Nova diagnostics summary

International Nuclear Information System (INIS)

Slivinsky, V.W.; Drake, R.P.

1985-01-01

The authors intend that Nova be the best diagnosed ICF research facility in operation today. The authors experience in providing advanced diagnostics for previous laser systems will be extended at Nova, and will be challenged by the development of new instrumentation to diagnose the more advanced targets made possible by this powerful laser. Previous experience has shown that to understand target performance, the authors must have as complete a set of diagnostics as possible. The Nova diagnostics are divided into two sets: the basic set required for the initial Nova experiments and the more advanced set for later, generally more complex, experiments. The basic set will be operational for the first Nova shots; it was a Nova line item funded with Nova construction money. This basic set is presented in a table

Nova control system: goals, architecture, and system design

International Nuclear Information System (INIS)

Suski, G.J.; Duffy, J.M.; Gritton, D.G.; Holloway, F.W.; Krammen, J.R.; Ozarski, R.G.; Severyn, J.R.; Van Arsdall, P.J.

1982-01-01

The control system for the Nova laser must operate reliably in a harsh pulse power environment and satisfy requirements of technical functionality, flexibility, maintainability and operability. It is composed of four fundamental subsystems: Power Conditioning, Alignment, Laser Diagnostics, and Target Diagnostics, together with a fifth, unifying subsystem called Central Controls. The system architecture utilizes a collection of distributed microcomputers, minicomputers, and components interconnected through high speed fiber optic communications systems. The design objectives, development strategy and architecture of the overall control system and each of its four fundamental subsystems are discussed. Specific hardware and software developments in several areas are also covered

Nova target diagnostics control system

International Nuclear Information System (INIS)

Severyn, J.R.

1985-01-01

During the past year the Nova target diagnostics control system was finished and put in service. The diagnostics loft constructed to the north of the target room provides the environmental conditions required to collect reliable target diagnostic data. These improvements include equipment cooling and isolation of the power source with strict control of instrumentation grounds to eliminate data corruption due to electromagnetic pulses from the laser power-conditioning system or from target implosion effects

Precision operation of the Nova laser for fusion experiments

International Nuclear Information System (INIS)

Caird, J.A.; Ehrlich, R.B.; Hermes, G.L.; Landen, O.L.; Laumann, C.W.; Lerche, R.A.; Miller, J.L.; Murray, J.E.; Nielsen, N.D.; Powell, H.T.; Rushford, M.C.; Saunders, R.L.; Thompson, C.E.; VanArsdall, P.J.; Vann, C.S.; Weiland, T.L.

1994-01-01

The operation of a Neodymium glass laser of a special design for fusion experiments is improved by a better pulse synchronization, the gain stabilization, and the laser diagnostics. We used sensor upgrading and antifriction coating of focusing lenses. The pointing accuracy of the Nova laser meets now our goal for precision operation. (AIP) copyright 1994 American Institute of Physics

Nova Event Logging System

International Nuclear Information System (INIS)

Calliger, R.J.; Suski, G.J.

1981-01-01

Nova is a 200 terawatt, 10-beam High Energy Glass Laser currently under construction at LLNL. This facility, designed to demonstrate the feasibility of laser driven inertial confinement fusion, contains over 5000 elements requiring coordinated control, data acquisition, and analysis functions. The large amounts of data that will be generated must be maintained over the life of the facility. Often the most useful but inaccessible data is that related to time dependent events associated with, for example, operator actions or experiment activity. We have developed an Event Logging System to synchronously record, maintain, and analyze, in part, this data. We see the system as being particularly useful to the physics and engineering staffs of medium and large facilities in that it is entirely separate from experimental apparatus and control devices. The design criteria, implementation, use, and benefits of such a system will be discussed

Experience with a high order programming language on the development of the Nova distributed control system

International Nuclear Information System (INIS)

Suski, G.J.; Holloway, F.W.; Duffy, J.M.

1983-01-01

This paper explores the impact of an HOL on the development of the distributed computer control system for Nova laser fusion facility. As the world's most powerful glass laser, Nova will generate 150 trillion watt pulses of infrared light focused onto fusion targets a few millimeters in diameter. It will perform experiments designed to explore the feasibility of fusion as an energy source of the future. Nova will utilize fifty microcomputers and four VAX-11/780's in a distributed process control computer system architecture

Experience with a high order programming language on the development of the Nova distributed control system

Energy Technology Data Exchange (ETDEWEB)

Suski, G.J.; Holloway, F.W.; Duffy, J.M.

1983-05-10

This paper explores the impact of an HOL on the development of the distributed computer control system for Nova laser fusion facility. As the world's most powerful glass laser, Nova will generate 150 trillion watt pulses of infrared light focused onto fusion targets a few millimeters in diameter. It will perform experiments designed to explore the feasibility of fusion as an energy source of the future. Nova will utilize fifty microcomputers and four VAX-11/780's in a distributed process control computer system architecture.

Hydrodynamic instability experiments on the Nova laser

International Nuclear Information System (INIS)

Remington, B.A.; Glendinning, S.G.; Kalantar, D.H.

1996-08-01

Hydrodynamic instabilities in compressible plasmas play a critical role in the fields of inertial confinement fusion (ICF), astrophysics, and high energy-density physics. We are, investigating hydrodynamic instabilities such as the Rayleigh-Taylor (RT) instability, at high compression at the Nova laser in a series of experiments, both in planar and in spherical geometry. In the indirect drive approach, a thermal x-ray drive is generated by focusing the Nova laser beams into a Au cylindrical radiation cavity (hohlraum). Issues in the instability evolution that we are examining are shock propagation and foil compression, RT growth of 2D versus 3D single-mode perturbations, drive pulse shape, perturbation location at the ablation front versus at an embedded interface, and multimode perturbation growth and nonlinear saturation. The effects of convergence on RT growth are being investigated both with hemispherical implosions of packages mounted on the hohlraum wall and with spherical implosions of capsules at the center of the hohlraum. Single-mode perturbations are pre-imposed at the ablation front of these capsules as a seed for the RT growth. In our direct drive experiments, we are investigating the effect of laser imprinting and subsequent RT growth on planar foils, both at λ Laser = 1/3 μm and 1/2 μm. An overview is given describing recent progress in each of these areas

Summary of control and data acquisition systems for NOVA experiments (invited)

International Nuclear Information System (INIS)

McCauley, E.W.; Campbell, E.M.; Auerbach, J.M.; Montgomery, D.S.; Martin, V.A.; Randolph, J.E.; Shaw, J.G.; Stewart, B.L.; Stone, G.F.

1986-01-01

The NOVA laser has completed its first year of operation. During this period, emphasis has been placed on activation of the facility and of the numerous target and beam diagnostics. Two separate target chambers are in use. NOVA operation is separated into two broad functions: laser operations and experiments. The operations group provides the laser system control, operation, and data acquisition and the experiments group provides experiment definition, diagnostic instrumentation, and overall data processing. On the operations side, VAX 11/780 computers are used to set up diagnostic operating parameters and collect data recorded by the CAMAC and CCD modules. These data are delivered in files by electronic link to the Laser Experiments and Analysis Facility (LEAF) VAX 11/785 of the experiments group for processing. Film data are digitized at LEAF and the film data files are also processed on the LEAF VAX. The LEAF provides collection, processing, analysis, and archiving of the experimental data. The many applications software packages written for LEAF provide the experimental physicists and NOVA operations staff with programs and data bases for interpretation of experimental results. This software makes fundamental use of the ORACLE relational data base management system to both access the required data and archive the obtained results. Post-shot data processing produces sets of scalar values, x, y profiles and x, y, z contour data. The scalar data are stored in the ORACLE DB; the more extensive results are stored in binary files on disk. All data forms are accessed by a comprehensive software system, the electronic SHOTBOOK, developed around the ORACLE DBMS

Pulsed power supply for Nova Upgrade

International Nuclear Information System (INIS)

Bacon, J.L.; Kajs, J.P.; Walls, A.; Weldon, W.F.; Zowarka, R.C.

1992-01-01

This report describes work carried out at the Center for Electromechanics at The University of Texas at Austin (CEM-UT). A baseline design of the Nova Upgrade has been completed by Lawrence Livermore National Laboratory. The Nova Upgrade is an 18 beamline Nd: glass laser design utilizing fully relayed 4x4 30 cm aperture segmented optical components. The laser thus consists of 288 independent beamlets nominally producing 1.5 to 2.0 MJ of 0.35 μm light in a 3 to 5 ns pulse. The laser design is extremely flexible and will allow a wide range of pulses to irradiate ICF targets. This facility will demonstrate ignition/gain and the scientific feasibility of ICF for energy and defense applications. The pulsed power requirements for the Nova Upgrade are given. CEM-UT was contracted to study and develop a design for a homopolar generator/inductor (HPG/inductor) opening switch system which would satisfy the pulsed power supply requirements of the Nova Upgrade. The Nd:glass laser amplifiers used in the Nova Upgrade will be powered by light from xenon flashlamps. The pulsed power supply for the Nova Upgrade powers the xenon flashlamps. This design and study was for a power supply to drive flashlamps

High-energy 4ω probe laser for laser-plasma experiments at Nova

International Nuclear Information System (INIS)

Glenzer, S.H.; Weiland, T.L.; Bower, J.; MacKinnon, A.J.; MacGowan, B.J.

1999-01-01

For the characterization of inertial confinement fusion plasmas, we implemented a high-energy 4ω probe laser at the Nova laser facility. A total energy of >50 J at 4ω, a focal spot size of order 100 μm, and a pointing accuracy of 100 μm was demonstrated for target shots. This laser provides intensities of up to 3x10 14 Wcm -2 and therefore fulfills high-power requirements for laser-plasma interaction experiments. The 4ω probe laser is now routinely used for Thomson scattering. Successful experiments were performed in gas-filled hohlraums at electron densities of n e >2x10 21 cm -3 which represents the highest density plasma so far being diagnosed with Thomson scattering. copyright 1999 American Institute of Physics

Three wavelength optical alignment of the Nova laser

International Nuclear Information System (INIS)

Swift, C.D.; Bliss, E.S.; Jones, W.A.; Seppala, L.G.

1983-01-01

The Nova laser, presently under construction at Lawrence Livermore National Laboratory, will be capable of delivering more than 100 kJ of focused energy to an Inertial Confinement Fusion (ICF) target. Operation at the fundamental wavelength of the laser (1.05 μm) and at the second and third harmonic will be possible. This paper will discuss the optical alignment systems and techniques being implemented to align the laser output to the target at these wavelengths prior to each target irradiation. When experiments require conversion of the laser light to wavelengths of 0.53 μm and 0.35 μm prior to target irradiation, this will be accomplished in harmonic conversion crystals located at the beam entrances to the target chamber. The harmonic alignment system will be capable of introducing colinear alignment beams of all three wavelengths into the laser chains at the final spatial filter. The alignment beam at 1.05 μm will be about three cm in diameter and intense enough to align the conversion crystals. Beams at 0.53 μm and 0.35 μm will be expanded by the spatial filter to full aperture (74 cm) and used to illuminate the target and other alignment aids at the target chamber focus. This harmonic illumination system will include viewing capability as well. A final alignment sensor will be located at the target chamber. It will view images of the chamber focal plane at all three wavelengths. In this way, each beam can be aligned at the desired wavelength to produce the focal pattern required for each target irradiation. The design of the major components in the harmonic alignment system will be described, and a typical alignment sequence for alignment to a target will be presented

Composite polymer/glass edge claddings for new Nova laser disks

International Nuclear Information System (INIS)

Powell, H.T.; Campbell, J.H.; Edwards, G.

1987-01-01

Large Nd:glass laser disks like those used in Nova require an edge cladding which absorbs at 1 μm. This cladding prevents Fresnel reflections from the edges from causing parasitic oscillations which would otherwise reduce the gain. The original Nova disks had a Cu/sup 2+/-doped phosphate glass cladding which was cast at high temperature around the circumference of the disk. Although the performance of this cladding is excellent, it was expensive to produce. Consequently, in parallel with their efforts to develop Pt inclusion-free laser glass, the authors developed a composite polymer/glass edge cladding that can be applied at greatly reduced cost. Laser disks constructed with the new cladding design show identical performance to the previous Nova disks and have been tested for hundreds of shots without degradation. The new cladding consists of absorbing glass strips which are bonded to the edges of polygonal-rather that elliptical-shaped disks. The bond is made by an --25-μm thick clear epoxy adhesive whose index of refraction matches both the laser and absorbing glass. By blending aromatic and aliphatic epoxy constituents, they achieved an index-of-refraction match within approximately +-0.003 between the epoxy and glass. The epoxy was also chosen based on its damage resistance to flashlamp light and its adhesive strength to glass. The present cladding is a major improvement over a previous experimental cladding utilizing silicone rubber as a coupling agent. Early prototypes constructed without using the presented techniques exhibited failures from both mechanisms. Delamination failures occurred which clearly showed both surface and bulk-mode parasitic oscillation. Requirements on the polymer, disk size, and Nd doping to prevent these problems are presented

Thermal stress in the edge cladding of Nova glass laser disks

International Nuclear Information System (INIS)

Pitts, J.H.; Kong, M.K.; Gerhard, M.A.

1987-01-01

We calculated thermal stresses in Nova glass laser disks having light-absorbing edge cladding glass attached to the periphery with an epoxy adhesive. Our closed-form solutions indicated that, because the epoxy adhesive is only 25 μm across, it does not significantly affect the thermal stress in the disk or cladding glass. Our numerical results showed a peak tensile stress in the cladding glass of 24 MPa when the cladding glass had a uniform absorption coefficient of 7.5 cm -1 . This peak value is reduced to 19 MPa if surface parasitic oscillation heating is eliminated by tilting the disk edges. The peak tensile stresses exceed the typical 7 to 14-MPa working stress for glass; however, we have not observed any disk or cladding glass failures at peak Nova fluences of 20 J/cm 2 . We have observed delamination of the epoxy adhesive bond at fluences several times that which would occur on Nova. Replacement laser disks will incorporate cladding with a reduced absorption coefficient of 4.5 cm -1 . Recent experiments show that this reduced absorption coefficient is satisfactory

Shock-hydrodynamics experiments on the Nova laser

International Nuclear Information System (INIS)

Miller, P.; Peyser, T.; Stry, P.; Budil, K.; Wojtowicz, D.; Burke, E.

1995-08-01

We have conducted shock-induced hydrodynamics experiments using the Nova laser at Lawrence Livermore National Laboratory. The laser provides a high-enthalpy source by depositing its energy (about 22 kJ) in a small gold cavity called a Hohlraum. The Hohlraum serves as a driver section, launching very strong (M ∼ 20) shocks into millimeter-scale cylindrical ''shock tubes.'' The flow is imaged radiographically by an electronic framing camera, using a laser-generated x-ray source. Several topics have been addressed with this configuration, including shock-induced mixing at density interfaces (seeded with a variety of perturbations); the development of high-speed, shaped-charge-like jets; the effects of geometry on the planarity of the generated shocks; and shock-shock interactions which develop in the flows. This paper describes the general configuration of our experiments, presents an overview of the high-speed jet work, discusses some of our findings, and compares our results with computer simulations

Nova target experiments

International Nuclear Information System (INIS)

Drake, R.P.

1985-11-01

The Nova laser, at the Lawrence Livermore National Laboratory, provides unique opportunities for target experiments. It has unprecedented energy on target and significant flexibility. The paper presented by John Hunt described the capabilities and the status of Nova. This paper discusses plans for future experiments using Nova, and the present status of target experiments. We plan to perform high-quality physics experiments that exploit the unique capabilities of Nova. Because this is our goal, we are fielding an extensive array of well-characterized target diagnostics to measure the emissions from the target. The first section of this paper discusses the basic target diagnostics. We are also taking care to quantify the performance of the laser

Optical components for the Nova laser

International Nuclear Information System (INIS)

Wallerstein, E.P.; Baker, P.C.; Brown, N.J.

1982-01-01

In addition to its other characteristics, the Nova Laser Fusion facility may well be the largest precision optical project ever undertaken. Moreover, during the course of construction, concurrent research and development has been successfully conducted, and has resulted in significant advances in various technical areas, including manufacturing efficiency. Although assembly of the first two beams of Nova is just commencing, the optical production, including construction of the special facilities required for many of the components, has been underway for over three years, and many phases of the optical manufacturing program for the first 10 beams will be completed within the next two years. On the other hand, new requirements for second and third harmonic generation have created the need to initiate new research and development. This work has been accomplished through the enormous cooperation DOE/LLNL has received from commercial industry on this project. In many cases, industry, where much of the optical component research and development and virtually all of the manufacturing is being done, has made substantial investment of its own funds in facilities, equipment, and research and development, in addition to those supplied by DOE/LLNL

Engineering design of the Nova Laser Facility for inertial-confinement fusion

International Nuclear Information System (INIS)

Simmons, W.W.; Godwin, R.O.; Hurley, C.A.

1982-01-01

The design of the Nova Laser Facility for inertial confinement fusion experiments at Lawrence Livermore National Laboratory is presented from an engineering perspective. Emphasis is placed upon design-to-performance requirements as they impact the various subsystems that comprise this complex experimental facility

The use of beam propagation modeling of Beamlet and Nova to ensure a ''safe'' National Ignition Facility laser system design

International Nuclear Information System (INIS)

Henesian, M.A.; Renard, P.; Auerbach, J.

1997-01-01

An exhaustive set of Beamlet and Nova laser system simulations were performed over a wide range of power levels in order to gain understanding about the statistical trends in Nova and Beamlet's experimental data sets, and to provide critical validation of propagation tools and design ''rules'' applied to the 192-arm National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL). The experiments considered for modeling were at 220-ps FWHM duration with unpumped booster slabs on Beamlet, and 100-ps FWHM with pumped 31.5-cm and 46-cm disk amplifiers on Nova. Simulations indicated that on Beamlet, the AB (the intensity pendent phase shift parameter characterizing the tendency towards beam filamentation) for the booster amplifier stage without pumping, would be nearly identical to the AB expected on NIF at the peak of a typical 20-ns long shaped pulse intended for ICF target irradiation. Therefore, with energies less than I kJ in short-pulses, we examined on Beamlet the comparable AB-driven filamentation conditions predicted for long ICF pulseshapes in the 18 kJ regime on the NIF, while avoiding fluence dependent surface damage. Various spatial filter pinhole configurations were examined on Nova and Beamlet. Open transport spatial filter pinholes were used in some experiments to allow the direct measurement of the onset of beam filamentation. Schlieren images on Beamlet of the far field irradiance measuring the scattered light fraction outside of 33-microradians were also obtained and compared to modeled results

Assurance management program for the 30 Nova laser fusion project

International Nuclear Information System (INIS)

Levy, A.J.

1983-01-01

The Nova assurance management program was developed using the quality assurance (QA) approach first implemented at LLNL in early 1978. The LLNL QA program is described as an introduction to the Nova assurance management program. The Nova system is described pictorially through the Nova configuration, subsystems and major components, interjecting the QA techniques which are being pragmatically used to assure the successful completion of the project

Requirements and new materials for fusion laser systems

International Nuclear Information System (INIS)

Stokowski, S.E.; Weber, M.J.; Saroyan, R.A.; Hagen, W.F.

1977-10-01

Higher focusable power in neodymium glass fusion lasers can be obtained through the use of new materials with lower nonlinear index (n 2 ) and better energy storage capabilities than the presently employed silicate glass. Silicate, phosphate, fluorophosphate, and beryllium fluoride glasses are discussed in terms of fusion laser requirements, particularly those for the proposed Nova laser. Examples of the variation in spectroscopic and optical properties obtainable with compositional changes are given. Results of a system evaluation of potential laser materials show that fluorophosphate glasses have many of the desired properties for use in Nova. These glasses are now being cast in large sizes (30-cm diameter) and will be tested in prototype amplifiers in 1978

Requirements and new materials for fusion laser systems

Energy Technology Data Exchange (ETDEWEB)

Stokowski, S.E.; Weber, M.J.; Saroyan, R.A.; Hagen, W.F.

1977-10-01

Higher focusable power in neodymium glass fusion lasers can be obtained through the use of new materials with lower nonlinear index (n/sub 2/) and better energy storage capabilities than the presently employed silicate glass. Silicate, phosphate, fluorophosphate, and beryllium fluoride glasses are discussed in terms of fusion laser requirements, particularly those for the proposed Nova laser. Examples of the variation in spectroscopic and optical properties obtainable with compositional changes are given. Results of a system evaluation of potential laser materials show that fluorophosphate glasses have many of the desired properties for use in Nova. These glasses are now being cast in large sizes (30-cm diameter) and will be tested in prototype amplifiers in 1978.

Mechanical design for a large fusion laser system

International Nuclear Information System (INIS)

Hurley, C.A.

1979-01-01

The Nova Mechanical Systems Group at LLL is responsible for the design, fabrication, and installation of all laser chain components, for the stable support structure that holds them, and for the beam lines that transport the laser beam to the target system. This paper is an overview of the group's engineering effort, emphasizing new developments

Solid-state disk amplifiers for fusion-laser systems

Energy Technology Data Exchange (ETDEWEB)

Martin, W.E.; Trenholme, J.B.; Linford, G.J.; Yarema, S.M.; Hurley, C.A.

1981-09-01

We review the design, performance, and operation of large-aperture (10 to 46 cm) solid-state disk amplifiers for use in laser systems. We present design data, prototype tests, simulations, and projections for conventional cylindrical pump-geometry amplifiers and rectangular pump-geometry disk amplifiers. The design of amplifiers for the Nova laser system is discussed.

Design and implementation of a financial planning and tracking system for the Nova Project

International Nuclear Information System (INIS)

Holcomb, F.

1982-01-01

The Nova project is a 185 million dollar DOE funded project to build an experimental facility to demonstrate the thermonuclear ignition of laser fusion targets. This paper describes the design and implementation considerations for the project's computerized performance measurement financial planning and tracking system and critiques its actual operation

Development of construction specifications to attain clean rooms for the NOVA laser facility

International Nuclear Information System (INIS)

Benedix, C.P.

1980-02-01

This paper describes the process of defining technical requirements for a major Department of Energy Research and Development Facility and subsequent development of construction specifications for the clean spaces in that facility. The organizational interactions between technical client, Engineering and Construction elements are described. The importance of an interdisciplinary team approach is stressed. A brief description of the SHIVA Laser and NOVA Laser Clean Spaces is included to indicate the scope of the facility undertaking. A number of potential pitfalls are discussed that may be helpful to designers of new facilities

Producing National Ignition Facility (NIF)-quality beams on the Nova and Beamlet lasers

International Nuclear Information System (INIS)

Widmayer, C.C.; Auerbach, J.M.; Ehrlich, R.B.

1996-08-01

The Nova and Beamlet lasers were used to simulate the beam propagation conditions that will be encountered during the National Ignition Facility operation. Perturbation theory predicts that there is a 5mm scale length propagation mode that experiences large nonlinear power growth. This mode was observed in the tests. Further tests have confirmed that this mode can be suppressed with improved spatial filtering

Petawatt laser and target irradiation system at LLNL

International Nuclear Information System (INIS)

Pennington, D.M.; Perry, M.D.; Britten, J.A.; Brown, C.G.; Herman, S.; Homer, J.; Miller, J.L.; Stuart, B.C.; Tietbohl, G.; Van Lue, J.; Yanovsky, V.

1997-01-01

In May, 1996, we demonstrated the production over a petawatt of peak power in the Nova/Petawatt Laser Facility, generating 620 J in ∼ 430 fs. Results of the first focused irradiance tests, and recent deployment of a novel targeting system will be presented

Nova chain design and performance

International Nuclear Information System (INIS)

Simmons, W.W.; Glaze, J.A.; Trenholme, J.B.; Hagen, W.F.

1980-01-01

During the past year design of the Nova laser has undergone significant change as a result of developments in our laser glass and optical coating evaluation programs. Two notable aspects of the glass development program deserve emphasis. First, vendor qualification for production of fluorophosphate laser glass is progressing satisfactorily. There is a reasonable expectation that vendors can meet fluorophosphate glass specifications within Nova schedule constraints. Secondly, recent gain saturation measurements have shown that the saturation fluence of the fluorophosphate glass is larger than previously supposed (approx. 5.5 J/cm 2 ) and in fact is somewhat larger than Shiva silicate glasses. Hence, performance of Nova for pulses in the 3 ns and longer range should be satisfactory. For pulses in the 1 ns regime, of course, the fluorophosphate chain will have superior performance to that of silicate because of its low nonlinear index of refraction (approx. 30% that of silicate). These and other considerations have led us to choose a chain design based upon the use of fluorophosphate glass in our amplifiers

ORIGINS OF ABSORPTION SYSTEMS OF CLASSICAL NOVA V2659 CYG (NOVA CYG 2014)

Energy Technology Data Exchange (ETDEWEB)

Arai, A.; Kawakita, H. [Koyama Astronomical Observatory, Kyoto Sangyo University, Motoyama, Kamigamo, Kita-ku, Kyoto 603-8555 (Japan); Shinnaka, Y. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Tajitsu, A., E-mail: arai6a@cc.kyoto-su.ac.jp [Subaru Telescope, National Astronomical Observatory of Japan, 650 North A’ohoku Place, Hilo, Hawaii 96720 (United States)

2016-10-10

We report on high-dispersion spectroscopy results of a classical nova V2659 Cyg (Nova Cyg 2014) that are taken 33.05 days after the V -band maximum. The spectrum shows two distinct blueshifted absorption systems originating from H i, Fe ii, Ca ii, etc. The radial velocities of the absorption systems are −620 km s{sup −1}, and −1100 to −1500 km s{sup −1}. The higher velocity component corresponds to the P-Cygni absorption features frequently observed in low-resolution spectra. Much larger numbers of absorption lines are identified at the lower velocity. These mainly originate from neutral or singly ionized Fe-peak elements (Fe i, Ti ii, Cr ii, etc.). Based on the results of our spectroscopic observations, we discuss the structure of the ejecta of V2659 Cyg. We conclude that the low- and high-velocity components are likely to be produced by the outflow wind and the ballistic nova ejecta, respectively.

Development of composite polymer-glass edge claddings for Nova Laser Disks

International Nuclear Information System (INIS)

Campbell, J.H.; Edwards, G.; Frick, F.A.; Gemmell, D.S.; Gim, B.M.; Jancaitis, K.S.; Jessop, E.S.; Kong, M.K.; Lyon, R.E.; Murray, J.E.; Patton, H.G.; Pitts, J.H.; Powell, H.T.; Riley, M.O.; Wallerstein, E.P.; Wolfe, C.R.; Woods, B.W.

1988-01-01

Large Nd:glass laser disks for disk amplifiers require an edge cladding which absorbs at 1 μ m. This cladding prevents edge reflections from causing parasitic oscillations that would otherwise deplete the gain. The authors have developed a composite polymer-glass edge cladding that consists of absorbing glass strips bonded to the edges of laser glass disks using an epoxy adhesive. The edge cladding must survive a fluence of approximately 20 J/cm 2 in a 0.5-ms pulse. Failure can occur either by decomposition of the polymer or by mechanical failure from thermal stresses which leads to bond delamination. An epoxy has been developed that gives the required damage resistance, refractive index match and processing characteristics. A slight tilt of the disk edges greatly reduces the threat from parasitic oscillations and a glass surface treatment is used to promote bond adhesion. Laser disks fabricated with this new cladding show identical gain performance to disks using conventional fused-glass cladding and have been tested for over 2000 shots (equivalent to about a 4-year lifetime on Nova) with out degradation

Evaluation of dynamic range for LLNL streak cameras using high contrast pulsed and pulse podiatry on the Nova laser system

International Nuclear Information System (INIS)

Richards, J.B.; Weiland, T.L.; Prior, J.A.

1990-01-01

This paper reports on a standard LLNL streak camera that has been used to analyze high contrast pulses on the Nova laser facility. These pulses have a plateau at their leading edge (foot) with an amplitude which is approximately 1% of the maximum pulse height. Relying on other features of the pulses and on signal multiplexing, we were able to determine how accurately the foot amplitude was being represented by the camera. Results indicate that the useful single channel dynamic range of the instrument approaches 100:1

Stability design considerations for mirror support systems in ICF lasers

International Nuclear Information System (INIS)

Tietbohl, G.L.; Sommer, S.C.

1996-10-01

Some of the major components of laser systems used for Inertial Confinement Fusion (ICF) are the large aperture mirrors which direct the path of the laser. These mirrors are typically supported by systems which consist of mirror mounts, mirror enclosures, superstructures, and foundations. Stability design considerations for the support systems of large aperture mirrors have been developed based on the experience of designing and evaluating similar systems at the Lawrence Livermore National Laboratory (LLNL). Examples of the systems developed at LLNL include Nova, the Petawatt laser, Beamlet, and the National Ignition Facility (NIF). The structural design of support systems of large aperture mirrors has typically been controlled by stability considerations in order for the large laser system to meet its performance requirements for alignment and positioning. This paper will discuss the influence of stability considerations and will provide guidance on the structural design and evaluation of mirror support systems in ICF lasers so that this information can be used on similar systems

High density implosion experiments at Nova

International Nuclear Information System (INIS)

Cable, M.D.; Hatchett, S.P.; Nelson, M.B.; Lerche, R.A.; Murphy, T.J.; Ress, D.B.

1994-01-01

Deuterium filled glass microballoons are used as indirectly driven targets for implosion experiments at the Nova Laser Fusion Facility. High levels of laser precision were required to achieve fuel densities and convergences to an ignition scale hot spot. (AIP) copyright 1994 American Institute of Physics

Computer simulations of laser hot spots and implosion symmetry kiniform phase plate experiments on Nova

International Nuclear Information System (INIS)

Peterson, R. R.; Lindman, E. L.; Delamater, N. D.; Magelssen, G. R.

2000-01-01

LASNEX computer code simulations have been performed for radiation symmetry experiments on the Nova laser with vacuum and gas-filled hohlraum targets [R. L. Kauffman et al., Phys. Plasmas 5, 1927 (1998)]. In previous experiments with unsmoothed laser beams, the symmetry was substantially shifted by deflection of the laser beams. In these experiments, laser beams have been smoothed with Kiniform Phase Plates in an attempt to remove deflection of the beams. The experiments have shown that this smoothing significantly improves the agreement with LASNEX calculations of implosion symmetry. The images of laser produced hot spots on the inside of the hohlraum case have been found to differ from LASNEX calculations, suggesting that some beam deflection or self-focusing may still be present or that emission from interpenetrating plasmas is an important component of the images. The measured neutron yields are in good agreement with simulations for vacuum hohlraums but are far different for gas-filled hohlraums. (c) 2000 American Institute of Physics

Preliminary performance and ICF target experiments with Nova

International Nuclear Information System (INIS)

Drake, R.P.

1985-11-01

In December 1984, the Nova facility fired all ten laser arms, converted the output 1.05 micron energy to 0.35 micron light, and focused the 0.35 micron light through a 4 mm pinhole in the ten-beam target chamber. Since that time, a two-beam target chamber has been added, the performance of the laser evaluated, and preparation has been made for target experiments. This paper summarizes the performance of Nova and describes progress and plans for target experiments

Implementation of 40-ps high-speed gated-microchannel-plate based x-ray framing cameras on reentrant SIM's for Nova

International Nuclear Information System (INIS)

Bell, P.M.; Kilkenny, J.D.; Landen, O.; Bradley, D.K.

1994-01-01

Gated framing cameras used in diagnosing laser produced plasmas have been used on the Nova laser system since 1987. There have been many variations of these systems implemented. All of these cameras have been ultimately limited in response time for two reasons. One being the electrical gating amplitude verses the gate width, this has always limited the detectable gain in the system. The second being the length to diameter (l/d) ratio of standard off the shelf microchannel plates (MCP). This sets the minimum electrical gate pulse that will give detectable gain from a given microchannel plate. The authors have implemented two different types of 40 ps framing camera configurations on the Nova laser system. They will describe the configurations of both systems as well as discuss the advantages of each

The classical nova outburst

International Nuclear Information System (INIS)

Starrfield, S.G.

1988-01-01

The classical nova outburst occurs on the white dwarf component in a close binary system. Nova systems are members of the general class of cataclysmic variables and other members of the class are the Dwarf Novae, AM Her variables, Intermediate Polars, Recurrent Novae, and some of the Symbiotic variables. Although multiwavelength observations have already provided important information about all of these systems, in this review I will concentrate on the outbursts of the classical and recurrent novae and refer to other members of the class only when necessary. 140 refs., 1 tab

Demonstration of efficient full-aperture type I/type II third harmonic conversion on Nova

International Nuclear Information System (INIS)

Wegner, P.J.; Henesian, M.A.; Marchi, F.T.; Speck, D.R.

1988-01-01

The ten arms of the Nova laser system readily deliver 22.5 kJ of third harmonic radiation in 1-ns pulses to targets for fusion experiments. Frequency conversion experiments conducted on a single arm have produced >7.5 kJ of 3ω radiation in longer (2.5-ns) pulses at the output of a Nova crystal array with 15 kJ of 1ω drive. Equivalent on-target energies (40-60 kJ) in 2-3-ns pulses is available at target chamber center when the laser disks in the output section of the Nova amplifier are replaced with new high-damage threshold glass. The remaining issue facing frequency conversion on Nova is to demonstrate similar 3-ω energy (>40 kJ) on-target at shorter (1-ns) pulse lengths with controlled pulse shape at 1→ drive energies up to 9 kJ. Frequency conversion to 40 kJ of 3→ with precisely shaped pulses is required for future experiments. The authors assembled a full-aperture (74-cm) array of these crystals to test on an arm outfitted with the new laser glass. Measurements of conversion efficiency, pulse time history, and optical quality of the converted beam are reported

Large laser system facility design

International Nuclear Information System (INIS)

Gilmartin, T.J.

1983-01-01

Optical stability of foundations and support structures, environmental control, close-in subsystem integration, spatial organization, materiel flow and access to remote subsystems is discussed and compared for four laser facilities: The Special Isotope Separation Laboratory, Argus, Shiva/Nova, and Firepond

High Energy Neutrino Physics with NOvA

Energy Technology Data Exchange (ETDEWEB)

Coan, Thomas [Southern Methodist Univ. , Dallas, TX (United States)

2016-09-09

Knowledge of the position of energy deposition in “hit” detector cells of the NOvA neutrino detector is required by algorithms for pattern reconstruction and particle identification necessary to interpret the raw data. To increase the accuracy of this process, the majority of NOvA's 350 000 far detector cell shapes, including distortions, were measured as they were constructed. Using a special laser scanning system installed at the site of the NOvA far detector in Ash River, MN, we completed algorithmic development and measured shape parameters for the far detector. The algorithm and the measurements are “published” in NOνA’s document database (doc #10389, “Cell Center Finder for the NOνA Far Detector Modules”).

NOVA integrated alignment/diagnostic sensors

International Nuclear Information System (INIS)

1978-01-01

Under Contract 3772003 to the Lawrence Livermore Laboratory, Aerojet ElectroSystems Company has investigated a number of alignment system design topics for the NOVA and SHIVA upgrade lasers. Prior reports dealt with the Main Beam Alignment System, and with Multipass Amplifier Alignment Concepts. This report, which completes the contract, examines ways in which the Return Beam Diagnostic (RBD) package and Incident Beam Diagnostic (IBD) packages may be reconfigured to a more integrated package. In particular, the report shows that the RBD optics may be directly integrated in the Pointing Focus and Centering (PFC) sensor, and that the IBD optics may use the same basic common configuration as the PFC/RBD package

Evaluation of dynamic range for LLNL streak cameras using high contrast pulses and pulse podiatry'' on the Nova laser system

Energy Technology Data Exchange (ETDEWEB)

Richards, J.B.; Weiland, T.L.; Prior, J.A.

1990-07-01

A standard LLNL streak camera has been used to analyze high contrast pulses on the Nova laser facility. These pulses have a plateau at their leading edge (foot) with an amplitude which is approximately 1% of the maximum pulse height. Relying on other features of the pulses and on signal multiplexing, we were able to determine how accurately the foot amplitude was being represented by the camera. Results indicate that the useful single channel dynamic range of the instrument approaches 100:1. 1 ref., 4 figs., 1 tab.

Target area for Nova upgrade: Containing ignition and beyond

International Nuclear Information System (INIS)

Tobin, M.T.; Smith, J.R.; Campbell, D.; Wong, D.K.; Sullivan, J.A.; Pendergrass, J.; Weinstein, B.; Klein, M.

1991-01-01

The Lawrence Livermore National Laboratory (LLNL) is developing a conceptual design for upgrading the Nova laser from ∼ 50 kJ to ∼ 1.8 MJ of laser energy at a wavelength of 351 nm. Anticipated target performance includes achieving ignition and possibly fusion yields to 20 MJ. The target area design represents a unique challenge since it will be operating in a regime where first wall ablation and optics damage are major issues for the first time in an ICF facility. Here we describe potential performance criteria for the facility and anticipated yield-dependent x-ray, neutron, shrapnel, and debris environments. We also briefly describe the different systems that make up the target area and discuss some of the design issues. The insignificant environmental impact Nova Upgrade (NU) operations is anticipated to have on the laboratory and surrounding area is discussed. Finally, alternate design options are described along with their potential benefits

Implementation and performance of beam smoothing on 10 beams of the Nova Laser

International Nuclear Information System (INIS)

Pennington, D.M.

1997-01-01

Recent simulations and experiments on Nova indicate that some level of smoothing may be required to suppress filamentation in plasmas on the National Ignition Facility (NIF), resulting in the addition of 1-D smoothing capability to the current baseline design. Control of stimulated Brillouin scattering (SBS) and filamentation is considered essential to the success of laser fusion because they affect the amount and location of laser energy delivered to the x-ray conversion region (hohlraum wall) for indirect drive and to the absorptive region for direct drive, Smoothing by spectral dispersion (SSD)[1], reduces these instabilities by reducing nonuniformities in the focal irradiance when averaged over a finite time interval. We have installed SSD on Nova to produce beam smoothing on all 10 beam lines. A single dispersion grating is located in a position common to all 10 beam lines early in the preamplifier chain. This location limits the 1 ω bandwidth to 2.2 (angstrom) with sufficient dispersion to displace the speckle field of each frequency component at the target plane by one half speckle diameter. Several beam lines were modified to allow orientation of the dispersion on each arm relative to the hohlraum wall. After conversion to the third harmonic the beam passes through a kinoform phase plate (KPP) designed to produce an elliptical spot at best focus. The KPPs produce a focal spot having an elliptical flat-top envelope with a superimposed speckle pattern. Over 93% of the energy is contained in the central 400 km. Calculations indicate a 16% rms. intensity variance will be reached after 330 ps for a single beam

Symbiotic Novae

OpenAIRE

Mikolajewska, Joanna

2010-01-01

The symbiotic novae are thermonuclear novae in symbiotic binary systems -- interacting binaries with evolved red giant donors, and the longest orbital periods. This paper aims at presenting physical characteristics of these objects and discussing their place among the whole family of symbiotic stars.

Laser program annual report, 1977. Volume 1

Energy Technology Data Exchange (ETDEWEB)

Bender, C.F.; Jarman, B.D. (eds.)

1978-07-01

An overview is given of the laser fusion program. The solid-state program covers the Shiva and Nova projects. Laser components, control systems, alignment systems, laser beam diagnostics, power conditioning, and optical components are described. The fusion experimental program concerns the diagnostics and data acquisition associated with Argus and Shiva. (MOW)

Laser program annual report, 1977. Volume 1

International Nuclear Information System (INIS)

Bender, C.F.; Jarman, B.D.

1978-07-01

An overview is given of the laser fusion program. The solid-state program covers the Shiva and Nova projects. Laser components, control systems, alignment systems, laser beam diagnostics, power conditioning, and optical components are described. The fusion experimental program concerns the diagnostics and data acquisition associated with Argus and Shiva

Simulations of laser imprint for Nova experiments and for ignition capsules. Revision 1

International Nuclear Information System (INIS)

Weber, S.V.; Glendinning, S.G.; Kalantar, D.H.; Key, M.H.; Remington, B.A.; Rothenberg, J.L.; Wolfrum, E.; Verdon, C.P.; Knauer, J.P.

1996-12-01

In direct drive ICF, nonuniformities in laser illumination seed ripples at the ablation front in a process called ''imprint''. These nonuniformities grow during the capsule implosion and, if initially large enough, can penetrate the capsule shell, impede ignition, or degrade burn. Imprint has been simulated for recent experiments performed on the Nova laser at LLNL examining a variety of beam smoothing conditions. Most used laser intensities similar to the early part of an ignition capsule pulse shape, 1 ≅ 10 13 W/cm 2 . The simulations matched most of the measurements of imprint modulation. The effect of imprint upon National Ignition Facility (NIF) direct drive ignition capsules has also been simulated. Imprint is predicted to give modulation comparable to an intrinsic surface finish of ∼10 nm RMS. Modulation growth was examined using the Haan [Phys. Rev. A 39, 5812 (1989)] model, with linear growth factors as a function of spherical harmonic mode number obtained from an analytic dispersion relation. Ablation front amplitudes are predicted to become substantially nonlinear, so that saturation corrections are large. Direct numerical simulations of two-dimensional multimode growth were also performed. The capsule shell is predicted to remain intact, which gives a basis for believing that ignition can be achieved. 27 refs., 10 figs

Solid state laser technology for inertial confinement fusion: A collection of articles from ''Energy and Technology Review''

International Nuclear Information System (INIS)

1988-06-01

This paper contains reprinted articles that record several milestones in laser research at LLNL. ''Neodymium-Glass Laser Research and Development at LLNL'' recounts the history of the Laser Program and our work on neodymium-glass lasers. ''Nova Laser Technology'' describes the capabilities of the Nova laser and some of its uses. ''Building Nova: Industry Relations and Technology Transfer'' illustrates the Laboratory's commitment to work with US industry in technology development. ''Managing the Nova Laser Project'' details the organization and close monitoring of costs and schedules during the construction of the Nova laser facility. The article ''Optical Coatings by the Sol-Gel Process,'' describes our chemical process for making the damage-resistant, antireflective silica coatings used on the Nova laser glass. The technical challenges in designing and fabricating the KDP crystal arrays used to convert the light wave frequency of the Nova lasers are reported in ''Frequency Conversion of the Nova Laser.'' Two articles, ''Eliminating Platinum Inclusions in Laser Glass'' and ''Detecting Microscopic Inclusions in Optical Glass,'' describe how we dealt with the problem of damaging metal inclusions in the Nova laser glass. The last article reprinted here, ''Auxilliary Target Chamber for Nova,'' discusses the diversion of two of Nova's ten beamlines into a secondary chamber for the purpose of increasing our capacity for experimentation

RECURRENT NOVAE IN M31

Energy Technology Data Exchange (ETDEWEB)

Shafter, A. W. [Department of Astronomy, San Diego State University, San Diego, CA 92182 (United States); Henze, M. [European Space Astronomy Centre, P.O. Box 78, E-28692 Villanueva de la Cañada, Madrid (Spain); Rector, T. A. [Department of Physics and Astronomy, University of Alaska Anchorage, 3211 Providence Dr., Anchorage, AK 99508 (United States); Schweizer, F. [Carnegie Observatories, 813 Santa Barbara St., Pasadena, CA 91101 (United States); Hornoch, K. [Astronomical Institute, Academy of Sciences, CZ-251 65 Ondřejov (Czech Republic); Orio, M. [Astronomical Observatory of Padova (INAF), I-35122 Padova (Italy); Pietsch, W. [Max Planck Institute for Extraterrestrial Physics, P.O. Box 1312, Giessenbachstr., D-85741, Garching (Germany); Darnley, M. J.; Williams, S. C.; Bode, M. F. [Astrophysics Research Institute, Liverpool John Moores University, Liverpool L3 5RF (United Kingdom); Bryan, J., E-mail: aws@nova.sdsu.edu [McDonald Observatory, Austin, TX 78712 (United States)

2015-02-01

The reported positions of 964 suspected nova eruptions in M31 recorded through the end of calendar year 2013 have been compared in order to identify recurrent nova (RN) candidates. To pass the initial screen and qualify as a RN candidate, two or more eruptions were required to be coincident within 0.′1, although this criterion was relaxed to 0.′15 for novae discovered on early photographic patrols. A total of 118 eruptions from 51 potential RN systems satisfied the screening criterion. To determine what fraction of these novae are indeed recurrent, the original plates and published images of the relevant eruptions have been carefully compared. This procedure has resulted in the elimination of 27 of the 51 progenitor candidates (61 eruptions) from further consideration as RNe, with another 8 systems (17 eruptions) deemed unlikely to be recurrent. Of the remaining 16 systems, 12 candidates (32 eruptions) were judged to be RNe, with an additional 4 systems (8 eruptions) being possibly recurrent. It is estimated that ∼4% of the nova eruptions seen in M31 over the past century are associated with RNe. A Monte Carlo analysis shows that the discovery efficiency for RNe may be as low as 10% that for novae in general, suggesting that as many as one in three nova eruptions observed in M31 arise from progenitor systems having recurrence times ≲100 yr. For plausible system parameters, it appears unlikely that RNe can provide a significant channel for the production of Type Ia supernovae.

Perspective : component tracking on the Nova system

International Nuclear Information System (INIS)

MacDonald, S.

1999-01-01

The issue of introducing Component Tracking as a service to natural gas producers, shippers and straddle plant operators was discussed. Approximately 39 companies in the industry were contacted by consultants at Nova Gas Transmission in an effort to assess if introducing this service would add value to individual producers. The numerous implications that may have to be dealt with if Component Tracking is introduced were also described. Component Tracking would provide an equitable approach to the allocation of molecules in the gas stream, and could provide producers with the ability to avoid capital outlay in field plants by alternatively contracting for recovery of the liquids at the straddle plants. Component Tracking is to be voluntary and each shipper would be able to decide whether to utilize the service at each of their receipt points onto the Nova system

A four-color beam smoothing irradiation system for laser-plasma interaction experiments at LLNL

International Nuclear Information System (INIS)

Pennington, D.M.; Henesian, M.A.; Wilcox, R.B.; Weiland, T.L.; Eimerl, D.; Ehrlich, R.B.; Laumann, C.W.; Miller, J.L.

1995-01-01

A novel four-color beam smoothing scheme with a capability similar to that planned for the proposed National Ignition Facility has been deployed on the Nova laser, and has been successfully used for laser fusion experiments. Wavefront aberrations in high power laser systems produce nonuniformities in the energy distribution of the focal spot that can significantly degrade the coupling of the energy into a fusion target, driving various plasma instabilities. The introduction of temporal and spatial incoherence over the face of the beam using techniques such as smoothing by spectral dispersion (SSD) can reduce these variation in the focal irradiance when averaged over a finite time interval. We developed a multiple frequency source that is spatially separated into four quadrants, each containing a different central frequency. Each quadrant is independently converted to the third harmonic in a four-segment Type I/ Type II KDP crystal array with independent phase-matching for efficient frequency conversion. Up to 2.3 kJ of third harmonic light is generated in a 1 ns pulse, corresponding to up to 65% conversion efficiency. SSD is implemented by adding limited frequency modulated bandwidth to each frequency component. Smoothing by spectral dispersion is implemented during the spatial separation of the FM modulated beams to provide additional smoothing, reaching a 16% rms intensity variation level. The four- color system was successfully used to probe NIF-like plasmas, producing 2x10 15 W/cm 2 . This paper discusses the detailed implementation and performance of the segmented four-color system on the Nova laser system

Long-term cycles in old Novae

International Nuclear Information System (INIS)

Shara, M.M.; Potter, M.; Shara, D.J.

1989-01-01

Three of the oldest recovered novae were monitored with a CCD camera almost nightly for six weeks. The cyclic variability reported by Della Valle and Rosino (1987) for Nova Oph 1848 is confirmed. A similar variability is also suggested for Nova Cyg 1876, though this system exhibits more random flickering than Nova Oph. No secular variability is seen in Nova Sge 1783. 12 refs

Nova Upgrade program: ignition and beyond

International Nuclear Information System (INIS)

Storm, E.; Campbell, E.M.; Hogan, W.J.; Lindl, J.D.

1993-01-01

The Lawrence Livermore National Laboratory (LLNL) Inertial Confinement Fusion (ICF) Program is addressing the critical physics and technology issues directed toward demonstrating and exploiting ignition and propagating burn to high gain with ICF targets for both defense and civilian applications. Nova is the primary U.S. facility employed in the study of the X-ray-driven (indirect drive) approach to ICF. Nova's principal objective is to demonstrate that laser-driven hohlraums can achieve the conditions of driver-target coupling efficiency, driver irradiation symmetry, driver pulseshaping, target preheat, and hydrodynamic stability required by hot-spot ignition and fuel compression to realize a fusion gain. (author)

Laser program annual report, 1980

International Nuclear Information System (INIS)

Coleman, L.W.; Krupke, W.F.; Strack, J.R.

1981-06-01

Volume 1 provides a Program Overview, presenting highlights of the technical accomplishments of the elements of the Program, a summary of activities carried out under the Glass Laser Experiments Lead Laboratory Program, as well as discussions of Program resources and facilities. Section 2, also in the first volume, covers the work on solid state Nd:glass lasers, including systems operations, Nova and Novette system development, and supporting research and development activities

Laser program annual report, 1980

Energy Technology Data Exchange (ETDEWEB)

Coleman, L.W.; Krupke, W.F.; Strack, J.R. (eds.)

1981-06-01

Volume 1 provides a Program Overview, presenting highlights of the technical accomplishments of the elements of the Program, a summary of activities carried out under the Glass Laser Experiments Lead Laboratory Program, as well as discussions of Program resources and facilities. Section 2, also in the first volume, covers the work on solid state Nd:glass lasers, including systems operations, Nova and Novette system development, and supporting research and development activities.

Modeling of large aperture third harmonic frequency conversion of high power Nd:glass laser systems

International Nuclear Information System (INIS)

Henesian, M.A.; Wegner, P.J.; Speck, D.R.; Bibeau, C.; Ehrlich, R.B.; Laumann, C.W.; Lawson, J.K.; Weiland, T.L.

1991-01-01

To provide high-energy, high-power beams at short wavelengths for inertial-confinement-fusion experiments, we routinely convert the 1.053-μm output of the Nova, Nd:phosphate-glass, laser system to its third-harmonic wavelength. We describe performance and conversion efficiency modeling of the 3 x 3 arrays potassium-dihydrogen-phosphate crystal plates used for type II/type II phase-matched harmonic conversion of Nova 0.74-m diameter beams, and an alternate type I/type II phase-matching configuration that improves the third-harmonic conversion efficiency. These arrays provide energy conversion of up to 65% and intensity conversion to 70%. 19 refs., 11 figs

Physics of laser fusion. Volume III. High-power pulsed lasers

International Nuclear Information System (INIS)

Holzrichter, J.F.; Eimerl, D.; George, E.V.; Trenholme, J.B.; Simmons, W.W.; Hunt, J.T.

1982-09-01

High-power pulsed lasers can deliver sufficient energy on inertial-confinement fusion (ICF) time scales (0.1 to 10 ns) to heat and compress deuterium-tritium fuel to fusion-reaction conditions. Several laser systems have been examined, including Nd:glass, CO 2 , KrF, and I 2 , for their ICF applicability. A great deal of developmental effort has been applied to the Nd:glass laser and the CO 2 gas laser systems; these systems now deliver > 10 4 J and 20 x 10 12 W to ICF targets. We are constructing the Nova Nd:glass laser at LLNL to provide > 100 kJ and > 100 x 10 12 W of 1-μm radiation for fusion experimentation in the mid-1980s. For ICF target gain > 100 times the laser input, we expect that the laser driver must deliver approx. 3 to 5 MJ of energy on a time scale of 10 to 20 ns. In this paper we review the technological status of fusion-laser systems and outline approaches to constructing high-power pulsed laser drivers

Novae news

CERN Document Server

2012-01-01

As announced in the previous Bulletin, Novae has opened a new snack bar on the Flagstaff car park, just a few metres from CERN's reception area (Building 33).   Just a few metres from the CERN Reception, the new Novae snack point welcomes visitors and CERNois. Opening hours Currently: Monday to Friday, 8 a.m. to 4 p.m. From September: Monday to Friday, 7:45 a.m. to 5 p.m.; Saturdays from 8 a.m. to 2 p.m. The snack bar selection includes breakfast, starting at 2.70 CHF, cold dishes from 5 CHF, and hot dishes from 6 CHF.   Novae has also installed a 24-hour-a-day food vending machine in the CERN hostel (Building 39) and in Building 13. You can buy pasta and cooked dishes for 6.50 CHF to 8 CHF. In addition, a groceries vending machine has been installed in the main building, just across from the news kiosk. Nearly 60 different items are available around the clock. Finally, Novae has introduced a new payment system in several buildings on the Meyrin site. It accepts credit ca...

Characterization of X-ray streak cameras for use on Nova

International Nuclear Information System (INIS)

Kalantar, D.H.; Bell, P.M.; Costa, R.L.; Hammel, B.A.; Landen, O.L.; Orzechowski, T.J.; Hares, J.D.; Dymoke-Bradshaw, A.K.L.

1996-09-01

There are many different types of measurements that require a continuous time history of x-ray emission that can be provided with an x-ray streak camera. In order to properly analyze the images that are recorded with the x-ray streak cameras operated on Nova, it is important to account for the streak characterization of each camera. We have performed a number of calibrations of the streak cameras both on the bench as well as with Nova disk target shots where we use a time modulated laser intensity profile (self-beating of the laser) on the target to generate an x-ray comb. We have measured the streak camera sweep direction and spatial offset, curvature of the electron optics, sweep rate, and magnification and resolution of the electron optics

Nova performance at ultra high fluence levels

International Nuclear Information System (INIS)

Hunt, J.T.

1986-01-01

Nova is a ten beam high power Nd:glass laser used for interial confinement fusion research. It was operated in the high power high energy regime following the completion of construction in December 1984. During this period several interesting nonlinear optical phenomena were observed. These phenomena are discussed in the text. 11 refs., 5 figs

AT Cnc: A SECOND DWARF NOVA WITH A CLASSICAL NOVA SHELL

International Nuclear Information System (INIS)

Shara, Michael M.; Mizusawa, Trisha; Zurek, David; Wehinger, Peter; Martin, Christopher D.; Neill, James D.; Forster, Karl; Seibert, Mark

2012-01-01

We are systematically surveying all known and suspected Z Cam-type dwarf novae for classical nova shells. This survey is motivated by the discovery of the largest known classical nova shell, which surrounds the archetypal dwarf nova Z Camelopardalis. The Z Cam shell demonstrates that at least some dwarf novae must have undergone classical nova eruptions in the past, and that at least some classical novae become dwarf novae long after their nova thermonuclear outbursts, in accord with the hibernation scenario of cataclysmic binaries. Here we report the detection of a fragmented 'shell', 3 arcmin in diameter, surrounding the dwarf nova AT Cancri. This second discovery demonstrates that nova shells surrounding Z Cam-type dwarf novae cannot be very rare. The shell geometry is suggestive of bipolar, conical ejection seen nearly pole-on. A spectrum of the brightest AT Cnc shell knot is similar to that of the ejecta of the classical nova GK Per, and of Z Cam, dominated by [N II] emission. Galaxy Evolution Explorer FUV imagery reveals a similar-sized, FUV-emitting shell. We determine a distance of 460 pc to AT Cnc, and an upper limit to its ejecta mass of ∼5 × 10 –5 M ☉ , typical of classical novae.

AT Cnc: A SECOND DWARF NOVA WITH A CLASSICAL NOVA SHELL

Energy Technology Data Exchange (ETDEWEB)

Shara, Michael M.; Mizusawa, Trisha; Zurek, David [Department of Astrophysics, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024-5192 (United States); Wehinger, Peter [Steward Observatory, the University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Martin, Christopher D.; Neill, James D.; Forster, Karl [Department of Physics, Math and Astronomy, California Institute of Technology, 1200 East California Boulevard, Mail Code 405-47, Pasadena, CA 91125 (United States); Seibert, Mark [Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)

2012-10-20

We are systematically surveying all known and suspected Z Cam-type dwarf novae for classical nova shells. This survey is motivated by the discovery of the largest known classical nova shell, which surrounds the archetypal dwarf nova Z Camelopardalis. The Z Cam shell demonstrates that at least some dwarf novae must have undergone classical nova eruptions in the past, and that at least some classical novae become dwarf novae long after their nova thermonuclear outbursts, in accord with the hibernation scenario of cataclysmic binaries. Here we report the detection of a fragmented 'shell', 3 arcmin in diameter, surrounding the dwarf nova AT Cancri. This second discovery demonstrates that nova shells surrounding Z Cam-type dwarf novae cannot be very rare. The shell geometry is suggestive of bipolar, conical ejection seen nearly pole-on. A spectrum of the brightest AT Cnc shell knot is similar to that of the ejecta of the classical nova GK Per, and of Z Cam, dominated by [N II] emission. Galaxy Evolution Explorer FUV imagery reveals a similar-sized, FUV-emitting shell. We determine a distance of 460 pc to AT Cnc, and an upper limit to its ejecta mass of {approx}5 Multiplication-Sign 10{sup -5} M {sub Sun }, typical of classical novae.

Discovery of a New Classical Nova Shell Around a Nova-like Cataclysmic Variable

Science.gov (United States)

Guerrero, Martín A.; Sabin, Laurence; Tovmassian, Gagik; Santamaría, Edgar; Michel, Raul; Ramos-Larios, Gerardo; Alarie, Alexandre; Morisset, Christophe; Bermúdez Bustamante, Luis C.; González, Chantal P.; Wright, Nick J.

2018-04-01

The morphology and optical spectrum of IPHASX J210204.7+471015, a nebula classified as a possible planetary nebula are, however, strikingly similar to those of AT Cnc, a classical nova shell around a dwarf nova. To investigate its true nature, we have obtained high-resolution narrowband [O III] and [N II] images and deep optical spectra. The nebula shows an arc of [N II]-bright knots notably enriched in nitrogen, while an [O III]-bright bow shock is progressing throughout the ISM. Diagnostic line ratios indicate that shocks are associated with the arc and bow shock. The central star of this nebula has been identified by its photometric variability. Time-resolved photometric and spectroscopic data of this source reveal a period of 4.26 hr, which is attributed to a binary system. The optical spectrum is notably similar to that of RW Sex, a cataclysmic variable star (CV) of the UX UMa nova-like (NL) type. Based on these results, we propose that IPHASX J210204.7 + 471015 is a classical nova shell observed around a CV-NL system in quiescence.

Laser fusion program overview

International Nuclear Information System (INIS)

Emmett, J.L.

1977-01-01

This program is structured to proceed through a series of well defined fusion milestones to proof of the scientific feasibility, of laser fusion with the Shiva Nova system. Concurrently, those key technical areas, such as advanced lasers, which are required to progress beyond proof of feasibility, are being studied. We have identified and quantified the opportunities and key technical issues in military applications, such as weapons effects simulations, and in civilian applications, such as central-station electric power production. We summarize the current status and future plans for the laser fusion program at LLL, emphasizing the civilian applications of laser fusion

NOVA.

Science.gov (United States)

WGBH-TV, Boston, MA.

News clippings, reviews, and feature articles about the Public Broadcasting System science-adventure series "Nova" are collected here. Included are comments from the New York Times, Washington Post, Christian Science Monitor, and TV Guide. Commentaries are primarily favorable and include synopses of various episodes. (DGC)

Research and development of improving the pumping efficiency of phosphate laser glass: Final report

International Nuclear Information System (INIS)

Izumitani, T.

1985-01-01

It is well known that Pt inclusion in laser glass remarkably lowers the damage threshold by laser beam. Present commercial laser glasses are produced so as to minimize the Pt inclusion. However, the damage due to small Pt inclusion, which has never seriously caused the laser damage in a lower fluence level, is getting to be a problem as the output fluence of laser increases. In NOVA system, most of laser glasses were damaged at fluence of 3 to 4 J/cm 2 . Since NOVA has been planned to operate at 10 J/cm 2 , this damage threshold is absolutely unacceptable and it should be increased. In this report we will show the basic conception to make a Pt inclusion free glass and its experimental results

Aberrations and focusability in large solid-state-laser systems

International Nuclear Information System (INIS)

Simmons, W.W.

1981-01-01

Solid state lasers for fusion experiments must reliably deliver maximum power to small (approximately .5 mm) targets from stand-off focal distances of 1 m or more. This requirement places stringent limits upon the optical quality of the several major components - amplifiers, Faraday isolators, spatial filters - in each amplifier train. Residual static aberrations in optical components are transferred to the beam as it traverses the optical amplifier chain. Although individual components are typically less than lambda/20 for components less than 10 cm clear aperture; and less than lambda/10 for components less than 20 cm clear aperture; the large number of such components in optical series results in a wavefront error that may exceed one wave for modern solid state lasers. For pulse operation, the focal spot is additionally broadened by intensity dependent nonlinearities. Specific examples of the performance of large aperture components will be presented within the context of the Argus and Shiva laser systems, which are presently operational at Lawrence Livermore National Laboratory. Design requirements upon the larger aperture Nova laser components, up to 74 cm in clear aperture, will also be discussed; these pose a significant challenge to the optical industry

The NOvA Data Acquistion System: A highly distributed, synchronized, continuous readout system for a long baseline neutrino experiment

CERN Multimedia

CERN. Geneva

2012-01-01

The NOvA experiment at Fermi National Accelerator Lab, has been designed and optimized to perform a suite of measurements critical to our understanding of the neutrino’s properties, their oscillations and their interactions. NOvA presents a unique set of data acquisition and computing challenges due to the immense size of the detectors, the data volumes that are generated through the continuous digitization of the frontend systems, and the need to buffer the full data stream to allow for highly asynchronous triggering and extraction of physics events. These challenges are compounded by the stringent timing and synchronization requirements that are placed on the acquisition systems by the need to precisely correlate information between the accelerator complex and the remote detector locations. The NOvA Data Acquisition system has been designed and built to meets these challenges. The system utilizes a highly modular, novel acquisition and event building scheme, which has been deployed on a large hierarch...

Large aperture components for solid state laser fusion systems

International Nuclear Information System (INIS)

Simmons, W.W.

1978-01-01

Solid state lasers for fusion experiments must reliably deliver maximum power to small (approximately .5 mm) targets from stand-off focal distances of 1 m or more. This requirement places stringent limits upon the optical quality, resistance to damage, and overall performance of the several major components--amplifiers, Faraday isolators, spatial filters--in each amplifier train. Component development centers about achieving (1) highest functional material figure of merit, (2) best optical quality, and (3) maximum resistance to optical damage. Specific examples of the performance of large aperture components will be presented within the context of the Argus and Shiva laser systems, which are presently operational at Lawrence Livermore Laboratory. Shiva comprises twenty amplifiers, each of 20 cm output clear aperture. Terawatt beams from these amplifiers are focused through two opposed, nested clusters of f/6 lenses onto such targets. Design requirements upon the larger aperture Nova laser components, up to 35 cm in clear aperture, will also be discussed; these pose a significant challenge to the optical industry

Fabrication and testing of gas filled targets for large scale plasma experiments on Nova

International Nuclear Information System (INIS)

Stone, G.F.; Spragge, M.; Wallace, R.J.; Rivers, C.J.

1995-01-01

An experimental campaign on the Nova laser was started in July 1993 to study one st of target conditions for the point design of the National Ignition Facility (NIF). The targets were specified to investigate the current NIF target conditions--a plasma of ∼3 keV electron temperature and an electron density of ∼1.0 E + 21 cm -3 . A gas cell target design was chosen to confine as gas of ∼0.01 cm 3 in volume at ∼ 1 atmosphere. This paper will describe the major steps and processes necessary in the fabrication, testing and delivery of these targets for shots on the Nova Laser at LLNL

Interaction of Supernova Remnants with Interstellar Clouds: From the Nova Laser to the Galaxy

International Nuclear Information System (INIS)

Klein, Richard I.; Budil, Kimberly S.; Perry, Theodore S.; Bach, David R.

2000-01-01

The interaction of strong shock waves, such as those generated by the explosion of supernovae with interstellar clouds, is a problem of fundamental importance in understanding the evolution and the dynamics of the interstellar medium (ISM) as it is disrupted by shock waves. The physics of this essential interaction sheds light on several key questions: (1) What is the rate and total amount of gas stripped from the cloud, and what are the mechanisms responsible? (2) What is the rate of momentum transfer to the cloud? (3) What is the appearance of the shocked cloud, its morphology and velocity dispersion? (4) What is the role of vortex dynamics on the evolution of the cloud? (5) Can the interaction result in the formation of a new generation of stars? To address these questions, one of us has embarked on a comprehensive multidimensional numerical study of the shock cloud problem using high-resolution adaptive mesh refinement (AMR) hydrodynamics. Here we present the results of a series of Nova laser experiments investigating the evolution of a high-density sphere embedded in a low-density medium after the passage of a strong shock wave, thereby emulating the supernova shock-cloud interaction. The Nova laser was utilized to generate a strong (∼Mach 10) shock wave which traveled along a miniature beryllium shock tube, 750 μm in diameter, filled with a low-density plastic emulating the ISM. Embedded in the plastic was a copper microsphere (100 μm in diameter) emulating the interstellar cloud. Its morphology and evolution as well as the shock wave trajectory were diagnosed via side-on radiography. We describe here experimental results of this interaction for the first time out to several cloud crushing times and compare them to detailed two- and three-dimensional radiation hydrodynamic simulations using both arbitrary Lagrangian and Eulerian hydrodynamics (ALE) as well as high-resolution AMR hydrodynamics. We briefly discuss the key hydrodynamic instabilities

Pulsed power supplies for laser flashlamps. Final report

International Nuclear Information System (INIS)

Bird, W.L. Jr.; Driga, M.D.; Mayhall, D.J.T.; Brennan, M.

1978-10-01

A preliminary engineering design of a compensated pulse alternator for driving laser flashlamps is presented. The work performed by the Center for Electromechanics at The University of Texas at Austin also includes the optimization and revision of the prototype design for a compensated pulse alternator power supply for the NOVA laser system at Lawrence Livermore Laboratory

NOvA Event Building, Buffering and Data-Driven Triggering From Within the DAQ System

International Nuclear Information System (INIS)

Fischler, M; Rechenmacher, R; Green, C; Kowalkowski, J; Norman, A; Paterno, M

2012-01-01

The NOvA experiment is a long baseline neutrino experiment design to make precision probes of the structure of neutrino mixing. The experiment features a unique deadtimeless data acquisition system that is capable acquiring and building an event data stream from the continuous readout of the more than 360,000 far detector channels. In order to achieve its physics goals the experiment must be able to buffer, correlate and extract the data in this stream with the beam-spills that occur that Fermilab. In addition the NOvA experiment seeks to enhance its data collection efficiencies for rare class of event topologies that are valuable for calibration through the use of data driven triggering. The NOvA-DDT is a prototype Data-Driven Triggering system. NOvA-DDT has been developed using the Fermilab artdaq generic DAQ/Event-building toolkit. This toolkit provides the advantages of sharing online software infrastructure with other Intensity Frontier experiments, and of being able to use any offline analysis module-unchanged-as a component of the online triggering decisions. We have measured the performance and overhead of NOvA-DDT framework using a Hough transform based trigger decision module developed for the NOvA detector to identify cosmic rays. The results of these tests which were run on the NOvA prototype near detector, yielded a mean processing time of 98 ms per event, while consuming only 1/16th of the available processing capacity. These results provide a proof of concept that a NOvA-DDT based processing system is a viable strategy for data acquisition and triggering for the NOvA far detector.

Laser program annual report, 1979

International Nuclear Information System (INIS)

Coleman, L.W.; Strack, J.R.

1980-03-01

This volume provides a program overview, presenting highlights of the technical accomplishments of the elements of the program, as well as discussions of program resources and facilities. Also covered are the work of the Solid-State Laser program element, which includes systems operations, Nova, and research and development activities

Design of a fiber optic multi-tapped computer bus for a pulsed power control system application

International Nuclear Information System (INIS)

Gritton, D.G.; Berkbigler, L.W.; Oicles, J.A.

1979-01-01

Control system techniques developed and proven on the Shiva laser have been extended to incorporate new electronic and electo-optic devices as well as conform to unique operational requirements of the 300 terawatt Nova laser system. This paper describes one segment of the control system being designed for the Nova laser currently under design/construction at Lawrence Livermore Laboratory. The specific segment covered is the control system bus structure responsible for power conditioning and real-time control functions

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

Identifying and quantifying recurrent novae masquerading as classical novae

International Nuclear Information System (INIS)

Pagnotta, Ashley; Schaefer, Bradley E.

2014-01-01

Recurrent novae (RNe) are cataclysmic variables with two or more nova eruptions within a century. Classical novae (CNe) are similar systems with only one such eruption. Many of the so-called CNe are actually RNe for which only one eruption has been discovered. Since RNe are candidate Type Ia supernova progenitors, it is important to know whether there are enough in our Galaxy to provide the supernova rate, and therefore to know how many RNe are masquerading as CNe. To quantify this, we collected all available information on the light curves and spectra of a Galactic, time-limited sample of 237 CNe and the 10 known RNe, as well as exhaustive discovery efficiency records. We recognize RNe as having (1) outburst amplitude smaller than 14.5 – 4.5 × log (t 3 ), (2) orbital period >0.6 days, (3) infrared colors of J – H > 0.7 mag and H – K > 0.1 mag, (4) FWHM of Hα > 2000 km s –1 , (5) high excitation lines, such as Fe X or He II near peak, (6) eruption light curves with a plateau, and (7) white dwarf mass greater than 1.2 M ☉ . Using these criteria, we identify V1721 Aql, DE Cir, CP Cru, KT Eri, V838 Her, V2672 Oph, V4160 Sgr, V4643 Sgr, V4739 Sgr, and V477 Sct as strong RN candidates. We evaluate the RN fraction among the known CNe using three methods to get 24% ± 4%, 12% ± 3%, and 35% ± 3%. With roughly a quarter of the 394 known Galactic novae actually being RNe, there should be approximately a hundred such systems masquerading as CNe.

Interprocessor interface for data transfer between PDP-8/L and NOVA 1220 dedicated gamma energy analysis systems

International Nuclear Information System (INIS)

Troyer, G.L.

1975-08-01

A method for data communication between PDP-8/L and NOVA 1220 computer-based multichannel analyzer systems is described. The method is implemented by modification of each system's operating program with appropriate I/O subroutines and by installation of a minor amount of hardware logic to a NOVA general purpose interface board. The method provides for high speed transfer of gamma energy analysis data between a Nuclear Data Corporation 50/50 system and a Tracor-Northern Corporation 660 system

Laser program annual report, 1979

Energy Technology Data Exchange (ETDEWEB)

Coleman, L.W.; Strack, J.R. (eds.)

1980-03-01

This volume provides a program overview, presenting highlights of the technical accomplishments of the elements of the program, as well as discussions of program resources and facilities. Also covered are the work of the Solid-State Laser program element, which includes systems operations, Nova, and research and development activities. (MOW)

Composite polymer: Glass edge cladding for laser disks

Science.gov (United States)

Powell, H.T.; Wolfe, C.A.; Campbell, J.H.; Murray, J.E.; Riley, M.O.; Lyon, R.E.; Jessop, E.S.

1987-11-02

Large neodymium glass laser disks for disk amplifiers such as those used in the Nova laser require an edge cladding which absorbs at 1 micrometer. This cladding prevents edge reflections from causing parasitic oscillations which would otherwise deplete the gain. Nova now utilizes volume-absorbing monolithic-glass claddings which are fused at high temperature to the disks. These perform quite well but are expensive to produce. Absorbing glass strips are adhesively bonded to the edges of polygonal disks using a bonding agent whose index of refraction matches that of both the laser and absorbing glass. Optical finishing occurs after the strips are attached. Laser disks constructed with such claddings have shown identical gain performance to the previous Nova disks and have been tested for hundreds of shots without significant degradation. 18 figs.

Composite polymer-glass edge cladding for laser disks

Science.gov (United States)

Powell, Howard T.; Riley, Michael O.; Wolfe, Charles R.; Lyon, Richard E.; Campbell, John H.; Jessop, Edward S.; Murray, James E.

1989-01-01

Large neodymium glass laser disks for disk amplifiers such as those used in the Nova laser require an edge cladding which absorbs at 1 micrometer. This cladding prevents edge reflections from causing parasitic oscillations which would otherwise deplete the gain. Nova now utilizes volume-absorbing monolithic-glass claddings which are fused at high temperature to the disks. These perform quite well but are expensive to produce. Absorbing glass strips are adhesively bonded to the edges of polygonal disks using a bonding agent whose index of refraction matches that of both the laser and absorbing glass. Optical finishing occurs after the strips are attached. Laser disks constructed with such claddings have shown identical gain performance to the previous Nova disks and have been tested for hundreds of shots without significant degradation.

Nova Scotia wind integration study : final report

International Nuclear Information System (INIS)

2008-01-01

An independent study was commissioned by the Nova Scotia Department of Energy to identify and assess the impacts of integrating large scale wind power generation into Nova Scotia's electric power system. The purpose of the study was to help Nova Scotia's efforts towards building its renewable energy supply, in order to secure a local energy resource and to protect the environment. This report provided an overview of Nova Scotia's electric power sector, including organizations involved; existing generation system; existing transmission system; renewable energy standards; Nova Scotia Power integrated resource plan; and 2007 renewable energy request for proposals. The major assumptions for the study that were discussed included system parameters; system capacity reserve requirements; expansion plans to 2020; and allocation of new wind generation by zone. Wind resource data and system dispatch modeling were also presented and transmission system modeling was outlined. This included a discussion of steady state reliability requirements; inputs to the load flow model; load flow study and contingency analysis; intra-province transmission congestion; and potential impacts on system security. The report also presented an approach to impact analysis and mitigation such as the impact on greenhouse gas and other air emissions and the impact of wind energy prices on system costs. It was concluded that one of the most important factors in evaluation of the economic impact of wind power integration is the forecasted fuel prices for the thermal units. If the fuel prices had varied significantly from the forecasted values, the study economic impact results could have been quite different. 55 tabs., 64 figs., 1 appendix

Typical examples of classical novae

Science.gov (United States)

Hack, Margherita; Selvelli, Pierluigi; Bianchini, Antonio; Duerbeck, Hilmar W.

1993-09-01

Because of the very complicated individualistic behavior of each nova, we think it necessary to review the observations of a few well-observed individuals. We have selected a few objects of different speed classes, which have been extensively observed. They are: V1500 Cygni 1975, a very fast nova; V603 Aql 1918, fast nova; CP Pup 1942, fast nova; GK Per 1901, fast nova; V 1668 Cyg 1979, moderately fast nova; FH Ser 1970, slow nova; DQ Her 1934, slow nova; T Aur 1891, slow nova; RR Pic 1925, slow nova; and HR Del 1967, very slow nova.

Nova outburst modeling and its application to the recurrent nova phenomenon

International Nuclear Information System (INIS)

Sparks, W.M.; Starrfield, S.; Truran, J.

1985-12-01

The thermonuclear runaway (TNR) theory for the cause of the common novae is reviewed. Numerical simulations of this theory were performed using an implicit hydrodynamic Lagrangian computer code. Relevant physical phenomena are explained with the simpler envelope-in-place calculations. Next the models that include accretion are discussed. The calculations agree very well with observations of common novae. The observational differences between common novae and recurrent novae are examined. We propose input parameters to the TNR model which can give the outburst characteristics of RS Ophiuchi and discuss the implications. This review is concluded with a brief discussion of two current topics in novae research: shear mixing on the white dwarf and Neon novae. 36 refs., 4 figs

The distances of the Galactic Novae

Science.gov (United States)

Ozdonmez, Aykut; Guver, Tolga; Cabrera-Lavers, Antonio; Ak, Tansel

2016-07-01

Using location of the RC stars on the CMDs obtained from the UKIDSS, VISTA and 2MASS photometry, we have derived the reddening-distance relations towards each Galactic nova for which at least one independent reddening measurement exists. We were able to determine the distances of 72 Galactic novae and set lower limits on the distances of 45 systems. The reddening curves of the systems are presented. These curves can be also used to estimate reddening or the distance of any source, whose location is close to the position of the nova in our sample. The distance measurement method in our study can be easily applicable to any source, especially for ones that concentrated along the Galactic plane.

Neural control systems for alternatively fuelled vehicles and natural gas fuel injection for DACIA NOVA

Energy Technology Data Exchange (ETDEWEB)

Sulatisky, M. [Saskatchewan Research Council, Saskatoon, SK (Canada); Ghelesel, A. [BC Gas International, Vancouver, BC (Canada)

1999-07-01

The elements of natural gas vehicle conversion technology are described as background to a discussion of the development of bi-fuel injection system for the Rumanian-manufactured DACIA-NOVA automobile. The bi-fuel injection system mirrors the fueling system installed by the original equipment manufacturer; it can also be easily installed on Ford, General Motors and DaimlerChrysler vehicles as well as on most imports.To meet emission standards after 2000, it is envisaged to install on the DACIA NOVA a neural control system (NCS) and a completely adaptive linear control system (ACLS). Details of natural gas vehicles development and the development of NCS and ACLS are discussed, including short-term and long-term objectives.

Relationship of classical novae to other eruptive variables

International Nuclear Information System (INIS)

Vogt, N.

1989-01-01

Classical novae are characterized by their well known large-amplitude outbursts, accompanied by the ejection of a shell. The same stars, however, apparently pass through much longer quiescent phases whose duration exceeds that of the outburst phase by a factor ∼ 10 5 and that of historical nova records by a factor 10 2 -10 3 . Therefore a large number of variable stars should exist which actually are classical nova systems but whose last outbursts occurred in prehistoric times. We assume that some of these stars are hidden among the so-called 'nova-lies' in the literature. However some eruptive variables and symbiotic stars, i.e. stars which certainly are not nova remnants, are mentioned. Variables related to classical novae can be divided into three main classes: (i) Potential novae which are possibly classical novae in their quiescent state. Potential novae must share the basic configuration and parameters (orbital period, masses) with classical novae; they must be semi-detached cataclysmic binaries with a white dwarf as primary and a Roche-lobe-filling red dwarf on, or near, the mainsequence as secondary. (ii) Stars which share some outburst characteristics with classical novae without having the same binary configuration. For example recurrent novae with giant secondaries, very slow novae (and symbiotic binary stars). (iii) Stars which are evolutionarily related to classical novae, i.e. which possibly are progenitors or successors of novae in their secular evolution, such as binary nuclei of planetary nebulae and close, but detached, white dwarf-red dwarf pairs (e.g. V 471 Tau), both resulting from common-envelope evolution. These three main groups of nova-related stars are discussed. (author)

Micron-scale resolution radiography of laser-accelerated and laser-exploded foils using an yttrium x-ray laser

International Nuclear Information System (INIS)

Cauble, R.; Da Silva, L.B.; Barbee, T.W. Jr.; Celliers, P.; Moreno, J.C.; Mrowka, S.; Perry, T.S.; Wan, A.S.

1994-09-01

The authors have imaged laser-accelerated foils and exploding foils on the few-micron scale using an yttrium x-ray laser (155 angstrom, 80 eV, ∼200 ps duration) and a multilayer mirror imaging system. At the maximum magnification of 30, resolution was of order one micron. The images were side-on radiographs of the foils. Accelerated foils showed significant filamentation on the rear-side (away from the driving laser) of the foil, although the laser beam was smoothed. In addition to the narrow rear-side filamentation, some shots revealed larger-scale plume-like structures on the front (driven) side of the Al foil. These plumes seem to be little-affected by beam smoothing and are likely a consequence of Rayleigh-Taylor instability. The experiments were carried out at the Nova two-beam facility

Computer program compatible with a laser nephelometer

Science.gov (United States)

Paroskie, R. M.; Blau, H. H., Jr.; Blinn, J. C., III

1975-01-01

The laser nephelometer data system was updated to provide magnetic tape recording of data, and real time or near real time processing of data to provide particle size distribution and liquid water content. Digital circuits were provided to interface the laser nephelometer to a Data General Nova 1200 minicomputer. Communications are via a teletypewriter. A dual Linc Magnetic Tape System is used for program storage and data recording. Operational programs utilize the Data General Real-Time Operating System (RTOS) and the ERT AIRMAP Real-Time Operating System (ARTS). The programs provide for acquiring data from the laser nephelometer, acquiring data from auxiliary sources, keeping time, performing real time calculations, recording data and communicating with the teletypewriter.

Classical and Recurrent Novae as Quintessential Panchromatic Transients

Science.gov (United States)

Mukai, K.; Nelson, T.; Chomiuk, L.; Finzell, T.; Linford, J.; Mioduszewski, A.; Rupen, M.; Sokoloski, J.; Weston, J.

2014-07-01

In classical and recurrent novae, thermonuclear runaway (TNR) of accreted material on the white dwarf surface results in ejection of 10^{-6} to 10^{-4} solar masses at velocities of order 1000 km s^{-1}. They are routinely detected as transients from X-rays to radio, and 6 novae (so far) have also been detected in GeV gamma-rays with Fermi/LAT. It appears that all the nearby novae are detected with Fermi, suggesting gamma-ray emission to be a universal property of novae, while a few exceptional novae further away are also detected, indicating that the gamma-ray luminosity of novae varies from system to system. Here we present selected results from our multi-wavelength observations of recent classical and recurrent novae and discuss evidence for multiple, discrete mass ejection episodes driven by a single TNR. The collision among these shells create shocks that can be observed through synchrotron radio emission and optically thin, thermal, hard X-ray emission. We do not find obvious correlation between the X-ray flux and the GeV flux, even though the latter must also result from shocks. It is clear that shocks can either be efficient particle accelerator or efficient thermal X-ray emitter, but not necessarily both at the same time.

Diagnostics of Shiva Nova produced high yield thermonuclear events

International Nuclear Information System (INIS)

Ahlstrom, H.G.; Banner, D.L.; Boyle, M.J.; Campbell, E.M.; Coleman, L.W.; Koppel, L.N.; Kornblum, H.N. Jr.; Rienecker, F.; Severyn, J.R.; Slivinsky, V.W.

1978-01-01

Experiments with the Shiva Nova laser facility which produce yield levels of scientific breakeven and above will result in neutron, x-ray and particle fluxes which will require specific attention to the survivability of diagnostic instrumentation. These yield levels will also allow the utilization of new diagnotics techniques which can provide detailed information on the state of the imploded fuel and pusher shells

An x-ray technique for precision laser beam synchronization

International Nuclear Information System (INIS)

Landen, O.L.; Lerche, R.A.; Hay, R.G.; Hammel, B.A.; Kalantar, D.; Cable, M.D.

1994-01-01

A new x-ray technique for recording the relative arrival times of multiple laser beams at a common target with better than ± 10 ps accuracy has been implemented at the Nova laser facility. 100 ps, 3ω Nova beam are focused to separate locations on a gold ribbon target viewed from the side. The measurement consists of using well characterized re-entrant x-ray streak cameras for 1-dimensional streaked imaging of the > 3 keV x-rays emanating from these isolated laser plasmas. After making the necessary correction for the differential laser, x-ray and electron transit times involved, timing offsets as low as ± 7 ps are resolved, and on subsequent shots, corrected for, verified and independently checked. This level of synchronization proved critical in meeting the power balance requirements for indirectly-driven pulse-shaped Nova implosions

Equation of State measurements of hydrogen isotopes on Nova

Energy Technology Data Exchange (ETDEWEB)

Collins, G. W., LLNL

1997-11-01

High intensity lasers can be used to perform measurements of materials at extremely high pressures if certain experimental issues can be overcome. We have addressed those issues and used the Nova laser to shock-compress liquid deuterium and obtain measurements of density and pressure on the principal Hugoniot at pressures from 300 kbar to more than 2 Mbar. The data are compared with a number of equation of state models. The data indicate that the effect of molecular dissociation of the deuterium into a monatomic phase may have a significant impact on the equation of state near 1 Mbar.

NOVA Corporation of Alberta annual report, 1992

International Nuclear Information System (INIS)

1993-01-01

Nova Corporation and its related businesses are involved in natural gas production, gas pipelines, consulting services, and upgrading of natural gas into chemicals and plastics. Nova owns Alberta Gas Transmission Division, the primary gas transportation system in Alberta, with 11,400 miles of pipeline and total deliveries in 1992 of 3.4 trillion ft 3 . Nova also owns 50% of Foothills Pipe Lines Ltd., one of Canada's largest carriers of exported gas, and 50% of TQM Pipeline Partnership, which transports natural gas in Quebec. Nova conducts its chemicals business through Novacor Chemicals Ltd., which has plants in Alberta, Ontario, Quebec, and the USA. Novacor's major petrochemicals are methanol, ethylene, propylene, and styrene and its major plastics are polystyrene, polypropylene, and polyethylene. Nova's gas-producing branch Novalta Resources produced 26 billion ft 3 of natural gas in 1992 and has proven reserves of 334 billion ft 3 . Nova's net income in 1992 was $164 million, compared to only $46 million in 1991. The company's operations, along with management discussion and analysis, are presented for 1992 and financial statements are included. 20 figs., 43 tabs

Three-dimensional simulations of Nova capsule implosion experiments

International Nuclear Information System (INIS)

Marinak, M.M.; Tipton, R.E.; Landen, O.L.

1995-01-01

Capsule implosion experiments carried out on the Nova laser are simulated with the three-dimensional HYDRA radiation hydrodynamics code. Simulations of ordered near single mode perturbations indicate that structures which evolve into round spikes can penetrate farthest into the hot spot. Bubble-shaped perturbations can burn through the capsule shell fastest, however, causing even more damage. Simulations of a capsule with multimode perturbations shows spike amplitudes evolving in good agreement with a saturation model during the deceleration phase. The presence of sizable low mode asymmetry, caused either by drive asymmetry or perturbations in the capsule shell, can dramatically affect the manner in which spikes approach the center of the hot spot. Three-dimensional coupling between the low mode shell perturbations intrinsic to Nova capsules and the drive asymmetry brings the simulated yields into closer agreement with the experimental values

OGLE ATLAS OF CLASSICAL NOVAE. II. MAGELLANIC CLOUDS

Energy Technology Data Exchange (ETDEWEB)

Mróz, P.; Udalski, A.; Poleski, R.; Soszyński, I.; Szymański, M. K.; Pietrzyński, G.; Wyrzykowski, Ł.; Ulaczyk, K.; Kozłowski, S.; Pietrukowicz, P.; Skowron, J., E-mail: pmroz@astrouw.edu.pl [Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa (Poland)

2016-01-15

The population of classical novae in the Magellanic Clouds was poorly known because of a lack of systematic studies. There were some suggestions that nova rates per unit mass in the Magellanic Clouds were higher than in any other galaxy. Here, we present an analysis of data collected over 16 years by the OGLE survey with the aim of characterizing the nova population in the Clouds. We found 20 eruptions of novae, half of which are new discoveries. We robustly measure nova rates of 2.4 ± 0.8 yr{sup −1} (LMC) and 0.9 ± 0.4 yr{sup −1} (SMC) and confirm that the K-band luminosity-specific nova rates in both Clouds are 2–3 times higher than in other galaxies. This can be explained by the star formation history in the Magellanic Clouds, specifically the re-ignition of the star formation rate a few Gyr ago. We also present the discovery of the intriguing system OGLE-MBR133.25.1160, which mimics recurrent nova eruptions.

Nova Scotia Power : in-stream tidal

International Nuclear Information System (INIS)

Meade, K.

2007-01-01

The Government of Nova Scotia, the Government of New Brunswick, Nova Scotia Power and others have funded a feasibility study of North American sites for commercial instream tidal power. In July 2007, Nova Scotia Power received partial funding for a demonstration project. This presentation provided information on a demonstration plant for tidal power run by Nova Scotia Power. It discussed the benefits of the Open Hydro technology for this plant. In this simple design, the generator is on the circumference of the turbine. The design does not involve any power transmission systems or any pitching of blades. In addition, the technology is environmentally sound as it is completely shrouded, has low rotational speed, and a large open centre allows fish to pass through, and it does not require lubricants. The last benefit that was presented was the scale up of 250 kW machine deployed in a European test facility. The presentation also discussed the advantages of developing tidal power at this time. It was concluded that tidal energy has significant potential. Although it is intermittent, it is predictable and bulk power system can be scheduled to accommodate it. figs

An estimate of the system parameters in the dwarf nova IP Peg

International Nuclear Information System (INIS)

Wood, Janet; Crawford, C.S.

1986-01-01

High-speed photometry of the eclipsing dwarf nova IP Peg is used to estimate the geometry of the binary system and the masses of its components. A white dwarf eclipse width between 0.0863 and 0.0918, is found and hence constraints on the mass ratio, q, of 0.35#lt#q#lt#0.49 and on the inclination, i, of 80 0 .9#lt#i#lt#90 0 . The white dwarf is surrounded by an extended boundary layer and has a mass of at least Msub(WD) approx.0.3 solar mass, probably much greater, depending on the thickness of the boundary layer and the orbital inclination. Its mass could be as high as 0.9 solar mass for an inclination of 80 0 .9. The mass of the secondary star is greater than 0.09 solar mass probably a lot higher. IP Peg could be earlier in the evolutionary sequence of dwarf novae than the ultra-short-period system (P#lt#2hr). (author)

Neon novae, recurrent novae, and type I supernovae

International Nuclear Information System (INIS)

Starrfield, S.; Sparks, W.M.; Truran, J.W.; Shaviv, G.; Illinois Univ., Urbana, IL; Technion-Israel Inst. of Tech., Haifa

1989-01-01

Over the past few years, we have been investigating the effects of accretion onto massive white dwarfs and its implications for their growth in mass toward the Chandrasekhar limit, in attempts to identify a possible relationship between SN I and novae. In our studies we have considered accretion at various mass accretion rates onto a variety of different white dwarf masses. We have found that there is a critical white dwarf mass above which a significant fraction of the accreted mass can remain on the white dwarf after the outburst. Below this value of the white dwarf mass, all of the accreted mass, plus core material dredged up into the envelope, is ejected as a result of the explosion. Our latest results include accretion and boundary layer heating produced by the infalling material. From these studies, we have identified some members of the class of recurrent novae, those involving a thermonuclear runaway, as the novae that are occurring on very massive white dwarfs and evolving toward an SN I explosion. One of the outgrowths of our uv studies of novae in outburst has been the identification of a class of novae which eject material that is very rich in the elements from oxygen to aluminum. We have shown that these outbursts occur on ONeMg white dwarfs, which are necessarily very massive white dwarfs. 11 refs

Shiva and Nova: progress of laser fusion at Lawrence Livermore Laboratory

International Nuclear Information System (INIS)

Ahlstrom, H.G.

1979-01-01

Over the last several years we have made significant progress in the understanding of the laser plasma interaction through the use of new diagnostic instrumentation and techniques. We have also implemented the Shiva system and operated the world's most complex laser system and produced significant target data. In the implosion experiments with the Shiva system, we have archieved densities greater than 100 x liquid density of DT. The significance of this result is that we have had to overcome the questions of achieving a spherically symmetric implosion and obviating the problem of Rayleigh-Taylor instability. We see no major obstacle in the future to attaining the densities appropriate to efficient burn of microfusion pellets for application to fusion reactors. Further, we have identified a laser system which may provide the architecture required for a fusion reactor driver and we have an agressive on going program to investigate this option for a fusion reactor driver. In addition, our Systems Studies Program has identified a reactor configuration which solves many of the important problems associated with laser fusion reactors. This is not to say that a question of the configuration of an inertial confinement fusion reactor has been settled but rather that there is a very attractive possibility and one which can be used to judge other possibilities and grade them with respect to their performance compared to the Hylife reaction chamber. Thus we hold great hope for the possibility of inertial confinement fusion as an eventual energy source to provide energy for the world

Damage resistant optics for a mega-joule solid-state laser

International Nuclear Information System (INIS)

Campbell, J.H.; Rainer, F.; Kozlowski, M.; Wolfe, C.R.; Thomas, I.; Milanovich, F.

1990-01-01

Research on Inertial Confinement Fusion (ICF) has progressed rapidly in the past several years. As a consequence, LLNL is developing plans to upgrade the current 120 kJ solid state (Nd +3 -phosphate glass) Nova laser to a 1.5 to 2 megajoule system with the goal of achieving fusion ignition. The design of the planned Nova Upgrade is briefly discussed. Because of recent improvements in the damage resistance of optical materials it is now technically and economically feasible to build a megajoule-class solid state laser. Specifically, the damage threshold of Nd +3 -doped phosphate laser glass, multilayer dielectric coatings, and non-linear optical crystals (e.g., KDP) have been dramatically improved. These materials now meet the fluence requirements for a 1.5--2 MJ Nd 3+ -glass laser operating at 1054 and 351 nm and at a pulse length of 3 ns. The recent improvements in damage thresholds are reviewed; threshold data at both 1064 and 355 nm and the measured pulse length scaling are presented. 20 refs., 9 figs., 2 tabs

A statistical analysis of IUE spectra of dwarf novae and nova-like stars

Science.gov (United States)

Ladous, Constanze

1990-01-01

First results of a statistical analysis of the IUE International Ultraviolet Explorer archive on dwarf novae and nova like stars are presented. The archive contains approximately 2000 low resolution spectra of somewhat over 100 dwarf novae and nova like stars. Many of these were looked at individually, but so far the collective information content of this set of data has not been explored. The first results of work are reported.

Development and characterization of a CCD camera system for use on six-inch manipulator systems

International Nuclear Information System (INIS)

Logory, L.M.; Bell, P.M.; Conder, A.D.; Lee, F.D.

1996-01-01

The Lawrence Livermore National Laboratory has designed, constructed, and fielded a compact CCD camera system for use on the Six Inch Manipulator (SIM) at the Nova laser facility. The camera system has been designed to directly replace the 35 mm film packages on all active SIM-based diagnostics. The unit's electronic package is constructed for small size and high thermal conductivity using proprietary printed circuit board technology, thus reducing the size of the overall camera and improving its performance when operated within the vacuum environment of the Nova laser target chamber. The camera has been calibrated and found to yield a linear response, with superior dynamic range and signal-to-noise levels as compared to T-Max 3200 optic film, while providing real-time access to the data. Limiting factors related to fielding such devices on Nova will be discussed, in addition to planned improvements of the current design

CIRCUMSTELLAR SHELL FORMATION IN SYMBIOTIC RECURRENT NOVAE

Energy Technology Data Exchange (ETDEWEB)

Moore, Kevin; Bildsten, Lars [Department of Physics, Broida Hall, University of California, Santa Barbara, CA 93106 (United States)

2012-12-20

We present models of spherically symmetric recurrent nova shells interacting with circumstellar material (CSM) in a symbiotic system composed of a red giant (RG) expelling a wind and a white dwarf accreting from this material. Recurrent nova eruptions periodically eject material at high velocities ({approx}> 10{sup 3} km s{sup -1}) into the RG wind profile, creating a decelerating shock wave as CSM is swept up. High CSM densities cause the shocked wind and ejecta to have very short cooling times of days to weeks. Thus, the late-time evolution of the shell is determined by momentum conservation instead of energy conservation. We compute and show evolutionary tracks of shell deceleration, as well as post-shock structure. After sweeping up all the RG wind, the shell coasts at a velocity {approx}100 km s{sup -1}, depending on system parameters. These velocities are similar to those measured in blueshifted CSM from the symbiotic nova RS Oph, as well as a few Type Ia supernovae that show evidence of CSM, such as 2006X, 2007le, and PTF 11kx. Supernovae occurring in such systems may not show CSM interaction until the inner nova shell gets hit by the supernova ejecta, days to months after the explosion.

A nova outburst powered by shocks

Science.gov (United States)

Li, Kwan-Lok; Metzger, Brian D.; Chomiuk, Laura; Vurm, Indrek; Strader, Jay; Finzell, Thomas; Beloborodov, Andrei M.; Nelson, Thomas; Shappee, Benjamin J.; Kochanek, Christopher S.; Prieto, José L.; Kafka, Stella; Holoien, Thomas W.-S.; Thompson, Todd A.; Luckas, Paul J.; Itoh, Hiroshi

2017-10-01

Classical novae are runaway thermonuclear burning events on the surfaces of accreting white dwarfs in close binary star systems, sometimes appearing as new naked-eye sources in the night sky1. The standard model of novae predicts that their optical luminosity derives from energy released near the hot white dwarf, which is reprocessed through the ejected material2-5. Recent studies using the Fermi Large Area Telescope have shown that many classical novae are accompanied by gigaelectronvolt γ-ray emission6,7. This emission likely originates from strong shocks, providing new insights into the properties of nova outflows and allowing them to be used as laboratories for the study of the unknown efficiency of particle acceleration in shocks. Here, we report γ-ray and optical observations of the Milky Way nova ASASSN-16ma, which is among the brightest novae ever detected in γ-rays. The γ-ray and optical light curves show a remarkable correlation, implying that the majority of the optical light comes from reprocessed emission from shocks rather than the white dwarf8. The ratio of γ-ray to optical flux in ASASSN-16ma directly constrains the acceleration efficiency of non-thermal particles to be around 0.005, favouring hadronic models for the γ-ray emission9. The need to accelerate particles up to energies exceeding 100 gigaelectronvolts provides compelling evidence for magnetic field amplification in the shocks.

Radiation of dwarf novae

International Nuclear Information System (INIS)

Bruch, A.

1987-01-01

The nature of dwarf novae with their components white dwarf star, cool star, accretion disk, boundary layer and hot spot is investigated. It is shown that very different physical states and processes occur in the components of dwarf novae. Spectroscopical and photometrical observations are carried out. For better understanding the radiation portions of the single dwarf novae components are separated from the total electromagnetic spectrum recieved from the dwarf novae. The model assumptions are compared with the observations and verified

A Hubble Space Telescope Survey for Novae in M87. II. Snuffing out the Maximum Magnitude–Rate of Decline Relation for Novae as a Non-standard Candle, and a Prediction of the Existence of Ultrafast Novae

Energy Technology Data Exchange (ETDEWEB)

Shara, Michael M.; Doyle, Trisha; Zurek, David [Department of Astrophysics, American Museum of Natural History, Central Park West and 79th Street, New York, NY 10024-5192 (United States); Lauer, Tod R. [National Optical Astronomy Observatory, P.O. Box 26732, Tucson, AZ 85726 (United States); Baltz, Edward A. [KIPAC, SLAC, 2575 Sand Hill Road, M/S 29, Menlo Park, CA 94025 (United States); Kovetz, Attay [School of Physics and Astronomy, Faculty of Exact Sciences, Tel Aviv University, Tel Aviv (Israel); Madrid, Juan P. [CSIRO, Astronomy and Space Science, P.O. Box 76, Epping, NSW 1710 (Australia); Mikołajewska, Joanna [N. Copernicus Astronomical Center, Polish Academy of Sciences, Bartycka 18, PL 00-716 Warsaw (Poland); Neill, J. D. [California Institute of Technology, 1200 East California Boulevard, MC 278-17, Pasadena CA 91125 (United States); Prialnik, Dina [Department of Geosciences, Tel Aviv University, Ramat Aviv, Tel Aviv 69978 (Israel); Welch, D. L. [Department of Physics and Astronomy, McMaster University, Hamilton, L8S 4M1, Ontario (Canada); Yaron, Ofer [Department of Particle Physics and Astrophysics, Weizmann Institute of Science, 76100 Rehovot (Israel)

2017-04-20

The extensive grid of numerical simulations of nova eruptions from the work of Yaron et al. first predicted that some classical novae might significantly deviate from the Maximum Magnitude–Rate of Decline (MMRD) relation, which purports to characterize novae as standard candles. Kasliwal et al. have announced the observational detection of a new class of faint, fast classical novae in the Andromeda galaxy. These objects deviate strongly from the MMRD relationship, as predicted by Yaron et al. Recently, Shara et al. reported the first detections of faint, fast novae in M87. These previously overlooked objects are as common in the giant elliptical galaxy M87 as they are in the giant spiral M31; they comprise about 40% of all classical nova eruptions and greatly increase the observational scatter in the MMRD relation. We use the extensive grid of the nova simulations of Yaron et al. to identify the underlying causes of the existence of faint, fast novae. These are systems that have accreted, and can thus eject, only very low-mass envelopes, of the order of 10{sup −7}–10{sup −8} M {sub ⊙}, on massive white dwarfs. Such binaries include, but are not limited to, the recurrent novae. These same models predict the existence of ultrafast novae that display decline times, t {sub 2,} to be as short as five hours. We outline a strategy for their future detection.

Can isolated single black holes produce X-ray novae?

Science.gov (United States)

Matsumoto, Tatsuya; Teraki, Yuto; Ioka, Kunihito

2018-03-01

Almost all black holes (BHs) and BH candidates in our Galaxy have been discovered as soft X-ray transients, so-called X-ray novae. X-ray novae are usually considered to arise from binary systems. Here, we propose that X-ray novae are also caused by isolated single BHs. We calculate the distribution of the accretion rate from interstellar matter to isolated BHs, and find that BHs in molecular clouds satisfy the condition of the hydrogen-ionization disc instability, which results in X-ray novae. The estimated event rate is consistent with the observed one. We also check an X-ray novae catalogue (Corral-Santana et al.) and find that 16/59 ˜ 0.27 of the observed X-ray novae are potentially powered by isolated BHs. The possible candidates include IGR J17454-2919, XTE J1908-094, and SAX J1711.6-3808. Near-infrared photometric and spectroscopic follow-ups can exclude companion stars for a BH census in our Galaxy.

Long-Term Photometry of Very Slow Novae

Directory of Open Access Journals (Sweden)

Chochol D.

2003-12-01

Full Text Available Long-term photographic, photoelectric and recent CCD photometry of the classical nova V723 Cas and symbiotic novae V1329 Cyg, PU Vul, V1016 Cyg and HM Sge were used to find their orbital periods. The arguments in favor of the presence of the third components in these systems are given. Physical processes, responsible for the brightness variations, are discussed.

Spectral evolution of Nova V400 Per (1974) and Nova V373 Sct (1975)

International Nuclear Information System (INIS)

Rosino, L.

1978-01-01

Photographic and spectroscopic observations of the two galactic novae, V400 Per and V373 Sct, which appeared in 1974 and 1975, have been carried out at Asiago. The light curves of the two novae were characterized by the presence of brightness oscillations during the early decline. The spectral evolution was quite normal: the spectra showed at first, over a relatively strong continuum, wide emission bands of moderate excitation, accompanied by blueshifted absorptions, with radial velocities of - 1760 kms -1 (Nova Per) and - 1260 kms -1 (Nova Sct). Later, after the novae entered the nebular stage, the continuum weakened, the absorption disappeared and the novae displayed the usual emission spectrum, with permitted and forbidden lines of high excitation ([O III], N III, He I, He II). Forbidden lines of Fe VI and Fe VII - and in Nova Sct, also Fe X and A X - were present for a time, but they soon disappeared, so that at the end the spectrum was dominated by the [O III] nebular lines, even stronger than Hα. (Auth.)

A flickering study of nova-like systems KR Aur and UU Aqr

Science.gov (United States)

Dobrotka, A.; Mineshige, S.; Casares, J.

2012-03-01

We present a study of the flickering activity in two nova-like systems, KR Aur and UU Aqr. We applied a statistical model of flickering simulations in accretion discs based on turbulent angular momentum transport between two adjacent rings with an exponential distribution of the turbulence dimension scale. The model is based on a steady-state disc model, which is satisfied in the case of hot ionized discs of nova-like cataclysmic variables. Our model successfully fits the observed power-density spectrum of KR Aur with the disc parameter α= 0.10-0.40 and an inner-disc truncation radius in the range Rin= 0.88-1.67 × 109 cm. The exact values depend on the mass-transfer rate in the sense that α decreases and Rin increases with mass-transfer rate. In any case, the inner-disc radius found for KR Aur is considerably smaller than those for quiescent dwarf novae, as predicted by the disc instability model. On the other hand, our simulations fail to reproduce the power-density spectrum of UU Aqr. A tantalizing explanation involves the possible presence of spiral waves, which are expected in UU Aqr because of its low mass ratio but not in KR Aur. In general our model predicts the observed concentration of flickering in the central disc. We explain this by the radial dependence of the angular-momentum gradient.

Laser targets: introduction

International Nuclear Information System (INIS)

Rosen, M.D.

1985-01-01

The laser target design group was engaged in three main tasks in 1984: (1) analyzing Novette implosion and hohlraum-scaling data, (2) planning for the first experiments on Nova, and (3) designing laboratory x-ray laser targets and experiments. The Novette implosion and hohlraum scaling data are mostly classified and are therefore not discussed in detail here. The authors achieved average final/initial pusher pr ratios of about 50, some 3 times higher than the value achieved in the best Shiva shots. These pr values imply a fuel compression to 100 times liquid density, although this figure and other aspects of the experiments are subject to further interpretation because of detailed questions of target symmetry and stability. Their main long-term goal for Nova is to produce a so-called hydrodynamically equivalent target (HET) - that is, a target whose hydrodynamic behavior (implosion velocity, convergence ratio, symmetry and stability requirements, etc.) is very much like that of a high-gain target, but one that is scaled down in size to match the energy available from Nova and is too small to achieve enough hot-spot pr to ignite the cold, near-Fermi-degenerate fuel around it. Their goal for Nova's first year is to do experiments that will teach them how to achieve the symmetry and stability conditions required by an HET

Laser program overview

International Nuclear Information System (INIS)

Storm, E.; Coleman, L.W.

1985-01-01

The objectives of the Lawrence Livermore National Laboratory Laser Fusion program are to understand and develop the science and technology of inertial confinement fusion (ICF), and to utilize ICF in short- and long-term military applications, and, in the long-term, as a candidate for central-station civilian power generation. In 1984, using the Novette laser system, the authors completed experiments showing the very favorable scaling of laser-plama interactions with short-wavelength laser light. Their Novette experiments have unequivocally shown that short laser wavelength, i.e., less than 1 μm, is required to provide the drive necessary for efficient compression, ignition, and burn of DT fusion fuel. In other experiments with Novette, the authors made the first unambiguous observation of amplified spontaneous emission in the soft x-ray regime. The authors also conducted military applications and weapons physics experiments, which they discuss in detail in the classified volume of our Laser Program Annual Report. In the second thrust, advanced laser studies, they develop and test the concepts, components, and materials for present and future laser systems. Over the years, this has meant providing the technology base and scientific advances necessary to construct and operate a succession of six evermore-powerful laser systems. The latest of these, Nova, a 100-TW/100-kJ-class laser system, was completed in 1984. The Nd:glass laser continues to be the most effective and versatile tool for ICF and weapons physics because of its scalability in energy, the ability to efficiently convert its 1=μm output to shorter wavelengths, its ability to provide flexible, controlled pulse shaping, and its capability to adapt to a variety of irradiation and focusing geometries. For these reasons, many of our advanced laser studies are in areas appropriate to solid state laser technologies

THE DUSTY NOVA V1065 CENTAURI (NOVA CEN 2007): A SPECTROSCOPIC ANALYSIS OF ABUNDANCES AND DUST PROPERTIES

International Nuclear Information System (INIS)

Helton, L. Andrew; Woodward, Charles E.; Gehrz, Robert D.; Walter, Frederick M.; Vanlandingham, Karen; Schwarz, Greg J.; Evans, Aneurin; Ness, Jan-Uwe; Geballe, Thomas R.; Greenhouse, Matthew; Krautter, Joachim; Liller, William; Lynch, David K.; Rudy, Richard J.; Shore, Steven N.; Starrfield, Sumner; Truran, Jim

2010-01-01

We examine the ejecta evolution of the classical nova V1065 Centauri, constructing a detailed picture of the system based on spectrophotometric observations obtained from 9 to approximately 900 days post-outburst with extensive coverage from optical to mid-infrared wavelengths. We estimate a reddening toward the system of E(B-V) = 0.5 ± 0.1, based upon the B - V color and analysis of the Balmer decrement, and derive a distance estimate of 8.7 +2.8 -2.1 kpc. The optical spectral evolution is classified as P o fe N ne A o according to the CTIO Nova Classification system of Williams et al. Photoionization modeling yields absolute abundance values by number, relative to solar of He/H = 1.6 ± 0.3, N/H = 144 ± 34, O/H = 58 ± 18, and Ne/H = 316 ± 58 for the ejecta. We derive an ejected gas mass of M g = (1.6 ± 0.2) x 10 -4 M sun . The infrared excess at late epochs in the evolution of the nova arises from dust condensed in the ejecta composed primarily of silicate grains. We estimate a total dust mass, M d , of order (0.2-3.7) x 10 -7 M sun , inferred from modeling the spectral energy distribution observed with the Spitzer IRS and Gemini-South GNIRS spectrometers. Based on the speed class, neon abundance, and the predominance of silicate dust, we classify V1065 Cen as an ONe-type classical nova.

SWSex Stars, Old Novae, and the Evolution of Cataclysmic Variables

Directory of Open Access Journals (Sweden)

L. Schmidtobreick

2015-02-01

Full Text Available The population of cataclysmic variables with orbital periods right above the period gap are dominated by systems with extremely high mass transfer rates, the so-called SW Sextantis stars. On the other hand, some old novae in this period range which are expected to show high mass transfer rate instead show photometric and/or spectroscopic resemblance to low mass transfer systems like dwarf novae. We discuss them as candidates for so-called hibernating systems, CVs that changed their mass transfer behaviour due to a previously experienced nova outburst. This paper is designed to provide input for further research and discussion as the results as such are still very preliminary.

1981 laser program annual report

Energy Technology Data Exchange (ETDEWEB)

1982-08-01

This report is published in sections that correspond to the division of technical activity in the Program. Section 1 provides a Program Overview, presenting highlights of the technical accomplishments of the elements of the Program, a summary of activities carried out under the Glass Laser Experiments Lead Laboratory Program, as well as discussions of Program resources and facilities. Section 2 covers the work on solid-state Nd:glass lasers, including systems operations and Nova and Novette systems development. Section 3 reports on target-design activities, plasma theory and simulation, code development, and atomic theory. Section 4 presents the accomplishments of the Target Fabrication group, Section 5 contains the results of our diagnostics development, and Section 6 reports the results of laser-target experiments conducted during the year, along with supporting research and development activities. Section 7 presents the results from laser research and development, including solid-state R and D and the theoretical and experimental research on advanced lasers. Section 8 contains the results of studies in areas of energy and military applications, including those relating to electrical energy production by inertial-confinement fusion systems.

1981 laser program annual report

International Nuclear Information System (INIS)

1982-08-01

This report is published in sections that correspond to the division of technical activity in the Program. Section 1 provides a Program Overview, presenting highlights of the technical accomplishments of the elements of the Program, a summary of activities carried out under the Glass Laser Experiments Lead Laboratory Program, as well as discussions of Program resources and facilities. Section 2 covers the work on solid-state Nd:glass lasers, including systems operations and Nova and Novette systems development. Section 3 reports on target-design activities, plasma theory and simulation, code development, and atomic theory. Section 4 presents the accomplishments of the Target Fabrication group, Section 5 contains the results of our diagnostics development, and Section 6 reports the results of laser-target experiments conducted during the year, along with supporting research and development activities. Section 7 presents the results from laser research and development, including solid-state R and D and the theoretical and experimental research on advanced lasers. Section 8 contains the results of studies in areas of energy and military applications, including those relating to electrical energy production by inertial-confinement fusion systems

Nova Aql 1918: A nude old nova

International Nuclear Information System (INIS)

Selvelli, P.L.; Cassatella, A.

1981-01-01

IUE observations at high and low resolution of Nova Aql 1918 show neither evidence of outflow nor the presence of nebular lines. This indicates that the shell ejected at the time of the outburst and surrounding the system for many years (Mustel and Boyarchuck, 1970) has by now disappeared. The high excitation spectrum presents rapid variations in the far UV and eclipse effects in the near UV that seem well correlated with the orbital phase. The observations can be interpreted in terms of phenomena occurring in or near the accretion disk surrounding the white dwarf. However, the small inclination of the orbital axis raises serious problems in trying to model the system. (Auth.)

PHOTOMETRIC AND SPECTROSCOPIC PROPERTIES OF NOVAE IN THE LARGE MAGELLANIC CLOUD

International Nuclear Information System (INIS)

Shafter, A. W.

2013-01-01

The photometric and spectroscopic properties of the 43 known LMC nova candidates are summarized and reviewed. Of these, photometric data sufficient to establish decline rates are available for 29 novae, while spectroscopic data sufficient to establish the spectroscopic classes are available for 18 systems. Half of the 18 novae belong to the Fe II class, with the remaining nine belonging to either the He/N or the Fe IIb classes. As seen in previous nova studies of M31 and M33, the He/N and Fe IIb novae have on average faster photometric developments than do their Fe II counterparts. Overall, the available photometry confirms earlier studies, and shows conclusively that LMC novae have faster rates of decline than do novae in the Galaxy and M31. It appears that the increased fraction of faster, He/N and Fe IIb novae observed in the LMC compared with M31 is almost certainly the result of differences in the underlying stellar population between the two galaxies. We propose that the younger population seen in the LMC compared with M31's bulge (where most of the novae are found), produces progenitor binaries with higher average white dwarf masses. The higher mean white dwarf mass not only produces a larger fraction of fast, He/N novae compared with M31, but also results in a relatively large recurrent nova population.

Tracking the NOvA Detectors' Performance

Science.gov (United States)

Psihas, Fernanda; NOvA Collaboration

2016-03-01

The NOvA experiment measures long baseline νμ -->νe oscillations in Fermilab's NuMI beam. We employ two detectors equipped with over 10 thousand sets of data-taking electronics; avalanche photo diodes and front end boards which collect and process the scintillation signal from particle interactions within the detectors. These sets of electronics -as well as the systems which power and cool them- must be monitored and maintained at precise working conditions to ensure maximal data-taking uptime, good data quality and a lasting life for our detectors. This poster describes the automated systems used on NOvA to simultaneously monitor our data quality, diagnose hardware issues, track our performance and coordinate maintenance for the detectors.

High-power laser source evaluation

International Nuclear Information System (INIS)

Back, C.A.; Decker, C.D.; Dipeso, G.J.; Gerassimenko, M.; Managan, R.A.; Serduke, F.J.D.; Simonson, G.F.; Suter, L.J.

1997-07-01

This document reports progress in these areas: EXPERIMENTAL RESULTS FROM NOVA: TAMPED XENON UNDERDENSE X-RAY EMITTERS; MODELING MULTI-KEV RADIATION PRODUCTION OF XENON-FILLED BERYLLIUM CANS; MAPPING A CALCULATION FROM LASNEX TO CALE; HOT X RAYS FROM SEEDED NIF CAPSULES; HOHLRAUM DEBRIS MEASUREMENTS AT NOVA; FOAM AND STRUCTURAL RESPONSE CALCULATIONS FOR NIF NEUTRON EXPOSURE SAMPLE CASE ASSEMBLY DESIGN; NON-IGNITION X-RAY SOURCE FLUENCE-AREA PRODUCTS FOR NUCLEAR EFFECTS TESTING ON NIF. Also appended are reprints of two papers. The first is on the subject of ''X-Ray Production in Laser-Heated Xe Gas Targets.'' The second is on ''Efficient Production and Applications of 2- to 10-keV X Rays by Laser-Heated Underdense Radiators.''

Uranium in Nova Scotia: a background summary for the uranium inquiry, Nova Scotia

International Nuclear Information System (INIS)

1982-01-01

Since the mid 1970's Nova Scotia has experienced increased exploration for a number of commodities including uranium. The exploration activity for uranium has resulted in discovery of significant occurrences of the element. It became obvious to the Government of Nova Scotia that a segment of the population of the Province is concerned about the potential hazards associated with the exploration, mining and milling stages of the uranium industry. Public concern has resulted in the appointment of a Commissioner under the Public Inquiries Act of Nova Scotia to inquire and make recommendations to the Governor-in-Council on all aspects of exploration, development, mining, processing, storage, waste management and transportation of uranium in any form. The regulation of mineral exploration and mining activities is carried out by the Nova Scotia Department of Mines and Energy through the Mineral Resources Act of the Province of Nova Scotia. The regulation of the special radioactive aspects involved in the mining and processing of uranium ore is the responsibility of the federal Atomic Energy Control Board. The purposes of this report is to: outline the history of uranium exploration in Nova Scotia; summarize the results of geological surveys by provincial and federal government agencies, universities and exploration companies which document the natural levels of radioactivity in the Province; briefly outline the physical and chemical characteristics of uranium and thorium which make these elements unique and a potential environmental and health concern; outline chronologically the steps taken by the Nova Scotia Department of Mines and Energy to monitor and regulate uranium exploration activities; classify the types of uranium deposits known to occur in Nova Scotia and describe their main geological features; outline the role of the Nova Scotia Department of Mines and Energy in the regulation of mining activities in the Province. The report is written for the interested

NOVANET: communications network for a control system

International Nuclear Information System (INIS)

Hill, J.R.; Severyn, J.R.; VanArsdall, P.J.

1983-01-01

NOVANET is a control system oriented fiber optic local area network that was designed to meet the unique and often conflicting requirements of the Nova laser control system which will begin operation in 1984. The computers and data acquisition devices that form the distributed control system for a large laser fusion research facility need reliable, high speed communications. Both control/status messages and experimental data must be handled. A subset of NOVANET is currently operating on the two beam Novette laser system

The NOvA Technical Design Report

International Nuclear Information System (INIS)

Ayres, D.S.; Drake, G.R.; Goodman, M.C.; Grudzinski, J.J.; Guarino, V.J.; Talaga, R.L.; Zhao, A.; Stamoulis, P.; Stiliaris, E.; Tzanakos, G.; Zois, M.

2007-01-01

Technical Design Report (TDR) describes the preliminary design of the NOvA accelerator upgrades, NOvA detectors, detector halls and detector sites. Compared to the March 2006 and November 2006 NOvA Conceptual Design Reports (CDR), critical value engineering studies have been completed and the alternatives still active in the CDR have been narrowed to achieve a preliminary technical design ready for a Critical Decision 2 review. Many aspects of NOvA described this TDR are complete to a level far beyond a preliminary design. In particular, the access road to the NOvA Far Detector site in Minnesota has an advanced technical design at a level appropriate for a Critical Decision 3a review. Several components of the accelerator upgrade and new neutrino detectors also have advanced technical designs appropriate for a Critical Decision 3a review. Chapter 1 is an Executive Summary with a short description of the NOvA project. Chapter 2 describes how the Fermilab NuMI beam will provide a narrow band beam of neutrinos for NOvA. Chapter 3 gives an updated overview of the scientific basis for the NOvA experiment, focusing on the primary goal to extend the search for ν μ → ν e oscillations and measure the sin 2 (2θ 13 ) parameter. This parameter has not been measured in any previous experiment and NOvA would extend the search by about an order of magnitude beyond the current limit. A secondary goal is to measure the dominant mode oscillation parameters, sin 2 (2θ 23 ) and Δm 32 2 to a more precise level than previous experiments. Additional physics goals for NOvA are also discussed. Chapter 4 describes the Scientific Design Criteria which the Fermilab accelerator complex, NOvA detectors and NOvA detector sites must satisfy to meet the physics goals discussed in Chapter 3. Chapter 5 is an overview of the NOvA project. The changes in the design relative to the NOvA CDR are discussed. Chapter 6 summarizes the NOvA design performance relative to the Design Criteria set out

Climate change in Nova Scotia : a background paper to guide Nova Scotia's climate change action plan

International Nuclear Information System (INIS)

2007-10-01

Climate change causes changes in the temperature of the earth, the level of the sea, and the frequency of extreme weather conditions. The province of Nova Scotia recently released an act related to environmental goals and sustainable prosperity. Addressing climate change is a key element in achieving Nova Scotia's sustainable prosperity goals outlined in the act. The Nova Scotia Department of Energy is working towards developing both policy and action, to help meet its target of a 10 per cent reduction in greenhouse gases from 1990 levels by the year 2020. Two major plans are underway, notably a climate change action plan and a renewed energy strategy. This report provided background information on Nova Scotia's climate change action plan. It discussed climate change issues affecting Nova Scotia, air pollutants, energy sources in Nova Scotia, energy consumers in the province, and Nova Scotia's approach to climate change. The report also discussed actions underway and funding sources. It was concluded that in order for the climate change action plan to be successful, Nova Scotians must use energy more efficiently; use renewable energy; use cleaner energy; and plan for change. 13 refs., 2 tabs., 6 figs., 4 appendices

Laser system using ultra-short laser pulses

Science.gov (United States)

Dantus, Marcos [Okemos, MI; Lozovoy, Vadim V [Okemos, MI; Comstock, Matthew [Milford, MI

2009-10-27

A laser system using ultrashort laser pulses is provided. In another aspect of the present invention, the system includes a laser, pulse shaper and detection device. A further aspect of the present invention employs a femtosecond laser and binary pulse shaping (BPS). Still another aspect of the present invention uses a laser beam pulse, a pulse shaper and a SHG crystal.

Laser cladding to select new glassy alloys; Uso do metodo de revestimento por laser na selecao de novas ligas vitreas

Energy Technology Data Exchange (ETDEWEB)

Medrano, L.L.O.; Afonso, C.R.M.; Kiminami, C.S.; Gargarella, P., E-mail: eomedranos@hotmail.com [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil). Departamento de Engenharia de Materiais; Vilar, R. [Instituto Superior Tecnico, Departamento de Engenharia Quimica, Lisboa (Portugal); Ramasco, B. [Whirlpool Latin America, Rio Claro, SP (Brazil)

2016-07-01

A new experimental technique used to analyze the effect of compositional variation and cooling rate in the phase formation in a multicomponent system is the laser cladding. This work have evaluated the use of laser cladding to discover a new bulk metallic glass (BMG) in the Al-Co-Zr system. Coatings with composition variation have made by laser cladding using Al-Co-Zr alloys powders and the samples produced have been characterized by X ray diffraction, microscopy and energy-dispersive X-ray spectroscopy. The results did not show the composition variation as expected, because of incomplete melting during laser process. It was measured a composition variation tendency that allowed the glass forming investigation by the glass formation criterion λ+Δh{sup 1/2}. The results have showed no glass formation in the coating samples, which prove a limited capacity of Zr-Co-Al system to form glass (author)

Flow visualizations, velocity measurements, and surface convection measurements in simulated 20.8-cm Nova box amplifier cavities

International Nuclear Information System (INIS)

Julien, J.L.; Molishever, E.L.

1983-01-01

Reported are fluid mechanics experiments performed in models of the 20.8-cm Nova amplifier lamp and disk cavities. Lamp cavity nitrogen flows are shown, by both flow visualization and velocity measurements, to be acceptably uniform and parallel to the flashlamps. In contrast, the nitrogen flows in the disk cavity are shown to be disordered. Even though disk cavity flows are disordered, the simplest of three proposed nitrogen introduction systems for the disk cavity was found to be acceptable based on convection measurements made at the surfaces of simulated laser disks

Slow magnetic monopoles search in NOvA

Science.gov (United States)

Antoshkin, Alexander; Frank, Martin

2018-04-01

The NOvA far detector is well suited for finding exotic particles due to its technical features (see [1]). One type of those exotic particles is a "slow" magnetic monopole. It is assumed that the energy deposition of such monopoles should be enough to be registered (see [2]). Measurement of the expected signals was performed on the NOvA test bench at JINR (see [3]). Result of this measurement allows us to perform slow monopole's research using NOvA software and hardware with high efficiency. As a whole, the research can lead to a discovery, or it can limit the existence of monopoles in a wide range of parameters, previously unreachable in other experiments (MACRO, SLIM, RICE, IceCube). Several special software tools have been developed. Slow Monopole Trigger has been created and implemented in the NOvA Data-Driven-Trigger system. Also, an online reconstruction algorithm has been developed and tested on 5% of the data. A technical description of these tools and current results of the analysis are presented in this work.

Robot-laser system

International Nuclear Information System (INIS)

Akeel, H.A.

1987-01-01

A robot-laser system is described for providing a laser beam at a desired location, the system comprising: a laser beam source; a robot including a plurality of movable parts including a hollow robot arm having a central axis along which the laser source directs the laser beam; at least one mirror for reflecting the laser beam from the source to the desired location, the mirror being mounted within the robot arm to move therewith and relative thereto to about a transverse axis that extends angularly to the central axis of the robot arm; and an automatic programmable control system for automatically moving the mirror about the transverse axis relative to and in synchronization with movement of the robot arm to thereby direct the laser beam to the desired location as the arm is moved

The NOvA Technical Design Report

Energy Technology Data Exchange (ETDEWEB)

Ayres, D.S.; Drake, G.R.; Goodman, M.C.; Grudzinski, J.J.; Guarino, V.J.; Talaga, R.L.; Zhao, A.; /Argonne; Stamoulis, P.; Stiliaris, E.; Tzanakos, G.; Zois, M.; /Athens U. /Caltech /UCLA /Fermilab /College de France /Harvard U. /Indiana U. /Lebedev Inst. /Michigan State U. /Minnesota U., Duluth /Minnesota U.

2007-10-08

Technical Design Report (TDR) describes the preliminary design of the NOvA accelerator upgrades, NOvA detectors, detector halls and detector sites. Compared to the March 2006 and November 2006 NOvA Conceptual Design Reports (CDR), critical value engineering studies have been completed and the alternatives still active in the CDR have been narrowed to achieve a preliminary technical design ready for a Critical Decision 2 review. Many aspects of NOvA described this TDR are complete to a level far beyond a preliminary design. In particular, the access road to the NOvA Far Detector site in Minnesota has an advanced technical design at a level appropriate for a Critical Decision 3a review. Several components of the accelerator upgrade and new neutrino detectors also have advanced technical designs appropriate for a Critical Decision 3a review. Chapter 1 is an Executive Summary with a short description of the NOvA project. Chapter 2 describes how the Fermilab NuMI beam will provide a narrow band beam of neutrinos for NOvA. Chapter 3 gives an updated overview of the scientific basis for the NOvA experiment, focusing on the primary goal to extend the search for {nu}{sub {mu}} {yields} {nu}{sub e} oscillations and measure the sin{sup 2}(2{theta}{sub 13}) parameter. This parameter has not been measured in any previous experiment and NOvA would extend the search by about an order of magnitude beyond the current limit. A secondary goal is to measure the dominant mode oscillation parameters, sin{sup 2}(2{theta}{sub 23}) and {Delta}m{sub 32}{sup 2} to a more precise level than previous experiments. Additional physics goals for NOvA are also discussed. Chapter 4 describes the Scientific Design Criteria which the Fermilab accelerator complex, NOvA detectors and NOvA detector sites must satisfy to meet the physics goals discussed in Chapter 3. Chapter 5 is an overview of the NOvA project. The changes in the design relative to the NOvA CDR are discussed. Chapter 6 summarizes the NOvA

NOvA Event Building, Buffering and Data-Driven Triggering From Within the DAQ System

Energy Technology Data Exchange (ETDEWEB)

Fischler, M. [Fermilab; Green, C. [Fermilab; Kowalkowski, J. [Fermilab; Norman, A. [Fermilab; Paterno, M. [Fermilab; Rechenmacher, R. [Fermilab

2012-06-22

To make its core measurements, the NOvA experiment needs to make real-time data-driven decisions involving beam-spill time correlation and other triggering issues. NOvA-DDT is a prototype Data-Driven Triggering system, built using the Fermilab artdaq generic DAQ/Event-building tools set. This provides the advantages of sharing online software infrastructure with other Intensity Frontier experiments, and of being able to use any offline analysis module--unchanged--as a component of the online triggering decisions. The NOvA-artdaq architecture chosen has significant advantages, including graceful degradation if the triggering decision software fails or cannot be done quickly enough for some fraction of the time-slice ``events.'' We have tested and measured the performance and overhead of NOvA-DDT using an actual Hough transform based trigger decision module taken from the NOvA offline software. The results of these tests--98 ms mean time per event on only 1/16 of th e available processing power of a node, and overheads of about 2 ms per event--provide a proof of concept: NOvA-DDT is a viable strategy for data acquisition, event building, and trigger processing at the NOvA far detector.

School Psychology in Nova Scotia

Science.gov (United States)

King, Sara; McGonnell, Melissa; Noyes, Amira

2016-01-01

Registration as a psychologist in Nova Scotia can be at the master's or doctoral level; however, the Nova Scotia Board of Examiners in Psychology has announced a move to the doctoral degree as the entry-level to practice. Many school psychologists in Nova Scotia practice at the master's level; therefore, this change could affect school psychology…

Explosive hydrogen burning in novae

International Nuclear Information System (INIS)

Wiescher, M.; Goerres, J.; Thielemann, F.K.; Ritter, H.

1986-01-01

Recent observations (nova CrA 81 and Aql 82) reported large enhancements of element abundances beyond CNO nuclei in nova ejecta, which still wait for a clear theoretical explanation. Attempts to interprete these findings include scenarios like nova events on a O-Ne-Mg white dwarf or nuclear processing which enables the transfer of CNO material to heavier nuclei. In the present study we included all available nuclear information on proton-rich unstable nuclei, to update thermo-nuclear reaction rates in explosive hydrogen burning. They are applied in a systematic analysis of explosive hydrogen burning for a variety of temperature conditions, appropriate to nova explosions. We find that (a) for temperatures T>2 10 8 K, pre-existing material in Ne, Al, or Mg can be transferred to heavier nuclei following the flow pattern of a r(apid) p(roton-capture) process (b) for T> or approx.3.5 10 8 K CNO matter can be processed to heavier nuclei (in accordance with previous findings). On the basis of these results it seems unlikely that nova Aql 82 (which shows strong carbon and oxygen enrichment together with heavier elements) can be explained by a nova event on a bare O-Ne-Mg white dwarf but is rather a result of burning with T> or approx.3.5 10 8 K. An application to existing nova models shows a reduced 26 Al production, when compared to earlier predictions. Both conclusions, however, have to be verified by complete nova calculations which include the improved nuclear physics input, presented here. (orig.)

Laser Program annual report, 1985

International Nuclear Information System (INIS)

Rufer, M.L.; Murphy, P.W.

1986-11-01

This volume presents the unclassified activities and accomplishments of the Inertial Confinement Fusion and Advanced Laser Development elements of the Laser Program at the Lawrence Livermore National Laboratory for the calendar year 1985. This report has been organized into major sections that correspond to our principal technical activities. Section 1 provides an overview. Section 2 comprises work in target theory, design, and code development. Target development and fabrication and the related topics in materials science are contained in Section 3. Section 4 presents work in experiments and diagnostics and includes developments in data acquisition and management capabilities. In Section 5 laser system (Nova) operation and maintenance are discussed. Activities related to supporting laser and optical technologies are described in Section 6. Basic laser research and development is reported in Section 7. Section 8 contains the results of studies in ICF applications where the work reported deals principally with the production of electric power with ICF. Finally, Section 9 is a comprehensive discussion of work to date on solid state lasers for average power applications. Individual sections, two through nine, have been cataloged separately

Laser Program annual report, 1985

Energy Technology Data Exchange (ETDEWEB)

Rufer, M.L.; Murphy, P.W. (eds.)

1986-11-01

This volume presents the unclassified activities and accomplishments of the Inertial Confinement Fusion and Advanced Laser Development elements of the Laser Program at the Lawrence Livermore National Laboratory for the calendar year 1985. This report has been organized into major sections that correspond to our principal technical activities. Section 1 provides an overview. Section 2 comprises work in target theory, design, and code development. Target development and fabrication and the related topics in materials science are contained in Section 3. Section 4 presents work in experiments and diagnostics and includes developments in data acquisition and management capabilities. In Section 5 laser system (Nova) operation and maintenance are discussed. Activities related to supporting laser and optical technologies are described in Section 6. Basic laser research and development is reported in Section 7. Section 8 contains the results of studies in ICF applications where the work reported deals principally with the production of electric power with ICF. Finally, Section 9 is a comprehensive discussion of work to date on solid state lasers for average power applications. Individual sections, two through nine, have been cataloged separately.

Searching for nova shells around cataclysmic variables

Science.gov (United States)

Sahman, D. I.; Dhillon, V. S.; Knigge, C.; Marsh, T. R.

2015-08-01

We present the results of a search for nova shells around 101 cataclysmic variables (CVs), using H α images taken with the 4.2-m William Herschel Telescope (WHT) and the 2.5-m Isaac Newton Telescope Photometric H α Survey of the Northern Galactic Plane (IPHAS). Both telescopes are located on La Palma. We concentrated our WHT search on nova-like variables, whilst our IPHAS search covered all CVs in the IPHAS footprint. We found one shell out of the 24 nova-like variables we examined. The newly discovered shell is around V1315 Aql and has a radius of ˜2.5 arcmin, indicative of a nova eruption approximately 120 yr ago. This result is consistent with the idea that the high mass-transfer rate exhibited by nova-like variables is due to enhanced irradiation of the secondary by the hot white dwarf following a recent nova eruption. The implications of our observations for the lifetime of the nova-like variable phase are discussed. We also examined four asynchronous polars, but found no new shells around any of them, so we are unable to confirm that a recent nova eruption is the cause of the asynchronicity in the white dwarf spin. We find tentative evidence of a faint shell around the dwarf nova V1363 Cyg. In addition, we find evidence for a light echo around the nova V2275 Cyg, which erupted in 2001, indicative of an earlier nova eruption ˜300 yr ago, making V2275 Cyg a possible recurrent nova.

Laser cutting system

Science.gov (United States)

Dougherty, Thomas J

2015-03-03

A workpiece cutting apparatus includes a laser source, a first suction system, and a first finger configured to guide a workpiece as it moves past the laser source. The first finger includes a first end provided adjacent a point where a laser from the laser source cuts the workpiece, and the first end of the first finger includes an aperture in fluid communication with the first suction system.

Broadband and short (10-ps) pulse generation on Nova

International Nuclear Information System (INIS)

Perry, M.D.; Browning, D.; Bibeau, C.; Patterson, F.G.; Wilcox, R.; Henesian, M.

1990-01-01

The ability to produce high power broadband pulses for purposes of focal spot beam smoothing has recently become an important issue in inertial confinement fusion (ICF). As the first step toward the generation and propagation of such pulses on Nova, the authors have performed a series of experiments with 10-ps pulses. Aside from the inherently broad bandwidth, these short pulses have important applications in ICF experiments and x-ray laser research. The author's experimental results are discussed. The short pulses were produced by diffraction grating pulse compression of chirped pulses formed from self-phase modulation in a single-mode 10-m fused silica fiber. Use of such a short fiber produces a nonlinearly chirped spectrum of 0.74 nm. The central nearly linearly chirped 0.26 nm is selected by polarization discrimination and compressed using 1800-line/mm diffraction gratings to a nearly Gaussian pulse of 10 ps FWHM with an energy contrast ratio of 20:1. This 1-nJ pulse is injected into a Nova amplifier chain with selected amplifiers unfired

Observations of classical novae in outburst

Science.gov (United States)

Starrfield, S.; Stryker, L. L.; Sonneborn, G.; Sparks, Warren M.; Ferland, Gary; Wagner, R. M.; Williams, R. E.; Gehrz, Robert D.; Ney, Edward P.; Kenyon, Scott

1988-01-01

The IUE obtained ultraviolet data on novae in outburst. The characteristics of every one of the outbursts are different. Optical and infrared data on many of the same novae were also obtained. Three members of the carbon-oxygen class of novae are presented.

High convergence, indirect drive inertial confinement fusion experiments at Nova

International Nuclear Information System (INIS)

Lerche, R.A.; Cable, M.D.; Hatchett, S.P.; Caird, J.A.; Kilkenny, J.D.; Kornblum, H.N.; Lane, S.M.; Laumann, C.; Murphy, T.J.; Murray, J.; Nelson, M.B.; Phillion, D.W.; Powell, H.; Ress, D.

1996-01-01

High convergence, indirect drive implosion experiments have been done at the Nova Laser Facility. The targets were deuterium and deuterium/tritium filled, glass microballoons driven symmetrically by x rays produced in a surrounding uranium hohlraum. Implosions achieved convergence ratios of 24:1 with fuel densities of 19 g/cm 3 ; this is equivalent to the range required for the hot spot of ignition scale capsules. The implosions used a shaped drive and were well characterized by a variety of laser and target measurements. The primary measurement was the fuel density using the secondary neutron technique (neutrons from the reaction 2 H( 3 H,n) 4 He in initially pure deuterium fuel). Laser measurements include power, energy and pointing. Simultaneous measurement of neutron yield, fusion reaction rate, and x-ray images provide additional information about the implosion process. Computer models are in good agreement with measurement results. copyright 1996 American Institute of Physics

Nucleosynthesis and the nova outburst

International Nuclear Information System (INIS)

Starrfield, S.

1995-01-01

A nova outburst is the consequence of the accretion of hydrogen rich material onto a white dwarf and it can be considered as the largest hydrogen bomb in the Universe. The fuel is supplied by a secondary star in a close binary system while the strong degeneracy of the massive white dwarf acts to contain the gas during the early stages of the explosion. The containment allows the temperature in the nuclear burning region to exceed 10 8 K under all circumstances. As a result a major fraction of CNO nuclei in the envelope are transformed into β + -unstable nuclei. We discuss the effects of these nuclei on the evolution. Recent observational studies have shown that there are two compositional classes of novae; one which occurs on carbon-oxygen white dwarfs, and a second class that occurs on oxygen-neon-magnesium white dwarfs. In this review we will concentrate on the latter explosions since they produce the most interesting nucleosynthesis. We report both on the results of new observational determinations of nova abundances and, in addition, new hydrodynamic calculations that examine the consequences of the accretion process on 1.0M circle-dot , 1.25M circle-dot , and 1.35M circle-dot white dwarfs. Our results show that novae can produce 22 Na, 26 Al, and other intermediate mass nuclei in interesting amounts. We will present the results of new calculations, done with updated nuclear reaction rates and opacities, which exhibit quantitative differences with respect to published work

"I feel like I am surviving the health care system": understanding LGBTQ health in Nova Scotia, Canada.

Science.gov (United States)

Colpitts, Emily; Gahagan, Jacqueline

2016-09-22

Currently, there is a dearth of baseline data on the health of lesbian, gay, bisexual, transgender, and queer (LGBTQ) populations in the province of Nova Scotia, Canada. Historically, LGBTQ health research has tended to focus on individual-level health risks associated with poor health outcomes among these populations, which has served to obscure the ways in which they maintain their own health and wellness across the life course. As such, there is an urgent need to shift the focus of LGBTQ health research towards strengths-based perspectives that explore the complex and resilient ways in which LGBTQ populations promote their health. This paper discusses the findings of our recent scoping review as well as the qualitative data to emerge from community consultations aimed at developing strengths-based approaches to understanding and advancing LGBTQ pathways to health across Nova Scotia. Our scoping review findings demonstrated the lack of strengths-based research on LGBTQ health in Nova Scotia. Specifically, the studies examined in our scoping review identified a number of health-promoting factors and a wide variety of measurement tools, some of which may prove useful for future strengths-based health research with LGBTQ populations. In addition, our community consultations revealed that many participants had negative experiences with health care systems and services in Nova Scotia. However, participants also shared a number of factors that contribute to LGBTQ health and suggestions for how LGBTQ pathways to health in Nova Scotia can be improved. There is an urgent need to conduct research on the health needs, lived experiences, and outcomes of LGBTQ populations in Nova Scotia to address gaps in our knowledge of their unique health needs. In moving forward, it is important that future health research take an intersectional, strengths-based perspective in an effort to highlight the factors that promote LGBTQ health and wellness across the life course, while taking

Application of Various Lasers to Laser Trimming Resistance System

Institute of Scientific and Technical Information of China (English)

SUN Ji-feng

2007-01-01

Though the laser trimming resistance has been an old laser machining industry for over 30 years, the development of technology brings new alternative lasers which can be used for the traditional machining. The paper describes application of various lasers to laser trimming resistance system including early traditional krypton arc lamp pumped Nd:YAG to laser, modern popular diode pumped solid state laser and the present advanced harmonic diode pumped solid state laser. Using the new alternative lasers in the laser trimming resistance system can dramatically improve the yields and equipment performance.

Nova-driven winds in globular clusters

International Nuclear Information System (INIS)

Scott, E.H.; Durisen, R.H.

1978-01-01

Recent sensitive searches for Hα emission from ionized intracluster gas in globular clusters have set upper limits that conflict with theoretical predictions. We suggest that nova outbursts heat the gas, producing winds that resolve this discrepancy. The incidence of novae in globular clusters, the conversion of kinetic energy of the nova shell to thermal energy of the intracluster gas, and the characteristics of the resultant winds are discussed. Calculated emission from the nova-driven models does not conflict with any observations to date. Some suggestions are made concerning the most promising approaches for future detection of intracluster gas on the basis of these models. The possible relationship of nova-driven winds of globular cluster X-ray sources is also considered

High power lasers & systems

OpenAIRE

Chatwin, Chris; Young, Rupert; Birch, Philip

2015-01-01

Some laser history;\\ud Airborne Laser Testbed & Chemical Oxygen Iodine Laser (COIL);\\ud Laser modes and beam propagation;\\ud Fibre lasers and applications;\\ud US Navy Laser system – NRL 33kW fibre laser;\\ud Lockheed Martin 30kW fibre laser;\\ud Conclusions

Sub-nanosecond cinematography in laser fusion research: current techniques and applications at the Lawrence Livermore National Laboratory

Energy Technology Data Exchange (ETDEWEB)

Coleman, L.W.

1985-01-10

Progress in laser fusion research has increased the need for detail and precision in the diagnosis of experiments. This has spawned the development and use of sophisticated sub-nanosecond resolution diagnostic systems. These systems typically use ultrafast x-ray or optical streak cameras in combination with spatially imaging or spectrally dispersing elements. These instruments provide high resolution data essential for understanding the processes occurring in the interaction of high intensity laser light with targets. Several of these types of instruments and their capabilities will be discussed. The utilization of these kinds of diagnostics systems on the nearly completed 100 kJ Nova laser facility will be described.

Inertial fusion results from Nova and implication for the future of ICF

International Nuclear Information System (INIS)

Kilkenny, J.D.; Cable, M.D.; Campbell, E.M.

1988-10-01

A key objective of the US Inertial Confinement Fusion Program is to obtain high yield (100-1000 MJ) implosions in a laboratory environment. This requires high grain from an inertial fusion target from a driver capable of delivering about 10 MJ. Recent results have been sufficiently encouraging that the US Department of Energy is planning for such a capability called the Laboratory Microfusion Facility (LMF). In the past two years, we have conducted implosion-related experiments with approximately 20 kJ of 0.35-μm laser light in 1-ns temporally flat-topped pulses. These experiments were done with the Nova laser, the primary US facility devoted to radiatively driven inertial confinement fusion. Our results show that we can accurately model a significant fraction of the phenomena required to obtain the fuel conditions needed for high gain. Both the x-ray conversion efficiency and the growth of Rayleigh-Taylor hydrodynamic instabilities are shown to be at acceptable levels. Targets designed so that the shape of the stagnated fuel can be imaged show that the x-ray drive in our hohlraums can be made isotropic to better than 3%. With this optimized drive and temporally unshaped laser pulses many critical implosion parameters are measured on targets designed for higher density. Good agreement is obtained with one-dimensional simulations. Maximum compressions of between 20--30 in radius are measured with a variety of diagnostics. Improvements in the driver technology are demonstrated; we anticipate operation of Nova at the 50-kJ level at 3ω. 18 refs., 6 figs., 1 tab

Polarimetry and spectroscopy of the "oxygen flaring" DQ Herculis-like nova: V5668 Sagittarii (2015)

Science.gov (United States)

Harvey, E. J.; Redman, M. P.; Darnley, M. J.; Williams, S. C.; Berdyugin, A.; Piirola, V. E.; Fitzgerald, K. P.; O'Connor, E. G. P.

2018-03-01

Context. Classical novae are eruptions on the surface of a white dwarf in a binary system. The material ejected from the white dwarf surface generally forms an axisymmetric shell of gas and dust around the system. The three-dimensional structure of these shells is difficult to untangle when viewed on the plane of the sky. In this work a geometrical model is developed to explain new observations of the 2015 nova V5668 Sagittarii. Aim. We aim to better understand the early evolution of classical nova shells in the context of the relationship between polarisation, photometry, and spectroscopy in the optical regime. To understand the ionisation structure in terms of the nova shell morphology and estimate the emission distribution directly following the light curve's dust-dip. Methods: High-cadence optical polarimetry and spectroscopy observations of a nova are presented. The ejecta is modelled in terms of morpho-kinematics and photoionisation structure. Results: Initially observational results are presented, including broadband polarimetry and spectroscopy of V5668 Sgr nova during eruption. Variability over these observations provides clues towards the evolving structure of the nova shell. The position angle of the shell is derived from polarimetry, which is attributed to scattering from small dust grains. Shocks in the nova outflow are suggested in the photometry and the effect of these on the nova shell are illustrated with various physical diagnostics. Changes in density and temperature as the super soft source phase of the nova began are discussed. Gas densities are found to be of the order of 109 cm-3 for the nova in its auroral phase. The blackbody temperature of the central stellar system is estimated to be around 2.2 × 105 K at times coincident with the super soft source turn-on. It was found that the blend around 4640 Å commonly called "nitrogen flaring" is more naturally explained as flaring of the O II multiplet (V1) from 4638-4696 Å, i.e. "oxygen flaring

Gamma-ray emission from internal shocks in novae

Science.gov (United States)

Martin, P.; Dubus, G.; Jean, P.; Tatischeff, V.; Dosne, C.

2018-04-01

Context. Gamma-ray emission at energies ≥100 MeV has been detected from nine novae using the Fermi Large Area Telescope (LAT), and can be explained by particle acceleration at shocks in these systems. Eight out of these nine objects are classical novae in which interaction of the ejecta with a tenuous circumbinary material is not expected to generate detectable gamma-ray emission. Aim. We examine whether particle acceleration at internal shocks can account for the gamma-ray emission from these novae. The shocks result from the interaction of a fast wind radiatively-driven by nuclear burning on the white dwarf with material ejected in the initial runaway stage of the nova outburst. Methods: We present a one-dimensional model for the dynamics of a forward and reverse shock system in a nova ejecta, and for the associated time-dependent particle acceleration and high-energy gamma-ray emission. Non-thermal proton and electron spectra are calculated by solving a time-dependent transport equation for particle injection, acceleration, losses, and escape from the shock region. The predicted emission is compared to LAT observations of V407 Cyg, V1324 Sco, V959 Mon, V339 Del, V1369 Cen, and V5668 Sgr. Results: The ≥100 MeV gamma-ray emission arises predominantly from particles accelerated up to 100 GeV at the reverse shock and undergoing hadronic interactions in the dense cooling layer downstream of the shock. The emission rises within days after the onset of the wind, quickly reaches a maximum, and its subsequent decrease reflects mostly the time evolution of the wind properties. Comparison to gamma-ray data points to a typical scenario where an ejecta of mass 10-5-10-4 M⊙ expands in a homologous way with a maximum velocity of 1000-2000 km s-1, followed within a day by a wind with a velocity values of which result in the majority of best-fit models having gamma-ray spectra with a high-energy turnover below 10 GeV. Our typical model is able to account for the main

Laser transmitter system

International Nuclear Information System (INIS)

Dye, R.A.

1975-01-01

A laser transmitter system is disclosed which utilizes mechanical energy for generating an output pulse. The laser system includes a current developing device such as a piezoelectric crystal which charges a storage device such as a capacitor in response to a mechanical input signal. The capacitor is coupled to a switching device, such as a silicon controlled rectifier (SCR). The switching device is coupled to a laser transmitter such as a GaAs laser diode, which provides an output signal in response to the capacitor being discharged

The NOvA software testing framework

International Nuclear Information System (INIS)

Tamsett, M; Group, C

2015-01-01

The NOvA experiment at Fermilab is a long-baseline neutrino experiment designed to study vε appearance in a vμ beam. NOvA has already produced more than one million Monte Carlo and detector generated files amounting to more than 1 PB in size. This data is divided between a number of parallel streams such as far and near detector beam spills, cosmic ray backgrounds, a number of data-driven triggers and over 20 different Monte Carlo configurations. Each of these data streams must be processed through the appropriate steps of the rapidly evolving, multi-tiered, interdependent NOvA software framework. In total there are greater than 12 individual software tiers, each of which performs a different function and can be configured differently depending on the input stream. In order to regularly test and validate that all of these software stages are working correctly NOvA has designed a powerful, modular testing framework that enables detailed validation and benchmarking to be performed in a fast, efficient and accessible way with minimal expert knowledge. The core of this system is a novel series of python modules which wrap, monitor and handle the underlying C++ software framework and then report the results to a slick front-end web-based interface. This interface utilises modern, cross-platform, visualisation libraries to render the test results in a meaningful way. They are fast and flexible, allowing for the easy addition of new tests and datasets. In total upwards of 14 individual streams are regularly tested amounting to over 70 individual software processes, producing over 25 GB of output files. The rigour enforced through this flexible testing framework enables NOvA to rapidly verify configurations, results and software and thus ensure that data is available for physics analysis in a timely and robust manner. (paper)

Synoptic GNIRS XD Spectra ToO Novae

Science.gov (United States)

Woodward, Chick; Helton, Andrew; Spitzer/Chandra Team

2007-02-01

Novae are important contributors to galactic chemical enrichment on local scales. NIR spectroscopy of novae provides information about the elemental abundances of the gas and dust in the ejecta dispersing into the ISM as well as kinematic information related to the outburst. We propose to obtain synoptic GNIRS spectra of select Target of Opportunity (ToO) novae in the Magellanic Clouds (MC) and the galaxy to study the dynamics of the ejecta, to determine the temporal evolution of coronal lines and recombination lines (measuring their strength and velocity profiles), and to determine abundances. Being all equidistant, MC nova permit a more robust analysis of distant-dependent physical parameters of outburst than is generally possible for Galactic novae. The GNIRS data will provide critical spectral coverage and synoptic data to complement extant Spitzer and Chandra nova programs. Triggering of the GNIRS program will occur when a nova becomes brighter than V=12 mag, (assuming that adequate PWFS guide stars exist) as reported in the IAUC or CBET.

Target isolation system, high power laser and laser peening method and system using same

Science.gov (United States)

Dane, C. Brent; Hackel, Lloyd A.; Harris, Fritz

2007-11-06

A system for applying a laser beam to work pieces, includes a laser system producing a high power output beam. Target delivery optics are arranged to deliver the output beam to a target work piece. A relay telescope having a telescope focal point is placed in the beam path between the laser system and the target delivery optics. The relay telescope relays an image between an image location near the output of the laser system and an image location near the target delivery optics. A baffle is placed at the telescope focal point between the target delivery optics and the laser system to block reflections from the target in the target delivery optics from returning to the laser system and causing damage.

Restablished Accretion in Post-outburst Classical Novae Revealed by X-rays

Science.gov (United States)

Hernanz, Margarita; Ferri, Carlo; Sala, Glòria

2009-05-01

Classical novae are explosions on accreting white dwarfs (hereinafter WDs) in cataclysmic variables (hereinafter CVs) a hydrogen thermonuclear runaway on top of the WD is responsible for the outburst. X-rays provide a unique way to study the turn-off of H-burning, because super soft X-rays reveal the hot WD photosphere, but also to understand how accretion is established again in the binary system. Observations with XMM-Newton of some post-outburst novae have revealed such a process, but a coverage up to larger energies -as Simbol-X will provide- is fundamental to well understand the characteristics of the binary system and of the nova ejecta. We present a brief summary of our results up to now and prospects for the Simbol-X mission.

Message Correlation Analysis Tool for NOvA

International Nuclear Information System (INIS)

Lu Qiming; Biery, Kurt A; Kowalkowski, James B

2012-01-01

A complex running system, such as the NOvA online data acquisition, consists of a large number of distributed but closely interacting components. This paper describes a generic real-time correlation analysis and event identification engine, named Message Analyzer. Its purpose is to capture run time abnormalities and recognize system failures based on log messages from participating components. The initial design of analysis engine is driven by the data acquisition (DAQ) of the NOvA experiment. The Message Analyzer performs filtering and pattern recognition on the log messages and reacts to system failures identified by associated triggering rules. The tool helps the system maintain a healthy running state and to minimize data corruption. This paper also describes a domain specific language that allows the recognition patterns and correlation rules to be specified in a clear and flexible way. In addition, the engine provides a plugin mechanism for users to implement specialized patterns or rules in generic languages such as C++.

Message Correlation Analysis Tool for NOvA

CERN Multimedia

CERN. Geneva

2012-01-01

A complex running system, such as the NOvA online data acquisition, consists of a large number of distributed but closely interacting components. This paper describes a generic realtime correlation analysis and event identification engine, named Message Analyzer. Its purpose is to capture run time abnormalities and recognize system failures based on log messages from participating components. The initial design of analysis engine is driven by the DAQ of the NOvA experiment. The Message Analyzer performs filtering and pattern recognition on the log messages and reacts to system failures identified by associated triggering rules. The tool helps the system maintain a healthy running state and to minimize data corruption. This paper also describes a domain specific language that allows the recognition patterns and correlation rules to be specified in a clear and flexible way. In addition, the engine provides a plugin mechanism for users to implement specialized patterns or rules in generic languages such as C++.

Message correlation analysis tool for NOvA

Energy Technology Data Exchange (ETDEWEB)

Lu, Qiming [Fermilab; Biery, Kurt A. [Fermilab; Kowalkowski, James B. [Fermilab

2012-01-01

A complex running system, such as the NOvA online data acquisition, consists of a large number of distributed but closely interacting components. This paper describes a generic real-time correlation analysis and event identification engine, named Message Analyzer. Its purpose is to capture run time abnormalities and recognize system failures based on log messages from participating components. The initial design of analysis engine is driven by the data acquisition (DAQ) of the NOvA experiment. The Message Analyzer performs filtering and pattern recognition on the log messages and reacts to system failures identified by associated triggering rules. The tool helps the system maintain a healthy running state and to minimize data corruption. This paper also describes a domain specific language that allows the recognition patterns and correlation rules to be specified in a clear and flexible way. In addition, the engine provides a plugin mechanism for users to implement specialized patterns or rules in generic languages such as C++.

Bonding performance of universal adhesives to er,cr:YSGG laser-irradiated enamel.

Science.gov (United States)

Ayar, Muhammet Kerim; Erdemir, Fatih

2017-04-01

Universal adhesives have been recently introduced for use as self-etch or etch-and-rinse adhesives depending on the dental substrate and clinical condition. However, their bonding effectiveness to laser-irradiated enamel is still not well-known. Thus, the aim of this study was to compare the shear bond strength (SBS) of universal adhesives (Single Bond Universal; Nova Compo-B Plus) applied to Er,Cr:YSGG laser-irradiated enamel with SBS of the same adhesives applied in self-etch and acid-etching modes, respectively. Crown segments of sixty bovine incisors were embedded into standardized acrylic blocks. Flattened enamel surfaces were prepared. Specimens were divided into six groups according to universal adhesives and application modes randomly (n = 10), as follows: Single Bond Universal/acid-etching mode; Nova Compo-B Plus/acid-etching mode; Single Bond Universal/self-etching mode; Nova Compo-B Plus/self-etching mode; and Single Bond Universal/Er,Cr:YSGG Laser-etching mode; Nova Compo-B Plus/Er,Cr:YSGG Laser-etching mode. After surface treatments, universal adhesives were applied onto surfaces. SBS was determined after storage in water for 24 h using a universal testing machine with a crosshead speed of 0.5 mm min -1 . Failure modes were evaluated using a stereomicroscope. Data was analyzed using two-way of analyses of variances (ANOVA) (p = 0.05). Two-way ANOVA revealed that adhesive had no effect on SBS (p = 0.88), but application mode significantly influenced SBS (p = 0.00). Acid-etching significantly increased SBS, whereas there are no significant differences between self-etch mode and laser-etching for both adhesives. The bond strength of universal adhesives may depend on application mode. Acid etching may significantly increase bond strength, while laser etching may provide similar bond strength when compared to self-etch mode. © 2016 Wiley Periodicals, Inc.

Policy statement on gas distribution in Nova Scotia

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-01-30

This paper presented Nova Scotia's policy related to gas distribution. The government of Nova Scotia views natural gas as an economic enabler and is committed to ensuring that natural gas is available and accessible to Nova Scotians where it is economically feasible. Natural gas will give the province an efficient and clean burning energy supply that will make existing businesses more competitive. The province will support and facilitate the construction and operation of a gas distribution system by the private sector and will ensure that there is regulatory oversight by the Nova Scotia Utility and Review Board to protect the public interest. The government will also develop a plan for early conversion of government buildings to natural gas. This paper described the province's policy on gas distribution in relation to: (1) a province-wide franchise, (2) a supplemental franchise, (3) cost of service/performance based rates, (4) postage stamp rates, (5) a Maritimes and Northeast lateral policy, (6) direct access/bypass, (7) existing direct access user, (8) bundling of gas sales and other products and services, (9) licensing of gas marketers, (10) benefits, (11), regulatory efficiency, (12) municipal taxes, and (13) municipal operating agreements.

A multiwavelength study of superoutbursts in dwarf novae

International Nuclear Information System (INIS)

Woerd, H.J. van der.

1987-01-01

Dwarf novae are stellar systems consisting of two stars which orbit around each other within a few hours. In dwarf novae one of the stars, which is a bit smaller and less massive than our sun, loses matter to a very compact and degenerated star: a white dwarf. This white dwarf has nearly the same mass as our sun but its radius is about a hundred times smaller. The process of mass transport was studied on the basis of observations with the Exosat-satelite (European X-ray Observatory satelite). 397 refs.; 50 figs.; 21 tabs

The Distance to Nova V959 Mon from VLA Imaging

Science.gov (United States)

Linford, J. D.; Ribeiro, V. A. R. M.; Chomiuk, L.; Nelson, T.; Sokoloski, J. L.; Rupen, M. P.; Mukai, K.; O'Brien, T. J.; Mioduszewski, A. J.; Weston, J.

2015-06-01

Determining reliable distances to classical novae is a challenging but crucial step in deriving their ejected masses and explosion energetics. Here we combine radio expansion measurements from the Karl G. Jansky Very Large Array with velocities derived from optical spectra to estimate an expansion parallax for nova V959 Mon, the first nova discovered through its γ-ray emission. We spatially resolve the nova at frequencies of 4.5-36.5 GHz in nine different imaging epochs. The first five epochs cover the expansion of the ejecta from 2012 October to 2013 January, while the final four epochs span 2014 February-May. These observations correspond to days 126 through 199 and days 615 through 703 after the first detection of the nova. The images clearly show a non-spherical ejecta geometry. Utilizing ejecta velocities derived from three-dimensional modeling of optical spectroscopy, the radio expansion implies a distance between 0.9 ± 0.2 and 2.2 ± 0.4 kpc, with a most probable distance of 1.4 ± 0.4 kpc. This distance implies a γ-ray luminosity of 0.6× {{10}35} erg s-1, which is much less than the prototype γ-ray-detected nova, V407 Cyg, possibly due to the lack of a red giant companion in the V959 Mon system. V959 Mon also has a much lower γ-ray luminosity than other classical novae detected in γ-rays to date, indicating a range of at least a factor of 10 in the γ-ray luminosities for these explosions.

Statistical analysis of dwarf nova outbursts

International Nuclear Information System (INIS)

Gicger, A.

1987-01-01

Correlation between maximum brightness, outburst width, lengths of preceding and following intervals has been studied for 14 dwarf novae (mostly from southern sky). Significant correlations (ρ ≥ 0.4) occur only in 16 per cent of cases, what confirms earlier results of Szkody and Mattei (1984). Global correlations have also been studied between mean photometric parameters and binary system parameters using a sample including over 30 objects. The most interesting result is the strong correlation (ρ = +0.94) between the orbital period and the outburst duration. It implies that the quantity α(z 0 /r) 2 is approximately constant for all dwarf novae. Using typical estimates for z 0 /r we get α = 0.2. 30 refs., 1 figs., 2 tabs. (author)

Radiation drive in laser heated hohlraums

International Nuclear Information System (INIS)

Suter, L.J.; Kauffman, R.L.; Darrow, C.B.

1995-01-01

Nearly 10 years of Nova experiments and analysis have lead to a relatively detailed quantitative and qualitative understanding of radiation drive in laser heated hohlraums. Our most successful quantitative modelling tool is 2D Lasnex numerical simulations. Analysis of the simulations provides us with insight into the details of the hohlraum drive. In particular we find hohlraum radiation conversion efficiency becomes quite high with longer pulses as the accumulated, high Z blow-off plasma begins to radiate. Extensive Nova experiments corroborate our quantitative and qualitative understanding

Compact 5 x 1012 AMP/SEC rail-gun pulser for a laser plasma shutter

International Nuclear Information System (INIS)

Bradley, L.P.; Orham, E.L.; Stowers, I.F.

1979-01-01

We have developed a rail-gun plasma source to produce a plasma of 10 12 cm -3 particle density and project it with a velocity of 3.9 cm/μs. This device will be used in a output spatial filter of Nova to project a critical density plasma across an optical beam path and block laser retroreflected light. The object of this paper is to describe the design of a pulser appropriate to the Shiva laser fusion facility, and to describe the preliminary design of a higher current prototype pulser for Nova the laser fusion research facility under construction at Lawrence Livermore Laboratory

Recurrent Novae — A Review

Directory of Open Access Journals (Sweden)

K. Mukai

2015-02-01

Full Text Available In recent years, recurrent nova eruptions are often observed very intensely in wide range of wavelengths from radio to optical to X-rays. Here I present selected highlights from recent multi-wavelength observations. The enigma of T Pyx is at the heart of this paper. While our current understanding of CV and symbiotic star evolution can explain why certain subset of recurrent novae have high accretion rate, that of T Pyx must be greatly elevated compared to the evolutionary mean. At the same time, we have extensive data to be able to estimate how the nova envelope was ejected in T Pyx, and it turns to be a rather complex tale. One suspects that envelope ejection in recurrent and classical novae in general is more complicated than the textbook descriptions. At the end of the review, I will speculate that these two may be connected.

a Synoptic Study of AN X-Ray Nova in Outburst

Science.gov (United States)

McClintock, Jeffrey

Optical studies of X-ray novae in quiescence have yielded compelling evidence for black holes in binary systems. However, X-ray studies in quiescence are severely constrained by the near absence of high energy emission. Thus, further observational advances in black hole astrophysics require a substantial commitment to observe X-ray novae in outburst in just that spectral range accessible to XTE. We propose an agressive campaign of X-ray observations of the next non-pulsing X-ray nova that rises above 3 Crab at 2-10 keV. We further propose a coordinated and intensive campaign of optical and radio observations covering both hemispheres. The observations will provide a full temporal and spectral view of the outburst cycle.

Powering laser diode systems

CERN Document Server

Trestman, Grigoriy A

2017-01-01

This Tutorial Text discusses the competent design and skilled use of laser diode drivers (LDDs) and power supplies (PSs) for the electrical components of laser diode systems. It is intended to help power-electronic design engineers during the initial design stages: the choice of the best PS topology, the calculation of parameters and components of the PS circuit, and the computer simulation of the circuit. Readers who use laser diode systems for research, production, and other purposes will also benefit. The book will help readers avoid errors when creating laser systems from ready-made blocks, as well as understand the nature of the "mystical failures" of laser diodes (and possibly prevent them).

Theory of Nova Outbursts and Type Ia Supernovae

Directory of Open Access Journals (Sweden)

M. Kato

2015-02-01

Full Text Available We briefly review the current theoretical understanding of the light curves of novae. These curves exhibit a homologous nature, dubbed the universal decline law, and when time-normalized, they almost follow a single curve independently of the white dwarf (WD mass or chemical composition of the envelope. The optical and near-infrared light curves of novae are reproduced mainly by free-free emission from their optically thick winds. We can estimate the WD mass from multiwavelength observations because the optical, UV, and soft X-ray light curves evolve differently and we can easily resolve the degeneracy of the optical light curves. Recurrent novae and classical novae are a testbed of type Ia supernova scenarios. In the orbital period versus secondary mass diagram, recurrent novae are located in different regions from classical novae and the positions of recurrent novae are consistent with the single degenerate scenario.

Infrared laser system

International Nuclear Information System (INIS)

Cantrell, C.D.; Carbone, R.J.

1977-01-01

An infrared laser system and method for isotope separation may comprise a molecular gas laser oscillator to produce a laser beam at a first wavelength, Raman spin flip means for shifting the laser to a second wavelength, a molecular gas laser amplifier to amplify said second wavelength laser beam to high power, and optical means for directing the second wavelength, high power laser beam against a desired isotope for selective excitation thereof in a mixture with other isotopes. The optical means may include a medium which shifts the second wavelength high power laser beam to a third wavelength, high power laser beam at a wavelength coincidental with a corresponding vibrational state of said isotope and which is different from vibrational states of other isotopes in the gas mixture

Using the Nova target chamber for high-yield targets

International Nuclear Information System (INIS)

Pitts, J.H.

1987-01-01

The existing 2.2-m-radius Nova aluminum target chamber, coated and lined with boron-seeded carbon shields, is proposed for use with 1000-MJ-yield targets in the next laser facility. The laser beam and diagnostic holes in the target chamber are left open and the desired 10 -2 Torr vacuum is maintained both inside and outside the target chamber; a larger target chamber room is the vacuum barrier to the atmosphere. The hole area available is three times that necessary to maintain a maximum fluence below 12 J/cm 2 on optics placed at a radius of 10 m. Maximum stress in the target chamber wall is 73 MPa, which complies with the intent of the ASME Pressure Vessel Code. However, shock waves passing through the inner carbon shield could cause it to comminute. We propose tests and analyses to ensure that the inner carbon shield survives the environment. 13 refs

Franchising in Nova Scotia

Energy Technology Data Exchange (ETDEWEB)

Hoffman, G. [Nova Scotia Petroleum Directorate, Halifax, NS (Canada)

1998-09-01

Opportunities for the local distribution of natural gas in Nova Scotia were reviewed, with special emphasis on franchising. Franchising in Nova Scotia began in 1980, made possible by the passage of the Gas Utilities Act and the Pipeline Act which promised western Canadian natural gas to eastern Canada. However, proposals for franchisees to distribute natural gas in the province were abandoned as the hope for natural gas transmission service to the province faded. The plummeting of world oil prices by the mid-1980s was also a contributory factor. Discovery and development of natural gas facilities around Sable Island led to the September 1997 proclamation of the Gas Distribution Act, which also led to the revival of interest in franchising. The Act provides for the competitive marketing of natural gas as a commodity and the regulation of the gas delivery system under a franchise agreement. Competitive applications are expected early in 1998, with awards of franchises in late 1998. Construction and gas delivery services should begin operations late in 1999.

Franchising in Nova Scotia

International Nuclear Information System (INIS)

Hoffman, G.

1998-01-01

Opportunities for the local distribution of natural gas in Nova Scotia were reviewed, with special emphasis on franchising. Franchising in Nova Scotia began in 1980, made possible by the passage of the Gas Utilities Act and the Pipeline Act which promised western Canadian natural gas to eastern Canada. However, proposals for franchisees to distribute natural gas in the province were abandoned as the hope for natural gas transmission service to the province faded. The plummeting of world oil prices by the mid-1980s was also a contributory factor. Discovery and development of natural gas facilities around Sable Island led to the September 1997 proclamation of the Gas Distribution Act, which also led to the revival of interest in franchising. The Act provides for the competitive marketing of natural gas as a commodity and the regulation of the gas delivery system under a franchise agreement. Competitive applications are expected early in 1998, with awards of franchises in late 1998. Construction and gas delivery services should begin operations late in 1999

Nova Scotia's new gas distribution regime

Energy Technology Data Exchange (ETDEWEB)

MacIsaac, J.B. [Cox Hanson O' Reilly Matheson, Halifax, NS (Canada)

2002-07-01

The most recent amendments to Nova Scotia's gas distribution regime were described in detail. The amended legislation includes: (1) elimination of mandatory service targets, (2) franchise terms of 25 years, (3) a 10 year prohibition on industrial by-pass, (4) gas sales licenses are now required to market gas in Nova Scotia, (5) distributors can offer bundled services, (6) the elimination of province wide uniform tolls for low volume customers, (7) public utilities are permitted to apply for a distribution franchise and to market natural gas, (8) ex-party filing of interim rates, (9) the Pipeline Act applies to the construction of gas distribution systems, (10) socio-economic studies are required for parties seeking a single-end user franchise outside a franchise area, and (11) regulations for underground gas storage have been removed from the legislation. It was noted that these significant changes to the statutory framework of Nova Scotia's delivery of natural gas are sending encouraging signals to parties considering investing in the distribution network in the province. It was also noted, that as in any industry, success of natural gas distribution in Nova Scotia will depend on economics and not on structural changes. 66 refs.

Bossa Nova

DEFF Research Database (Denmark)

Petersen, Nicoline Jacoby; Bræstrup, Lise

"Bossa Nova" giver dig de bedste bud på, hvordan du takler den menneskelige dimension i ledelse. Når du bevæger dig ud på gulvet, opstår der konflikter, kærlighed, jalousi og vrede. Pludselig opdager du, at medarbejdere tænker meget anderledes end dig selv, har forskellige behov og af og til......, kriser og meget andet. Her er værdifulde iagttagelser og tips, som enhver leder ? uanset branche ? kan bruge i sin dagligdag. "Bossa Nova" er uundværlig for den, der vil lære mere om, hvordan man får mennesker til at præstere det sublime, så ledelse bliver en dans, hvor alle kan følge takten....

Laser plasma interactions in hohlraums

Energy Technology Data Exchange (ETDEWEB)

Kruer, W.L.

1994-10-05

Lasers plasma instabilities are an important constraint in x-ray driven inertial confinement fusion. In hohlraums irradiated with 1.06 {mu}m light on the Shiva laser, plasma instabilities were extremely deleterious, driving the program to the use of shorter wavelength light. Excellent coupling has been achieved in hohlraums driven with 0.35 {mu}m light on the Nova laser. Considerable attention is being given to the scaling of this excellent coupling to the larger hohlraums for an ignition target. Various instability control mechanisms such as large plasma wave damping and laser beam incoherence are discussed, as well as scaling experiments to check the instability levels.

Absolute spectrophotometry of Nova Cygni 1975

International Nuclear Information System (INIS)

Kontizas, E.; Kontizas, M.; Smyth, M.J.

1976-01-01

Radiometric photoelectric spectrophotometry of Nova Cygni 1975 was carried out on 1975 August 31, September 2, 3. α Lyr was used as reference star and its absolute spectral energy distribution was used to reduce the spectrophotometry of the nova to absolute units. Emission strengths of Hα, Hβ, Hγ (in W cm -2 ) were derived. The Balmer decrement Hα:Hβ:Hγ was compared with theory, and found to deviate less than had been reported for an earlier nova. (author)

A Hubble Space Telescope survey for novae in M87 - III. Are novae good standard candles 15 d after maximum brightness?

Science.gov (United States)

Shara, Michael M.; Doyle, Trisha F.; Pagnotta, Ashley; Garland, James T.; Lauer, Tod R.; Zurek, David; Baltz, Edward A.; Goerl, Ariel; Kovetz, Attay; Machac, Tamara; Madrid, Juan P.; Mikołajewska, Joanna; Neill, J. D.; Prialnik, Dina; Welch, D. L.; Yaron, Ofer

2018-02-01

Ten weeks of daily imaging of the giant elliptical galaxy M87 with the Hubble Space Telescope (HST) has yielded 41 nova light curves of unprecedented quality for extragalactic cataclysmic variables. We have recently used these light curves to demonstrate that the observational scatter in the so-called maximum-magnitude rate of decline (MMRD) relation for classical novae is so large as to render the nova-MMRD useless as a standard candle. Here, we demonstrate that a modified Buscombe-de Vaucouleurs hypothesis, namely that novae with decline times t2 > 10 d converge to nearly the same absolute magnitude about two weeks after maximum light in a giant elliptical galaxy, is supported by our M87 nova data. For 13 novae with daily sampled light curves, well determined times of maximum light in both the F606W and F814W filters, and decline times t2 > 10 d we find that M87 novae display M606W,15 = -6.37 ± 0.46 and M814W,15 = -6.11 ± 0.43. If very fast novae with decline times t2 < 10 d are excluded, the distances to novae in elliptical galaxies with stellar binary populations similar to those of M87 should be determinable with 1σ accuracies of ± 20 per cent with the above calibrations.

Photometry and polarimetry of Nova Andromedae 1986

Energy Technology Data Exchange (ETDEWEB)

Kikuchi, Sen; Mikami, Yoshitaka; Kondo, Masayuki

1988-01-01

We have carried out photometry of Nova Andromedae 1986 and find that it should be classified as a fast nova. We have also made polarimetry simultaneously at six wavelengths between 0.36-0.70 ..mu..m. The polarization increased between 2 and 22 days after the light maximum showing that dust formation was associated with the nova explosion.

Data Driven Trigger Design and Analysis for the NOvA Experiment

Energy Technology Data Exchange (ETDEWEB)

Kurbanov, Serdar [Univ. of Virginia, Charlottesville, VA (United States)

2016-01-01

This thesis primarily describes analysis related to studying the Moon shadow with cosmic rays, an analysis using upward-going muons trigger data, and other work done as part of MSc thesis work conducted at Fermi National Laboratory. While at Fermilab I made hardware and software contributions to two experiments - NOvA and Mu2e. NOvA is a neutrino experiment with the primary goal of measuring parameters related to neutrino oscillation. This is a running experiment, so it's possible to provide analysis of real beam and cosmic data. Most of this work was related to the Data-Driven Trigger (DDT) system of NOvA. The results of the Upward-Going muon analysis was presented at ICHEP in August 2016. The analysis demonstrates the proof of principle for a low-mass dark matter search. Mu2e is an experiment currently being built at Fermilab. Its primary goal is to detect the hypothetical neutrinoless conversion from a muon into an electron. I contributed to the production and tests of Cathode Strip Chambers (CSCs) which are required for testing the Cosmic Ray Veto (CRV) system for the experiment. This contribution is described in the last chapter along with a short description of the technical work provided for the DDT system of the NOvA experiment. All of the work described in this thesis will be extended by the next generation of UVA graduate students and postdocs as new data is collected by the experiment. I hope my eorts of have helped lay the foundation for many years of beautiful results from Mu2e and NOvA.

Magnetic novae

Science.gov (United States)

Zemko, Polina; Orio, Marina

2016-07-01

We present the results of optical and X-ray observations of two quiescent novae, V2491 Cyg and V4743 Sgr. Our observations suggest the intriguing possibility of localization of hydrogen burning in magnetic novae, in which accretion is streamed to the polar caps. V2491 Cyg was observed with Suzaku more than 2 years after the outburst and V4743 Sgr was observed with XMM Newton 2 and 3.5 years after maximum. In the framework of a monitoring program of novae previously observed as super soft X-ray sources we also obtained optical spectra of V4743 Sgr with the SALT telescope 11.5 years after the eruption and of V2491 Cyg with the 6m Big Azimutal Telescope 4 and 7 years post-outburst. In order to confirm the possible white dwarf spin period of V2491 Cyg measured in the Suzaku observations we obtained photometric data using the 90cm WIYN telescope at Kitt Peak and the 1.2 m telescope in Crimea. We found that V4743 Sgr is an intermediate polar (IP) and V2491 Cyg is a strong IP candidate. Both novae show modulation of their X-ray light curves and have X-ray spectra typical of IPs. The Suzaku and XMM Newton exposures revealed that the spectra of both novae have a very soft blackbody-like component with a temperature close to that of the hydrogen burning white dwarfs in their SSS phases, but with flux by at least two orders of magnitude lower, implying a possible shrinking of emitting regions in the thin atmosphere that is heated by nuclear burning underneath it. In quiescent IPs, independently of the burning, an ultrasoft X-ray flux component originates at times in the polar regions irradiated by the accretion column, but the soft component of V4743 Sgr disappeared in 2006, indicating that the origin may be different from accretion. We suggest it may have been due to an atmospheric temperature gradient on the white dwarf surface, or to continuing localized thermonuclear burning at the bottom of the envelope, before complete turn-off. The optical spectra of V2491 Cyg and V

UBV photometry of dwarf novae in the brightness minimum

International Nuclear Information System (INIS)

Voloshina, I.B.; Lyutyj, V.M.

1983-01-01

Photoelectric one-night observations of the dwarf novae SS Cyg at minimum light evidence for the existence of eclipses in this system at the moments of conjuctions. The orbital inclination of the system is estimated to be i approximately 70 deg C. The components of this system are low-massive (white and red dwarf stars) and low-luminous objects. As the optical luminosity of the dwarf novae at the minimum light is dependent on the accretion disk and hot spot at its periphery, where the substance jet run out from a nondegenerated component falls, eclipses should be associated with the disk and hot spot. The white dwarf star contributes greatly to the luminosity at the minimum light, but its eclipses are possible only at i approximately 90 deg

Laser systems for on-line laser ion sources

International Nuclear Information System (INIS)

Geppert, Christopher

2008-01-01

Since its initiation in the middle of the 1980s, the resonant ionization laser ion source has been established as a reliable and efficient on-line ion source for radioactive ion beams. In comparison to other on-line ion sources it comprises the advantages of high versatility for the elements to be ionized and of high selectivity and purity for the ion beam generated by resonant laser radiation. Dye laser systems have been the predominant and pioneering working horses for laser ion source applications up to recently, but the development of all-solid-state titanium:sapphire laser systems has nowadays initiated a significant evolution within this field. In this paper an overview of the ongoing developments will be given, which have contributed to the establishment of a number of new laser ion source facilities worldwide during the last five years.

The UBV Color Evolution of Classical and Symbiotic Novae

Directory of Open Access Journals (Sweden)

I. Hachisu

2015-02-01

Full Text Available We identified a general course of classical nova outbursts in the B − V vs. U − B diagram. It has been reported that novae show spectra similar to A–F supergiants near optical light maximum. However, they do not follow the supergiant sequence in the color-color diagram, neither the blackbody nor the main-sequence sequence. Instead, we found that novae evolve along a new sequence in the pre-maximum and near-maximum phases, which we call the nova-giant sequence. This sequence is parallel to but Δ(U − B ≈ −0.2 mag bluer than the supergiant sequence. After optical maximum, its color quickly evolves back blueward along the same nova-giant sequence and reaches the point of free-free emission (B − V = −0.03, U − B = −0.97 and stays there for a while, which is coincident with the intersection of the blackbody sequence and the nova-giant sequence. Then the color evolves leftward (blueward in B − V but almost constant in U − B due mainly to development of strong emission lines. This is the general course of nova outbursts in the color-color diagram, which is deduced from eight well-observed novae including various speed classes. For a nova with unknown extinction, we can determine a reliable value of the color excess by matching the observed track of the target nova with this general course. This is a new and convenient method for obtaining color excesses of classical novae. Using this method, we redetermined the color excesses of nineteen well-observed novae.

Navigated Pattern Laser System versus Single-Spot Laser System for Postoperative 360-Degree Laser Retinopexy.

Science.gov (United States)

Kulikov, Alexei N; Maltsev, Dmitrii S; Boiko, Ernest V

2016-01-01

Purpose . To compare three 360°-laser retinopexy (LRP) approaches (using navigated pattern laser system, single-spot slit-lamp (SL) laser delivery, and single-spot indirect ophthalmoscope (IO) laser delivery) in regard to procedure duration, procedural pain score, technical difficulties, and the ability to achieve surgical goals. Material and Methods . Eighty-six rhegmatogenous retinal detachment patients (86 eyes) were included in this prospective randomized study. The mean procedural time, procedural pain score (using 4-point Verbal Rating Scale), number of laser burns, and achievement of the surgical goals were compared between three groups (pattern LRP (Navilas® laser system), 36 patients; SL-LRP, 28 patients; and IO-LRP, 22 patients). Results . In the pattern LRP group, the amount of time needed for LRP and pain level were statistically significantly lower, whereas the number of applied laser burns was higher compared to those in the SL-LRP group and in the IO-LRP group. In the pattern LRP, SL-LRP, and IO-LRP groups, surgical goals were fully achieved in 28 (77.8%), 17 (60.7%), and 13 patients (59.1%), respectively ( p > 0.05). Conclusion . The navigated pattern approach allows improving the treatment time and pain in postoperative 360° LRP. Moreover, 360° pattern LRP is at least as effective in achieving the surgical goal as the conventional (slit-lamp or indirect ophthalmoscope) approaches with a single-spot laser.

The Radio Light Curve of the Gamma-Ray Nova in V407 CYG: Thermal Emission from the Ionized Symbiotic Envelope, Devoured from Within by the Nova Blast

Science.gov (United States)

Chomiuk, Laura; Krauss, Miriam I.; Rupen, Michael P.; Nelson, Thomas; Roy, Nirupam; Sokoloski, Jennifer L.; Mukai, Koji; Munari, Ulisse; Mioduszewski, Amy; Weston, Jeninfer;

V2487 Oph 1998: a post nova in an intermediate polar

Directory of Open Access Journals (Sweden)

Hernanz Margarita

2014-01-01

Full Text Available V2487 Oph (Nova Oph 1998 is a classical nova that exploded in 1998. XMM-Newton observations performed between 2 and 9 years after the explosion showed emission related to restablished accretion, and indicative of a magnetic white dwarf. The spectrum looks like that of a cataclysmic variable of the intermediate polar type. Anyway, we don’t have yet a definitive confirmation of the intermediate polar character, through determination of spin and orbital periods. Although it is not the first nova exploding in a magnetic white dwarf, it is always challenging to reach explosive conditions when a standard accretion disk can’t be formed, because of the magnetic field. In addition, V2487 Oph has been the first nova where a detection of X-rays - in the host binary system – has been reported prior to its eruption, in 1990 with the ROSAT satellite. V2487 Oph has been also detected in hard X-rays with INTEGRAL/IBIS and RXTE/PCA. Last but not least, V2487 Oph has been identified as a recurrent nova in 2008, since a prior eruption in 1900 has been reported through analysis of Harvard photographic plates. Therefore, it is expected to host a massive white dwarf and be a candidate for a type Ia supernova explosion. In a recent study of the progenitors of galactic novae, it has been emphasized that V2487 Oph is an important and interesting object, "intermediate" between the "standard" classical novae and other historical and well-known recurrent novae with shorter recurrence periods. It could be that in the end there’s a continuous distribution of recurrence periods, instead of the common understanding up to now that "classical" and "recurrent" novae were quite apart (with recurrence periods of more than 104 years and less than 100years - approximately - respectively. We present the results of our campaign of several observations with XMM-Newton. The consequences for the understanding of such a puzzling object are discussed.

New insights from a statistical analysis of IUE spectra of dwarf novae and nova-like stars. I - Inclination effects in lines and continua

Science.gov (United States)

La Dous, Constanze

1991-01-01

IUE observations of dwarf novae at maximum at quiescence and novalike objects at the high brightness state are analyzed for effects of the inclination angle on the emitted continuum and line radiation. A clear pattern in the continuum flux distribution is exhibited only by dwarf novae at maximum where some 80 percent of the non-double-eclipsing systems show essentially identical distributions. This result is not in disagreement with theoretical expectations. All classes of objects exhibit a clear, but in each case different, dependence of the line radiation on the inclination angle.

Laser program development at CEL-V: overview of recent experimental results

International Nuclear Information System (INIS)

Buresi, E.; Coutant, J.; Dautray, R.

1985-11-01

A significant effort has been made recently at CEL-V to improve laser facilities. OCTAL, the eight beam, 2 kJ laser, has been equipped with phosphate glass and KDP frequency tripling systems. PHEBUS, a two beam 20 kJ neodymium glass laser based on NOVA technology was defined, built and will be tested in early 1986 in close collaboration with Lawrence Livermore National laboratory. In the field of diagnostics, the development of soft X-ray emission analysis has been emphasized. Most of recent experimental results have been obtained at short wave-length (0.35 μm). They deal with: effect of non-uniform illumination, 2D hydrodynamics with either plane or spherical targets, and study of thermal transport inhibition

X-ray Modeling of Classical Novae

Science.gov (United States)

Nemeth, Peter

2010-01-01

It has been observed and theoretically supported in the last decade that the peak of the spectral energy distribution of classical novae gradually shifts to higher energies at constant bolometric luminosity after a nova event. For this reason, comprehensive evolutionary studies require spectral analysis in multiple spectral bands. After a nova explosion, the white dwarf can maintain stable surface hydrogen burning, the duration of which strongly correlates with the white dwarf mass. During this stage the peak of the luminosity is in the soft X-ray band (15 - 60 Angstroms). By extending the modeling range of TLUSTY/SYNSPEC, I analyse the luminosity and abundance evolution of classical novae. Model atoms required for this work were built using atomic data from NIST/ASD and TOPBASE. The accurate but incomplete set of energy levels and radiative transitions in NIST were completed with calculated data from TOPBASE. Synthetic spectra were then compared to observed data to derive stellar parameters. I show the capabilities and validity of this project on the example of V4743 Sgr. This nova was observed with both Chandra and XMM-Newton observatories and has already been modeled by several scientific groups (PHOENIX, TMAP).

Aprendizagens e novas tecnologias

Directory of Open Access Journals (Sweden)

Pedro Demo

2011-06-01

Full Text Available Pretendo aqui, muito preliminarmente, reunir alguns argumentos favoráveis à multiplicidade de oportunidades de aprender que o aluno pode encontrar hoje em ambientes de aprendizagem mediados por novas tecnologias. Centro-me principalmente na desconstrução de algumas resistências pedagógicas (EVANS, 2001 ainda persistentes entre nós como “transmissão de conteúdos”; agarramento a uma única teoria; fixação na aula instrucionista; extirpação/endeusamento de processos avaliativos, etc. Procuro ver, em um vasto âmbito de ofertas teóricas, componentes atualmente ressaltados na discussão tecnológica em vigor, com o objetivo de indicar oportunidades de reconstrução muito aproveitável de autores e clássicos, uma vez que aprender bem não foi algo inventado pelas novas tecnologias; sempre existiu e os grandes pedagogos tiveram consciência disso, insinuando infinitas maneiras de aprender bem (DEMO, 2008. As novas tecnologias proporcionam oportunidades ainda mais ampliadas, em meio também a enormes riscos e desacertos. O que menos interessa aqui é incidir em panaceias tecnológicas, bem a gosto do consumismo neoliberal. Interessa, porém, explorar novas oportunidades de aprendizagem, bem mais centradas na atividade dos alunos, flexíveis, motivadoras e capazes de sustentar processos de autoria e autonomia.

THE UNUSUALLY LUMINOUS EXTRAGALACTIC NOVA SN 2010U

International Nuclear Information System (INIS)

Czekala, Ian; Berger, E.; Chornock, R.; Marion, G. H.; Margutti, R.; Challis, P.; Pastorello, A.; Botticella, M. T.; Ergon, M.; Sollerman, J.; Smartt, S.; Vinkó, J.; Wheeler, J. C.

2013-01-01

We present observations of the unusual optical transient SN 2010U, including spectra taken 1.03 days to 15.3 days after maximum light that identify it as a fast and luminous Fe II type nova. Our multi-band light curve traces the fast decline (t 2 = 3.5 ± 0.3 days) from maximum light (M V = –10.2 ± 0.1 mag), placing SN 2010U in the top 0.5% of the most luminous novae ever observed. We find typical ejecta velocities of ≈1100 km s –1 and that SN 2010U shares many spectral and photometric characteristics with two other fast and luminous Fe II type novae, including Nova LMC 1991 and M31N-2007-11d. For the extreme luminosity of this nova, the maximum magnitude versus rate of decline relationship indicates a massive white dwarf (WD) progenitor with a low pre-outburst accretion rate. However, this prediction is in conflict with emerging theories of nova populations, which predict that luminous novae from massive WDs should preferentially exhibit an alternate spectral type (He/N) near maximum light.

A System for Exchanging Control and Status Messages in the NOvA Data Acquisition

International Nuclear Information System (INIS)

Biery, K.A.; Cooper, R.G.; Foulkes, S.C.; Guglielmo, G.M.; Piccoli, L.P.; Votava, M.E.V.; Fermilab

2007-01-01

In preparation for NOvA, a future neutrino experiment at Fermilab, we are developing a system for passing control and status messages in the data acquisition system. The DAQ system will consist of applications running on approximately 450 nodes. The message passing system will use a publish-subscribe model and will provide support for sending messages and receiving the associated replies. Additional features of the system include a layered architecture with custom APIs tailored to the needs of a DAQ system, the use of an open source messaging system for handling the reliable delivery of messages, the ability to send broadcasts to groups of applications, and APIs in Java, C++, and Python. Our choice for the open source system to deliver messages is EPICS. We will discuss the architecture of the system, our experience with EPICS, and preliminary test results

A System for Exchanging Control and Status Messages in the NOvA Data Acquisition

Energy Technology Data Exchange (ETDEWEB)

Biery, K.A.; Cooper, R.G.; Foulkes, S.C.; Guglielmo, G.M.; Piccoli, L.P.; Votava, M.E.V.; /Fermilab

2007-04-01

In preparation for NOvA, a future neutrino experiment at Fermilab, we are developing a system for passing control and status messages in the data acquisition system. The DAQ system will consist of applications running on approximately 450 nodes. The message passing system will use a publish-subscribe model and will provide support for sending messages and receiving the associated replies. Additional features of the system include a layered architecture with custom APIs tailored to the needs of a DAQ system, the use of an open source messaging system for handling the reliable delivery of messages, the ability to send broadcasts to groups of applications, and APIs in Java, C++, and Python. Our choice for the open source system to deliver messages is EPICS. We will discuss the architecture of the system, our experience with EPICS, and preliminary test results.

Province of Nova Scotia Electricity Marketplace Governance Committee First Interim Report

International Nuclear Information System (INIS)

2002-12-01

This report summarizes the group discussions of the Electricity Marketplace Governance Committee's (EMGC) over the past 6 months regarding the implementation of new rules for power competition in Nova Scotia's electricity market. Emphasis has been placed on external influences, defining the size and form of the short-term competitive portion of the Nova Scotia market, and a detailed consideration of the current transmission system and the changes needed to achieve a sustainable, world class energy sector that would enhance the quality of life for Nova Scotians. The report provides recommendations regarding how competition can be encouraged. The main drivers for electricity restructuring have been energy efficiency, risk-allocation, reliability, environmental impact, and consumer protection. The external influences on the Nova Scotia electricity market include: (1) economics of electricity restructuring, (2) the Federal Energy Regulatory Commission, (3) New Brunswick and electricity restructuring, and (4) Nova Scotia and the energy strategy. This report described the market scope and basic market model with reference to bilateral contract market, fully competitive wholesale pool market, and a single buyer market. The transmission issues discussed in this report included the importance of transmission, transmission tariff options, transmission services offered, design issues, and congestion management policies. The EMGC was directed to examine market design issues to accommodate an Open Access Transmission Tariff (OATT). As such, this report identifies some transmission issues that must be resolved to implement tariffs, and conditions of access to the transmission system and its impact on open access market design. The final report is expected to be available in March 2003

Laser Megajoule synchronization system

International Nuclear Information System (INIS)

Luttmann, M.; Pastor, J.F; Drouet, V.; Prat, M.; Raimbourg, J.; Adolf, A.

2011-01-01

This paper describes the synchronisation system under development on the Laser Megajoule (LMJ) in order to synchronize the laser quads on the target to better than 40 ps rms. Our architecture is based on a Timing System (TS) which delivers trigger signals with jitter down to 15 ps rms coupled with an ultra precision timing system with 5 ps rms jitter. In addition to TS, a sensor placed at the target chamber center measures the arrival times of the 3 omega nano joule laser pulses generated by front end shots. (authors)

Development of automatic laser welding system

International Nuclear Information System (INIS)

Ohwaki, Katsura

2002-01-01

Laser are a new production tool for high speed and low distortion welding and applications to automatic welding lines are increasing. IHI has long experience of laser processing for the preservation of nuclear power plants, welding of airplane engines and so on. Moreover, YAG laser oscillators and various kinds of hardware have been developed for laser welding and automation. Combining these welding technologies and laser hardware technologies produce the automatic laser welding system. In this paper, the component technologies are described, including combined optics intended to improve welding stability, laser oscillators, monitoring system, seam tracking system and so on. (author)

Copernicus observations of Nova Cygni 1975

Science.gov (United States)

Jenkins, E. B.; Snow, T. P.; Upson, W. L.; Anderson, R.; Starrfield, S. G.; Gallagher, J. S.; Friedjung, M.; Linsky, J. L.; Henry, R. C.; Moos, H. W.

1977-01-01

Near-ultraviolet radiation from Nova Cygni 1975 was detected by the Copernicus satellite on five occasions from 1975 September 1 to 1975 September 9. The nova was not seen in the UV after this date. The principal result was the observation of a broad emission feature from the Mg II doublet at 2800 A. The absence of strong UV radiation at shorter wavelengths suggests that these lines are produced by collisional excitation in the outer layers of an expanding shell with electron temperature of approximately 4000 K. The absence of observed emission lines from highly ionized species indicates that the amount of material with log T between 4.4 and 5.7 is less than 0.001 times that which produces the Mg II emission. The continuum flux in the near-UV decreased as the nova evolved, showing that the total luminosity decreased as the nova faded in the visible.

Nova target chamber decontamination study

International Nuclear Information System (INIS)

1979-05-01

An engineering study was performed to determine the most effective method for decontamination of the Nova target chamber. Manual and remote decontamination methods currently being used were surveyed. In addition, a concept that may not require in-situ decontamination was investigated. Based on the presently available information concerning material and system compatibility and particle penetration, it is recommended that a system of removable aluminum shields be considered. It is also recommended that a series of tests be performed to more precisely determine the vacuum compatibility and penetrability of other materials discussed in this report

Laser program. Annual report, 1978

International Nuclear Information System (INIS)

Monsler, M.J.; Jarman, B.D.

1979-03-01

An overview of the entire program is given. The overview previews the report, highlights progress in 1978, and summarizes the facilities and resources of the laser program. The Argus, Shiva, and Nova facilities are described. The theory of fusion target design is discussed along with specialized techniques of target fabrication

THE RADIO LIGHT CURVE OF THE GAMMA-RAY NOVA IN V407 CYG: THERMAL EMISSION FROM THE IONIZED SYMBIOTIC ENVELOPE, DEVOURED FROM WITHIN BY THE NOVA BLAST

Energy Technology Data Exchange (ETDEWEB)

Chomiuk, Laura; Krauss, Miriam I.; Rupen, Michael P.; Roy, Nirupam; Mioduszewski, Amy [National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801 (United States); Nelson, Thomas [School of Physics and Astronomy, University of Minnesota, 116 Church Street SE, Minneapolis, MN 55455 (United States); Sokoloski, Jennifer L.; Weston, Jennifer [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Mukai, Koji [CRESST and X-ray Astrophysics Laboratory, NASA/GSFC, Greenbelt, MD 20771 (United States); Munari, Ulisse [INAF Astronomical Observatory of Padova, I-36012 Asiago (VI) (Italy); O' Brien, Tim J. [Jodrell Bank Centre for Astrophysics, University of Manchester, Manchester M13 9PL (United Kingdom); Eyres, Stewart P. S. [Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE (United Kingdom); Bode, Michael F., E-mail: chomiuk@pa.msu.edu [Astrophysics Research Institute, Liverpool John Moores University, Twelve Quays House, Egerton Wharf, Birkenhead CH41 1LD (United Kingdom)

2012-12-20

We present multi-frequency radio observations of the 2010 nova event in the symbiotic binary V407 Cygni, obtained with the Karl G. Jansky Very Large Array (VLA) and spanning 1-45 GHz and 17-770 days following discovery. This nova-the first ever detected in gamma rays-shows a radio light curve dominated by the wind of the Mira giant companion, rather than the nova ejecta themselves. The radio luminosity grew as the wind became increasingly ionized by the nova outburst, and faded as the wind was violently heated from within by the nova shock. This study marks the first time that this physical mechanism has been shown to dominate the radio light curve of an astrophysical transient. We do not observe a thermal signature from the nova ejecta or synchrotron emission from the shock, due to the fact that these components were hidden behind the absorbing screen of the Mira wind. We estimate a mass-loss rate for the Mira wind of M-dot{sub w} approx. 10{sup -6} M{sub Sun} yr{sup -1}. We also present the only radio detection of V407 Cyg before the 2010 nova, gleaned from unpublished 1993 archival VLA data, which shows that the radio luminosity of the Mira wind varies by a factor of {approx}>20 even in quiescence. Although V407 Cyg likely hosts a massive accreting white dwarf, making it a candidate progenitor system for a Type Ia supernova, the dense and radially continuous circumbinary material surrounding V407 Cyg is inconsistent with observational constraints on the environments of most Type Ia supernovae.

Discovery of an old nova shell surrounding the cataclysmic variable V1315 Aql

Science.gov (United States)

Sahman, D. I.; Dhillon, V. S.; Littlefair, S. P.; Hallinan, G.

2018-04-01

Following our tentative discovery of a faint shell around V1315 Aql reported in Sahman et al. (2015), we undertook deep Hα imaging and intermediate-resolution spectroscopy of the shell. We find that the shell has its geometric centre located on V1315 Aql. The mass, spectral features and density of the shell are consistent with other nova shells, rather than planetary nebulae or supernova remnants. The radial velocity of the shell is consistent with the systemic velocity of V1315 Aql. We believe this evidence strongly suggests that the shell originates from an earlier nova event. This is the first nova shell discovered around a novalike, and supports the theory of nova-induced cycles in mass transfer rates (hibernation theory) first proposed by Shara et al. (1986).

Laser spark distribution and ignition system

Science.gov (United States)

Woodruff, Steven [Morgantown, WV; McIntyre, Dustin L [Morgantown, WV

2008-09-02

A laser spark distribution and ignition system that reduces the high power optical requirements for use in a laser ignition and distribution system allowing for the use of optical fibers for delivering the low peak energy pumping pulses to a laser amplifier or laser oscillator. An optical distributor distributes and delivers optical pumping energy from an optical pumping source to multiple combustion chambers incorporating laser oscillators or laser amplifiers for inducing a laser spark within a combustion chamber. The optical distributor preferably includes a single rotating mirror or lens which deflects the optical pumping energy from the axis of rotation and into a plurality of distinct optical fibers each connected to a respective laser media or amplifier coupled to an associated combustion chamber. The laser spark generators preferably produce a high peak power laser spark, from a single low power pulse. The laser spark distribution and ignition system has application in natural gas fueled reciprocating engines, turbine combustors, explosives and laser induced breakdown spectroscopy diagnostic sensors.

Laser fusion experiments, facilities and diagnostics at Lawrence Livermore Laboratory

International Nuclear Information System (INIS)

Ahlstrom, H.G.

1980-02-01

The progress of the LLL Laser Fusion Program to achieve high gain thermonuclear micro-explosions is discussed. Many experiments have been successfully performed and diagnosed using the large complex, 10-beam, 30 TW Shiva laser system. A 400 kJ design of the 20-beam Nova laser has been completed. The construction of the first phase of this facility has begun. New diagnostic instruments are described which provide one with new and improved resolution, information on laser absorption and scattering, thermal energy flow, suprathermal electrons and their effects, and final fuel conditions. Measurements were made on the absorption and Brillouin scattering for target irradiations at both 1.064 μm and 532 nm. These measurements confirm the expected increased absorption and reduced scattering at the shorter wavelength. Implosion experiments have been performed which have produced final fuel densities over the range of 10x to 100x liquid DT density

Imaging the Ejecta in Classical Novae

Science.gov (United States)

Linford, Justin

2016-10-01

A nova outburst results when sufficient mass accretes from a companion star onto the surface of a white dwarf, triggering a thermonuclear explosion. In classical novae the bulk of the emission comes from the warm, expanding ejecta. The prevailing theories assume that the explosion occurs as a single, spherically symmetric ejection event and predict a simple relationship between the white dwarf mass, the accretion rate, and the mass loss and energetics of the explosion. However, observations with modern instruments indicate that nova eruptions are far from simple. There is now evidence for multiple ejection events, common envelopes, non-spherical geometry, and even jet-like structures in the ejecta. Our ENova collaboration combines radio, mm, optical, and X-ray observations and detailed theoretical modelling to study the most common major explosions in the universe. Among our results so far are the direct demonstration of the importance of shocks in novae, including the detection of gamma-ray producing shocks in several sources, and the realization that multiple, long-lived outflows are much more common than previously assumed. Here we propose to continue these highly successful observations with coordinated detailed VLA radio interferometry and HST optical imaging and spectroscropy of several recent novae with substantial VLA monitoring already in progress.

On-Chip Laser-Power Delivery System for Dielectric Laser Accelerators

Science.gov (United States)

Hughes, Tyler W.; Tan, Si; Zhao, Zhexin; Sapra, Neil V.; Leedle, Kenneth J.; Deng, Huiyang; Miao, Yu; Black, Dylan S.; Solgaard, Olav; Harris, James S.; Vuckovic, Jelena; Byer, Robert L.; Fan, Shanhui; England, R. Joel; Lee, Yun Jo; Qi, Minghao

2018-05-01

We propose an on-chip optical-power delivery system for dielectric laser accelerators based on a fractal "tree-network" dielectric waveguide geometry. This system replaces experimentally demanding free-space manipulations of the driving laser beam with chip-integrated techniques based on precise nanofabrication, enabling access to orders-of-magnitude increases in the interaction length and total energy gain for these miniature accelerators. Based on computational modeling, in the relativistic regime, our laser delivery system is estimated to provide 21 keV of energy gain over an acceleration length of 192 μ m with a single laser input, corresponding to a 108-MV/m acceleration gradient. The system may achieve 1 MeV of energy gain over a distance of less than 1 cm by sequentially illuminating 49 identical structures. These findings are verified by detailed numerical simulation and modeling of the subcomponents, and we provide a discussion of the main constraints, challenges, and relevant parameters with regard to on-chip laser coupling for dielectric laser accelerators.

Plasma turbulence imaging using high-power laser Thomson scattering

Science.gov (United States)

Zweben, S. J.; Caird, J.; Davis, W.; Johnson, D. W.; Le Blanc, B. P.

2001-01-01

The two-dimensional (2D) structure of plasma density turbulence in a magnetically confined plasma can potentially be measured using a Thomson scattering system made from components of the Nova laser of Lawrence Livermore National Laboratory. For a plasma such as the National Spherical Torus Experiment at the Princeton Plasma Physics Laboratory, the laser would form an ≈10-cm-wide plane sheet beam passing vertically through the chamber across the magnetic field. The scattered light would be imaged by a charge coupled device camera viewing along the direction of the magnetic field. The laser energy required to make 2D images of density turbulence is in the range 1-3 kJ, which can potentially be obtained from a set of frequency-doubled Nd:glass amplifiers with diameters in the range of 208-315 mm. A laser pulse width of ⩽100 ns would be short enough to capture the highest frequency components of the expected density fluctuations.

Development of short pulse laser pumped x-ray lasers

International Nuclear Information System (INIS)

Dunn, J; Osterheld, A L; Hunter, J R; Shlyaptsev, V N

2000-01-01

X-ray lasers have been extensively studied around the world since the first laboratory demonstration on the Novette laser at LLNL in 1984 [l]. The characteristic properties of short wavelength, high monochromaticity, collimation and coherence make x-ray lasers useful for various applications. These include demonstrations of biological imaging within the water window, interferometry of laser plasmas and radiography of laser-heated surfaces. One of the critical issues has been the high power pump required to produce the inversion. The power scaling as a function of x-ray laser wavelength follows a -k4 to law. The shortest x-ray laser wavelength of ∼ 35 (angstrom) demonstrated for Ni-like All was at the limit of Nova laser capabilities. By requiring large, high power lasers such as Nova, the shot rate and total number of shots available have limited the rapid development of x-ray lasers and applications. In fact over the last fifteen years the main thrust has been to develop more efficient, higher repetition rate x-ray lasers that can be readily scaled to shorter wavelengths. The recent state of progress in the field can be found in references. The objective of the project was to develop a soft x-ray laser (XRL) pumped by a short pulse laser of a few joules. In effect to demonstrate a robust, worlung tabletop x-ray laser at LLNL for the first time. The transient collisional scheme as proposed by Shlyaptsev et al [8, 9] was the candidate x-ray laser for study. The successful endeavour of any scientific investigation is often based upon prudent early decisions and the choice of this scheme was both sound and fruitful. It had been demonstrated very recently for Ne-like Ti at 326 A using a small tabletop laser [10] but had not yet reached its full potential. We chose this scheme for several reasons: (a) it was a collisional-type x-ray laser which has been historically the most robust; (b) it had the promise of high efficiency and low energy threshold for lasing; (c) the

CO laser angioplasty system: efficacy of manipulatable laser angioscope catheter

Science.gov (United States)

Arai, Tsunenori; Kikuchi, Makoto; Mizuno, Kyoichi; Sakurada, Masami; Miyamoto, Akira; Arakawa, Koh; Kurita, Akira; Nakamura, Haruo; Takeuchi, Kiyoshi; Utsumi, Atsushi; Akai, Yoshiro

1992-08-01

A percutaneous transluminal coronary angioplasty system using a unique combination of CO laser (5 micrometers ) and As-S infrared glass fiber under the guidance of a manipulatable laser angioscope catheter is described. The ablation and guidance functions of this system are evaluated. The angioplasty treatment procedure under angioscope guidance was studied by in vitro model experiment and in vivo animal experiment. The whole angioplasty system is newly developed. That is, a transportable compact medical CO laser device which can emit up to 10 W, a 5 F manipulatable laser angioscope catheter, a thin CO laser cable of which the diameter is 0.6 mm, an angioscope imaging system for laser ablation guidance, and a system controller were developed. Anesthetized adult mongrel dogs (n equals 5) with an artificial complete occlusion in the femoral artery and an artificial human vessel model including occluded or stenotic coronary artery were used. The manipulatability of the catheter was drastically improved (both rotation and bending), therefore, precise control of ablation to expand stenosis was obtained. A 90% artificial stenosis made of human yellow plaque in 4.0 mm diameter in the vessel was expanded to 70% stenosis by repetitive CO laser ablations of which total energy was 220 J. All procedures were performed and controlled under angioscope visualization.

National Ignition Facility system design requirements Laser System SDR002

International Nuclear Information System (INIS)

Larson, D.W.; Bowers, J.M.; Bliss, E.S.; Karpenko, V.P.; English, E.

1996-01-01

This System Design Requirement document establishes the performance, design, development, and test requirements for the NIP Laser System. The Laser System generates and delivers high-power optical pulses to the target chamber, and is composed of all optical puke creating and transport elements from Puke Generation through Final Optics as well as the special equipment that supports, energizes and controls them. The Laser System consists of the following WBS elements: 1.3 Laser System 1.4 Beam Transport System 1.6 Optical Components 1.7 Laser Control 1.8.7 Final Optics

Nucleosynthesis in nova outbursts

International Nuclear Information System (INIS)

Iliadis, C.; Azuma, R.E.; Buchmann, L.

1994-02-01

Astronomical observations have shown that He, CNO material and/or heavy elements are considerably enriched in certain nova ejecta relative to solar matter. The heavy element enrichments can be explained by the dredge-up of matter from an underlying ONeMg white dwarf and subsequent redistribution of the material by the rp-process. The proton capture reactions on 32 S and 36 A r important for hydrogen burning during nova outbursts have been measured experimentally. The derived stellar reaction rates have been incorporated into large-scale network calculations and the astrophysical consequences are discussed. (author)

Effect of amplifier component maintenance on laser system availability and reliability for the US National Ignition Facility

International Nuclear Information System (INIS)

Erlandson, A.C.; Lambert, H.; Zapata, L.E.

1996-12-01

We have analyzed the availability and reliability of the flashlamp-pumped, Nd:glass amplifiers that, as a part of a laser now being designed for future experiments, in inertial confinement fusion (ICF), will be used in the National Ignition Facility (NIF). Clearly , in order for large ICF systems such as the NIF to operate effectively as a whole, all components must meet demanding availability and reliability requirements. Accordingly, the NIF amplifiers can achieve high reliability and availability by using reliable parts, and by using a cassette-based maintenance design that allows most key amplifier parts to be 1744 replaced within a few hours. In this way, parts that degrade slowly, as the laser slabs, silver reflectors, and blastshields can be expected to do, based on previous experience, can be replaced either between shots or during scheduled maintenance periods, with no effect on availability or reliability. In contrast, parts that fail rapidly, such as the flashlamps, can and do cause unavailability or unreliability. Our analysis demonstrates that the amplifiers for the NIF will meet availability and reliability goals, respectively, of 99.8% and 99.4%, provided that the 7680 NIF flashlamps in NIF have failure rates of less than, or equal to, those experienced on Nova, a 5000-lamp laser at Lawrence Livermore National Laboratory (LLNL)

Laser surveillance system (LASSY)

International Nuclear Information System (INIS)

Boeck, H.

1991-09-01

Laser Surveillance System (LASSY) is a beam of laser light which scans a plane above the water or under-water in a spent-fuel pond. The system can detect different objects and estimates its coordinates and distance as well. LASSY can operate in stand-alone configuration or in combination with a video surveillance to trigger signal to a videorecorder. The recorded information on LASSY computer's disk comprises date, time, start and stop angle of detected alarm, the size of the disturbance indicated in number of deviated points and some other information. The information given by the laser system cannot be fully substituted by TV camera pictures since the scanning beam creates a horizontal surveillance plan. The engineered prototype laser system long-term field test has been carried out in Soluggia (Italy) and has shown its feasibility and reliability under the conditions of real spent fuel storage pond. The verification of the alarm table on the LASSY computer with the recorded video pictures of TV surveillance system confirmed that all alarm situations have been detected. 5 refs

Aurora laser optical system

International Nuclear Information System (INIS)

Hanlon, J.A.; McLeod, J.

1987-01-01

Aurora is the Los Alamos short-pulse high-power krypton fluoride laser system. It is primarily an end-to-end technology demonstration prototype for large-scale UV laser systems of interest for short-wavelength inertial confinement fusion (ICF) investigations. The system is designed to employ optical angular multiplexing and aerial amplification by electron-beam-driven KrF laser amplifiers to deliver to ICF targets a stack of pulses with a duration of 5 ns containing several kilojoules at a wavelength of 248 nm. A program of high-energy density plasma physics investigations is now planned, and a sophisticated target chamber was constructed. The authors describe the design of the optical system for Aurora and report its status. This optical system was designed and is being constructed in two phases. The first phase carries only through the amplifier train and does not include a target chamber or any demultiplexing. Installation should be complete, and some performance results should be available. The second phase provides demultiplexing and carries the laser light to target. The complete design is reported

Quasi-periodic luminosity variations in dwarf novae

International Nuclear Information System (INIS)

Robinson, E.L.; Nather, R.E.

1979-01-01

We have identified quasi-periodic oscillations in the light curves of five dwarf novae--U Gem, SS Cyg, RU Peg, KT Per, and VW Hyi-- and in the light curve of the quasi-periodic X-ray source Sco X-1. The mean periods of the quasi-periodic oscillations range from 32 s in SS Cyg to 147 s in KT Per and 165 s in Sco X-l. Their amplitudes are typically 0.005--0.0l mag. The properties of the quasi-periodic oscillations are represented well by a second-order autoregressive process. Use of this representation shows that the length of time over which the quasi-periodic oscillations maintain coherence is very short, typically 3--5 cycles of the oscillations. Thus the quasi-periodic oscillations can be distinguished from the short-period coherent oscillations in dwarf novae, which are usually interpreted as white dwarf pulsations, because t the periods of the quasi-periodic oscillations are 3--4 times longer and their coherence time is much shorter. The quasi-periodic oscillations occur in dwarf novae only during their eruptions and occur in Sco X-l only when the system is bright. The presence of the oscillations does not depend on the subclass to which a dwarf nova belongs or on the morphology of the individual eruptions. We argue that their short periods, their short coherence times, and their presence in Sco X-l require that the quasi-periodic oscillations be produced by the accretion disk, and not by the stars or by the boundary between the a accretion disk and its central star

Time-Dependent Dust Formation in Novae

Directory of Open Access Journals (Sweden)

Kyung-Won Suh

1991-06-01

Full Text Available The dust formation processes in novae are investigated with close attention to recent infrared observations. Using mainly the classical nucleation theory, we have calculated the time scales of dust formation and growth in the environments of novae. Those time scales roughly resemble the typical observations. We have classified the dust-forming novae into three classes according to their explosion properties and the thermodynamic properties of dust grains. Oxygen grains from much later than carbon grains because of their thermodynamic properties. The effect of grain formation to the efficiency of stellar winds to drive the material outward is tested with newly obtained Planck mean values of dust grains.

Recent laser experiments on the Aurora KrF/ICF laser system

International Nuclear Information System (INIS)

Turner, T.P.; Jones, J.E.; Czuchlewski, S.J.; Watt, R.G.; Thomas, S.J.; Kang, M.; Tallman, C.R.; Mack, J.M.; Figueira, J.F.

1990-01-01

The Aurora KrF/ICF Laser Facility at Los Alamos is operational at the kilojoule-level for both laser and target experiments. We report on recent laser experiments on the system and resulting system improvements. 3 refs., 4 figs

Enquête de satisfaction Novae

CERN Multimedia

2014-01-01

Novae lance une enquête de satisfaction auprès de ses clients. Vous pouvez accéder au questionnaire au sujet des trois restaurants d’entreprise du CERN en utilisant le lien et les codes ci-dessous. Le délai de réponse est fixé au jeudi 29 mai.   https://survey.mis-trend.ch/NOVAE Voici les codes à introduire (en respectant la casse) pour entrer dans le questionnaire, selon le site : CERN Restaurant n°1 : CERN114 CERN Restaurant n°2 : CERN214 CERN Restaurant n°3 : CERN314   Nous attirons votre attention sur le fait que tout questionnaire rempli sera validé. Nous vous prions donc de ne pas utiliser ce lien pour tester le questionnaire. Merci d’avance pour votre collaboration. L'équipe Novae

Infrared photometry of the nova-like system IX Velorum (= CPD -4801577)

International Nuclear Information System (INIS)

Haug, Karlheinz

1988-01-01

Continuous IR photometry of the UX UMa-type nova-like system IX Velorum reveals phase-correlated light variations in JHK filter bands with an amplitude of about O m .06. From a periodogram analysis an orbital period of P = 0.1939 ± 0.0001 day is determined. Physical reasons for the observed IR light variability are discussed. Model light curve calculations demonstrate that the observed light curves can be interpreted by a superposition of ellipsoidal light variations and asymmetric light distribution on the surface of the secondary component owing to illumination from the disc. The observation of different heights of the two light maxima might be an indication for an additional orbital light variation due to the changing aspect of the disc and/or bright spot region. (author)

On Presolar Stardust Grains from CO Classical Novae

Science.gov (United States)

Iliadis, Christian; Downen, Lori N.; José, Jordi; Nittler, Larry R.; Starrfield, Sumner

2018-03-01

About 30%–40% of classical novae produce dust 20–100 days after the outburst, but no presolar stardust grains from classical novae have been unambiguously identified yet. Although several studies claimed a nova paternity for certain grains, the measured and simulated isotopic ratios could only be reconciled, assuming that the grains condensed after the nova ejecta mixed with a much larger amount of close-to-solar matter. However, the source and mechanism of this potential post-explosion dilution of the ejecta remains a mystery. A major problem with previous studies is the small number of simulations performed and the implied poor exploration of the large nova parameter space. We report the results of a different strategy, based on a Monte Carlo technique, that involves the random sampling over the most important nova model parameters: the white dwarf composition; the mixing of the outer white dwarf layers with the accreted material before the explosion; the peak temperature and density; the explosion timescales; and the possible dilution of the ejecta after the outburst. We discuss and take into account the systematic uncertainties for both the presolar grain measurements and the simulation results. Only those simulations that are consistent with all measured isotopic ratios of a given grain are accepted for further analysis. We also present the numerical results of the model parameters. We identify 18 presolar grains with measured isotopic signatures consistent with a CO nova origin, without assuming any dilution of the ejecta. Among these, the grains G270_2, M11-334-2, G278, M11-347-4, M11-151-4, and Ag26 have the highest probability of a CO nova paternity.

Some characteristics of isotopic separation laser systems

International Nuclear Information System (INIS)

Pochon, E.

1988-01-01

The principle of Laser Isotope Separation (LIS) is simple and based on either selective electronic photoexcitation and photoionization of atomic vapor, or selective vibrational photoexcitation and photodissociation of molecules in the gas phase. These processes, respectively called SILVA (AVLIS) and SILMO (MLIS) in France, both use specific laser systems with wavelengths spanning from infrared to ultraviolet. This article describes briefly some of the characteristics of a SILVA laser system. Following a three-step process, a SILVA laser system is based on dye copper vapor lasers. The pulse dye lasers provide the tunable laser light and are optically pumped by copper vapor laser operating at high repetition rates. In order to meet plant laser system requirements, the main improvements under way relate to copper vapor laser devices the power capability, efficiency, reliability and lifetime of which have to be increased. 1 fig

Solid state lasers II; Proceedings of the Meeting, Los Angeles, CA, Jan. 24, 25, 1991

International Nuclear Information System (INIS)

Dube, G.

1991-01-01

Topics presented include an upgrade of the LLNL Nova laser for inertial confinement fusion, the design and energy characteristics of a multisegment glass-disk amplifier, a wavemeter for tuning solid state lasers, and the fabrication of laser materials by laser-heated pedestal growth. Also presented are the suppression of relaxation oscillations in flash-pumped 2-micron lasers, diode pumping of tunable Cr-doped lasers, 2D periodic structures in a solid state laser resonator, and single-frequency solid state lasers and amplifiers

Outbursts of symbiotic novae

International Nuclear Information System (INIS)

Kenyon, S.J.; Truran, J.W.

1983-01-01

We discuss possible conditions under which thermonuclear burning episodes in the hydrogen-rich envelopes of accreting white dwarfs give rise to outbursts similar in nature to those observed in the symbiotic stars AG Peg, RT Ser, RR Tel, AS 239, V1016 Cyg, V1329 Cyg, and HM Sge. In principle, thermonuclear runaways involving low-luminosity white dwarfs accreting matter at low rates produce configurations that evolve into A--F supergiants at maximum visual light and which resemble the outbursts of RR Tel, RT Ser, and AG peg. Very weak, nondegenerage hydrogen shell flashes on white dwarfs accreting matter at high rates (M> or approx. =10 -8 M/sub sun/ yr -1 ) do not produce cool supergiants at maximum, and may explain the outbursts in V1016 Cyg, V1329 Cyg, and HM Sge. The low accretion rates demanded for systems developing strong hydrogen shell flashes on low-luminsoity white dwarfs are not compatible with observations of ''normal'' quiescent symbiotic stars. The extremely slow outbursts of symbiotic novae appear to be typical of accreting white dwarfs in wide binaries, which suggests that the outbursts of classical novae may be accelerated by the interaction of the expanding white dwarf envelope with its close binary companion

NUCLEAR MIXING METERS FOR CLASSICAL NOVAE

Energy Technology Data Exchange (ETDEWEB)

Kelly, Keegan J.; Iliadis, Christian; Downen, Lori; Champagne, Art [Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3255 (United States); José, Jordi [Departament de Física i Enginyeria Nuclear, EUETIB, Universitat Politècnica de Catalunya, E-08036 Barcelona (Spain)

2013-11-10

Classical novae are caused by mass transfer episodes from a main-sequence star onto a white dwarf via Roche lobe overflow. This material possesses angular momentum and forms an accretion disk around the white dwarf. Ultimately, a fraction of this material spirals in and piles up on the white dwarf surface under electron-degenerate conditions. The subsequently occurring thermonuclear runaway reaches hundreds of megakelvin and explosively ejects matter into the interstellar medium. The exact peak temperature strongly depends on the underlying white dwarf mass, the accreted mass and metallicity, and the initial white dwarf luminosity. Observations of elemental abundance enrichments in these classical nova events imply that the ejected matter consists not only of processed solar material from the main-sequence partner but also of material from the outer layers of the underlying white dwarf. This indicates that white dwarf and accreted matter mix prior to the thermonuclear runaway. The processes by which this mixing occurs require further investigation to be understood. In this work, we analyze elemental abundances ejected from hydrodynamic nova models in search of elemental abundance ratios that are useful indicators of the total amount of mixing. We identify the abundance ratios ΣCNO/H, Ne/H, Mg/H, Al/H, and Si/H as useful mixing meters in ONe novae. The impact of thermonuclear reaction rate uncertainties on the mixing meters is investigated using Monte Carlo post-processing network calculations with temperature-density evolutions of all mass zones computed by the hydrodynamic models. We find that the current uncertainties in the {sup 30}P(p, γ){sup 31}S rate influence the Si/H abundance ratio, but overall the mixing meters found here are robust against nuclear physics uncertainties. A comparison of our results with observations of ONe novae provides strong constraints for classical nova models.

Multi-terawatt fusion laser systems

International Nuclear Information System (INIS)

Holzrichter, J.F.

1993-01-01

The evolution of laser fusion systems started with a description of the basic principles of the laser in 1959, then a physical demonstration showing 1000 Watts of peak optical power in 1961 to the present systems that deliver 10 14 watts of peak optical power, are presented. Physical limits to large systems are reviewed: thermal limits, material stress limits, structural limits and stability, parasitic coupling, measurement precision and diagnostics. The various steps of the fusion laser-system development process are then discussed through an historical presentation. 3 figs., 8 refs

Nucleosynthesis in nova outbursts

Energy Technology Data Exchange (ETDEWEB)

Iliadis, C [TRIUMF, Vancouver, BC (Canada); [Univ. of Toronto, McLennan Physical Labs., Toronto, ON (Canada); Azuma, R E [Univ. of Toronto, McLennan Physical Lab., Toronto, ON (Canada); Buchmann, L [TRIUMF, Vancouver, BC (Canada); and others

1994-02-01

Astronomical observations have shown that He, CNO material and/or heavy elements are considerably enriched in certain nova ejecta relative to solar matter. The heavy element enrichments can be explained by the dredge-up of matter from an underlying ONeMg white dwarf and subsequent redistribution of the material by the rp-process. The proton capture reactions on 32{sup S} and 36{sup A}r important for hydrogen burning during nova outbursts have been measured experimentally. The derived stellar reaction rates have been incorporated into large-scale network calculations and the astrophysical consequences are discussed. (author) 17 refs., 2 figs.

Coherent laser vision system

International Nuclear Information System (INIS)

Sebastion, R.L.

1995-01-01

The Coherent Laser Vision System (CLVS) is being developed to provide precision real-time 3D world views to support site characterization and robotic operations and during facilities Decontamination and Decommissioning. Autonomous or semiautonomous robotic operations requires an accurate, up-to-date 3D world view. Existing technologies for real-time 3D imaging, such as AM laser radar, have limited accuracy at significant ranges and have variability in range estimates caused by lighting or surface shading. Recent advances in fiber optic component technology and digital processing components have enabled the development of a new 3D vision system based upon a fiber optic FMCW coherent laser radar. The approach includes a compact scanner with no-moving parts capable of randomly addressing all pixels. The system maintains the immunity to lighting and surface shading conditions which is characteristic to coherent laser radar. The random pixel addressability allows concentration of scanning and processing on the active areas of a scene, as is done by the human eye-brain system

Coherent laser vision system

Energy Technology Data Exchange (ETDEWEB)

Sebastion, R.L. [Coleman Research Corp., Springfield, VA (United States)

1995-10-01

The Coherent Laser Vision System (CLVS) is being developed to provide precision real-time 3D world views to support site characterization and robotic operations and during facilities Decontamination and Decommissioning. Autonomous or semiautonomous robotic operations requires an accurate, up-to-date 3D world view. Existing technologies for real-time 3D imaging, such as AM laser radar, have limited accuracy at significant ranges and have variability in range estimates caused by lighting or surface shading. Recent advances in fiber optic component technology and digital processing components have enabled the development of a new 3D vision system based upon a fiber optic FMCW coherent laser radar. The approach includes a compact scanner with no-moving parts capable of randomly addressing all pixels. The system maintains the immunity to lighting and surface shading conditions which is characteristic to coherent laser radar. The random pixel addressability allows concentration of scanning and processing on the active areas of a scene, as is done by the human eye-brain system.

Laser engineering of microbial systems

Science.gov (United States)

Yusupov, V. I.; Gorlenko, M. V.; Cheptsov, V. S.; Minaev, N. V.; Churbanova, E. S.; Zhigarkov, V. S.; Chutko, E. A.; Evlashin, S. A.; Chichkov, B. N.; Bagratashvili, V. N.

2018-06-01

A technology of laser engineering of microbial systems (LEMS) based on the method of laser-induced transfer of heterogeneous mixtures containing microorganisms (laser bioprinting) is described. This technology involves laser printing of soil microparticles by focusing near-infrared laser pulses on a specially prepared gel/soil mixture spread onto a gold-coated glass plate. The optimal range of laser energies from the point of view of the formation of stable jets and droplets with minimal negative impact on living systems of giant accelerations, laser pulse irradiation, and Au nanoparticles was found. Microsamples of soil were printed on glucose-peptone-yeast agar plates to estimate the LEMS process influence on structural and morphological microbial diversity. The obtained results were compared with traditionally treated soil samples. It was shown that LEMS technology allows significantly increasing the biodiversity of printed organisms and is effective for isolating rare or unculturable microorganisms.

SN 2010U: A LUMINOUS NOVA IN NGC 4214

International Nuclear Information System (INIS)

Humphreys, Roberta M.; Helton, L. Andrew; Prieto, Jose L.; Rosenfield, Philip; Williams, Benjamin; Murphy, Jeremiah; Dalcanton, Julianne; Gilbert, Karoline; Kochanek, Christopher S.; Stanek, K. Z.; Khan, Rubab; Szczygiel, Dorota; Mogren, Karen; Fesen, Robert A.; Milisavljevic, Dan

2010-01-01

The luminosity, light curve, post-maximum spectrum, and lack of a progenitor on deep pre-outburst images suggest that SN 2010U was a luminous, fast nova. Its outburst magnitude is consistent with that for a fast nova using the maximum magnitude-rate of decline relationship for classical novae.

Dynamic analysis of the Nova Target Chamber to assess alignment errors due to ambient noise

International Nuclear Information System (INIS)

McCallen, D.B.; Murray, R.C.

1984-01-01

We performed a study to determine the dynamic behavior of the Nova Target Chamber. We conducted a free vibration analysis to determine the natural frequencies of vibration and the corresponding modeshapes of the target chamber. Utilizing the free vibration results, we performed forced vibration analysis to predict the displacements of the chamber due to ambient vibration. The input support motion for the forced vibration analysis was defined by a white noise acceleration spectrum which was based on previous measurements of ground noise near the Nova site. A special purpose computer program was prepared to process the results of the forced vibration analysis. The program yields distances by which the lines of sight of the various laser beams miss the target as a result of ambient vibrations. We also performed additional estimates of miss distance to provide bounds on the results. A description of the finite element model of the chamber, the input spectrum, and the results of the analyses are included

Nova Aquilae 1982: the nature of its dust

International Nuclear Information System (INIS)

Longmore, A.J.; Williams, P.M.

1984-01-01

Infrared photometric measurements of Nova Aquilae 1982, covering a period from 37 to 261 days after its discovery, have been obtained. Thermal emission was present even from the first observation. The observations show that the conventional picture of dust forming in the nova ejecta does not apply in this case, and suggest that a re-examination of the infrared modelling of earlier novae would be worthwhile. (U.K.)

Dust formation and ionization in novae

International Nuclear Information System (INIS)

Yamamoto, Tetsuo; Sato, Shuji; Nariai, Kyoji.

1979-01-01

In order to explain the fact that some novae show the increase of infrared radiation indicating the formation of circumstellar dust grains while some others do not, the theory that the formation of dust in the circumstellar envelope of a nova depends on the intensity of ultraviolet radiation from a central star has been presented. It is known that the central star of a nova emits radiation at nearly constant rate, and its effective temperature rises. It was concluded that the novae with higher emission than a certain value are the poor candidates for dust formation because the whole envelope is ionized before dust is formed. But this conclusion is misleading. The evolution of the ultraviolet radiation emanating from a central star is summarized. The condensation of grains is possible when the partial pressure of the vapor, from which the grains are formed, becomes higher than the saturation vapor pressure. The temperature of grains can be estimated by equating the radiations absorbed and emitted. The grains evaporate if the grain temperature is higher than the condensation temperature. The formation of a Stroemgren sphere in the exploding envelope of a nova is discussed. For the formation of grains, it is necessary that temperature drops below the condensation temperature before the whole envelope is ionized. Hence dust grains do not grow if the grain temperature at a phase is higher than the condensation temperature. (Kako, I.)

The electrification of Nova Scotia, 1884--1973: Technological modernization as a response to regional disparity

Science.gov (United States)

King, Lionel Bradley

This dissertation investigates local attempts to use technology as a force for regional rehabilitation in the economically-depressed Maritime region of Canada. At the time of Confederation in 1867, the Maritime province of Nova Scotia was prosperous, progressive, and cultured. By the end of the 1910s, the province had entered a long period of economic and social decline. Recent historiography has shown that, far from passively accepting their fate, Nova Scotians and other Maritimers, actively resisted marginalization with political, cultural, or social action. The thesis expands upon that literature by exploring technology-based strategies of provincial rehabilitation using Thomas P. Hughes's systems perspective and David E. Nye's semiotic approach. In doing so, it applies methods from the social constructivist school of the history of technology to the larger concerns of Maritime Canadian historiography. In large part, the North American culture of technology determined the ways in which Nova Scotians applied technological solutions to provincial concerns. Technology has long been central to the Western idea of progress. As the "high technology" of the late nineteenth and early twentieth centuries, electricity reinforced that view: its ephemeral nature and silent efficiency led people to endow it with transformative, even mystical, powers. As a result, Nova Scotians, adopted a program of electrical modernization in the late 1910s as a remedy for regional disparity. The Nova Scotia government's first step was the creation of an Ontario-style hydroelectric commission designed to bring order to the province's fragmented and inefficient electrical network. Over the next few decades, the Nova Scotia Power Commission implemented rural electrification, home modernization, and regional system-building models that had already proven successful in Ontario and the United States. The system-building philosophies behind these programs were adapted to local conditions and

The Theory of Random Laser Systems

International Nuclear Information System (INIS)

Xunya Jiang

2002-01-01

Studies of random laser systems are a new direction with promising potential applications and theoretical interest. The research is based on the theories of localization and laser physics. So far, the research shows that there are random lasing modes inside the systems which is quite different from the common laser systems. From the properties of the random lasing modes, they can understand the phenomena observed in the experiments, such as multi-peak and anisotropic spectrum, lasing mode number saturation, mode competition and dynamic processes, etc. To summarize, this dissertation has contributed the following in the study of random laser systems: (1) by comparing the Lamb theory with the Letokhov theory, the general formulas of the threshold length or gain of random laser systems were obtained; (2) they pointed out the vital weakness of previous time-independent methods in random laser research; (3) a new model which includes the FDTD method and the semi-classical laser theory. The solutions of this model provided an explanation of the experimental results of multi-peak and anisotropic emission spectra, predicted the saturation of lasing modes number and the length of localized lasing modes; (4) theoretical (Lamb theory) and numerical (FDTD and transfer-matrix calculation) studies of the origin of localized lasing modes in the random laser systems; and (5) proposal of using random lasing modes as a new path to study wave localization in random systems and prediction of the lasing threshold discontinuity at mobility edge

ON THE SPECTROSCOPIC CLASSES OF NOVAE IN M33

International Nuclear Information System (INIS)

Shafter, A. W.; Darnley, M. J.; Bode, M. F.; Ciardullo, R.

2012-01-01

We report the initial results from an ongoing multi-year spectroscopic survey of novae in M33. The survey resulted in the spectroscopic classification of six novae (M33N 2006-09a, 2007-09a, 2009-01a, 2010-10a, 2010-11a, and 2011-12a) and a determination of rates of decline (t 2 times) for four of them (2006-09a, 2007-09a, 2009-01a, and 2010-10a). When these data are combined with existing spectroscopic data for two additional M33 novae (2003-09a and 2008-02a), we find that five of the eight novae with available spectroscopic class appear to be members of either the He/N or Fe IIb (hybrid) classes, with only two clear members of the Fe II spectroscopic class. This initial finding is very different from what would be expected based on the results for M31 and the Galaxy where Fe II novae dominate, and the He/N and Fe IIb classes together make up only ∼20% of the total. It is plausible that the increased fraction of He/N and Fe IIb novae observed in M33 thus far may be the result of the younger stellar population that dominates this galaxy, which is expected to produce novae that harbor generally more massive white dwarfs than those typically associated with novae in M31 or the Milky Way.

The GEO 600 laser system

CERN Document Server

Zawischa, I; Danzmann, K; Fallnich, C; Heurs, M; Nagano, S; Quetschke, V; Welling, H; Willke, B

2002-01-01

Interferometric gravitational wave detectors require high optical power, single frequency lasers with very good beam quality and high amplitude and frequency stability as well as high long-term reliability as input light source. For GEO 600 a laser system with these properties is realized by a stable planar, longitudinally pumped 12 W Nd:YAG rod laser which is injection-locked to a monolithic 800 mW Nd:YAG non-planar ring oscillator. Frequency control signals from the mode cleaners are fed to the actuators of the non-planar ring oscillator which determines the frequency stability of the system. The system power stabilization acts on the slave laser pump diodes which have the largest influence on the output power. In order to gain more output power, a combined Nd:YAG-Nd:YVO sub 4 system is scaled to more than 22 W.

Silicon switch development for optical pulse generation in fusion lasers at Lawrence Livermore National Laboratory

International Nuclear Information System (INIS)

Wilcox, R.B.

1983-01-01

We have been developing a silicon photoconductive switch for use as a Pockels cell driver in the pulse generation systems of the fusion lasers Nova and Novette. The objective has been to make 10 kV switches repeatably and which are reliable on an operating system. We found that nonlinear phenomena in nearly intrinsic silicon caused excessive conduction at high voltage resulting in breakdown. Our experiments with doped material show that this problem can be eliminated, resulting in useful devices

ISOLDE gets a new laser system

CERN Multimedia

Anaïs Schaeffer

2011-01-01

It's action stations at ISOLDE, the On-Line Isotope Mass Separator at CERN. The Laboratory is preparing to add a second laser ion source system to its arsenal. By alternating between two laser systems, the ISOLDE team will be able to switch from one type of beam to another in record time.   Bruce Marsh, from the EN-STI Group, with one of the lasers from ISOLDE's current system. The first laser source for producing radioactive ion beams (see box) was installed in the ISOLDE hall in the 1990s. This method, which was highly innovative for its time, has since been adopted by several laboratories all over the world. "This laser system allows us to control the ionisation wavelength with precision and thus to select specific atoms in order to produce very pure radioactive ion beams," explains Valentin Fedosseev of the EN Department. "These beams are then used for various experiments, in nuclear astrophysics and biology, for example. With two laser systems we will be able to do ...

TV photometry of the Nova Cygni 1975 (V1500 Cyg)

International Nuclear Information System (INIS)

Pavlenko, E.P.

1983-01-01

About 1800 TV pictures of Nova Cygni 1975 during 60 hours were obtained in 1979-1980 at the Crimean Astrophysical observatory. The observations were carried out in V and sometimes - similtaneously in B and V colour systems. The period of brightness Variations 0sUp(d).279226 remains constant after it has stabilized in 1978, but the amplitude and mean brightness of the individual light curves change from cycle to cycle. The mean light curves are asymmetrical. The depth of primary and secondary minima is sporadically increasing from year to year and reached 1sup(m).2 in 1980. The mean curves obtained in V system in 1980 and in continuum in 1976-1977 are similar. It is supposed that 6,7-hour varia. tions of brightness appear as a resUlt of partial eclipses in close binary system Nova Cygni with orbit inclination i=60 deg

Characterisation and application of NovaFiber lignin

NARCIS (Netherlands)

Gosselink, R.J.A.; Snijder, M.H.B.; Kranenbarg, A.; Keijsers, E.R.P.; Jong, de E.; Stigsson, L.L.

2004-01-01

Sulphur-free lignin coming from a novel alkaline-pulping process called NovaFiber, which has been developed by KIRAM AB, has been characterised and evaluated for potential applications. A Kraft lignin has been used for comparison. Considering the characterisation results of a NovaFiber softwood and

Recent Evolution of the Offline Computing Model of the NOvA Experiment

Science.gov (United States)

Habig, Alec; Norman, A.

2015-12-01

The NOvA experiment at Fermilab is a long-baseline neutrino experiment designed to study νe appearance in a νμ beam. Over the last few years there has been intense work to streamline the computing infrastructure in preparation for data, which started to flow in from the far detector in Fall 2013. Major accomplishments for this effort include migration to the use of off-site resources through the use of the Open Science Grid and upgrading the file-handling framework from simple disk storage to a tiered system using a comprehensive data management and delivery system to find and access files on either disk or tape storage. NOvA has already produced more than 6.5 million files and more than 1 PB of raw data and Monte Carlo simulation files which are managed under this model. The current system has demonstrated sustained rates of up to 1 TB/hour of file transfer by the data handling system. NOvA pioneered the use of new tools and this paved the way for their use by other Intensity Frontier experiments at Fermilab. Most importantly, the new framework places the experiment's infrastructure on a firm foundation, and is ready to produce the files needed for first physics.

Recent Evolution of the Offline Computing Model of the NOvA Experiment

International Nuclear Information System (INIS)

Habig, Alec; Group, Craig; Norman, A.

2015-01-01

The NOvA experiment at Fermilab is a long-baseline neutrino experiment designed to study νe appearance in a ν μ beam. Over the last few years there has been intense work to streamline the computing infrastructure in preparation for data, which started to flow in from the far detector in Fall 2013. Major accomplishments for this effort include migration to the use of off-site resources through the use of the Open Science Grid and upgrading the file-handling framework from simple disk storage to a tiered system using a comprehensive data management and delivery system to find and access files on either disk or tape storage. NOvA has already produced more than 6.5 million files and more than 1 PB of raw data and Monte Carlo simulation files which are managed under this model. The current system has demonstrated sustained rates of up to 1 TB/hour of file transfer by the data handling system. NOvA pioneered the use of new tools and this paved the way for their use by other Intensity Frontier experiments at Fermilab. Most importantly, the new framework places the experiment's infrastructure on a firm foundation, and is ready to produce the files needed for first physics. (paper)

Laser surveillance system for spent fuel

International Nuclear Information System (INIS)

Fiarman, S.; Zucker, M.S.; Bieber, A.M. Jr.

1980-01-01

A laser surveillance system installed at spent fuel storage pools (SFSP's) will provide the safeguard inspector with specific knowledge of spent fuel movement that cannot be obtained with current surveillance systems. The laser system will allow for the division of the pool's spent fuel inventory into two populations - those assemblies which have been moved and those which haven't - which is essential for maximizing the efficiency and effectiveness of the inspection effort. We have designed, constructed, and tested a full size laser system operating in air and have used an array of 6 zircaloy BWR tubes to simulate an assembly. The reflective signal from the zircaloy rods is a strong function of position of the assembly, but in all cases is easily discernable from the reference scan of the background with no assembly. A design for a SFSP laser surveillance system incorporating laser ranging is discussed. 10 figures

NEAR-IR STUDIES OF RECURRENT NOVA V745 SCORPII DURING ITS 2014 OUTBURST

International Nuclear Information System (INIS)

Banerjee, D. P. K.; Joshi, Vishal; Venkataraman, V.; Ashok, N. M.; Raj, A.; Marion, G. H.; Hsiao, E. Y.

2014-01-01

The recurrent nova V745 Scorpii underwent its third known outburst on 2014 February 6. Infrared monitoring of the eruption on an almost daily basis, starting from 1.3 days after discovery, shows the emergence of a powerful blast wave generated by the high velocity nova ejecta exceeding 4000 km s –1 plowing into its surrounding environment. The temperature of the shocked gas is raised to a high value exceeding 10 8 K immediately after outburst commencement. The energetics of the outburst clearly surpass those of similar symbiotic systems like RS Oph and V407 Cyg which have giant secondaries. The shock does not show a free-expansion stage but rather shows a decelerative Sedov-Taylor phase from the beginning. Such strong shock fronts are known to be sites for γ-ray generation. V745 Sco is the latest nova, apart from five other known novae, to show γ-ray emission. It may be an important testbed to resolve the crucial question of whether or not all novae are generically γ-ray emitters by virtue of having a circumbinary reservoir of material that is shocked by the ejecta rather than γ-ray generation being restricted to only symbiotic systems with a shocked red giant (RG) wind. The lack of a free-expansion stage favors V745 Sco to have a density enhancement around the white dwarf (WD), above that contributed by a RG wind. Our analysis also suggests that the WD in V745 Sco is very massive and a potential progenitor for a future SN Ia explosion

The Evolution of NR TrA (Nova TrA 2008) from 2008 through 2017

Science.gov (United States)

Walter, Frederick M.; Burwitz, Vadim; Kafka, Stella

2018-06-01

The classical nova NR TrA was discovered as an O-type optically-thick classical nova. There is no evidence that it formed dust. Within four years the envelope became sufficiently thin to reveal an eclipsing accretion disk-dominated system with orbitally-modulated permitted lines of C IV, N V, and O VI. XMM observations reveal a non-eclipsing soft X-ray source and a deeply-eclipsing UV continuum. We will present the first ten years of optical spectral evolution of this system accompanied by ten years of BVRIJHK photometry, with an eye to deciphering the current nature of the system.

Fluorescence-pumped photolytic gas laser system for a commercial laser fusion power plant

International Nuclear Information System (INIS)

Monsler, M.J.

1977-01-01

The first results are given for the conceptual design of a short-wavelength gas laser system suitable for use as a driver (high average power ignition source) for a commercial laser fusion power plant. A comparison of projected overall system efficiencies of photolytically excited oxygen, sulfur, selenium and iodine lasers is described, using a unique windowless laser cavity geometry which will allow scaling of single amplifier modules to 125 kJ per aperture for 1 ns pulses. On the basis of highest projected overall efficiency, a selenium laser is chosen for a conceptual power plant fusion laser system. This laser operates on the 489 nm transauroral transition of selenium, excited by photolytic dissociation of COSe by ultraviolet fluorescence radiation. Power balances and relative costs for optics, electrical power conditioning and flow conditioning of both the laser and fluorescer gas streams are discussed for a system with the following characteristics: 8 operating modules, 2 standby modules, 125 kJ per module, 1.4 pulses per second, 1.4 MW total average power. The technical issues of scaling visible and near-infrared photolytic gas laser systems to this size are discussed

Big and Little Feet Provincial Profiles: Nova Scotia

Directory of Open Access Journals (Sweden)

Sarah Dobson

2017-09-01

Full Text Available This communiqué provides a summary of the production- and consumption-based greenhouse gas emissions accounts for Nova Scotia, as well as their associated trade flows. It is part of a series of communiqués profiling the Canadian provinces and territories.1 In simplest terms, a production-based emissions account measures the quantity of greenhouse gas emissions produced in Nova Scotia. In contrast, a consumption-based emissions account measures the quantity of greenhouse gas emissions generated during the production process for final goods and services that are consumed in Nova Scotia through household purchases, investment by firms and government spending. Trade flows refer to the movement of emissions that are produced in Nova Scotia but which support consumption in a different province, territory or country (and vice versa. For example, emissions at the Port of Halifax that are associated with goods that are subsequently exported to Ontario for sale are recorded as a trade flow from Nova Scotia to Ontario. Moving in the opposite direction, emissions associated with the production of motor gasoline in New Brunswick that is exported to Nova Scotia for sale are recorded as a trade flow from New Brunswick to Nova Scotia. For further details on these results in a national context, the methodology for generating them and their policy implications, please see the companion papers to this communiqué series: (1 Fellows and Dobson (2017; and (2 Dobson and Fellows (2017. Additionally, the consumption emissions and trade flow data for each of the provinces and territories are available at: http://www.policyschool.ca/embodied-emissions-inputs-outputs-datatables-2004-2011/.

Infant-mortality testing of high-energy-density capacitors used on Nova

International Nuclear Information System (INIS)

Merritt, B.T.; Whitham, K.

1983-01-01

Nova is a solid-state large laser for inertial-confinement fusion research. Its flashlamps are driven by a 60-MJ capacitor bank. Part of this bank is being built with high-energy-density capacitors, 52-μF, 22 kV, 12.5 kJ. A total of 2645 of these capacitors have been purchased from two manufacturers. Each capacitor was infant-mortality tested. The first test consisted of a high-potential test, bushing-to-case, since these capacitors have dual bushings. Then the capacitors were discharged 500 times with circuit conditions approximating the capacitors normal flashlamp load. Failure of either of these tests or if the capacitor was leaking was cause for rejection

Laser experimental system as teaching aid for demonstrating basic phenomena of laser feedback

International Nuclear Information System (INIS)

Xu, Ling; Zhao, Shijie; Zhang, Shulian

2015-01-01

An experimental laser teaching system is developed to demonstrate laser feedback phenomena, which bring great harm to optical communication and benefits to precision measurement. The system consists of an orthogonally polarized He-Ne laser, a feedback mirror which reflects the laser output light into the laser cavity, and an optical attenuator which changes the intensity of the feedback light. As the feedback mirror is driven by a piezoelectric ceramic, the attenuator is adjusted and the feedback mirror is tilted, the system can demonstrate many basic laser feedback phenomena, including weak, moderate and strong optical feedback, multiple feedback and polarization flipping. Demonstrations of these phenomena can give students a better understanding about the intensity and polarization of lasers. The system is well designed and assembled, simple to operate, and provides a valuable teaching aid at an undergraduate level. (paper)

Continuum emission from classical nova winds

International Nuclear Information System (INIS)

Harkness, R.P.

1983-01-01

The emergent continuum of a slow classical nova during outburst is considered in the quasi-steady optically thick, transonic wind model. Models are presented for various steady mass loss rates and are related to the evolution of slow novae during decline and early post-maximum. The continuum emission is found to depart radically from a blackbody spectrum and to exhibit features common to highly extended stellar atmospheres. (author)

The Shape of Long Outbursts in U Gem Type Dwarf Novae from AAVSO Data

Science.gov (United States)

Cannizzo, John K.

2012-01-01

We search the American Association of Variable Star Observers (AAVSO) archives of the two best studied dwarf novae in an attempt to find light curves for long out bursts that are extremely well-characterized. The systems are U Gem and S8 Cyg. Our goal is to search for embedded precursors such as those that have been found recently in the high fidelity Kepler data for superoutbursts of some members of the 8U UMa subclass of dwarf novae. For the vast majority of AAV80 data, the combination of low data cadence and large errors associated with individual measurements precludes one from making any strong statement about the shape of the long outbursts. However, for a small number of outbursts, extensive long term monitoring with digital photometry yields high fidelity light curves. We report the finding of embedded precursors in two of three candidate long outbursts. This reinforces van Paradijs' finding that long outbursts in dwarf novae above the period gap and superoutbursts in systems below the period gap constitute a unified class. The thermal-tidal instability to account for superoutbursts in the SU UMa stars predicts embedded precursors only for short orbital period dwarf novae, therefore the presence of embedded precursors in long orbital period systems - U Gem and SS Cyg - argues for a more general mechanism to explain long outbursts.

Dynamically variable spot size laser system

Science.gov (United States)

Gradl, Paul R. (Inventor); Hurst, John F. (Inventor); Middleton, James R. (Inventor)

2012-01-01

A Dynamically Variable Spot Size (DVSS) laser system for bonding metal components includes an elongated housing containing a light entry aperture coupled to a laser beam transmission cable and a light exit aperture. A plurality of lenses contained within the housing focus a laser beam from the light entry aperture through the light exit aperture. The lenses may be dynamically adjusted to vary the spot size of the laser. A plurality of interoperable safety devices, including a manually depressible interlock switch, an internal proximity sensor, a remotely operated potentiometer, a remotely activated toggle and a power supply interlock, prevent activation of the laser and DVSS laser system if each safety device does not provide a closed circuit. The remotely operated potentiometer also provides continuous variability in laser energy output.

Laser and plasma diagnostics for the OMEGA Upgrade Laser System (invited) (abstract)

International Nuclear Information System (INIS)

Letzring, S.A.

1995-01-01

The upgraded OMEGA laser system will be capable of delivering up to 30 kJ of 351-nm laser light with various temporal pulse shapes onto a variety of targets for both ICF and basic plasma physics experiments. ICF experiments will cover a wide parameter space up to near-ignition conditions, and basic interaction and plasma physics experiments will cover previously unattainable parameter spaces. The laser system is the tool with which the experiments are performed; the diagnostics, both of the laser system and the interaction between the laser and the target, form the heart of the experiment. A new suite of diagnostics is now being designed and constructed. Most of these are based on diagnostics previously fielded on the OMEGA laser system very successfully over the last ten years, but there are some new diagnostics, both for the laser and the interaction experiments, which have had to be invented. Laser system diagnostics include high-energy, full-beam calorimetry for all of the 60 beams of the upgrade; a novel, multispectral energy-measuring system for assessing the tuning of the frequency-multiplying crystals; a beam-balance diagnostic that forms the heart of the energy-balance system; and a peak power diagnostic that forms the heart of the power-balance system. Target diagnostics will include the usual time-integrated x-ray imaging systems, both pinhole cameras and x-ray microscopes; x-ray spectrometers, both imaging and spatially integrating; plamsa calorimeters, including x-ray calorimetry; and time-resolved x-ray diagnostics, both nonimaging and imaging in one and two dimensions. Neutron diagnostics will include several measurements of total yield, secondary, and possibly tertiary yield and neutron spectroscopy with several time-of-flight spectrometers. Other measurements will include ''knock-on'' particle measurements and neutron activation of shell materials as a diagnostic of compressed fuel and shell density

Educational Technology Program for Nova Scotia: Initial Phase. A Report on the Federal-Provincial Study of Educational Technology in Nova Scotia.

Science.gov (United States)

deVille, Barry, Ed.

This is a preliminary examination of the present status and future prospects of educational technology in Nova Scotian schools. It is aimed at developing a plan to enhance the quality of educational technology by concentrating on systems which will be conducive to realizing educational goals at a reasonable cost. An overview of the institutional…

Shiva laser system performance

International Nuclear Information System (INIS)

Glaze, J.; Godwin, R.O.; Holzrichter, J.F.

1978-01-01

On November 18, 1977, after four years of experimentation, innovation, and construction, the Shiva High Energy Laser facility produced 10.2 kJ of focusable laser energy delivered in a 0.95 ns pulse. The Shiva laser, with its computer control system and delta amplifiers, demonstrated its versatility on May 18, 1978, when the first 20-beam target shot with delta amplifiers focused 26 TW on a target and produced a yield of 7.5 x 10 9 neutrons

Novae, supernovae, and the island universe hypothesis

International Nuclear Information System (INIS)

Van Den Bergh, S.

1988-01-01

Arguments in Curtis's (1917) paper related to the island universe hypothesis and the existence of novae in spiral nebulae are considered. It is noted that the maximum magnitude versus rate-of-decline relation for novae may be the best tool presently available for the calibration of the extragalactic distance scale. Light curve observations of six novae are used to determine a distance of 18.6 + or - 3.5 MPc to the Virgo cluster. Results suggest that Type Ia supernovae cannot easily be used as standard candles, and that Type II supernovae are unsuitable as distance indicators. Factors other than precursor mass are probably responsible for determining the ultimate fate of evolving stars. 83 references

NOVA: a software to analyze complexome profiling data

NARCIS (Netherlands)

Giese, H.; Ackermann, J.; Heide, H.; Bleier, L.; Drose, S.; Wittig, I.; Brandt, U.; Koch, I.

2015-01-01

SUMMARY: We introduce nova, a software for the analysis of complexome profiling data. nova supports the investigation of the composition of complexes, cluster analysis of the experimental data, visual inspection and comparison of experiments and many other features. AVAILABILITY AND IMPLEMENTATION:

NOVAE WITH LONG-LASTING SUPERSOFT EMISSION THAT DRIVE A HIGH ACCRETION RATE

International Nuclear Information System (INIS)

Schaefer, Bradley E.; Collazzi, Andrew C.

2010-01-01

We identify a new class of novae characterized by the post-eruption quiescent light curve being more than roughly a factor of 10 brighter than the pre-eruption light curve. Eight novae (V723 Cas, V1500 Cyg, V1974 Cyg, GQ Mus, CP Pup, T Pyx, V4633 Sgr, and RW UMi) are separated out as being significantly distinct from other novae. This group shares a suite of uncommon properties, characterized by the post-eruption magnitude being much brighter than before eruption, short orbital periods, long-lasting supersoft emission following the eruption, a highly magnetized white dwarf (WD), and secular declines during the post-eruption quiescence. We present a basic physical picture which shows why all five uncommon properties are causally connected. In general, novae show supersoft emission due to hydrogen burning on the WD in the final portion of the eruption, and this hydrogen burning will be long-lasting if new hydrogen is poured onto the surface at a sufficient rate. Most novae do not have adequate accretion for continuous hydrogen burning, but some can achieve this if the companion star is nearby (with short orbital period) and a magnetic field channels the matter onto a small area on the WD so as to produce a locally high accretion rate. The resultant supersoft flux irradiates the companion star and drives a higher accretion rate (with a brighter post-eruption phase), which serves to keep the hydrogen burning and the supersoft flux going. The feedback loop cannot be perfectly self-sustaining, so the supersoft flux will decline over time, forcing a decline in the accretion rate and the system brightness. We name this new group after the prototype, V1500 Cyg. V1500 Cyg stars are definitely not progenitors of Type Ia supernovae. The V1500 Cyg stars have similar physical mechanisms and appearances as predicted for nova by the hibernation model, but with this group accounting for only 14% of novae.

Design of a {O}94 cm mirror mount for the Petawatt Project on Nova

Energy Technology Data Exchange (ETDEWEB)

Hamilton, R.; Tietbohl, G.L.

1995-10-01

The authors have designed a large optical gimbal mount that will be used on the Petawatt Project currently under construction on the Nova laser. These mounts are designed to hold and tilt {O}94 cm mirrors and gratings that will redirect the {O}60 cm beam through the Petawatt vacuum compressor. Lacking the commercial availability to house this size optic, they have engineered a large mirror mount with a high natural frequency (42 Hz), low self-weight deflection of the mirror (< {lambda}/46), and high positioning accuracy characteristics (< 1 {micro}rad using flexures and stepping motors). Analysis details and methodology are presented.

Design of a OE 94 cm mirror mount for the Petawatt Project on Nova

International Nuclear Information System (INIS)

Hamilton, R.; Tietbohl, G.L.

1995-10-01

The authors have designed a large optical gimbal mount that will be used on the Petawatt Project currently under construction on the Nova laser. These mounts are designed to hold and tilt OE 94 cm mirrors and gratings that will redirect the OE 60 cm beam through the Petawatt vacuum compressor. Lacking the commercial availability to house this size optic, they have engineered a large mirror mount with a high natural frequency (42 Hz), low self-weight deflection of the mirror (< λ/46), and high positioning accuracy characteristics (< 1 microrad using flexures and stepping motors). Analysis details and methodology are presented

A new method of determining the ejected mass of novae

Energy Technology Data Exchange (ETDEWEB)

Sparks, W.M.

1994-12-31

A new method of determining the ejected mass of novae based on simple, reasonable assumptions is presented. This method assumes that the remnant mass on the white dwarf is the same as that from the previous nova outburst. The hydrogen, helium, and metal abundances of the accreted material from the secondary must also be known or assumed. The white dwarf`s mass has a small effect because the amount of hydrogen consumed during the thermonuclear runaway only depends weakly upon this mass. If the composition of the ejecta and the time of the remnant shell burnout are determined from observations, then the ejected and remnant masses can be deduced. At present only a sharp decrease in the X-rays observed by ROSAT has been attributed to this remnant burnout and only for two novae: GQ Mus and V1974 Cyg. The ejected and remnant masses for these two novae are calculated. If other indicators of nova remnant burnout, such as a rapid decrease in high-ionization lines, can be identified, then this method could be applied to additional novae.

New sidescan sonar and gravity evidence that the Nova-Canton Trough is a fracture zone

Science.gov (United States)

Joseph, Devorah; Taylor, Brian; Shor, Alexander N.

1992-05-01

A 1990 sidescan sonar survey in the eastern region of the Nova-Canton Trough mapped 138°-striking abyssal-hill fabric trending into 70°-striking trough structures. The location and angle of intersection of the abyssal hills with the eastern Nova-Canton Trough effectively disprove a spreading-center origin of this feature. Free-air gravity anomalies derived from satellite altimetry data show continuity, across the Line Islands, of the Nova-Canton Trough with the Clipperton Fracture Zone. The Canton-Clipperton trend is copolar, about a pole at 30°S, 152°W, with other coeval Pacific-Farallon fracture-zone segments, from the Pau to Marquesas fracture zones. This copolarity leads us to postulate a Pacific-Farallon spreading pattern for the magnetic quiet zone region north and east of the Manihiki Plateau, with the Nova-Canton Trough originating as a transform fault in this system.

THE {sup 7}Be ii RESONANCE LINES IN TWO CLASSICAL NOVAE V5668 SGR AND V2944 OPH

Energy Technology Data Exchange (ETDEWEB)

Tajitsu, Akito [Subaru Telescope, National Astronomical Observatory of Japan, 650 North A’ohoku Place, Hilo, HI 96720 (United States); Sadakane, Kozo [Astronomical Institute, Osaka Kyoiku University, Asahigaoka, Kashiwara, Osaka 582-8582 (Japan); Naito, Hiroyuki [Nayoro Observatory, 157-1 Nisshin, Nayoro, Hokkaido 096-0066 (Japan); Arai, Akira; Kawakita, Hideyo [Koyama Astronomical Observatory, Kyoto Sangyo University, Motoyama, Kamigamo, Kita-ku, Kyoto 603-8555 (Japan); Aoki, Wako, E-mail: tajitsu@naoj.org [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)

2016-02-20

We report spectroscopic observations of the resonance lines of singly ionized {sup 7}Be in the blueshifted absorption line systems found in the post-outburst spectra of two classical novae—V5668 Sgr (Nova Sagittarii 2015 No. 2) and V2944 Oph (Nova Ophiuchi 2015). The unstable isotope {sup 7}Be should have been created during the thermonuclear runaway (TNR) of these novae and decayed to form {sup 7}Li within a short period (a half-life of 53.22 days). These confirmations of {sup 7}Be are the second and the third ones following the first case found in V339 Del by Tajitsu et al. The blueshifted absorption line systems in both novae are clearly divided into two velocity components, both of which contain {sup 7}Be. This means that the absorbing gases in both velocity components consist of products of TNR. We estimated the amounts of {sup 7}Be produced during the outbursts of both novae and concluded that significant {sup 7}Li should have been created. These findings strongly suggest that the explosive production of {sup 7}Li via the reaction {sup 3}He(α,γ){sup 7}Be and its  subsequent decay to {sup 7}Li occurs frequently among classical novae and contributes to the process of Galactic Li enrichment.

A wave model for dwarf novae

International Nuclear Information System (INIS)

Sparks, W.M.; Kutter, G.S.

1980-01-01

The rapid coherent oscillation during a dwarf nova outburst is attributed to an accretion-driven wave going around the white dwarf component of the binary system. The increase and decrease in the period of this oscillation is due to the change in the velocity of the wave as it is first being driven and then damped. Qualitatively, a large number of observations can be explained with such a model. The beginnings of a mathematical representation of this model are developed. (orig.)

Review of the classical nova outburst

International Nuclear Information System (INIS)

Starrfield, S.; Sparks, W.M.

1986-06-01

Observational studies have not only identified a new class of novae but theoretical simulations of this class have been found to be in excellent agreement with the observations. This new class consists of outbursts occurring on ONeMg white dwarfs in close binar systems in contrast to the other outbursts which are occurring on CO white dwarfs. We also review the effects of the β + -unstable nuclei and show how their presence has a major effect on the evolution. 77 refs

Efficacy and patient satisfaction after NovaSure and Minerva endometrial ablation for treating abnormal uterine bleeding: a retrospective comparative study.

Science.gov (United States)

Scordalakes, Constantine; delRosario, Robert; Shimer, Andrew; Stankiewicz, Russell

2018-01-01

Compare amenorrhea rate, menstrual symptoms, patient satisfaction, and adverse events in women who underwent endometrial ablation with the NovaSure versus the Minerva radiofrequency ablation systems. We surveyed 189 premenopausal women (mean 40.8±6.2 years old) who underwent endometrial ablation for abnormal uterine bleeding using the NovaSure (n=97) or Minerva (n=92) systems, at four private US gynecology clinics, and whose procedure date was after July 2015 with follow-up ≥3 months. Women were surveyed an average of 11.3±3.9 months (range 137-532 days) after ablation. The subject-reported amenorrhea rate was 52% higher in NovaSure subjects than Minerva subjects (64% and 42%, respectively; p =0.004). Age and bleeding cyclicity did not affect amenorrhea rate in either group. Normal-to-no bleeding was reported by >90% of subjects after either treatment. NovaSure was significantly more effective than Minerva at reducing pad/tampon use in women with any residual bleeding (2.4±5.2 items/day versus 4.7±5.5 items/day, p =0.049). NovaSure was significantly more effective than Minerva at reducing premenstrual syndrome (PMS) symptoms ( p =0.019) and menstrual pain ( p =0.003), and more NovaSure subjects (94%) than Minerva subjects (78%) were satisfied with clinical outcomes ( p =0.003). Adverse events did not differ by treatment; three women in each group progressed to hysterectomy. While overall bleeding reduction in premenopausal women with abnormal uterine bleeding was excellent with either endometrial ablation system, NovaSure treatment resulted in a higher patient-reported 1-year amenorrhea rate, and women with residual bleeding used fewer pads and tampons than Minerva-treated women. Additionally, NovaSure subjects reported better menstrual-related life quality and PMS symptom alleviation, and greater satisfaction with outcomes than Minerva-treated women.

High-performance OPCPA laser system

International Nuclear Information System (INIS)

Zuegel, J.D.; Bagnoud, V.; Bromage, J.; Begishev, I.A.; Puth, J.

2006-01-01

Optical parametric chirped-pulse amplification (OPCPA) is ideally suited for amplifying ultra-fast laser pulses since it provides broadband gain across a wide range of wavelengths without many of the disadvantages of regenerative amplification. A high-performance OPCPA system has been demonstrated as a prototype for the front end of the OMEGA Extended Performance (EP) Laser System. (authors)

High-performance OPCPA laser system

Energy Technology Data Exchange (ETDEWEB)

Zuegel, J.D.; Bagnoud, V.; Bromage, J.; Begishev, I.A.; Puth, J. [Rochester Univ., Lab. for Laser Energetics, NY (United States)

2006-06-15

Optical parametric chirped-pulse amplification (OPCPA) is ideally suited for amplifying ultra-fast laser pulses since it provides broadband gain across a wide range of wavelengths without many of the disadvantages of regenerative amplification. A high-performance OPCPA system has been demonstrated as a prototype for the front end of the OMEGA Extended Performance (EP) Laser System. (authors)

ARGOS laser system mechanical design

Science.gov (United States)

Deysenroth, M.; Honsberg, M.; Gemperlein, H.; Ziegleder, J.; Raab, W.; Rabien, S.; Barl, L.; Gässler, W.; Borelli, J. L.

2014-07-01

ARGOS, a multi-star adaptive optics system is designed for the wide-field imager and multi-object spectrograph LUCI on the LBT (Large Binocular Telescope). Based on Rayleigh scattering the laser constellation images 3 artificial stars (at 532 nm) per each of the 2 eyes of the LBT, focused at a height of 12 km (Ground Layer Adaptive Optics). The stars are nominally positioned on a circle 2' in radius, but each star can be moved by up to 0.5' in any direction. For all of these needs are following main subsystems necessary: 1. A laser system with its 3 Lasers (Nd:YAG ~18W each) for delivering strong collimated light as for LGS indispensable. 2. The Launch system to project 3 beams per main mirror as a 40 cm telescope to the sky. 3. The Wave Front Sensor with a dichroic mirror. 4. The dichroic mirror unit to grab and interpret the data. 5. A Calibration Unit to adjust the system independently also during day time. 6. Racks + platforms for the WFS units. 7. Platforms and ladders for a secure access. This paper should mainly demonstrate how the ARGOS Laser System is configured and designed to support all other systems.

Optical system for UV-laser technological equipment

Science.gov (United States)

Fedosov, Yuri V.; Romanova, Galina E.; Afanasev, Maxim Ya.

2017-09-01

Recently there has been an intensive development of intelligent industrial equipment that is highly automated and can be rapidly adjusted for certain details. This equipment can be robotics systems, automatic wrappers and markers, CNC machines and 3D printers. The work equipment considered is the system for selective curing of photopolymers using a UV-laser and UV-radiation in such equipment that leads to additional technical difficulties. In many cases for transporting the radiation from the laser to the point processed, a multi-mirror system is used: however, such systems are usually difficult to adjust. Additionally, such multi-mirror systems are usually used as a part of the equipment for laser cutting of metals using high-power IR-lasers. For the UV-lasers, using many mirrors leads to crucial radiation losses because of many reflections. Therefore, during the development of the optical system for technological equipment using UV-laser we need to solve two main problems: to transfer the radiation for the working point with minimum losses and to include the system for controlling/handling the radiation spot position. We introduce a system for working with UV-lasers with 450mW of power and a wavelength of 0.45 μm based on a fiber system. In our modelling and design, we achieve spot sizes of about 300 μm, and the designed optical and mechanical systems (prototypes) were manufactured and assembled. In this paper, we present the layout of the technological unit, the results of the theoretical modelling of some parts of the system and some experimental results.

Cost analysis of lasers for a laser isotope separation system. Final report

International Nuclear Information System (INIS)

Mail, R.A.; Markovich, F.J.; Carr, R.H.

1977-01-01

To be of practical significance, laser isotope separation (LIS) for separation of 235 U from 238 U must exhibit attributes which make it preferable to expansion of the present facilities. Clearly the most attractive such attribute is the prospect of significant cost reductions, which preliminary studies at LLL suggest will amount to a factor of three and perhaps as much as ten. From these preliminary studies, it appears that the lasers themselves account for a very substantial portion of the capital cost of a LIS system, and a significant portion of the equipment replacement costs. Since the laser costs are so pivotal to the system cost, and the system cost is so pivotal to the choice of separation techniques, it is clear that a more detailed investigation of laser costs is required. Results are presented of a study performed by General Research Corporation (GRC) to assess the cost of lasers in a production laser isotope separation (LIS) plant

Short pulse laser systems for biomedical applications

CERN Document Server

Mitra, Kunal

2017-01-01

This book presents practical information on the clinical applications of short pulse laser systems and the techniques for optimizing these applications in a manner that will be relevant to a broad audience, including engineering and medical students as well as researchers, clinicians, and technicians. Short pulse laser systems are useful for both subsurface tissue imaging and laser induced thermal therapy (LITT), which hold great promise in cancer diagnostics and treatment. Such laser systems may be used alone or in combination with optically active nanoparticles specifically administered to the tissues of interest for enhanced contrast in imaging and precise heating during LITT. Mathematical and computational models of short pulse laser-tissue interactions that consider the transient radiative transport equation coupled with a bio-heat equation considering the initial transients of laser heating were developed to analyze the laser-tissue interaction during imaging and therapy. Experiments were first performe...

Radio Observations of Gamma-ray Novae

Science.gov (United States)

Linford, Justin D.; Chomiuk, L.; Ribeiro, V.; project, E.-Nova

2014-01-01

Recent detection of gamma-ray emission from classical novae by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope surprised many in the astronomical community. We present results from radio observations, obtained using the Karl G. Jansky Very Large Array (VLA), of three gamma-ray novae: Mon2012, Sco2012, and Del2013. Radio observations allow for the calculation of ejecta masses, place limits on the distances, and provide information about the gamma-ray emission mechanism for these sources.

ToO Galactic Nova -- Michelle ``Quick Response''

Science.gov (United States)

Helton, L. Andrew; Woodward, Chick; Evans, Nye; Geballe, Tom; Spitzer Nova Team

2006-08-01

Stars are the engines of energy production and chemical evolution in our Universe, depositing radiative and mechanical energy into their environments and enriching the ambient ISM with elements synthesized in their interiors and dust grains condensed in their atmospheres. Classical novae (CN) contribute to this cycle of chemical enrichment through explosive nucleosynthesis and the violent ejection of material dredged from the white dwarf progenitor and mixed with the accreted surface layers. We propose to obtain mid-IR spectra of a new galactic CN in outburst to investigate aspects of the CN phenomenon including the in situ formation and mineralogy of nova dust and the elemental abundances resulting from thermonuclear runaway. Synoptic, high S/N Michelle spectra permit: 1) determination of the grain size distribution and mineral composition of nova dust; 2) estimation of chemical abundances of nova ejecta from coronal and other emission line spectroscopy; and 3) measurement of the density and masses of the ejecta. This Gemini `Target of Opportunity' initiative (trigger K=5- 8 mag, assuming adequate PWFS guide stars exist) complements our extensive Spitzer, Chandra, Swift, XMM-Newton CN DDT/ToO programs.

Synoptic Mid-IR Spectra ToO Novae

Science.gov (United States)

Helton, L. Andrew; Woodward, Chick; Evans, Nye; Geballe, Tom; Spitzer Nova Team

2007-02-01

Stars are the engines of energy production and chemical evolution in our Universe, depositing radiative and mechanical energy into their environments and enriching the ambient ISM with elements synthesized in their interiors and dust grains condensed in their atmospheres. Classical novae (CN) contribute to this cycle of chemical enrichment through explosive nucleosynthesis and the violent ejection of material dredged from the white dwarf progenitor and mixed with the accreted surface layers. We propose to obtain mid-IR spectra of a new galactic CN in outburst to investigate aspects of the CN phenomenon including the in situ formation and mineralogy of nova dust and the elemental abundances resulting from thermonuclear runaway. Synoptic, high S/N Michelle spectra permit: 1) determination of the grain size distribution and mineral composition of nova dust; 2) estimation of chemical abundances of nova ejecta from coronal and other emission line spectroscopy; and 3) measurement of the density and masses of the ejecta. This Gemini `Target of Opportunity' initiative (trigger K=5- 8 mag, assuming adequate PWFS guide stars exist) complements our extensive Spitzer, Chandra, Swift, XMM-Newton CN DDT/ToO programs.

The SSS classical nova V5116 Sgr

Science.gov (United States)

Sala, G.; Ness, J.; Greiner, J.; Hernanz, M.

2017-10-01

XMM-Newton observed the nova V5116 Sgr during its supersoft phase (SSS). V5116 Sgr showed a decrease of the flux by a factor around 8 during 2/3 of the orbital period. The broad band EPIC spectra remain unchanged during the different flux phases, suggesting an occultation of the central source in a high inclination system. While the global SED does not change significantly, the RGS spectrum is changing between the high and the low flux phases. The non-occultation phase shows a typical white dwarf atmosphere spectrum, dominated by absorption lines. During the low flux periods an extra component of emission lines is superimposed to the soft X-ray continuum. This supports the picture of V5116 Sgr as the clearest example of a system switching between the SSa class of SSS novae, with spectra dominated by absorption lines, and the SSe class, showing an emission lines component. In addition, the simultaneous OM images allow us to find a phase solution for the X-ray light-curve. A thick rim of the accretion disk as the one developed for the SSSs CAL 87, RX J0019.8, and RX J0513.9 could provide a plausible model both for the optical and the X-ray light curve of V5116 Sgr.

Laser Safety and Hazard Analysis for the Trailer (B70) Based AURA Laser System

International Nuclear Information System (INIS)

AUGUSTONI, ARNOLD L.

2003-01-01

A laser safety and hazard analysis was performed for the AURA laser system based on the 2000 version of the American National Standards Institute's (ANSI) Standard Z136.1, for ''Safe Use of Lasers'' and the 2000 version of the ANSI Standard Z136.6, for ''Safe Use of Lasers Outdoors''. The trailer based AURA laser system is a mobile platform, which is used to perform laser interaction experiments and tests at various national test sites. The trailer (B70) based AURA laser system is generally operated on the United State Air Force Starfire Optical Range (SOR) at Kirtland Air Force Base (KAFB), New Mexico. The laser is used to perform laser interaction testing inside the laser trailer as well as outside the trailer at target sites located at various distances from the exit telescope. In order to protect personnel, who work inside the Nominal Hazard Zone (NHZ), from hazardous laser emission exposures it was necessary to determine the Maximum Permissible Exposure (MPE) for each laser wavelength (wavelength bands) and calculate the appropriate minimum Optical Density (OD min ) of the laser safety eyewear used by authorized personnel and the Nominal Ocular Hazard Distance (NOHD) to protect unauthorized personnel who may have violated the boundaries of the control area and enter into the laser's NHZ

Laser Pyro System Standardization and Man Rating

Science.gov (United States)

Brown, Christopher W.

2004-01-01

This viewgraph presentation reviews an X-38 laser pyro system standardization system designed for a new manned rated program. The plans to approve this laser initiation system and preliminary ideas for this system are also provided.

Energy distributions of symbiotic novae

International Nuclear Information System (INIS)

Bryan, G.L.; Kwok, S.

1991-01-01

The IRAS low-resolution spectra of three recent symbiotic novae are fitted with a dust continuum radiative transfer model. It is found that the dust shells are detached from the photosphere and that the sizes of the inner radii are correlated with times since outburst. An analysis of the IUE spectra of HM Sge at different epochs suggests that the strength of the 2200 A feature is decreasing with times and the grains responsible for the feature are probably formed in the white dwarf ejecta. A complete accounting of the entire energy budget from radio to X-ray shows that most of the energy is emitted by the cool component in the infrared, and a significant fraction of the flux of the hot component is escaping in the far-ultraviolet. The density-bounded nature of the circumstellar gas nebulae could be the result of a bipolar geometry of the nebulae. Unlike classical novae, the optical outburst of symbiotic novae is due to the ionization of the preexisting envelope of the cool component and is not the result of a sudden ejection by the hot component. 55 refs

Laser driven hydrodynamic instability experiments

International Nuclear Information System (INIS)

Remington, B.A.; Weber, S.V.; Haan, S.W.; Kilkenny, J.D.; Glendinning, S.G.; Wallace, R.J.; Goldstein, W.H.; Wilson, B.G.; Nash, J.K.

1993-01-01

An extensive series of experiments has been conducted on the Nova laser to measure hydrodynamic instabilities in planar foils accelerated by x-ray ablation. Single mode experiments allow a measurement of the fundamental growth rates from the linear well into the nonlinear regime. Two-mode foils allow a first direct observation of mode coupling. Surface-finish experiments allow a measurement of the evolution of a broad spectrum of random initial modes

The geographic accessibility of pharmacies in Nova Scotia.

Science.gov (United States)

Law, Michael R; Heard, Deborah; Fisher, Judith; Douillard, Jay; Muzika, Greg; Sketris, Ingrid S

2013-01-01

Geographic proximity is an important component of access to primary care and the pharmaceutical services of community pharmacies. Variations in access to primary care have been found between rural and urban areas in Canadian and international jurisdictions. We studied access to community pharmacies in the province of Nova Scotia. We used information on the locations of 297 community pharmacies operating in Nova Scotia in June 2011. Population estimates at the census block level and network analysis were used to study the number of Nova Scotia residents living within 800 m (walking) and 2 km and 5 km (driving) distances of a pharmacy. We then simulated the impact of pharmacy closures on geographic access in urban and rural areas. We found that 40.3% of Nova Scotia residents lived within walking distance of a pharmacy; 62.6% and 78.8% lived within 2 km and 5 km, respectively. Differences between urban and rural areas were pronounced: 99.2% of urban residents lived within 5 km of a pharmacy compared with 53.3% of rural residents. Simulated pharmacy closures had a greater impact on geographic access to community pharmacies in rural areas than urban areas. The majority of Nova Scotia residents lived within walking or short driving distance of at least 1 community pharmacy. While overall geographic access appears to be lower than in the province of Ontario, the difference appears to be largely driven by the higher proportion of rural dwellers in Nova Scotia. Further studies should examine how geographic proximity to pharmacies influences patients' access to traditional and specialized pharmacy services, as well as health outcomes and adherence to therapy. Can Pharm J 2013;146:39-46.

Nova Scotia Energy Strategy : progress report

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-02-01

Nova Scotia's energy strategy addresses all aspects of energy production and use, from offshore oil and gas to electricity and coal, to climate change and renewable resources. It also encompasses energy conservation and efficiency. This progress report highlights the efforts that the province has made to promote exploration, improve efficiency of regulations and approval processes and promote the oil and natural gas sector. Efforts have also been made to support local businesses, address climate change issues and protect the environment. The strategy demonstrates how new energy resources can be used to build a more prosperous and self-reliant province. The progress report focuses on the following 3 themes: powering the economy; improving the environment; and, securing Nova Scotia's future. The report emphasizes that the growing oil and gas industry brings many opportunities for new jobs and a stronger economy. In the next 12 to 18 months, about 8 to 10 offshore exploration wells will be drilled, which is more than in the last decade. Funding will be provided to extend pipeline systems beyond franchise areas approved by the Nova Scotia Utility and Review Board. In May 2002, the Electricity Marketplace Governance Committee was formed to make recommendations on how competition can be introduced into the province's electricity market. The Department of Energy has been working to implement initiatives to increase the use of renewable energy sources such as solar and wind power. In October 2002, new wind turbines began producing electricity in 3 communities on Cape Breton Island. A key priority is to respond to climate change and reduce greenhouse gas emissions as well as emissions of mercury, sulphur, nitrogen, and ozone. The energy strategy also identifies the need to provide competitive taxation regimes.

The Nova-Canton Trough and the Late Cretaceous evolution of the central Pacific

Science.gov (United States)

Joseph, Devorah; Taylor, Brain; Shor, Alexander N.; Yamazaki, Toshitsugu

Free-air gravity anomalies derived from satellite altimetry data show that the major Pacific fracture zones, from the Pau to Marquesas, are co-polar about an Euler pole located at 150.5°W, 34.6°S for the period preceding chron 33 and including a large portion of the Cretaceous Normal Superchron. They also show continuity of the Clipperton Fracture Zone through the Line Islands to the Nova-Canton ridge and trough; this Canton-Clipperton trend is co-polar to the same pole. Sidescan-sonar and bathymetry data in the Nova-Canton Trough region reveal N140°E-striking abyssal hill topography south of the N70°E-striking structures of the Nova-Canton Trough and crustal fabric striking normal to the trough (N160°E) to the north. We conclude that the Nova-Canton Trough is the Middle Cretaceous extension of the Clipperton Fracture Zone. We propose that the anomalous depths (7000-8400 m) of the trough between 167°30'-168°30'W are the result of a complex plate reorganization. Conjugate magnetic anomaly lineations M1-M3 in the Phoenix lineations between the Central Pacific Fracture Zone and the Phoenix Fracture Zone and the absence of lineations younger than anomaly M3 west of the Phoenix Fracture Zone suggest that spreading may have gradually ceased along the Pacific-Phoenix system from west to east. We infer that the remaining active segment of the Pacific-Phoenix spreading system after anomaly M1 time was the easternmost section of the Phoenix lineations. At ˜M0 time, the Pacific-Phoenix spreading axis stretched from lineated bathymetric depressions lying between 180°W and the Phoenix Islands to ˜168°W and included the western deep of the Nova-Canton Trough. We hypothesize that accretion terminated on the Pacific-Phoenix spreading axis shortly after M0 time and that the absence of an M0 isochron in the region between the eastern Phoenix lineations and the Nova-Canton Trough, or along the Nova-Canton Trough itself, may be due to a decrease in spreading rate prior to

SWIFT X-RAY OBSERVATIONS OF CLASSICAL NOVAE. II. THE SUPER SOFT SOURCE SAMPLE

Energy Technology Data Exchange (ETDEWEB)

Schwarz, Greg J. [American Astronomical Society, 2000 Florida Avenue, NW, Suite 400, Washington, DC 20009-1231 (United States); Ness, Jan-Uwe [XMM-Newton Science Operations Centre, ESAC, Apartado 78, 28691 Villanueva de la Canada, Madrid (Spain); Osborne, J. P.; Page, K. L.; Evans, P. A.; Beardmore, A. P. [Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH (United Kingdom); Walter, Frederick M. [Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794-3800 (United States); Andrew Helton, L. [SOFIA Science Center, USRA, NASA Ames Research Center, M.S. N211-3, Moffett Field, CA 94035 (United States); Woodward, Charles E. [Minnesota Institute of Astrophysics, 116 Church Street S.E., University of Minnesota, Minneapolis, MN 55455 (United States); Bode, Mike [Astrophysics Research Institute, Liverpool John Moores University, Birkenhead CH41 1LD (United Kingdom); Starrfield, Sumner [School of Earth and Space Exploration, Arizona State University, P.O. Box 871404, Tempe, AZ 85287-1404 (United States); Drake, Jeremy J., E-mail: Greg.Schwarz@aas.org [Smithsonian Astrophysical Observatory, 60 Garden Street, MS 3, Cambridge, MA 02138 (United States)

2011-12-01

The Swift gamma-ray burst satellite is an excellent facility for studying novae. Its rapid response time and sensitive X-ray detector provides an unparalleled opportunity to investigate the previously poorly sampled evolution of novae in the X-ray regime. This paper presents Swift observations of 52 Galactic/Magellanic Cloud novae. We included the X-Ray Telescope (0.3-10 keV) instrument count rates and the UltraViolet and Optical Telescope (1700-8000 A) filter photometry. Also included in the analysis are the publicly available pointed observations of 10 additional novae the X-ray archives. This is the largest X-ray sample of Galactic/Magellanic Cloud novae yet assembled and consists of 26 novae with Super Soft X-ray emission, 19 from Swift observations. The data set shows that the faster novae have an early hard X-ray phase that is usually missing in slower novae. The Super Soft X-ray phase occurs earlier and does not last as long in fast novae compared to slower novae. All the Swift novae with sufficient observations show that novae are highly variable with rapid variability and different periodicities. In the majority of cases, nuclear burning ceases less than three years after the outburst begins. Previous relationships, such as the nuclear burning duration versus t{sub 2} or the expansion velocity of the eject and nuclear burning duration versus the orbital period, are shown to be poorly correlated with the full sample indicating that additional factors beyond the white dwarf mass and binary separation play important roles in the evolution of a nova outburst. Finally, we confirm two optical phenomena that are correlated with strong, soft X-ray emission which can be used to further increase the efficiency of X-ray campaigns.

SWIFT X-RAY OBSERVATIONS OF CLASSICAL NOVAE. II. THE SUPER SOFT SOURCE SAMPLE

International Nuclear Information System (INIS)

Schwarz, Greg J.; Ness, Jan-Uwe; Osborne, J. P.; Page, K. L.; Evans, P. A.; Beardmore, A. P.; Walter, Frederick M.; Andrew Helton, L.; Woodward, Charles E.; Bode, Mike; Starrfield, Sumner; Drake, Jeremy J.

2011-01-01

The Swift gamma-ray burst satellite is an excellent facility for studying novae. Its rapid response time and sensitive X-ray detector provides an unparalleled opportunity to investigate the previously poorly sampled evolution of novae in the X-ray regime. This paper presents Swift observations of 52 Galactic/Magellanic Cloud novae. We included the X-Ray Telescope (0.3-10 keV) instrument count rates and the UltraViolet and Optical Telescope (1700-8000 Å) filter photometry. Also included in the analysis are the publicly available pointed observations of 10 additional novae the X-ray archives. This is the largest X-ray sample of Galactic/Magellanic Cloud novae yet assembled and consists of 26 novae with Super Soft X-ray emission, 19 from Swift observations. The data set shows that the faster novae have an early hard X-ray phase that is usually missing in slower novae. The Super Soft X-ray phase occurs earlier and does not last as long in fast novae compared to slower novae. All the Swift novae with sufficient observations show that novae are highly variable with rapid variability and different periodicities. In the majority of cases, nuclear burning ceases less than three years after the outburst begins. Previous relationships, such as the nuclear burning duration versus t 2 or the expansion velocity of the eject and nuclear burning duration versus the orbital period, are shown to be poorly correlated with the full sample indicating that additional factors beyond the white dwarf mass and binary separation play important roles in the evolution of a nova outburst. Finally, we confirm two optical phenomena that are correlated with strong, soft X-ray emission which can be used to further increase the efficiency of X-ray campaigns.

21 CFR 884.6200 - Assisted reproduction laser system.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Assisted reproduction laser system. 884.6200... (CONTINUED) MEDICAL DEVICES OBSTETRICAL AND GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6200 Assisted reproduction laser system. (a) Identification. The assisted reproduction laser system is a device...

Three-dimensional simulations of the interaction between the nova ejecta, accretion disk, and companion star

Science.gov (United States)

Figueira, Joana; José, Jordi; García-Berro, Enrique; Campbell, Simon W.; García-Senz, Domingo; Mohamed, Shazrene

2018-05-01

Context. Classical novae are thermonuclear explosions hosted by accreting white dwarfs in stellar binary systems. Material piles up on top of the white dwarf star under mildly degenerate conditions, driving a thermonuclear runaway. The energy released by the suite of nuclear processes operating at the envelope, mostly proton-capture reactions and β+-decays, heats the material up to peak temperatures ranging from 100 to 400 MK. In these events, about 10-3-10-7 M⊙, enriched in CNO and, sometimes, other intermediate-mass elements (e.g., Ne, Na, Mg, and Al) are ejected into the interstellar medium. Aims: To date, most of the efforts undertaken in the modeling of classical nova outbursts have focused on the early stages of the explosion and ejection, ignoring the interaction of the ejecta, first with the accretion disk orbiting the white dwarf and ultimately with the secondary star. Methods: A suite of 3D, smoothed-particle hydrodynamics (SPH) simulations of the interaction between the nova ejecta, accretion disk, and stellar companion were performed to fill this gap; these simulations were aimed at testing the influence of the model parameters—that is, the mass and velocity of the ejecta, mass and the geometry of the accretion disk—on the dynamical and chemical properties of the system. Results: We discuss the conditions that lead to the disruption of the accretion disk and to mass loss from the binary system. In addition, we discuss the likelihood of chemical contamination of the stellar secondary induced by the impact with the nova ejecta and its potential effect on the next nova cycle. Movies showing the full evolution of several models are available online at http://https://www.aanda.org and at http://www.fen.upc.edu/users/jjose/Downloads.html

Repetitive output laser system and method using target reflectivity

International Nuclear Information System (INIS)

Johnson, R.R.

1978-01-01

An improved laser system and method for implosion of a thermonuclear fuel pellet is described in which that portion of a laser pulse reflected by the target pellet is utilized in the laser system to initiate a succeeding target implosion, and in which the energy stored in the laser system to amplify the initial laser pulse, but not completely absorbed thereby, is used to amplify succeeding laser pulses initiated by target refγlection

Observations and predictions of EUV emission from classical novae

International Nuclear Information System (INIS)

Starrfield, S.; Truran, J.W.; Sparks, W.M.; Krautter, J.

1989-01-01

Theoretical modeling of novae in outburst predicts that they should be active emitters of radiation both in the EUV and soft X-ray wavelengths twice during the outburst. The first time is very early in the outburst when only an all sky survey can detect them. This period lasts only a few hours. They again become bright EUV and soft X-ray emitters late in the outburst when the remnant object becomes very hot and is still luminous. The predictions imply both that a nova can remain very hot for months to years and that the peak temperature at this time strongly depends upon the mass of the white dwarf. It is important to observe novae at these late times because a measurement of both the flux and temperature can provide information about the mass of the white dwarf, the tun-off time scale, and the energy budget of the outburst. We review the existing observations of novae in late stages of their outburst and present some newly obtained data for GQ Mus 1983. We then provide results of new hydrodynamic simulations of novae in outburst and compare the predictions to the observations. 43 refs., 6 figs

Eruptions and superhumps in dwarf novae

International Nuclear Information System (INIS)

Patterson, J.

1979-01-01

The existence of two distinct eruption types in dwarf novae is considered. A small subclass of dwarf novae, the SU Ursae Majoris stars, show occasional very bright and long eruptions (''supermaxima''), and during supermaxima, large-amplitude photometric variations (''superhumps'') at a period related to the orbital period are seen. Two new stars showing these effects, AY Lyrae and YZ Cancri, are reported. A third star, WZ Sagittae, is probably also a member of the class. Models for the superhumps are reviewed and found to be unsatisfactory. Observational constraints on a successful model are discussed

Spectral evolution of dwarf nova outbursts

International Nuclear Information System (INIS)

Cannizzo, J.K.; Kenyon, S.J.

1987-01-01

The disk instability model for dwarf nova eruptions is investigated by computing the spectral development of the accretion disk through a complete limit cycle. Observed stellar spectra are used to model the radiation emitted by optically thick annuli within the disc. The general findings agree with those of Smak (1984) and Pringle et al. (1986). It is suggested that the dwarf nova oscillations might be a source of information concerning the evolution of the inner disk and that detailed observations of this phenomenon can be used to test various outburst mechanisms. 74 references

Application of a Terrestrial LIDAR System for Elevation Mapping in Terra Nova Bay, Antarctica

Directory of Open Access Journals (Sweden)

Hyoungsig Cho

2015-09-01

Full Text Available A terrestrial Light Detection and Ranging (LIDAR system has high productivity and accuracy for topographic mapping, but the harsh conditions of Antarctica make LIDAR operation difficult. Low temperatures cause malfunctioning of the LIDAR system, and unpredictable strong winds can deteriorate data quality by irregularly shaking co-registration targets. For stable and efficient LIDAR operation in Antarctica, this study proposes and demonstrates the following practical solutions: (1 a lagging cover with a heating pack to maintain the temperature of the terrestrial LIDAR system; (2 co-registration using square planar targets and two-step point-merging methods based on extracted feature points and the Iterative Closest Point (ICP algorithm; and (3 a georeferencing module consisting of an artificial target and a Global Navigation Satellite System (GNSS receiver. The solutions were used to produce a topographic map for construction of the Jang Bogo Research Station in Terra Nova Bay, Antarctica. Co-registration and georeferencing precision reached 5 and 45 mm, respectively, and the accuracy of the Digital Elevation Model (DEM generated from the LIDAR scanning data was ±27.7 cm.

Application of a Terrestrial LIDAR System for Elevation Mapping in Terra Nova Bay, Antarctica.

Science.gov (United States)

Cho, Hyoungsig; Hong, Seunghwan; Kim, Sangmin; Park, Hyokeun; Park, Ilsuk; Sohn, Hong-Gyoo

2015-09-16

A terrestrial Light Detection and Ranging (LIDAR) system has high productivity and accuracy for topographic mapping, but the harsh conditions of Antarctica make LIDAR operation difficult. Low temperatures cause malfunctioning of the LIDAR system, and unpredictable strong winds can deteriorate data quality by irregularly shaking co-registration targets. For stable and efficient LIDAR operation in Antarctica, this study proposes and demonstrates the following practical solutions: (1) a lagging cover with a heating pack to maintain the temperature of the terrestrial LIDAR system; (2) co-registration using square planar targets and two-step point-merging methods based on extracted feature points and the Iterative Closest Point (ICP) algorithm; and (3) a georeferencing module consisting of an artificial target and a Global Navigation Satellite System (GNSS) receiver. The solutions were used to produce a topographic map for construction of the Jang Bogo Research Station in Terra Nova Bay, Antarctica. Co-registration and georeferencing precision reached 5 and 45 mm, respectively, and the accuracy of the Digital Elevation Model (DEM) generated from the LIDAR scanning data was ±27.7 cm.

Infrared spectroscopy of the remnant of Nova Sco 2014: a symbiotic star with too little circumstellar matter to decelerate the ejecta

Science.gov (United States)

Munari, U.; Banerjee, D. P. K.

2018-03-01

Pre-outburst 2MASS and WISE photometry of Nova Sco 2014 (V1534 Sco) has suggested the presence of a cool giant at the location of the nova in the sky. The spectral evolution recorded for the nova did not, however, support a direct partnership because no flash-ionized wind and no deceleration of the ejecta were observed, contrary to the behaviour displayed by other novae which erupted within symbiotic binaries like V407 Cyg or RS Oph. We have therefore obtained 0.8-2.5 μm spectra of the remnant of Nova Sco 2014 in order to ascertain if a cool giant is indeed present and if it is physically associated with the nova. The spectrum shows the presence of a M6III giant, reddened by E(B - V) = 1.20, displaying the typical and narrow emission-line spectrum of a symbiotic star, including He I 1.0830 μm with a deep P-Cyg profile. This makes Nova Sco 2014 a new member of the exclusive club of novae that erupt within a symbiotic binary. Nova Sco 2014 shows that a nova erupting within a symbiotic binary does not always come with a deceleration of the ejecta, contrary to the common belief. Many other similar systems may lay hidden in past novae, especially in those that erupted prior to the release of the 2MASS all-sky infrared survey, which could be profitably cross-matched now against them.

Spectroscopy of poorly known northern dwarf novae. Part. I

International Nuclear Information System (INIS)

Bruch, A.

1989-01-01

Spectroscopic observations of 12 dwarf novae are presented most of which hitherto unknown spectroscopically. The classifications as dwarf novae could be confirmed in most cases. Two objects remain doubtful: CI UMa and MR Per. The latter has the spectrum of a very late type main sequence star with hydrogen emissions and might be a flare star showing extremely slow flares, while the CI UMa spectrum does not contain any emission line above the noise level. In two dwarf novae - DX And and NS Per - absorption lines of the secondary star are newly detected

Laser surveillance system for spent fuel

International Nuclear Information System (INIS)

Fiarman, S.; Zucker, M.S.; Bieber, A.M. Jr.

1980-01-01

A laser surveillance system installed at spent fuel storage pools will provide the safeguard inspector with specific knowledge of spent fuel movement that cannot be obtained with current surveillance systems. The laser system will allow for the division of the pool's spent fuel inventory into two populations - those assemblies which have been moved and those which haven't - which is essential for maximizing the efficiency and effectiveness of the inspection effort. We have designed, constructed, and tested a laser system and have used it with a simulated BWR assembly. The reflected signal from the zircaloy rods depends on the position of the assembly, but in all cases is easily discernable from the reference scan of background with no assembly

Rate of nova production in the Galaxy

International Nuclear Information System (INIS)

Liller, W.; Mayer, B.; PROBLICOM Sky Survey, Los Angeles, CA)

1987-01-01

The ongoing PROBLICOM program in the Southern Hemisphere now makes it possible to derive a reliable value for the overall production rate of Galactic novae. The results, 73 + or - 24/y, indicates that the Galaxy outproduces M 31 by a factor of two or three. It is estimated that the rate of supernova ejecta is one and a half orders of magnitude greater than that of novae in the Galaxy. 15 references

A theoretical study of problems in classical nova evolution

International Nuclear Information System (INIS)

Shankar, A.

1990-01-01

Three distinct issues in classical nova evolution are addressed with the aid of one- and two-dimensional numerical hydrodynamics. The effects of convection on nova outbursts are examined within the confines of the mixing length theory. It is found that increasing the efficiency of convection enhances the violence of the thermonuclear runaway (TNR). This also relates to the question of the feasibility of obtaining nova outbursts on magnetic white dwarfs among the AM Her systems. The effects of a strong magnetic field on the TNR are explored. The field interferes with the development of convection during the TNR, which results in lower ejection velocities. However, for field strengths typical of cataclysmic variables, the violence of strong outbursts is affected only moderately. The conditions necessary for the production of strong TNR's in the hibernation model of cataclysmic binary evolution are also examined. The feasibility of obtaining strong nova outbursts is investigated when the accretion rate during hibernation is decreased. It is found that a reduction (by a factor of 100) for periods of longer than a couple thousand years, is sufficient to ensure violent outbursts, even in the presence of large pre-outburst accretion rates. The effects of a common envelope phase (CEP) on the outburst are discussed. The motion of the secondary through an expanding common envelope is resisted by frictional drag. This dissipates both energy and angular momentum from the orbit inducing hydrodynamic motion. Significant departures are found to occur in the manner in which mass is lost when the effects of drag are taken into account. Specifically, a CEP is found to accelerate and enhance mass loss. Ejection is found to be concentrated in the orbital plane, with velocities of a few thousand km/sec

Results of Statewide TerraNova Testing, Fall 1998.

Science.gov (United States)

La Marca, Paul M.

This summary provides key findings about state, district, and school level performance on the TerraNova examinations (CTB/McGraw Hill) in Nevada in 1998-1999. The TerraNova tests are used to assess students in grades 4, 8, and 10 as stipulated by Nevada law. Within this summary, a description of performance as measured by national percentile…

High-energy Emission from Nonrelativistic Radiative Shocks: Application to Gamma-Ray Novae

Science.gov (United States)

Vurm, Indrek; Metzger, Brian D.

2018-01-01

The observation of GeV gamma-rays from novae by Fermi/LAT demonstrates that the nonrelativistic radiative shocks in these systems can accelerate particles to energies of at least ∼10 GeV. The low-energy extension of the same nonthermal particle distribution inevitably gives rise to emission in the hard X-ray band. Above ≳ 10 {keV}, this radiation can escape the system without significant absorption/attenuation, and can potentially be detected by NuSTAR. We present theoretical models for hard X-ray and gamma-ray emission from radiative shocks in both leptonic and hadronic scenarios, accounting for the rapid evolution of the downstream properties due to the fast cooling of thermal plasma. We find that due to strong Coulomb losses, only a fraction of {10}-4{--}{10}-3 of the gamma-ray luminosity is radiated in the NuSTAR band; nevertheless, this emission could be detectable simultaneously with the LAT emission in bright gamma-ray novae with a ∼50 ks exposure. The spectral slope in hard X-rays is α ≈ 0 for typical nova parameters, thus serving as a testable prediction of the model. Our work demonstrates how combined hard X-ray and gamma-ray observations can be used to constrain properties of the nova outflow (velocity, density, and mass outflow rate) and particle acceleration at the shock. A very low X-ray to gamma-ray luminosity ratio ({L}{{X}}/{L}γ ≲ 5× {10}-4) would disfavor leptonic models for the gamma-ray emission. Our model can also be applied to other astrophysical environments with radiative shocks, including SNe IIn and colliding winds in massive star binaries.

A Recurrent Nova Super-Remnant in the Andromeda Galaxy

DEFF Research Database (Denmark)

Darnley, M. J.; Hounsell, R.; O'Brien, T. J.

2017-01-01

Here we report that the most rapidly recurring nova, M31N 2008-12a, which erupts annually, is surrounded by a "nova super-remnant" which demonstrates that M31N 2008-12a has erupted with high frequency for millions of years....

Improvements of the ruby laser oscillator system for laser scattering

International Nuclear Information System (INIS)

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

1978-10-01

A ruby laser oscillator system is used to measure electron temperatures of the Tokamak plasmas(JFT-2 and JFT-2a). Improvements have been made of the laser oscillator to obtain the correct values. Described are the improvements and the damages of a ruby rod and a KD*P crystal for Q-switching by laser beam. Improvement are the linear Xe lamp replaced by a helical Xe lamp and in the electrical circuit for Q-switching. The damage of an optical component by a laser beam should be clarified from the damage data; the cause is not found yet. (author)

NOVAS TECNOLOGIAS NO ENVELHECIMENTO

Directory of Open Access Journals (Sweden)

Rosa Maria Farah

2010-02-01

Full Text Available O Programa de Estudos Pós-Graduados em Gerontologia/PUC-SP desenvolve pesquisas em diversificadas linhas algumas das quais têm em comum o acolhimento à questão das novas tecnologias no envelhecimento. São investigações de caráter interdisciplinar que envolvem docentes-pesquisadores, orientandos de mestrado e de iniciação científica. Na área da educação a distância, a PUC-SP inaugura um trabalho em que o idoso interessado em avançar em seus conhecimentos é recebido em um ambiente virtual de aprendizagem, em que pode participar de cursos avançados de aquisição de novas linguagens e de navegação na Internet, cujas consequências são o investimento em uma via mais digna para o envelhecer no sentido de esse idoso sentir-se um ser ligado aos novos tempos em que a interatividade digital traz-lhe possibilidades ilimitadas de contatos com o outro, com o mundo enfim. A pesquisa sobre a inclusão cibersocial do idoso mostra o que significa colocar o idoso em contato com a Internet, quando este recebe, por meio das redes sociais, ofertas de várias ordens, e equipamentos que contornam limitações de ordem física ou motora. Além disso, o registro digital da memória do idoso, de sua história e referências também podem constituir conteudos preciosos para pesquisas. A relação do idoso com a informática pode situá-lo como um ator, produtor e reprodutor no ciberespaço. Isso significa que as vantagens do uso do computador fazem o idoso ganhar novo sentido na vida, na medida em que pode assim preencher o vazio causado pelas perdas que lhe vão ocorrendo, possibilitando que ele redimensione seu olhar para o presente e futuro. Palavras-chave: o sujeito-idoso nas novas tecnologias; novas tecnologias e envelhecimento; o idoso na educação a distância; internet na velhice.

Optical evolution of Nova Ophiuchi 2007 = V2615 Oph

Science.gov (United States)

Munari, U.; Henden, A.; Valentini, M.; Siviero, A.; Dallaporta, S.; Ochner, P.; Tomasoni, S.

2008-06-01

The moderately fast Nova Oph 2007 reached maximum brightness on 2007 March 28 at V= 8.52, B-V=+1.12, V-RC=+0.76, V-IC=+1.59 and RC-IC=+0.83, after fast initial rise and a pre-maximum halt lasting a week. Decline times were tV2= 26.5, tB2= 30, tV3= 48.5 and tB3= 56.5 d. The distance to the nova is d= 3.7 ± 0.2 kpc, the height above the Galactic plane is z= 215 pc, the reddening is E(B-V) = 0.90 and the absolute magnitude at maximum is MmaxV=-7.2 and MmaxB=-7.0. The spectrum four days before maximum resembled a F6 supergiant, in an agreement with broad-band colours. It later developed into that of a standard `Fe ii'-class nova. Nine days past maximum, the expansion velocity estimated from the width of Hα emission component was ˜730 km s-1, and the displacement from it of the principal and diffuse-enhanced absorption systems was ˜650 and 1380 km s-1, respectively. Dust probably formed and disappeared during the period from 82 to 100 d past maximum, causing (at peak dust concentration) an extinction of ΔB= 1.8 mag and an extra ΔE(B-V) = 0.44 reddening.

Problems in the development of autonomous mobile laser systems based on a cw chemical DF laser

International Nuclear Information System (INIS)

Aleksandrov, B P; Bashkin, A S; Beznozdrev, V N; Parfen'ev, M V; Pirogov, N A; Semenov, S N

2003-01-01

The problems involved in designing autonomous mobile laser systems based on high-power cw chemical DF lasers, whose mass and size parameters would make it possible to install them on various vehicles, are discussed. The need for mobility of such lasers necessitates special attention to be paid to the quest for ways and means of reducing the mass and size of the main laser systems. The optimisation of the parameters of such lasers is studied for various methods of scaling their systems. A complex approach to analysis of the optical scheme of the laser system is developed. (special issue devoted to the 80th anniversary of academician n g basov's birth)

What does an erupting nova do to its red dwarf companion?

International Nuclear Information System (INIS)

Kovetz, A.; Prialnik, D.; Shara, M.M.

1988-01-01

During nova eruptions and for decades afterward, the red dwards in cataclysmic binaries are irradiated with hundreds of times more luminosity than they themselves produce. Simulations of the time-dependent irradiation of three red dwarf models (0.25, 0.50, and 0.75 solar mass) are presented. The mass transfer rates forced by irradiation after nova eruption are found to be enhanced by two orders of magnitude because of the irradiation. The time scale for irradiation to become unimportant is that of the white dwarf cooling time scale, a few centuries. These two results support the hibernation scenario of novae, which suggests that novae remain bright for a few centuries after eruption because of irradiation-induced mass transfer. After irradiation decreases mass transfer slows, and some very old novae may then become extremely faint. 26 references

Near-infrared and optical studies of the highly obscured nova V1831 Aquilae (Nova Aquilae 2015)

Science.gov (United States)

Banerjee, D. P. K.; Srivastava, Mudit K.; Ashok, N. M.; Munari, U.; Hambsch, F.-J.; Righetti, G. L.; Maitan, A.

2018-01-01

Near-infrared (NIR) and optical photometry and spectroscopy are presented for the nova V1831 Aquilae, covering the early decline and dust-forming phases during the first ∼90 d after its discovery. The nova is highly reddened due to interstellar extinction. Based solely on the nature of the NIR spectrum, we are able to classify the nova to be of the Fe II class. The distance and extinction to the nova are estimated to be 6.1 ± 0.5 kpc and Av ∼ 9.02, respectively. Lower limits of the electron density, emission measure and ionized ejecta mass are made from a Case B analysis of the NIR Brackett lines, while the neutral gas mass is estimated from the optical [O I] lines. We discuss the cause of the rapid strengthening of the He I 1.0830-μm line during the early stages. V1831 Aql formed a modest amount of dust fairly early (∼19.2 d after discovery); the dust shell is not seen to be optically thick. Estimates of the dust temperature, dust mass and grain size are made. Dust formation commences around day 19.2 at a condensation temperature of 1461 ± 15 K, suggestive of a carbon composition, following which the temperature is seen to decrease gradually to 950 K. The dust mass shows a rapid initial increase, which we interpret as being due to an increase in the number of grains, followed by a period of constancy, suggesting the absence of grain destruction processes during this latter time. A discussion of the evolution of these parameters is made, including certain peculiarities seen in the grain radius evolution.

System for combining laser beams of diverse frequencies

International Nuclear Information System (INIS)

1980-01-01

A system is described for combining laser beams of different frequencies into a number of beams each comprising laser radiation having components of each of the different frequencies. The system can be used in laser isotope separation facilities. (U.K.)

Orbital periods of recurrent novae

International Nuclear Information System (INIS)

Schaefer, B.E.

1990-01-01

The class of recurrent novae (RN) with thermonuclear runaways contains only three systems (T Pyx, U Sco, and V394 CrA), for which no orbital periods are known. This paper presents a series of photometric observations where the orbital periods for all three systems are discovered. T Pyx is found to have sinusoidal modulation with an amplitude of 0.08 mag and a period of 2.3783 h (with a possible alias of 2.6403 h). U Sco is found to be an eclipsing system with an eclipse amplitude of roughly 1.5 mag and an orbital period of 1.2344 days. V394 CrA is found to have sinusoidal modulation with an amplitude of 0.5 mag and a period of 0.7577 days. Thus two out of three RN with thermonuclear runaways (or five out of six for all RN) have evolved companions. 16 refs

Modematic: a fast laser beam analyzing system for high power CO2-laser beams

Science.gov (United States)

Olsen, Flemming O.; Ulrich, Dan

2003-03-01

The performance of an industrial laser is very much depending upon the characteristics of the laser beam. The ISO standards 11146 and 11154 describing test methods for laser beam parameters have been approved. To implement these methods in industry is difficult and especially for the infrared laser sources, such as the CO2-laser, the availabl analyzing systems are slow, difficult to apply and having limited reliability due to the nature of the detection methods. In an EUREKA-project the goal was defined to develop a laser beam analyzing system dedicated to high power CO2-lasers, which could fulfill the demands for an entire analyzing system, automating the time consuming pre-alignment and beam conditioning work required before a beam mode analyses, automating the analyzing sequences and data analysis required to determine the laser beam caustics and last but not least to deliver reliable close to real time data to the operator. The results of this project work will be described in this paper. The research project has led to the development of the Modematic laser beam analyzer, which is ready for the market.

Multiplex electric discharge gas laser system

Science.gov (United States)

Laudenslager, James B. (Inventor); Pacala, Thomas J. (Inventor)

1987-01-01

A multiple pulse electric discharge gas laser system is described in which a plurality of pulsed electric discharge gas lasers are supported in a common housing. Each laser is supplied with excitation pulses from a separate power supply. A controller, which may be a microprocessor, is connected to each power supply for controlling the application of excitation pulses to each laser so that the lasers can be fired simultaneously or in any desired sequence. The output light beams from the individual lasers may be combined or utilized independently, depending on the desired application. The individual lasers may include multiple pairs of discharge electrodes with a separate power supply connected across each electrode pair so that multiple light output beams can be generated from a single laser tube and combined or utilized separately.

Modelling the structure and kinematics of the Firework nebula: The nature of the GK Persei nova shell and its jet-like feature

Science.gov (United States)

Harvey, E.; Redman, M. P.; Boumis, P.; Akras, S.

2016-10-01

Aims: The shaping mechanisms of old nova remnants are probes for several important and unexplained processes, such as dust formation and the structure of evolved star nebulae. To gain a more complete understanding of the dynamics of the GK Per (1901) remnant, an examination of symmetry of the nova shell is explored, followed by a kinematical analysis of the previously detected jet-like feature in the context of the surrounding fossil planetary nebula. Methods: Faint-object high-resolution echelle spectroscopic observations and imaging were undertaken covering the knots which comprise the nova shell and the surrounding nebulosity. New imaging from the Aristarchos telescope in Greece and long-slit spectra from the Manchester Echelle Spectrometer instrument at the San Pedro Mártir observatory in Mexico were obtained, supplemented with archival observations from several other optical telescopes. Position-velocity arrays are produced of the shell, and also individual knots, and are then used for morpho-kinematic modelling with the shape code. The overall structure of the old knotty nova shell of GK Per and the planetary nebula in which it is embedded is then analysed. Results: Evidence is found for the interaction of knots with each other and with a wind component, most likely the periodic fast wind emanating from the central binary system. We find that a cylindrical shell with a lower velocity polar structure gives the best model fit to the spectroscopy and imaging. We show in this work that the previously seen jet-like feature is of low velocity. Conclusions: The individual knots have irregular tail shapes; we propose here that they emanate from episodic winds from ongoing dwarf nova outbursts by the central system. The nova shell is cylindrical, not spherical, and the symmetry axis relates to the inclination of the central binary system. Furthermore, the cylinder axis is aligned with the long axis of the bipolar planetary nebula in which it is embedded. Thus, the

Late-type components of slow novae and symbiotic stars

Energy Technology Data Exchange (ETDEWEB)

Allen, D A [Anglo-Australian Observatory, Epping (Australia); Royal Observatory, Edinburgh (UK))

1980-08-01

It is argued that the various types of symbiotic stars and the slow novae are the same phenomena exhibiting a range of associated time-scales, the slow novae being of intermediate speed. Evidence is summarized showing that both types of object contain normal M giants or mira variables. This fact is at odds with currently fashionable single-star models for slow novae, according to which the M star is totally disrupted before the outburst. Spectral types of the late-type components are presented for nearly 80 symbiotic stars and slow novae, derived from 2 ..mu..m spectroscopy. It is found that both the intensity of the emission spectrum and the electron density of the gas are functions of the spectral type of the late-type star. Explanations for these correlations are given. On the assumption that the late-type components are normal giants, spectroscopic parallaxes are determined; credible distances are derived which indicate that the known symbiotic stars have been sampled as far afield as the Galactic Centre. Hydrogen shell flashes on a white dwarf accreting gas from the late-type components offer an attractive explanation of the phenomena of slow novae and symbiotic stars, and such models are discussed in the concluding section.

Canada-Nova Scotia Offshore Petroleum Board annual report, 1992-1993

International Nuclear Information System (INIS)

1993-06-01

The Canada-Nova Scotia Offshore Petroleum Board was established as the agency responsible for the regulation of the hydrocarbon resources in the Nova Scotia offshore. The Board evaluates resource potential, administers petroleum exploration and production rights, approves offshore activities, and approves benefits and development plans. The main activities of the Board in 1992-1993 are summarized and financial statements are presented. Highlights include production of 572,300 m 3 of oil during the first production season of LASMO Nova Scotia Ltd.'s Cohasset development, the first commercial offshore oil production for Canada; four major resource evaluation projects in the Glenelg Field, the Laurentian sub-basin, the Fundy Rift Basin, and the Panuke Field; holding of discussions between Nova Scotia, Newfoundland, and Canada on the maritime boundary lines between respective offshore petroleum board jurisdictions, in the wake of a June 1992 determination of the disputed maritime boundary around St. Pierre et Miquelon; and amendments of certain safety-related legislation applicable to offshore operations. Employment benefits of the Cohasset project during 1992 totalled ca 470 Nova Scotians and 120 other Canadians. 3 tabs

Laser and photonic systems design and integration

CERN Document Server

Nof, Shimon Y; Cheng, Gary J

2014-01-01

New, significant scientific discoveries in laser and photonic technologies, systems perspectives, and integrated design approaches can improve even further the impact in critical areas of challenge. Yet this knowledge is dispersed across several disciplines and research arenas. Laser and Photonic Systems: Design and Integration brings together a multidisciplinary group of experts to increase understanding of the ways in which systems perspectives may influence laser and photonic innovations and application integration.By bringing together chapters from leading scientists and technologists, ind

X-ray novae - what are they

International Nuclear Information System (INIS)

Wennfors, B.

1976-01-01

Ten of the two hundred cosmic X-ray sources exhibit characteristics in their emissions analogous to novae, i.e. after a rapid increase in luminosity, lasting about three days, follows a period of about a month with a slow decrease, and thereafter a rapid decrease to invisibility. The spectra of such sources are discussed in general terms and brief descriptions are given of the five which have been identified with optical objects. Three models for the history of X-ray novae, all based on X-ray emission from a compact object in an orbit very near a larger star, are discussed. (JIW)

Observations and simulations of recurrent novae: U Sco and V394 CrA

Science.gov (United States)

Starrfield, S.; Sonneborn, G.; Sparks, Warren M.; Shaviv, G.; Williams, R. E.; Heathcote, S.; Ferland, Gary; Gehrz, Robert D.; Ney, Edward P.; Kenyon, Scott

1988-01-01

Observations and analysis of the Aug. 1987 outburst of the recurrent nova V394 CrA are presented. This nova is extremely fast and its outburst characteristics closely resemble those of the recurrent nova U Sco. Hydrodynamic simulations of the outbursts of recurrent novae were performed. Results as applied to the outbursts of V394 CrA and U Sco are summarized.

THE INTER-ERUPTION TIMESCALE OF CLASSICAL NOVAE FROM EXPANSION OF THE Z CAMELOPARDALIS SHELL

International Nuclear Information System (INIS)

Shara, Michael M.; Mizusawa, Trisha; Zurek, David; Martin, Christopher D.; Neill, James D.; Seibert, Mark

2012-01-01

The dwarf nova Z Camelopardalis is surrounded by the largest known classical nova shell. This shell demonstrates that at least some dwarf novae must have undergone classical nova eruptions in the past, and that at least some classical novae become dwarf novae long after their nova thermonuclear outbursts. The current size of the shell, its known distance, and the largest observed nova ejection velocity set a lower limit to the time since Z Cam's last outburst of 220 years. The radius of the brightest part of Z Cam's shell is currently ∼880 arcsec. No expansion of the radius of the brightest part of the ejecta was detected, with an upper limit of ≤0.17 arcsec yr –1 . This suggests that the last Z Cam eruption occurred ≥5000 years ago. However, including the important effect of deceleration as the ejecta sweeps up interstellar matter in its snowplow phase reduces the lower limit to 1300 years. This is the first strong test of the prediction of nova thermonuclear runaway theory that the interoutburst times of classical novae are longer than 1000 years. The intriguing suggestion that Z Cam was a bright nova, recorded by Chinese imperial astrologers in October-November 77 B.C.E., is consistent with our measurements. If Z Cam was indeed the nova of 77 B.C.E. we predict that its ejecta are currently expanding at 85 km s –1 , or 0.11 arcsec yr –1 . Detection and measurement of this rate of expansion should be possible in just a few years.

Experimental study of the 22Ne(p,γ)23Na reaction and its implications for novae scenarios

International Nuclear Information System (INIS)

Menzel, Marie-Luise

2013-01-01

The 22 Ne(p,γ) 23 Na reaction belongs to the catalytic neon-sodium cycle and has an important role in the explosive hydrogen burning. The neon-sodium cycle takes place at temperatures of T = 0.1 - 0.5 GK and is assumed to occur in different astrophysical systems: e.g. in novae, in super novae of type Ia and during the shell-burning of red giant branch stars. The implications of 22 Ne(p,γ) 23 Na and the neon-sodium cycle in a nova scenario have been studied by using the nuclear network code libnucnet at GSI in Darmstadt. A nova is an outburst of matter in a binary system consisting of a white dwarf and a red giant star. It is therefore a representative phenomenon for explosive hydrogen burning. For the calculation of the nucleosynthesis during the nova outburst, the code libnucnet requires the initial mass composition of the novae partners, the temperature and density profiles of the nova explosion and the thermonuclear reaction rates of the participating reactions. In the following, the code determined the flow and the final atomic abundance in the neon-sodium cycle during the entire nova process. Additionally, the influence of the temperature profile of the novae outburst as well as the thermonuclear reaction rate of the 22 Ne(p,γ) 23 Na reaction on the final atomic abundance in the outburst has been studied. A characteristic measure for the reactions in astrophysical environments is the thermonuclear reaction rate. The reaction rate of 22 Ne(p,γ) 23 Na has still strong uncertainties in the temperature range of T = 0.03 - 0.3 GK. These uncertainties are based on insufficient upper limits of the resonance strengths as well as the possible existence of tentative states that are populated in the energy range of E lab p = 30 - 300 keV. The research presented in this thesis is dedicated to the experimental study of the 22 Ne(p,γ) 23 Na reaction for an improved determination of the thermonuclear reaction rate. Furthermore, the implications of 22 Ne(p,γ) 23 Na and

The dwarf novae WX Hyi and V436 Cen

International Nuclear Information System (INIS)

Bailey, J.

1979-01-01

High speed photometric observations of the dwarf novae WX Hydri and V436 Centauri are presented. WX Hyi was observed during a supermaximum, and showed 'superhumps' repeating with a period of 111 min, similar to those observed in a number of similar systems. Neither WX Hyi nor V436 Cen show any periodic modulation in their quiescent state light curves. (author)

Lasers in tattoo and pigmentation control: role of the PicoSure(®) laser system.

Science.gov (United States)

Torbeck, Richard; Bankowski, Richard; Henize, Sarah; Saedi, Nazanin

2016-01-01

The use of picosecond lasers to remove tattoos has greatly improved due to the long-standing outcomes of nanosecond lasers, both clinically and histologically. The first aesthetic picosecond laser available for this use was the PicoSure(®) laser system (755/532 nm). Now that a vast amount of research on its use has been conducted, we performed a comprehensive review of the literature to validate the continued application of the PicoSure(®) laser system for tattoo removal. A PubMed search was conducted using the term "picosecond" combined with "laser", "dermatology", and "laser tattoo removal". A total of 13 articles were identified, and ten of these met the inclusion criteria for this review. The majority of studies showed that picosecond lasers are an effective and safe treatment mode for the removal of tattoo pigments. Several studies also indicated potential novel applications of picosecond lasers in the removal of various tattoo pigments (eg, black, red, and yellow). Adverse effects were generally mild, such as transient hypopigmentation or blister formation, and were rarely more serious, such as scarring and/or textural change. Advancements in laser technologies and their application in cutaneous medicine have revolutionized the field of laser surgery. Computational modeling provides evidence that the optimal pulse durations for tattoo ink removal are in the picosecond domain. It is recommended that the PicoSure(®) laser system continue to be used for safe and effective tattoo removal, including for red and yellow pigments.

Laser cutting of irregular shape object based on stereo vision laser galvanometric scanning system

Science.gov (United States)

Qi, Li; Zhang, Yixin; Wang, Shun; Tang, Zhiqiang; Yang, Huan; Zhang, Xuping

2015-05-01

Irregular shape objects with different 3-dimensional (3D) appearances are difficult to be shaped into customized uniform pattern by current laser machining approaches. A laser galvanometric scanning system (LGS) could be a potential candidate since it can easily achieve path-adjustable laser shaping. However, without knowing the actual 3D topography of the object, the processing result may still suffer from 3D shape distortion. It is desirable to have a versatile auxiliary tool that is capable of generating 3D-adjusted laser processing path by measuring the 3D geometry of those irregular shape objects. This paper proposed the stereo vision laser galvanometric scanning system (SLGS), which takes the advantages of both the stereo vision solution and conventional LGS system. The 3D geometry of the object obtained by the stereo cameras is used to guide the scanning galvanometers for 3D-shape-adjusted laser processing. In order to achieve precise visual-servoed laser fabrication, these two independent components are integrated through a system calibration method using plastic thin film target. The flexibility of SLGS has been experimentally demonstrated by cutting duck feathers for badminton shuttle manufacture.

Laser-start-up system for magnetic mirror fusion

International Nuclear Information System (INIS)

Frank, A.M.; Thomas, S.R.; Denhoy, B.S.; Chargin, A.K.

1976-01-01

A CO 2 laser system has been developed at LLL to provide hot start-up plasmas for magnetic mirror fusion experiments. A frozen ammonia pellet is irradiated with a laser power density in excess of 10 13 W/cm 2 in a 50-ns pulse. This system uses commercially available laser systems. Optical components were fabricated both by direct machining and standard techniques. The technologies used in this system are directly applicable to reactor scale systems

Combined laser ultrasonics, laser heating, and Raman scattering in diamond anvil cell system

Science.gov (United States)

Zinin, Pavel V.; Prakapenka, Vitali B.; Burgess, Katherine; Odake, Shoko; Chigarev, Nikolay; Sharma, Shiv K.

2016-12-01

We developed a multi-functional in situ measurement system under high pressure equipped with a laser ultrasonics (LU) system, Raman device, and laser heating system (LU-LH) in a diamond anvil cell (DAC). The system consists of four components: (1) a LU-DAC system (probe and pump lasers, photodetector, and oscilloscope) and DAC; (2) a fiber laser, which is designed to allow precise control of the total power in the range from 2 to 100 W by changing the diode current, for heating samples; (3) a spectrometer for measuring the temperature of the sample (using black body radiation), fluorescence spectrum (spectrum of the ruby for pressure measurement), and Raman scattering measurements inside a DAC under high pressure and high temperature (HPHT) conditions; and (4) an optical system to focus laser beams on the sample and image it in the DAC. The system is unique and allows us to do the following: (a) measure the shear and longitudinal velocities of non-transparent materials under HPHT; (b) measure temperature in a DAC under HPHT conditions using Planck's law; (c) measure pressure in a DAC using a Raman signal; and (d) measure acoustical properties of small flat specimens removed from the DAC after HPHT treatment. In this report, we demonstrate that the LU-LH-DAC system allows measurements of velocities of the skimming waves in iron at 2580 K and 22 GPa.

State of the art of CO laser angioplasty system

Science.gov (United States)

Arai, Tsunenori; Mizuno, Kyoichi; Miyamoto, Akira; Sakurada, Masami; Kikuchi, Makoto; Kurita, Akira; Nakamura, Haruo; Takaoka, Hidetsugu; Utsumi, Atsushi; Takeuchi, Kiyoshi

1994-07-01

A unique percutaneous transluminal coronary angioplasty system new IR therapy laser with IR glass fiber delivery under novel angioscope guidance was described. Carbon monoxide (CO) laser emission of 5 mm in wavelength was employed as therapy laser to achieve precise ablation of atheromatous plaque with a flexible As-S IR glass fiber for laser delivery. We developed the first medical CO laser as well as As-S IR glass fiber cable. We also developed 5.5 Fr. thin angioscope catheter with complete directional manipulatability at its tip. The system control unit could manage to prevent failure irradiations and fiber damages. This novel angioplasty system was evaluated by a stenosis model of mongrel dogs. We demonstrated the usefulness of our system to overcome current issues on laser angioplasty using multifiber catheter with over-the-guidewire system.

Underwater laser imaging system (UWLIS)

Energy Technology Data Exchange (ETDEWEB)

DeLong, M. [Lawrence Livermore National Lab., CA (United States)

1994-11-15

Practical limitations with underwater imaging systems area reached when the noise in the back scattered radiation generated in the water between the imaging system and the target obscures the spatial contrast and resolution necessary for target discovery and identification. The advent of high power lasers operating in the blue-green portion of the visible spectrum (oceanic transmission window) has led to improved experimental illumination systems for underwater imaging. Range-gated and synchronously scanned devices take advantage of the unique temporal and spatial coherence properties of laser radiation, respectively, to overcome the deleterious effects of common volume back scatter.

Constraining Calcium Production in Novae

Science.gov (United States)

Tiwari, Pranjal; C. Fry, C. Wrede Team; A. Chen, J. Liang Collaboration; S. Bishop, T. Faestermann, D. Seiler Collaboration; R. Hertenberger, H. Wirth Collaboration

2017-09-01

Calcium is an element that can be produced by thermonuclear reactions in the hottest classical novae. There are discrepancies between the abundance of Calcium observed in novae and expectations based on astrophysical models. Unbound states 1 MeV above the proton threshold affect the production of Calcium in nova models because they act as resonances in the 38 K(p , γ) 39 Ca reaction present. This work describes an experiment to measure the energies of the excited states of 39 Ca . We will bombard a thin target of 40 Ca with a beam of 22 MeV deuterons, resulting in tritons and 39Ca. We will use a Q3D magnetic spectrograph from the MLL in Garching, Germany to momenta analyze the tritons to observe the excitation energies of the resulting 39 Ca states. Simulations have been run to determine the optimal spectrograph settings. We decided to use a chemically stable target composed of CaF2 , doing so resulted in an extra contaminant, Fluorine, which is dealt with by measuring the background from a LiF target. These simulations have led to settings and targets that will result in the observation of the 39 Ca states of interest with minimal interference from contaminants. Preliminary results from this experiment will be presented. National Sciences and Engineering Research Council of Canada and U.S. National Science Foundation.

A deep optical imaging study of the nebular remnants of classical novae

Science.gov (United States)

Slavin, A. J.; O'Brien, T. J.; Dunlop, J. S.

1995-09-01

An optical imaging study of old nova remnants has revealed previously unobserved features in the shells of 13 classical novae - DQ Her, FH Ser, HR Del, GK Per, V1500 Cyg, T Aur, V533 Her, NQ Vul, V476 Cyg, DK Lac, LV Vul, RW UMi and V450 Cyg. These data indicate a possible correlation between nova speed class and the ellipticity of the resulting remnants - those of faster novae tend to comprise randomly distributed clumps of ejecta superposed on spherically symmetric diffuse material, whilst slower novae produce more structured ellipsoidal remnants with at least one and sometimes several rings of enhanced emission. By measuring the extent of the resolved shells and combining this information with previously published ejection speeds, we use expansion parallax to estimate distances for the 13 novae. Whilst we are able to deduce new information about every nova, it is notable that these observations include the first detections of shells around the old novae V450 Cyg and NQ Vul, and that velocity-resolved images of FH Ser and DQ Her have enabled us to estimate their orbital inclinations. Our observations of DQ Her also show that the main ellipsoidal shell is constricted by three rings and surrounded by a faint halo; this halo contains long tails extending outwards from bright knots, perhaps indicating that during or after outburst a fast inner wind has broken through the fractured principal shell.

The environmental and socio-economic impacts and benefits associated with developing a natural gas distribution system in Nova Scotia

Energy Technology Data Exchange (ETDEWEB)

Buszynski, M.E.; Peacock, T. [Sempra Atlantic Gas Inc., Halifax, NS (Canada)

2000-07-01

The discovery of large natural gas reserves off the Scotian Shelf has resulted in the development and construction of offshore production platforms as well as underwater and onshore pipelines to transport natural gas to markets on the eastern seaboard. A billion-dollar expenditure is proposed to establish a local distribution company to construct and maintain approximately 8000 km of distribution and lateral pipelines in the province of Nova Scotia. The many aspects of the proposed program were described with particular focus on the regulatory hearings. The paper also discussed the different landscapes that will be crossed and the specialized construction techniques that will be used to meet environmental and economic challenges. The mechanisms in place to ensure maximum benefit for Nova Scotians were also discussed. The proposed project was also compared to other local megaprojects in the province such as the Sable Offshore Energy Project and the Interprovincial Pipeline through Nova Scotia and New Brunswick. Some of the successful strategies for implementing benefits plans related to large energy projects were also described. Sempra has been awarded the franchise to distribute natural gas in Nova Scotia. The company has developed a benefits plan that offers significant local involvement in terms of labour and materials. 4 figs.

Performance of the Aurora KrF ICF laser system

International Nuclear Information System (INIS)

Jones, J.E.; Czuchlewski, S.J.; Turner, T.P.; Watt, R.G.; Thomas, S.J.; Netz, D.A.; Tallman, C.R.; Mack, J.M.; Figueira, J.F.

1990-01-01

Because short wavelength lasers are attractive for inertial confinement fusion (ICF), the Department of Energy is sponsoring work at Los Alamos National Laboratory in krypton-fluoride (KrF) laser technology. Aurora is a short-pulse, high-power, KrF laser system. It serves as an end-to-end technology demonstration prototype for large-scale ultraviolet laser systems for short wavelength ICF research. The system employs optical angular multiplexing and serial amplification by electron-beam-driven KrF laser amplifiers. The 1 to 5 ns pulse of the Aurora front end is split into 96 beams which are angularly and temporally multiplexed to produce a 480 ns pulse train for amplification by four KrF laser amplifiers. In the present system configuration half (48) of the amplified pulses are demultiplexed using different optical path lengths and delivered simultaneously to target. This paper discusses how the Aurora laser system has entered the initial operational phase by delivering pulse energies of greater than one kilojoule to target

Nova Gas's pipeline to Asia

International Nuclear Information System (INIS)

Lea, N.

1996-01-01

The involvement of the Calgary-based company NOVA Gas International (NGI) in Malaysia's peninsular gas utilization (PGU) project, was described. Phase I and II of the project involved linking onshore gas processing plants with a natural gas transmission system. Phase III of the PGU project was a gas transmission pipeline that began midway up the west coast of peninsular Malaysia to the Malaysia-Thailand border. The complex 549 km pipeline included route selection, survey and soil investigation, archaeological study, environmental impact assessment, land acquisition, meter-station construction, telecommunication systems and office buildings. NGI was the prime contractor on the project through a joint venture with OGP Technical Services, jointly owned by NGI and Petronas, the Thai state oil company. Much of NGI's success was attributed to excellent interpersonal skills, particularly NGI's ability to build confidence and credibility with its Thai partners

Proceedings of Nova Scotia's 2006 energy research and development forum

International Nuclear Information System (INIS)

2006-01-01

The Nova Scotia 2006 energy research and development forum provided a venue for experts from industry, research institutions and government to discuss how research and development will shape the future of energy in the province. The forum was divided into 3 sessions: (1) building knowledge about the marine environment, (2) building knowledge about geoscience, and (3) building knowledge about sustainable energy. A wide ranges of issues related to the Nova Scotia region included whale identification; fisheries mapping; the commercialization of hydrocarbon discoveries; carbon capture and storage and petroleum system analysis and prospect evaluation. Keynote addresses were presented on produced water in Norway; deepwater exploration in Morocco; renewable energy and Canada's role as an energy superpower. The conference featured more than 57 presentations, of which 4 have been catalogued separately for inclusion in this database. refs., tabs., figs

Laser-based agriculture system

KAUST Repository

Ooi, Boon S.

2016-03-31

A system and method are provided for indoor agriculture using at least one growth chamber illuminated by laser light. In an example embodiment of the agriculture system, a growth chamber is provided having one or more walls defining an interior portion of the growth chamber. The agriculture system may include a removable tray disposed within the interior portion of the growth chamber. The agriculture system also includes a light source, which may be disposed outside the growth chamber. The one or more walls may include at least one aperture. The light source is configured to illuminate at least a part of the interior portion of the growth chamber. In embodiments in which the light source is disposed outside the growth chamber, the light source is configured to transmit the laser light to the interior portion of the growth chamber via the at least one aperture.

Laser-based agriculture system

KAUST Repository

Ooi, Boon S.; Wong, Aloysius Tze; Ng, Tien Khee

2016-01-01

A system and method are provided for indoor agriculture using at least one growth chamber illuminated by laser light. In an example embodiment of the agriculture system, a growth chamber is provided having one or more walls defining an interior portion of the growth chamber. The agriculture system may include a removable tray disposed within the interior portion of the growth chamber. The agriculture system also includes a light source, which may be disposed outside the growth chamber. The one or more walls may include at least one aperture. The light source is configured to illuminate at least a part of the interior portion of the growth chamber. In embodiments in which the light source is disposed outside the growth chamber, the light source is configured to transmit the laser light to the interior portion of the growth chamber via the at least one aperture.

New Novae snack point

CERN Document Server

2012-01-01

Located next to the car park by the flag poles, a few metres from the Main CERN Reception (building 33), a new snack point catered by Novae will open to the public on Wednesday 8 August. More information will be available in the next issue of the Bulletin!

Line Evolution of the Nova V5587 Sgr from Early to Nebula Phase

Directory of Open Access Journals (Sweden)

T. Kajikawa

2015-02-01

Full Text Available The spectral evolution of the nova V5587 Sgr has been monitored at Koyama Astronomical Observatory and Higashi-Hiroshima Observatory, Japan, from the early to nebula phase. The nova rebrightened several times. The spectra during the early phase showed emission lines of H α, H β, O I, He I, He II, N II, Fe II. Nova V5587 Sgr is classified into the Fe II type. The helium abundance of the nova is estimated as N(He/N(H = 0.134 ± 0.09. The light curve, the spectral evolution, and the helium abundance in V5587 Sgr are similar to those of the nova PW Vul.

Effects of two desensitizing dentifrices on dentinal tubule occlusion with citric acid challenge: Confocal laser scanning microscopy study

Directory of Open Access Journals (Sweden)

Sneha Anil Rajguru

2017-01-01

Full Text Available Background: Dentin hypersensitivity results when patent tubules are exposed to pain-inducing external stimuli. Aim: This study aims to compare the effects of two desensitizing dentifrices containing NovaMin and arginine on dentinal tubule occlusion with and without citric acid challenge in vitro using confocal laser scanning microscopy (CLSM. Materials and Methods: Forty dentin discs were randomly divided into Groups I and II containing twenty specimens each, treated with NovaMin and arginine-containing dentifrices, respectively. Groups I and II were divided into subgroups A and B where IA and IIA underwent CLSM analysis to determine the percentage of tubule occlusion while IB and IIB underwent 0.3% citric acid challenge and CLSM analysis. A novel grading system was devised to categorize tubule occlusion. Results: In Group II, the percentage of occluded tubules was highest for IIA (72.25% ± 10.57% and least for IIB (42.55% ± 8.65% having statistical significance (P < 0.0005. In Group I, the difference between IA (49.9% ± 12.96% and IB (43.15% ± 12.43% was statistically insignificant (P = 0.249. On the comparison between IB and IIB statistically indifferent result was obtained (P = 0.901, whereas the difference between IA and IIA was statistically significant (P < 0.001. The results of grading system were for IA 50% of samples belonged to Grade 2, for IIA 60% - Grade 3, and for IB 70% and for IIB 90% - Grade 2. Conclusion: Dentinal tubule occlusion with arginine-containing dentifrice was significantly higher than NovaMin. However, it could not resist citric acid challenge as effectively as NovaMin. The effects of NovaMin were more sustainable as compared to arginine-containing dentifrice, thus proving to be a better desensitizing agent.

PHASE NOISE COMPARISON OF SHORT PULSE LASER SYSTEMS

Energy Technology Data Exchange (ETDEWEB)

Shukui Zhang; Stephen Benson; John Hansknecht; David Hardy; George Neil; Michelle D. Shinn

2006-08-27

This paper describes phase noise measurements of several different laser systems that have completely different gain media and configurations including a multi-kW free-electron laser. We will focus on state-of-the-art short pulse lasers, especially drive lasers for photocathode injectors. Phase noise comparison of the FEL drive laser, electron beam and FEL laser output also will be presented.

Infant mortality testing of high energy-density capacitors used on Nova

International Nuclear Information System (INIS)

Merritt, B.T.; Whitham, K.

1983-01-01

Nova is a solid state large laser for inertial confinement fusion research. Its flashlamps are driven by a 60 MJ capacitor bank. Part of this bank is being built with high energy-density capacitors, 52 μF, 22 KV, 12.5 KJ. A total of 2,645 of these capacitors have been purchased from two manufacturers. Each capacitor was infant mortality tested. The first test consisted of a high-potential test, bushing-to-case, since these capacitors have dual bushings. Then the capacitors were discharged 500 times with circuit conditions approximating the capacitors normal flashlamp load. Failure of either of these tests or if the capacitor was leaking was cause for rejection. The test results were remarkably good. Less than 0.5 percent failed the pulse-discharge test and less than 2.5 percent were rejected overall

Multicolour photometry and spectroscopy of the slow nova V475 Sct (Nova Scuti 2003)

Czech Academy of Sciences Publication Activity Database

Chochol, D.; Katysheva, N.A.; Pribulla, T.; Schmidtobreick, L.; Shugarov, S.Yu.; Škoda, Petr; Šlechta, Miroslav; Vittone, A.A.; Volkov, I. M.

2006-01-01

Roč. 6, č. 1 (2006), s. 137-142 ISSN 1009-9271 Institutional research plan: CEZ:AV0Z10030501 Keywords : cataclysmic variables * circumstellar matter * stars: novae Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 0.746, year: 2006

Photometric and spectroscopic variability of the slow nova V475 Sct (Nova Scuti 2003)

Czech Academy of Sciences Publication Activity Database

Chochol, D.; Katysheva, N.A.; Pribulla, T.; Schmidtobreick, L.; Shugarov, S.Yu.; Škoda, Petr; Šlechta, Miroslav; Vittone, A.A.; Volkov, I. M.

2005-01-01

Roč. 35, č. 2 (2005), s. 107-129 ISSN 1335-1842 R&D Projects: GA AV ČR KSK2043105 Institutional research plan: CEZ:AV0Z1003909 Keywords : novae * photometry * spectroscopy Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

High power laser downhole cutting tools and systems

Science.gov (United States)

Zediker, Mark S; Rinzler, Charles C; Faircloth, Brian O; Koblick, Yeshaya; Moxley, Joel F

2015-01-20

Downhole cutting systems, devices and methods for utilizing 10 kW or more laser energy transmitted deep into the earth with the suppression of associated nonlinear phenomena. Systems and devices for the laser cutting operations within a borehole in the earth. These systems and devices can deliver high power laser energy down a deep borehole, while maintaining the high power to perform cutting operations in such boreholes deep within the earth.

On the 2011 Outburst of the Recurrent Nova T Pyxidis

Directory of Open Access Journals (Sweden)

L. Izzo

2015-02-01

Full Text Available We discuss the nebular phase emission during the 2011 outburst of the recurrent nova T Pyxidis and present preliminaryresults on the analysis of the line profiles. We also present some discussions about the binary system configurations and the X-ray emission, showing that the white dwarf mass should be larger than 0.8 MΘ.

The progenitor of Nova Cygni 2006 (=V2362 Cyg)

NARCIS (Netherlands)

Steeghs, D.; Greimel, R.; Drew, J.; Irwin, M.; Gaensicke, B.; Groot, P.J.; Knigge, C.

2006-01-01

We report on the detection of the likely progenitor to Nova Cygni 2006 = V2362 Cyg (IAUC #8697, #8698, ATel #792) using images from the INT Photometric H-Alpha Survey (IPHAS; http://www.iphas.org). The field containing the classical nova was observed as part of our galactic plane survey on Aug. 3rd

Lasers in tattoo and pigmentation control: role of the PicoSure® laser system

Science.gov (United States)

Torbeck, Richard; Bankowski, Richard; Henize, Sarah; Saedi, Nazanin

2016-01-01

Background and objectives The use of picosecond lasers to remove tattoos has greatly improved due to the long-standing outcomes of nanosecond lasers, both clinically and histologically. The first aesthetic picosecond laser available for this use was the PicoSure® laser system (755/532 nm). Now that a vast amount of research on its use has been conducted, we performed a comprehensive review of the literature to validate the continued application of the PicoSure® laser system for tattoo removal. Study design and methods A PubMed search was conducted using the term “picosecond” combined with “laser”, “dermatology”, and “laser tattoo removal”. Results A total of 13 articles were identified, and ten of these met the inclusion criteria for this review. The majority of studies showed that picosecond lasers are an effective and safe treatment mode for the removal of tattoo pigments. Several studies also indicated potential novel applications of picosecond lasers in the removal of various tattoo pigments (eg, black, red, and yellow). Adverse effects were generally mild, such as transient hypopigmentation or blister formation, and were rarely more serious, such as scarring and/or textural change. Conclusion Advancements in laser technologies and their application in cutaneous medicine have revolutionized the field of laser surgery. Computational modeling provides evidence that the optimal pulse durations for tattoo ink removal are in the picosecond domain. It is recommended that the PicoSure® laser system continue to be used for safe and effective tattoo removal, including for red and yellow pigments. PMID:27194919

Non-contact finger vein acquisition system using NIR laser

Science.gov (United States)

Kim, Jiman; Kong, Hyoun-Joong; Park, Sangyun; Noh, SeungWoo; Lee, Seung-Rae; Kim, Taejeong; Kim, Hee Chan

2009-02-01

Authentication using finger vein pattern has substantial advantage than other biometrics. Because human vein patterns are hidden inside the skin and tissue, it is hard to forge vein structure. But conventional system using NIR LED array has two drawbacks. First, direct contact with LED array raise sanitary problem. Second, because of discreteness of LEDs, non-uniform illumination exists. We propose non-contact finger vein acquisition system using NIR laser and Laser line generator lens. Laser line generator lens makes evenly distributed line laser from focused laser light. Line laser is aimed on the finger longitudinally. NIR camera was used for image acquisition. 200 index finger vein images from 20 candidates are collected. Same finger vein pattern extraction algorithm was used to evaluate two sets of images. Acquired images from proposed non-contact system do not show any non-uniform illumination in contrary with conventional system. Also results of matching are comparable to conventional system. We developed Non-contact finger vein acquisition system. It can prevent potential cross contamination of skin diseases. Also the system can produce uniformly illuminated images unlike conventional system. With the benefit of non-contact, proposed system shows almost equivalent performance compared with conventional system.

Demonstration of Laser Cutting System for Tube Specimen

Energy Technology Data Exchange (ETDEWEB)

Jin, Y. G.; Kim, G. S.; Heo, G. S.; Baik, S. J.; Kim, H. M.; Ahn, S. B. [KAERI, Daejeon (Korea, Republic of)

2016-05-15

The oxide layer removal system was also developed because the oxide layer on the surface of the irradiated fuel cladding and components interrupted the applying the electric current during the processing. However, it was found that the mechanical testing data of the irradiated specimens with removal of oxide layer was less reliable than the specimens with oxide layer . The laser cutting system using Nd:YAG with fiber optic beam delivery has great potential in material processing applications of the irradiated fuel cladding and components due to non-contact process. Thus, the oxide layer doesn't interrupt the fabrication process during the laser cutting system. In the present study, the laser cutting system was designed to fabricate the mechanical testing specimens from the unirradiated fuel cladding with and without oxide. The feasibility of the laser cutting system was demonstrated for the fabrication of various types of unirradiated specimens. The effect of surface oxide layer was also investigated for machining process of the zirlo fuel cladding and it was found that laser beam machining could be a useful tool to fabricate the specimens with surface oxide layer. Based on the feasibility studies and demonstration, the design of the laser cutting machine for fully or partially automatic and remotely operable system will be proposed and made.

Cross Check of NOvA Oscillation Probabilities

Energy Technology Data Exchange (ETDEWEB)

Parke, Stephen J. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States). Dept. of Theoretical Physics; Messier, Mark D. [Indiana Univ., Bloomington, IN (United States). Dept. of Physics

2018-01-12

In this note we perform a cross check of the programs used by NOvA to calculate the 3-flavor oscillation probabilities with a independent program using a different method. The comparison is performed at 6 significant figures and the agreement, $|\\Delta P|/P$ is better than $10^{-5}$, as good as can be expected with 6 significant figures. In addition, a simple and accurate alternative method to calculate the oscillation probabilities is outlined and compared in the L/E range and matter density relevant for the NOvA experiment.

Lasers in tattoo and pigmentation control: role of the PicoSure® laser system

Directory of Open Access Journals (Sweden)

Torbeck R

2016-05-01

Full Text Available Richard Torbeck,1 Richard Bankowski,2 Sarah Henize,3 Nazanin Saedi,11Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 2Cynosure, Inc, Westford, MA, 3Huron Consulting Group, Chicago, IL, USABackground and objectives: The use of picosecond lasers to remove tattoos has greatly improved due to the long-standing outcomes of nanosecond lasers, both clinically and histologically. The first aesthetic picosecond laser available for this use was the PicoSure® laser system (755/532 nm. Now that a vast amount of research on its use has been conducted, we performed a comprehensive review of the literature to validate the continued application of the PicoSure® laser system for tattoo removal.Study design and methods: A PubMed search was conducted using the term "picosecond" combined with "laser", "dermatology", and "laser tattoo removal".Results: A total of 13 articles were identified, and ten of these met the inclusion criteria for this review. The majority of studies showed that picosecond lasers are an effective and safe treatment mode for the removal of tattoo pigments. Several studies also indicated potential novel applications of picosecond lasers in the removal of various tattoo pigments (eg, black, red, and yellow. Adverse effects were generally mild, such as transient hypopigmentation or blister formation, and were rarely more serious, such as scarring and/or textural change.Conclusion: Advancements in laser technologies and their application in cutaneous medicine have revolutionized the field of laser surgery. Computational modeling provides evidence that the optimal pulse durations for tattoo ink removal are in the picosecond domain. It is recommended that the PicoSure® laser system continue to be used for safe and effective tattoo removal, including for red and yellow pigments.Keywords: tattoo, removal, laser, picosecond 

Laser fusion systems for industrial process heat. Third semiannual report

International Nuclear Information System (INIS)

Bates, F.J.; Denning, R.S.; Dykhuizen, R.C.; Goldthwaite, W.H.; Kok, K.D.; Skelton, J.C.

1979-01-01

This report concentrates not only on the design of the laser fusion system but also on the cost of this system and the costs of alternative sources of energy that are expected to be in competition with the laser fusion system. The absolute values of the cost of the laser fusion system are limited by the estimates of the cost of the components and subsystems making up the laser fusion energy station. The method used in calculating costs of the laser fusion and alternative systems are laid out in detail

Evaluation of petroleum products pricing regulation in Nova Scotia : a 2 year review

International Nuclear Information System (INIS)

2008-11-01

Gasoline price regulation was introduced in Nova Scotia on July 1st, 2006. This report presented the findings and recommendations of a review of the first two years of the gasoline price regulation in Nova Scotia. The regulations had three main objectives. This review examined whether, and to what extent, they were achieved. The objectives were to stabilize price, maintain industry infrastructure, and minimize cost to consumers. The report described the rationale for the regulation, study objectives, and approach taken to gasoline regulation in Nova Scotia, including the objectives and technical aspects of how regulation works. The gasoline market in Nova Scotia was examined, including the market structure and competitive behaviour in an unregulated market. The report also provided some theoretical perspectives on how regulation was likely to affect industry structure and competitive behaviour. The extent to which the regulation was meeting its objectives was then assessed and perspectives on the regulation from consumers, retailers and wholesalers were offered. Last, the report provided a review of the findings in terms of the key elements of regulatory design and set out recommendations for improving the system. It was recommended that in order to improve certainty, particularly given the regulated price differences amongst grades, the regulations should be amended to include grade specifications referencing octane ratings. tabs., figs

Laser driven hydrodynamic instability experiments

International Nuclear Information System (INIS)

Remington, B.A.; Weber, S.V.; Haan, S.W.; Kilkenny, J.D.; Glendinning, S.G.; Wallace, R.J.; Goldstein, W.H.; Wilson, B.G.; Nash, J.K.

1992-01-01

We have conducted an extensive series of experiments on the Nova laser to measure hydrodynamic instabilities in planar foils accelerated by x-ray ablation. Single mode experiments allow a measurement of the fundamental growth rates from the linear well into the nonlinear regime; multimode foils allow an assessment of the degree of mode coupling; and surface-finish experiments allow a measurement of the evolution of a broad spectrum of random initial modes. Experimental results and comparisons with theory and simulations are presented

Laser surveillance system (LASSY)

International Nuclear Information System (INIS)

Boeck, H.; Hammer, J.

1988-01-01

The development progress during the reporting period 1988 of the laser surveillance system of spent fuel pools is summarized. The present engineered system comes close to a final version for field application as all technical questions have been solved in 1988. 14 figs., 1 tab. (Author)

Tracking Detector Performance and Data Quality in the NOvA Experiment

Energy Technology Data Exchange (ETDEWEB)

Behera, Biswaranjan [Fermilab

2017-10-10

NOvA is a long-baseline neutrino oscillation experiment. It uses the NuMI beam from Fermilab and two sampling calorimeter detectors located off-axis from the beam. The NOvA experiment measures the rate of electron-neutrino appearance in the almost pure muon-neutrino NuMI beam, with the data measured at the Near Detector being used to accurately determine the expected rate at the Far Detector. It is very important to have automated and accurate monitoring of the data recorded by the detectors so any hardware, DAQ or beam issues arising in the 344k (20k) channels of the Far (Near) detector which could affect the quality of the data taking are determined. This paper will cover the techniques and detector monitoring systems in various stages of data taking.

A indústria de calçados de Nova Serrana (MG

Directory of Open Access Journals (Sweden)

Wilson Suzigan

2005-12-01

Full Text Available On the basis of previous statistical work with data and information from RAIS - Relação Anual de Informações Sociais, characterizing the Nova Serrana shoe industry as a local production system, and the results of a field research work with visits and interviews in local firms and institutions, this paper studies the Nova Serrana local production system as a whole as well as its firms and supporting institutions. The objective is to bring empirical evidence to guide public policy and private actions with a view to upgrade the local system in two spheres: (1 productive and technological, and (2 institutional and organizational. With this purpose in mind, this paper first characterizes and describes the local system in terms of location, adjoining influenced areas, logistics, population and number of jobs, history and evolution, production structure, supporting institutions, and social, cultural and political contexts. Next, the paper characterizes local firms in terms of size, product development, trading system, cooperation between rival firms, interactions with suppliers, sources of information for product development and on market trends and production technologies, practices and policies with regard to quality, financing, and other aspects. Finally, the paper summarizes the most relevant issues for policy measures and private actions by local firms and institutions.

Exquisite Nova Light Curves from the Solar Mass Ejection Imager (SMEI)

OpenAIRE

Hounsell, R.; Bode, M. F.; Hick, P. P.; Buffington, A.; Jackson, B. V.; Clover, J. M.; Shafter, A. W.; Darnley, M. J.; Mawson, N. R.; Steele, I. A.; Evans, A.; Eyres, S. P. S.; O'Brien, T. J.

2010-01-01

We present light curves of three classical novae (KT Eridani, V598 Puppis, V1280 Scorpii) and one recurrent nova (RS Ophiuchi) derived from data obtained by the Solar Mass Ejection Imager (SMEI) on board the Coriolis satellite. SMEI provides near complete sky-map coverage with precision visible-light photometry at 102-minute cadence. The light curves derived from these sky maps offer unprecedented temporal resolution around, and especially before, maximum light, a phase of the nova eruption n...

Tourism Development Plan for Nova Lima, MG/BR: A Case Study

Directory of Open Access Journals (Sweden)

Porto Aluisio Finazzi

2014-01-01

Full Text Available The project called “Tourism Development Plan of Nova Lima, MG” was a labor required by the city of Nova Lima, through the Secretary of Municipal Tourism. The municipality of Nova Lima has numerous tourist attractions or potential for them attractive, and is developing a work of public policies aimed at structuring this activity. The objective of this project was to offer to its population, as well as the government and the private sector, the assurance of quality activity according to the international, national and state the assumptions referred to in the Municipal Tourism Plan. All work was developed by Scientific and Technical Research Data Collection, which took into consideration the participation of local stakeholders in the development of tourism through public hearings with the Section for Local Tourism, making use of Information from the Current Municipal Development Plan for Nova Lima and its Secretary of Tourism. We also note that the study was conducted in accordance with the guidelines and considerations of the Municipal Tourism Council (COMTUR of Nova Lima.

Spectroscopic observations of Nova Cygni 1975: The coronal line region revisited

International Nuclear Information System (INIS)

Ferland, G.J.; Lambert, D.L.; Woodman, J.H.

1986-01-01

A synopsis of the McDonald Observatory spectrophotometric observations of Nova Cyg 1975 (V1500 Cyg) is presented. We present these data in a form in which they can be readily accessed in the future, and also study the continous spectrum during the early nebular phase. We show that (1) the remnant probably maintained a luminosity at or above the Eddington limit for at least a year after outburst, (2) free-free emission from the coronal line region made a significant contribution to the optical continuum, and (3) the coronal line region was probably a significant source of ionizing radiation. The energetics of this nova appear to be dominated by the lift-off energy from the white dwarf and radiation from the coronal line region. Thus the light curve of Nova Cyg may tell more about the cooling of the coronal line region than about the decline of the central object. In appendices we discuss the argon abundance of Nova Cyg (less than 8 times solar) and describe how to obtain copies of the McDonald nova data

Performance of a high repetition pulse rate laser system for in-gas-jet laser ionization studies with the Leuven laser ion source LISOL

International Nuclear Information System (INIS)

Ferrer, R.; Sonnenschein, V.T.; Bastin, B.; Franchoo, S.; Huyse, M.; Kudryavtsev, Yu.; Kron, T.; Lecesne, N.; Moore, I.D.; Osmond, B.; Pauwels, D.; Radulov, D.; Raeder, S.; Rens, L.

2012-01-01

The laser ionization efficiency of the Leuven gas cell-based laser ion source was investigated under on- and off-line conditions using two distinctly different laser setups: a low-repetition rate dye laser system and a high-repetition rate Ti:sapphire laser system. A systematic study of the ion signal dependence on repetition rate and laser pulse energy was performed in off-line tests using stable cobalt and copper isotopes. These studies also included in-gas-jet laser spectroscopy measurements on the hyperfine structure of 63 Cu. A final run under on-line conditions in which the radioactive isotope 59 Cu (T 1/2 = 81.5 s) was produced, showed a comparable yield of the two laser systems for in-gas-cell ionization. However, a significantly improved time overlap by using the high-repetition rate laser system for in-gas-jet ionization was demonstrated by an increase of the overall duty cycle, and at the same time, pointed to the need for a better shaped atomic jet to reach higher ionization efficiencies.

UBVJHKLM Photometry and Low-Resolution Spectroscopy of Nova Delphini 2013 (V339 Del

Directory of Open Access Journals (Sweden)

Burlak M. A.

2015-03-01

Full Text Available We present UBVJHKLM photometric observations of Nova Delphini 2013 that started several hours before maximum light and lasted for 130 nights. Using the obtained data, we derived several photometric parameters of the Nova: the time of maximum light, brightness at maximum, rate of decline, t2 = 11 d. This places Nova Del 2013 among fast novae according to the classification introduced by Payne-Gaposchkin. We estimated the interstellar reddening EB−V = 0.18 using maps of Galactic extinction and the absolute brightness in maximum light via the MMRD relation that allowed us to determine the distance D ≈ 2.7 kpc and height above the Galactic plane z ≈ 440 pc. Low-resolution spectroscopy shows that Nova Del 2013 belongs to the Fe II spectral type of novae. The broad emission feature near 6825 Å observed during 2013 August and September may be the Raman-scattered OVI 1032 Å line.

Development of a Laser Induced Fluorescence (LIF) System with a Tunable Diode Laser

International Nuclear Information System (INIS)

Woo, Hyun Jong; Do, Jeong Jun; You, Hyun Jong; Choi, Geun Sik; Lee, Myoung Jae; Chung, Kyu Sun

2005-01-01

The Laser Induced Fluorescence (LIF) is known as one of the most powerful techniques for measurements of ion velocity distribution function (IVDF) and ion temperature by means of Doppler broadening and Doppler shift. The dye lasers are generally used for LIF system with 611.66 nm (in vac.) for Ar ion, the low power diode laser was also proposed by Severn et al with the wavelength of 664.55 nm and 668.61 nm (in vac.) for Ar ion. Although the diode laser has the disadvantages of low power and small tuning range, it can be used for LIF system at the low temperature plasmas. A tunable diode laser with 668.614 nm of center wavelength and 10 GHz mode hop free tuning region has been used for our LIF system and it can be measured the ion temperature is up to 1 eV. The ion temperature and velocity distribution function have been measured with LaB6 plasma source, which is about 0.23 eV with Ar gas and 2.2 mTorr working pressure

Cost effectiveness of endometrial ablation with the NovaSure® system versus other global ablation modalities and hysterectomy for treatment of abnormal uterine bleeding: US commercial and Medicaid payer perspectives

Directory of Open Access Journals (Sweden)

Miller JD

2015-01-01

Full Text Available Jeffrey D Miller,1 Gregory M Lenhart,1 Machaon M Bonafede,1 Cindy M Basinski,2 Andrea S Lukes,3 Kathleen A Troeger4 1Truven Health Analytics, Cambridge, MA, 2Basinski, LLC, Newburgh, IN, 3Carolina Women’s Research and Wellness Center, Durham, NC, 4Hologic, Inc, Marlborough, MA, USA Objectives: Abnormal uterine bleeding (AUB interferes with physical, emotional, and social well-being, impacting the quality of life of more than 10 million women in the USA. Hysterectomy, the most common surgical treatment of AUB, has significant morbidity, low mortality, long recovery, and high associated health care costs. Global endometrial ablation (GEA provides a surgical alternative with reduced morbidity, cost, and recovery time. The NovaSure® system utilizes unique radiofrequency impedance-based GEA technology. This study evaluated cost effectiveness of AUB treatment with NovaSure ablation versus other GEA modalities and versus hysterectomy from the US commercial and Medicaid payer perspectives. Methods: A health state transition (semi-Markov model was developed using epidemiologic, clinical, and economic data from commercial and Medicaid claims database analyses, supplemented by published literature. Three hypothetical cohorts of women receiving AUB interventions were simulated over 1-, 3-, and 5-year horizons to evaluate clinical and economic outcomes for NovaSure, other GEA modalities, and hysterectomy. Results: Model analyses show lower costs for NovaSure-treated patients than for those treated with other GEA modalities or hysterectomy over all time frames under commercial payer and Medicaid perspectives. By Year 3, cost savings versus other GEA were $930 (commercial and $3,000 (Medicaid; cost savings versus hysterectomy were $6,500 (commercial and $8,900 (Medicaid. Coinciding with a 43%–71% reduction in need for re-ablation, there were 69%–88% fewer intervention/reintervention complications for NovaSure-treated patients versus other GEA modalities

Comparison of three different laser systems for application in dentistry

Science.gov (United States)

Mindermann, Anja; Niemz, M. H.; Eisenmann, L.; Loesel, Frieder H.; Bille, Josef F.

1993-12-01

Three different laser systems have been investigated according to their possible application in dentistry: a free running and a Q-switched microsecond Ho:YAG laser, a free running microsecond Er:YAG laser and picosecond Nd:YLF laser system consisting of an actively mode locked oscillator and a regenerative amplifier. The experiments focused on the question if lasers can support or maybe replace ordinary drilling machines. For this purpose several cavities were generated with the lasers mentioned above. Their depth and quality were judged by light and electron microscopy. The results of the experiments showed that the picosecond Nd:YLF laser system has advantages compared to other lasers regarding their application in dentistry.

Nova Scotia Resources Limited annual report, 1992

International Nuclear Information System (INIS)

1992-01-01

Nova Scotia Resources was established in 1981 by the provincial government to invest in and manage Nova Scotia's participation in petroleum, energy, and mineral development. The company and its subsidiaries hold interests in oil and gas discovery areas and producing fields in the Nova Scotia offshore, and owns producing oil and gas interests in western Canada. In June 1992, oil production began from the Cohasset project, representing Canada's first commercial offshore oil production. Nearly 4 million bbl of crude will be sold in the first production season. Work is continuing on additional producing wells; the production life of the Cohasset project is currently estimated at 6 y. Offshore exploration activity is also continuing under four exploration licenses. For the 12 months ending March 31, 1992, net earnings from western oil and gas production were $369,000. Total gross revenues from oil and gas producing properties for the year were ca $4.8 million. Other 1992 activities include active exploration for salt and potash sites with potential for underground storage of natural gas. Financial statements are included. 14 figs., 2 tabs

A 1J LD pumped Nd:YAG pulsed laser system

Science.gov (United States)

Yi, Xue-bin; Wang, Bin; Yang, Feng; Li, Jing; Liu, Ya-Ping; Li, Hui-Jun; Wang, Yu; Chen, Ren

2017-11-01

A 1J LD pumped Nd;YAG pulsed laser was designed. The laser uses an oscillation and two-staged amplification structure, and applies diode bar integrated array as side-pump. The TEC temperature control device combing liquid cooling system is organized to control the temperature of the laser system. This study also analyzed the theoretical threshold of working material, the effect of thermal lens and the basic principle of laser amplification. The results showed that the laser system can achieve 1J, 25Hz pulse laser output, and the laser pulse can be output at two width: 6-7ns and 10ns, respectively, and the original beam angle is 1.2mrad. The laser system is characterized by small size, light weight, as well as good stability, which make it being applied in varied fields such as photovoltaic radar platform and etc

MAPEAMENTO DAS ÁREAS SUSCETÍVEIS À EROSÃO HÍDRICA NOS MUNICÍPIOS DE CALDAS NOVAS, NOVA AMÉRICA E RIO QUENTE (GO MAPPING THE EROSION SUSCEPTIBLE AREAS OF CALDAS NOVAS, NOVA AMÉRICA AND RIO QUENTE, GOIÁS - BRASIL

Directory of Open Access Journals (Sweden)

Luiz Fernando Coutinho de Oliveira

2007-09-01

Full Text Available

A importância de mapear as áreas suscetíveis à erosão hídrica nos municípios de Caldas Novas, Nova América e Rio Quente deve-se ao fato de que eles apresentaram os maiores índices de precipitação pluviométrica e pelo potencial que os mesmos representam para o estado de Goiás, principalmente o turístico. Na elaboração desses mapas, estabeleceram-se preliminarmente os planos de informação referentes às classes de solo, à declividade e ao uso do solo através de digitalização, empregando o software SGI/INPE, e a espacialização da intensidade de precipitação com duração de 30 minutos sobre a base cartográfica dos municípios, obtendo assim os mapas temáticos. Através do cruzamento dos mapas temáticos, foram classificadas e mapeadas as áreas suscetíveis à erosão hídrica. A metodologia empregada mostrou-se satisfatória, permitindo gerar os mapas temáticos das áreas suscetíveis à erosão hídrica nos municípios estudados que servirão de orientação para os trabalhos de campo.

PALAVRAS-CHAVE: Erosão; sistema de informação geográfica; conservação do solo.

The importance of mapping the erosion susceptible areas of Caldas Novas, Nova América and Rio Quente is that these municipalities present high rainfall rates and the potential they represent for the Goiás state, mostly for tourism. As a preliminary to elaborate these maps the soil type, slope and use of classes information were planned through digitalization using the SGI/INPE software, and a spatialization of the 30 minutes rainfall intensity over the municipalities cartographic base, obtaining the thematic maps. Through thematic maps crossing, the erosion susceptible areas were classified and mapped. The methodology used was considered satisfactory and generated the thematic

Modeling the classical nova outburst. I. Exploring the physics of a new mechanism

International Nuclear Information System (INIS)

Kutter, G.S.; Sparks, W.M.

1989-01-01

Model calculations were performed to describe a mechanism that produces classical nova outbursts on white dwarfs of 1 solar mass or less and for accretion rates of 4 x 10 to the -10th solar mass/yr or greater, i.e., the parameters corresponding to observed data of nova systems. Calculations point to four factors that can induce nuclear runaways of sufficient strength to eject about 0.0001 solar mass at speeds of several hundred to a few thousand km per second, as is observed in classical novae. These are (1) the effects of storage of angular momentum in the star's envelope during the accretion phase; (2) the reduction of centrifugal forces in the star's outer layers during the early nuclear runaway phase, through the inward transport of angular momentum; (3) the inward movement of the zone of peak nuclear burning through the convectively induced shear instability during the runaway phase; and (4) the mixing of original CO stellar matter and H-rich matter, also through the convectively induced shear instability. 58 refs

Exquisite Nova Light Curves from the Solar Mass Ejection Imager (SMEI)

Science.gov (United States)

Hounsell, R.; Bode, M. F.; Hick, P. P.; Buffington, A.; Jackson, B. V.; Clover, J. M.; Shafter, A. W.; Darnley, M. J.; Mawson, N. R.; Steele, I. A.; Evans, A.; Eyres, S. P. S.; O'Brien, T. J.

2010-11-01

We present light curves of three classical novae (CNe; KT Eridani, V598 Puppis, V1280 Scorpii) and one recurrent nova (RS Ophiuchi) derived from data obtained by the Solar Mass Ejection Imager (SMEI) on board the Coriolis satellite. SMEI provides near complete skymap coverage with precision visible-light photometry at 102 minute cadence. The light curves derived from these skymaps offer unprecedented temporal resolution around, and especially before, maximum light, a phase of the eruption normally not covered by ground-based observations. They allow us to explore fundamental parameters of individual objects including the epoch of the initial explosion, the reality and duration of any pre-maximum halt (found in all three fast novae in our sample), the presence of secondary maxima, speed of decline of the initial light curve, plus precise timing of the onset of dust formation (in V1280 Sco) leading to estimation of the bolometric luminosity, white dwarf mass, and object distance. For KT Eri, Liverpool Telescope SkyCamT data confirm important features of the SMEI light curve and overall our results add weight to the proposed similarities of this object to recurrent rather than to CNe. In RS Oph, comparison with hard X-ray data from the 2006 outburst implies that the onset of the outburst coincides with extensive high-velocity mass loss. It is also noted that two of the four novae we have detected (V598 Pup and KT Eri) were only discovered by ground-based observers weeks or months after maximum light, yet these novae reached peak magnitudes of 3.46 and 5.42, respectively. This emphasizes the fact that many bright novae per year are still overlooked, particularly those of the very fast speed class. Coupled with its ability to observe novae in detail even when relatively close to the Sun in the sky, we estimate that as many as five novae per year may be detectable by SMEI.

First Neutrino Oscillation Results from the NOvA experiment

Energy Technology Data Exchange (ETDEWEB)

Sachdev, Kanika [Fermilab

2016-11-29

NOvA is a long-baseline neutrino oscillation experiment on the NuMI muon neutrino beam at Fermilab. It consists of two functionally identical, nearly fully-active liquid-scintillator tracking calorimeters. The Near Detector (ND) at Fermilab is used to study the neutrino beam spectrum and composition before oscillations occur. The Far Detector in northern Minnesota, 810 km away, observes the oscillated beam and is used to extract the oscillation parameters. NOvA is designed to observe oscillations in two channels: disappearance channel ( ν μ → ν μ ) and ν e appearance channel ( ν μ → ν e ). This paper reports the measurements of both these channels based on the first NOvA data taken from February 16, 2014 till May 15, 2015

Spectrophotometry of nova Cygni 1975

International Nuclear Information System (INIS)

Panek, R.J.

1977-01-01

Low-resolution spectrophotometry of nova Cygni 1975 is presented for eight nights in September 1975. Representative spectrum scans from 3600 A to 4500 A (10 A bandpass) and from 6350 A to 6750 A (20 A bandpass) also are shown

Optical and Near-infrared Study of Nova V2676 Oph 2012

Energy Technology Data Exchange (ETDEWEB)

Raj, A. [Korea Astronomy and Space Science Institute, Daejeon, 34055 (Korea, Republic of); Das, R. K. [Department of Astrophysics and Cosmology, S N Bose National Centre for Basic Sciences, Salt Lake, Kolkata 700106 (India); Walter, F. M., E-mail: ashish.raj@iiap.res.in [Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794-3800 (United States)

2017-02-01

We present optical spectrophotometric and near-infrared (NIR) photometric observations of the nova V2676 Oph covering the period from 2012 March 29 through 2015 May 8. The optical spectra and photometry of the nova have been taken from SMARTS and Asiago; the NIR photometry was obtained from SMARTS and Mt. Abu. The spectra were dominated by strong H i lines from the Balmer series, Fe ii, N i, and [O i] lines in the initial days, typical of an Fe ii type nova. The measured FWHM for the H β and H α lines was 800–1200 km s{sup −1}. There was pronounced dust formation starting 90 days after the outburst. The J − K color was the largest among recent dust-forming novae.

Evolution of shiva laser alignment systems

International Nuclear Information System (INIS)

Boyd, R.D.

1980-07-01

The Shiva oscillator pulse is preamplified and divided into twenty beams. Each beam is then amplified, spatially filtered, directed, and focused onto a target a few hundred micrometers in size producing optical intensities up to 10 16 W/cm 2 . The laser was designed and built with three automatic alignment systems: the oscillator alignment system, which aligns each of the laser's three oscillators to a reference beamline; the chain input pointing system, which points each beam into its respective chain; and the chain output pointing, focusing and centering system which points, centers and focuses the beam onto the target. Recently the alignment of the laser's one hundred twenty spatial filter pinholes was also automated. This system uses digitized video images of back-illuminated pinholes and computer analysis to determine current positions. The offset of each current position from a desired center point is then translated into stepper motor commands and the pinhole is moved the proper distance. While motors for one pinhole are moving, the system can digitize, analyze, and send commands to other motors, allowing the system to efficiently align several pinholes in parallel

Inner Disk Structure of Dwarf Novae in the Light of X-Ray Observations

Directory of Open Access Journals (Sweden)

S. Balman

2015-02-01

Full Text Available Diversity of the X-ray observations of dwarf nova are still not fully understood. I review the X-ray spectral characteristics of dwarf novae during the quiescence in general explained by cooling flow models and the outburst spectra that show hard X-ray emission dominantly with few sources that reveal soft X-ray/EUV blackbody emission. The nature of aperiodic time variability of brightness of dwarf novae shows band limited noise, which can be adequately described in the framework of the model of propagating fluctuations. The frequency of the break (1-6 mHz indicates inner disk truncation of the optically thick disk with a range of radii (3.0-10.0×109 cm. The RXTE and optical (RTT150 data of SS Cyg in outburst and quiescence reveal that the inner disk radius moves towards the white dwarf and receeds as the outburst declines to quiescence. A preliminary analysis of SU UMa indicates a similar behaviour. In addition, I find that the outburst spectra of WZ Sge shows two component spectrum of only hard X-ray emission, one of which may be fitted with a power law suggesting thermal Comptonization occuring in the system. Cross-correlations between the simultaneous UV and X-ray light curves (XMM −Newton of five DNe in quiescence show time lags in the X-rays of 96-181 sec consistent with travel time of matter from a truncated inner disk to the white dwarf surface. All this suggests that dwarf novae and other plausible nonmagnetic systems have truncated accretion disks indicating that the disks may be partially evaporated and the accretion may occur through hot (coronal flows in the disk.

5. Neuromarketing: uma nova disciplina acadêmica?

OpenAIRE

Eric David Cohen; Gabriela Guimarães Lima; Peter Alexander Bleinroth Schulz

2017-01-01

Através da aplicação de técnicas neurocientíficas, o Neuromarketing busca entender como ocorrem os processos de decisão de compra. Verifica-se que há um grande movimento em torno do Neuromarketing no ambiente empresarial, apontando que o desenvolvimento desta nova área de conhecimento, bem como a sua possível autonomia, estão em desenvolvimento. Por meio de um estudo exploratório, mapeou-se a construção deste campo de conhecimento no tempo, levando à formação de uma possível nova disciplina c...

Laser puncture therapy of nervous system disorders

Energy Technology Data Exchange (ETDEWEB)

Anishchenko, G.; Kochetkov, V.

1984-08-29

The authors discuss experience with treatment of nervous system disorders by means of laser-puncture therapy. Commenting on the background of the selection of this type of treatment, they explain that once researchers determined the biological action of laser light on specific nerve receptors of the skin, development of laser apparatus capable of concentrating the beam in the millimeter band was undertaken. The devices that are being used for laser-puncture are said to operate in the red helium-neon band of light. The authors identify beam parameters that have been selected for different groups of acupuncture points of the skin, and the courses of treatment (in seconds of radiation) and their time intervals. They go on to discuss the results of treatment of over 800 patients categorized in a group with disorders of the peripheral nervous system and a second group with disorders of the central nervous system.

Fiber laser front end for high energy petawatt laser systems

International Nuclear Information System (INIS)

Dawson, J W; Messerly, M J; Phan, H; Mitchell, S; Drobshoff, A; Beach, R J; Siders, C; Lucianetti, A; Crane, J K; Barty, C J

2006-01-01

We are developing a fiber laser front end suitable for high energy petawatt laser systems on large glass lasers such as NIF. The front end includes generation of the pulses in a fiber mode-locked oscillator, amplification and pulse cleaning, stretching of the pulses to >3ns, dispersion trimming, timing, fiber transport of the pulses to the main laser bay and amplification of the pulses to an injection energy of 150 (micro)J. We will discuss current status of our work including data from packaged components. Design detail such as how the system addresses pulse contrast, dispersion trimming and pulse width adjustment and impact of B-integral on the pulse amplification will be discussed. A schematic of the fiber laser system we are constructing is shown in figure 1 below. A 40MHz packaged mode-locked fiber oscillator produces ∼1nJ pulses which are phase locked to a 10MHz reference clock. These pulses are down selected to 100kHz and then amplified while still compressed. The amplified compressed pulses are sent through a non-linear polarization rotation based pulse cleaner to remove background amplified spontaneous emission (ASE). The pulses are then stretched by a chirped fiber Bragg grating (CFBG) and then sent through a splitter. The splitter splits the signal into two beams. (From this point we follow only one beam as the other follows an identical path.) The pulses are sent through a pulse tweaker that trims dispersion imbalances between the final large optics compressor and the CFBG. The pulse tweaker also permits the dispersion of the system to be adjusted for the purpose of controlling the final pulse width. Fine scale timing between the two beam lines can also be adjusted in the tweaker. A large mode area photonic crystal single polarization fiber is used to transport the pulses from the master oscillator room to the main laser bay. The pulses are then amplified a two stage fiber amplifier to 150mJ. These pulses are then launched into the main amplifier

New studies of nuclear decay γ-rays from novae

International Nuclear Information System (INIS)

Starrfield, S.; Truran, J.W.; Wiescher, M.C.; Sparks, W.M.

1997-01-01

The cause of the nova outburst is a thermonuclear runaway (TNR) in hydrogen rich material transferred by a companion onto a white dwarf. Studies of this phenomenon have shown that the TNR produces large concentrations of the short lived positron unstable isotopes of the CNO nuclei which are transported to the surface by convection so that early in the outburst we expect significant numbers of radioactive decays to occur at the surface. The resulting γ-ray emission may be detectable from nearby novae early in their outbursts. The TNR is also expected to produce substantial amounts of 7 Be and 22 Na. Their decays also yield potentially detectable levels of γ-ray emission for relatively nearby novae. We are also interested in the role played by novae in the production of the ∼2M circle-dot of 26 Al found in the galaxy. In order to improve our predictions of this phenomenon, we have performed a new set of calculations of TNR close-quote s on ONeMg and CO white dwarfs with an updated nuclear reaction network and opacities. copyright 1997 American Institute of Physics

A novel diode laser system for photodynamic therapy

DEFF Research Database (Denmark)

Samsøe, E.; Andersen, P. E.; Petersen, P.

2001-01-01

In this paper a novel diode laser system for photodynamic therapy is demonstrated. The system is based on linear spatial filtering and optical phase conjugate feedback from a photorefractive BaTiO3 crystal. The spatial coherence properties of the diode laser are significantly improved. The system...

Development of portable laser peening systems for nuclear power reactors

International Nuclear Information System (INIS)

Chida, Itaru; Uehara, Takuya; Yoda, Masaki; Miyasaka, Hiroyuki; Kato, Hiromi

2009-01-01

Stress corrosion cracking (SCC) is the major factor to reduce the reliability of aged reactor components. Toshiba has developed various laser-based maintenance and repair technologies and applied them to existing nuclear power plants. Laser-based technology is considered to be the best tool for remote processing in nuclear power plants, and particularly so for the maintenance and repair of reactor core components. Accessibility could be drastically improved by a simple handling system owing to the absence of reactive force against laser irradiation and the flexible optical fiber. For the preventive maintenance, laser peening technology was developed and applied to reactor components in operating BWRs and PWRs. Laser peening is a novel process to improve residual stress from tensile to compressive on material surface layer by irradiating focused high-power laser pulses in water without any surface preparations. Laser peening systems, which deliver laser pulses with mirrors or through an optical fiber, were developed and have been applied to preventive maintenance against SCC in nuclear power reactors since 1999. Each system was composed of laser oscillators, a beam delivery system, a laser irradiation head, remote handling equipment and a monitor/control system. Beam delivery with mirrors was accomplished through alignment/tracking functions with sufficient accuracy. Reliable fiber-delivery was attained by the development of a novel input coupling optics and an irradiation head with auto-focusing. Recently, we have developed portable laser peening (PLP) system which could employ both mirror- and fiber- delivery technologies. Size and weight of the PLP system for BWR bottom was almost 1/25 compared to the previous system. PLP system would be the applicable to both BWRs and PWRs as one of the maintenance technologies. (author)

Experimental study of the {sup 22}Ne(p,{gamma}){sup 23}Na reaction and its implications for novae scenarios

Energy Technology Data Exchange (ETDEWEB)

Menzel, Marie-Luise

2013-08-01

The {sup 22}Ne(p,{gamma}){sup 23}Na reaction belongs to the catalytic neon-sodium cycle and has an important role in the explosive hydrogen burning. The neon-sodium cycle takes place at temperatures of T = 0.1 - 0.5 GK and is assumed to occur in different astrophysical systems: e.g. in novae, in super novae of type Ia and during the shell-burning of red giant branch stars. The implications of {sup 22}Ne(p,{gamma}){sup 23}Na and the neon-sodium cycle in a nova scenario have been studied by using the nuclear network code libnucnet at GSI in Darmstadt. A nova is an outburst of matter in a binary system consisting of a white dwarf and a red giant star. It is therefore a representative phenomenon for explosive hydrogen burning. For the calculation of the nucleosynthesis during the nova outburst, the code libnucnet requires the initial mass composition of the novae partners, the temperature and density profiles of the nova explosion and the thermonuclear reaction rates of the participating reactions. In the following, the code determined the flow and the final atomic abundance in the neon-sodium cycle during the entire nova process. Additionally, the influence of the temperature profile of the novae outburst as well as the thermonuclear reaction rate of the {sup 22}Ne(p,{gamma}){sup 23}Na reaction on the final atomic abundance in the outburst has been studied. A characteristic measure for the reactions in astrophysical environments is the thermonuclear reaction rate. The reaction rate of {sup 22}Ne(p,{gamma}){sup 23}Na has still strong uncertainties in the temperature range of T = 0.03 - 0.3 GK. These uncertainties are based on insufficient upper limits of the resonance strengths as well as the possible existence of tentative states that are populated in the energy range of E{sup lab}{sub p} = 30 - 300 keV. The research presented in this thesis is dedicated to the experimental study of the {sup 22}Ne(p,{gamma}){sup 23}Na reaction for an improved determination of the

Laser systems with diamond optical elements

International Nuclear Information System (INIS)

Seitz, J.R.

1975-01-01

High power laser systems with optical elements of diamond having a thermal conductivity of at least 10 W/cm. 0 K at 300 0 K and an optical absorption at the laser beam wavelength of no more than 10 to 20 percent are described. (U.S.)

High-power green diode laser systems for biomedical applications

DEFF Research Database (Denmark)

Müller, André

propagation parameters and therefore efficiently increases the brightness of compact and cost-effective diode laser systems. The condition of overlapping beams is an ideal scenario for subsequent frequency conversion. Based on sum-frequency generation of two beam combined diode lasers a 3.2 fold increase...... output power of frequency doubled single emitters is limited by thermal effects potentially resulting in laser degradation and failure. In this work new concepts for power scaling of visible diode laser systems are introduced that help to overcome current limitations and enhance the application potential....... Implementing the developed concept of frequency converted, beam combined diode laser systems will help to overcome the high pump thresholds for ultrabroad bandwidth titanium sapphire lasers, leading towards diode based high-resolution optical coherence tomography with enhanced image quality. In their entirety...

Infrared laser scattering system for the plasma diagnostics

International Nuclear Information System (INIS)

Hiraki, Naoji; Kawasaki, Shoji; Muraoka, Katsunori

1975-01-01

As the results of the parametric studies of the double discharge TEA CO 2 laser, the required properties on the laser system for the scattering diagnostics of plasmas are shown to be realized with our CO 2 laser. The direction of the future improvements of the laser performance is also discussed. (auth.)

Hohlraum drive and implosion experiments on Nova. Revision 1

International Nuclear Information System (INIS)

Kilkenny, J.D.; Suter, L.J.; Cable, M.D.

1994-01-01

Experiments on Nova have demonstrated hohlraum radiation temperatures up to 300 eV and in lower temperature experiments reproducible time integrated symmetry to 1--2%. Detailed 2-D LASNEX simulations satisfactorily reproduce Nova's drive and symmetry scaling data bases. Hohlraums has been used for implosion experiments achieving convergence ratios (initial capsule radius/final fuel radius) up to 24 with high density glass surrounding a hot gas fill

Infrared and optical observations of Nova Mus 1983

International Nuclear Information System (INIS)

Whitelock, P.A.; Carter, B.S.; Feast, M.W.; Glass, I.S.; Laney, D.; Menzies, J.W.

1984-01-01

Extensive optical (UBVRI) and infrared (JHKL) photometry of Nova Mus 1983 obtained over a period of 300 days is tabulated. Infrared and optical spectra are described. Although by classical definition this was a fast nova its later development was slower than for typical objects of this class. Surprisingly the development of infrared thermal dust emission did not occur. Throughout the period covered, the infrared emission was characteristic of a bound-free plus free-free plasma continuum with emission lines. (author)

SALT high-resolution spectroscopy of nova PNV J15384000-4744500

Science.gov (United States)

Aydi, E.; Buckley, D. A. H.; Mohamed, S.; Whitelock, P. A.

2018-06-01

We report on high-resolution spectroscopy of PNV J15384000-4744500 which was reported as a possible nova by Rob Kaufman (Bright, Victoria, Australia; CBAT follow-up: http://www.cbat.eps.harvard.edu/unconf/followups/J15384000-4744500.html) and confirmed as a classical nova by F. Walter (ATel #11681).

Chaotic dynamics and chaos control in nonlinear laser systems

International Nuclear Information System (INIS)

Fang Jinqing; Yao Weiguang

2001-01-01

Chaotic dynamics and chaos control have become a great challenge in nonlinear laser systems and its advances are reviewed mainly based on the ring cavity laser systems. The principle and stability conditions for time-delay feedback control are analyzed and applied to chaos control in the laser systems. Other advanced methods of chaos control, such as weak spatial perturbation and occasional proportional feedback technique, are discussed. Prospects of chaos control for application (such as improvement of laser power and performance, synchronized chaos secure communication and information processing) are pointed out finally

Improvement of laser irradiation uniformity in GEKKO XII glass laser system

International Nuclear Information System (INIS)

Miyanaga, Noriaki; Matsuoka, Shinichi; Ando, Akinobu; Amano, Shinji; Nakatsuka, Masahiro; Kanabe, Tadashi; Jitsuno, Takahisa; Nakai, Sadao

1995-01-01

The uniform laser irradiation is one of key issues in the direct drive laser fusion research. The several key technologies for the uniform laser irradiation are reported. This paper includes the uniformity performance as a result of the introduction of the random phase plate, the partially coherent light and the beam smoothing by spectral dispersion into the New Gekko XI glass laser system. Finally the authors summarize the overall irradiation uniformity on the spherical target surface by considering the power imbalance effect. The technologies developed for the beam smoothing and the power balance control enable them to achieve the irradiation nonuniformities of around 1% level for a foot pulse and of a few % for a main drive pulse, respectively

Neutrino Oscillation Results from NOvA

CERN Multimedia

CERN. Geneva

2016-01-01

NOvA is an accelerator long-baseline neutrino oscillation experiment optimised to measure electron neutrino appearance in a high-purity beam of muon neutrinos from Fermilab. The exciting discovery of the theta13 neutrino mixing angle in 2012 has opened a door to making multiple new measurements of neutrinos. These include leptonic CP violation, the neutrino mass ordering and the octant of theta23. NOvA with its 810km baseline and higher energy beam has about triple the matter effect of T2K which opens a new window on the neutrino mass ordering. With about 20% of our design beam exposure and significant analysis improvements we have recently released updated results. I will present both our disappearance and appearance measurements.

Investigation of dye laser excitation of atomic systems

International Nuclear Information System (INIS)

Abate, J.A.

1977-01-01

A stabilized cw dye laser system and an optical pumping scheme for a sodium atomic beam were developed, and the improvements over previously existing systems are discussed. A method to stabilize both the output intensity and the frequency of the cw dye laser for periods of several hours is described. The fluctuation properties of this laser are investigated by photon counting and two-time correlation measurements. The results show significant departures from the usual single-mode laser theory in the region of threshold and below. The implications of the deviation from accepted theory are discussed. The atomic beam system that was constructed and tested is described. A method of preparing atomic sodium so that it behaves as a simple two-level atom is outlined, and the results of some experiments to study the resonant interaction between the atoms and the dye laser beam are presented

A digital intensity stabilization system for HeNe laser

Science.gov (United States)

Wei, Zhimeng; Lu, Guangfeng; Yang, Kaiyong; Long, Xingwu; Huang, Yun

2012-02-01

A digital intensity stabilization system for HeNe laser is developed. Based on a switching power IC to design laser power supply and a general purpose microcontroller to realize digital PID control, the system constructs a closed loop to stabilize the laser intensity by regulating its discharge current. The laser tube is made of glass ceramics and its integrated structure is steady enough to eliminate intensity fluctuations at high frequency and attenuates all intensity fluctuations, and this makes it easy to tune the control loop. The control loop between discharge current and photodiode voltage eliminates the long-term drifts. The intensity stability of the HeNe laser with this system is 0.014% over 12 h.

Phase Noise Comparision of Short Pulse Laser Systems

Energy Technology Data Exchange (ETDEWEB)

S. Zhang; S. V. Benson; J. Hansknecht; D. Hardy; G. Neil; Michelle D. Shinn

2006-12-01

This paper describes the phase noise measurement on several different mode-locked laser systems that have completely different gain media and configurations including a multi-kW free-electron laser. We will focus on the state of the art short pulse lasers, especially the drive lasers for photocathode injectors. A comparison between the phase noise of the drive laser pulses, electron bunches and FEL pulses will also be presented.

Excimer laser beam delivery systems for medical applications

Science.gov (United States)

Kubo, Uichi; Hashishin, Yuichi; Okada, Kazuyuki; Tanaka, Hiroyuki

1993-05-01

We have been doing the basic experiments of UV laser beams and biotissue interaction with both KrF and XeCl lasers. However, the conventional optical fiber can not be available for power UV beams. So we have been investigating about UV power beam delivery systems. These experiments carry on with the same elements doped quartz fibers and the hollow tube. The doped elements are OH ion, chlorine and fluorine. In our latest work, we have tried ArF excimer laser and biotissue interactions, and the beam delivery experiments. From our experimental results, we found that the ArF laser beam has high incision ability for hard biotissue. For example, in the case of the cow's bone incision, the incision depth by ArF laser was ca.15 times of KrF laser. Therefore, ArF laser would be expected to harden biotissue therapy as non-thermal method. However, its beam delivery is difficult to work in this time. We will develop ArF laser beam delivery systems.

Wavelength stabilized multi-kW diode laser systems

Science.gov (United States)

Köhler, Bernd; Unger, Andreas; Kindervater, Tobias; Drovs, Simon; Wolf, Paul; Hubrich, Ralf; Beczkowiak, Anna; Auch, Stefan; Müntz, Holger; Biesenbach, Jens

2015-03-01

We report on wavelength stabilized high-power diode laser systems with enhanced spectral brightness by means of Volume Holographic Gratings. High-power diode laser modules typically have a relatively broad spectral width of about 3 to 6 nm. In addition the center wavelength shifts by changing the temperature and the driving current, which is obstructive for pumping applications with small absorption bandwidths. Wavelength stabilization of high-power diode laser systems is an important method to increase the efficiency of diode pumped solid-state lasers. It also enables power scaling by dense wavelength multiplexing. To ensure a wide locking range and efficient wavelength stabilization the parameters of the Volume Holographic Grating and the parameters of the diode laser bar have to be adapted carefully. Important parameters are the reflectivity of the Volume Holographic Grating, the reflectivity of the diode laser bar as well as its angular and spectral emission characteristics. In this paper we present detailed data on wavelength stabilized diode laser systems with and without fiber coupling in the spectral range from 634 nm up to 1533 nm. The maximum output power of 2.7 kW was measured for a fiber coupled system (1000 μm, NA 0.22), which was stabilized at a wavelength of 969 nm with a spectral width of only 0.6 nm (90% value). Another example is a narrow line-width diode laser stack, which was stabilized at a wavelength of 1533 nm with a spectral bandwidth below 1 nm and an output power of 835 W.

Effect of Undiagnosed Deep Adenomyosis After Failed NovaSure Endometrial Ablation

NARCIS (Netherlands)

Mengerink, B.B.; Wurff, A.A. van der; Haar, J.F. ter; Rooij, I.A.L.M. van; Pijnenborg, J.M.

2015-01-01

STUDY OBJECTIVE: To determine the prevalence of adenomyosis and deep adenomyosis after NovaSure (Hologic Inc., Newark, DE) endometrial ablation in hysterectomy specimens after NovaSure endometrial ablation failure. DESIGN: Prospective observational study (Canadian Task Force classification II-2).

Interpretation of eclipsing light curves of dwarf novae

International Nuclear Information System (INIS)

Matvienko, A.N.; Cherepashchuk, A.M.; Yagola, A.G.

1988-01-01

The method for interpretation of eclipsing light curves of dwarf novae is proposed, taking into account the influence of the hot spot situated in the outer part of the disk-like envelope surrounding a white dwarf. This method is applied to the analysis of the eclipsing light curves of the system Z Cha in the quiet and active stages. It is shown that the optical luminosity of the hot spot in the system Z Cha in the active stage is 3-5 times greater than that in the quiet stage. Radius of the disk-like envelope in the active stage is more than twice greater than that in the quiet stage

Ten-year literature review of global endometrial ablation with the NovaSure® device

Directory of Open Access Journals (Sweden)

Gimpelson RJ

2014-03-01

Full Text Available Richard J Gimpelson Mercy Clinic, Minimally Invasive Gynecology, Department of Obstetrics and Gynecology, Mercy Hospital St Louis, St Louis, MO, USA Abstract: This review examines the peer-reviewed literature describing prospective studies that report amenorrhea rates, patient satisfaction, and surgical reintervention rates following the NovaSure® endometrial ablation procedure. A search of the English-language literature published from 2000 to 2011 was conducted using PubMed. Ten prospective studies, six single-arm NovaSure trials, and four randomized controlled trials comparing the NovaSure procedure with other global endometrial ablation modalities met the inclusion criteria and were reviewed. The follow-up periods ranged from 6 to 60 months. Amenorrhea rates for the NovaSure procedure ranged from 30.0% to 75.0%. Patients who reported being satisfied with the NovaSure procedure ranged from 85.0% to 94.0%. In randomized controlled trials with other global endometrial ablation modalities, amenorrhea rates at 12 months with the NovaSure procedure ranged from 43.0% to 56.0%, while other modalities ranged from 8% to 24%. In addition, this manuscript reviews the following: the NovaSure technology; use of the NovaSure procedure in the office setting; intraoperative and postoperative pain; effects on premenstrual syndrome (PMS; dysmenorrhea; special circumstances, including presence of uterine disease, history of cesarean delivery, coagulopathy, or use of anticoagulant medication; post-procedure uterine cavity assessment and cancer risk; contraception and pregnancy; and safety. Keywords: abnormal uterine bleeding, menorrhagia, endometrial ablation, NovaSure®