary stars {sigma} Gem and HR 1099 are among the highest fluence observations for such systems taken at high spectral resolution in X-rays with this instrument. This allows us to compare their properties in detail to solar flare spectra obtained with the Russian CORONAS-F spacecraft's RESIK instrument at similar resolution in an overlapping bandpass. Here we emphasize the detailed comparisons of the 3.3-6.1 A region (including emission from highly ionized S, Si, Ar, and K) from solar flare spectra to the corresponding {sigma} Gem and HR 1099 spectra. We also model the larger wavelength range of the HETG, from 1.7 to 25 A - having emission lines from Fe, Ca, Ar, Si, Al, Mg, Ne, O, and N-to determine coronal temperatures and abundances. {sigma} Gem is a single-lined coronally active long-period binary which has a very hot corona. HR 1099 is a similar, but shorter period, double-lined system. With very deep HETG exposures we can even study emission from some of the weaker species, such as K, Na, and Al, which are important since they have the lowest first ionization potentials, a parameter well known to be correlated with elemental fractionation in the solar corona. The solar flare temperatures reach Almost-Equal-To 20 MK, comparable to the {sigma} Gem and HR 1099 coronae. During the Chandra exposures, {sigma} Gem was slowly decaying from a flare and its spectrum is well characterized by a collisional ionization equilibrium plasma with a broad temperature distribution ranging from 2 to 60 MK, peaking near 25 MK, but with substantial emission from 50 MK plasma. We have detected K XVIII and Na XI emission which allow us to set limits on their abundances. HR 1099 was also quite variable in X-rays, also in a flare state, but had no detectable K XVIII. These measurements provide new comparisons of solar and stellar coronal abundances, especially at the lowest first

  16. Hard x ray imaging and the relative contribution of thermal and nonthermal emission in flares

    International Nuclear Information System (INIS)

    Holman, G.D.

    1986-01-01

    The question of whether the impulsive 25 to 100 keV x ray emission from solar flares is thermal or nonthermal has been a long-standing controversy. Both thermal and nonthermal (beam) models have been developed and applied to the hard x ray data. It now seems likely that both thermal and nonthermal emission have been observed at hard x ray energies. The Hinotori classification scheme, for example, is an attempt to associate the thermal-nonthermal characteristics of flare hard x ray emission with other flare properties. From a theoretical point of view, it is difficult to generate energetic, nonthermal electrons without dumping an equal or greater amount of energy into plasma heating. On the other hand, any impulsive heating process will invariably generate at least some nonthermal particles. Hence, strictly speaking, although thermal or nonthermal emission may dominate the hard x ray emission in a given energy range for a given flare, there is no such thing as a purely thermal or nonthermal flare mechanism

  17. Laboratory Studies of X-ray Spectra Formed by Charge Exchange

    Science.gov (United States)

    Beiersdorfer, Peter; Ali, R.; Brown, G. V.; Koutroumpa, D.; Kelley, R. L.; Kilbourne, C.; Leutenegger, M. A.; Porter, F.

    2013-04-01

    Charge exchange between ions and neutral atoms or molecules has been accepted at an important soft producing process in our solar system. By extension, charge exchange may contribute to the X-ray emission of circumstellar material. It may also produce X-ray emission at the boundaries of supernova ejecta and star burst galaxies, or whenever hot plasma collides with neutral matter. X-ray spectra of K-shell and L-shell ions formed by charge exchange have now been studied in a variety of laboratory settings. These experiments have shown several characteristic features of line formation by charge exchange when compared to the X-ray emission produced by electron-impact excitation, e.g., enhancement emission of forbidden lines and of lines from levels with high principal quantum number. They have also shown a dependence on the interaction gas and on the energy of the ion-neutral collision. Moreover, the transfer of multiple electrons is typically preferred, provided the donor molecules or atoms have multiple valence-shell electrons. The laboratory measurements are in qualitative agreement with theory. However, the details of the observed X-ray spectra, especially those recorded with high spectral resolution, can differ substantially from predictions, especially for spectra produced at collision velocities equal to or lower than those found in thermal plasmas or produced with neutral gases other than atomic hydrogen. Puzzling discrepancies can be noted, such as enhanced emission from an upper level with the 'wrong' principal quantum number. Even more puzzling is a recent experiment in which two, co-mixed bare ion species of similar atomic number produce very different Lyman series emission upon charge exchange with a given neutral gas, defying both theoretical predictions and empirical scaling. Laboratory measurements have also shown that some of the characteristic features of charge exchange can be reproduced by radiative electron capture, i.e., by capture of a continuum

  18. Non-thermal Power-Law Distributions in Solar and Space Plasmas

    Science.gov (United States)

    Oka, M.; Battaglia, M.; Birn, J.; Chaston, C. C.; Effenberger, F.; Eriksson, E.; Fletcher, L.; Hatch, S.; Imada, S.; Khotyaintsev, Y. V.; Kuhar, M.; Livadiotis, G.; Miyoshi, Y.; Retino, A.

    2017-12-01

    Particles are accelerated to very high, non-thermal energies in solar and space plasma environments. While energy spectra of accelerated particles often exhibit a power-law and are characterized by the power-law index δ, it remains unclear how particles are accelerated to high energies and how δ is determined. Here, we review previous observations of the power-law index δ in a variety of different plasma environments with a particular focus on sub-relativistic electrons. It appears that in regions more closely related to magnetic reconnection (such as the "above-the-looptop" solar hard X-ray source and the plasma sheet in Earth's magnetotail), the spectra are typically soft (δ> 4). This is in contrast to the typically hard spectra (δuniform in the plasma sheet, while power-law distributions still exist even in quiet times. The role of magnetotail reconnection in the electron power-law formation could therefore be confounded with these background conditions. Because different regions have been studied with different instrumentations and methodologies, we point out a need for more systematic and coordinated studies of power-law distributions for a better understanding of possible scaling laws in particle acceleration as well as their universality.

  19. Soft x-ray measurements from the PDX tokamak

    International Nuclear Information System (INIS)

    Silver, E.H.; Bitter, M.; Brau, K.; Eames, D.; Greenberger, A.; Hill, K.W.; Meade, D.M.; Roney, W.; Sauthoff, N.R.; von Goeler, S.

    1982-05-01

    Temporally and spatially-resolved profiles of the PDX soft x-ray spectra have been measured during single tokamak pulses of circular and divertor plasmas with a recently developed pulse height analyzer. This detection system incorporates an array of five vertically displaced sets of lithium-drifted silicon detectors, each consisting of three independent channels optimized for rapid data collection in adjacent energy regions. Simultaneous measurement of x-ray emission integrated along five chords of the plasma cross section can thereby be achieved. Abel inversion of these data yields temporally-resolved radial profiles of the local electron temperature from the slope of the continuum, concentrations of high-Z impurities from the characteristic line intensities, and a measure of Z/sub eff/ from the continuum intensity. The techniques of x-ray pulse height analysis, with illustrations featuring the results from the initial PDX circular plasma experiments are discussed in detail. In addition, comparisons between circular and divertor plasmas on PDX, derived from the x-ray measurements, are also presented

  20. NuSTAR Hard X-Ray Observation of a Sub-A Class Solar Flare

    Energy Technology Data Exchange (ETDEWEB)

    Glesener, Lindsay [School of Physics and Astronomy, University of Minnesota, Minneapolis (United States); Krucker, Säm; Hudson, Hugh [Space Sciences Laboratory, University of California at Berkeley, Berkeley (United States); Hannah, Iain G. [SUPA School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Grefenstette, Brian W. [Cahill Center for Astrophysics, California Institute of Technology, Pasadena (United States); White, Stephen M. [Air Force Research Laboratory, Albuquerque (United States); Smith, David M.; Marsh, Andrew J. [Santa Cruz Institute of Particle Physics and Department of Physics, University of California at Santa Cruz, Santa Cruz (United States)

    2017-08-20

    We report a Nuclear Spectroscopic Telescope Array ( NuSTAR ) observation of a solar microflare, SOL2015-09-01T04. Although it was too faint to be observed by the GOES X-ray Sensor, we estimate the event to be an A0.1 class flare in brightness. This microflare, with only ∼5 counts s{sup −1} detector{sup −1} observed by the Reuven Ramaty High Energy Solar Spectroscopic Imager ( RHESSI ), is fainter than any hard X-ray (HXR) flare in the existing literature. The microflare occurred during a solar pointing by the highly sensitive NuSTAR astrophysical observatory, which used its direct focusing optics to produce detailed HXR microflare spectra and images. The microflare exhibits HXR properties commonly observed in larger flares, including a fast rise and more gradual decay, earlier peak time with higher energy, spatial dimensions similar to the RHESSI microflares, and a high-energy excess beyond an isothermal spectral component during the impulsive phase. The microflare is small in emission measure, temperature, and energy, though not in physical size; observations are consistent with an origin via the interaction of at least two magnetic loops. We estimate the increase in thermal energy at the time of the microflare to be 2.4 × 10{sup 27} erg. The observation suggests that flares do indeed scale down to extremely small energies and retain what we customarily think of as “flare-like” properties.

  1. Wire number doubling in plasma-shell regime increases z-accelerator x-ray power

    International Nuclear Information System (INIS)

    Sanford, T.W.L.; Spielman, R.B.; Chandler, G.A.

    1997-11-01

    Doubling the number of tungsten wires from 120 to 240, keeping the mass fixed, increased the radiated x-ray power relative to the electrical power at the insulator stack of the z accelerator by (40±20)% for 8.75- and 20-mm-radii z-pinch wire arrays. Radiation-magneto-hydrodynamic calculations suggest that the arrays were operating in the 'plasma shell' regime, where the plasmas generated by the individual wires merge prior to the inward implosion of the entire array

  2. Wire number doubling in plasma-shell regime increases Z-accelerator X-ray power

    International Nuclear Information System (INIS)

    Sanford, T.W.L.; Spielman, R.B.; Chandler, G.A.

    1997-01-01

    Doubling the number of tungsten wires from 120 to 240, keeping the mass fixed, increased the radiated x-ray power relative to the electrical power at the insulator stack of the z accelerator by (40 ± 20)% for 8.75- and 20-mm-radii z-pinch wire arrays. Radiation-magneto-hydrodynamic calculations suggest that the arrays were operating in the plasma shell regime, where the plasma generated by the individual wires merge prior to the inward implosion of the entire array

  3. Wire number doubling in plasma-shell regime increases Z-accelerator X-ray power

    Energy Technology Data Exchange (ETDEWEB)

    Sanford, T.W.L.; Spielman, R.B.; Chandler, G.A. [and others

    1997-12-01

    Doubling the number of tungsten wires from 120 to 240, keeping the mass fixed, increased the radiated x-ray power relative to the electrical power at the insulator stack of the z accelerator by (40 {+-} 20)% for 8.75- and 20-mm-radii z-pinch wire arrays. Radiation-magneto-hydrodynamic calculations suggest that the arrays were operating in the plasma shell regime, where the plasma generated by the individual wires merge prior to the inward implosion of the entire array.

  4. Flare Characteristics from X-ray Light Curves

    Science.gov (United States)

    Gryciuk, M.; Siarkowski, M.; Sylwester, J.; Gburek, S.; Podgorski, P.; Kepa, A.; Sylwester, B.; Mrozek, T.

    2017-06-01

    A new methodology is given to determine basic parameters of flares from their X-ray light curves. Algorithms are developed from the analysis of small X-ray flares occurring during the deep solar minimum of 2009, between Solar Cycles 23 and 24, observed by the Polish Solar Photometer in X-rays (SphinX) on the Complex Orbital Observations Near-Earth of Activity of the Sun-Photon (CORONAS- Photon) spacecraft. One is a semi-automatic flare detection procedure that gives start, peak, and end times for single ("elementary") flare events under the assumption that the light curve is a simple convolution of a Gaussian and exponential decay functions. More complex flares with multiple peaks can generally be described by a sum of such elementary flares. Flare time profiles in the two energy ranges of SphinX (1.16 - 1.51 keV, 1.51 - 15 keV) are used to derive temperature and emission measure as a function of time during each flare. The result is a comprehensive catalogue - the SphinX Flare Catalogue - which contains 1600 flares or flare-like events and is made available for general use. The methods described here can be applied to observations made by Geosynchronous Operational Environmental Satellites (GOES), the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and other broad-band spectrometers.

  5. Investigation of solar flares in X-ray and optical spectral region

    International Nuclear Information System (INIS)

    Kurt, V.; Kurochka, L.N.; Zenchenko, V.M.

    1989-01-01

    Measurements of hard X h radiation of 180 solar flares carried out on board of the space probes Venera-13,-14, were compared with measurements of optical and thermal X t radiation. Values of total energy release during a flare in these regions are calculated, and correlation analysis is carried out. The bond correlations found have shown that total energy of fast electrons, caused X h -flare in the flare pulse phase, and thermal energy at the end of a pulse phase are practically connected with each othesr functionally. Quantitative connection between a flare ball in H α -line and the most probable energy values, being in different radiation regions calculated in the scope of generally accepted models, is established. The total energy of an optical (cold) part of the flare, radiation energy in X-ray region and the energy introduced to the flare volume by energy particles are shown to be compared between each other

  6. Soft X-ray measurements for investigating the plasma focus dynamics

    International Nuclear Information System (INIS)

    Nahrath, B.

    In a Mather-type plasma focus short time soft x-ray pictures are taken by means of a double pinhole camera equipped with a pulsed channel plate and two different filters to study the local development of electron temperatures Tsub(e) with time resolution of 3 ns. Up to the maximum compression the measured Tsub(e) are roughly in accordance with the results of MHD-calculations. During a later phase, characterized by the occurence of m=O-instabilities, localized plasma regions with high densities and high electron temperatures Tsub(e) of about 600 eV (up to 1000 eV) are observed. Using the channel plate technique with increased sensivity a slowly decaying plasma with local Tsub(e)-values of about 300 eV and large diffuse structures is identified for several hundred nanoseconds. During this 'late phase' of the focus most of the neutron emission takes place. There is no correlation between the value of Tsub(e) and the rate of neutron emission. (orig.) [de

  7. A New Observation of the Quiet Sun Soft X-ray (0.5-5 keV) Spectrum

    Science.gov (United States)

    Caspi, Amir; Woods, Thomas N.; Stone, Jordan

    2013-03-01

    The solar corona is the brightest source of X-rays in the solar system, and the X-ray emission is highly variable with solar activity. While this is particularly true during solar flares, when emission can be enhanced by many orders of magnitude up to gamma-ray energies, even the so-called "quiet Sun" is bright in soft X-rays (SXRs), as the 1-2 MK ambient plasma of the corona emits significant thermal bremsstrahlung up to 5 keV. However, the actual solar SXR (0.5-5 keV) spectrum is not well known, particularly during quiet periods, as, with few exceptions, this energy range has not been systematically studied in many years. Previous observations include ultra-high-resolution but very narrow-band spectra from crystral spectrometers (e.g. Yohkoh/BCS), or integrated broadband irradiances from photometers (e.g. GOES/XRS, TIMED/XPS, etc.) that lack detailed spectral information. In recent years, broadband measurements with fair energy resolution ( 0.5-0.7 keV FWHM) were made by SphinX on CORONAS-Photon and XRS on MESSENGER, although they did not extend below 1 keV. We present observations of the quiet Sun SXR emission obtained using a new SXR spectrometer flown on the third SDO/EVE underflight calibration rocket (NASA 36.286). The commercial off-the-shelf Amptek X123 silicon drift detector, with an 8-micron Be window and custom aperture, measured the solar SXR emission from 0.5 to >10 keV with 0.15 keV FWHM resolution (though, due to hardware limitations, with only 0.12 keV binning) and 2-sec cadence over 5 minutes on 23 June 2012. Despite the rising solar cycle, activity on 23 June 2012 was abnormally low, with no visible active regions and GOES XRS emission near 2010 levels; we measured no solar counts above 4 keV during the observation period. We compare our X123 measurements with spectra and broadband irradiances from other instruments, including the SphinX observations during the deep solar minimum of 2009, and with upper limits of >3 keV quiet Sun emission

  8. Polarization and spectral features of the hard x-ray continuum from non-thermal plasmas

    International Nuclear Information System (INIS)

    Hesse, M.; Platz, P.

    1989-12-01

    Starting from the cross-sections for the free-free radiation obtained within the relativistic Born-Elwert theory, we calculate the spectral and polarization properties of the hard X-ray continuum (hν > 50 KeV) for plasmas containing fast electrons with an anisotropic velocity distribution. The physical and geometrical quantities of our model are oriented towards the future lower-hybrid current drive (LHCD) experiments on Tore-Supra. Our parameter space covers parallel and perpendicular temperatures, the nuclear charge of the ions (mainly Z = 14 and 28), the cut-off energy of the electrons, the radial current profile and the viewing angle. Extensive calculations open on the optimum conditions for polarization measurements and also give guide-lines for the quantitative interpretation of data under real plasma conditions. A second part of this report will treat with the operational principles and expected performances of hard X-ray polarimeters

  9. Multilayer X-ray imaging systems

    Science.gov (United States)

    Shealy, D. L.; Hoover, R. B.; Gabardi, D. R.

    1986-01-01

    An assessment of the imaging properties of multilayer X-ray imaging systems with spherical surfaces has been made. A ray trace analysis was performed to investigate the effects of using spherical substrates (rather than the conventional paraboloidal/hyperboloidal contours) for doubly reflecting Cassegrain telescopes. These investigations were carried out for mirrors designed to operate at selected soft X-ray/XUV wavelengths that are of significance for studies of the solar corona/transition region from the Stanford/MSFC Rocket X-Ray Telescope. The effects of changes in separation of the primary and secondary elements were also investigated. These theoretical results are presented as well as the results of ray trace studies to establish the resolution and vignetting effects as a function of field angle and system parameters.

  10. CO-ANALYSIS OF SOLAR MICROWAVE AND HARD X-RAY SPECTRAL EVOLUTIONS. I. IN TWO FREQUENCY OR ENERGY RANGES

    International Nuclear Information System (INIS)

    Song Qiwu; Huang Guangli; Nakajima, Hiroshi

    2011-01-01

    Solar microwave and hard X-ray spectral evolutions are co-analyzed in the 2000 June 10 and 2002 April 10 flares, and are simultaneously observed by the Owens-Valley Solar Array in the microwave band and by Yohkoh/Hard X-ray Telescope or RHESSI in the hard X-ray band, with multiple subpeaks in their light curves. The microwave and hard X-ray spectra are fitted by a power law in two frequency ranges of the optical thin part and two photon energy ranges, respectively. Similar to an earlier event in Shao and Huang, the well-known soft-hard-soft pattern of the lower energy range changed to the hard-soft-hard (HSH) pattern of the higher energy range during the spectral evolution of each subpeak in both hard X-ray flares. This energy dependence is actually supported by a positive correlation between the overall light curves and spectral evolution in the lower energy range, while it becomes an anti-correlation in the higher energy range. Regarding microwave data, the HSH pattern appears in the spectral evolution of each subpeak in the lower frequency range, which is somewhat similar to Huang and Nakajima. However, it returns back to the well-known pattern of soft-hard-harder for the overall spectral evolution in the higher frequency range of both events. This frequency dependence is confirmed by an anti-correlation between the overall light curves and spectral evolution in the lower frequency range, but it becomes a positive correlation in the higher frequency range. The possible mechanisms are discussed, respectively, for reasons why hard X-ray and microwave spectral evolutions have different patterns in different energy and frequency intervals.

  11. Serial data acquisition for the X-ray plasma diagnostics with selected GEM detector structures

    Science.gov (United States)

    Czarski, T.; Chernyshova, M.; Pozniak, K. T.; Kasprowicz, G.; Zabolotny, W.; Kolasinski, P.; Krawczyk, R.; Wojenski, A.; Zienkiewicz, P.

    2015-10-01

    The measurement system based on GEM—Gas Electron Multiplier detector is developed for X-ray diagnostics of magnetic confinement tokamak plasmas. The paper is focused on the measurement subject and describes the fundamental data processing to obtain reliable characteristics (histograms) useful for physicists. The required data processing have two steps: 1—processing in the time domain, i.e. events selections for bunches of coinciding clusters, 2—processing in the planar space domain, i.e. cluster identification for the given detector structure. So, it is the software part of the project between the electronic hardware and physics applications. The whole project is original and it was developed by the paper authors. The previous version based on 1-D GEM detector was applied for the high-resolution X-ray crystal spectrometer KX1 in the JET tokamak. The current version considers 2-D detector structures for the new data acquisition system. The fast and accurate mode of data acquisition implemented in the hardware in real time can be applied for the dynamic plasma diagnostics. Several detector structures with single-pixel sensors and multi-pixel (directional) sensors are considered for two-dimensional X-ray imaging. Final data processing is presented by histograms for selected range of position, time interval and cluster charge values. Exemplary radiation source properties are measured by the basic cumulative characteristics: the cluster position distribution and cluster charge value distribution corresponding to the energy spectra. A shorter version of this contribution is due to be published in PoS at: 1st EPS conference on Plasma Diagnostics

  12. Serial data acquisition for the X-ray plasma diagnostics with selected GEM detector structures

    International Nuclear Information System (INIS)

    Czarski, T.; Chernyshova, M.; Pozniak, K.T.; Kasprowicz, G.; Zabolotny, W.; Kolasinski, P.; Krawczyk, R.; Wojenski, A.; Zienkiewicz, P.

    2015-01-01

    The measurement system based on GEM—Gas Electron Multiplier detector is developed for X-ray diagnostics of magnetic confinement tokamak plasmas. The paper is focused on the measurement subject and describes the fundamental data processing to obtain reliable characteristics (histograms) useful for physicists. The required data processing have two steps: 1—processing in the time domain, i.e. events selections for bunches of coinciding clusters, 2—processing in the planar space domain, i.e. cluster identification for the given detector structure. So, it is the software part of the project between the electronic hardware and physics applications. The whole project is original and it was developed by the paper authors. The previous version based on 1-D GEM detector was applied for the high-resolution X-ray crystal spectrometer KX1 in the JET tokamak. The current version considers 2-D detector structures for the new data acquisition system. The fast and accurate mode of data acquisition implemented in the hardware in real time can be applied for the dynamic plasma diagnostics. Several detector structures with single-pixel sensors and multi-pixel (directional) sensors are considered for two-dimensional X-ray imaging. Final data processing is presented by histograms for selected range of position, time interval and cluster charge values. Exemplary radiation source properties are measured by the basic cumulative characteristics: the cluster position distribution and cluster charge value distribution corresponding to the energy spectra. A shorter version of this contribution is due to be published in PoS at: 1 st EPS conference on Plasma Diagnostics

  13. Determination of Fe charge-state distributions in PLT by Bragg crystal x-ray spectroscopy

    International Nuclear Information System (INIS)

    Hill, K.W.; von Goeler, S.; Bitter, M.

    1978-08-01

    A curved-crystal Bragg x-ray spectrometer has been used to measure Kα or 1s-2p radiation from highly stripped Fe XVIII to Fe XXV impurity ions in the PLT tokamak. The spectrometer has sufficient energy resolution (approximately < 4 eV at 6400 eV) to distinguish between the different ionization states of iron by measuring the energy shift of the Kα x rays. The measured wavelengths agree well with theory and with spectra from solar flares and from laser-produced plasmas. The distribution of Fe charge states in the center of the discharge has been inferred from a comparison of the measured x-ray spectrum with theory. The shape of the spectrum depends strongly on electron temperature (T/sub e/) in the range T/sub e/ = 800 to 1500 eV. Within the factor of two uncertainty in L-shell ionization cross sections, measured intensities agree with theory, which is based on coronal equilibrium, indicating that the ion life-time in the center of the plasma is approximately equal to or greater than the equilibration time

  14. Assessment of image quality in x-ray radiography imaging using a small plasma focus device

    Science.gov (United States)

    Kanani, A.; Shirani, B.; Jabbari, I.; Mokhtari, J.

    2014-08-01

    This paper offers a comprehensive investigation of image quality parameters for a small plasma focus as a pulsed hard x-ray source for radiography applications. A set of images were captured from some metal objects and electronic circuits using a low energy plasma focus at different voltages of capacitor bank and different pressures of argon gas. The x-ray source focal spot of this device was obtained to be about 0.6 mm using the penumbra imaging method. The image quality was studied by several parameters such as image contrast, line spread function (LSF) and modulation transfer function (MTF). Results showed that the contrast changes by variations in gas pressure. The best contrast was obtained at a pressure of 0.5 mbar and 3.75 kJ stored energy. The results of x-ray dose from the device showed that about 0.6 mGy is sufficient to obtain acceptable images on the film. The measurements of LSF and MTF parameters were carried out by means of a thin stainless steel wire 0.8 mm in diameter and the cut-off frequency was obtained to be about 1.5 cycles/mm.

  15. Search for Thermal X-ray Features from the Crab nebula with Hitomi Soft X-ray Spectrometer

    Science.gov (United States)

    Tsujimoto, M.; Mori, K.; Lee, S.; Yamaguchi, H.; Tominaga, N.; Moriya, T.; Sato, T.; Bamba, A.

    2017-10-01

    The Crab nebula originates from a core-collapse SN in 1054. It has an anomalously low observed ejecta mass for a Fe-core collapse SN. Intensive searches were made for an undetected massive shell to solve this discrepancy. An alternative idea is that the SN1054 is an electron-capture (EC) explosion with a lower explosion energy than Fe-core collapse SNe. In the X-rays, imaging searches were performed for the plasma emission from the shell in the Crab outskirts. However, the extreme brightness hampers access to its vicinity. We used spectroscopic technique using the X-ray micro-calorimeter onboard Hitomi. We searched for the emission or absorption features by the thermal plasma and set a new limit. We re-evaluated the existing data to claim that the X-ray plasma mass is wind). We found that the observed mass limit can be compatible with both SN models if the environment has a low density of wind density parameter for the wind environment.

  16. X-ray sources by Z-pinch for inertial confinement fusion

    International Nuclear Information System (INIS)

    Akiyama, Hidenori; Katsuki, Sunao; Lisitsyn, Igor

    1999-01-01

    Inertial confinement nuclear fusion driven by X-ray from Z-pinch plasmas has been developed. Recently, extremely high X-ray power (290 TW) and energy (1.8 MJ) were produced in fast Z-pinch implosions on the Z accelerator (Sandia National Laboratories). Wire arrays are used to produce the initial plasma. The X-ray from Z-pinch plasmas produced by pulsed power has great potential as a driver of inertial confinement nuclear fusion. (author)

  17. Investigation of Energy Release in Microflares Observed by the Second Sounding Rocket Flight of the Focusing Optics X-ray Solar Imager (FOXSI-2)

    Science.gov (United States)

    Vievering, J. T.; Glesener, L.; Panchapakesan, S. A.; Ryan, D.; Krucker, S.; Christe, S.; Buitrago-Casas, J. C.; Inglis, A. R.; Musset, S.

    2017-12-01

    Observations of the Sun in hard x-rays can provide insight into many solar phenomena which are not currently well-understood, including the mechanisms behind particle acceleration in flares. RHESSI is the only solar-dedicated imager currently operating in the hard x-ray regime. Though RHESSI has greatly added to our knowledge of flare particle acceleration, the indirect imaging method of rotating collimating optics is fundamentally limited in sensitivity and dynamic range. By instead using a direct imaging technique, the structure and evolution of even small flares and active regions can be investigated in greater depth. FOXSI (Focusing Optics X-ray Solar Imager), a hard x-ray instrument flown on two sounding rocket campaigns, seeks to achieve these improved capabilities by using focusing optics for solar observations in the 4-20 keV range. During the second of the FOXSI flights, flown on December 11, 2014, two microflares were observed, estimated as GOES class A0.5 and A2.5 (upper limits). Here we present current imaging and spectral analyses of these microflares, exploring the nature of energy release and comparing to observations from other instruments. Additionally, we feature the first analysis of data from the FOXSI-2 CdTe strip detectors, which provide improved efficiency above 10 keV. Through this analysis, we investigate the capabilities of FOXSI in enhancing our knowledge of smaller-scale solar events.

  18. X-ray emission from a high-atomic-number z-pinch plasma created from compact wire arrays

    International Nuclear Information System (INIS)

    Sanford, T.W.L.; Mosher, D.; De Groot, J.S.

    1996-01-01

    Thermal and nonthermal x-ray emission from the implosion of compact tungsten wire arrays in 5-MA Saturn discharges is reported. The timing of multiple implosions and the thermal x-ray spectra (1 to 10 keV) agree with 2D radiation-hydrocode simulations. Nonthermal x-ray emission (10 to 100 keV) correlates with pinch spots distributed along the z-axis. The similarities of the measured nonthermal spectrum, yield, and pinch-spot emission with those of 0.8-MA, single-exploded-wire discharges on Gamble-II suggest a common nonthermal-production mechanism. Nonthermal x-ray yields are lower than expected from current scaling of Gamble II results, suggesting that implosion geometries are not as efficient as single-wire geometries for nonthermal x-ray production. The instabilities, azimuthal asymmetries, and inferred multiple implosions that accompany the implosion geometry lead to larger, more irregular pinch spots, a likely reason for reduced nonthermal efficiency. A model for nonthermal-electron acceleration across magnetic fields in highly-collisional, high-atomic-number plasmas combined with 1D hydrocode simulations of Saturn compact loads predicts weak nonthermal x-ray emission. (author). 3 figs., 10 refs

  19. X-ray emission from a high-atomic-number z-pinch plasma created from compact wire arrays

    International Nuclear Information System (INIS)

    Sanford, T.W.L.; Mosher, D.; De Groot, J.S.

    1996-01-01

    Thermal and nonthermal x-ray emission from the implosion of compact tungsten wire arrays in 5-MA Saturn discharges is reported. The timing of multiple implosions and the thermal x-ray spectra (1 to 10 keV) agree with 2D radiation-hydrocode simulations. Nonthermal x-ray emission (10 to 100 keV) correlates with pinch spots distributed along the z-axis. The similarities of the measured nonthermal spectrum, yield, and pinch-spot emission with those of 0.8-MA, single- exploded-wire discharges on Gamble-II suggest a common nonthermal- production mechanism. Nonthermal x-ray yields are lower than expected from current scaling of Gamble II results, suggesting that implosion geometries are not as efficient as single-wire geometries for nonthermal x-ray production. The instabilities, azimuthal asymmetries, and inferred multiple implosions that accompany the implosion geometry lead to larger, more irregular pinch spots, a likely reason for reduced nonthermal efficiency. A model for nonthermal-electron acceleration across magnetic fields in highly- collisional, high-atomic-number plasmas combined with 1D hydrocode simulations of Saturn compact loads predicts weak nonthermal x-ray emission

  20. Caliste-SO X-ray micro-camera for the STIX instrument on-board Solar Orbiter space mission

    International Nuclear Information System (INIS)

    Meuris, A.; Hurford, G.; Bednarzik, M.; Limousin, O.; Gevin, O.; Le Mer, I.; Martignac, J.; Horeau, B.; Grimm, O.; Resanovic, R.; Krucker, S.; Orleański, P.

    2012-01-01

    The Spectrometer Telescope for Imaging X-rays (STIX) is an instrument on the Solar-Orbiter space mission that performs hard X-ray imaging spectroscopy of solar flares. It consists of 32 collimators with grids and 32 spectrometer units called Caliste-SO for indirect Fourier-transform imaging. Each Caliste-SO device integrates a 1 cm 2 CdTe pixel sensor with a low-noise low-power analog front-end ASIC and circuits for supply regulation and filtering. The ASIC named IDeF-X HD is designed by CEA/Irfu (France) whereas CdTe-based semiconductor detectors are provided by the Laboratory for Micro- and Nanotechnology, Paul Scherrer Institute (Switzerland). The design of the hybrid, based on 3D Plus technology (France), is well suited for STIX spectroscopic requirements (1 keV FWHM at 6 keV, 4 keV low-level threshold) and system constraints (4 W power and 5 kg mass). The performance of the sub-assemblies and the design of the first Caliste-SO prototype are presented.

  1. Wire number doubling in plasma-shell regime increases z-accelerator x-ray power

    Energy Technology Data Exchange (ETDEWEB)

    Sanford, T.W.L.; Spielman, R.B.; Chandler, G.A. [and others

    1997-11-01

    Doubling the number of tungsten wires from 120 to 240, keeping the mass fixed, increased the radiated x-ray power relative to the electrical power at the insulator stack of the z accelerator by (40{+-}20)% for 8.75- and 20-mm-radii z-pinch wire arrays. Radiation-magneto-hydrodynamic calculations suggest that the arrays were operating in the {open_quotes}plasma shell{close_quotes} regime, where the plasmas generated by the individual wires merge prior to the inward implosion of the entire array.

  2. Solar chameleons

    International Nuclear Information System (INIS)

    Brax, Philippe; Zioutas, Konstantin

    2010-01-01

    We analyze the creation of chameleons deep inside the Sun (R∼0.7R sun ) and their subsequent conversion to photons near the magnetized surface of the Sun. We find that the spectrum of the regenerated photons lies in the soft x-ray region, hence addressing the solar corona problem. Moreover, these back-converted photons originating from chameleons have an intrinsic difference with regenerated photons from axions: their relative polarizations are mutually orthogonal before Compton interacting with the surrounding plasma. Depending on the photon-chameleon coupling and working in the strong coupling regime of the chameleons to matter, we find that the induced photon flux, when regenerated resonantly with the surrounding plasma, coincides with the solar flux within the soft x-ray energy range. Moreover, using the soft x-ray solar flux as a prior, we find that with a strong enough photon-chameleon coupling, the chameleons emitted by the Sun could lead to a regenerated photon flux in the CAST magnetic pipes, which could be within the reach of CAST with upgraded detector performance. Then, axion helioscopes have thus the potential to detect and identify particle candidates for the ubiquitous dark energy in the Universe.

  3. Grazing incidence X-ray fluorescence analysis of buried interfaces in periodically structured crystalline silicon thin-film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Eisenhauer, David; Preidel, Veit; Becker, Christiane [Young Investigator Group Nanostructured Silicon for Photovoltaic and Photonic Implementations (Nano-SIPPE), Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Berlin (Germany); Pollakowski, Beatrix; Beckhoff, Burkhard [Physikalisch-Technische Bundesanstalt, Berlin (Germany); Baumann, Jonas; Kanngiesser, Birgit [Institut fuer Optik und Atomare Physik, Technische Universitaet Berlin (Germany); Amkreutz, Daniel; Rech, Bernd [Institut Silizium Photovoltaik, Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Berlin (Germany); Back, Franziska; Rudigier-Voigt, Eveline [SCHOTT AG, Mainz (Germany)

    2015-03-01

    We present grazing incidence X-ray fluorescence (GIXRF) experiments on 3D periodically textured interfaces of liquid phase crystallized silicon thin-film solar cells on glass. The influence of functional layers (SiO{sub x} or SiO{sub x}/SiC{sub x}) - placed between glass substrate and silicon during crystallization - on the final carbon and oxygen contaminations inside the silicon was analyzed. Baring of the buried structured silicon surface prior to GIXRF measurement was achieved by removal of the original nano-imprinted glass substrate by wet-chemical etching. A broad angle of incidence distribution was determined for the X-ray radiation impinging on this textured surface. Optical simulations were performed in order to estimate the incident radiation intensity on the structured surface profile considering total reflection and attenuation effects. The results indicate a much lower contamination level for SiO{sub x} compared to the SiO{sub x}/SiC{sub x} interlayers, and about 25% increased contamination when comparing structured with planar silicon layers, both correlating with the corresponding solar cell performances. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  4. Extracting ion emission lines from femtosecond-laser plasma x-ray spectra heavily contaminated by spikes

    International Nuclear Information System (INIS)

    Gasilov, S. V.; Faenov, A. Ya.; Pikuz, T. A.; Villoresi, P.; Poletto, L.; Stagira, S.; Calegari, F.; Vozzi, C.; Nisoli, M.

    2007-01-01

    Nowadays charged-coupled device (CCD) detectors are widely used for the registration of multicharged ions x-ray spectra. These spectra are generated in a plasma during interaction of ultrashort, ultraintense laser pulses with solid targets. Strong parasitic radiation from the plasma affects CCD detectors and contaminates resulting spectra, so that spectral features can be completely covered by noise even during measurements with a very short accumulation time. In this work we propose a ''mean to median'' (M2M) algorithm for noise suppression in femtosecond laser plasma x-ray spectra. Series of spectra is necessary for the identification of corrupted data points by the developed method. The algorithm was tested with model spectra which reflect main features of experimental data. In practice we used it for extracting information about spectral lines of Ne-like Fe ions and He-like Al ions which allowed us to calculate plasma parameters. It is demonstrated that M2M method is able to clean spectra with more than 10% of corrupted pixels. Fluctuations in intensity of spectral lines induced by laser instability do not affect validity of the proposed method

  5. X-ray imaging crystal spectroscopy for use in plasma transport research

    Science.gov (United States)

    Reinke, M. L.; Podpaly, Y. A.; Bitter, M.; Hutchinson, I. H.; Rice, J. E.; Delgado-Aparicio, L.; Gao, C.; Greenwald, M.; Hill, K.; Howard, N. T.; Hubbard, A.; Hughes, J. W.; Pablant, N.; White, A. E.; Wolfe, S. M.

    2012-11-01

    This research describes advancements in the spectral analysis and error propagation techniques associated with x-ray imaging crystal spectroscopy (XICS) that have enabled this diagnostic to be used to accurately constrain particle, momentum, and heat transport studies in a tokamak for the first time. Doppler tomography techniques have been extended to include propagation of statistical uncertainty due to photon noise, the effect of non-uniform instrumental broadening as well as flux surface variations in impurity density. These methods have been deployed as a suite of modeling and analysis tools, written in interactive data language (IDL) and designed for general use on tokamaks. Its application to the Alcator C-Mod XICS is discussed, along with novel spectral and spatial calibration techniques. Example ion temperature and radial electric field profiles from recent I-mode plasmas are shown, and the impact of poloidally asymmetric impurity density and natural line broadening is discussed in the context of the planned ITER x-ray crystal spectrometer.

  6. The Spectrometer/Telescope for Imaging X-rays on Solar Orbiter: Flight design, challenges and trade-offs

    International Nuclear Information System (INIS)

    Krucker, S.; Bednarzik, M.; Grimm, O.; Hurford, G.J.; Limousin, O.; Meuris, A.; Orleański, P.; Seweryn, K.; Skup, K.R.

    2016-01-01

    STIX is the X-ray spectral imaging instrument on-board the Solar Orbiter space mission of the European Space Agency, and together with nine other instruments will address questions of the interaction between the Sun and the heliosphere. STIX will study the properties of thermal and accelerated electrons near the Sun through their Bremsstrahlung X-ray emission, addressing in particular the emission from flaring regions on the Sun. The design phase of STIX has been concluded. This paper reports the final flight design of the instrument, focusing on design challenges that were faced recently and how they were addressed.

  7. A study of x-ray emission from the anode region in a plasma focus device

    International Nuclear Information System (INIS)

    Jia Wang; Tsinchi Yang

    1988-01-01

    The physical process of x-ray emission from the anode region in a plasma focus device due to the interaction of a powerful electron beam with the metal anode and with ionised metallic vapour from the anode is investigated. The influence of the magnetic field of the beam is taken into consideration. A MC-PIC model (Monte Carlo-particle in cell) is proposed for the process, in which an electron-photon collision cascade is simulated by the MC approach and the time-dependent state of metallic vapour is determined by PIC computation. The time-resolved energy spectra and angular distributions of x-ray emission from the extending anode region are calculated. The time-integrated characteristics of the x-ray emission can be compared with the results of experiments as far as they are available. (author)

  8. X-ray Emission Line Spectroscopy of Nearby Galaxies

    Science.gov (United States)

    Wang, Daniel

    What are the origins of the diffuse soft X-ray emission from non-AGN galaxies? Preliminary analysis of XMM-Newton RGS spectra shows that a substantial fraction of the emission cannot arise from optically-thin thermal plasma, as commonly assumed, and may originate in charge exchange at the interface with neutral gas. We request the support for a comprehensive observing, data analysis, and modeling program to spectroscopically determine the origins of the emission. First, we will use our scheduled XMM-Newton AO-10 368 ks observations of the nearest compact elliptical galaxy M32 to obtain the first spectroscopic calibration of the cumulative soft X-ray emission from the old stellar population and will develop a spectral model for the charge exchange, as well as analysis tools to measure the spatial and kinematic properties of the X-ray line- emitting plasma. Second, we will characterize the truly diffuse emission from the hot plasma and/or its interplay with the neutral gas in a sample of galactic spheroids and active star forming/starburst regions in nearby galaxies observed by XMM-Newton. In particular, we will map out the spatial distributions of key emission lines and measure (or tightly constrain) the kinematics of hot plasma outflows for a few X-ray-emitting regions with high-quality RGS data. For galaxies with insufficient counting statistics in individual emission lines, we will conduct a spectral stacking analysis to constrain the average properties of the X-ray-emitting plasma. We will use the results of these X-ray spectroscopic analyses, together with complementary X-ray CCD imaging/spectral data and observations in other wavelength bands, to test the models of the emission. In addition to the charge exchange, alternative scenarios such as resonance scattering and relic AGN photo-ionization will also be examined for suitable regions. These studies are important to the understanding of the relationship between the diffuse soft X-ray emission and various

  9. Electroform/Plasma-Spray Laminates for X-Ray Optics

    Science.gov (United States)

    Ulmer, Melville P.; Graham, Michael; Vaynman, Semyon

    2007-01-01

    Electroform/plasma-spray laminates have shown promise as lightweight, strong, low-thermal-expansion components for xray optics. The basic idea is to exploit both (1) the well-established art of fabrication of optical components by replication and (2) plasma spraying as a means of reinforcing a thin replica optic with one or more backing layer(s) having tailorable thermomechanical properties. In x-ray optics as in other applications, replication reduces the time and cost of fabrication because grinding and polishing can be limited to a few thick masters, from which many lightweight replicas can thereafter be made. The first step in the fabrication of a component of the type in question is to make a replica optic by electroforming a thin layer of nickel on a master. Through proper control of the electroforming process conditions, it is possible to minimize residual stress and, hence, to minimize distortion in the replica. Next, a powder comprising ceramic particles coated with a metal compatible with the electroformed nickel is plasma-sprayed onto the backside of the nickel replica. Then through several repetitions and variations of the preceding steps or perhaps a small compressive stress, alternating layers of electroformed nickel and plasma-sprayed metal-coated ceramic powder are deposited. The thicknesses of the layers and the composition of the metal-coated ceramic powder are chosen to optimize the strength, areal mass density, and toughness of the finished component. An important benefit of using both electroforming and plasma spraying is the possibility of balancing stresses to a minimum level, which could be zero or perhaps a small net compressive stress designed to enhance the function of the component in its intended application.

  10. Applications of soft x-ray lasers

    International Nuclear Information System (INIS)

    Skinner, C.H.

    1993-01-01

    The high brightness and short pulse duration of soft x-ray lasers provide unique advantages for novel applications. Imaging of biological specimens using x-ray lasers has been demonstrated by several groups. Other applications to fields such as chemistry, material science, plasma diagnostics, and lithography are beginning to emerge. We review the current status of soft x-ray lasers from the perspective of applications, and present an overview of the applications currently being developed

  11. DUAL-STAGE RECONNECTION DURING SOLAR FLARES OBSERVED IN HARD X-RAY

    International Nuclear Information System (INIS)

    Xu Yan; Jing Ju; Wang Haimin; Cao Wenda

    2010-01-01

    In this Letter, we present hard X-ray (HXR) observation by the Reuven Ramaty High Energy Solar Spectroscopic Imager of the 2003 October 29 X10 flare. Two pairs of HXR conjugate footpoints have been identified during the early impulsive phase. This geometric configuration is very much in the manner predicted by the 'tether-cutting' scenario first proposed by Moore and Roumeliotis. The HXR light curves show that the outer pair of footpoints disappeared much faster than the other pair. This temporal behavior further confirms that this event is a good example of the 'tether-cutting' model. In addition, we reconstructed a three-dimensional magnetic field based on the nonlinear force-free extrapolation and found that each pair of HXR footpoints were indeed linked by corresponding magnetic field lines.

  12. The universe in X-rays

    CERN Document Server

    Hasinger, Günther

    2008-01-01

    In the last 45 years, X-ray astronomy has become an integral part of modern astrophysics and cosmology. There is a wide range of astrophysical objects and phenomena, where X-rays provide crucial diagnostics. In particular they are well suited to study hot plasmas and matter under extreme physical conditions in compact objects. This book summarizes the present status of X-ray astronomy in terms of observational results and their astrophysical interpretation. It is written for students, astrophysicists as well a growing community of physicists interested in the field. An introduction including historical material is followed by chapters on X-ray astronomical instrumentation. The next two parts summarize in 17 chapters the present knowledge on various classes of X-ray sources in the galactic and extragalactic realm. While the X-ray astronomical highlights discussed in this book are mainly based on results from ROSAT, ASCA, RXTE, BeppoSAX, Chandra and XMM-Newton, a final chapter provides an outlook on observation...

  13. Activity-dependent branching ratios in stocks, solar x-ray flux, and the Bak-Tang-Wiesenfeld sandpile model.

    Science.gov (United States)

    Martin, Elliot; Shreim, Amer; Paczuski, Maya

    2010-01-01

    We define an activity-dependent branching ratio that allows comparison of different time series X(t). The branching ratio b(x) is defined as b(x)=E[xi(x)/x]. The random variable xi(x) is the value of the next signal given that the previous one is equal to x, so xi(x)=[X(t+1) | X(t)=x]. If b(x)>1, the process is on average supercritical when the signal is equal to x, while if b(x)efficient market hypothesis." For stock volumes, solar x-ray flux intensities, and the Bak-Tang-Wiesenfeld (BTW) sandpile model, b(x) is supercritical for small values of activity and subcritical for the largest ones, indicating a tendency to return to a typical value. For stock volumes this tendency has an approximate power-law behavior. For solar x-ray flux and the BTW model, there is a broad regime of activity where b(x) approximately equal 1, which we interpret as an indicator of critical behavior. This is true despite different underlying probability distributions for X(t) and for xi(x). For the BTW model the distribution of xi(x) is Gaussian, for x sufficiently larger than 1, and its variance grows linearly with x. Hence, the activity in the BTW model obeys a central limit theorem when sampling over past histories. The broad region of activity where b(x) is close to one disappears once bulk dissipation is introduced in the BTW model-supporting our hypothesis that it is an indicator of criticality.

  14. X-ray pulsars: accretion flow deceleration

    International Nuclear Information System (INIS)

    Miller, G.S.

    1987-01-01

    X-ray pulsars are thought to be neutron stars that derive the energy for their x-ray emission by accreting material onto their magnetic polar caps. The accreting material and the x-ray pulsar atmospheres were idealized as fully ionized plasmas consisting only of electrons and protons. A high magnetic field (∼ 5 x 10 12 Gauss) permeates the atmospheric plasma, and causes the motion of atmospheric electrons perpendicular to the field to be quantized into discrete Landau levels. All atmospheric electrons initially lie in the Landau ground state, but in the author's calculations of Coulomb collisions between atmospheric electrons and accreting protons, he allows for processes that leave the electrons in the first excited Landau level. He also considers interactions between accreting protons and the collective modes of the atmospheric plasma. Division of the electromagnetic interaction of a fast proton with a magnetized plasma into single particle and collective effects is described in detail in Chapter 2. Deceleration of the accretion flow due to Coulomb collisions with atmospheric electrons and collective plasma effects was studied in a number of computer simulations. These simulations, along with a discussion of the physical state of the atmospheric plasma and its interactions with a past proton, are presented in Chapter 3. Details of the atmospheric model and a description of the results of the simulations are given in Chapter 4. Chapter 5 contains some brief concluding remarks, and some thoughts on future research

  15. Study of plasmas created by X-ray laser-matter interaction

    International Nuclear Information System (INIS)

    Galtier, E.

    2010-11-01

    This thesis took advantage of the emerging newly developed 4. generation sources of light, namely the free electron lasers, to create and characterize a state of matter under extreme conditions which is still obscure: the warm dense matter (WDM). WDM is found in giant planets and is also produced in inertial fusion. An experiment allowed to study the transitions between the different phases, solid/WDM/plasma, and characterize the mechanism responsible for the equilibration. The laser pulse FLASH, of duration and energy equal to about 20 femto-seconds and 30 μJ respectively, is micro-focussed on a solid target producing an isochoric heating. The intensity, greater than 10 16 W.cm -2 , has never been reached in such an experimental context so far. Emission spectra from an aluminium plasma are studied with a code coupling a genetic algorithm and a code of atomic physics, in order to interpret the whole temporal evolution of the XUV laser-matter interaction for the first time, despite the time integration of the experimental spectra. The first experimental proof of the important contribution of the Auger effect in the isochoric heating of an aluminium target is established. The first observation of the X-ray emission of a boron nitride target under extreme conditions has been investigated by a preliminary study. Additionally, the effect of hot electrons on the electron population distribution in the energy levels of the ions is analysed and shows an important similarity with the photo-ionization process occurring in XUV/X-ray laser-matter interaction. (author)

  16. Solar--geophysical data number 410, October 1978. Part II. (Comprehensive reports). Data for April 1978--March 1978 and miscellanea

    International Nuclear Information System (INIS)

    Coffey, H.E.

    1978-10-01

    This comprehensive report for April 1978, March 1978 and Miscellaneous data provides data on active regions, synoptic solar maps, solar flares, solar radio waves, energetic solar particles and plasma, synoptic chart, abbreviated calendar record, regional flare index, solar x-ray radiation, cosmic rays, energetic solar particles and plasma for March 1978 and solar flares for February 1978

  17. The 2011 Outburst of Recurrent Nova T Pyx: X-Ray Observations Expose the White Dwarf Mass and Ejection Dynamics

    Science.gov (United States)

    Chomiuk, Laura; Nelson, Thomas; Mukai, Koji; Solokoski, J. L.; Rupen, Michael P.; Page, Kim L.; Osborne, Julian P.; Kuulkers, Erik; Mioduszewski, Amy J.; Roy, Nirupam; hide

    2014-01-01

    The recurrent nova T Pyx underwent its sixth historical outburst in 2011, and became the subject of an intensive multi-wavelength observational campaign.We analyze data from the Swift and Suzaku satellites to produce a detailed X-ray light curve augmented by epochs of spectral information. X-ray observations yield mostly non-detections in the first four months of outburst, but both a super-soft and hard X-ray component rise rapidly after Day 115. The super-soft X-ray component, attributable to the photosphere of the nuclear-burning white dwarf, is relatively cool (approximately 45 electron volts) and implies that the white dwarf in T Pyx is significantly below the Chandrasekhar mass (approximately 1 M). The late turn-on time of the super-soft component yields a large nova ejecta mass (approximately greater than 10(exp -5) solar mass), consistent with estimates at other wavelengths. The hard X-ray component is well fit by a approximately 1 kiloelectron volt thermal plasma, and is attributed to shocks internal to the 2011 nova ejecta. The presence of a strong oxygen line in this thermal plasma on Day 194 requires a significantly super-solar abundance of oxygen and implies that the ejecta are polluted by white dwarf material. The X-ray light curve can be explained by a dual-phase ejection, with a significant delay between the first and second ejection phases, and the second ejection finally released two months after outburst. A delayed ejection is consistent with optical and radio observations of T Pyx, but the physical mechanism producing such a delay remains a mystery.

  18. Caliste-SO, a CdTe based spectrometer for bright solar event observations in hard X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Meuris, A., E-mail: aline.meuris@cea.fr [CEA-Irfu – CEA Saclay, F-91191 Gif-sur-Yvette Cedex (France); Limousin, O.; Gevin, O.; Blondel, C.; Martignac, J. [CEA-Irfu – CEA Saclay, F-91191 Gif-sur-Yvette Cedex (France); Vassal, M.-C.; Soufflet, F.; Fiant, N. [3D Plus – 408 rue Hélène Boucher, F-78532 Buc Cedex (France); Bednarzik, M.; Stutz, S. [Paul Scherrer Institute (PSI), Laboratory for Micro- and Nanotechnology, 5232 Villigen (Switzerland); Grimm, O.; Commichau, V. [ETH Zurich, Institute for Particle Physics, Schafmattstrasse 20, 8093 Zurich (Switzerland)

    2015-07-01

    Caliste-SO is a CdTe hybrid detector designed to be used as a spectrometer for a hard X-ray Fourier telescope. The imaging technique was implemented in the Yohkoh satellite in 1991 and the RHESSI satellite in 2002 to achieve arc-second angular resolution images of solar flares with spectroscopic capabilities. The next generation of such instruments will be the Spectrometer Telescope Imaging X-rays (STIX) on-board the Solar Orbiter mission adopted by the European Space Agency in 2011 for launch in 2017. The design and performance of Caliste-SO allows both high spectral resolution and high count rate measurements from 4 to 150 keV with limited demands on spacecraft resources such as mass, power and volume (critical for interplanetary missions). The paper reports on the flight production of the Caliste-SO devices for STIX, describing the test facilities built-up in Switzerland and France. It illustrates some results obtained with the first production samples that will be mounted in the STIX engineering model.

  19. Activity-dependent branching ratios in stocks, solar x-ray flux, and the Bak-Tang-Wiesenfeld sandpile model

    Science.gov (United States)

    Martin, Elliot; Shreim, Amer; Paczuski, Maya

    2010-01-01

    We define an activity-dependent branching ratio that allows comparison of different time series Xt . The branching ratio bx is defined as bx=E[ξx/x] . The random variable ξx is the value of the next signal given that the previous one is equal to x , so ξx={Xt+1∣Xt=x} . If bx>1 , the process is on average supercritical when the signal is equal to x , while if bxmarket hypothesis.” For stock volumes, solar x-ray flux intensities, and the Bak-Tang-Wiesenfeld (BTW) sandpile model, bx is supercritical for small values of activity and subcritical for the largest ones, indicating a tendency to return to a typical value. For stock volumes this tendency has an approximate power-law behavior. For solar x-ray flux and the BTW model, there is a broad regime of activity where bx≃1 , which we interpret as an indicator of critical behavior. This is true despite different underlying probability distributions for Xt and for ξx . For the BTW model the distribution of ξx is Gaussian, for x sufficiently larger than 1, and its variance grows linearly with x . Hence, the activity in the BTW model obeys a central limit theorem when sampling over past histories. The broad region of activity where bx is close to one disappears once bulk dissipation is introduced in the BTW model—supporting our hypothesis that it is an indicator of criticality.

  20. An experimental measurement of metal multilayer x-ray reflectivity degradation due to intense x-ray flux

    International Nuclear Information System (INIS)

    Hockaday, M.Y.P.

    1987-06-01

    The degradation of the x-ray reflection characteristics of metal multilayer Bragg diffractors due to intense x-ray flux was investigated. The Z-pinch plasma produced by PROTO II of Sandia National Laboratories, Albuquerque, New Mexico, was used as the source. The plasma generated total x-ray yields of as much as 40 kJ with up to 15 kJ in the neon hydrogen- and helium-like resonance lines in nominal 20-ns pulses. Molybdenum-carbon, palladium-carbon, and tungsten-carbon metal multilayers were placed at 15 and 150 cm from the plasma center. The multilayers were at nominal angles of 5 0 and 10 0 to diffract the neon resonance lines. The time-integrated x-ray reflection of the metal multilayers was monitored by x-ray film. A fluorescer-fiber optic-visible streak camera detector system was then used to monitor the time-resolved x-ray reflection characteristics of 135 A- 2d tungsten-carbon multilayers. A large specular component in the reflectivity prevented determination of the rocking curve of the multilayer. For a neon implosion onto a vanadium-doped polyacrylic acid foam target shot, detailed modeling was attempted. The spectral flux was determined with data from 5 XRD channels and deconvolved using the code SHAZAM. The observed decay in reflectivity was assumed to correspond to the melting of the first tungsten layer. A ''conduction factor'' of 82 was required to manipulate the heat loading of the first tungsten layer such that the time of melting corresponded to the observed decay. The power at destruction was 141 MW/cm 2 and the integrated energy at destruction was 2.0 J/cm 2 . 82 refs., 66 figs., 10 tabs

  1. The cluster charge identification in the GEM detector for fusion plasma imaging by soft X-ray diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Czarski, T., E-mail: tomasz.czarski@ifpilm.pl; Chernyshova, M.; Malinowski, K. [Institute of Plasma Physics and Laser Microfusion, Hery 23, 01-497 Warsaw (Poland); Pozniak, K. T.; Kasprowicz, G.; Kolasinski, P.; Krawczyk, R.; Wojenski, A.; Zabolotny, W. [Warsaw University of Technology, Nowowiejska 15/19, 00-665 Warsaw (Poland)

    2016-11-15

    The measurement system based on gas electron multiplier detector is developed for soft X-ray diagnostics of tokamak plasmas. The multi-channel setup is designed for estimation of the energy and the position distribution of an X-ray source. The focal measuring issue is the charge cluster identification by its value and position estimation. The fast and accurate mode of the serial data acquisition is applied for the dynamic plasma diagnostics. The charge clusters are counted in the space determined by 2D position, charge value, and time intervals. Radiation source characteristics are presented by histograms for a selected range of position, time intervals, and cluster charge values corresponding to the energy spectra.

  2. SECCOX, a novel x-ray characterization bench for Bragg crystals and x-rays optics

    International Nuclear Information System (INIS)

    Caillaud, T.; Manson, M.; Desenne, D.; Goze, B.; Rivet, A.; Derouineau, Ph.

    2007-01-01

    Laser programs require the use of a large number of calibrated x-ray crystals implemented inside spectrometers and microscopes used in diagnostics. In this context, a new apparatus was designed in collaboration with CELIA laboratory, Saint-Gobain Crystals and Detectors and CEA to characterize x-ray Bragg crystals. Station d'Etude et de Caracterisation des Cristaux pour les Optiques X (SECCOX) is based on a micrometric x-ray source and an automated spectrometer equipped with a CCD camera. Properties such as homogeneity, resolution, radius of curvature and reflectivity are measured to guarantee diagnostic performance in laser-plasma physics experiments. We will present the experimental device, techniques and results of the calibration obtained. (authors)

  3. The analysis and the three-dimensional, forward-fit modeling of the X-ray and the microwave emissions of major solar flares

    Science.gov (United States)

    Kuroda, Natsuha; Wang, Haimin; Gary, Dale E.

    2017-08-01

    It is well known that the time profiles of the hard X-ray (HXR) emission and the microwave (MW) emission during the impulsive phase of the solar flare are well correlated, and that their analysis can lead to the understandings of the flare-accelerated electrons. In this work, we first studied the source locations of seven distinct temporal peaks observed in HXR and MW lightcurves of the 2011-02-15 X2.2 flare using the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and Nobeyama Radioheliograph. We found that the seven emission peaks did not come from seven spatially distinct sites in HXR and MW, but rather in HXR we observed a sudden change in location only between the second and the third peak, with the same pattern occurring, but evolving more slowly in MW, which is consistent with the tether-cutting model of solar flares. Next, we closely examine the widely-used notion of a "common population" of the accelerated electrons producing the HXR and the MW, which has been challenged by some studies suggesting the differences in the inferred energy spectral index and emitting energies of the HXR- and MW- producing electrons. We use the Non-linear Force Free Field model extrapolated from the observed photospheric magnetogram in the three-dimensional, multi-wavelength modeling platform GX Simulator, and attempt to create a unified electron population model that can simultaneously reproduce the observed X-ray and MW observations of the 2015-06-22 M6.5 flare. We constrain the model parameters by the observations made by the highest-resolving instruments currently available in two wavelengths, the RHESSI for X-ray and the Expanded Owens Valley Solar Array for MW. The results suggest that the X-ray emitting electron population model fits to the standard flare model with the broken, hardening power-law spectrum at ~300 keV that simultaneously produces the HXR footpoint emission and the MW high frequency emission, and also reveals that there could be a “X-ray

  4. Microscopic nonlinear relativistic quantum theory of absorption of powerful x-ray radiation in plasma.

    Science.gov (United States)

    Avetissian, H K; Ghazaryan, A G; Matevosyan, H H; Mkrtchian, G F

    2015-10-01

    The microscopic quantum theory of plasma nonlinear interaction with the coherent shortwave electromagnetic radiation of arbitrary intensity is developed. The Liouville-von Neumann equation for the density matrix is solved analytically considering a wave field exactly and a scattering potential of plasma ions as a perturbation. With the help of this solution we calculate the nonlinear inverse-bremsstrahlung absorption rate for a grand canonical ensemble of electrons. The latter is studied in Maxwellian, as well as in degenerate quantum plasma for x-ray lasers at superhigh intensities and it is shown that one can achieve the efficient absorption coefficient in these cases.

  5. DNA strand breaks induced by soft X-ray pulses from a compact laser plasma source

    Science.gov (United States)

    Adjei, Daniel; Wiechec, Anna; Wachulak, Przemyslaw; Ayele, Mesfin Getachew; Lekki, Janusz; Kwiatek, Wojciech M.; Bartnik, Andrzej; Davídková, Marie; Vyšín, Luděk; Juha, Libor; Pina, Ladislav; Fiedorowicz, Henryk

    2016-03-01

    Application of a compact laser plasma source of soft X-rays in radiobiology studies is demonstrated. The source is based on a laser produced plasma as a result of irradiation of a double-stream gas puff target with nanosecond laser pulses from a commercially available Nd:YAG laser. The source allows irradiation of samples with soft X-ray pulses in the "water window" spectral range (wavelength: 2.3-4.4 nm; photon energy: 280-560 eV) in vacuum or a helium atmosphere at very high-dose rates and doses exceeding the kGy level. Single-strand breaks (SSB) and double-strand breaks (DBS) induced in DNA plasmids pBR322 and pUC19 have been measured. The different conformations of the plasmid DNA were separated by agarose gel electrophoresis. An exponential decrease in the supercoiled form with an increase in linear and relaxed forms of the plasmids has been observed as a function of increasing photon fluence. Significant difference between SSB and DSB in case of wet and dry samples was observed that is connected with the production of free radicals in the wet sample by soft X-ray photons and subsequent affecting the plasmid DNA. Therefore, the new source was validated to be useful for radiobiology experiments.

  6. X-ray emission from a high-atomic-number z-pinch plasma created from compact wire arrays

    International Nuclear Information System (INIS)

    Sanford, T.W.L.; Nash, T.J.; Marder, B.M.

    1996-03-01

    Thermal and nonthermal x-ray emission from the implosion of compact tungsten wire arrays, driven by 5 MA from the Saturn accelerator, are measured and compared with LLNL Radiation-Hydro-Code (RHC) and SNL Hydro-Code (HC) numerical models. Multiple implosions, due to sequential compressions and expansions of the plasma, are inferred from the measured multiple x-radiation bursts. Timing of the multiple implosions and the thermal x-ray spectra measured between 1 and 10 keV are consistent with the RHC simulations. The magnitude of the nonthermal x-ray emission measured from 10 to 100 keV ranges from 0.02 to 0.08% of the total energy radiated and is correlated with bright-spot emission along the z-axis, as observed in earlier Gamble-11 single exploding-wire experiments. The similarities of the measured nonthermal spectrum and bright-spot emission with those measured at 0.8 MA on Gamble-II suggest a common production mechanism for this process. A model of electron acceleration across magnetic fields in highly-collisional, high-atomic-number plasmas is developed, which shows the existence of a critical electric field, E c , below which strong nonthermal electron creation (and the associated nonthermal x rays) do not occur. HC simulations show that significant nonthermal electrons are not expected in this experiment (as observed) because the calculated electric fields are at least one to two orders-of-magnitude below E c . These negative nonthermal results are confirmed by RHC simulations using a nonthermal model based on a Fokker-Plank analysis. Lastly, the lower production efficiency and the larger, more irregular pinch spots formed in this experiment relative to those measured on Gamble II suggest that implosion geometries are not as efficient as single exploding-wire geometries for warm x-ray production

  7. Development of multilayer optics for X-ray broadband spectrometry of plasma emission

    International Nuclear Information System (INIS)

    Emprin, Benoit

    2014-01-01

    Within the framework of the research on inertial confinement fusion, the 'Commissariat a l'energie atomique et aux energies alternatives' has studied and implemented an absolute calibrated time-Resolved broadband soft x-Ray spectrometer, called 'Diagnostic de Mesure du rayonnement X'. This diagnostic, composed of 20 measurement channels, measures the emitted radiant power from a laser created plasma in the range from 50 eV to 20 keV. We have developed additional measurement channels to obtain redundancy and an improvement in measurement accuracy. The principle of these new channels is based on an original concept to obtain spectral bounded flat-Responses. Two channels have been developed for the 2 - 4 keV and 4 - 6 keV spectral ranges, using aperiodic multilayer mirrors made at the 'Laboratoire Charles Fabry' with Cr/Sc and Ni/W/SiC/W layers respectively. These mirrors were characterized at synchrotron radiation facilities and integrated into the spectrometer. The two new channels were used during laser-Plasma experimental campaigns at the OMEGA laser facility in Rochester (USA). This allowed us to determine directly the radiant power with only one measurement within a certain spectral band, and with a better precision when compared with using standard channels. The results, in good agreement with the standard measurement channels, allowed us to validate the use of aperiodic multilayer mirrors for X-Ray broadband spectrometry. (author) [fr

  8. Determination of wafer bonding mechanisms for plasma activated SiN films with x-ray reflectivity

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, S [Department of Materials Science and Engineering, University of California, Los Angeles, CA 90095 (United States); Sandhu, R [Department of Materials Science and Engineering, University of California, Los Angeles, CA 90095 (United States); Wojtowicz, M [Northrop Grumman Space Technology, Redondo Beach, CA 90278 (United States); Sun, Y [Department of Chemical Engineering, University of California, Los Angeles, CA 90095 (United States); Hicks, R [Department of Chemical Engineering, University of California, Los Angeles, CA 90095 (United States); Goorsky, M S [Department of Materials Science and Engineering, University of California, Los Angeles, CA 90095 (United States)

    2005-05-21

    Specular and diffuse x-ray reflectivity measurements were employed for wafer bonding studies of surface and interfacial reactions in {approx}800 A thick SiN films deposited on III-V substrates. CuK{sub {alpha}}{sub 1} radiation was employed for these measurements. The as-deposited films show very low surface roughness and uniform, high density SiN. Reflectivity measurements show that an oxygen plasma treatment converts the nitride surface to a somewhat porous SiO{sub x} layer (67 A thick, at 80% of SiO{sub 2} density), with confirmation of the oxide formation from x-ray photoelectron spectroscopy. Reactions at the bonded interface of two oxygen plasma treated SiN layers were examined using a bonded structure from which one of the III-V wafers is removed. Reflectivity measurements of bonded structures annealed at 150 deg. C and 300 deg. C show an increase in the SiO{sub x} layer density and thickness and even a density gradient across this interface. The increase in density is correlated with an increase in bond strength, where after the 300 deg. C anneal, a high interfacial bond strength, exceeding the bulk strength, was achieved.

  9. Coaxial gun parameters and X-ray emission

    International Nuclear Information System (INIS)

    Soliman, H.M.; El-Aragi, G.M.; Saudy, A.H.; Masoud, M.M.

    1994-01-01

    The paper presents the results of investigation with 3 kJ coaxial plasma gun, which operated with argon gas at pressure 0.8 torr. The coaxial plasma gun parameters are investigated by pick up coils, double electric probe, and x-ray probe. The mean electron temperature and density of the ejected plasma are 25 eV and 10 15 cm -3 respectively. The maximum kinetic pressure of the ejected plasma in the expansion chamber appears after 10 μs from the start of the discharge current. The energetic electrons is detected by an x-ray probe which showed a single pulse of electrons with energy ≅ 3 Kev. (orig.)

  10. Application of Laser Plasma Sources of Soft X-rays and Extreme Ultraviolet (EUV) in Imaging, Processing Materials and Photoionization Studies

    Science.gov (United States)

    Fiedorowicz, H.; Bartnik, A.; Wachulak, P. W.; Jarocki, R.; Kostecki, J.; Szczurek, M.; Ahad, I. U.; Fok, T.; Szczurek, A.; Wȩgrzyński, Ł.

    In the paper we present new applications of laser plasma sources of soft X-rays and extreme ultraviolet (EUV) in various areas of plasma physics, nanotechnology and biomedical engineering. The sources are based on a gas puff target irradiated with nanosecond laser pulses from commercial Nd: YAG lasers, generating pulses with time duration from 1 to 10 ns and energies from 0.5 to 10 J at a 10 Hz repetition rate. The targets are produced with the use of a double valve system equipped with a special nozzle to form a double-stream gas puff target which allows for high conversion efficiency of laser energy into soft X-rays and EUV without degradation of the nozzle. The sources are equipped with various optical systems to collect soft X-ray and EUV radiation and form the radiation beam. New applications of these sources in imaging, including EUV tomography and soft X-ray microscopy, processing of materials and photoionization studies are presented.

  11. X-Ray, EUV, UV and Optical Emissivities of Astrophysical Plasmas

    Science.gov (United States)

    Raymond, John C.; West, Donald (Technical Monitor)

    2000-01-01

    This grant primarily covered the development of the thermal X-ray emission model code called APEC, which is meant to replace the Raymond and Smith (1977) code. The new code contains far more spectral lines and a great deal of updated atomic data. The code is now available (http://hea-www.harvard.edu/APEC), though new atomic data is still being added, particularly at longer wavelengths. While initial development of the code was funded by this grant, current work is carried on by N. Brickhouse, R. Smith and D. Liedahl under separate funding. Over the last five years, the grant has provided salary support for N. Brickhouse, R. Smith, a summer student (L. McAllister), an SAO predoctoral fellow (A. Vasquez), and visits by T. Kallman, D. Liedahl, P. Ghavamian, J.M. Laming, J. Li, P. Okeke, and M. Martos. In addition to the code development, the grant supported investigations into X-ray and UV spectral diagnostics as applied to shock waves in the ISM, accreting black holes and white dwarfs, and stellar coronae. Many of these efforts are continuing. Closely related work on the shock waves and coronal mass ejections in the solar corona has grown out of the efforts supported by the grant.

  12. Spectroscopic analysis of sodium-bearing Z-pinch plasmas for their x-ray-laser pumping efficiency

    International Nuclear Information System (INIS)

    Apruzese, J.P.; Mehlman, G.; Davis, J.; Rogerson, J.E.; Scherrer, V.E.; Stephanakis, S.J.; Ottinger, P.F.; Young, F.C.

    1987-01-01

    Using axially resolved spectra, we have derived temperature and density profiles of sodium-bearing Z-pinch plasmas produced on the Naval Research Laboratory's Gamble-II generator. The variations in the output power of the Na X 1s 2 1 S 0 --1s2p 1 P 1 line which can be used to pump a Ne IX x-ray laser, are analyzed as functions of mass loading, temperature, and density. The fractional conversion of plasma energy to lasing lines is projected as 10/sup -3/ if an optimum neon lasant plasma can be prepared and pumped to saturation. This would require an increase in load current of less than or equal to 50% from the present 1.2 MA

  13. Estimation of electron temperature of micropinch discharge plasma according to attenuation of X-ray flux in photoemulsion

    International Nuclear Information System (INIS)

    Averin, M.S.; Bajkov, A.Yu.; Bashutin, O.A.; Vovchenko, E.D.; Dmitrusenko, A.S.; Savelov, A.S.; Li San-wei

    2006-01-01

    The X-ray flux generated by the micropinch discharge on the heavy-current pulsed micropinch device Zona-2 is investigated. The study of the spatial structure and the spectral composition of X radiation of the micropinch plasma is carried out by means of the experimental installation which consists of the three-channel camera-obscure, the set of absorbing filters (Ti-Fe, Fe-Cu, Zn-Se filters) , two focusing spherical spectrographs and the plastic scintillation detector NE111. The spatial distribution of the electron temperature is determined on plasma images in X-rays behind different filters. The form of attenuation curves gives the evidence of the presence of two groups of electrons with different energies in the micropinch range: the thermal electron temperature ∼ 1.9 ± 0.7 keV and the epithermal electron temperature ∼ 20 ± 8 keV [ru

  14. Investigation of Relationship between High-energy X-Ray Sources and Photospheric and Helioseismic Impacts of X1.8 Solar Flare of 2012 October 23

    Energy Technology Data Exchange (ETDEWEB)

    Sharykin, I. N.; Zimovets, I. V. [Space Research Institute (IKI) of the Russian Academy of Sciences, Moscow (Russian Federation); Kosovichev, A. G.; Sadykov, V. M. [New Jersey Institute of Technology, Newark, NJ (United States); Myshyakov, I. I., E-mail: ivan.sharykin@phystech.edu [Institute of Solar-Terrestrial Research (ISTP) of the Russian Academy of Sciences, Siberian Branch, Irkutsk (Russian Federation)

    2017-07-01

    The X-class solar flare of 2012 October 23 generated continuum photospheric emission and a strong helioseismic wave (“sunquake”) that points to an intensive energy release in the dense part of the solar atmosphere. We study properties of the energy release with high temporal and spatial resolutions, using photospheric data from the Helioseismic Magnetic Imager (HMI) on board Solar Dynamics Observatory , and hard X-ray observations made by RHESSI . For this analysis we use level-1 HMI data (filtergrams), obtained by scanning the Fe i line (6731 Å) with the time cadence of ∼3.6 s and spatial resolution of ∼0.″5 per pixel. It is found that the photospheric disturbances caused by the flare spatially coincide with the region of hard X-ray emission but are delayed by ≲4 s. This delay is consistent with predictions of the flare hydrodynamics RADYN models. However, the models fail to explain the magnitude of variations observed by the HMI. The data indicate that the photospheric impact and helioseismic wave might be caused by the electron energy flux, which is substantially higher than that in the current flare radiative hydrodynamic models.

  15. Picosecond chronography at x-ray wavelengths

    International Nuclear Information System (INIS)

    Bird, P.R.; Bradley, D.J.; Roddie, A.G.; Sibbett, W.; Key, M.H.; Lamb, M.J.; Lewis, C.L.S.

    1975-01-01

    An ultrafast streak camera for vacuum U-V to X-ray radiation is described. Preliminary measurements on laser-produced plasmas are presented with time resolution down to 150 psecs and space resolution down to 40μm for 1keV X-ray emission from a plasma generated by 2GW laser pulses focussed on a Cu target. High sensitivity and wide spectral bandwidth is due to front surface photoemission at oblique incidence. Time resolution capability of 40 psec and simultaneous spatial resolution down to a few microns is theoretically possible with this system. (author)

  16. Discrimination and quantification of contamination and implanted solar wind in Genesis collector shards using grazing incidence synchrotron x-ray techniques: Initial results

    International Nuclear Information System (INIS)

    Kitts, K.; Sutton, S.; Eng, P.; Ghose, S.; Burnett, D.

    2006-01-01

    Grazing incidence X-ray fluorescence is a non-destructive technique that can differentiate the embedded solar wind component from surface contamination and collector background in the Genesis shards. Initial solar Fe abundance in D30554 is 8 x 10 12 /cm 2 . Accurate knowledge of the composition of the Sun provides a baseline, which allows an understanding of how the solar system has evolved over time and how solar processes and solar wind mechanics behave. Unfortunately, the errors in photospheric abundances are too large for many planetary science problems and this hampers our understanding of these different processes. Analyses of solar wind implanted in meteorites or lunar soils have provided more precise data but alteration processes on these bodies may complicate such information. In response to this need for pristine solar wind samples, NASA developed and launched the Genesis Probe. Unfortunately, the probe smashed into the Utah desert shattering the 300 collector plates into 15,000+ pieces all of which are now coated in a both a fine terrestrial dust and Si and Ge powder from the disrupted collectors themselves. The solar wind penetration depth is 100-200 nm and the superposed contamination layers are typically 40-50 nm. Stringent cleaning regimes have the potential of removing the solar wind itself. The best solution is to have sufficient spatial resolution to separately analyze the surface contamination and penetrated solar wind. To that end, three Genesis collector array shards and their appropriate flight spares were characterized via grazing incidence x-ray fluorescence and x-ray reflectivity. The goals were (1) to evaluate the various cleaning methods used to eliminate contamination, (2) to identify the collector substrates most suited for this technique, (3) to determine whether the solar wind signature could be deconvolved from the collector background signature, and (4) to measure the relative abundances of Ca to Ge in the embedded solar wind.

  17. Spectral and temporal properties of the X-ray pulsar SMC X-1 at hard X-rays

    Science.gov (United States)

    Kunz, M.; Gruber, D. E.; Kendziorra, E .; Kretschmar, P.; Maisack, M.; Mony, B.; Staubert, R.; Doebereiner, S.; Englhauser, J.; Pietsch, W.

    1993-01-01

    The binary X-ray pulsar SMC X- 1 has been observed at hard X-rays with the High Energy X-Ray Experiment (HEXE) on nine occasions between Nov. 1987 and March 1989. A thin thermal bremsstrahlung fit to the phase averaged spectrum yields a plasma temperature (14.4 +/- 1.3) keV and a luminosity above (1.1 +/- 0.1) x 10 exp 38 erg/s in the 20-80 keV band. Pulse period values have been established for three observations, confirming the remarkably stable spin-up trend of SMC X-1. In one of the three observations the pulse profile was seen to deviate from a dominant double pulsation, while at the same time the pulsed fraction was unusually large. For one observation we determined for the first time the pulsed fraction in narrow energy bands. It increases with photon energy from about 20 percent up to over 60 percent in the energy range from 20 to 80 keV.

  18. Research on pinches driven by Speed-2 generator: Hard X-ray and neutron emission in plasma focus configuration

    Energy Technology Data Exchange (ETDEWEB)

    Soto, L.; Moreno, J.; Silva, P.; Sylvester, G.; Zambra, M.; Pavez, C. [Comision Chilena de Energia Nuclear, Santiago (Chile); Pavez, C. [Universidad de Concepcion (Chile); Raspa, V. [Buenos Aires Univ., PLADEMA, CONICET and INFIP (Argentina); Castillo, F. [Insitituto de Ciencias Nucleares, UNAM (Mexico); Kies, W. [Heinrich-Heine-Univ., Dusseldorf (Germany)

    2004-07-01

    Speed-2 is a generator based on Marx technology and was designed in the University of Dusseldorf. Speed-2 consists on 40 +/- Marx modules connected in parallel (4.1 {mu}F equivalent Marx generator capacity, 300 kV, 4 MA in short circuit, 187 kJ, 400 ns rise time, dI/dt {approx} 10{sup 13} A/s). Currently Speed-2 is operating at CCHEN (Chilean nuclear energy commission), being the most powerful and energetic device for dense transient plasma in the Southern Hemisphere. Most of the previous works developed in Speed-2 at Dusseldorf were done in a plasma focus configuration for soft X-ray emission and the neutron emission from Speed-2 was not completely studied. The research program at CCHEN considers experiments in different pinch configurations (plasma focus, gas puffed plasma focus, gas embedded Z-pinch, wire arrays) at current of hundred of kilo- to mega-amperes, using the Speed-2 generator. The Chilean operation has begun implementing and developing diagnostics in a conventional plasma focus configuration operating in deuterium in order to characterize the neutron emission and the hard X-ray production. Silver activation counters, plastics CR39 and scintillator-photomultiplier detectors are used to characterize the neutron emission. Images of metallic plates with different thickness are obtained on commercial radiographic film, Agfa Curix ST-G2, in order to characterize an effective energy of the hard X-ray outside of the discharge. (authors)

  19. Studies of soft x-ray emission during solar flares

    International Nuclear Information System (INIS)

    Anandaram, M.N.

    1973-01-01

    Solar flare soft x-ray emission from 0.5 A to 8.5 A was observed during 1967-68 by Bragg crystal (LiF and EDDT) spectrometers aboard the OSO-4 satellite and also by NRL broad-band ionization detectors aboard the OGO-4 satellite. In this work, instrumental parameters for the LiF crystal spectrometer based on experimental values have been determined and used in the data analysis. The total continuum emission in the 0.5 to 3 A and the 1 to 8 A broad band segments has been determined from OGO-4 data for 21 flares. In doing this, a simple and approximate method of converting the total emission based on the gray body approximation (in which the OGO-4 data are reported) to one based on the thermal continuum spectrum has been developed. (author)

  20. Simulation of enhanced characteristic x rays from a 40-MeV electron beam laser accelerated in plasma

    Directory of Open Access Journals (Sweden)

    L. Nikzad

    2012-02-01

    Full Text Available Simulation of x-ray generation from bombardment of various solid targets by quasimonoenergetic electrons is considered. The electron bunches are accelerated in a plasma produced by interaction of 500 mJ, 30 femtosecond laser pulses with a helium gas jet. These relativistic electrons propagate in the ion channel generated in the wake of the laser pulse. A beam of MeV electrons can interact with targets to generate x-ray radiation with keV energy. The MCNP-4C code based on Monte Carlo simulation is employed to compare the production of bremsstrahlung and characteristic x rays between 10 and 100 keV by using two quasi-Maxwellian and quasimonoenergetic energy distributions of electrons. For a specific electron spectrum and a definite sample, the maximum x-ray flux varies with the target thickness. Besides, by increasing the target atomic number, the maximum x-ray flux is increased and shifted towards a higher energy level. It is shown that by using the quasimonoenergetic electron profile, a more intense x ray can be produced relative to the quasi-Maxwellian profile (with the same total energy, representing up to 77% flux enhancement at K_{α} energy.

  1. X-Ray photoelectron spectroscopy analysis of plasma-polymer interactions for development of low-damage plasma processing of soft materials

    International Nuclear Information System (INIS)

    Setsuhara, Yuichi; Cho, Ken; Shiratani, Masaharu; Sekine, Makoto; Hori, Masaru

    2010-01-01

    Plasma-polymer interactions have been investigated using atomic force microscopy (AFM) and x-ray photoelectron spectroscopy (XPS) of polyethyleneterephthalate (PET) films, which have been exposed to argon plasmas driven by low-inductance antenna modules as a parameter of ion energy. The AFM images indicated that the argon plasma exposure exhibited a significant change in surface roughness. The XPS analyses suggested that the degradation of chemical bonding structure and/or bond scission of PET could be effectively suppressed in the plasma exposures with ion energies below 6 eV. However, significant degradations of O = C-O bond, C-O bond and phenyl group were observed with increasing ion energy above 6 eV.

  2. Particle-in-cell simulations of multi-MeV pulsed X-ray induced air plasmas at low pressures

    International Nuclear Information System (INIS)

    Ribière, M.; D'Almeida, T.; Gaufridy de Dortan, F. de; Maulois, M.; Delbos, C.; Garrigues, A.; Cessenat, O.; Azaïs, B.

    2016-01-01

    A full kinetic modelling of the charge particles dynamics generated upon the irradiation of an air-filled cavity by a multi-MeV pulsed x-ray is performed. From the calculated radiative source generated by the ASTERIX generator, we calculated the electromagnetic fields generated by x-ray induced air plasmas in a metallic cavity at different pressures. Simulations are carried out based on a Particle-In-Cell interpolation method which uses 3D Maxwell-Vlasov calculations of the constitutive charged species densities of air plasmas at different pressures at equilibrium. The resulting electromagnetic fields within the cavity are calculated for different electron densities up to 4 × 10"1"0" cm"−"3. For each air pressure, we show electronic plasma waves formation followed by Landau damping. As electron density increases, the calculations exhibit space-charged neutralization and return current formation.

  3. Proposal for electron beam induced remote sensing x-ray fluorescence investigation of minor bodies in the solar system

    International Nuclear Information System (INIS)

    Hrehuss, G.; Gombosi, T.I.; Naday, I.; Pogany, L.; Szegoe, K.

    1983-11-01

    The composition of the surface material of minor bodies in the solar system can be measured using a semiconductor soft x-ray spectrometer mounted on the space probe. The characteristic x-rays are excited by a 20 kV low current electron beam of a space-born electron gun. After the description of the main features of the technique, estimations on its sensitivity, supported by a model experiment, are given. The minimum fly-by distance to apply this method can be estimated as a few kilometers. (author)

  4. Accelerated gradient methods for the x-ray imaging of solar flares

    Science.gov (United States)

    Bonettini, S.; Prato, M.

    2014-05-01

    In this paper we present new optimization strategies for the reconstruction of x-ray images of solar flares by means of the data collected by the Reuven Ramaty high energy solar spectroscopic imager. The imaging concept of the satellite is based on rotating modulation collimator instruments, which allow the use of both Fourier imaging approaches and reconstruction techniques based on the straightforward inversion of the modulated count profiles. Although in the last decade, greater attention has been devoted to the former strategies due to their very limited computational cost, here we consider the latter model and investigate the effectiveness of different accelerated gradient methods for the solution of the corresponding constrained minimization problem. Moreover, regularization is introduced through either an early stopping of the iterative procedure, or a Tikhonov term added to the discrepancy function by means of a discrepancy principle accounting for the Poisson nature of the noise affecting the data.

  5. kHz femtosecond laser-plasma hard X-ray and fast ion source

    International Nuclear Information System (INIS)

    Thoss, A.; Korn, G.; Stiel, H.; Voigt, U.; Elsaesser, T.; Richardson, M.C.; Siders, C.W.; Faubel, M.

    2002-01-01

    We describe the first demonstration of a new stable, kHz femtosecond laser-plasma source of hard x-ray continuum and K α emission using a thin liquid metallic jet target. kHz femtosecond x-ray sources will find many applications in time-resolved x-ray diffraction and microscopy studies. As high intensity lasers become more compact and operate at increasingly high repetition-rates, they require a target configuration that is both repeatable from shot-to-shot and is debris-free. We have solved this requirement with the use of a fine (10-30 μm diameter) liquid metal jet target that provides a pristine, unperturbed filament surface at rates >100 kHz. A number of liquid metal targets are considered. We will show hard x-ray spectra recorded from liquid Ga targets that show the generation of the 9.3 keV and 10.3 keV, K α and K β lines superimposed on a multi-keV Bremsstrahlung continuum. This source was generated by a 50fs duration, 1 kHz, 2W, high intensity Ti:Sapphire laser. We will discuss the extension of this source to higher powers and higher repetition rates, providing harder x-ray emission, with the incorporation of pulse-shaping and other techniques to enhance the x-ray conversion efficiency. Using the same liquid target technology, we have also demonstrated the generation of forward-going sub-MeV protons from a 10 μm liquid water target at 1 kHz repetition rates. kHz sources of high energy ions will find many applications in time-resolved particle interaction studies, as well as lead to the efficient generation of short-lived isotopes for use in nuclear medicine and other applications. The protons were detected with CR-39 track detectors both in the forward and backward directions up to energies of ∼500 keV. As the intensity of compact high repetition-rate lasers sources increase, we can expect improvements in the energy, conversion efficiency and directionality to occur. The impact of these developments on a number of fields will be discussed. As compact

  6. SYMBIOTIC STARS IN X-RAYS. III. SUZAKU OBSERVATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Nuñez, N. E. [Instituto de Ciencias Astronómicas de la Tierra y del Espacio (ICATE-UNSJ, CONICET), Av. España (S) 1512, J5402DSP, San Juan (Argentina); Nelson, T. [Minnesota Institute for Astrophysics, University of Minnesota, Minneapolis, MN, 55455 (United States); Mukai, K. [CRESST and X-ray Astrophysics Laboratory, (NASA/GSFC), Greenbelt, MD 20 771, USA. (United States); Sokoloski, J. L. [Columbia Astrophysics Lab, 550 W120th St., 1027 Pupin Hall, MC 5247 Columbia University, 10027, New York (United States); Luna, G. J. M., E-mail: nnunez@icate-conicet.gov.ar [Instituto de Astronomía y Física del Espacio (IAFE, CONICET-UBA), Av. Inte. Güiraldes 2620, C1428ZAA, Buenos Aires (Argentina)

    2016-06-10

    We describe the X-ray emission as observed by Suzaku from five symbiotic stars that we selected for deep Suzaku observations after their initial detection with ROSAT, ASCA , and Swift . We find that the X-ray spectra of all five sources can be adequately fit with absorbed optically thin thermal plasma models, with either single- or multi-temperature plasmas. These models are compatible with the X-ray emission originating in the boundary layer between an accretion disk and a white dwarf. The high plasma temperatures of kT > 3 keV for all five targets were greater than expected for colliding winds. Based on these high temperatures as well as previous measurements of UV variability and UV luminosity and the large amplitude of X-ray flickering in 4 Dra, we conclude that all five sources are accretion-powered through predominantly optically thick boundary layers. Our X-ray data allow us to observe a small optically thin portion of the emission from these boundary layers. Given the time between previous observations and these observations, we find that the intrinsic X-ray flux and the intervening absorbing column can vary by factors of three or more on a timescale of years. However, the location of the absorber and the relationship between changes in accretion rate and absorption are still elusive.

  7. SYMBIOTIC STARS IN X-RAYS. III. SUZAKU OBSERVATIONS

    International Nuclear Information System (INIS)

    Nuñez, N. E.; Nelson, T.; Mukai, K.; Sokoloski, J. L.; Luna, G. J. M.

    2016-01-01

    We describe the X-ray emission as observed by Suzaku from five symbiotic stars that we selected for deep Suzaku observations after their initial detection with ROSAT, ASCA , and Swift . We find that the X-ray spectra of all five sources can be adequately fit with absorbed optically thin thermal plasma models, with either single- or multi-temperature plasmas. These models are compatible with the X-ray emission originating in the boundary layer between an accretion disk and a white dwarf. The high plasma temperatures of kT > 3 keV for all five targets were greater than expected for colliding winds. Based on these high temperatures as well as previous measurements of UV variability and UV luminosity and the large amplitude of X-ray flickering in 4 Dra, we conclude that all five sources are accretion-powered through predominantly optically thick boundary layers. Our X-ray data allow us to observe a small optically thin portion of the emission from these boundary layers. Given the time between previous observations and these observations, we find that the intrinsic X-ray flux and the intervening absorbing column can vary by factors of three or more on a timescale of years. However, the location of the absorber and the relationship between changes in accretion rate and absorption are still elusive.

  8. X-ray and neutron emission studies in a new Filippov type plasma focus

    Energy Technology Data Exchange (ETDEWEB)

    Babazadeh, A.R.; Banoushi, A. [Technical University of Amirkabir, Tehran (Iran, Islamic Republic of). Dept. of Physics; Roshan, M.V.; Habibi, H.; Nasiry, A.; Memarzadeh, M.; Lamehi, M.; Kiai, S.M. Sadat [Atomic Energy Organization of Iran (AEOI), Tehran (Iran, Islamic Republic of). Nuclear Fusion Research Center

    2002-03-01

    We have performed experimental comparative studies of the X-ray and neutron emission generated by the new Filippov-type plasma focus 'Dena', (90 kJ, 25 kV, 288{mu}F) in the pressure range of 0.6-1 torr. Time-integrated and time-resolved detectors, together with an X-ray pin-hole camera, along with a Be filter of 10{mu}m thickness have been used. For a working gas of neon and a at insert anode, the maximum soft and hard X-rays (SXR-HXR) yield obtained was 16 V and 1.5 V/shot over a 4{pi} solid angle, respectively, for a charging voltage range of 16-20 kV. As for the argon gas, the similar results such as 3.5 and 2 V/shot have been found, leading to a total conversion efficiency of X-ray emission of 0.09 % (for neon) and 0.03 % (for argon) of the stored energy. These efficiencies have been improved by the employment of a conic insert anode up to 0.4% and 0.1%. With deuterium puffing gas and a at insert anode, the maximum emission yield has been found to be 2.5 V for SXR and 1 V for HXR/shot which produce an ultimate emission profile width (FWHM) of 70-90 ns for X-rays and neutrons, giving rise to a maximum neutron yield of 1.2 x 10{sup 9}. Nevertheless, the maximum yield has been increased up to 5.5 times with the conic insert anode. In order to increase the neutron yield, we have introduced a krypton admixture to the deuterium filling gas and found that, for a krypton pressure of about 0.1 torr, the neutron yield increases by a factor of 3.5 for the flat insert and 1.5 for the conic insert anodes. (author)

  9. Dense plasma focus PACO as a hard X-ray emitter: a study on the radiation source

    OpenAIRE

    Supán, L.; Guichón, S.; Milanese, Maria Magdalena; Niedbalski, Jorge Julio; Moroso, Roberto Luis; Acuña, H.; Malamud, Florencia

    2016-01-01

    The radiation in the X-ray range detected outside the vacuum chamber of the dense plasma focus (DPF) PACO, are produced on the anode zone. The zone of emission is studied in a shot-to-shot analysis, using pure deuterium as filling gas. We present a diagnostic method to determine the place and size of the hard X-ray source by image analysis of high density radiography plates. Fil: Supán, L.. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Insti...

  10. Prepulse dependence in hard x-ray generation from microdroplets

    International Nuclear Information System (INIS)

    Anand, M.; Kahaly, S.; Kumar, G. Ravindra; Sandhu, A. S.; Gibbon, P.; Krishnamurthy, M.

    2006-01-01

    We report on experiments which show that liquid microdroplets are very efficient in hard x-ray generation. We make a comparative study of hard x-ray emission from 15 μm methanol microdroplets and a plain slab target of similar atomic composition at similar laser intensities. The hard X-ray yield from droplet plasmas is about 35 times more than that obtained from solid plasmas. A prepulse that is about 10ns and at least 2% in intensity of the main pulse is essential for hard x-ray generation from the droplets at about 1015 W cm-2. A hot electron temperature of 36 keV is measured from the droplets at 8 x 1014 W cm-2; three times higher intensity is needed to obtain similar hot electron temperature from solid plasmas that have similar atomic composition. We use 1D-PIC simulation to obtain qualitative correlation to the experimental observations

  11. Temporal feature of X-ray laser plasma observed from 3ω0/2, 2ω0 harmonic emission

    International Nuclear Information System (INIS)

    Li Wenhong; Mei Qiyong; Zhao Xuewei; Chen Yuting; Chunyu Shutai

    1995-01-01

    Temporal feature of X-ray laser plasma density was observed from 3ω 0 /2, 2ω 0 harmonic emission in the experiments. The temporal feature of 3ω 0 /2 harmonic emission of the germanium film is much different from that of the slab germanium target. The production of x-ray laser is closely related to 3ω 0 /2 harmonic emission in the slab germanium targets

  12. Plasma-based X-ray laser at 21 nm for multidisciplinary applications

    Czech Academy of Sciences Publication Activity Database

    Mocek, Tomáš; Rus, Bedřich; Kozlová, Michaela; Polan, Jiří; Homer, Pavel; Jakubczak, Krzysztof; Stupka, Michal; Snopek, David; Nejdl, Jaroslav; Edwards, M.H.; Whittaker, D.S.; Tallents, G. J.; Mistry, P.; Pert, G. J.; Booth, N.; Zhai, Z.; Fajardo, M.; Zeitoun, P.; Chalupský, Jaromír; Hájková, Věra; Juha, Libor

    2009-01-01

    Roč. 54, č. 2 (2009), s. 439-444 ISSN 1434-6060 R&D Projects: GA AV ČR KAN300100702; GA ČR GA202/05/2316; GA MŠk(CZ) LC528; GA ČR GC202/07/J008; GA MŠk(CZ) 7E08094; GA MŠk(CZ) 7E09092 EU Projects: European Commission(XE) 506350 - LASERLAB-EUROPE Institutional research plan: CEZ:AV0Z10100523 Keywords : x-ray laser * laser ablation * microstruturing * dense plasma probing Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.420, year: 2009

  13. Experimental studies and modeling of X-Rays multilayer mirrors damages under high X-Ray flux generated by a laser-plasma experiment; Etude experimentale et modelisation de l`endommagement des miroirs multicouches X soumis a de hauts flux de rayonnement X dans le cadre de l`experience plasma-laser

    Energy Technology Data Exchange (ETDEWEB)

    Le Guern, F

    1996-05-24

    We have been able with this work to point out characterize X-Rays multilayers mirrors damages. We have designed two experimental set-up which have been installed in the HELIOTROPE experimental chamber of the OCTAL facility located at the CEA in Limeil-Valenton. We have demonstrated that X-Rays multilayer mirrors properties were drastically modified by X-Rays emitted by a golden laser plasma. We have, more precisely, introduced the damage speed concept to quantify the expansion of the multilayer mirror period. We have been able to classify different multilayer mirrors in function of their resistance to damage and we have demonstrated that a silicate layer deposited on a mirror allowed to increase his resistance to damage. In a second part we have developed a simulation tool in order to simulate the X-Rays multilayer mirrors optical properties modifications. We have therefore coupled a thermo-mechanic code with an optical program. The results of the simulations are in a rather good agreement with the experiments and can be used to predict, before experiments, the multilayer mirror behavior under X-Rays irradiation. (author) 55 refs.

  14. A comparative study of the ionic keV X-ray line emission from ...

    Indian Academy of Sciences (India)

    resolved X-ray diffraction [15] etc. High conversion efficiency of the laser ... picosecond ionic X-ray pulses are produced when both the plasma density and the tem- ..... X-ray spectrum of magnesium plasma produced using femtosecond laser.

  15. Electron bunch diagnostics for laser-plasma accelerators, from THz to X-rays

    International Nuclear Information System (INIS)

    Plateau, G.

    2011-10-01

    This thesis presents a series of single-shot non-intrusive diagnostics of key attributes of electron bunches produced by a laser-plasma accelerator (LPA). Three injection mechanisms of the LPA are characterized: channeled and self-guided self-injection, plasma down-ramp injection, and two-beam colliding pulse injection. New diagnostic techniques are successfully demonstrated: up to 8 times higher sensitivity wavefront sensor-based plasma density measurements, strong spatio-temporal coupling of the focused THz pulse is demonstrated using the temporal electric-field cross-correlation (TEX) of a long chirped probe with a short probe and confirms the two-component structure of the bunch observed by electron spectrometry, and normalized transverse emittances as low as 0.1 mm mrad are demonstrated for 0.5 GeV-class beams produced in a capillary-guided LPA by characterizing the betatron radiation emitted by the electrons inside the plasma using a new single-shot X-ray spectroscopy technique. (author)

  16. Investigation of HF-plasma-treated soft x-ray optical elements

    Science.gov (United States)

    Eggenstein, F.; Krivenkov, M.; Rudolph, I.; Sertsu, M. G.; Sokolov, A.; Varykhalov, A.; Wolf, J.; Zeschke, T.; Schäfers, F.

    2017-09-01

    The contamination of optical elements (mirrors and gratings) with carbon still is an issue when using soft x-ray synchrotron radiation. With an in-house developed HF-plasma treatment we are able to decontaminate our optics in-situ from carbon very efficiently. The cleaning device, a simple Al-antenna, is mounted in situ inside the mirror- and grating vacuum chambers. A systematic study of the HF-plasma cleaning efficiency was performed acquired with in-situ and exsitu methods for monitoring: An atomic force microscope (AFM) and a scanning tunneling microscope (STM) were used before and after the cleaning process to determine the surface morphology and roughness. Reflectivity angular scans using the reflectometer at the BESSY-II Metrology Station [1-3] allowed to estimate the thickness of the remaining Clayer after different cleaning steps and thereby helped us to determine the etching rate. Reflection spectra measurements in the range of 200 eV - 900 eV show the complete removal of Carbon from the optics without contaminating it with any other elements due to the plasma treatment. The data show that the plasma process improves the reflectivity and reduces the roughness of the surface. In addition to that, the region of the optical surface where the carbon has been removed becomes passivated.

  17. SphinX x-ray spectrophotometer

    Science.gov (United States)

    Kowaliński, Mirosław

    2012-05-01

    This paper presents assumptions to a PhD thesis. The thesis will be based on the construction of Solar Photometer in X-rays (SphinX). SphinX was an instrument developed to detect the soft X-rays from the Sun. It was flown on board the Russian CORONAS-Photon satellite from January 30, 2009 to the end of November, 2009. During 9 months in orbit SphinX provided an excellent and unique set of observations. It revealed about 750 flares and brightenings. The instrument observed in energy range 1.0 - 15.0 keV with resolution below ~0.5 keV. Here, the SphinX instrument objectives, design, performance and operation principle are described. Below results of mechanical and thermal - vacuum tests necessary to qualify the instrument to use in space environment are presented. Also the calibration results of the instrument are discussed. In particular detail it is described the Electrical Ground Support Equipment (EGSE) for SphinX. The EGSE was used for all tests of the instrument. At the end of the paper results obtained from the instrument during operation in orbit are discussed. These results are compared with the other similar measurements performed from the separate spacecraft instruments. It is suggested design changes in future versions of SphinX.

  18. DNA strand breaks induced by soft X-ray pulses from a compact laser plasma source

    Czech Academy of Sciences Publication Activity Database

    Adjei, D.; Wiechec, A.; Wachulak, P.; Ayele, M. G.; Lekki, J.; Kwiatek, W. M.; Bartnik, A.; Davídková, Marie; Vyšín, Luděk; Juha, Libor; Pina, L.; Fiedorowicz, H.

    2016-01-01

    Roč. 120, MAR (2016), s. 17-25 ISSN 0969-806X R&D Projects: GA ČR GA13-28721S; GA ČR(CZ) GBP108/12/G108 EU Projects: European Commission(XE) 284464 - LASERLAB-EUROPE Institutional support: RVO:68378271 ; RVO:61389005 Keywords : laser-produced plasma * soft X-rays * radiobiology * gas puff target * water window * DNA strand break Subject RIV: BO - Biophysics Impact factor: 1.315, year: 2016

  19. X-ray High-resolution Spectroscopy for Laser-produced Plasma

    Science.gov (United States)

    Barbato, F.; Scarpellini, D.; Malizia, A.; Gaudio, P.; Richetta, M.; Antonelli, L.

    The study of the emission spectrum gives information about the material generating the spectrum itself and the condition in which this is generated. The wavelength spectra lines are linked to the specific element and plasma conditions (electron temperature, density), while their shape is influenced by several physical effects like Stark and Doppler ones. In this work we study the X-ray emission spectra of a copper laser-produced plasma by using a spherical bent crystal spectrometer to measure the electron temperature. The facility used is the laser TVLPS, at the Tor Vergata University in Rome. It consists of a Nd:Glass source (in first harmonic - 1064 nm) whose pulse parameters are: 8 J in energy, time duration of 15 ns and a focal spot diameter of 200 μm. The adopted spectrometer is based on a spherical bent crystal of muscovite. The device combines the focusing property of a spherical mirror with the Bragg's law. This allows to obtain a great power resolution but a limited range of analysis. In our case the resolution is on average 80 eV. As it is well-known, the position of the detector on the Rowland's circle is linked to the specific spectral range which has been studied. To select the area to be investigated, we acquired spectra by means of a flat spectrometer. The selected area is centered on 8.88 Å. To calibrate the spectrum we wrote a ray-tracing MATLAB code, which calculates the detector alignment parameters and calibration curve. We used the method of line ratio to measure the electron temperature. This is possible because we assumed the plasma to be in LTE condition. The temperature value was obtained comparing the experimental one, given by the line ratio, with the theoret