WorldWideScience

Sample records for binary system hd

  1. Dynamical Study of the Exoplanet Host Binary System HD 106515

    Science.gov (United States)

    Rica, F. M.; Barrena, R.; Henríquez, J. A.; Pérez, F. M.; Vargas, P.

    2017-01-01

    HD 106515 AB (STF1619 AB) is a high common proper motion and common radial velocity binary star system composed of two G-type bright stars located at 35 pc and separated by about 7 arcsec. This system was observed by the Hipparcos satellite with a precision in distance and proper motion of 3 and 2%, respectively. The system includes a circumprimary planet of nearly 10 Jupiter masses and a semimajor axis of 4.59 AU, discovered using the radial velocity method. The observational arc of 21° shows a small curvature that evidences HD 106515 AB is a gravitationally bound system. This work determines the dynamical parameters for this system which reinforce the bound status of both stellar components. We determine orbital solutions from instantaneous position and velocity vectors. In addition, we provide a very preliminary orbital solution and a distribution of the orbital parameters, obtained from the line of sight (z). Our results show that HD 106515 AB presents an orbital period of about 4 800 years, a semimajor axis of 345 AU and an eccentricity of about 0.42. Finally, we use an N-body numerical code to perform simulations and reproduce the longer term octupole perturbations on the inner orbit.

  2. Differential rotation on both components of the pre main-sequence binary system HD 155555

    OpenAIRE

    Dunstone, N. J.; Hussain, G A J; Cameron, A. Collier; Marsden, S. C.; Jardine, M.; Barnes, J. R.; Vlex, J. C. Ramirez; Donati, J.-F.

    2008-01-01

    We present the first measurements of surface differential rotation on a pre-main sequence binary system. Using intensity (Stokes I) and circularly polarised (Stokes V) timeseries spectra, taken over eleven nights at the Anglo-Australian Telescope (AAT), we incorporate a solar-like differential rotation law into the surface imaging process. We find that both components of the young, 18 Myr, HD 155555 (V824 Ara, G5IV + K0IV) binary system show significant differential rotation. The equator-pole...

  3. Apsidal motion in massive close binary systems. I. HD 165052 an extreme case?

    CERN Document Server

    Ferrero, G; Benvenuto, O G; Fernández-Lajús, E

    2013-01-01

    We present a new set of radial-velocity measurements of the spectroscopic binary HD 165052 obtained by disentangling of high-resolution optical spectra. The longitude of the periastron (60 +- 2 degrees) shows a variation with respect to previous studies. We have determined the apsidal motion rate of the system (12.1 +- 0.3 degree/yr), which was used to calculate the absolute masses of the binary components: M_1 = 22.5 +- 1.0 and M_2 = 20.5 +- 0.9 solar masses. Analysing the separated spectra we have re-classified the components as O7Vz and O7.5Vz stars.

  4. Asteroseismic modelling of the Binary HD 176465

    CERN Document Server

    Nsamba, B; Campante, T L; Reese, D R; White, T R; Hernández, A García; Jiang, C

    2016-01-01

    The detection and analysis of oscillations in binary star systems is critical in understanding stellar structure and evolution. This is partly because such systems have the same initial chemical composition and age. Solar-like oscillations have been detected by Kepler in both components of the asteroseismic binary HD 176465. We present an independent modelling of each star in this binary system. Stellar models generated using MESA (Modules for Experiments in Stellar Astrophysics) were fitted to both the observed individual frequencies and complementary spectroscopic parameters. The individual theoretical oscillation frequencies for the corresponding stellar models were obtained using GYRE as the pulsation code. A Bayesian approach was applied to find the probability distribution functions of the stellar parameters using AIMS (Asteroseismic Inference on a Massive Scale) as the optimisation code. The ages of HD 176465 A and HD 176465 B were found to be 2.81 $\\pm$ 0.48 Gyr and 2.52 $\\pm$ 0.80 Gyr, respectively. ...

  5. The magnetic field of the double-lined spectroscopic binary system HD 5550

    CERN Document Server

    Alecian, E; Neiner, C; Folsom, C P; Leroy, B

    2016-01-01

    (Abridged) In the framework of the BinaMicS project, we have begun a study of the magnetic properties of a sample of intermediate-mass and massive short-period binary systems, as a function of binarity properties. We report in this paper the characterisation of the magnetic field of HD 5550, a double-lined spectroscopic binary system of intermediate-mass, using high-resolution spectropolarimetric Narval observations of HD 5550. We first fit the intensity spectra using Zeeman/ATLAS9 LTE synthetic spectra to estimate the effective temperatures, microturbulent velocities, and the abundances of some elements of both components, as well as the light-ratio of the system. We then fit the least-square deconvolved $I$ profiles to determine the radial and projected rotational velocities of both stars. We then analysed the shape and evolution of the LSD $V$ profiles using the oblique rotator model to characterise the magnetic fields of both stars. We confirm the Ap nature of the primary, previously reported in the liter...

  6. Differential rotation on both components of the pre main-sequence binary system HD 155555

    CERN Document Server

    Dunstone, N J; Cameron, A Collier; Marsden, S C; Jardine, M; Barnes, J R; Vlex, J C Ramirez; Donati, J -F

    2008-01-01

    We present the first measurements of surface differential rotation on a pre-main sequence binary system. Using intensity (Stokes I) and circularly polarised (Stokes V) timeseries spectra, taken over eleven nights at the Anglo-Australian Telescope (AAT), we incorporate a solar-like differential rotation law into the surface imaging process. We find that both components of the young, 18 Myr, HD 155555 (V824 Ara, G5IV + K0IV) binary system show significant differential rotation. The equator-pole laptimes as determined from the intensity spectra are 80 days for the primary star and 163 days for the secondary. Similarly for the magnetic spectra we obtain equator-pole laptimes of 44 and 71 days respectively, showing that the shearing timescale of magnetic regions is approximately half that found for stellar spots. Both components are therefore found to have rates of differential rotation similar to those of the same spectral type main sequence single stars. The results for HD 155555 are therefore in contrast to tho...

  7. The first magnetic maps of a pre-main sequence binary star system - HD 155555

    CERN Document Server

    Dunstone, N J; Cameron, A Collier; Marsden, S C; Jardine, M; Stempels, H C; Vlex, J C Ramirez; Donati, J -F

    2008-01-01

    We present the first maps of the surface magnetic fields of a pre-main sequence binary system. Spectropolarimetric observations of the young, 18 Myr, HD 155555 (V824 Ara, G5IV + K0IV) system were obtained at the Anglo-Australian Telescope in 2004 and 2007. Both datasets are analysed using a new binary Zeeman Doppler imaging (ZDI) code. This allows us to simultaneously model the contribution of each component to the observed circularly polarised spectra. Stellar brightness maps are also produced for HD 155555 and compared to previous Doppler images. Our radial magnetic maps reveal a complex surface magnetic topology with mixed polarities at all latitudes. We find rings of azimuthal field on both stars, most of which are found to be non-axisymmetric with the stellar rotational axis. We also examine the field strength and the relative fraction of magnetic energy stored in the radial and azimuthal field components at both epochs. A marked weakening of the field strength of the secondary star is observed between t...

  8. A radio map of the colliding winds in the very massive binary system HD 93129A

    Science.gov (United States)

    Benaglia, P.; Marcote, B.; Moldón, J.; Nelan, E.; De Becker, M.; Dougherty, S. M.; Koribalski, B. S.

    2015-07-01

    Context. Radio observations are an effective tool for discovering particle acceleration regions in colliding-wind binaries through detection of synchrotron radiation. Wind-collision region (WCR) models can reproduce the radio continuum spectra of massive binaries. However, key constraints for models come from high-resolution imaging. Only five WCRs have been resolved to date at radio frequencies on milliarcsec (mas) angular scales. The source HD 93129A, a prototype of the very few known O2 I stars, is a promising target for study. Recently, a second massive, early-type star about 50 mas away was discovered, and a non-thermal radio source was detected in the region. Preliminary long-baseline array data suggest that a significant fraction of the radio emission from the system comes from a putative WCR. Aims: We seek evidence that HD 93129A is a massive binary system with colliding stellar winds that produce non-thermal radiation through spatially resolved images of the radio emitting regions. Methods: We completed observations with the Australian Long Baseline Array (LBA) to resolve the system at mas angular resolutions and reduced archival Australia Telescope Compact Array (ATCA) data to derive the total radio emission. We also compiled optical astrometric data of the system in a homogeneous way. We reduced historical Hubble Space Telescope data and obtained absolute and relative astrometry with milliarcsec accuracy. Results: The astrometric analysis leads us to conclude that the two stars in HD 93129A form a gravitationally bound system. The LBA data reveal an extended arc-shaped non-thermal source between the two stars, which is indicative of a WCR. The wind momentum-rate ratio of the two stellar winds is estimated. The ATCA data show a point source with a change in flux level between 2003-4 and 2008-9, which is modeled with a non-thermal power-law spectrum with spectral indices of -1.03 ± 0.09 and -1.21 ± 0.03, respectively. The mass-loss rates derived from the

  9. Non-LTE analysis of subluminous O-star. V - The binary system HD 128220

    Science.gov (United States)

    Gruschinske, J.; Hamann, W. R.; Kudritzki, R. P.; Simon, K. P.; Kaufmann, J. P.

    1983-05-01

    Spectra of the binary system HD 128220 were taken in the UV and in the visual. The hot component - an O subdwarf - is analysed by means of non-LTE calculations. The cool companion has an effective temperature about 5500 ± 500K (Type G). The discussion of the stellar parameters arrives at results which agree with those derived from the mass function (Wallerstein and Wolff, 1966): if both components have about the same mass, these masses lie above 3 M_sun;. An O subdwarf of such a high mass has not yet been found and may be a supernova candidate. However, within the error margin of the orbital data also a mass ratio of MO/MG = 0.5 cannot be excluded, which would lead to stellar parameters which are more common for sdO's.

  10. The magnetic field of the double-lined spectroscopic binary system HD 5550

    Science.gov (United States)

    Alecian, E.; Tkachenko, A.; Neiner, C.; Folsom, C. P.; Leroy, B.

    2016-05-01

    Context. The origin of fossil fields in intermediate- and high-mass stars is poorly understood, as is the interplay between binarity and magnetism during stellar evolution. Thus we have begun a study of the magnetic properties of a sample of intermediate-mass and massive short-period binary systems as a function of binarity properties. Aims: This paper specifically aims to characterise the magnetic field of HD 5550, a double-lined spectroscopic binary system of intermediate mass. Methods: We gathered 25 high-resolution spectropolarimetric observations of HD 5550 using the instrument Narval. We first fitted the intensity spectra using Zeeman/ATLAS9 LTE synthetic spectra to estimate the effective temperatures, microturbulent velocities, and the abundances of some elements of both components, as well as the light ratio of the system. We then applied the multi-line least-square deconvolution (LSD) technique to the intensity and circularly polarised spectra, which provided us with mean LSD I and V line profiles. We fitted the Stokes I line profiles to determine the radial and projected rotational velocities of both stars. We then analysed the shape and evolution of the V profiles using the oblique rotator model to characterise the magnetic fields of both stars. Results: We confirm the Ap nature of the primary, which has previously been reported, and find that the secondary displays spectral characteristics typical of an Am star. While a magnetic field is clearly detected in the lines of the primary, no magnetic field is detected in the secondary in any of our observations. If a dipolar field were present at the surface of the Am star, its polar strength must be below 40 G. The faint variability observed in the Stokes V profiles of the Ap star allowed us to propose a rotation period of 6.84-0.39+0.61 d, which is close to the orbital period (~6.82 d), suggesting that the star is synchronised with its orbit. By fitting the variability of the V profiles, we propose that the

  11. Chandra Characterization of X-Ray Emission in the Young F-Star Binary System HD 113766

    Science.gov (United States)

    Lisse, C. M.; Christian, D. J.; Wolk, S. J.; Günther, H. M.; Chen, C. H.; Grady, C. A.

    2017-02-01

    Using Chandra, we have obtained imaging X-ray spectroscopy of the 10–16 Myr old F-star binary HD 113766. We individually resolve the 1.″4 separation binary components for the first time in the X-ray and find a total 0.3–2.0 keV luminosity of 2.2 × 1029 erg s‑1, consistent with previous RASS estimates. We find emission from the easternmost, infrared-bright, dusty member HD 113766A to be only ∼10% that of the western, infrared-faint member HD 113766B. There is no evidence for a 3rd late-type stellar or substellar member of HD 113766 with Lx > 6 × 1025 erg s‑1 within 2‧ of the binary pair. The ratio of the two stars’ X-ray luminosity is consistent with their assignments as F2V and F6V by Pecaut et al. The emission is soft for both stars, kTApec = 0.30–0.50 keV, suggesting X-rays produced by stellar rotation and/or convection in young dynamos, but not accretion or outflow shocks, which we rule out. A possible 2.8 ± 0.15 (2σ) hr modulation in the HD 113766B X-ray emission is seen, but at very low confidence and of unknown provenance. Stellar wind drag models corresponding to Lx ∼ 2 × 1029 erg s‑1 argue for a 1 mm dust particle lifetime around HD 113766B of only ∼90,0000 years, suggesting that dust around HD 113766B is quickly removed, whereas 1 mm sized dust around HD 113766A can survive for >1.5 × 106 years. At 1028–1029 erg s‑1 X-ray luminosity, astrobiologically important effects, like dust warming and X-ray photolytic organic synthesis, are likely for any circumstellar material in the HD 113766 systems.

  12. Abundance analysis of Am binaries and search for tidally driven abundance anomalies - III. HD116657, HD138213, HD155375, HD159560, HD196544 and HD204188

    CERN Document Server

    Stateva, I; Budaj, J

    2011-01-01

    We continue here the systematic abundance analysis of a sample of Am binaries in order to search for possible abundance anomalies driven by tidal interaction in these binary systems. New CCD observations in two spectral regions (6400-6500, 6660-6760 AA) of HD116657, HD138213, HD155375, HD159560, HD196544 and HD204188 were obtained. Synthetic spectrum analysis was carried out and basic stellar properties, effective temperatures, gravities, projected rotational velocities, masses, ages and abundances of several elements were determined. We conclude that all six stars are Am stars. These stars were put into the context of other Am binaries with 10 < Porb < 200 days and their abundance anomalies discussed in the context of possible tidal effects. There is clear anti-correlation of the Am peculiarities with v sin i. However, there seems to be also a correlation with the eccentricity and may be with the orbital period. The dependence on the temperature, age, mass, and microturbulence was studied as well. The ...

  13. Detailed Abundances of Planet-Hosting Wide Binaries. II. HD80606 + HD80607

    CERN Document Server

    Mack, Claude E; Schuler, Simon C; Hebb, Leslie; Pepper, Joshua A

    2016-01-01

    We present a detailed chemical abundance analysis of 15 elements in the planet-hosting wide binary system HD80606 + HD80607 using Keck/HIRES spectra. As in our previous analysis of the planet-hosting wide binary HD20782 + HD20781, we presume that these two G5 dwarf stars formed together and therefore had identical primordial abundances. In this binary, HD80606 hosts an eccentric ($e\\approx0.93$) giant planet at $\\sim$0.5 AU, but HD80607 has no detected planets. If close-in giant planets on eccentric orbits are efficient at scattering rocky planetary material into their host stars, then HD80606 should show evidence of having accreted rocky material while HD80607 should not. Here we show that the trends of abundance versus element condensation temperature for HD80606 and HD80607 are statistically indistinguishable, corroborating the recent result of Saffe et al. This could suggest that both stars accreted similar amounts of rocky material; indeed, our model for the chemical signature of rocky planet accretion i...

  14. A radio-map of the colliding winds in the very massive binary system HD 93129A

    CERN Document Server

    Benaglia, Paula; Moldon, Javier; Nelan, Ed; De Becker, Michael; Dougherty, Sean M; Koribalski, Baerbel

    2015-01-01

    Radio observations are an effective tool to discover particle acceleration regions in colliding-wind binaries, through detection of synchrotron radiation; these regions are natural laboratories for the study of relativistic particles. Wind-collision region (WCR) models can reproduce the radio continuum spectra of massive binaries that contain both thermal and non-thermal radio emission; however, key constraints for models come from high-resolution imaging. Only five WCRs have been resolved to date at radio frequencies at milliarcsec (mas) angular scales. The source HD 93129A, prototype of the very few known O2 I stars, is a promising target for study: recently, a second massive, early-type star about 50 mas away was discovered, and a non-thermal radio source detected in the region. Preliminary long-baseline array data suggest that a significant fraction of the radio emission from the system comes from a putative WCR. We sought evidence that HD 93129A is a massive binary system with colliding stellar winds tha...

  15. Chandra Characterization of X-ray Emission in the Young F-Star Binary System HD 113766

    CERN Document Server

    Lisse, C M; Wolk, S J; Günther, H M; Chen, C H; Grady, C A

    2016-01-01

    Using Chandra we have obtained imaging X-ray spectroscopy of the 10 to 16 Myr old F-star binary HD 113766. We individually resolve the binary components for the first time in the X-ray and find a total 0.3 to 2.0 keV luminosity of 2.2e29 erg/sec, consistent with previous RASS estimates. We find emission from the easternmost, infrared-bright, dusty member HD 113766A to be only 10% that of the western, infrared-faint member HD 113766B. There is no evidence for a 3rd late-type stellar or sub-stellar member of HD113766 with Lx > 6e25 erg s-1 within 2 arcmin of the binary pair. The ratio of the two stars Xray luminosity is consistent with their assignments as F2V and F6V by Pecaut et al. (2012). The emission is soft for both stars, kTApec = 0.30 to 0.50 keV, suggesting X-rays produced by stellar rotation and/or convection in young dynamos, but not accretion or outflow shocks which we rule out. A possible 2.8 +/- 0.15 (2{\\sigma}) hr modulation in the HD 113766B X-ray emission is seen, but at very low confidence and...

  16. X-ray emission from the double-binary OB-star system QZ Car (HD 93206)

    CERN Document Server

    Parkin, E R; Townsley, L K; Pittard, J M; Moffat, A F J; Naze, Y; Rauw, G; Oskinova, L M

    2011-01-01

    X-ray observations of the double-binary OB-star system QZ Car (HD 93206) obtained with the Chandra X-ray Observatory over a period of roughly 2 years are presented. The orbit of systems A (O9.7 I+b2 v, PA = 21 d) and B (O8 III+o9 v, PB = 6 d) are reasonably well sampled by the observations, allowing the origin of the X-ray emission to be examined in detail. The X-ray spectra can be well fitted by an attenuated three temperature thermal plasma model, characterised by cool, moderate, and hot plasma components at kT ~ 0.2, 0.7, and 2 keV, respectively, and a circumstellar absorption of ~ 0.2 x 10^22 cm-2. Although the hot plasma component could be indicating the presence of wind-wind collision shocks in the system, the model fluxes calculated from spectral fits, with an average value of ~ 7 x 10^-13 erg s-1 cm-2, do not show a clear correlation with the orbits of the two constituent binaries. A semi-analytical model of QZ Car reveals that a stable momentum balance may not be established in either system A or B. ...

  17. Radio detection of the young binary HD 160934

    CERN Document Server

    Azulay, R; Marcaide, J M; Marti-Vidal, I; Arroyo-Torres, B

    2013-01-01

    Precise determination of dynamical masses of pre-main-sequence (PMS) stars is essential to calibrate stellar evolution models that are widely used to derive theoretical masses of young low-mass objects. Binary stars in young, nearby loose associations are particularly good candidates for this calibration since all members share a common age. Interestingly, some of these young binaries present a persistent and compact radio emission, which makes them excellent targets for astrometric VLBI studies. We aim to monitor the orbital motion of the binary system HD 160934, a member of the AB Doradus moving group. We observed HD 160934 with the Very Large Array and the European VLBI Network at 8.4 and 5 GHz, respectively. The orbital information derived from these observations was analyzed along with previously reported orbital measurements. We show that the two components of the binary, HD 160934 A and HD 160934 c, display compact radio emission at VLBI scales, providing precise information on the relative orbit. Revi...

  18. Radio detection of the young binary HD 160934

    Science.gov (United States)

    Azulay, R.; Guirado, J. C.; Marcaide, J. M.; Martí-Vidal, I.; Arroyo-Torres, B.

    2014-01-01

    Context. Precise determination of dynamical masses of pre-main-sequence (PMS) stars is essential to calibrate stellar evolution models that are widely used to derive theoretical masses of young low-mass objects. Binary stars in young, nearby loose associations are particularly good candidates for this calibration since all members share a common age. Interestingly, some of these young binaries present a persistent and compact radio emission, which makes them excellent targets for astrometric VLBI studies. Aims: We aim to monitor the orbital motion of the binary system HD 160934, a member of the AB Doradus moving group. Methods: We observed HD 160934 with the Very Large Array and the European VLBI Network at 8.4 and 5 GHz, respectively. The orbital information derived from these observations was analyzed along with previously reported orbital measurements. Results: We show that the two components of the binary, HD 160934 A and HD 160934 c, display compact radio emission at VLBI scales, providing precise information on the relative orbit. Revised orbital elements were estimated. Conclusions: Future VLBI monitoring of this pair should determine precise model-independent mass estimates for the A and c components, which will serve as calibration tests for PMS evolutionary models.

  19. On the Nature of the LBV/WR Eclipsing Binary System HD 5980

    Directory of Open Access Journals (Sweden)

    G. Koenigsberger

    2004-01-01

    Full Text Available Se presenta un análisis del sistema múltiple HD 5980 situado en la Nube Menor de Magallanes y de los efectos de la colisión entre los vientos, y se discute su posible ubicación en el diagrama H-R. Los datos analizados comprenden el período 1979-2002 y son consistentes con la clasificación original WNE de la estrella B, la compañera cercana de la estrella A que en 1993-1994 tuvo una erupción. La evolución del sistema probablemente se pueda describir utilizando trazas evolutivas que incluyan los efectos de rotación y/o el intercambio de masa.

  20. ALMA view of the circumstellar environment of the post-common-envelope-evolution binary system HD101584

    CERN Document Server

    Olofsson, H; Maercker, M; Humphreys, E M L; Lindqvist, M; Nyman, L; Ramstedt, S

    2015-01-01

    We study the circumstellar evolution of the binary HD101584, consisting of a post-AGB star and a low-mass companion, which is most likely a post-common-envelope-evolution system. We used ALMA observations of the 12CO, 13CO, and C18O J=2-1 lines and the 1.3mm continuum to determine the morphology, kinematics, masses, and energetics of the circumstellar environment. The circumstellar medium has a bipolar hour-glass structure, seen almost pole-on, formed by an energetic jet, about 150 km/s. We conjecture that the circumstellar morphology is related to an event that took place about 500 year ago, possibly a capture event where the companion spiraled in towards the AGB star. However, the kinetic energy of the accelerated gas exceeds the released orbital energy, and, taking into account the expected energy transfer efficiency of the process, the observed phenomenon does not match current common-envelope scenarios. This suggests that another process must augment, or even dominate, the ejection process. A significant...

  1. X-ray and optical observations of the unique binary system HD49798/RXJ0648.0-4418

    CERN Document Server

    Mereghetti, S; Tiengo, A; Pizzolato, F; Esposito, P; Woudt, P A; Israel, G L; Stella, L

    2011-01-01

    We report the results of XMM-Newton observations of HD49798/RXJ0648.0-4418, the only known X-ray binary consisting of a hot sub-dwarf and a white dwarf. The white dwarf rotates very rapidly (P=13.2 s) and has a dynamically measured mass of 1.28+/-0.05 M_sun. Its X-ray emission consists of a strongly pulsed, soft component, well fit by a blackbody with kT~40 eV, accounting for most of the luminosity, and a fainter hard power-law component (photon index ~1.6). A luminosity of ~10^{32} erg/s is produced by accretion onto the white dwarf of the helium-rich matter from the wind of the companion, which is one of the few hot sub-dwarfs showing evidence of mass-loss. A search for optical pulsations at the South African Astronomical Observatory 1.9-m telescope gave negative results. X-rays were detected also during the white dwarf eclipse. This emission, with luminosity 2x10^{30} erg/s, can be attributed to HD 49798 and represents the first detection of a hot sub-dwarf star in the X-ray band. HD49798/RXJ0648.0-4418 is...

  2. Kepler Observations of the Asteroseismic Binary HD 176465

    CERN Document Server

    White, T R; Aguirre, V Silva; Ball, W H; Bedding, T R; Chaplin, W J; Christensen-Dalsgaard, J; Garcia, R A; Gizon, L; Stello, D; Aigrain, S; Antia, H M; Appourchaux, T; Bazot, M; Campante, T L; Creevey, O L; Davies, G R; Elsworth, Y P; Gaulme, P; Handberg, R; Hekker, S; Houdek, G; Howe, R; Huber, D; Karoff, C; Marques, J P; Mathur, S; McQuillan, A; Metcalfe, T S; Mosser, B; Nielsen, M B; Régulo, C; Salabert, D; Stahn, T

    2016-01-01

    Binary star systems are important for understanding stellar structure and evolution, and are especially useful when oscillations can be detected and analysed with asteroseismology. However, only four systems are known in which solar-like oscillations are detected in both components. Here, we analyse the fifth such system, HD 176465, which was observed by Kepler. We carefully analysed the system's power spectrum to measure individual mode frequencies, adapting our methods where necessary to accommodate the fact that both stars oscillate in a similar frequency range. We also modelled the two stars independently by fitting stellar models to the frequencies and complementary parameters. We are able to cleanly separate the oscillation modes in both systems. The stellar models produce compatible ages and initial compositions for the stars, as is expected from their common and contemporaneous origin. Combining the individual ages, the system is about 3.0$\\pm$0.5 Gyr old. The two components of HD 176465 are young phy...

  3. Precise radial velocities of giant stars. IX. HD 59686 Ab: a massive circumstellar planet orbiting a giant star in a 13.6 au eccentric binary system

    Science.gov (United States)

    Ortiz, Mauricio; Reffert, Sabine; Trifonov, Trifon; Quirrenbach, Andreas; Mitchell, David S.; Nowak, Grzegorz; Buenzli, Esther; Zimmerman, Neil; Bonnefoy, Mickaël; Skemer, Andy; Defrère, Denis; Lee, Man Hoi; Fischer, Debra A.; Hinz, Philip M.

    2016-10-01

    Context. For over 12 yr, we have carried out a precise radial velocity (RV) survey of a sample of 373 G- and K-giant stars using the Hamilton Échelle Spectrograph at the Lick Observatory. There are, among others, a number of multiple planetary systems in our sample as well as several planetary candidates in stellar binaries. Aims: We aim at detecting and characterizing substellar and stellar companions to the giant star HD 59686 A (HR 2877, HIP 36616). Methods: We obtained high-precision RV measurements of the star HD 59686 A. By fitting a Keplerian model to the periodic changes in the RVs, we can assess the nature of companions in the system. To distinguish between RV variations that are due to non-radial pulsation or stellar spots, we used infrared RVs taken with the CRIRES spectrograph at the Very Large Telescope. Additionally, to characterize the system in more detail, we obtained high-resolution images with LMIRCam at the Large Binocular Telescope. Results: We report the probable discovery of a giant planet with a mass of mp sin i = 6.92-0.24+0.18 MJup orbiting at ap = 1.0860-0.0007+0.0006 au from the giant star HD 59686 A. In addition to the planetary signal, we discovered an eccentric (eB = 0.729-0.003+0.004) binary companion with a mass of mB sin i = 0.5296-0.0008+0.0011 M⊙ orbiting at a close separation from the giant primary with a semi-major axis of aB = 13.56-0.14+0.18 au. Conclusions: The existence of the planet HD 59686 Ab in a tight eccentric binary system severely challenges standard giant planet formation theories and requires substantial improvements to such theories in tight binaries. Otherwise, alternative planet formation scenarios such as second-generation planets or dynamical interactions in an early phase of the system's lifetime need to be seriously considered to better understand the origin of this enigmatic planet. Based on observations collected at the Lick Observatory, University of California.Based on observations collected at the

  4. HD 174884: a strongly eccentric, short-period early-type binary system discovered by CoRoT

    CERN Document Server

    Maceroni, C; Michel, E; Harmanec, P; Prsa, A; Briquet, M; Niemczura, E; Morel, T; Ladjal, D; Auvergne, M; Baglin, A; Baudin, F; Catala, C; Samadi, R; Aerts, C

    2009-01-01

    Accurate photometric CoRoT space observations of a secondary seismological target, HD 174884, led to the discovery that this star is an astrophysically important double-lined eclipsing spectroscopic binary in an eccentric orbit (e of about 0.3), unusual for its short (3.65705d) orbital period. The high eccentricity, coupled with the orientation of the binary orbit in space, explains the very unusual observed light curve with strongly unequal primary and secondary eclipses having the depth ratio of 1-to-100 in the CoRoT 'seismo' passband. Without the high accuracy of the CoRoT photometry, the secondary eclipse, 1.5 mmag deep, would have gone unnoticed. A spectroscopic follow-up program provided 45 high dispersion spectra. The analysis of the CoRoT light curve was performed with an adapted version of PHOEBE that supports CoRoT passbands. The final solution was obtained by simultaneous fitting of the light and the radial velocity curves. Individual star spectra were derived by spectrum disentangling. The uncerta...

  5. HD 30187 B and HD 39927 B: Two suspected nearby hot subdwarfs in resolved binaries (based on observations made with the ESA Hipparcos satellite)

    DEFF Research Database (Denmark)

    Makarov, V.V.; Fabricius, C.

    1999-01-01

    Stars: Individual: HD 30187 B -- Stars: Individual: HD 39927 B - Stars: White dwarfs - Stars: Binaries: Visual......Stars: Individual: HD 30187 B -- Stars: Individual: HD 39927 B - Stars: White dwarfs - Stars: Binaries: Visual...

  6. Kepler Observations of the Asteroseismic Binary HD 176465

    DEFF Research Database (Denmark)

    White, T. R.; Benomar, O.; Silva Aguirre, V.

    2016-01-01

    Binary star systems are important for understanding stellar structure and evolution, and are especially useful when oscillations can be detected and analysed with asteroseismology. However, only four systems are known in which solar-like oscillations are detected in both components. Here, we...... analyse the fifth such system, HD 176465, which was observed by Kepler. We carefully analysed the system's power spectrum to measure individual mode frequencies, adapting our methods where necessary to accommodate the fact that both stars oscillate in a similar frequency range. We also modelled the two...... stars independently by fitting stellar models to the frequencies and complementary parameters. We are able to cleanly separate the oscillation modes in both systems. The stellar models produce compatible ages and initial compositions for the stars, as is expected from their common and contemporaneous...

  7. Precise radial velocities of giant stars IX. HD 59686 Ab: a massive circumstellar planet orbiting a giant star in a ~13.6 au eccentric binary system

    CERN Document Server

    Ortiz, Mauricio; Trifonov, Trifon; Quirrenbach, Andreas; Mitchell, David; Nowak, Grzegorz; Buenzli, Esther; Zimmerman, Neil; Bonnefoy, Mickael; Skemer, Andy; Defrère, Denis; Lee, Man Hoi; Fischer, Debra; Hinz, Philip

    2016-01-01

    Context: For over 12 years, we have carried out a precise radial velocity survey of a sample of 373 G and K giant stars using the Hamilton \\'Echelle Spectrograph at Lick Observatory. There are, among others, a number of multiple planetary systems in our sample as well as several planetary candidates in stellar binaries. Aims: We aim at detecting and characterizing substellar+stellar companions to the giant star HD 59686 A (HR 2877, HIP 36616). Methods: We obtained high precision radial velocity (RV) measurements of the star HD 59686 A. By fitting a Keplerian model to the periodic changes in the RVs, we can assess the nature of companions in the system. In order to discriminate between RV variations due to non-radial pulsation or stellar spots we used infrared RVs taken with the CRIRES spectrograph at the Very Large Telescope. Additionally, to further characterize the system, we obtain high-resolution images with LMIRCam at the Large Binocular Telescope. Results: We report the likely discovery of a giant plane...

  8. Apsidal motion in the massive binary HD152218

    CERN Document Server

    Rauw, G; Noels, A; Mahy, L; Schmitt, J H M M; Godart, M; Dupret, M -A; Gosset, E

    2016-01-01

    Massive binary systems are important laboratories in which to probe the properties of massive stars and stellar physics in general. In this context, we analysed optical spectroscopy and photometry of the eccentric short-period early-type binary HD 152218 in the young open cluster NGC 6231. We reconstructed the spectra of the individual stars using a separating code. The individual spectra were then compared with synthetic spectra obtained with the CMFGEN model atmosphere code. We furthermore analysed the light curve of the binary and used it to constrain the orbital inclination and to derive absolute masses of 19.8 +/- 1.5 and 15.0 +/- 1.1 solar masses. Combining radial velocity measurements from over 60 years, we show that the system displays apsidal motion at a rate of (2.04^{+.23}_{-.24}) degree/year. Solving the Clairaut-Radau equation, we used stellar evolution models, obtained with the CLES code, to compute the internal structure constants and to evaluate the theoretically predicted rate of apsidal moti...

  9. Orbital and physical parameters of eclipsing binaries from the ASAS catalogue - VIII. The totally-eclipsing double-giant system HD 187669

    CERN Document Server

    Hełminiak, K G; Konacki, M; Pilecki, B; Ratajczak, M; Pietrzyński, G; Sybilski, P; Villanova, S; Gieren, W; Pojmański, G; Konorski, P; Suchomska, K; Reichart, D E; Ivarsen, K M; B., J; Haislip,; LaCluyze, A P

    2014-01-01

    We present the first full orbital and physical analysis of HD 187669, recognized by the All-Sky Automated Survey (ASAS) as the eclipsing binary ASAS J195222-3233.7. We combined multi-band photometry from the ASAS and SuperWASP public archives and 0.41-m PROMPT robotic telescopes with our high-precision radial velocities from the HARPS spectrograph. Two different approaches were used for the analysis: 1) fitting to all data simultaneously with the WD code, and 2) analysing each light curve (with JKTEBOP) and RVs separately and combining the partial results at the end. This system also shows a total primary (deeper) eclipse, lasting for about 6 days. A spectrum obtained during this eclipse was used to perform atmospheric analysis with the MOOG and SME codes in order to constrain physical parameters of the secondary. We found that ASAS J195222-3233.7 is a double-lined spectroscopic binary composed of two evolved, late-type giants, with masses of $M_1 = 1.504\\pm0.004$ and $M_2=1.505\\pm0.004$ M$_\\odot$, and radii ...

  10. Very Low-Mass Stellar and Substellar Companions to Solar-like Stars From MARVELS VI: A Giant Planet and a Brown Dwarf Candidate in a Close Binary System HD 87646

    CERN Document Server

    Ma, Bo; Wolszczan, Alex; Muterspaugh, Matthew W; Lee, Brian; Henry, Gregory W; Schneider, Donald P; Martin, Eduardo L; Niedzielski, Andrzej; Xie, Jiwei; Fleming, Scott W; Thomas, Neil; Williamson, Michael; Zhu, Zhaohuan; Agol, Eric; Bizyaev, Dmitry; da Costa, Luiz Nicolaci; Jiang, Peng; Fiorenzano, A F Martinez; Hernandez, Jonay I Gonzalez; Guo, Pengcheng; Grieves, Nolan; Li, Rui; Liu, Jane; Mahadevan, Suvrath; Mazeh, Tsevi; Nguyen, Duy Cuong; Paegert, Martin; Sithajan, Sirinrat; Stassun, Keivan; Thirupathi, Sivarani; van Eyken, Julian C; Wan, Xiaoke; Wang, Ji; Wisniewski, John P; Zhao, Bo; Zucker, Shay

    2016-01-01

    We report the detections of a giant planet (MARVELS-7b) and a brown dwarf candidate (MARVELS-7c) around the primary star in the close binary system, HD 87646. It is the first close binary system with more than one substellar circum-primary companion discovered to the best of our knowledge. The detection of this giant planet was accomplished using the first multi-object Doppler instrument (KeckET) at the Sloan Digital Sky Survey (SDSS) telescope. Subsequent radial velocity observations using ET at Kitt Peak National Observatory, HRS at HET, the "Classic" spectrograph at the Automatic Spectroscopic Telescope at Fairborn Observatory, and MARVELS from SDSS-III confirmed this giant planet discovery and revealed the existence of a long-period brown dwarf in this binary. HD 87646 is a close binary with a separation of $\\sim22$ AU between the two stars, estimated using the Hipparcos catalogue and our newly acquired AO image from PALAO on the 200-inch Hale Telescope at Palomar. The primary star in the binary, HD 87646...

  11. The Multiple System HD 27638

    CERN Document Server

    Torres, G

    2005-01-01

    We report spectroscopic observations of HD 27638B, the secondary in a visual binary in which the physically associated primary (separation approximately 19 arcsec) is a B9V star. The secondary shows strong Li 6708 absorption suggesting youth, and has attracted attention in the past as a candidate post-T Tauri star although this has subsequently been ruled out. It was previously known to be a double-lined spectroscopic binary (F8+G6) with a period of 17.6 days, and to show velocity residuals indicating a more distant massive third companion with a period of at least 8 years. Based on our radial velocity measurements covering more than two cycles of the outer orbit, along with other measurements, we derive an accurate triple orbital solution giving an outer period of 9.447 +/- 0.017 yr. The third object is more massive than either of the other two components of HD 27638B, but is not apparent in the spectra. We derive absolute visual magnitudes and effective temperatures for the three visible stars in HD 27638. ...

  12. Is there a compact companion orbiting the late O-type binary star HD 164816?

    Science.gov (United States)

    Trepl, L.; Hambaryan, V. V.; Pribulla, T.; Tetzlaff, N.; Chini, R.; Neuhäuser, R.; Popov, S. B.; Stahl, O.; Walter, F. M.; Hohle, M. M.

    2012-12-01

    We present a multi-wavelength (X-ray, γ-ray, optical and radio) study of HD 164816, a late O-type X-ray detected spectroscopic binary. X-ray spectra are analysed and the X-ray photon arrival times are checked for pulsation. In addition, newly obtained optical spectroscopic monitoring data on HD 164816 are presented. They are complemented by available radio data from several large-scale surveys as well as the Fermi γ-ray data from its Large Area Telescope. We report the detection of a low energy excess in the X-ray spectrum that can be described by a simple absorbed blackbody model with a temperature of ˜50 eV as well as a 9.78 s pulsation of the X-ray source. The soft X-ray excess, the X-ray pulsation and the kinematical age would all be consistent with a compact object like a neutron star as companion to HD 164816. The size of the soft X-ray excess emitting area is consistent with a circular region with a radius of about 7 km, typical for neutron stars, while the emission measure (EM) of the remaining harder emission is typical for late O-type single or binary stars. If HD 164816 includes a neutron star born in a supernova, this supernova should have been very recent and should have given the system a kick, which is consistent with the observation that the star HD 164816 has a significantly different radial velocity than the cluster mean. In addition we confirm the binarity of HD 164816 itself by obtaining an orbital period of 3.82 d, projected masses m1sin3i = 2.355(69) M⊙, m2sin3i = 2.103(62) M⊙ apparently seen at low inclination angle, determined from high-resolution optical spectra.

  13. A model for the non-thermal emission of the very massive colliding-wind binary HD 93129A

    OpenAIRE

    del Palacio, Santiago; Bosch-Ramon, Valentí; Romero, Gustavo E.; Benaglia, Paula

    2016-01-01

    The binary stellar system HD 93129A is one of the most massive known binaries in our Galaxy. This system presents non-thermal emission in the radio band, which can be used to infer its physical conditions and predict its emission in the high-energy band. We intend to constrain some of the unknown parameters of HD 93129A through modelling the non-thermal emitter, and also to analyse the detectability of this source in hard X-rays and $\\gamma$-rays. We develop a broadband radiative model for th...

  14. Velocity Curve Analysis of Spectroscopic Binary Stars AI Phe, GM Dra, HD 93917 and V502 Oph by Nonlinear Regression

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    We introduce a new method to derive the orbital parameters of spectroscopic binary stars by nonlinear least squares of (o - c). Using the measured radial velocity data of the four double lined spectroscopic binary systems,AI Phe,GM Dra,HD 93917 and V502 Oph,we derived both the orbital and combined spectroscopic elements of these systems.Our numerical results are in good agreement with the those obtained using the method of Lehmann-Filhés.

  15. The young binary HD 102077: Orbit, spectral type, kinematics, and moving group membership

    CERN Document Server

    Wöllert, Maria; Reffert, Sabine; Schlieder, Joshua E; Mohler-Fischer, Maren; Köhler, Rainer; Henning, Thomas

    2014-01-01

    The K-type binary star HD 102077 was proposed as a candidate member of the TW Hydrae Association (TWA) which is a young (5-15 Myr) moving group in close proximity (~50 pc) to the solar system. The aim of this work is to verify this hypothesis by different means. We first combine diffraction-limited observations from the ESO NTT 3.5m telescope in SDSS-i' and -z' passbands and ESO 3.6m telescope in H-band with literature data to obtain a new, amended orbit fit, estimate the spectral types of both components, and reanalyse the Hipparcos parallax and proper motion taking the orbital motion into account. Moreover, we use two high-resolution spectra of HD 102077 obtained with the fibre-fed optical echelle spectrograph FEROS at the MPG/ESO 2.2m telescope to determine the radial velocity and the lithium equivalent width of the system. The trajectory of HD 102077 is well constrained and we derive a total system mass of $2.6 \\pm 0.8\\,$ M$_{\\odot}$ and a semi-major axis of $14.9 \\pm 1.6\\,$AU. From the i'-z' colours we i...

  16. The massive double-lined O-type binary HD 165052

    CERN Document Server

    Arias, J I; Barba, R H; Bosch, G L; Grosso, M; Corcoran, M

    2002-01-01

    We present a new optical spectroscopic study of the O-type binary HD 165052 based on high- and intermediate-resolution CCD observations. We re-investigated the spectral classification of the binary components, obtaining spectral types of O6.5 V and O7.5 V for the primary and secondary, respectively, finding that both stars display weak C {\\sc iii} $\\lambda5696$ emission in their spectra. We also determined a radial-velocity orbit for HD 165052 with a period of 2.95510 $\\pm$ 0.00001 d, and semiamplitudes of 94.8 and 104.7 $\\pm$ 0.5 km s$^{-1}$, resulting in a mass ratio $Q = 0.9$. From a comparison with previous radial-velocity determinations, we found evidence of apsidal motion in the system. Several signatures of wind-wind collision, such as phase-locked variability of the X-ray flux and the Struve-Sahade effect, are also considered. It was also found that the reddening in the region should be normal, in contrast with previous determinations.

  17. HD314884: A Slowly Pulsating B star in a Close Binary

    CERN Document Server

    Johnson, Christopher B; Maccarone, T; Britt, C T; Davis, H; Jonker, P G; Torres, M A P; Steeghs, D; Greiss, S; Nelemans, G

    2014-01-01

    We present the results of a spectroscopic and photometric analysis of HD314884, a slowly pulsating B star (SPB) in a binary system with detected soft X-ray emission. We spectrally classify the B star as a B5V-B6V star with T$_{eff}$ = 15,490 $\\pm$ 310 K, log $g$ = 3.75 $\\pm$ 0.25 dex, and a photometric period of P$_{0}$ = 0.889521(12) days. A spectroscopic period search reveals an orbital period for the system of P$_{orb}$ = 1.3654(11) days. The discrepancy in the two periods and the identification of a second and third distinct frequency in the photometric fourier transform at P$_1$ = 3.1347(56) and P$_2$ = 1.517(28) days provides evidence that HD314884 is a slowly pulsating B star (SPB) with at least three oscillation frequencies. These frequencies appear to originate from higher-order, non-linear tidal pulsations. Using the dynamical parameters obtained from the radial velocity curve, we find the most probable companion mass to be M$_1$ = $\\sim$0.8 M$_{\\odot}$ assuming a typical mass for the B star and mos...

  18. A model for the non-thermal emission of the very massive colliding-wind binary HD 93129A

    CERN Document Server

    del Palacio, Santiago; Romero, Gustavo E; Benaglia, Paula

    2016-01-01

    The binary stellar system HD 93129A is one of the most massive known binaries in our Galaxy. This system presents non-thermal emission in the radio band, which can be used to infer its physical conditions and predict its emission in the high-energy band. We intend to constrain some of the unknown parameters of HD 93129A through modelling the non-thermal emitter, and also to analyse the detectability of this source in hard X-rays and $\\gamma$-rays. We develop a broadband radiative model for the wind-collision region taking into account the evolution of the accelerated particles streaming along the shocked region, the emission by different radiative processes, and the attenuation of the emission propagating through the local matter and radiation fields. From the analysis of the radio emission, we find that the binary HD~93129A is more likely to have a low inclination and a high eccentricity. The minimum energy of the non-thermal electrons seems to be between $\\sim 20 - 100$MeV, depending on the intensity of the...

  19. New precision orbits of bright double-lined spectroscopic binaries. IX. HD 54371, HR 2692, and 16 ursa majoris

    Energy Technology Data Exchange (ETDEWEB)

    Fekel, Francis C.; Williamson, Michael H.; Muterspaugh, Matthew W. [Center of Excellence in Information Systems, Tennessee State University, 3500 John A. Merritt Boulevard, Box 9501, Nashville, TN 37209 (United States); Pourbaix, Dimitri [FNRS Institut d’Astronomie et d’Astrophysique, Université Libre de Bruxelles, CP 226, B-1050 Bruxelles (Belgium); Willmarth, Daryl [Kitt Peak National Obsevatory, P.O. Box 26732, Tucson, AZ 85726-6732 (United States); Tomkin, Jocelyn, E-mail: fekel@evans.tsuniv.edu, E-mail: michael.h.williamson@gmail.com, E-mail: matthew1@coe.tsuniv.edu, E-mail: pourbaix@astro.ulb.ac.be, E-mail: dwillmarth@noao.edu [Astronomy Department and McDonald Observatory, University of Texas, Austin, TX 78712 (United States)

    2015-02-01

    With extensive sets of new radial velocities we have determined orbital elements for three previously known spectroscopic binaries, HD 54371, HR 2692, and 16 UMa. All three systems have had the lines of their secondaries detected for the first time. The orbital periods range from 16.24 to 113.23 days, and the three binaries have modestly or moderately eccentric orbits. The secondary to primary mass ratios range from 0.50 to 0.64. The orbital dimensions (a{sub 1} sin i and a{sub 2} sin i) and minimum masses (m{sub 1} sin{sup 3} i and m{sub 2} sin{sup 3} i) of the binary components all have accuracies of ⩽1%. With our spectroscopic results and the Hipparcos data, we also have determined astrometric orbits for two of the three systems, HR 2692 and 16 UMa. The primaries of HD 54371 and 16 UMa are solar-type stars, and their secondaries are likely K or M dwarfs. The primary of HR 2692 is a late-type subgiant and its secondary is a G or K dwarf. The primaries of both HR 2692 and 16 UMa may be pseudosynchronously rotating, while that of HD 54371 is rotating faster than its pseudosynchronous velocity.

  20. HD183648: a Kepler eclipsing binary with anomalous ellipsoidal variations and a pulsating component

    Directory of Open Access Journals (Sweden)

    Derekas A.

    2015-01-01

    Full Text Available KIC 8560861 (HD 183648 is a marginally eccentric (e = 0.05 eclipsing binary with an orbital period of Porb = 31.973 d, exhibiting mmag amplitude pulsations on time scales of a few days. We present the results of the complex analysis of high and medium-resolution spectroscopic data and Kepler Q0 – Q16 long cadence photometry.

  1. The Herbig Ae SB2 System HD 104237

    CERN Document Server

    Cowley, Charles R; Hubrig, Swetlana

    2013-01-01

    The double-lined spectroscopic binary HD 104237 (DX Cha) is part of a complex system of some half-dozen nearby young stars. We report a significant change from an orbit for the SB2 system derived from 1999-2000 observations. We obtain abundances from the primary and secondary spectra. The abundance analysis uses both detailed spectral synthesis and determinations based on equivalent widths of weak absorption lines with W(lambda) typically < 25 mA. Abundances are derived for 25 elements in the primary, and 17 elements in the secondary. Apart from lithium and zirconium, abundances do not depart significantly from solar. Lithium may be marginally enhanced with respect to the meteoritic value in the primary. It somewhat depleted in the secondary. The emission-line spectrum is typical of Herbig Ae stars. We compare and contrast the spectra of the HD 104237 primary and two other Herbig Ae stars with low v.sin(i), HD 101412 and HD 190073.

  2. HD 210111: a new lambda Bootis type SB system

    CERN Document Server

    Paunzen, E; Fraga, L; Pintado, O

    2012-01-01

    The small group of lambda Bootis stars comprises late B to early F-type stars, with moderate to extreme (up to a factor 100) surface underabundances of most Fe-peak elements and solar abundances of lighter elements (C, N, O, and S). The main mechanisms responsible for this phenomenon are atmospheric diffusion, meridional mixing and accretion of material from their surroundings. Especially spectroscopic binary (SB) systems with lambda Bootis type components are very important to investigate the evolutionary status and accretion process in more details. For HD 210111, also delta Scuti type pulsation was found which gives the opportunity to use the tools of asteroseismology for further investigations. The latter could result in strict constraints for the amount of diffusion for this star. Together with models for the accretion and its source this provides a unique opportunity to shed more light on these important processes. We present classification and high resolution spectra for HD 210111. A detailed investiga...

  3. Spectroscopic Binaries near the North Galactic Pole Paper 24: HD 106104, 109281, 109463 and 110743

    Indian Academy of Sciences (India)

    R. F. Griffin

    2001-06-01

    The four stars treated in this paper have been under observation with photoelectric radial-velocity spectrometers for many years. They have proved to be binaries with periods of 30, 1828, 1514 and 822 days respectively; the orbits are of modest eccentricity apart from that of HD 110743 which is indistinguishable from a circle. The mass functions are small, and no companion has been observed for any of the stars. HD 110743, a K dwarf, is much the nearest of the four, and its orbit is of short enough period for the photocentric motion to have been recognized by Hipparcos. An eleventh-magnitude star rather more than 1' away from HD 106104 is shown to be a genuine physical companion, with practically identical radial velocity, proper motion and distance modulus, although the projected separation is about 13,000 AU.

  4. A Physical Orbit for the High Proper Motion Binary HD 9939

    CERN Document Server

    Boden, A F; Torres, G; Boden, Andrew F.; Latham, David W.; Torres, Guillermo

    2006-01-01

    We report spectroscopic and interferometric observations of the high-proper motion double-lined binary system HD 9939, with an orbital period of approximately 25 days. By combining our radial-velocity and visibility measurements we estimate the system physical orbit and derive dynamical masses for the components of $M_A = 1.072 \\pm 0.014$ M$_{\\sun}$ and $M_B = 0.8383 \\pm 0.0081$ M$_{\\sun}$; fractional errors of 1.3% and 1.0%, respectively. We also determine a system distance of $42.23 \\pm 0.21$ pc, corresponding to an orbital parallax of $\\pi_{\\rm orb} = 23.68 \\pm 0.12$ mas. The system distance and the estimated brightness difference between the stars in $V$, $H$, and $K$ yield component absolute magnitudes in these bands. By spectroscopic analysis and spectral energy distribution modeling we also estimate the component effective temperatures and luminosities as $T_{\\rm eff}^A = 5050 \\pm 100$ K and $T_{\\rm eff}^B = 4950 \\pm 200$ K and $L_A$ = 2.451 $\\pm$ 0.041 $L_{\\sun}$ and $L_B$ = 0.424 $\\pm$ 0.023 $L_{\\sun...

  5. Orbital parameters, chemical composition, and magnetic field of the Ap binary HD 98088

    CERN Document Server

    Folsom, C P; Wade, G A; Kochukhov, O; Alecian, E; Shulyak, D

    2013-01-01

    HD 98088 is a synchronised, double-lined spectroscopic binary system with a magnetic Ap primary component and an Am secondary component. We study this rare system using high-resolution MuSiCoS spectropolarimetric data, to gain insight into the effect of binarity on the origin of stellar magnetism and the formation of chemical peculiarities in A-type stars. Using a new collection of 29 high-resolution Stokes VQU spectra we re-derive the orbital and stellar physical parameters and conduct the first disentangling of spectroscopic observations of the system to conduct spectral analysis of the individual stellar components. From this analysis we determine the projected rotational velocities of the stars and conduct a detailed chemical abundance analysis of each component using both the SYNTH3 and ZEEMAN spectrum synthesis codes. The surface abundances of the primary component are typical of a cool Ap star, while those of the secondary component are typical of an Am star. We present the first magnetic analysis of b...

  6. Pre-main-sequence binaries with tidally disrupted discs: the Br gamma in HD 104237

    CERN Document Server

    Garcia, P J V; Dougados, C; Bacciotti, F; Clausse, J -M; Massi, F; Mérand, A; Petrov, R; Weigelt, G

    2013-01-01

    Active pre-main-sequence binaries with separations of around ten stellar radii present a wealth of phenomena unobserved in common systems. The study of these objects is extended from Classical T Tauri stars to the Herbig Ae star HD 104237. Spectro-interferometry with the VLTI/AMBER is presented. It is found that the K-band continuum squared visibilities are compatible with a circumbinary disc with a radius of ~0.5 AU. However, a significant fraction (~50 per cent) of the flux is unresolved and not fully accounted by the stellar photospheres. The stars probably don't hold circumstellar discs, in addition to the circumbinary disk, due to the combined effects of inner magnetospheric truncation and outer tidal truncation. This unresolved flux likely arises in compact structures inside the tidally disrupted circumbinary disc. Most ($\\gtrsim 90$ per cent) of the Br gamma line emission is unresolved. The line-to-continuum spectro-astrometry shifts in time, along the direction of the Ly alpha jet known to be driven b...

  7. The B-Supergiant Components of the Double-Lined Binary HD1383

    CERN Document Server

    Boyajian, T S; Helsel, M E; Kaye, A B; McSwain, M V; Riddle, R L; Wingert, D W

    2006-01-01

    We present new results from a study of high quality, red spectra of the massive binary star system HD 1383 (B0.5 Ib + B0.5 Ib). We determined radial velocities and revised orbital elements (P = 20.28184 +/- 0.0002 d) and made Doppler tomographic reconstructions of the component spectra. A comparison of these with model spectra from non-LTE, line blanketed atmospheres indicates that both stars have almost identical masses (M_2/M_1 = 1.020 +/- 0.014), temperatures (T_eff = 28000 +/- 1000 K), gravities (log g = 3.25 +/- 0.25), and projected rotational velocities (V sin i < 30 km/s). We investigate a number of constraints on the radii and masses of the stars based upon the absence of eclipses, surface gravity, stellar wind terminal velocity, and probable location in the Perseus spiral arm of the Galaxy, and these indicate a range in probable radius and mass of R/R_sun = 14 - 20 and M/M_sun = 16 - 35, respectively. These values are consistent with model evolutionary masses for single stars of this temperature a...

  8. HD 85567: A Herbig B[e] star or an interacting B[e] binary

    CERN Document Server

    Wheelwright, H E; Garatti, A Caratti o; Lopez, R Garcia

    2013-01-01

    Context. HD 85567 is an enigmatic object exhibiting the B[e] phenomenon, i.e. an infrared excess and forbidden emission lines in the optical. The object's evolutionary status is uncertain and there are conflicting claims that it is either a young stellar object or an evolved, interacting binary. Aims. To elucidate the reason for the B[e] behaviour of HD 85567, we have observed it with the VLTI and AMBER. Methods. Our observations were conducted in the K-band with moderate spectral resolution (R~1500, i.e. 200 km/s). The spectrum of HD 85567 exhibits Br gamma and CO overtone bandhead emission. The interferometric data obtained consist of spectrally dispersed visibilities, closure phases and differential phases across these spectral features and the K-band continuum. Results. The closure phase observations do not reveal evidence of asymmetry. The apparent size of HD 85567 in the K-band was determined by fitting the visibilities with a ring model. The best fitting radius, 0.8 +/- 0.3 AU, is relatively small maki...

  9. Spectroscopic and photometric analysis of the early-type spectroscopic binary HD 161853 in the centre of an H II region

    CERN Document Server

    Gamen, R; Barbá, R H; Arias, J I; Apellániz, J Maíz; Walborn, N R; Sota, A; Alfaro, E J

    2015-01-01

    We study the O-type star HD 161853, which has been noted as a probable double-lined spectroscopic binary system. We secured high-resolution spectra of HD 161853 during the past nine years. We separated the two components in the system and measured their respective radial velocities for the first time. We confirm that HD 161853 is an $\\sim$1 Ma old binary system consisting of an O8 V star ($M_{\\rm A,RV} \\geq 22$ M$_\\odot$) and a B1--3 V star ($M_{\\rm B,RV} \\geq 7.2$ M$_\\odot$) at about 1.3 kpc. From the radial velocity curve, we measure an orbital period $P$ = 2.66765$\\pm$0.00001 d and an eccentricity $e$ = 0.121$\\pm$0.007. Its $V$-band light curve is constant within 0.014 mag and does not display eclipses, from which we impose a maximum orbital inclination $i=54$ deg. HD 161853 is probably associated with an H II region and a poorly investigated very young open cluster. In addition, we detect a compact emission region at 50 arcsec to HD 161853 in 22$\\mu$m-WISE and 24$\\mu$m-Spitzer images, which may be identif...

  10. Binary-induced magnetic activity? Time-series echelle spectroscopy and photometry of HD123351 = CZ CVn

    CERN Document Server

    Strassmeier, K G; Weber, M; Granzer, T; Bartus, J; Olah, K; Rice, J B

    2011-01-01

    We present a first and detailed study of the bright and active K0IV-III star HD 123351. The star is found to be a single-lined spectroscopic binary with a period of 147.8919+-0.0003 days and a large eccentricity of e=0.8086+-0.0001. The rms of the orbital solution is just 47 m/s, making it the most precise orbit ever obtained for an active binary system. The rotation period is constrained from long-term photometry to be 58.32+-0.01 days. It shows that HD 123351 is a very asynchronous rotator, rotating five times slower than the expected pseudo-synchronous value. Two spotted regions persisted throughout the 12 years of our observations. Four years of Halpha, CaII H&K and HeI D3 monitoring identifies the same main periodicity as the photometry but dynamic spectra also indicate that there is an intermittent dependence on the orbital period, in particular for Ca ii H&K in 2008. Line-profile inversions of a pair of Zeeman sensitive/insensitive iron lines yield an average surface magnetic-flux density of 54...

  11. Is there a compact companion orbiting the late O-type binary star HD 164816?

    CERN Document Server

    Trepl, L; Pribulla, T; Tetzlaff, N; Chini, R; Neuhäuser, R; Popov, S B; Stahl, O; Walter, F M; Hohle, M M

    2012-01-01

    We present a multi-wavelength (X-ray, $\\gamma$-ray, optical and radio) study of HD 194816, a late O-type X-ray detected spectroscopic binary. X-ray spectra are analyzed and the X-ray photon arrival times are checked for pulsation. In addition, newly obtained optical spectroscopic monitoring data on HD 164816 are presented. They are complemented by available radio data from several large scale surveys as well as the \\emph{FERMI} $\\gamma$-ray data from its \\emph{Large Area Telescope}. We report the detection of a low energy excess in the X-ray spectrum that can be described by a simple absorbed blackbody model with a temperature of $\\sim$ 50 eV as well as a 9.78 s pulsation of the X-ray source. The soft X-ray excess, the X-ray pulsation, and the kinematical age would all be consistent with a compact object like a neutron star as companion to HD 164816. The size of the soft X-ray excess emitting area is consistent with a circular region with a radius of about 7 km, typical for neutron stars, while the emission m...

  12. Against all odds? Forming the planet of the HD196885 binary

    CERN Document Server

    Thebault, Philippe

    2011-01-01

    HD196885Ab is the most "extreme" planet-in-a-binary discovered to date, whose orbit places it at the limit for orbital stability. The presence of a planet in such a highly perturbed region poses a clear challenge to planet-formation scenarios. We investigate this issue by focusing on the planet-formation stage that is arguably the most sensitive to binary perturbations: the mutual accretion of kilometre-sized planetesimals. To this effect we numerically estimate the impact velocities $dv$ amongst a population of circumprimary planetesimals. We find that most of the circumprimary disc is strongly hostile to planetesimal accretion, especially the region around 2.6AU (the planet's location) where binary perturbations induce planetesimal-shattering $dv$ of more than 1km/s. Possible solutions to the paradox of having a planet in such accretion-hostile regions are 1) that initial planetesimals were very big, at least 250km, 2) that the binary had an initial orbit at least twice the present one, and was later compac...

  13. Velocity Curve Analysis of the Spectroscopic Binary Stars PV Pup, HD 141929, EE Cet and V921 Her by Nonlinear Regression

    Indian Academy of Sciences (India)

    K. Karami; R. Mohebi

    2007-12-01

    We use the method introduced by Karami & Mohebi (2007), and Karami & Teimoorinia (2007) which enable us to derive the orbital parameters of the spectroscopic binary stars by the nonlinear least squares of observed . curve fitting (o–c). Using the measured experimental data for radial velocities of the four double-lined spectroscopic binary systems PV Pup, HD 141929, EE Cet and V921 Her, we find both the orbital and the combined spectroscopic elements of these systems. Our numerical results are in good agreement with those obtained using the method of Lehmann-Filhés.

  14. HD 164492C: a rapidly-rotating, H$\\alpha$-bright, magnetic early B star associated with a 12.5d spectroscopic binary

    CERN Document Server

    Wade, G A; Sikora, J; Bernier, M -É; Rivinius, Th; Alecian, E; Petit, V; Grunhut, J H

    2016-01-01

    We employ high resolution spectroscopy and spectropolarimetry to derive the physical properties and magnetic characteristics of the multiple system HD 164492C, located in the young open cluster M20. The spectrum reveals evidence of 3 components: a broad-lined early B star (HD 164492C1), a narrow-lined early B star (HD 164492C2), and a late B star (HD 164492C3). Components C2 and C3 exhibit significant ($>100$ km/s) bulk radial velocity variations with a period of $12.5351(7)$ d that we attribute to eccentric binary motion around a common centre-of-mass. Component C1 exhibits no detectable radial velocity variations. Using constraints derived from modeling the orbit of the C2+C3 binary and from synthesis of the combined spectrum, we determine the approximate physical characteristics of the components. We conclude that a coherent evolutionary solution consistent with the published age of M20 implies a distance to the system of $0.9\\pm 0.2$ kpc, corresponding to the smallest published values. We confirm the dete...

  15. Calculation of the Masses of the Binary Star HD 93205 by Application of the Theory of the Apsidal Motion

    CERN Document Server

    Benvenuto, O G; Althaus, L G; Barba, R H; Morrell, N I

    2002-01-01

    We present a method to calculate masses for components of both eclipsing and non-eclipsing binary systems as long as their apsidal motion rates are available. The method is based on the fact that the equation that gives the rate of apsidal motion is a supplementary equation that allows the computation of the masses of the components, if the radii and the internal structure constants of them can be obtained from theoretical models. For this reason the use of this equation makes the method presented here model dependent. We apply this method to calculate the mass of the components of the non-eclipsing massive binary system HD 93205 (O3V+O8V), which is suspected to be a very young system. To this end, we computed a grid of evolutionary models covering the mass range of interest, and taking the mass of the primary (M_1) as the only independent variable, we solve the equation of apsidal motion for M_1 as a function of the age of the system. The mass of the primary we find ranges from M_1= 60+-19 msun for ZAMS mode...

  16. Unravelling the Nature of HD 81032 – A New RS CVn Binary

    Indian Academy of Sciences (India)

    J. C. Pandey; K. P. Singh; S. A. Drake; R. Sagar

    2005-12-01

    BVR photometric and quasi-simultaneous optical spectroscopic observations of the star HD 81032 have been carried out during the years 2000–2004. A photometric period of 18.802 ± 0.07d has been detected for this star. A large group of spots with a migration period of 7.43 ± 0.07 years is inferred from the first three years of the data. H and CaII H and K emissions from the star indicate high chromospheric activity. The available photometry in the BVRIJHK bands is consistent with the spectral type of K0IV previously found for this star.We have also examined the spectral energy distribution of HD 81032 for the presence of an infrared colour excess using the 2MASS JHK and IRAS photometry, but found no significant excess in any band above the normal values expected for a star with this spectral type. We have also analyzed the X-ray emission properties of this star using data obtained by the ROSAT X-ray observatory during its All-Sky Survey phase. An X-ray flare of about 12 hours duration was detected during the two days of X-ray coverage obtained for this star. Its X-ray spectrum, while only containing 345 counts, is inconsistent with a single-temperature component solar-abundance coronal plasma model, but implies either the presence of two or more plasma components, non-solar abundances, or a combination of both of these properties. All of the above properties of HD 81032 suggest that it is a newly identified, evolved RS CVn binary.

  17. Discovery of a magnetic field in the B pulsating system HD 1976

    CERN Document Server

    Neiner, C

    2014-01-01

    The presence of a magnetic field can have a strong impact on the evolution of a binary star. However, only a dozen of magnetic OB binaries are known as of today and available to study this effect, including very few magnetic pulsating spectroscopic OB binaries. We aim at checking for the presence of a magnetic field in the B5IV hierarchical triple system HD 1976 with spectropolarimetric data obtained with Narval at the Bernard Lyot Telescope (TBL). We use orbital parameters of HD 1976 available in the literature to disentangle the Narval intensity spectra. We compute Stokes V profiles with the Least Square Deconvolution (LSD) technique to search for magnetic signatures. We then derive an estimate of the longitudinal magnetic field strength for each observation and for various line lists. Our disentangling of the intensity spectra shows that HD 1976 is a double-lined spectroscopic (SB2) binary, with the lines of the secondary component about twice broader than the ones of the primary component. We do not ident...

  18. High-precision broad-band linear polarimetry of early-type binaries I. Discovery of variable, phase-locked polarization in HD 48099

    CERN Document Server

    Berdyugin, A; Sadegi, S; Tsygankov, S; Sakanoi, T; Kagitani, M; Yoneda, M; Okano, S; Poutanen, J

    2016-01-01

    We investigate the structure of the O-type binary system HD 48099 by measuring linear polarization that arises due to light scattering process. Linear polarization measurements of HD 48099 in the B, V and R passbands with the high-precision Dipol-2 polarimeter have been carried out. The data have been obtained with the 60 cm KVA (Observatory Roque de los Muchachos, La Palma, Spain) and T60 (Haleakala, Hawaii, USA) remotely controlled telescopes during 31 observing nights. Polarimetry in the optical wavelengths has been complemented by observations in the X-rays with the SWIFT space observatory. Optical polarimetry revealed small intrinsic polarization in HD 48099 with 0.1% peak to peak variation over the orbital period of 3.08 days. The variability pattern is typical for binary systems, showing strong second harmonic of the orbital period. We apply our model code for the electron scattering in the circumstellar matter to put constraints on the system geometry. A good model fit is obtained for scattering of li...

  19. Resolving Close Encounters: Stability in the HD 5319 and HD 7924 Planetary Systems

    CERN Document Server

    Kane, Stephen R

    2016-01-01

    Radial velocity searches for exoplanets have detected many multi-planet systems around nearby bright stars. An advantage of this technique is that it generally samples the orbit outside of inferior/superior conjunction, potentially allowing the Keplerian elements of eccentricity and argument of periastron to be well characterized. The orbital architectures for some of these systems show signs of close planetary encounters that may render the systems unstable as described. We provide an in-depth analysis of two such systems: HD 5319 and HD 7924, for which the scenario of coplanar orbits results in rapid destabilization of the systems. The poorly constrained periastron arguments of the outer planets in these systems further emphasizes the need for detailed investigations. An exhaustive scan of parameters space via dynamical simulations reveals specific mutual inclinations between the two outer planets in each system that allow for stable configurations over long timescales. We compare these configurations with ...

  20. Extensive study of HD 25558, a long-period double-lined binary with two SPB components

    OpenAIRE

    Sodor, A.; De Cat, P.; Wright, D J; Neiner, C.; Briquet, M.; Lampens, P.; Dukes, R. J.; Henry, G. W.; Williamson, M.H.; Brunsden, E.; Pollard, K.R.; Cottrell, P. L.; Maisonneuve, F.; Kilmartin, P.M.; Matthews, J

    2014-01-01

    We carried out an extensive observational study of the Slowly Pulsating B (SPB) star, HD 25558. The ~2000 spectra obtained at different observatories, the ground-based and MOST satellite light curves revealed that this object is a double-lined spectroscopic binary with an orbital period of about 9 years. The observations do not allow the inference of an orbital solution. We determined the physical parameters of the components, and found that both lie within the SPB instability strip. Accordin...

  1. A model for the non-thermal emission of the very massive colliding-wind binary HD 93129A

    Science.gov (United States)

    del Palacio, S.; Romero, G. E.; Bosch-Ramon, V.; Benaglia, P.

    2016-08-01

    Recently, the wind collision region of the system HD 93129A was resolved for the first time using very large baseline interferometry. This system is one of the most massive known binaries in our Galaxy. In this work we develop a broadband radiative model for the wind collision region. The model takes into account the evolution of accelerated particles streaming along the shocked region, their emission through different radiative processes, and the attenuation of the radiation while it propagates across all local fields. We reproduce the available radio data, and analyze the consequent detectability of the source in hard X/gamma-rays. We predict how the emission from the system will evolve in the forthcoming years when the stars come closer, and we also provide synthetic radio maps that allow to interpret the future observations with very large baseline interferometry in 2.3 GHz and 8.6 GHz. According to our results, the non-thermal emission from this system will enhance in the near future. With instruments such as NuSTAR, Fermi, and CTA, it will be possible to determine whether the relativistic particle content is hadron or lepton dominated, and other parameters such as the strength of the magnetic field in the wind collision region and, indirectly, the magnetic field in the surface of the very massive stars.

  2. Evolution of Close Binary Systems

    Energy Technology Data Exchange (ETDEWEB)

    Yakut, K; Eggleton, P

    2005-01-24

    We collected data on the masses, radii, etc. of three classes of close binary stars: low-temperature contact binaries (LTCBs), near-contact binaries (NCBs), and detached close binaries (DCBs). They restrict themselves to systems where (1) both components are, at least arguably, near the Main Sequence, (2) the periods are less than a day, and (3) there is both spectroscopic and photometric analysis leading to reasonably reliable data. They discuss the possible evolutionary connections between these three classes, emphasizing the roles played by mass loss and angular momentum loss in rapidly-rotating cool stars.

  3. HD 164492C: a rapidly rotating, Hα-bright, magnetic early B star associated with a 12.5 d spectroscopic binary

    Science.gov (United States)

    Wade, G. A.; Shultz, M.; Sikora, J.; Bernier, M.-É.; Rivinius, Th.; Alecian, E.; Petit, V.; Grunhut, J. H.; BinaMIcS Collaboration

    2017-03-01

    We employ high-resolution spectroscopy and spectropolarimetry to derive the physical properties and magnetic characteristics of the multiple system HD 164492C, located in the young open cluster M20. The spectrum reveals evidence of three components: a broad-lined early B star (HD 164492C1), a narrow-lined early B star (HD 164492C2) and a late B star (HD 164492C3). Components C2 and C3 exhibit significant (>100 km s-1) bulk radial velocity variations with a period of 12.5351(7) d that we attribute to eccentric binary motion around a common centre-of-mass. Component C1 exhibits no detectable radial velocity variations. Using constraints derived from modelling the orbit of the C2+C3 binary and from synthesis of the combined spectrum, we determine the approximate physical characteristics of the components. We conclude that a coherent evolutionary solution consistent with the published age of M20 implies a distance to M20 of 0.9 ± 0.2 kpc, corresponding to the smallest published values. We confirm the detection of a strong magnetic field in the combined spectrum. The field is clearly associated with the broad-lined C1 component of the system. Repeated measurement of the longitudinal magnetic field allows the derivation of the rotation period of the magnetic star, Prot = 1.369 86(6) d. We derive the star's magnetic geometry, finding i=63± 6°, β =33± 6° and a dipole polar strength B_d=7.9^{+1.2}_{-1.0} kG. Strong emission - varying according to the magnetic period - is detected in the Hα profile. This is consistent with the presence of a centrifugal magnetosphere surrounding the rapidly rotating magnetic C1 component.

  4. Spin Correlation in Binary Systems

    CERN Document Server

    Farbiash, N; Farbiash, Netzach; Steinitz, Raphael

    2004-01-01

    We examine the correlation of projected rotational velocities in binary systems. It is an extension of previous work (Steinitz and Pyper, 1970; Levato, 1974). An enlarged data basis and new tests enable us to conclude that there is indeed correlation between the projected rotational velocities of components of binaries. In fact we suggest that spins are already correlated.

  5. CALCULATING THE HABITABLE ZONE OF BINARY STAR SYSTEMS. I. S-TYPE BINARIES

    Energy Technology Data Exchange (ETDEWEB)

    Kaltenegger, Lisa [MPIA, Koenigstuhl 17, D-69117 Heidelberg (Germany); Haghighipour, Nader, E-mail: kaltenegger@mpia.de [Institute for Astronomy and NASA Astrobiology Institute, University of Hawaii-Manoa, Honolulu, HI 96822 (United States)

    2013-11-10

    We have developed a comprehensive methodology for calculating the boundaries of the habitable zone (HZ) of planet-hosting S-type binary star systems. Our approach is general and takes into account the contribution of both stars to the location and extent of the binary HZ with different stellar spectral types. We have studied how the binary eccentricity and stellar energy distribution affect the extent of the HZ. Results indicate that in binaries where the combination of mass-ratio and orbital eccentricity allows planet formation around a star of the system to proceed successfully, the effect of a less luminous secondary on the location of the primary's HZ is generally negligible. However, when the secondary is more luminous, it can influence the extent of the HZ. We present the details of the derivations of our methodology and discuss its application to the binary HZ around the primary and secondary main-sequence stars of an FF, MM, and FM binary, as well as two known planet-hosting binaries α Cen AB and HD 196886.

  6. Stability and Formation of the Resonant System HD 73526

    CERN Document Server

    Sándor, Z; Klagyivik, P

    2007-01-01

    Based on radial velocity measurements it has been found recently that the two giant planets detected around the star HD 73526 are in 2:1 resonance. However, as our numerical integration shows, the derived orbital data for this system result in chaotic behavior of the giant planets, which is uncommon among the resonant extrasolar planetary systems. We intend to present regular (non-chaotic) orbital solutions for the giant planets in the system HD 73526 and offer formation scenarios based on combining planetary migration and sudden perturbative effects such as planet-planet scattering or rapid dispersal of the protoplanetary disk. A comparison with the already studied resonant system HD 128311, exhibiting similar behavior, is also done. The new sets of orbital solutions have been derived by the Systemic Console (www.oklo.org). The stability of these solutions has been investigated by the Relative Lyapunov indicator, while the migration and scattering effects are studied by gravitational N-body simulations apply...

  7. An interferometric-spectroscopic orbit for the binary HD 195987 Testing models of stellar evolution for metal-poor stars

    CERN Document Server

    Torres, G; Latham, D W; Pan, M; Stefanik, R P; Torres, Guillermo; Boden, Andrew F.; Latham, David W.; Pan, Margaret; Stefanik, Robert P.

    2002-01-01

    We report spectroscopic and interferometric observations of the moderately metal-poor double-lined binary system HD 195987, with an orbital period of 57.3 days. By combining our radial-velocity and visibility measurements we determine the orbital elements and derive absolute masses for the components of M(A) = 0.844 +/- 0.018 Msun and M(B) = 0.6650 +/- 0.0079 Msun, with relative errors of 2% and 1%, respectively. We also determine the orbital parallax, pi(orb) = 46.08 +/- 0.27 mas, corresponding to a distance of 21.70 +/- 0.13 pc. The parallax and the measured brightness difference between the stars in V, H, and K yield the component absolute magnitudes in those bands. We also estimate the effective temperatures of the stars as Teff(A) = 5200 +/- 100 K and Teff(B) = 4200 +/- 200 K. Together with detailed chemical abundance analyses from the literature giving [Fe/H] approximately -0.5 (corrected for binarity) and [alpha/Fe] = +0.36, we use these physical properties to test current models of stellar evolution f...

  8. Discs in misaligned binary systems

    CERN Document Server

    Rawiraswattana, Krisada; Goodwin, Simon P

    2016-01-01

    We perform SPH simulations to study precession and changes in alignment between the circumprimary disc and the binary orbit in misaligned binary systems. We find that the precession process can be described by the rigid-disc approximation, where the disc is considered as a rigid body interacting with the binary companion only gravitationally. Precession also causes change in alignment between the rotational axis of the disc and the spin axis of the primary star. This type of alignment is of great important for explaining the origin of spin-orbit misaligned planetary systems. However, we find that the rigid-disc approximation fails to describe changes in alignment between the disc and the binary orbit. This is because the alignment process is a consequence of interactions that involve the fluidity of the disc, such as the tidal interaction and the encounter interaction. Furthermore, simulation results show that there are not only alignment processes, which bring the components towards alignment, but also anti-...

  9. Residue arithmetic in binary systems

    OpenAIRE

    Barsi, Ferruccio

    1988-01-01

    A natural approach to the problem of performing mod m computations in a binary system is presented and a solution is suggested which is based upon a straightforward relation between the residues of a same integer X with respect to different moduli. The proposed solution proves fruitful in various applications, such as converting binary integers to residue notation and mod m addition or multiplication. Even if the most usual implementation approach for mod m processors is based on look-up tabl...

  10. Evolution of Binaries in Dense Stellar Systems

    CERN Document Server

    Ivanova, Natalia

    2011-01-01

    In contrast to the field, the binaries in dense stellar systems are frequently not primordial, and could be either dynamically formed or significantly altered from their primordial states. Destruction and formation of binaries occur in parallel all the time. The destruction, which constantly removes soft binaries from a binary pool, works as an energy sink and could be a reason for cluster entering the binary-burning phase. The true binary fraction is greater than observed, as a result, the observable binary fraction evolves differently from the predictions. Combined measurements of binary fractions in globular clusters suggest that most of the clusters are still core-contracting. The formation, on other hand, affects most the more evolutionary advanced stars, which significantly enhances the population of X-ray sources in globular clusters. The formation of binaries with a compact objects proceeds mainly through physical collisions, binary-binary and single-binary encounters; however, it is the dynamical for...

  11. Three-dimensional orbits of the triple-O stellar system HD 150136

    CERN Document Server

    Sana, H; Mahy, L; Absil, O; De Becker, M; Gosset, E

    2013-01-01

    Context. HD 150136 is a triple hierarchical system and a non-thermal radio emitter. It is formed by an O3-3.5 V + O5.5-6 V close binary and a more distant O6.5-7 V tertiary. So far, only the inner orbital properties have been reliably constrained. Aims. To quantitatively understand the non-thermal emission process, accurate knowledge of the physical and orbital properties of the object is crucial. Here, we aim to investigate the orbital properties of the wide system and to constrain the inclinations of the inner and outer binaries, and with these the absolute masses of the system components. Methods. We used the PIONIER combiner at the Very Large Telescope Interferometer to obtain the very first interferometric measurements of HD 150136. We combined the interferometric observations with new and existing high resolution spectroscopic data to derive the orbital solution of the outer companion in the three-dimensional space. Results. The wide system is clearly resolved by PIONIER, with a projected separation on ...

  12. Fundamental parameters of the close interacting binary HD170582 and its luminous accretion disc

    CERN Document Server

    Mennickent, R E; Cabezas, M; Cséki, A; G., J Rosales; Niemczura, E; Araya, I; Curé, M

    2015-01-01

    We present a spectroscopic and photometric study of the Double Period Variable HD170582. Based on the study of the ASAS V-band light curve we determine an improved orbital period of 16.87177 $\\pm$ 0.02084 days and a long period of 587 days. We disentangled the light curve into an orbital part, determining ephemerides and revealing orbital ellipsoidal variability with unequal maxima, and a long cycle, showing quasi-sinusoidal changes with amplitude $\\Delta V$= 0.1 mag. Assuming synchronous rotation for the cool stellar component and semi-detached configuration we find a cool evolved star of $M_{2}$ = 1.9 $\\pm$ 0.1 $M_{\\odot}$, $T_{2}$ = 8000 $\\pm$ 100 $K$ and $R_{2}$ = 15.6 $\\pm$ 0.2 $R_{\\odot}$, and an early B-type dwarf of $M_{1}$ = 9.0 $\\pm$ 0.2 $M_{\\odot}$. The B-type star is surrounded by a geometrically and optically thick accretion disc of radial extension 20.8 $\\pm$ 0.3 $R_{\\odot}$ contributing about 35% to the system luminosity at the $V$ band. Two extended regions located at opposite sides of the dis...

  13. A binary engine fuelling HD87643' s complex circumstellar environment, using AMBER/VLTI

    CERN Document Server

    Millour, Florentin; Borges-Fernandes, Marcelo; Meilland, Anthony; Mars, Gilbert; Benoist, C; Thiébaut, E; Stee, Philippe; Hofmann, K -H; Baron, Fabien; Young, John R; Bendjoya, Philippe; Carciofi, A C; De Souza, Armando Domiciano; Driebe, Thomas; Jankov, Slobodan; Kervella, Pierre; Petrov, R G; Robbe-Dubois, Sylvie; Vakili, Farrokh; Waters, L B F M; Weigelt, Gerd

    2009-01-01

    Context. The star HD 87643, exhibiting the ?B[e] phenomenon?, has one of the most extreme infrared excesses for this object class. It harbours a large amount of both hot and cold dust, and is surrounded by an extended re?ection nebula. Aims. One of our major goals was to investigate the presence of a companion in HD87643. In addition, the presence of close dusty material was tested through a combination of multi-wavelength high spatial resolution observations. Methods. We observed HD 87643 with high spatial resolution techniques, using the near-IR AMBER/VLTI interferometer with baselines ranging from 60 m to 130 m and the mid-IR MIDI/VLTI interferometer with baselines ranging from 25 m to 65 m. These observations are complemented by NACO/VLT adaptive-optics-corrected images in the K and L-bands, ESO-2.2m optical Wide-Field Imager large-scale images in the B, V and R-bands, Results. We report the direct detection of a companion to HD 87643 by means of image synthesis using the AMBER/VLTI instrument. The presen...

  14. Searching for stable orbits in the HD 10180 planetary system

    Directory of Open Access Journals (Sweden)

    Laskar J.

    2011-02-01

    Full Text Available A planetary system with at least seven planets has been found around the star HD 10180. However, the traditional Keplerian and n-body fits to the data provide an orbital solution that becomes unstable very quickly, which may quest the reliability of the observations. Here we show that stable orbital configurations can be obtained if general relativity and long-term dissipation raised by tides on the innermost planet are taken into account.

  15. Three-dimensional orbits of the triple-O stellar system HD 150136

    Science.gov (United States)

    Sana, H.; Le Bouquin, J.-B.; Mahy, L.; Absil, O.; De Becker, M.; Gosset, E.

    2013-05-01

    Context. HD 150136 is a triple hierarchical system and a non-thermal radio emitter. It is formed by an O3-3.5 V + O5.5-6 V close binary and a more distant O6.5-7 V tertiary. So far, only the inner orbital properties have been reliably constrained. Aims: To quantitatively understand the non-thermal emission process, accurate knowledge of the physical and orbital properties of the object is crucial. Here, we aim to investigate the orbital properties of the wide system and to constrain the inclinations of the inner and outer binaries, and with these the absolute masses of the system components. Methods: We used the PIONIER combiner at the Very Large Telescope Interferometer to obtain the very first interferometric measurements of HD 150136. We combined the interferometric observations with new and existing high-resolution spectroscopic data to derive the orbital solution of the outer companion in the three-dimensional space. Results: The wide system is clearly resolved by PIONIER, with a projected separation on the plane of the sky of about 9 milli-arcsec. The best-fit orbital period, eccentricity, and inclination are 8.2 yr, 0.73, and 108°. We constrain the masses of the three stars of the system to 63 ± 10, 40 ± 6, and 33 ± 12 M⊙ for the O3-3.5 V, O5.5-6 V, and O6.5-7 V components. Conclusions: The dynamical masses agree within errors with the evolutionary masses of the components. Future interferometric and spectroscopic monitoring of HD 150136 should allow one to reduce the uncertainties to a few per cent only and to accurately constrain the distance to the system. This makes HD 150136 an ideal system to quantitatively test evolutionary models of high-mass stars as well as the physics of non-thermal processes occurring in O-type systems. Based on observations collected at the European Southern Observatory (ESO) under program IDs 089.D-0730 and 189.C-0644.

  16. THE FIRST ORBITAL SOLUTION FOR THE MASSIVE COLLIDING-WIND BINARY HD 93162 (-WR 25

    Directory of Open Access Journals (Sweden)

    R. Gamen

    2008-01-01

    Full Text Available Luego de que, mediante observaciones del satélite EINSTEIN, se descubriera la existencia de intensa emisión de rayos X asociada a HD 93162 (WR 25, reiteradamente se ha supuesto que esta estrella debería formar parte de un sistema binario con colisión de vientos. Sin embargo, hasta ahora no se hablan detectado variaciones de velocidad radial que permitieran demostrar esta hipótesis. Con el objeto de explorar la posible naturaleza binaria de HD 93162, la hemos observado espectroscópicamente desde el año 1994 hasta la fecha, encontrando variaciones periódicas de su velocidad radial que demuestran que WR 25 es un sistema binario de alta excentricidad, con un período orbital cercano a los 208 días.

  17. The Apsidal Alignment of the HD 82943 System

    CERN Document Server

    Jianghui, J; Lin, L; Guangyu, L; Nakai, H; Jianghui, Ji; Lin, Liu; Guangyu, Li

    2003-01-01

    We perform numerical simulations to explore the dynamical evolution of the HD 82943 planetary system. By simulating diverse planetary configurations, we find two mechanisms to maintain the stability of the system: the 2:1 mean motion resonance between the planets can act as the first mechanism for all stable orbits. The second mechanism is the apsidal alignment and we find that the difference of the apsidal longitudes $\\theta_{3}$ librates about $180^{\\circ}$ in the simulations. We also use the analytical model to explain the numerical results for the system.

  18. Recent results on the hierarchical triple system HD 150136

    Science.gov (United States)

    Gosset, E.; Berger, J. P.; Absil, O.; Le Bouquin, J. B.; Sana, H.; Mahy, L.; De Becker, M.

    2013-06-01

    HD 150136 is a hierarchical triple system, non-thermal radio emitter, made of three O stars totalling some 130 solar masses. The 2.67-day inner orbit is rather well-known. Recent works derived a good approximation for the outer orbit with a period of 3000 days. We report here on interferometric observations that allow us to angularly resolve the outer orbit. First evidences for an astrometric displacement are given. The determination of the outer system orbit gives access to the inclinations of the systems and to the masses, including the one of the O3-O3.5 primary star.

  19. Detailed Abundances of Planet-Hosting Wide Binaries. I. Did Planet Formation Imprint Chemical Signatures in the Atmospheres of HD 20782/81?

    CERN Document Server

    Mack, Claude E; Stassun, Keivan G; Pepper, Joshua; Norris, John

    2014-01-01

    Using high-resolution echelle spectra obtained with Magellan/MIKE, we present a chemical abundance analysis of both stars in the planet-hosting wide binary system HD20782 + HD20781. Both stars are G dwarfs, and presumably coeval, forming in the same molecular cloud. Therefore we expect that they should possess the same bulk metallicities. Furthermore, both stars also host giant planets on eccentric orbits with pericenters $\\lesssim 0.2\\,$ AU. We investigate if planets with such orbits could lead to the host stars ingesting material, which in turn may leave similar chemical imprints in their atmospheric abundances. We derived abundances of 15 elements spanning a range of condensation temperatures ($T_{C}\\approx 40-1660\\,$ K). The two stars are found to have a mean element-to-element abundance difference of $0.04\\pm0.07\\,$ dex, which is consistent with both stars having identical bulk metallicities. In addition, for both stars, the refractory elements ($T_{C} > 900\\,$ K) exhibit a positive correlation between a...

  20. Application of a probabilistic neural network in analysis of the radial velocity curve of spectroscopic binary stars

    Institute of Scientific and Technical Information of China (English)

    Kamal Ghaderi; Kayoomars Karami; Ali Pirkhedri; Hamid Haj Seyyed Javadi; Touba Rostami

    2012-01-01

    Using measured radial velocity data of five double-lined spectroscopic binary systems,HD 89959,HD 143705,HD 146361,HD 165052 and HD 152248,we find corresponding orbital and spectroscopic elements via a Probabilistic Neural Network.Our numerical results are in good agreement with those obtained by others using more traditional methods.

  1. On the inclination and habitability of the HD 10180 system

    Energy Technology Data Exchange (ETDEWEB)

    Kane, Stephen R. [Department of Physics and Astronomy, San Francisco State University, 1600 Holloway Avenue, San Francisco, CA 94132 (United States); Gelino, Dawn M., E-mail: skane@sfsu.edu [NASA Exoplanet Science Institute, Caltech, MS 100-22, 770 South Wilson Avenue, Pasadena, CA 91125 (United States)

    2014-09-10

    There are numerous multi-planet systems that have now been detected via a variety of techniques. These systems exhibit a range of both planetary properties and orbital configurations. For those systems without detected planetary transits, a significant unknown factor is the orbital inclination. This produces an uncertainty in the mass of the planets and their related properties, such as atmospheric scale height. Here we investigate the HD 10180 system, which was discovered using the radial velocity technique. We provide a new orbital solution for the system which allows for eccentric orbits for all planets. We show how the inclination of the system affects the mass/radius properties of the planets and how the detection of phase signatures may resolve the inclination ambiguity. We finally evaluate the Habitable Zone properties of the system and show that the g planet spends 100% of an eccentric orbit within the Habitable Zone.

  2. A New Analysis of the Exoplanet Hosting System HD 6434

    CERN Document Server

    Hinkel, Natalie R; Pilyavsky, Genady; Boyajian, Tabetha S; James, David J; Naef, Dominique; Fischer, Debra A; Udry, Stephane

    2015-01-01

    The current goal of exoplanetary science is not only focused on detecting but characterizing planetary systems in hopes of understanding how they formed, evolved, and relate to the Solar System. The Transit Ephemeris Refinement and Monitoring Survey (TERMS) combines both radial velocity (RV) and photometric data in order to achieve unprecedented ground-based precision in the fundamental properties of nearby, bright, exoplanet-hosting systems. Here we discuss HD 6434 and its planet, HD 6434b, which has a M_p*sin(i) = 0.44 M_J mass and orbits every 22.0170 days with an eccentricity of 0.146. We have combined previously published RV data with new measurements to derive a predicted transit duration of ~6 hrs, or 0.25 days, and a transit probability of 4%. Additionally, we have photometrically observed the planetary system using both the 0.9m and 1.0m telescopes at the Cerro Tololo Inter-American Observatory, covering 75.4% of the predicted transit window. We reduced the data using the automated TERMS Photometry P...

  3. HD Radio发射与接收系统%Transmission and Receiving System of HD Radio

    Institute of Scientific and Technical Information of China (English)

    李栋

    2008-01-01

    在世界范围内,主流的数字声音广播除了DAB和DRM外,近年来HD Radio技术在美国得到了快速发展,其他一些国家和地区也正在进行试验,做应用的准备.HD Radio技术是用在AM和FM中的IBOC(带内同频道)技术的发展与完善,尤其是应用在FM波段的FM HD Radio技术系统,可实现模拟与数字节目同播,可使模拟FM广播平滑过渡到数字广播,设备改造投资少.首先介绍了HD Radio技术的发展现状,着重阐述了发射与接收技术系统的构成与工作原理.

  4. The Transiting Exocomets in the HD 172555 System

    Science.gov (United States)

    Grady, C. A.; Brown, A.; Kamp, I.; Roberge, A.; Riviere-Marichalar, P.; Welsh, B.

    2017-01-01

    The Earth is thought to have formed dry, in a part of the Solar Nebula deficient in organic material, and to have acquired its organics and water through bombardment by minor bodies. Observations of this process in well-dated systems can provide insight into the probable origin and composition of the bombarding parent bodies. Transiting cometary activity has previously been reported in Ca II for the late-A member of the 241 Myr old Pictoris Moving Group member, HD 172555(Kiefer et al. 2014). We present HST STIS and COS spectra of HD 172555 demonstrating that the star has chromospheric emission and variable in falling gas features in transitions of silicon and carbon ions at times when no Fe II absorption is seen in the UV data, and no Ca II absorption is seen in contemporary optical spectra. The lack of CO absorption and stable gas absorption at the system velocity is consistent with the absence of a cold Kuiper belt analog (Riviere-Marichalar et al. 2012) in this system. The presence of infall in some species at one epoch and others at different epochs suggests that, like Pictoris, there may be more than one family of exocomets. If perturbed into star-grazing orbits by the same mechanism as for Pic, these data suggest that the wide planet frequency among A-early F stars in the PMG is at least 37.5, well above the frequency estimated for young moving groups independent of host star spectral type.

  5. The unstable fate of the planet orbiting the A-star in the HD 131399 triple stellar system

    CERN Document Server

    Veras, Dimitri; Gaensicke, Boris T

    2016-01-01

    Validated planet candidates need not lie on long-term stable orbits, and instability triggered by post-main-sequence stellar evolution can generate architectures which transport rocky material to white dwarfs, polluting them. The giant planet HD 131399Ab orbits its parent A star at a projected separation of about 50-100 au. The host star, HD 131399A, is part of a hierarchical triple with HD 131399BC being a close binary separated by a few hundred au from the A star. Here, we determine the fate of this system, and find that (i) stability along the main sequence is achieved only for a favourable choice of parameters within the errors, and (ii) even for this choice, in almost every instance the planet is ejected during the transition between the giant branch and white dwarf phases of HD 131399A. This result provides an example of both how the free-floating planet population may be enhanced by similar systems, and how instability can manifest in the polluted white dwarf progenitor population.

  6. The unstable fate of the planet orbiting the A star in the HD 131399 triple stellar system

    Science.gov (United States)

    Veras, Dimitri; Mustill, Alexander J.; Gänsicke, Boris T.

    2017-02-01

    Validated planet candidates need not lie on long-term stable orbits, and instability triggered by post-main-sequence stellar evolution can generate architectures which transport rocky material to white dwarfs, hence polluting them. The giant planet HD 131399Ab orbits its parent A star at a projected separation of about 50-100 au. The host star, HD 131399A, is part of a hierarchical triple with HD 131399BC being a close binary separated by a few hundred au from the A star. Here, we determine the fate of this system, and find the following: (i) Stability along the main sequence is achieved only for a favourable choice of parameters within the errors. (ii) Even for this choice, in almost every instance, the planet is ejected during the transition between the giant branch and white dwarf phases of HD 131399A. This result provides an example of both how the free-floating planet population may be enhanced by similar systems and how instability can manifest in the polluted white dwarf progenitor population.

  7. Refined Properties of the HD 130322 Planetary System

    CERN Document Server

    Hinkel, Natalie R; Henry, Gregory W; Feng, Y Katherina; Boyajian, Tabetha; Wright, Jason; Fischer, Debra A; Howard, Andrew W

    2015-01-01

    Exoplanetary systems closest to the Sun, with the brightest host stars, provide the most favorable opportunities for characterization studies of the host star and their planet(s). The Transit Ephemeris Refinement and Monitoring Survey uses both new radial velocity measurements and photometry in order to greatly improve planetary orbit uncertainties and the fundamental properties of the star, in this case HD 130322. The only companion, HD 130322b, orbits in a relatively circular orbit, e = 0.029 every ~10.7 days. Radial velocity measurements from multiple sources, including 12 unpublished from the Keck I telescope, over the course of ~14 years have reduced the uncertainty in the transit midpoint to ~2 hours. The transit probability for the b-companion is 4.7%, where M_p sin i = 1.15 M_J and a = 0.0925 AU. In this paper, we compile photometric data from the T11 0.8m Automated Photoelectric Telescope at Fairborn Observatory taken over ~14 years, including the constrained transit window, which results in a dispos...

  8. A Six-Planet System Orbiting HD 219134

    CERN Document Server

    Vogt, Steven S; Meschiari, Stefano; Butler, R Paul; Henry, Gregory W; Wang, Songhu; Holden, Brad; Gapp, Cyril; Hanson, Russell; Arriagada, Pamela; Keiser, Sandy; Teske, Johanna; Laughlin, Gregory

    2015-01-01

    We present new, high-precision Doppler radial velocity (RV) data sets for the nearby K3V star HD 219134. The data include 175 velocities obtained with the HIRES Spectrograph at the Keck I Telescope, and 101 velocities obtained with the Levy Spectrograph at the Automated Planet Finder Telescope (APF) at Lick Observatory. Our observations reveal six new planetary candidates, with orbital periods of P=3.1, 6.8, 22.8, 46.7, 94.2 and 2247 days, spanning masses of msini=3.8, 3.5, 8.9, 21.3, 10.8 and 108 M_earth respectively. Our analysis indicates that the outermost signal is unlikely to be an artifact induced by stellar activity. In addition, several years of precision photometry with the T10 0.8~m automatic photometric telescope (APT) at Fairborn Observatory demonstrated a lack of brightness variability to a limit of ~0.0002 mag, providing strong support for planetary-reflex motion as the source of the radial velocity variations. The HD 219134 system, with its bright (V=5.6) primary provides an excellent opportun...

  9. HD172481 a super lithium-rich metal-deficient post-AGB binary with a red AGB companion

    CERN Document Server

    Reyniers, M; Reyniers, Maarten; Winckel, Hans Van

    2000-01-01

    We present in this paper a study on the peculiar supergiant HD172481. Its spectral type (F2Ia), high galactic latitude (b=-10.37), circumstellar dust, high radial velocity and moderate metal deficiency ([Fe/H]=-0.55) confirm the post-AGB character of this object. A detailed chemical analysis shows slight but real s-process overabundances, however no CNO-enhancement was detected. Furthermore, the spectral energy distribution and the TiO bands in the red part of the spectrum reveal a red luminous companion. The luminosity ratio of the hot F type component and this cool M type companion L(F)/L(M) is derived for a reddening of E(B-V)=0.44 (L(F)/L(M)=1.8) and indicates that the companion must also be strongly evolved and probably evolving along the AGB. Neither our photometric data-set, nor our radial velocity monitoring show evidence for orbital variability which may indicate that the period is too large for direct binary interaction. Most interestingly, a strong lithium resonance line is detected, which yields a...

  10. Extensive study of HD 25558, a long-period double-lined binary with two SPB components

    CERN Document Server

    Sódor, Á; Wright, D J; Neiner, C; Briquet, M; Lampens, P; Dukes, R J; Henry, G W; Williamson, M H; Brunsden, E; Pollard, K R; Cottrell, P L; Maisonneuve, F; Kilmartin, P M; Matthews, J; Kallinger, T; Beck, P G; Kambe, E; Engelbrecht, C A; Czanik, R J; Yang, S; Hashimoto, O; Honda, S; Fu, J N; Castanheira, B; Lehmann, H; Bognár, Zs; Behara, N; Scaringi, S; Van Winckel, H; Menu, J; Lobel, A; Mathias, P; Saesen, S; Vučković, M

    2013-01-01

    We carried out an extensive observational study of the Slowly Pulsating B (SPB) star, HD 25558. The ~2000 spectra obtained at different observatories, the ground-based and MOST satellite light curves revealed that this object is a double-lined spectroscopic binary with an orbital period of about 9 years. The observations do not allow the inference of an orbital solution. We determined the physical parameters of the components, and found that both lie within the SPB instability strip. Accordingly, both show line-profile variations due to stellar pulsations. Eleven independent frequencies were identified in the data. All the frequencies were attributed to one of the two components based on Pixel-by-pixel variability analysis of the line profiles. Spectroscopic and photometric mode identification was also performed for the frequencies of both stars. These results suggest that the inclination and rotation of the two components are rather different. The primary is a slow rotator with ~6 d period, seen at ~60 deg i...

  11. The Transiting Exocomets in the HD 172555 System

    Science.gov (United States)

    Grady, C. A.; Brown, Alexander; Kamp, Inga; Roberge, Aki; Riviere-Marichalar, Pablo; Welsh, Barry

    2017-01-01

    The Earth is thought to have formed dry, in a part of the Solar Nebula deficient in organic material, and to have acquired its water and organics through bombardment by minor bodies. Observations of this process in well-dated systems can provide insight into the probable origin and composition of the bombarding parent bodies. Transiting cometary activity has previously been reported in Ca II for the late-A member of the ~23 Myr old Beta Pictoris Moving Group member, HD 172555. We present HST STIS and COS spectra of HD 172555 which demonstrate that the star has chromospheric emission and variable infalling gas features in transitions of silicon and carbon ions at times when no Fe II absorption is seen in the UV data, and no Ca II absorption is seen in contemporary optical spectra. We discuss apparent optical depths for the infall features. The lack of CO absorption and stable gas absorption at the system velocity is consistent with the absence of a cold Kuiper belt analog in this system. The presence of infall in some species at one epoch and others at different epochs suggests that, like beta Pictoris, there may be more than one family of exocomets. If perturbed into star-grazing orbits by the same mechanism as for beta Pic, these data suggest that the wide planet frequency among A-early F stars in the BPMG is at least 37.5%, well above the frequency estimated for young moving groups independent of host star spectral type.Support for this work was provided by NASA through grant Number HST-GO-13798 from the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS5-26555.

  12. H/D Isotope Effects in Hydrogen Bonded Systems

    Directory of Open Access Journals (Sweden)

    Aleksander Filarowski

    2013-04-01

    Full Text Available An extremely strong H/D isotope effect observed in hydrogen bonded A-H…B systems is connected with a reach diversity of the potential shape for the proton/deuteron motion. It is connected with the anharmonicity of the proton/deuteron vibrations and of the tunneling effect, particularly in cases of short bridges with low barrier for protonic and deuteronic jumping. Six extreme shapes of the proton motion are presented starting from the state without possibility of the proton transfer up to the state with a full ionization. The manifestations of the H/D isotope effect are best reflected in the infra-red absorption spectra. A most characteristic is the run of the relationship between the isotopic ratio nH/nD and position of the absorption band shown by using the example of NHN hydrogen bonds. One can distinguish a critical range of correlation when the isotopic ratio reaches the value of ca. 1 and then increases up to unusual values higher than . The critical range of the isotope effect is also visible in NQR and NMR spectra. In the critical region one observes a stepwise change of the NQR frequency reaching 1.1 MHz. In the case of NMR, the maximal isotope effect is reflected on the curve presenting the dependence of Δd (1H,2H on d (1H. This effect corresponds to the range of maximum on the correlation curve between dH and ΔpKa that is observed in various systems. There is a lack in the literature of quantitative information about the influence of isotopic substitution on the dielectric properties of hydrogen bond except the isotope effect on the ferroelectric phase transition in some hydrogen bonded crystals.

  13. Evolutionary Memory in Binary Systems?

    CERN Document Server

    Steinitz, N F R

    2004-01-01

    Correlation between the spins (rotational velocities) in binaries has previously been established. We now continue and show that the degree of spin correlation is independent of the components' separation. Such a result might be related for example to Zhang's non-linear model for the formation of binary stars from a nebula.

  14. Evolution of non-synchronized binary systems

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A model for binary evolution is introduced which can determine whether the rotation of components is synchronized with the orbital motion, and can calculate the evolution of both the synchronized and non-synchronized binary systems. With this model, the evolution of a binary system consisting of a 9 M⊙ star and a 6 M⊙ star is studied with mass transfer Case B. The result shows that the synchronization of the rotational and orbital periods can be reached when the binary system is a detached system and before the occurrence of the first mass transfer. After the onset of the first mass transfer, the binary system becomes non-synchronized. The mass accepted component (the secondary) rotates faster with a period much smaller than that of the orbital motion.

  15. Evolution of non-synchronized binary systems

    Institute of Scientific and Technical Information of China (English)

    黄润乾; 曾艺蓉

    2000-01-01

    A model for binary evolution is introduced which can determine whether the rotation of components is synchronized with the orbital motion, and can calculate the evolution of both the synchronized and non-synchronized binary systems. With this model, the evolution of a binary system consisting of a 9 M star and a 6 M star is studied with mass transfer Case B. The result shows that the synchronization of the rotational and orbital periods can be reached when the binary system is a detached system and before the occurrence of the first mass transfer. After the onset of the first mass transfer, the binary system becomes non-synchronized. The mass accepted component (the secondary) rotates faster with a period much smaller than that of the orbital motion.

  16. Terrestrial Planet Formation in Binary Star Systems

    Science.gov (United States)

    Lissauer, J. J.; Quintana, E. V.; Adams, F. C.; Chambers, J. E.

    2006-01-01

    Most stars reside in binary/multiple star systems; however, previous models of planet formation have studied growth of bodies orbiting an isolated single star. Disk material has been observed around one or both components of various young close binary star systems. If planets form at the right places within such disks, they can remain dynamically stable for very long times. We have simulated the late stages of growth of terrestrial planets in both circumbinary disks around 'close' binary star systems with stellar separations ($a_B$) in the range 0.05 AU $\\le a_B \\le$ 0.4 AU and binary eccentricities in the range $0 \\le e \\le 0.8$ and circumstellar disks around individual stars with binary separations of tens of AU. The initial disk of planetary embryos is the same as that used for simulating the late stages of terrestrial planet growth within our Solar System and around individual stars in the Alpha Centauri system (Quintana et al. 2002, A.J., 576, 982); giant planets analogous to Jupiter and Saturn are included if their orbits are stable. The planetary systems formed around close binaries with stellar apastron distances less than or equal to 0.2 AU with small stellar eccentricities are very similar to those formed in the Sun-Jupiter-Saturn, whereas planetary systems formed around binaries with larger maximum separations tend to be sparser, with fewer planets, especially interior to 1 AU. Likewise, when the binary periastron exceeds 10 AU, terrestrial planets can form over essentially the entire range of orbits allowed for single stars with Jupiter-like planets, although fewer terrestrial planets tend to form within high eccentricity binary systems. As the binary periastron decreases, the radial extent of the terrestrial planet systems is reduced accordingly. When the periastron is 5 AU, the formation of Earth-like planets near 1 AU is compromised.

  17. On the possibility of habitable Trojan planets in binary star systems

    CERN Document Server

    Schwarz, Richard; Bazsó, Ákos

    2016-01-01

    Approximately 60 percent of all stars in the solar neighbourhood (up to 80 percent in our Milky Way) are members of binary or multiple star systems. This fact led to the speculations that many more planets may exist in binary systems than are currently known. To estimate the habitability of exoplanetary systems, we have to define the so-called habitable zone (HZ). The HZ is defined as a region around a star where a planet would receive enough radiation to maintain liquid water on its surface and to be able to build a stable atmosphere. We search for new dynamical configurations - where planets may stay in stable orbits - to increase the probability to find a planet like the Earth. Therefore we investigated five candidates and found that two systems (HD 41004 and HD 196885) which have small stable regions.

  18. Tomographic Separation of Composite Spectra. XII. The Physical Properties and Spectral Phase Variability of the Massive Close Binary HD 159176

    Science.gov (United States)

    Penny, Laura R.; Epps, Jacob G.; Snyder, Joseph D.

    2016-12-01

    We present our analysis of the double-lined, O-binary HD 159176 based on observations made with the International Ultraviolet Explorer (IUE). We use cross-correlation methods to obtain radial velocities, confirm the orbital elements, and estimate the UV flux ratio. In addition, we cross-correlate specific regions of the IUE spectra corresponding to Fe v, Fe iv, He ii, N iii, and O iv features to determine the phase dependence of the cross-correlation strength for those features. We tomographically reconstruct the individual component spectra, which we classify as O6.5 V + O7 V. We present the first light-curve analysis of observations from the HIPPARCOS satellite combined with data from Thomas & Pachoulakis and determine an orbital inclination, i=43\\buildrel{\\circ}\\over{.} 5+/- 4\\buildrel{\\circ}\\over{.} 5. Both stars are well within their Roche surfaces. Our derived masses, {M}p/{M}⊙ =46.4{+/- }9.514.3 and {M}s/{M}⊙ =44.{+/- }9.113.6, are constrained by the known distance and reddening to NGC 6383 and the derived optical flux ratio, and agree within errors with predicted evolutionary masses. Both components display phase variations corresponding to the classical Struve-Sahade effect in the UV, Fe iv, N iii, and O iv cross-correlation functions. The Fe v features have remarkably uniform profile strengths except in observations prior to conjunctions, a possible post-quadrature Struve-Sahade effect. The derived orbital elements from the various ions are not affected by the Struve-Sahade variability. Both the spectral variability and derived orbital semi-amplitudes of He ii λ 1640 suggest that this feature is formed preferentially on the inner hemispheres of the component stars.

  19. Discovery of a magnetic field in the rapidly-rotating O-type secondary of the colliding-wind binary HD 47129 (Plaskett's star)

    CERN Document Server

    Grunhut, J H; Leutenegger, M; Petit, V; Rauw, G; Neiner, C; Martins, F; Cohen, D H; Gagné, M; Ignace, R; Mathis, S; de Mink, S E; Moffat, A F J; Owocki, S; Shultz, M; Sundqvist, J

    2012-01-01

    We report the detection of a strong, organized magnetic field in the secondary component of the massive O8III/I+O7.5V/III double-lined spectroscopic binary system HD 47129 (Plaskett's star), in the context of the Magnetism in Massive Stars (MiMeS) survey. Eight independent Stokes $V$ observations were acquired using the ESPaDOnS spectropolarimeter at the Canada-France-Hawaii Telescope and the Narval spectropolarimeter at the T\\'elescope Bernard Lyot. Using Least-Squares Deconvolution we obtain definite detections of signal in Stokes $V$ in 3 observations. No significant signal is detected in the diagnostic null ($N$) spectra. The Zeeman signatures are broad and track the radial velocity of the secondary component; we therefore conclude that the rapidly-rotating secondary component is the magnetized star. Correcting the polarized spectra for the line and continuum of the (sharp-lined) primary, we measured the longitudinal magnetic field from each observation. The longitudinal field of the secondary is variable...

  20. Stability of multiplanet systems in binaries

    Science.gov (United States)

    Marzari, F.; Gallina, G.

    2016-10-01

    Context. When exploring the stability of multiplanet systems in binaries, two parameters are normally exploited: the critical semimajor axis ac computed by Holman & Wiegert (1999, AJ, 117, 621) within which planets are stable against the binary perturbations, and the Hill stability limit Δ determining the minimum separation beyond which two planets will avoid mutual close encounters. Both these parameters are derived in different contexts, i.e. Δ is usually adopted for computing the stability limit of two planets around a single star while ac is computed for a single planet in a binary system. Aims: Our aim is to test whether these two parameters can be safely applied in multiplanet systems in binaries or if their predictions fail for particular binary orbital configurations. Methods: We have used the frequency map analysis (FMA) to measure the diffusion of orbits in the phase space as an indicator of chaotic behaviour. Results: First we revisited the reliability of the empirical formula computing ac in the case of single planets in binaries and we find that, in some cases, it underestimates by 10-20% the real outer limit of stability and it does not account for planets trapped in resonance with the companion star well beyond ac. For two-planet systems, the value of Δ is close to that computed for planets around single stars, but the level of chaoticity close to it substantially increases for smaller semimajor axes and higher eccentricities of the binary orbit. In these configurations ac also begins to be unreliable and non-linear secular resonances with the stellar companion lead to chaotic behaviour well within ac, even for single planet systems. For two planet systems, the superposition of mean motion resonances, either mutual or with the binary companion, and non-linear secular resonances may lead to chaotic behaviour in all cases. We have developed a parametric semi-empirical formula determining the minimum value of the binary semimajor axis, for a given

  1. Spin-orbit misalignment in the HD 80606 planetary system

    Science.gov (United States)

    Pont, F.; Hébrard, G.; Irwin, J. M.; Bouchy, F.; Moutou, C.; Ehrenreich, D.; Guillot, T.; Aigrain, S.; Bonfils, X.; Berta, Z.; Boisse, I.; Burke, C.; Charbonneau, D.; Delfosse, X.; Desort, M.; Eggenberger, A.; Forveille, T.; Lagrange, A.-M.; Lovis, C.; Nutzman, P.; Pepe, F.; Perrier, C.; Queloz, D.; Santos, N. C.; Ségransan, D.; Udry, S.; Vidal-Madjar, A.

    2009-08-01

    We recently reported the photometric and spectroscopic detection of the primary transit of the 111-day-period, eccentric extra-solar planet HD 80606b, at Observatoire de Haute-Provence, France. The whole egress of the primary transit and a section of its central part were observed, allowing the measurement of the planetary radius, and evidence for a spin-orbit misalignment through the observation of the Rossiter-McLaughlin anomaly. The ingress not having been observed for this long-duration transit, uncertainties remained in the parameters of the system. We present here a refined, combined analysis of our photometric and spectroscopic data, together with further published radial velocities, ground-based photometry, and Spitzer photometry around the secondary eclipse, as well as new photometric measurements of HD 80606 acquired at Mount Hopkins, Arizona, just before the beginning of the primary transit. Although the transit is not detected in those new data, they provide an upper limit for the transit duration, which narrows down the possible behaviour of the Rossiter-McLaughlin anomaly in the unobserved part of the transit. We analyse the whole data with a Bayesian approach using a Markov-chain Monte Carlo integration on all available information. We find Rp = 0.98 ± 0.03 {R}_Jup for the planetary radius, and a total primary transit duration of 11.9 ± 1.3 h from first to fourth contact. Our analysis reinforces the hypothesis of spin-orbit misalignment in this system (alignment excluded at >95% level), with a positive projected angle between the planetary orbital axis and the stellar rotation (median solution λ ˜ 50°). As HD 80606 is a component of a binary system, the peculiar orbit of its planet could result from a Kozai mechanism. Based on observations made with the 1.20-m and 1.93-m telescopes at Observatoire de Haute-Provence (CNRS), France, by the SOPHIE consortium (program 07A.PNP.CONS), and with a 16-inch telescope at Mt. Hopkins, Arizona, USA, by the

  2. Dynamical Simulations of the Planetary System HD69830

    CERN Document Server

    Payne, Matthew J; Wyatt, Mark C; Booth, Mark

    2008-01-01

    HD 69830 exhibits radial velocity variations attributed to three planets as well as infrared emission attributed to a warm debris disk. Previous studies have developed models for the planet migration and mass growth (Alibert et al. 2006) and the replenishment of warm grains (Wyatt et al. 2007). We perform n-body integrations in order to explore the implications of these models for: 1) the excitation of planetary eccentricity, 2) the accretion and clearing of a putative planetesimal disk, 3) the distribution of planetesimal orbits following migration, and 4) the implications for the origin of the IR emission. We find that: i) It is not possible to explain the observed planetary eccentricities (e~0.1) purely as the result of planetary perturbations during migration unless the planetary system is nearly face-on. ii) The rate of accretion of planetesimals onto planets in our n-body simulations is significantly different to that assumed in the semi-analytic models, suggesting that one cannot successfully treat pla...

  3. The Evolution of Compact Binary Star Systems

    Directory of Open Access Journals (Sweden)

    Konstantin A. Postnov

    2014-05-01

    Full Text Available We review the formation and evolution of compact binary stars consisting of white dwarfs (WDs, neutron stars (NSs, and black holes (BHs. Mergings of compact-star binaries are expected to be the most important sources for forthcoming gravitational-wave (GW astronomy. In the first part of the review, we discuss observational manifestations of close binaries with NS and/or BH components and their merger rate, crucial points in the formation and evolution of compact stars in binary systems, including the treatment of the natal kicks, which NSs and BHs acquire during the core collapse of massive stars and the common envelope phase of binary evolution, which are most relevant to the merging rates of NS-NS, NS-BH and BH-BH binaries. The second part of the review is devoted mainly to the formation and evolution of binary WDs and their observational manifestations, including their role as progenitors of cosmologically-important thermonuclear SN Ia. We also consider AM CVn-stars, which are thought to be the best verification binary GW sources for future low-frequency GW space interferometers.

  4. The Evolution of Compact Binary Star Systems.

    Science.gov (United States)

    Postnov, Konstantin A; Yungelson, Lev R

    2014-01-01

    We review the formation and evolution of compact binary stars consisting of white dwarfs (WDs), neutron stars (NSs), and black holes (BHs). Mergings of compact-star binaries are expected to be the most important sources for forthcoming gravitational-wave (GW) astronomy. In the first part of the review, we discuss observational manifestations of close binaries with NS and/or BH components and their merger rate, crucial points in the formation and evolution of compact stars in binary systems, including the treatment of the natal kicks, which NSs and BHs acquire during the core collapse of massive stars and the common envelope phase of binary evolution, which are most relevant to the merging rates of NS-NS, NS-BH and BH-BH binaries. The second part of the review is devoted mainly to the formation and evolution of binary WDs and their observational manifestations, including their role as progenitors of cosmologically-important thermonuclear SN Ia. We also consider AM CVn-stars, which are thought to be the best verification binary GW sources for future low-frequency GW space interferometers.

  5. Detailed abundances of planet-hosting wide binaries. I. Did planet formation imprint chemical signatures in the atmospheres of HD 20782/81?

    Energy Technology Data Exchange (ETDEWEB)

    Mack III, Claude E.; Stassun, Keivan G. [Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 (United States); Schuler, Simon C. [University of Tampa, Tampa, FL 33606 (United States); Norris, John, E-mail: claude.e.mack@vanderbilt.edu [Research School of Astronomy and Astrophysics, The Australian National University, Weston, ACT 2611 (Australia)

    2014-06-01

    Using high-resolution, high signal-to-noise echelle spectra obtained with Magellan/MIKE, we present a detailed chemical abundance analysis of both stars in the planet-hosting wide binary system HD 20782 + HD 20781. Both stars are G dwarfs, and presumably coeval, forming in the same molecular cloud. Therefore we expect that they should possess the same bulk metallicities. Furthermore, both stars also host giant planets on eccentric orbits with pericenters ≲0.2 AU. Here, we investigate if planets with such orbits could lead to the host stars ingesting material, which in turn may leave similar chemical imprints in their atmospheric abundances. We derived abundances of 15 elements spanning a range of condensation temperature, T {sub C} ≈ 40-1660 K. The two stars are found to have a mean element-to-element abundance difference of 0.04 ± 0.07 dex, which is consistent with both stars having identical bulk metallicities. In addition, for both stars, the refractory elements (T {sub C} >900 K) exhibit a positive correlation between abundance (relative to solar) and T {sub C}, with similar slopes of ≈1×10{sup –4} dex K{sup –1}. The measured positive correlations are not perfect; both stars exhibit a scatter of ≈5×10{sup –5} dex K{sup –1} about the mean trend, and certain elements (Na, Al, Sc) are similarly deviant in both stars. These findings are discussed in the context of models for giant planet migration that predict the accretion of H-depleted rocky material by the host star. We show that a simple simulation of a solar-type star accreting material with Earth-like composition predicts a positive—but imperfect—correlation between refractory elemental abundances and T {sub C}. Our measured slopes are consistent with what is predicted for the ingestion of 10-20 Earths by each star in the system. In addition, the specific element-by-element scatter might be used to distinguish between planetary accretion and Galactic chemical evolution scenarios.

  6. THE UNUSUAL QUADRUPLE SYSTEM HD 91962 WITH A “PLANETARY” ARCHITECTURE

    Energy Technology Data Exchange (ETDEWEB)

    Tokovinin, Andrei [Cerro Tololo Inter-American Observatory, Casilla 603, La Serena (Chile); Latham, David W. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Mason, Brian D., E-mail: atokovinin@ctio.noao.edu, E-mail: dlatham@cfa.harvard.edu, E-mail: bdm@usno.navy.mil [U.S. Naval Observatory, 3450 Massachusetts Ave., Washington, DC (United States)

    2015-06-15

    The young nearby solar-type star HD 91962 is a rare quadruple system where three companions revolve around the main component with periods of 170.3 days, 8.85 years, and 205 years. The two outer orbits are nearly co-planar, and all orbits have small eccentricities. We refine the visual orbit of the outer pair and determine the combined spectro-interferometric orbit of the middle 8.8 year pair and the spectroscopic orbit of the inner binary. The middle and inner orbits are likely locked in a 1:19 resonance, and the ratio of the outer and middle periods is ∼23. The masses of all components are estimated (inside-out: 1.14, 0.32, 0.64, 0.64 solar mass).  The dynamical parallax is 27.4 ± 0.6 mas. We speculate that this multiple system originated from collapse of an isolated core and that the companions migrated in a dissipative disk. Other multiple systems with similar features (co-planarity, small eccentricity, and period ratio around 20) are known.

  7. HD 35502: a hierarchical triple system with a magnetic B5IVpe primary

    CERN Document Server

    Sikora, James; Bohlender, David; Shultz, Matt; Adelman, Saul; Alecian, Evelyne; Hanes, David; Monin, Dmitry; Neiner, Coralie; MiMeS, the

    2016-01-01

    We present our analysis of HD~35502 based on high- and medium-resolution spectropolarimetric observations. Our results indicate that the magnetic B5IVsnp star is the primary component of a spectroscopic triple system and that it has an effective temperature of $18.4\\pm0.6\\,{\\rm kK}$, a mass of $5.7\\pm0.6\\,M_\\odot$, and a polar radius of $3.0^{+1.1}_{-0.5}\\,R_\\odot$. The two secondary components are found to be essentially identical A-type stars for which we derive effective temperatures ($8.9\\pm0.3\\,{\\rm kK}$), masses ($2.1\\pm0.2\\,M_\\odot$), and radii ($2.1\\pm0.4\\,R_\\odot$). We infer a hierarchical orbital configuration for the system in which the secondary components form a tight binary with an orbital period of $5.66866(6)\\,{\\rm d}$ that orbits the primary component with a period of over $40\\,{\\rm yrs}$. Least-Squares Deconvolution (LSD) profiles reveal Zeeman signatures in Stokes $V$ indicative of a longitudinal magnetic field produced by the B star ranging from approximately $-4$ to $0\\,{\\rm kG}$ with a m...

  8. Debris disks in main sequence binary systems

    CERN Document Server

    Trilling, D E; Stapelfeldt, K R; Rieke, G H; Su, K Y L; Gray, R O; Corbally, C J; Bryden, G; Chen, C H; Boden, A; Beichman, C A

    2006-01-01

    We observed 69 A3-F8 main sequence binary star systems using the Multiband Imaging Photometer for Spitzer onboard the Spitzer Space Telescope. We find emission significantly in excess of predicted photospheric flux levels for 9(+4/-3)% and 40(+7/-6)% of these systems at 24 and 70 microns, respectively. Twenty two systems total have excess emission, including four systems that show excess emission at both wavelengths. A very large fraction (nearly 60%) of observed binary systems with small (<3 AU) separations have excess thermal mission. We interpret the observed infrared excesses as thermal emission from dust produced by collisions in planetesimal belts. The incidence of debris disks around main sequence A3-F8 binaries is marginally higher than that for single old AFGK stars. Whatever combination of nature (birth conditions of binary systems) and nurture (interactions between the two stars) drives the evolution of debris disks in binary systems, it is clear that planetesimal formation is not inhibited to a...

  9. The Magellan PFS Planet Search Program: Radial Velocity and Stellar Abundance Analyses of the 360 AU, Metal-Poor Binary "Twins" HD 133131A & B

    CERN Document Server

    Teske, Johanna K; Vogt, Steve S; Díaz, Matías; Butler, R Paul; Crane, Jeffrey D; Thompson, Ian B; Arriagada, Pamela

    2016-01-01

    We present a new precision radial velocity (RV) dataset that reveals multiple planets orbiting the stars in the $\\sim$360 AU, G2$+$G2 "twin" binary HD 133131AB. Our 6 years of high-resolution echelle observations from MIKE and 5 years from PFS on the Magellan telescopes indicate the presence of two eccentric planets around HD 133131A with minimum masses of 1.43$\\pm$0.03 and 0.63$\\pm$0.15 $\\mathcal{M}_{\\rm J}$ at 1.44$\\pm$0.005 and 4.79$\\pm$0.92 AU, respectively. Additional PFS observations of HD 133131B spanning 5 years indicate the presence of one eccentric planet of minimum mass 2.50$\\pm$0.05 $\\mathcal{M}_{\\rm J}$ at 6.40$\\pm$0.59 AU, making it one of the longest period planets detected with RV to date. These planets are the first to be reported primarily based on data taken with PFS on Magellan, demonstrating the instrument's precision and the advantage of long-baseline RV observations. We perform a differential analysis between the Sun and each star, and between the stars themselves, to derive stellar par...

  10. The Magellan PFS Planet Search Program: Radial Velocity and Stellar Abundance Analyses of the 360 au, Metal-poor Binary “Twins” HD 133131A & B

    Science.gov (United States)

    Teske, Johanna K.; Shectman, Stephen A.; Vogt, Steve S.; Díaz, Matías; Butler, R. Paul; Crane, Jeffrey D.; Thompson, Ian B.; Arriagada, Pamela

    2016-12-01

    We present a new precision radial velocity (RV) data set that reveals multiple planets orbiting the stars in the ˜360 au, G2+G2 “twin” binary HD 133131AB. Our six years of high-resolution echelle observations from MIKE and five years from the Planet Finder Spectrograph (PFS) on the Magellan telescopes indicate the presence of two eccentric planets around HD 133131A with minimum masses of 1.43 ± 0.03 and 0.63 ± 0.15 {{ M }}{{J}} at 1.44 ± 0.005 and 4.79 ± 0.92 au, respectively. Additional PFS observations of HD 133131B spanning five years indicate the presence of one eccentric planet of minimum mass 2.50 ± 0.05 {{ M }}{{J}} at 6.40 ± 0.59 au, making it one of the longest-period planets detected with RV to date. These planets are the first to be reported primarily based on data taken with the PFS on Magellan, demonstrating the instrument’s precision and the advantage of long-baseline RV observations. We perform a differential analysis between the Sun and each star, and between the stars themselves, to derive stellar parameters and measure a suite of 21 abundances across a wide range of condensation temperatures. The host stars are old (likely ˜9.5 Gyr) and metal-poor ([Fe/H] ˜ -0.30), and we detect a ˜0.03 dex depletion in refractory elements in HD 133131A versus B (with standard errors ˜0.017). This detection and analysis adds to a small but growing sample of binary “twin” exoplanet host stars with precise abundances measured, and represents the most metal-poor and likely oldest in that sample. Overall, the planets around HD 133131A and B fall in an unexpected regime in planet mass-host star metallicity space and will serve as an important benchmark for the study of long-period giant planets. This paper includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile.

  11. Stacking Analysis of Binary Systems with HAWC

    Science.gov (United States)

    Brisbois, Chad; HAWC Collaboration

    2017-01-01

    Detecting binary systems at TeV energies is an important problem because only a handful of such systems are currently known. The nature of such systems is typically thought to be composed of a compact object and a massive star. The TeV emission from these systems does not obviously correspond to emission in GeV or X-ray, where many binary systems have previously been found. This study focuses on a stacking method to detect TeV emission from LS 5039, a known TeV binary, to test its efficacy in HAWC data. Stacking is a widely employed method for increasing signal to noise ratio in optical astronomy, but has never been attempted previously with HAWC. HAWC is an ideal instrument to search for TeV binaries, because of its wide field of view and high uptime. Applying this method to the entire sky may allow HAWC to detect binary sources of very short or very long periods not sensitive to current analyses. NSF, DOE, Los Alamos, Michigan Tech, CONACyt, UNAM, BUAP.

  12. Stability of multiplanet systems in binaries

    CERN Document Server

    Marzari, F

    2016-01-01

    When exploring the stability of multiplanet systems in binaries, two parameters are normally exploited: the critical semimajor axis ac computed by Holman and Wiegert (1999) within which planets are stable against the binary perturbations, and the Hill stability limit Delta determining the minimum separation beyond which two planets will avoid mutual close encounters. Our aim is to test whether these two parameters can be safely applied in multiplanet systems in binaries or if their predictions fail for particular binary orbital configurations. We have used the frequency map analysis (FMA) to measure the diffusion of orbits in the phase space as an indicator of chaotic behaviour. First we revisited the reliability of the empirical formula computing ac in the case of single planets in binaries and we find that, in some cases, it underestimates by 10-20% the real outer limit of stability. For two planet systems, the value of Delta is close to that computed for planets around single stars, but the level of chaoti...

  13. A Model for Contact Binary Systems

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A model for contact binary systems is presented, which incorporates the following special features: a) The energy exchange between the components is based on the understanding that the energy exchange is due to the release of potential, kinetic and thermal energies of the exchanged mass. b) A special form of mass and angular momentum loss occurring in contact binaries is losses via the outer Lagrangian point. c) The effects of spin, orbital rotation and tidal action on the stellar structure as well as the effect of meridian circulation on the mixing of the chemical elements are considered. d) The model is valid not only for low-mass contact binaries but also for high-mass contact binaries. For illustration, we used the model to trace the evolution of a massive binary system consisting of one 12M⊙ and one 5M⊙ star. The result shows that the start and end of the contact stage fall within the semi-detached phase during which the primary continually transfers mass to the secondary. The time span of the contact stage is short and the mass transfer rate is very large. Therefore, the contact stage can be regarded as a special part of the semi-detached phase with a large mass transfer rate. Both mass loss through the outer Lagrangian point and oscillation between contact and semi-contact states can occur during the contact phase, and the effective temperatures of the primary and the secondary are almost equal.

  14. HD 35502: a hierarchical triple system with a magnetic B5IVpe primary

    Science.gov (United States)

    Sikora, J.; Wade, G. A.; Bohlender, D. A.; Shultz, M.; Adelman, S. J.; Alecian, E.; Hanes, D.; Monin, D.; Neiner, C.; MiMeS Collaboration; BinaMIcS Collaboration

    2016-08-01

    We present our analysis of HD 35502 based on high- and medium-resolution spectropolarimetric observations. Our results indicate that the magnetic B5IVsnp star is the primary component of a spectroscopic triple system and that it has an effective temperature of 18.4 ± 0.6 kK, a mass of 5.7 ± 0.6 M⊙, and a polar radius of 3.0^{+1.1}_{-0.5} R_{odot }. The two secondary components are found to be essentially identical A-type stars for which we derive effective temperatures (8.9 ± 0.3 kK), masses (2.1 ± 0.2 M⊙), and radii (2.1 ± 0.4 R⊙). We infer a hierarchical orbital configuration for the system in which the secondary components form a tight binary with an orbital period of 5.668 66(6) d that orbits the primary component with a period of over 40 yr. Least-Squares Deconvolution profiles reveal Zeeman signatures in Stokes V indicative of a longitudinal magnetic field produced by the B star ranging from approximately -4 to 0 kG with a median uncertainty of 0.4 kG. These measurements, along with the line variability produced by strong emission in Hα, are used to derive a rotational period of 0.853 807(3) d. We find that the measured v sin i = 75 ± 5 km s-1 of the B star then implies an inclination angle of the star's rotation axis to the line of sight of 24^{+6}_{-10}{}^circ. Assuming the Oblique Rotator Model, we derive the magnetic field strength of the B star's dipolar component (14^{+9}_{-3} kG) and its obliquity (63± 13deg). Furthermore, we demonstrate that the calculated Alfvén radius (41^{+17}_{-6}R_ast) and Kepler radius (2.1^{+0.4}_{-0.7}R_ast) place HD 35502's central B star well within the regime of centrifugal magnetosphere-hosting stars.

  15. DIRECT IMAGING OF AN ASYMMETRIC DEBRIS DISK IN THE HD 106906 PLANETARY SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Kalas, Paul G.; Wang, Jason J.; Duchene, Gaspard; Dong, Ruobing; Graham, James R.; Rosa, Robert J. De [Astronomy Department, University of California, Berkeley CA 94720-3411 (United States); Rajan, Abhijith; Patience, Jennifer [School of Earth and Space Exploration, Arizona State University, P.O. Box 871404, Tempe, AZ 85287 (United States); Millar-Blanchaer, Maxwell A.; Chilcote, Jeffrey [Department of Astronomy and Astrophysics, University of Toronto, Toronto ON M5S 3H4 (Canada); Chen, Christine [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Fitzgerald, Michael P. [Department of Physics and Astronomy, UCLA, Los Angeles, CA 90095 (United States); Macintosh, Bruce [Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Stanford, CA 94305 (United States); Murray-Clay, Ruth [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Matthews, Brenda; Marois, Christian; Draper, Zachary H.; Lawler, Samantha [National Research Council of Canada Herzberg, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Rameau, Julien; Doyon, René [Institut de Recherche sur les Exoplanetes, Département de Physique, Université de Montréal, Montréal QC H3C 3J7 (Canada); and others

    2015-11-20

    We present the first scattered light detections of the HD 106906 debris disk using the Gemini/Gemini Planet Imager in the infrared and Hubble Space Telescope (HST)/Advanced Camera for Surveys in the optical. HD 106906 is a 13 Myr old F5V star in the Sco–Cen association, with a previously detected planet-mass candidate HD 106906b projected 650 AU from the host star. Our observations reveal a near edge-on debris disk that has a central cleared region with radius ∼50 AU, and an outer extent >500 AU. The HST data show that the outer regions are highly asymmetric, resembling the “needle” morphology seen for the HD 15115 debris disk. The planet candidate is oriented ∼21° away from the position angle of the primary’s debris disk, strongly suggesting non-coplanarity with the system. We hypothesize that HD 106906b could be dynamically involved in the perturbation of the primary’s disk, and investigate whether or not there is evidence for a circumplanetary dust disk or cloud that is either primordial or captured from the primary. We show that both the existing optical properties and near-infrared colors of HD 106906b are weakly consistent with this possibility, motivating future work to test for the observational signatures of dust surrounding the planet.

  16. VLSI binary multiplier using residue number systems

    Energy Technology Data Exchange (ETDEWEB)

    Barsi, F.; Di Cola, A.

    1982-01-01

    The idea of performing multiplication of n-bit binary numbers using a hardware based on residue number systems is considered. This paper develops the design of a VLSI chip deriving area and time upper bounds of a n-bit multiplier. To perform multiplication using residue arithmetic, numbers are converted from binary to residue representation and, after residue multiplication, the result is reconverted to the original notation. It is shown that the proposed design requires an area a=o(n/sup 2/ log n) and an execution time t=o(log/sup 2/n). 7 references.

  17. Stellar Companions to the Exoplanet Host Stars HD 2638 and HD 164509

    Science.gov (United States)

    Wittrock, Justin M.; Kane, Stephen R.; Horch, Elliott P.; Hirsch, Lea; Howell, Steve B.; Ciardi, David R.; Everett, Mark E.; Teske, Johanna K.

    2016-11-01

    An important aspect of searching for exoplanets is understanding the binarity of the host stars. It is particularly important, because nearly half of the solar-like stars within our own Milky Way are part of binary or multiple systems. Moreover, the presence of two or more stars within a system can place further constraints on planetary formation, evolution, and orbital dynamics. As part of our survey of almost a hundred host stars, we obtained images at 692 and 880 nm bands using the Differential Speckle Survey Instrument (DSSI) at the Gemini-North Observatory. From our survey, we detect stellar companions to HD 2638 and HD 164509. The stellar companion to HD 2638 has been previously detected, but the companion to HD 164509 is a newly discovered companion. The angular separation for HD 2638 is 0.512 ± 0.″002 and for HD 164509 is 0.697+/- 0\\buildrel{\\prime\\prime}\\over{.} 002. This corresponds to a projected separation of 25.6 ± 1.9 au and 36.5 ± 1.9 au, respectively. By employing stellar isochrone models, we estimate the mass of the stellar companions of HD 2638 and HD 164509 to be 0.483 ± 0.007 M ⊙ and 0.416+/- 0.007 {M}⊙ , respectively, and their effective temperatures to be 3570 ± 8 K and 3450 ± 7 K, respectively. These results are consistent with the detected companions being late-type M dwarfs.

  18. BROWN DWARF BINARIES FROM DISINTEGRATING TRIPLE SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Reipurth, Bo [Institute for Astronomy and NASA Astrobiology Institute University of Hawaii, 640 N. Aohoku Place, Hilo, HI 96720 (United States); Mikkola, Seppo, E-mail: reipurth@ifa.hawaii.edu, E-mail: Seppo.Mikkola@utu.fi [Tuorla Observatory, University of Turku, Väisäläntie 20, Piikkiö (Finland)

    2015-04-15

    Binaries in which both components are brown dwarfs (BDs) are being discovered at an increasing rate, and their properties may hold clues to their origin. We have carried out 200,000 N-body simulations of three identical stellar embryos with masses drawn from a Chabrier IMF and embedded in a molecular core. The bodies are initially non-hierarchical and undergo chaotic motions within the cloud core, while accreting using Bondi–Hoyle accretion. The coupling of dynamics and accretion often leads to one or two dominant bodies controlling the center of the cloud core, while banishing the other(s) to the lower-density outskirts, leading to stunted growth. Eventually each system transforms either to a bound hierarchical configuration or breaks apart into separate single and binary components. The orbital motion is followed for 100 Myr. In order to illustrate 200,000 end-states of such dynamical evolution with accretion, we introduce the “triple diagnostic diagram,” which plots two dimensionless numbers against each other, representing the binary mass ratio and the mass ratio of the third body to the total system mass. Numerous freefloating BD binaries are formed in these simulations, and statistical properties are derived. The separation distribution function is in good correspondence with observations, showing a steep rise at close separations, peaking around 13 AU and declining more gently, reaching zero at separations greater than 200 AU. Unresolved BD triple systems may appear as wider BD binaries. Mass ratios are strongly peaked toward unity, as observed, but this is partially due to the initial assumptions. Eccentricities gradually increase toward higher values, due to the lack of viscous interactions in the simulations, which would both shrink the orbits and decrease their eccentricities. Most newborn triple systems are unstable and while there are 9209 ejected BD binaries at 1 Myr, corresponding to about 4% of the 200,000 simulations, this number has grown to

  19. Planet formation in slightly inclined binary systems

    Directory of Open Access Journals (Sweden)

    Ge J.

    2011-07-01

    Full Text Available One of the major problems of planet formation in close binary systems, such as α Centauri AB, is the formation of planetary embryos or cores by mutual accretion of km-sized planetesimals. In this contribution, we test the planetesimal accretion in such close binary systems but with small inclinations iB = 0.1–10° between the binary orbital plane and the gas disk plane. Compared to previous studies (coplanar case with iB = 0, we find that (1 planetesimal disk is stratified in the vertical direction and planetesimals are redistributed on different orbit groups with respect to their sizes, thus (2 collisions between similar-sized bodies dominate, leading to low dV and favoring planetesimal accretion (3 the planetesimal collision timescale at 1–2 AU is estimated as: T ∼ (1 + 100iB × 103 yrs, where 0 ≤ iB ≤ 10°. As a conclusion, although planetesimal accretion are much more favored in slightly inclined binary systems, it is significantly less efficient and slowed-down as compared to the single-star case.

  20. The SOPHIE search for northern extrasolar planets. II. A multiple planet system around HD 9446

    Science.gov (United States)

    Hébrard, G.; Bonfils, X.; Ségransan, D.; Moutou, C.; Delfosse, X.; Bouchy, F.; Boisse, I.; Arnold, L.; Desort, M.; Díaz, R. F.; Eggenberger, A.; Ehrenreich, D.; Forveille, T.; Lagrange, A.-M.; Lovis, C.; Pepe, F.; Perrier, C.; Pont, F.; Queloz, D.; Santos, N. C.; Udry, S.; Vidal-Madjar, A.

    2010-04-01

    We report the discovery of a planetary system around HD 9446, performed from radial velocity measurements secured with the spectrograph SOPHIE at the 193-cm telescope of the Haute-Provence Observatory for more than two years. At least two planets orbit this G5V, active star: HD 9446b has a minimum mass of 0.7 MJup and a slightly eccentric orbit with a period of 30 days, whereas HD 9446c has a minimum mass of 1.8 MJup and a circular orbit with a period of 193 days. As for most of the known multiple planet systems, the HD 9446-system presents a hierarchical disposition with a massive outer planet and a lighter inner planet. Based on observations collected with the SOPHIE spectrograph on the 1.93-m telescope at Observatoire de Haute-Provence (CNRS), France, by the SOPHIE Consortium (program 07A.PNP.CONS). The full version of Table 1 (SOPHIE measurements of HD 9446) is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/513/A69

  1. BINARY NONLINEARIZATION FOR THE DIRAC SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    MAWENXIU

    1997-01-01

    A Bargmann symmetry constraint is proposed for the Lax pairs and the adjoint Lax pairs of the Dirac systems. It is shown that the spatial part of the nonlinearized Lax pairs and adjoint Lax pairs is a finite dimensional Linuville integrable Hamiltonian system and that under the control of the spatial part, the time parts of the nonlinearized Lax pairs and adjoint Lax pairs are interpreted as a hierarchy of commutative, finite dimensional Linuville integrable Hamiltoian systems whose Hamiltonian functions consist of a series of integrals of motion for the spatial part. Moreover an invaiutive representation of solutions of the Dirac systems exhibits their integrability by quadratures. This kind of symmetry constraint procedure involving thespectral problem and the adjoint spectral problem is referred to as a binary nonlinearization technique like a binary Darhoux transformation.

  2. Dynamics and Habitability in Binary Star Systems

    CERN Document Server

    Eggl, Siegfried; Pilat-Lohinger, Elke

    2014-01-01

    Determining planetary habitability is a complex matter, as the interplay between a planet's physical and atmospheric properties with stellar insolation has to be studied in a self consistent manner. Standardized atmospheric models for Earth-like planets exist and are commonly accepted as a reference for estimates of Habitable Zones. In order to define Habitable Zone boundaries, circular orbital configurations around main sequence stars are generally assumed. In gravitationally interacting multibody systems, such as double stars, however, planetary orbits are forcibly becoming non circular with time. Especially in binary star systems even relatively small changes in a planet's orbit can have a large impact on habitability. Hence, we argue that a minimum model for calculating Habitable Zones in binary star systems has to include dynamical interactions.

  3. Constraints on the architecture of the HD 95086 planetary system with the Gemini Planet Imager

    CERN Document Server

    Rameau, Julien; De Rosa, Robert J; Blunt, Sarah C; Patience, Jenny; Doyon, Rene; Graham, James R; Lafreniere, David; Macintosh, Bruce; Marchis, Franck; Bailey, Vanessa; Chilcote, Jeffrey K; Duchesse, Gaspard; Esposito, Thomas M; Hung, Li-Wei; Konopacky, Quinn M; Maire, Jerome; Marois, Christian; Metchev, Stanimir; Perrin, Marshall D; Pueyo, Laurent; Rajan, Abhijith; Savransky, Dmitry; Wang, Jason J; Ward-Duong, Kimberly; Wolff, Schuyler G; Ammons, S Mark; Hibon, Pascale; Ingraham, Patrick; Kalas, Paul; Morzinski, Katie M; Oppenheimer, Rebecca; Rantakyearo, Fredrik T; Thomas, Sandrine

    2016-01-01

    We present astrometric monitoring of the young exoplanet HD 95086 b obtained with the Gemini Planet Imager between 2013 and 2016. A small but significant position angle change is detected at constant separation; the orbital motion is confirmed with literature measurements. Efficient Monte Carlo techniques place preliminary constraints on the orbital parameters of HD 95086 b. With 68% confidence, a semimajor axis of 61.7^{+20.7}_{-8.4} au and an inclination of 153.0^{+9.7}_{-13.5} deg are favored, with eccentricity less than 0.21. Under the assumption of a co-planar planet-disk system, the periastron of HD 95086 b is beyond 51 au with 68% confidence. Therefore HD 95086 b cannot carve the entire gap inferred from the measured infrared excess in the SED of HD 95086. We use our sensitivity to additional planets to discuss specific scenarios presented in the literature to explain the geometry of the debris belts. We suggest that either two planets on moderately eccentric orbits or three to four planets with inhomo...

  4. Direct imaging of an asymmetric debris disk in the HD 106906 planetary system

    CERN Document Server

    Kalas, Paul G; Wang, Jason J; Millar-Blanchaer, Maxwell A; Duchene, Gaspard; Chen, Christine; Fitzgerald, Michael P; Dong, Ruobing; Graham, James R; Patience, Jennifer; Macintosh, Bruce; Murray-Clay, Ruth; Matthews, Brenda; Rameau, Julien; Marois, Christian; Chilcote, Jeffrey; De Rosa, Robert J; Doyon, René; Draper, Zachary H; Lawler, Samantha; Ammons, S Mark; Arriaga, Pauline; Bulger, Joanna; Cotten, Tara; Follette, Katherine B; Goodsell, Stephen; Greenbaum, Alexandra; Hibon, Pascale; Hinkley, Sasha; Hung, Li-Wei; Ingraham, Patrick; Konapacky, Quinn; Lafreniere, David; Larkin, James E; Long, Douglas; Maire, Jérôme; Marchis, Franck; Metchev, Stan; Morzinski, Katie M; Nielsen, Eric L; Oppenheimer, Rebecca; Perrin, Marshall D; Pueyo, Laurent; Rantakyrö, Fredrik T; Ruffio, Jean-Baptiste; Saddlemyer, Leslie; Savransky, Dmitry; Schneider, Adam C; Sivaramakrishnan, Anand; Soummer, Rémi; Song, Inseok; Thomas, Sandrine; Vasisht, Gautam; Ward-Duong, Kimberly; Wiktorowicz, Sloane J; Wolff, Schuyler G

    2015-01-01

    We present the first scattered light detections of the HD 106906 debris disk using Gemini/GPI in the infrared and HST/ACS in the optical. HD 106906 is a 13 Myr old F5V star in the Sco-Cen association, with a previously detected planet-mass candidate HD 106906b projected 650 AU from the host star. Our observations reveal a near edge-on debris disk that has a central cleared region with radius $\\sim$50 AU, and an outer extent $>$500 AU. The HST data show the outer regions are highly asymmetric, resembling the ''needle'' morphology seen for the HD 15115 debris disk. The planet candidate is oriented $\\sim$21$\\deg$ away from the position angle of the primary's debris disk, strongly suggesting non-coplanarity with the system. We hypothesize that HD 106906b could be dynamically involved in the perturbation of the primary's disk, and investigate whether or not there is evidence for a circumplanetary dust disk or cloud that is either primordial or captured from the primary. We show that both the existing optical prope...

  5. CALCULATING THE HABITABLE ZONE OF BINARY STAR SYSTEMS. II. P-TYPE BINARIES

    Energy Technology Data Exchange (ETDEWEB)

    Haghighipour, Nader [Institute for Astronomy and NASA Astrobiology Institute, University of Hawaii-Manoa, Honolulu, HI 96822 (United States); Kaltenegger, Lisa [MPIA, Koenigstuhl 17, Heidelberg, D-69117 (Germany)

    2013-11-10

    We have developed a comprehensive methodology for calculating the circumbinary habitable zone (HZ) in planet-hosting P-type binary star systems. We present a general formalism for determining the contribution of each star of the binary to the total flux received at the top of the atmosphere of an Earth-like planet and use the Sun's HZ to calculate the inner and outer boundaries of the HZ around a binary star system. We apply our calculations to the Kepler's currently known circumbinary planetary systems and show the combined stellar flux that determines the boundaries of their HZs. We also show that the HZ in P-type systems is dynamic and, depending on the luminosity of the binary stars, their spectral types, and the binary eccentricity, its boundaries vary as the stars of the binary undergo their orbital motion. We present the details of our calculations and discuss the implications of the results.

  6. Coalescence of Magnetized Binary Neutron Star Systems

    Science.gov (United States)

    Motl, Patrick M.; Anderson, Matthew; Lehner, Luis; Liebling, Steven L.; Neilsen, David; Palenzuela, Carlos; Ponce, Marcelo

    2015-01-01

    We present simulations of the merger of binary neutron star systems calculated with full general relativity and incorporating the global magnetic field structure for the stars evolved with resistive magnetohydrodynamics. Our simulation tools have recently been improved to incorporate the effects of neutrino cooling and have been generalized to allow for tabular equations of state to describe the degenerate matter. Of particular interest are possible electromagnetic counterparts to the gravitational radiation that emerges from these systems. We focus on magnetospheric interactions that ultimately tap into the gravitational potential energy of the binary to power a Poynting flux and deposition of energy through Joule heating and magnetic reconnection. We gratefully acknowledge the support of NASA through the Astrophysics Theory Program grant NNX13AH01G.

  7. Complex Binary Number System Algorithms and Circuits

    CERN Document Server

    Jamil, Tariq

    2013-01-01

    This book is a compilation of the entire research work on the topic of Complex Binary Number System (CBNS) carried out by the author as the principal investigator and members of his research groups at various universities during the years 1992-2012. Pursuant to these efforts spanning several years, the realization of CBNS as a viable alternative to represent complex numbers in an 'all-in-one' binary number format has become possible and efforts are underway to build computer hardware based on this unique number system. It is hoped that this work will be of interest to anyone involved in computer arithmetic and digital logic design and kindle renewed enthusiasm among the engineers working in the areas of digital signal and image processing for developing newer and efficient algorithms and techniques incorporating CBNS.

  8. Magellan AO System $z'$, $Y_S$, and $L'$ Observations of the Very Wide 650 AU HD 106906 Planetary System

    CERN Document Server

    Wu, Ya-Lin; Bailey, Vanessa P; Rodigas, Timothy J; Males, Jared R; Morzinski, Katie M; Follette, Katherine B; Hinz, Philip M; Puglisi, Alfio; Briguglio, Runa; Xompero, Marco

    2016-01-01

    We analyze archival data from Bailey and co-workers from the $Magellan$ adaptive optics system and present the first 0.9 $\\mu$m detection ($z' = 20.3\\pm0.4$ mag; $\\Delta z'=13.0\\pm0.4$ mag) of the 11 $M_\\mathrm{Jup}$ circumbinary planet HD 106906AB b, as well as the 1 and 3.8 $\\mu$m detections of the debris disk around the binary. The disk has an east-west asymmetry in length and surface brightness, especially at 3.8 $\\mu$m where the disk appears to be one-sided. The spectral energy distribution of b, when scaled to the $K_S$-band photometry, is consistent with 1800 K atmospheric models without significant dust reddening, unlike some young, very red, low-mass companions such as CT Cha B and 1RXS 1609 B. Therefore, the suggested circumplanetary disk of Kalas and co-workers might not contain much material, or might be closer to face-on. Finally, we suggest that the widest ($a\\gtrsim100$ AU) low mass ratio ($M_\\mathrm{p}/M_\\mathrm{\\star} \\equiv q\\lesssim0.01$) companions may have formed inside protoplanetary dis...

  9. 76 FR 2277 - List of Approved Spent Fuel Storage Casks: NUHOMS® HD System Revision 1

    Science.gov (United States)

    2011-01-13

    ... NUCLEAR FUEL, HIGH-LEVEL RADIOACTIVE WASTE, AND REACTOR- RELATED GREATER THAN CLASS C WASTE 1. The... the NUHOMS HD Horizontal Modular Storage System for Irradiated Nuclear Fuel. ] Docket Number: 72-1030... From the Federal Register Online via the Government Publishing Office NUCLEAR...

  10. 75 FR 25120 - List of Approved Spent Fuel Storage Casks: NUHOMS® HD System Revision 1

    Science.gov (United States)

    2010-05-07

    ... STORAGE OF SPENT NUCLEAR FUEL, HIGH-LEVEL RADIOACTIVE WASTE, AND REACTOR- RELATED GREATER THAN CLASS C... Safety Analysis Report for the NUHOMS HD Horizontal Modular Storage System for Irradiated Nuclear Fuel...; #0; #0;#0;Federal Register / Vol. 75, No. 88 / Friday, May 7, 2010 / Proposed Rules#0;#0; ]...

  11. Stellivore extraterrestrials? Binary stars as living systems

    Science.gov (United States)

    Vidal, Clément

    2016-11-01

    We lack signs of extraterrestrial intelligence (ETI) despite decades of observation in the whole electromagnetic spectrum. Could evidence be buried in existing data? To recognize ETI, we first propose criteria discerning life from non-life based on thermodynamics and living systems theory. Then we extrapolate civilizational development to both external and internal growth. Taken together, these two trends lead to an argument that some existing binary stars might actually be ETI. Since these hypothetical beings feed actively on stars, we call them "stellivores". I present an independent thermodynamic argument for their existence, with a metabolic interpretation of interacting binary stars. The jury is still out, but the hypothesis is empirically testable with existing astrophysical data. article>

  12. Tidal heating in close binary stellar systems

    Energy Technology Data Exchange (ETDEWEB)

    Rieutord, M.; Bonazzola, S.

    1987-07-15

    Tidal heating of a low-mass star in a close binary system, resulting from the conjugate effect of angular momentum loss and tidal action, is investigated via detailed study of the flow inside the secondary. It is found in the case of cataclysmic binaries that viscous dissipation is at most 10/sup -3/ x the nuclear luminosity of the star. It is shown, however, that the dissipation is very sensitive to the turbulent viscosity in the envelope of the secondary. The case of very close pairs of white dwarfs is also considered. It is shown that such pairs, which are thought to be the progenitors of Type I Supernovae may dissipate a power as large as 10/sup 38/ erg s/sup -1/, provided that they reach synchronization; such a heating will strongly modify the conditions in which the nuclear explosion starts.

  13. Brown Dwarf Binaries from Disintegrating Triple Systems

    CERN Document Server

    Reipurth, Bo

    2015-01-01

    We have carried out 200,000 N-body simulations of three identical stellar embryos with masses from a Chabrier IMF and embedded in a molecular core. The bodies are initially non-hierarchical and undergo chaotic motions, while accreting using Bondi-Hoyle accretion. The coupling of dynamics and accretion often leads to one or two dominant bodies controlling the center of the cloud core, while banishing the other(s) to the lower-density outskirts, leading to stunted growth. Eventually each system transforms either to a bound hierarchical configuration or breaks apart into separate single and binary components. The orbital motion is followed for 100 Myr. To illustrate the simulations we introduce the 'triple diagnostic diagram', which plots two dimensionless numbers against each other, representing the binary mass ratio and the mass ratio of the third body to the total system mass. Numerous freefloating BD binaries are formed in these simulations. The separation distribution function is in good correspondence with...

  14. Searching for Gas Giant Planets on Solar System Scales: VLT NACO/APP Observations of the Debris Disk Host Stars HD172555 and HD115892

    CERN Document Server

    Quanz, Sascha P; Meyer, Michael R; Girard, Julien H V; Kasper, Markus

    2011-01-01

    Using the APP coronagraph of VLT/NACO we searched for planetary mass companions around HD115892 and HD172555 in the thermal infrared at 4 micron. Both objects harbor unusually luminous debris disks for their age and it has been suggested that small dust grains were produced recently in transient events (e.g., a collision) in these systems. Such a collision of planetesimals or protoplanets could have been dynamically triggered by yet unseen companions. We did not detect any companions in our images but derived the following detection limits: For both objects we would have detected companions with apparent magnitudes between ~13.2-14.1 mag at angular separations between 0.4- 1.0" at the 5-sigma level. For HD115892 we were sensitive to companions with 12.1 mag even at 0.3". Using theoretical models these magnitudes are converted into mass limits. For HD115892 we would have detected objects with 10-15 M_Jup at angular separations between 0.4-1.0" (7-18 AU). At 0.3" (~5.5 AU) the detection limit was ~25 M_Jup. For...

  15. New spectroscopic binary companions of giant stars and updated metallicity distribution for binary systems

    CERN Document Server

    Bluhm, P; Vanzi, L; Soto, M G; Vos, J; Wittenmyer, R A; Olivares, F; Drass, H; Mennickent, R E; Vuckovic, M; Rojo, P; Melo, C H F

    2016-01-01

    We report the discovery of 24 spectroscopic binary companions to giant stars. We fully constrain the orbital solution for 6 of these systems. We cannot unambiguously derive the orbital elements for the remaining stars because the phase coverage is incomplete. Of these stars, 6 present radial velocity trends that are compatible with long-period brown dwarf companions.The orbital solutions of the 24 binary systems indicate that these giant binary systems have a wide range in orbital periods, eccentricities, and companion masses. For the binaries with restricted orbital solutions, we find a range of orbital periods of between $\\sim$ 97-1600 days and eccentricities of between $\\sim$ 0.1-0.4. In addition, we studied the metallicity distribution of single and binary giant stars. We computed the metallicity of a total of 395 evolved stars, 59 of wich are in binary systems. We find a flat distribution for these binary stars and therefore conclude that stellar binary systems, and potentially brown dwarfs, have a diffe...

  16. On the stability of the detected planet in the triple system HD 131399

    Science.gov (United States)

    Funk, B.; Pilat-Lohinger, E.; Bazsó, Á.; Bancelin, D.

    2017-03-01

    Wagner et al. (2016) reported the discovery of a Jovian planet within a triple-star system by using direct imaging. In their paper they suspect the planet might be on an unstable orbit. Due to the discovery by direct imaging the orbital parameters of the system (distances and eccentricities) possess large uncertainties. Therefore in our work we tested different dynamical configurations to determine the stable regions in the system HD 131399 by varying the distances and the eccentricities of the stellar and the planetary components. Using different numerical methods we could show that stable regions remain for almost all possible orbital parameters. Additionally we also investigated the possible habitability of the system HD 131399.

  17. Planetesimal accretion in binary star systems

    CERN Document Server

    Marzari, Francesco; Scholl, Hans

    2007-01-01

    Numerical simulations of planetesimal accretion in circumprimary and circumbinary orbits are described. The secular perturbations by the com- panion star and gas drag are included in our models. We derive limits on the parameters of the binary system for which accretion and then planetary forma- tion are possible. In the circumbinary case we also outline the radial distance from the baricenter of the stars beyond which accumulation always occurs. Hy- drodynamical simulations are also presented to validate our N-body approach based on the axisymmetric approximation for the gas of the disk.

  18. Two New Spotted Variables-HD 191262 and HD 191011

    Science.gov (United States)

    Hall, Douglas S.; Henry, Gregory W.

    1992-11-01

    New 1988-1990 photometry in V and B with a 16 inch automatic telescope shows that both HD 191262, a previously known chromospherically active binary, and its comparison star HD 191011 are variable, with starspots judged to be the mechanism in both. In HD 191262 and 191011, respectively, spot rotation periods of 5d.4 coefficients of k=0.054 and 0.28 were estimated. HD 191011, shown to be a KS giant about 475 parsecs away, had eight different spots present during the 2.5 years of observation.

  19. Radio emission from RS CVn binary systems

    Energy Technology Data Exchange (ETDEWEB)

    Doiron, D.J.

    1984-01-01

    The RS CVn binary stellar systems UX Ari, HR 1099, AR Lac, HR 5110, II Peg, lambda And, and SZ Psc were investigated by use of radio interferometry during the period from July 1982 through August 1983. Interferometry took two forms: Very Large Array (VLA) observations and Very Long Baseline Interferometry (VLBI). The VLA observations determined the characteristic polarization and flux behavior of the centimeter wavelength radio emission. The observed spectral index was near zero during quiescent periods, rising to between 0.5 and 1.0 during active periods. No net linear polarization is observed to a limit of 1.7%. This is expected since the Faraday depth of thermal electrons deduced from x-ray observations is approx. 10/sup 5/. Circular polarization is observed to be less than 20% at all frequencies often with a helicity reversal between 1.6 GHz and 5 GHz. The VLBI observations have shown that the brightness temperatures are often T/sub B/ approx.> 10/sup 10/ /sup 0/K and size sources smaller than or comparable to the overall size of the binary system. These data are consistent with incoherent gyrosynchrotron emission from mildly relativistic electrons which are optically thick to their own radiation at 1.6 GHz and optically thin at 5 GHz and above. The spectral behavior suggests that the radio emission is due to a power-law distribution of electrons.

  20. Physical parameters of close binary systems: VI

    CERN Document Server

    Gazeas, K D; Zola, S; Kreiner, J M; Rucinski, S M

    2009-01-01

    New high-quality CCD photometric light curves for the W UMa-type systems V410 Aur, CK Boo, FP Boo, V921 Her, ET Leo, XZ Leo, V839 Oph, V2357 Oph, AQ Psc and VY Sex are presented. The new multicolor light curves, combined with the spectroscopic data recently obtained at David Dunlap Observatory, are analyzed with the Wilson-Devinney code to yield the physical parameters (masses, radii and luminosities) of the components. Our models for all ten systems resulted in a contact configuration. Four binaries (V921 Her, XZ Leo, V2357 Oph and VY Sex) have low, while two (V410 Aur and CK Boo) have high fill-out factors. FP Boo, ET Leo, V839 Oph and AQ Psc have medium values of the fill-out factor. Three of the systems (FP Boo, V921 Her and XZ Leo) have very bright primaries as a result of their high temperatures and large radii.

  1. Discovery and analysis of p-mode and g-mode oscillations in the A-type primary of the eccentric binary HD 209295

    CERN Document Server

    Handler, G; Shobbrook, R R; Koen, C; Bruch, A; Romero-Colmenero, E; Pamyatnykh, A A; Willems, B; Eyer, L; James, D J; Maas, T

    2002-01-01

    We have discovered both intermediate-order gravity mode and low-order pressure mode pulsation in the same star, HD 209295. It is therefore both a Gamma Doradus and a Delta Scuti star, which makes it the first pulsating star to be a member of two classes. The star is a single-lined spectroscopic binary with an orbital period of 3.10575 d and an eccentricity of 0.352. Weak pulsational signals are found in both the radial velocity and line-profile variations, allowing us to show that the two highest-amplitude Gamma Doradus pulsation modes are consistent with l=1 and |m|=1. In our 280 h of BVI multi-site photometry we detected ten frequencies in the light variations, one in the Delta Scuti regime and nine in the Gamma Doradus domain. Five of the Gamma Doradus frequencies are exact integer multiples of the orbital frequency. This observation leads us to suspect they are tidally excited. Results of theoretical modeling (stability analysis, tidal excitation) were consistent with the observations. We could not detect...

  2. The Herbig Ae SB2 system HD 104237

    Directory of Open Access Journals (Sweden)

    Cowley C. R.

    2014-01-01

    Full Text Available We present here the most recent abundance analysis of this Herbig Ae system based on high-resolution UVES and HARPS spectra and the results of our magnetic field measurements using high-resolution spectra obtained with HARPSpol.

  3. Spectral modelling of massive binary systems

    CERN Document Server

    Palate, Matthieu; Koenigsberger, Gloria; Moreno, Edmundo

    2013-01-01

    Aims: We simulate the spectra of massive binaries at different phases of the orbital cycle, accounting for the gravitational influence of the companion star on the shape and physical properties of the stellar surface. Methods: We used the Roche potential modified to account for radiation pressure to compute the stellar surface of close circular systems and we used the TIDES code for surface computation of eccentric systems. In both cases, we accounted for gravity darkening and mutual heating generated by irradiation to compute the surface temperature. We then interpolated NLTE plane-parallel atmosphere model spectra in a grid to obtain the local spectrum at each surface point. We finally summed all contributions, accounting for the Doppler shift, limb-darkening, and visibility to obtain the total synthetic spectrum. We computed different orbital phases and sets of physical and orbital parameters. Results: Our models predict line strength variations through the orbital cycle, but fail to completely reproduce t...

  4. Spectroscopic study of the long-period dust-producing WC7pd+O9 binary HD192641

    CERN Document Server

    Lefèvre, L; Lepine, S; Moffat, A F J; Acker, A; Harries, T J; Annuk, K; Bohlender, D A; Demers, H; Grosdidier, Y; Hill, G M; Morrison, N D; Knauth, D C; Skalkowski, G; Viti, S

    2005-01-01

    We present the results of an optical spectroscopic study of the massive Wolf-Rayet binary WR137. These data cover the dust-formation maximum in 1997. Combining all available measurements of radial velocities, we derive, for the first time, a spectroscopic orbit with period 13.05 +/- 0.18 years. The resulting masses, adopting i=67degrees, are M(O)= 20 +/- 2 Mo and M(WR)= 4.4+/- 1.5 Mo. These appear, respectively, around normal and on the low side for the given spectral types. Analysis of the intense multi-site spectroscopic monitoring in 1999 shows that the CIII5696 and CIV5802/12 lines have the highest intrinsic variability levels. The periodogram analysis yields a small-amplitude modulation in the absorption troughs of the CIV5802/12 and HeI5876 lines with a period of 0.83 days, which could be related either to pulsations or large-scale rotating structures as seen in the WN4 star EZ Canis Majoris (WR6).Wavelet analysis of the strong emission lines of CIII5696 and CIV5802/12 enabled us to isolate and follow f...

  5. Stellar Companions to the Exoplanet Host Stars HD 2638 and HD 164509

    CERN Document Server

    Wittrock, Justin M; Horch, Elliott P; Hirsch, Lea; Howell, Steve B; Ciardi, David R; Everett, Mark E; Teske, Johanna K

    2016-01-01

    An important aspect of searching for exoplanets is understanding the binarity of the host stars. It is particularly important because nearly half of the solar-like stars within our own Milky Way are part of binary or multiple systems. Moreover, the presence of two or more stars within a system can place further constraints on planetary formation, evolution, and orbital dynamics. As part of our survey of almost a hundred host stars, we obtained images at 692 nm and 880 nm bands using the Differential Speckle Survey Instrument (DSSI) at the Gemini-North Observatory. From our survey, we detect stellar companions to HD 2638 and HD 164509. The stellar companion to HD 2638 has been previously detected, but the companion to HD 164509 is a newly discovered companion. The angular separation for HD 2638 is $0.512 \\pm 0.002\\arcsec$ and for HD 164509 is $0.697 \\pm 0.002\\arcsec$. This corresponds to a projected separation of $25.6 \\pm 1.9$ AU and $36.5 \\pm 1.9$ AU, respectively. By employing stellar isochrone models, we e...

  6. Host Star Properties and Transit Exclusion for the HD 38529 Planetary System

    CERN Document Server

    Henry, Gregory W; Wang, Sharon X; Wright, Jason T; Boyajian, Tabetha S; von Braun, Kaspar; Ciardi, David R; Dragomir, Diana; Farrington, Chris; Fischer, Debra A; Hinkel, Natalie R; Howard, Andrew W; Jensen, Eric; Laughlin, Gregory; Mahadevan, Suvrath; Pilyavsky, Genady

    2013-01-01

    The transit signature of exoplanets provides an avenue through which characterization of exoplanetary properties may be undertaken, such as studies of mean density, structure, and atmospheric composition. The Transit Ephemeris Refinement and Monitoring Survey (TERMS) is a program to expand the catalog of transiting planets around bright host stars by refining the orbits of known planets discovered with the radial velocity technique. Here we present results for the HD 38529 system. We determine fundamental properties of the host star through direct interferometric measurements of the radius and through spectroscopic analysis. We provide new radial velocity measurements that are used to improve the Keplerian solution for the two known planets, and we find no evidence for a previously postulated third planet. We also present 12 years of precision robotic photometry of HD 38529 that demonstrate the inner planet does not transit and the host star exhibits cyclic variations in seasonal mean brightness with a timesc...

  7. Milankovitch Cycles of Terrestrial Planets in Binary Star Systems

    CERN Document Server

    Forgan, Duncan H

    2016-01-01

    The habitability of planets in binary star systems depends not only on the radiation environment created by the two stars, but also on the perturbations to planetary orbits and rotation produced by the gravitational field of the binary and neighbouring planets. Habitable planets in binaries may therefore experience significant perturbations in orbit and spin. The direct effects of orbital resonances and secular evolution on the climate of binary planets remain largely unconsidered. We present latitudinal energy balance modelling of exoplanet climates with direct coupling to an N Body integrator and an obliquity evolution model. This allows us to simultaneously investigate the thermal and dynamical evolution of planets orbiting binary stars, and discover gravito-climatic oscillations on dynamical and secular timescales. We investigate the Kepler-47 and Alpha Centauri systems as archetypes of P and S type binary systems respectively. In the first case, Earthlike planets would experience rapid Milankovitch cycle...

  8. Optical and ultraviolet spectroscopy of three F + B binary stars

    Science.gov (United States)

    Bopp, Bernard W.; Dempsey, Robert C.; Parsons, Sidney B.

    1991-01-01

    Optical and ultraviolet spectroscopy is presented for three F + B objects that are members of the first group of strongly interacting, F II + B systems. The data obtained confirm that HD 59771, HD 242257, and CoD -30 5135 are all binary star systems consisting of a luminous F-type component and a B star. Strong, variable H-alpha emission is seen in all the stars. It is found that the UV spectrum of HD 59771 resembles the spectrum of HD 207739. CoD -30 5135 has the most dramatic mid-UV spectrum seen among the scores of observed cool + hot star systems.

  9. The Evolution of Compact Binary Star Systems

    Directory of Open Access Journals (Sweden)

    Yungelson, Lev R.

    2006-12-01

    Full Text Available We review the formation and evolution of compact binary stars consisting of white dwarfs (WDs, neutron stars (NSs, and black holes (BHs. Binary NSs and BHs are thought to be the primary astrophysical sources of gravitational waves (GWs within the frequency band of ground-based detectors, while compact binaries of WDs are important sources of GWs at lower frequencies to be covered by space interferometers (LISA. Major uncertainties in the current understanding of properties of NSs and BHs most relevant to the GW studies are discussed, including the treatment of the natal kicks which compact stellar remnants acquire during the core collapse of massive stars and the common envelope phase of binary evolution. We discuss the coalescence rates of binary NSs and BHs and prospects for their detections, the formation and evolution of binary WDs and their observational manifestations. Special attention is given to AM CVn-stars -- compact binaries in which the Roche lobe is filled by another WD or a low-mass partially degenerate helium-star, as these stars are thought to be the best LISA verification binary GW sources.

  10. New Pleiades Eclipsing Binaries and a Hyades Transiting System Identified by K2

    CERN Document Server

    David, Trevor J; Hillenbrand, Lynne A; Stassun, Keivan G; Stauffer, John; Rebull, Luisa M; Cody, Ann Marie; Isaacson, Howard; Howard, Andrew W; Aigrain, Suzanne

    2016-01-01

    We present the discovery in Kepler's $K2$ mission observations and our follow-up radial velocity observations from Keck/HIRES for four eclipsing binary (EB) star systems in the young benchmark Pleiades cluster. Based on our modeling results, we announce two new low mass ($M_{tot} < 0.6 M_\\odot$) EBs among Pleiades members (HCG 76 and MHO 9) and we report on two previously known Pleiades binaries that are also found to be EB systems (HII 2407 and HD 23642). We measured the masses of the binary HCG 76 to $\\lesssim$2.5% precision, and the radii to $\\lesssim$4.5% precision, which together with the precise effective temperatures yield an independent Pleiades distance of 132$\\pm$5 pc. We discuss another EB towards the Pleiades that is a possible but unlikely Pleiades cluster member (AK II 465). The two new confirmed Pleiades systems extend the mass range of Pleiades EB components to 0.2-2 $M_\\odot$. Our initial measurements of the fundamental stellar parameters for the Pleiades EBs are discussed in the context o...

  11. XZ And a semidetached asynchronous binary system

    Science.gov (United States)

    Manzoori, Davood

    2016-05-01

    In this work the light curves (LCs) solutions along with the radial velocity curve of the semidetached binary systemXZ And are presented using the PHOEBE program(ver 0.31a). Absolute parameters of the stellar components were then determined, enabling us to discuss structure and evolutionary status of the system. The analysis indicates that the primary is a non-synchronous (i.e., F1 = 3.50 ± 0.01) Main Sequence (MS) star and the secondary is a bit more evolved, and fills its Roche critical surface. In addition, times of minima data (" O - C curve") were analyzed. Apart from an almost parabolic variation in the general trend of O - C data, which was attributed to a mass transfer from the secondary with the rate ˙2 = (9.52 ± 0.41) × 10-10 M ⊙ yr-1; two cyclic variations with mean periods of 34.8 ± 2.4 and 23.3 ± 3.0 yr, modulating the orbital period, were found, which were attributed to a third body orbiting around the system, and magnetic activity cycle effect, respectively.

  12. Long-Term Stability of Planets in Binary Systems

    CERN Document Server

    Holman, M; Holman, Matthew; Wiegert, Paul

    1999-01-01

    A simple question of celestial mechanics is investigated: in what regions of phase space near a binary system can planets persist for long times? The planets are taken to be test particles moving in the field of an eccentric binary system. A range of values of the binary eccentricity and mass ratio is studied, and both the case of planets orbiting close to one of the stars, and that of planets outside the binary orbiting the system's center of mass, are examined. From the results, empirical expressions are developed for both 1) the largest orbit around each of the stars, and 2) the smallest orbit around the binary system as a whole, in which test particles survive the length of the integration (10^4 binary periods). The empirical expressions developed, which are roughly linear in both the mass ratio mu and the binary eccentricity e, are determined for the range 0.0 <= e <= 0.7-0.8 and 0.1 <= mu <= 0.9 in both regions, and can be used to guide searches for planets in binary systems. After consideri...

  13. Formation and Evolution of Binary Systems Containing Collapsed Stars

    Science.gov (United States)

    Rappaport, Saul; West, Donald (Technical Monitor)

    2003-01-01

    This research includes theoretical studies of the formation and evolution of five types of interacting binary systems. Our main focus has been on developing a number of comprehensive population synthesis codes to study the following types of binary systems: (i) cataclysmic variables (#3, #8, #12, #15), (ii) low- and intermediate-mass X-ray binaries (#13, #20, #21), (iii) high-mass X-ray binaries (#14, #17, #22), (iv) recycled binary millisecond pulsars in globular clusters (#5, #10, #ll), and (v) planetary nebulae which form in interacting binaries (#6, #9). The numbers in parentheses refer to papers published or in preparation that are listed in this paper. These codes take a new unified approach to population synthesis studies. The first step involves a Monte Carlo selection of the primordial binaries, including the constituent masses, and orbital separations and eccentricities. Next, a variety of analytic methods are used to evolve the primary star to the point where either a dynamical episode of mass transfer to the secondary occurs (the common envelope phase), or the system evolves down an alternate path. If the residual core of the primary is greater than 2.5 solar mass, it will evolve to Fe core collapse and the production of a neutron star and a supernova explosion. In the case of systems involving neutron stars, a kick velocity is chosen randomly from an appropriate distribution and added to the orbital dynamics which determine the state of the binary system after the supernova explosion. In the third step, all binaries which commence stable mass transfer from the donor star (the original secondary in the binary system) to the compact object, are followed with a detailed binary evolution code. Finally, we include all the relevant dynamics of the binary system. For example, in the case of LMXBs, the binary system, with its recoil velocity from the supernova explosion, is followed in time through its path in the Galactic potential. For our globular cluster

  14. Progenitor models of Wolf-Rayet+O binary systems

    NARCIS (Netherlands)

    Petrovic, J.; Langer, N.

    2007-01-01

    Since close WR+O binaries are the result of a strong interaction of both stars in massive close binary systems, they can be used to constrain the highly uncertain mass and angular momentum budget during the major mass- transfer phase. We explore the progenitor evolution of the three best suited WR+O

  15. Searching for Pulsars in Close Binary Systems

    CERN Document Server

    Jouteux, S; Stappers, B W; Jonker, P; Van der Klis, M

    2001-01-01

    We present a detailed mathematical analysis of the Fourier response of binary pulsar signals whose frequencies are modulated by circular orbital motion. The fluctuation power spectrum of such signals is found to be \

  16. MOST discovers a multimode delta Scuti star in a triple system: HD 61199

    CERN Document Server

    Hareter, M; Lehmann, H; Tsymbal, V; Hüber, D; Lenz, P; Weiss, W W; Matthews, J M; Rucinski, S; Rowe, J F; Kuschnig, R; Günther, D B; Moffat, A F J; Sasselov, D; Walker, G A H; Scholtz, A

    2008-01-01

    A field star, HD 61199 (V ~ 8), simultaneously observed with Procyon by the MOST (Microvariability & Oscillations of STars) satellite in continuous runs of 34, 17, and 34 days in 2004, 2005, and 2007, was found to pulsate in 11 frequencies in the delta Scuti range with amplitudes from 1.7 down to 0.09 mmag. The photometry also showed variations with a period of about four days. To investigate the nature of the longer period, 45 days of time-resolved spectroscopy was obtained at the Thueringer Landessternwarte Tautenburg in 2004. The radial velocity measurements indicate that HD 61199 is a triple system. A delta Scuti pulsator with a rich eigenspectrum in a multiple system is promising for asteroseismology. Our objectives were to identify which of the stars in the system is the delta Scuti variable and to obtain the orbital elements of the system and the fundamental parameters of the individual components, which are constrained by the pulsation frequencies of the delta Scuti star. Classical Fourier techniq...

  17. Resonances Required: Dynamical Analysis of the 24 Sex and HD 200964 Planetary Systems

    CERN Document Server

    Wittenmyer, Robert A; Tinney, C G

    2012-01-01

    We perform several suites of highly detailed dynamical simulations to investigate the architectures of the 24 Sextantis and HD 200964 planetary systems. The best fit orbital solution for the two planets in the 24 Sex system places them on orbits with periods that lie very close to 2:1 commensurability, while that for the HD 200964 system places the two planets therein in orbits whose periods lie close to a 4:3 commensurability. In both cases, the proposed best-fit orbits are mutually crossing - a scenario that is only dynamically feasible if the planets are protected from close encounters by the effects of mutual mean motion resonance. Our simulations reveal that the best fit orbits for both systems lie within narrow islands of dynamical stability, and are surrounded by much larger regions of extreme instability. As such, we show that the planets are only feasible if they are currently trapped in mutual mean-motion resonance - the 2:1 resonance in the case of 24 Sex b and c, and the 4:3 resonance in the case ...

  18. An extreme planetary system around HD219828. One long-period super Jupiter to a hot-neptune host star

    CERN Document Server

    Santos, N C; Faria, J P; Rey, J; Correia, A C M; Laskar, J; Udry, S; Adibekyan, V; Bouchy, F; Delgado-Mena, E; Melo, C; Dumusque, X; Hébrard, G; Lovis, C; Mayor, M; Montalto, M; Mortier, A; Pepe, F; Figueira, P; Sahlmann, J; Ségransan, D; Sousa, S G

    2016-01-01

    With about 2000 extrasolar planets confirmed, the results show that planetary systems have a whole range of unexpected properties. We present a full investigation of the HD219828 system, a bright metal-rich star for which a hot neptune has previously been detected. We used a set of HARPS, SOPHIE, and ELODIE radial velocities to search for the existence of orbiting companions to HD219828. A dynamical analysis is also performed to study the stability of the system and to constrain the orbital parameters and planet masses. We announce the discovery of a long period (P=13.1years) massive (msini=15.1MJup) companion (HD219828c) in a very eccentric orbit (e=0.81). The same data confirms the existence of a hot-neptune, HD219828b, with a minimum mass of 21 MEarth and a period of 3.83days. The dynamical analysis shows that the system is stable. The HD219828 system is extreme and unique in several aspects. First, among all known exoplanet systems it presents an unusually high mass ratio. We also show that systems like H...

  19. B fields in OB stars (BOB): The magnetic triple stellar system HD 164492C in the Trifid nebula

    Science.gov (United States)

    González, J. F.; Hubrig, S.; Przybilla, N.; Carroll, T.; Nieva, M.-F.; Ilyin, I.; Järvinen, S.; Morel, T.; Schöller, M.; Castro, N.; Barbá, R.; de Koter, A.; Schneider, F. R. N.; Kholtygin, A.; Butler, K.; Veramendi, M. E.; Langer, N.; BOB Collaboration

    2017-01-01

    HD 164492C is a spectroscopic triple stellar system that has been recently detected to possess a strong magnetic field. We have obtained high-resolution spectroscopic and spectropolarimetric observations over a timespan of two years and derived physical, chemical, and magnetic properties for this object. The system is formed by an eccentric close spectroscopic binary (Ca1-Ca2) with a period of 12.5 days, and a massive tertiary Cb. We calculated the orbital parameters of the close pair, reconstructed the spectra of the three components, and determined atmospheric parameters and chemical abundances by spectral synthesis. From spectropolarimetric observations, multi-epoch measurements of the longitudinal magnetic fields were obtained. The magnetic field is strongly variable on timescales of a few days, with a most probable period in the range of 1.4-1.6 days. Star Cb with Teff ˜ 25 000 K is the apparently fastest rotator and the most massive star of this triple system and has anomalous chemical abundances with a marked overabundance of helium, 0.35±0.04 by number. We identified this star as being responsible for the observed magnetic field, although the presence of magnetic fields in the components of the Ca pair cannot be excluded. Star Ca1 with a temperature of about 24 000 K presents a normal chemical pattern, while the least massive star Ca2 is a mid-B type star (Teff ˜ 15 000 K) with an overabundance of silicon. The obtained stellar parameters of the system components suggest a distance of 1.5 kpc and an age of 10-15 Myr.

  20. Circumstellar multi-planetary systems in binary stars: secular resonances and a semi-analytical approach to determine the location

    CERN Document Server

    Pilat-Lohinger, Elke; Funk, Barbara

    2016-01-01

    Binary stars are of special interest for studies of planetary motion and habitability as most of the stars in the solar neighborhood are part of such stellar systems. Since a secondary star causes gravitational perturbations the planetary motion is restricted to certain regions of the phase space depending on the binary configuration. In case a binary system hosts a giant planet it is obvious that additional perturbations will occur. These perturbations will be studied in detail in this investigation where we take into account various binary-planet configurations. We show how the dynamics of another test-planet is influenced by mean motion and secular resonances. Therefore, it is important to know the locations of these resonances. First, we study the binary system HD41004AB to visualize the perturbations on the dynamics of test-planets caused by the secondary star and the detected giant planet. Then we perform a frequency analysis of the orbits to identify of the secular resonance. And finally, we develop a ...

  1. Fuzzy rank functions in the set of all binary systems.

    Science.gov (United States)

    Kim, Hee Sik; Neggers, J; So, Keum Sook

    2016-01-01

    In this paper, we introduce fuzzy rank functions for groupoids, and we investigate their roles in the semigroup of binary systems by using the notions of right parallelisms and [Formula: see text]-shrinking groupoids.

  2. KOI-3278: A Self-Lensing Binary Star System

    CERN Document Server

    Kruse, Ethan

    2014-01-01

    Over 40% of Sun-like stars are bound in binary or multistar systems. Stellar remnants in edge-on binary systems can gravitationally magnify their companions, as predicted 40 years ago. By using data from the Kepler spacecraft, we report the detection of such a "self-lensing" system, in which a 5-hour pulse of 0.1% amplitude occurs every orbital period. The white dwarf stellar remnant and its Sun-like companion orbit one another every 88.18 days, a long period for a white dwarf-eclipsing binary. By modeling the pulse as gravitational magnification (microlensing) along with Kepler's laws and stellar models, we constrain the mass of the white dwarf to be ~63% of the mass of our Sun. Further study of this system, and any others discovered like it, will help to constrain the physics of white dwarfs and binary star evolution.

  3. Iterative Solution for Systems of Nonlinear Two Binary Operator Equations

    Institute of Scientific and Technical Information of China (English)

    ZHANGZhi-hong; LIWen-feng

    2004-01-01

    Using the cone and partial ordering theory and mixed monotone operator theory, the existence and uniqueness of solutions for some classes of systems of nonlinear two binary operator equations in a Banach space with a partial ordering are discussed. And the error estimates that the iterative sequences converge to solutions are also given. Some relevant results of solvability of two binary operator equations and systems of operator equations are imnroved and generalized.

  4. A Detailed Analysis of the HD 73526 2:1 Resonant Planetary System

    CERN Document Server

    Wittenmyer, Robert A; Lee, Man Hoi; Horner, Jonathan; Tinney, C G; Butler, R P; Salter, G S; Carter, B D; Jones, H R A; O'Toole, S J; Bailey, J; Wright, D; Crane, J D; Schectman, S A; Arriagada, P; Thompson, I; Minniti, D; Diaz, M

    2013-01-01

    We present six years of new radial-velocity data from the Anglo-Australian and Magellan Telescopes on the HD 73526 2:1 resonant planetary system. We investigate both Keplerian and dynamical (interacting) fits to these data, yielding four possible configurations for the system. The new data now show that both resonance angles are librating, with amplitudes of 40 degrees and 60 degrees, respectively. We then perform long-term dynamical stability tests to differentiate these solutions, which only differ significantly in the masses of the planets. We show that while there is no clearly preferred system inclination, the dynamical fit with i=90 degrees provides the best combination of goodness-of-fit and long-term dynamical stability.

  5. A detailed analysis of the HD 73526 2:1 resonant planetary system

    Energy Technology Data Exchange (ETDEWEB)

    Wittenmyer, Robert A.; Horner, Jonathan; Tinney, C. G.; Salter, G. S.; Bailey, J.; Wright, D. [School of Physics, University of New South Wales, Sydney 2052 (Australia); Tan, Xianyu; Lee, Man Hoi [Department of Earth Sciences, The University of Hong Kong, Pokfulam Road (Hong Kong); Butler, R. P.; Arriagada, P. [Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road, NW, Washington, DC 20015-1305 (United States); Carter, B. D. [Faculty of Sciences, University of Southern Queensland, Toowoomba, Queensland 4350 (Australia); Jones, H. R. A. [University of Hertfordshire, Centre for Astrophysics Research, Science and Technology Research Institute, College Lane, AL10 9AB, Hatfield (United Kingdom); O' Toole, S. J. [Australian Astronomical Observatory, PO Box 915, North Ryde, NSW 1670 (Australia); Crane, J. D.; Schectman, S. A.; Thompson, I. [The Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Minniti, D.; Diaz, M., E-mail: rob@phys.unsw.edu.au [Institute of Astrophysics, Pontificia Universidad Catolica de Chile, Casilla 306, Santiago 22 (Chile)

    2014-01-10

    We present six years of new radial velocity data from the Anglo-Australian and Magellan Telescopes on the HD 73526 2:1 resonant planetary system. We investigate both Keplerian and dynamical (interacting) fits to these data, yielding four possible configurations for the system. The new data now show that both resonance angles are librating, with amplitudes of 40° and 60°, respectively. We then perform long-term dynamical stability tests to differentiate these solutions, which only differ significantly in the masses of the planets. We show that while there is no clearly preferred system inclination, the dynamical fit with i = 90° provides the best combination of goodness-of-fit and long-term dynamical stability.

  6. Relating binary-star planetary systems to central configurations

    CERN Document Server

    Veras, Dimitri

    2016-01-01

    Binary-star exoplanetary systems are now known to be common, for both wide and close binaries. However, their orbital evolution is generally unsolvable. Special cases of the N-body problem which are in fact completely solvable include dynamical architectures known as central configurations. Here, I utilize recent advances in our knowledge of central configurations to assess the plausibility of linking them to coplanar exoplanetary binary systems. By simply restricting constituent masses to be within stellar or substellar ranges characteristic of planetary systems, I find that (i) this constraint reduces by over 90 per cent the phase space in which central configurations may occur, (ii) both equal-mass and unequal-mass binary stars admit central configurations, (iii) these configurations effectively represent different geometrical extensions of the Sun-Jupiter-Trojan-like architecture, (iv) deviations from these geometries are no greater than ten degrees, and (v) the deviation increases as the substellar masse...

  7. KIC 7177553: A QUADRUPLE SYSTEM OF TWO CLOSE BINARIES

    Energy Technology Data Exchange (ETDEWEB)

    Lehmann, H. [Thüringer Landessternwarte Tautenburg, Sternwarte 5, D-07778 Tautenburg (Germany); Borkovits, T. [Baja Astronomical Observatory of Szeged University, H-6500 Baja, Szegedi út, Kt. 766 (Hungary); Rappaport, S. A. [Massachusetts Institute of Technology, Department of Physics, 77 Massachusetts Avenue, Cambridge, MA 02139-4307 (United States); Ngo, H. [California Institute of Technology, Division of Geological and Planetary Sciences, 1200 E. California Boulevard, MC 150-21, Pasadena, CA 91125 (United States); Mawet, D. [California Institute of Technology, Astronomy Dept. MC 249-17, 1200 E. California Boulevard, Pasadena, CA 91125 (United States); Csizmadia, Sz. [German Aerospace Center (DLR), Institut für Planeten-forschung, Rutherfordstraße 2, D-12489 Berlin (Germany); Forgács-Dajka, E., E-mail: lehm@tls-tautenburg.de, E-mail: borko@electra.bajaobs.hu, E-mail: sar@mit.edu, E-mail: hngo@caltech.edu, E-mail: dmawet@astro.caltech.edu, E-mail: szilard.csizmadia@dlr.de, E-mail: e.forgacs-dajka@astro.elte.hu [Astronomical Department, Eötvös University, H-1118 Budapest, Pázmány Péter stny. 1/A (Hungary)

    2016-03-01

    KIC 7177553 was observed by the Kepler satellite to be an eclipsing eccentric binary star system with an 18-day orbital period. Recently, an eclipse timing study of the Kepler binaries has revealed eclipse timing variations (ETVs) in this object with an amplitude of ∼100 s and an outer period of 529 days. The implied mass of the third body is that of a super-Jupiter, but below the mass of a brown dwarf. We therefore embarked on a radial velocity (RV) study of this binary to determine its system configuration and to check the hypothesis that it hosts a giant planet. From the RV measurements, it became immediately obvious that the same Kepler target contains another eccentric binary, this one with a 16.5-day orbital period. Direct imaging using adaptive optics reveals that the two binaries are separated by 0.″4 (∼167 AU) and have nearly the same magnitude (to within 2%). The close angular proximity of the two binaries and very similar γ velocities strongly suggest that KIC 7177553 is one of the rare SB4 systems consisting of two eccentric binaries where at least one system is eclipsing. Both systems consist of slowly rotating, nonevolved, solar-like stars of comparable masses. From the orbital separation and the small difference in γ velocity, we infer that the period of the outer orbit most likely lies in the range of 1000–3000 yr. New images taken over the next few years, as well as the high-precision astrometry of the Gaia satellite mission, will allow us to set much narrower constraints on the system geometry. Finally, we note that the observed ETVs in the Kepler data cannot be produced by the second binary. Further spectroscopic observations on a longer timescale will be required to prove the existence of the massive planet.

  8. The missing Wolf-Rayet X-ray binary systems

    Science.gov (United States)

    Munoz, M.; Moffat, A. F. J.; Hill, G. M.; Richardson, N. D.; Pablo, H.

    We investigate the rarity of the Wolf-Rayet X-ray binaries (WRXRBs) in contrast to their predecessors, the high mass X-ray binaries (HMXRBs). Recent studies suggest that common envelope (CE) mergers during the evolution of a HMXRBs may be responsible (Linden et al. 2012). We conduct a binary population synthesis to generate a population of HMXRBs mimicking the Galactic sample and vary the efficiency parameter during the CE phase to match the current WRXRB to HMXRB ratio. We find that ˜50% of systems must merge to match observational constraints.

  9. Milankovitch cycles of terrestrial planets in binary star systems

    Science.gov (United States)

    Forgan, Duncan

    2016-12-01

    The habitability of planets in binary star systems depends not only on the radiation environment created by the two stars, but also on the perturbations to planetary orbits and rotation produced by the gravitational field of the binary and neighbouring planets. Habitable planets in binaries may therefore experience significant perturbations in orbit and spin. The direct effects of orbital resonances and secular evolution on the climate of binary planets remain largely unconsidered. We present latitudinal energy balance modelling of exoplanet climates with direct coupling to an N-Body integrator and an obliquity evolution model. This allows us to simultaneously investigate the thermal and dynamical evolution of planets orbiting binary stars, and discover gravito-climatic oscillations on dynamical and secular time-scales. We investigate the Kepler-47 and Alpha Centauri systems as archetypes of P- and S-type binary systems, respectively. In the first case, Earth-like planets would experience rapid Milankovitch cycles (of order 1000 yr) in eccentricity, obliquity and precession, inducing temperature oscillations of similar periods (modulated by other planets in the system). These secular temperature variations have amplitudes similar to those induced on the much shorter time-scale of the binary period. In the Alpha Centauri system, the influence of the secondary produces eccentricity variations on 15 000 yr time-scales. This produces climate oscillations of similar strength to the variation on the orbital time-scale of the binary. Phase drifts between eccentricity and obliquity oscillations creates further cycles that are of order 100 000 yr in duration, which are further modulated by neighbouring planets.

  10. The Evolutionary Outcomes of Expansive Binary Asteroid Systems

    Science.gov (United States)

    McMahon, Jay W.

    2016-10-01

    Singly synchronous binary asteroid systems have several evolutionary end-states, which depend heavily on the BYORP effect. In the case of expansive BYORP, the binary system could evolve to become a wide asynchronous binary system (Jacobson, et al 2014), or the system could expand far enough to become disrupted to form a heliocentric pair (Vokrouhlicky et al 2008). Cuk et al (2011) found that upon expanding the secondary will quickly become asynchronous, and will end up re-establishing synchronous rotation with the opposite attitude, causing the binary orbit to subsequently contract. The distinction between these outcomes depends on whether the secondary asteroid stays synchronized, which keeps the BYORP effect active and the orbit expanding. As the orbit expands, the secondary libratation will expand, and the libration will also causes large variations in the binary orbit due to the elongation of the secondary. If the eccentricity and libration are bound to small enough values the system can expand significantly. This work discusses the stability of the libration and orbital motion as a binary expands from a wide variety of simulation runs with various parameters. We investigate how the strength of tides and BYORP change the stability of the librational motion; an important factor is the speed of BYORP expansion as slower expansion allows tides to have a more stabilizing effect. We also investigate the effect of heliocentric orbit semimajor axis and eccentricity. We find that resonances between the coupled orbit-libration frequencies and the heliocentric orbit cause instability in the binary orbit eccentricity which produces a strong preference for wide binary production, especially amongst retrograde binary systems. This instability also becomes stronger with large heliocentric eccentricities. Prograde binaries are more stable and can possible grow to become asteroid pairs. We find that even in the presence of tides, reestablishment of synchronous spin into a

  11. Spectral modelling of the Alpha Virginis (Spica) binary system

    CERN Document Server

    Palate, M; Rauw, G; Harrington, D; Moreno, E

    2013-01-01

    Context: The technique of matching synthetic spectra computed with theoretical stellar atmosphere models to the observations is widely used in deriving fundamental parameters of massive stars. When applied to binaries, however, these models generally neglect the interaction effects present in these systems Aims: The aim of this paper is to explore the uncertainties in binary stellar parameters that are derived from single-star models Methods: Synthetic spectra that include the tidal perturbations and irradiation effects are computed for the binary system alpha Virginis (Spica) using our recently-developed CoMBiSpeC model. The synthetic spectra are compared to S/N~2000 observations and optimum values of Teff and log(g) are derived. Results: The binary interactions have only a small effect on the strength of the photospheric absorption lines in Spica (<2% for the primary and <4% for the secondary). These differences are comparable to the uncertainties inherent to the process of matching synthetic spectra ...

  12. A quintuple star system containing two eclipsing binaries

    Science.gov (United States)

    Rappaport, S.; Lehmann, H.; Kalomeni, B.; Borkovits, T.; Latham, D.; Bieryla, A.; Ngo, H.; Mawet, D.; Howell, S.; Horch, E.; Jacobs, T. L.; LaCourse, D.; Sódor, Á.; Vanderburg, A.; Pavlovski, K.

    2016-10-01

    We present a quintuple star system that contains two eclipsing binaries. The unusual architecture includes two stellar images separated by 11 arcsec on the sky: EPIC 212651213 and EPIC 212651234. The more easterly image (212651213) actually hosts both eclipsing binaries which are resolved within that image at 0.09 arcsec, while the westerly image (212651234) appears to be single in adaptive optics (AO), speckle imaging, and radial velocity (RV) studies. The `A' binary is circular with a 5.1-d period, while the `B' binary is eccentric with a 13.1-d period. The γ velocities of the A and B binaries are different by ˜10 km s-1. That, coupled with their resolved projected separation of 0.09 arcsec, indicates that the orbital period and separation of the `C' binary (consisting of A orbiting B) are ≃65 yr and ≃25 au, respectively, under the simplifying assumption of a circular orbit. Motion within the C orbit should be discernible via future RV, AO, and speckle imaging studies within a couple of years. The C system (i.e. 212651213) has an RV and proper motion that differ from that of 212651234 by only ˜1.4 km s-1 and ˜3 mas yr-1. This set of similar space velocities in three dimensions strongly implies that these two objects are also physically bound, making this at least a quintuple star system.

  13. Stellar Activity and Exclusion of the Outer Planet in the HD 99492 System

    CERN Document Server

    Kane, Stephen R; Henry, Gregory W; Hinkel, Natalie R; Jensen, Eric L N; Boyajian, Tabetha S; Fischer, Debra A; Howard, Andrew W; Isaacson, Howard T; Wright, Jason T

    2016-01-01

    A historical problem for indirect exoplanet detection has been contending with the intrinsic variability of the host star. If the variability is periodic, it can easily mimic various exoplanet signatures, such as radial velocity variations that originate with the stellar surface rather than the presence of a planet. Here we present an update for the HD~99492 planetary system, using new radial velocity and photometric measurements from the Transit Ephemeris Refinement and Monitoring Survey (TERMS). Our extended time series and subsequent analyses of the Ca II H\\&K emission lines show that the host star has an activity cycle of $\\sim$13 years. The activity cycle correlates with the purported orbital period of the outer planet, the signature of which is thus likely due to the host star activity. We further include a revised Keplerian orbital solution for the remaining planet, along with a new transit ephemeris. Our transit-search observations were inconclusive.

  14. Design of multi-view stereoscopic HD video transmission system based on MPEG-21 digital item adaptation

    Science.gov (United States)

    Lee, Seokhee; Lee, Kiyoung; Kim, Man Bae; Kim, JongWon

    2005-11-01

    In this paper, we propose a design of multi-view stereoscopic HD video transmission system based on MPEG-21 Digital Item Adaptation (DIA). It focuses on the compatibility and scalability to meet various user preferences and terminal capabilities. There exist a large variety of multi-view 3D HD video types according to the methods for acquisition, display, and processing. By following the MPEG-21 DIA framework, the multi-view stereoscopic HD video is adapted according to user feedback. A user can be served multi-view stereoscopic video which corresponds with his or her preferences and terminal capabilities. In our preliminary prototype, we verify that the proposed design can support two deferent types of display device (stereoscopic and auto-stereoscopic) and switching viewpoints between two available viewpoints.

  15. Asteroseismology and forced oscillations of HD 209295, the first member of two classes of pulsating star

    CERN Document Server

    Handler, G; Shobbrook, R R; Koen, C; Bruch, A; Romero-Colmenero, E; Pamyatnykh, A A; Willems, B; Eyer, L; James, D J; Maas, T; Crause, L A

    2001-01-01

    We report the discovery of both intermediate-order gravity mode and low-order pressure mode pulsation in the same star, HD 209295. It is therefore both a gamma Doradus and a delta Scuti star, which makes it the first confirmed member of two classes of pulsating star. This object is located in a close binary system with an unknown, but likely degenerate companion in an eccentric orbit, and some of the gamma Doradus pulsation frequencies are exact integer multiples of the orbital frequency. We suggest that these pulsations are tidally excited. HD 209295 may be the progenitor of an intermediate-mass X-Ray binary.

  16. LS 5039 and HD 259440: A Multiwavelength Approach

    Science.gov (United States)

    Aragona, Christina

    2012-07-01

    A handful of Galactic High Mass X-ray Binaries have been observed to emit radiation at very high energies (MeV-TeV), dubbed gamma-ray binaries. This poster will review the importance of multiwavelength observations for understanding two of these systems, HD 259440 and LS 5039. For HD 259440, detection of a nearby high-energy source instigated optical observations to search for evidence the system's binarity. For LS 5039, optically determined orbital and stellar parameters combined with constraints on the system inclination angle from X-ray, UV, and radio observations are bringing us closer to identifying the nature of the interaction region and the compact object. I am grateful for support from NSF grant AST-1109247 and Lehigh University.

  17. A Quintuple Star System Containing Two Eclipsing Binaries

    CERN Document Server

    Rappaport, S; Kalomeni, B; Borkovits, T; Latham, D; Bieryla, A; Ngo, H; Mawet, D; Howell, S; Horch, E; Jacobs, T L; LaCourse, D; Sodor, A; Vanderburg, A; Pavlovski, K

    2016-01-01

    We present a quintuple star system that contains two eclipsing binaries. The unusual architecture includes two stellar images separated by 11" on the sky: EPIC 212651213 and EPIC 212651234. The more easterly image (212651213) actually hosts both eclipsing binaries which are resolved within that image at 0.09", while the westerly image (212651234) appears to be single in adaptive optics (AO), speckle imaging, and radial velocity (RV) studies. The 'A' binary is circular with a 5.1-day period, while the 'B' binary is eccentric with a 13.1-day period. The gamma velocities of the A and B binaries are different by ~10 km/s. That, coupled with their resolved projected separation of 0.09", indicates that the orbital period and separation of the 'C' binary (consisting of A orbiting B) are ~65 years and ~25 AU, respectively, under the simplifying assumption of a circular orbit. Motion within the C orbit should be discernible via future RV, AO, and speckle imaging studies within a couple of years. The C system (i.e., 21...

  18. KIC 7177553: a quadruple system of two close binaries

    CERN Document Server

    Lehmann, H; Rappaport, S A; Ngo, H; Mawet, D; Csizmadia, Sz; Forgacs-Dajka, E

    2016-01-01

    KIC 7177553 was observed by the Kepler satellite to be an eclipsing eccentric binary star system with an 18-day orbital period. Recently, an eclipse timing study of the Kepler binaries has revealed eclipse timing variations in this object with an amplitude of about 100 sec, and an outer period of 529 days. The implied mass of the third body is that of a superJupiter, but below the mass of a brown dwarf. We therefore embarked on a radial velocity study of this binary to determine its system configuration and to check the hypothesis that it hosts a giant planet. From the radial velocity measurements, it became immediately obvious that the same Kepler target contains another eccentric binary, this one with a 16.5-day orbital period. Direct imaging using adaptive optics reveals that the two binaries are separated by 0.4 arcsec (about 167 AU), and have nearly the same magnitude (to within 2%). The close angular proximity of the two binaries, and very similar Gamma velocities, strongly suggest that KIC 7177553 is o...

  19. Mass transfer in eccentric binary systems using the binary evolution code BINSTAR

    CERN Document Server

    Davis, P J; Deschamps, R

    2013-01-01

    We present the first calculations of mass transfer via RLOF for a binary system with a significant eccentricity using our new binary stellar evolution code. The study focuses on a 1.50+1.40 Msun main sequence binary with an eccentricity of 0.25, and an orbital period of about 0.7 d. The reaction of the stellar components due to mass transfer is analyzed, and the evolution of mass transfer during the periastron passage is compared to recent smooth particle hydrodynamics (SPH) simulations. The impact of asynchronism and non-zero eccentricity on the Roche lobe radius, and the effects of tidal and rotational deformation on the stars' structures, are also investigated. Calculations were performed using the state-of-the-art binary evolution code BINSTAR, which calculates simultaneously the structure of the two stars and the evolution of the orbital parameters. The evolution of the mass transfer rate during an orbit has a Gaussian-like shape, with a maximum at periastron, in qualitative agreement with SPH simulation...

  20. Relating binary-star planetary systems to central configurations

    Science.gov (United States)

    Veras, Dimitri

    2016-11-01

    Binary-star exoplanetary systems are now known to be common, for both wide and close binaries. However, their orbital evolution is generally unsolvable. Special cases of the N-body problem which are in fact completely solvable include dynamical architectures known as central configurations. Here, I utilize recent advances in our knowledge of central configurations to assess the plausibility of linking them to coplanar exoplanetary binary systems. By simply restricting constituent masses to be within stellar or substellar ranges characteristic of planetary systems, I find that (i) this constraint reduces by over 90 per cent the phase space in which central configurations may occur, (ii) both equal-mass and unequal-mass binary stars admit central configurations, (iii) these configurations effectively represent different geometrical extensions of the Sun-Jupiter-Trojan-like architecture, (iv) deviations from these geometries are no greater than 10°, and (v) the deviation increases as the substellar masses increase. This study may help restrict future stability analyses to architectures which resemble exoplanetary systems, and might hint at where observers may discover dust, asteroids and/or planets in binary-star systems.

  1. Stochastic Background of Gravitational Waves Generated by Compact Binary Systems

    CERN Document Server

    Evangelista, E F D

    2015-01-01

    Binary Systems are the most studied sources of gravitational waves. The mechanisms of emission and the behavior of the orbital parameters are well known and can be written in analytic form in several cases. Besides, the strongest indication of the existence of gravitational waves has arisen from the observation of binary systems. On the other hand, when the detection of gravitational radiation becomes a reality, one of the observed pattern of the signals will be probably of stochastic background nature, which are characterized by a superposition of signals emitted by many sources around the universe. Our aim here is to develop an alternative method of calculating such backgrounds emitted by cosmological compact binary systems during their periodic or quasiperiodic phases. We use an analogy with a problem of Statistical Mechanics in order to perform this sum as well as taking into account the temporal variation of the orbital parameters of the systems. Such a kind of background is of particular importance sinc...

  2. Understanding the evolution of close binary systems with radio pulsars

    CERN Document Server

    Benvenuto, O G; Horvath, J E

    2014-01-01

    We calculate the evolution of close binary systems (CBSs) formed by a neutron star (behaving as a radio pulsar) and a normal donor star, evolving either to helium white dwarf (HeWD) or ultra short orbital period systems. We consider X-ray irradiation feedback and evaporation due to radio pulsar irradiation. We show that irradiation feedback leads to cyclic mass transfer episodes, allowing CBSs to be observed in-between as binary radio pulsars under conditions in which standard, non-irradiated models predict the occurrence of a low mass X-ray binary. This behavior accounts for the existence of a family of eclipsing binary systems known as redbacks. We predict that redback companions should almost fill their Roche lobe, as observed in PSR J1723-2837. This state is also possible for systems evolving with larger orbital periods. Therefore, binary radio pulsars with companion star masses usually interpreted as larger than expected to produce HeWDs may also result in such {\\it quasi - Roche Lobe Overflow} states, r...

  3. Constraining the orbits of young binary systems with ALMA

    Science.gov (United States)

    Nogueira, Natasha; Jensen, Eric L. N.; Akeson, Rachel L.

    2017-01-01

    Measuring the orbits of young binary systems can provide the stars' individual stellar masses as well as insight into the dynamical effects they should have on each others' protoplanetary disks. As a byproduct of our ALMA observations of disks in young binary systems, we are able to measure precise relative separations of binaries with separations of 0.22--0.35 arcsec (~ 30--50 AU at the distance of the Taurus star-forming region). Most of these systems were first resolved in the early 1990s, so our epoch 2015 observations add an additional point in the orbit that is 20--25 years after the discovery epoch. While this coverage does not yet yield a definitive orbit, the extended coverage allows improved constraints on the binary orbital parameters. We present updated orbital constraints on a number of young binary systems, including XZ Tau, GH Tau, GN Tau, IS Tau, V955 Tau, and JH 112.This work makes use of the following ALMA data: ADS/JAO.ALMA#2011.0.00150.S. and ADS/JAO.ALMA#2013.1.00105.S. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada) and NSC and ASIAA (Taiwan), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

  4. Understanding Gravitational Waves from Inspiral Binary Systems and its Detection

    CERN Document Server

    Antelis, Javier M

    2016-01-01

    The discovery of the events GW150926 and GW151226 has experimentally confirmed the existence of gravitational waves (GW) and has demonstrated the existence of binary stellar-mass black hole systems. This finding marks the beginning of a new era that will reveal unexpected features of our universe. This work presents a basic insight to the fundamental theory of GW emitted by inspiral binary systems and describes the scientific and technological efforts developed to measure this waves using the interferometer-based detector called LIGO. Subsequently, the work proposes a comprehensive data analysis methodology based on the matched filter algorithm which aims to detect GW signals emitted by inspiral binary systems of astrophysical sources. The method is validated with freely available LIGO data which contain injected GW signals. Results of experiments performed to assess detection carried out show that the method was able to recover the 85% of the injected GW.

  5. Dynamical Formation of Close Binary Systems in Globular Clusters

    CERN Document Server

    Pooley, D; Anderson, S F; Baumgardt, H; Filippenko, A V; Gaensler, B M; Homer, L; Hut, P; Kaspi, V M; Margon, B; McMillan, S; Zwart, S P; Van der Klis, M; Verbunt, F

    2003-01-01

    We know from observations that globular clusters are very efficient catalysts in forming unusual short-period binary systems or their offspring, such as low-mass X-ray binaries (LMXBs; neutron stars accreting matter from low-mass stellar companions), cataclysmic variables (CVs; white dwarfs accreting matter from stellar companions), and millisecond pulsars (MSPs; rotating neutron stars with spin periods of a few ms). Although there has been little direct evidence, the overabundance of these objects in globular clusters has been attributed by numerous authors to the high densities in the cores, which leads to an increase in the formation rate of exotic binary systems through close stellar encounters. Many such close binary systems emit X-radiation at low luminosities (L_x < 10^{34} erg/s) and are being found in large numbers through observations with the Chandra X-ray Observatory. Here we present conclusive observational evidence for a link between the number of close binaries observed in X-rays in a globul...

  6. Physical parameters of components in close binary systems: V

    OpenAIRE

    Zola, S.; Kreiner, J. M.; Zakrzewski, B.; Kjurkchieva, D. P.; Marchev, D. V.; Baran, A.; Rucinski, S. M.; Ogloza, W.; Siwak, M.; Koziel, D.; Drozdz, M.; Pokrzywka, B.

    2009-01-01

    The paper presents combined spectroscopic and photometric orbital solutions for ten close binary systems: CN And, V776 Cas, FU Dra, UV Lyn, BB Peg, V592 Per, OU Ser, EQ Tau, HN UMa and HT Vir. The photometric data consist of new multicolor light curves, while the spectroscopy has been recently obtained within the radial velocity program at the David Dunlap Observatory (DDO). Absolute parameters of the components for these binary systems are derived. Our results confirm that CN And is not a co...

  7. Orbital Dynamics of Exoplanetary Systems Kepler-62, HD 200964 and Kepler-11

    CERN Document Server

    Mia, Rajib

    2016-01-01

    The presence of mean-motion resonances (MMR) in exoplanetary systems is a new exciting field of celestial mechanics which motivate us to consider the present work to study the dynamical behaviour of exoplanetary systems by time evolution of the orbital elements of the planets. Mainly we study the influence of planetary perturbations on semi-major axis and eccentricity. We identify $(r+1):r$ mean-motion resonance terms in the expression of disturbing function and obtain the perturbations from the truncated disturbing function. Using the expansion of the disturbing function of three body problem and an analytical approach, we solve the equations of motion. The solution which is obtained analytically is compared with that of obtained by numerical method to validate our analytical result. In the present work we consider three exoplanetary systems namely Kepler-62, HD 200964 and Kepler-11. We have plotted the evolution of the resonant angles and found that they librate around constant value. In view of this, our o...

  8. Looking for Super-Earths in the HD 189733 System: A Search for Transits in Most Space-Based Photometry

    CERN Document Server

    Croll, Bryce; Rowe, Jason F; Gladman, Brett; Miller-Ricci, Eliza; Sasselov, Dimitar; Walker, Gordon A H; Kuschnig, Rainer; Lin, Douglas N C; Guenther, David B; Moffat, Anthony F J; Rucinski, Slavek M; Weiss, Werner W

    2007-01-01

    We have made a comprehensive transit search for exoplanets down to ~1.5 - 2 Earth radii in the HD 189733 system, based on 21-days of nearly uninterrupted broadband optical photometry obtained with the MOST (Microvariability & Oscillations of STars) satellite in 2006. We have searched these data for realistic limb-darkened transits from exoplanets other than the known hot Jupiter, HD 189733b, with periods ranging from about 0.4 days to one week. Monte Carlo statistical tests of the data with synthetic transits inserted into the data-set allow us to rule out additional close-in exoplanets with sizes ranging from about 0.15 - 0.31 RJ (Jupiter radii), or 1.7 - 3.5 RE (Earth radii) on orbits whose planes are near that of HD 189733b. These null results constrain theories that invoke lower-mass hot Super-Earth and hot Neptune planets in orbits similar to HD 189733b due to the inward migration of this hot Jupiter. This work also illustrates the feasibility of discovering smaller transiting planets around chromosp...

  9. Looking for Giant Earths in the HD 209458 System: A Search for Transits in MOST Space-based Photometry

    CERN Document Server

    Croll, B; Rowe, J F; Kuschnig, R; Walker, A; Gladman, B; Sasselov, D; Cameron, C; Walker, G A H; Lin, D N C; Günther, D B; Moffat, A F J; Rucinski, S M; Weiss, W W; Croll, Bryce; Matthews, Jaymie M.; Rowe, Jason F.; Kuschnig, Rainer; Walker, Andrew; Gladman, Brett; Sasselov, Dimitar; Cameron, Chris; Walker, Gordon A. H.; Lin, Douglas N. C.; Guenther, David B.; Moffat, Anthony F. J.; Rucinski, Slavek M.; Weiss, Werner W.

    2007-01-01

    We have made a comprehensive transit search for exoplanets down to about 2 Earth radii in the HD 209458 system, based on nearly uninterrupted broadband optical photometry obtained with the MOST (Microvariability and Oscillations of Stars) satellite, spanning 14 days in 2004 and 44 days in 2005. We have searched these data for limb-darkened transits at periods other than that of the known giant planet, from about 0.5 days to 2 weeks. Monte Carlo statistical tests of the data with synthetic transits inserted allow us to rule out additional close-in exoplanets with sizes ranging from about 0.20-0.36 RJ (Jupiter radii), or 2.2-4.0 RE (Earth radii) on orbits whose planes are near that of HD 209458b. These null results constrain theories that invoke lower mass planets in orbits similar to HD 209458b to explain its anomalously large radius, and those that predict "hot Earths" due to the inward migration of HD 209458b.

  10. The Dynamical Origin of the Multi-Planetary System HD45364

    CERN Document Server

    Rein, Hanno; Kley, Wilhelm

    2009-01-01

    The recently discovered planetary system HD45364 which consists of a Jupiter and Saturn mass planet is very likely in a 3:2 mean motion resonance. The standard scenario to form planetary commensurabilities is convergent migration of two planets embedded in a protoplanetary disc. When the planets are initially separated by a period ratio larger than two, convergent migration will most likely lead to a very stable 2:1 resonance for moderate migration rates. To avoid this fate, formation of the planets close enough to prevent this resonance may be proposed. However, such a simultaneous formation of the planets within a small annulus, seems to be very unlikely. Rapid type III migration of the outer planet crossing the 2:1 resonance is one possible way around this problem. In this paper, we investigate this idea in detail. We present an estimate for the required convergent migration rate and confirm this with N-body and hydrodynamical simulations. If the dynamical history of the planetary system had a phase of rap...

  11. THE LICK-CARNEGIE SURVEY: A NEW TWO-PLANET SYSTEM AROUND THE STAR HD 207832

    Energy Technology Data Exchange (ETDEWEB)

    Haghighipour, Nader [Institute for Astronomy and NASA Astrobiology Institute, University of Hawaii-Manoa, Honolulu, HI 96822 (United States); Butler, R. Paul [Department of Terrestrial Magnetism, Carnegie Institute of Washington, Washington, DC 20015 (United States); Rivera, Eugenio J.; Vogt, Steven S. [UCO/Lick Observatory, Department of Astronomy and Astrophysics, University of California at Santa Cruz, Santa Cruz, CA 95064 (United States); Henry, Gregory W. [Center of Excellence in Information Systems, Tennessee State University, Nashville, TN 37209 (United States)

    2012-09-01

    Keck/HIRES precision radial velocities of HD 207832 indicate the presence of two Jovian-type planetary companions in Keplerian orbits around this G star. The planets have minimum masses of Msin i = 0.56 M{sub Jup} and 0.73 M{sub Jup}, with orbital periods of {approx}162 and {approx}1156 days, and eccentricities of 0.13 and 0.27, respectively. Stroemgren b and y photometry reveals a clear stellar rotation signature of the host star with a period of 17.8 days, well separated from the period of the radial velocity variations, reinforcing their Keplerian origin. The values of the semimajor axes of the planets suggest that these objects have migrated from the region of giant planet formation to closer orbits. In order to examine the possibility of the existence of additional (small) planets in the system, we studied the orbital stability of hypothetical terrestrial-sized objects in the region between the two planets and interior to the orbit of the inner body. Results indicated that stable orbits exist only in a small region interior to planet b. However, the current observational data offer no evidence for the existence of additional objects in this system.

  12. Radiation reaction in binary systems in general relativity

    Science.gov (United States)

    Kennefick, Daniel John

    1997-09-01

    This thesis is concerned with current problems in, and historical aspects of, the problem of radiation reaction in stellar binary systems in general relativity. Part I addresses current issues in the orbital evolution due to gravitational radiation damping of compact binaries. A particular focus is on the inspiral of small bodies orbiting large black holes, employing a perturbation formalism. In addition, the merger, at the end of the insprial, of comparable mass compact binaries, such as neutron star binaries is also discussed. The emphasis of Part I is on providing detailed descriptions of sources and signals with a view to optimising signal analysis in gravitational wave detectors, whether ground- or space- based interferometers, or resonant mass detectors. Part II of the thesis examines the historical controversies surrounding the problem of gravitational waves, and gravitational radiation damping in stellar binaries. In particular, it focuses on debates in the mid 20th-century on whether binary star systems would really exhibit this type of damping and emit gravitational waves, and on the 'quadrupole formula controversy' of the 1970s and 1980s, on the question whether the standard formular describing energy loss due to emission of gravitational waves was correctly derived for such systems. The study shed light on the role of analogy in science, especially where its use is controversial, on the importance of style in physics and on the problem of identity in science, as the use of history as a rhetorical device in controversial debate is examined. The concept of the Theoretician's Regress is introduced to explain the difficulty encountered by relativists in closing debate in this controversy, which persisted in one forms or another for several decades.

  13. Density-Driven segregation in Binary and Ternary Granular Systems

    NARCIS (Netherlands)

    Windows-Yule, Kit; Parker, David

    2015-01-01

    We present a first experimental study of density-induced segregation within a three-dimensional, vibrofluidised, ternary granular system. Using Positron Emission Particle Tracking (PEPT), we study the steady-state particle distributions achieved by binary and ternary granular beds under a variety of

  14. Supernovae in Binary Systems: An Application of Classical Mechanics.

    Science.gov (United States)

    Mitalas, R.

    1980-01-01

    Presents the supernova explosion in a binary system as an application of classical mechanics. This presentation is intended to illustrate the power of the equivalent one-body problem and provide undergraduate students with a variety of insights into elementary classical mechanics. (HM)

  15. The new Wolf-Rayet binary system WR62a

    Science.gov (United States)

    Collado, A.; Gamen, R.; Barbá, R. H.

    2013-04-01

    Context. A significant number of the Wolf-Rayet stars seem to be binary or multiple systems, but the nature of many of them is still unknown. Dedicated monitoring of WR stars favours the discovery of new systems. Aims: We explore the possibility that WR62a is a binary system. Methods: We analysed the spectra of WR62a, obtained between 2002 and 2010, to look for radial-velocity and spectral variations that would suggest there is a binary component. We searched for periodicities in the measured radial velocities and determined orbital solutions. A period search was also performed on the "All-Sky Automated Survey" photometry. Results: We find that WR62a is a double-lined spectroscopic binary with a WN5 primary star and an O 5.5-6 type secondary component in orbit with a period of 9.1447 d. The minimum masses range between 21 and 23 M⊙ for the WN star and between 39 and 42 M⊙ for the O-type star, thus indicating that the WN star is less massive than the O-type component. We detect a phase shift in the radial-velocity curve of the He ii λ4686 emission line relative to the other emission line curves. The equivalent width of this emission line shows a minimum value when the WN star passes in front of the system. The analysis of the ASAS photometry confirms the spectroscopic periodicity, presenting a minimum at the same phase.

  16. Nonparametric statistical structuring of knowledge systems using binary feature matches

    DEFF Research Database (Denmark)

    Mørup, Morten; Glückstad, Fumiko Kano; Herlau, Tue

    2014-01-01

    Structuring knowledge systems with binary features is often based on imposing a similarity measure and clustering objects according to this similarity. Unfortunately, such analyses can be heavily influenced by the choice of similarity measure. Furthermore, it is unclear at which level clusters ha...

  17. Estimation of the Ideal Binary Mask using Directional Systems

    DEFF Research Database (Denmark)

    Boldt, Jesper; Kjems, Ulrik; Pedersen, Michael Syskind;

    2008-01-01

    and the requirements to enable calculations of the ideal binary mask using a directional system without the availability of the unmixed signals. The proposed method has a low complexity and is verified using computer simulation in both ideal and non-ideal setups showing promising results....

  18. Accretion Events in Binary Systems: AZ Cas and VV Cep

    CERN Document Server

    Gałan, C; Tomov, T; Wiȩcek, M; Majcher, A; Wychudzki, P; Świerczyński, E; Kolev, D; Brożek, T; Maciejewski, G; Zoła, S; Kurpińska-Winiarska, M; Winiarski, M; Ogłoza, W; Drożdż, M; Krzesiński, J

    2011-01-01

    The sudden lengthening of orbital period of VV Cep eclipsing binary by about 1% was observed in the last epoch. The mass transfer and/or mass loss are most possible explanations of this event. The photometric behaviour of AZ Cas, the cousin of VV Cep, suggests that the accretion can occur and could be important in this system, too.

  19. The Lick-Carnegie Survey: A New Two-Planet System Around the Star HD 207832

    CERN Document Server

    Haghighipour, Nader; Rivera, Eugenio J; Henry, Gregory W; Vogt, Steven S

    2012-01-01

    Keck/HIRES precision radial velocities of HD 207832 indicate the presence of two Jovian-type planetary companions in Keplerian orbits around this G star. The planets have minimum masses of 0.56 and 0.73 Jupiter-masses with orbital periods of ~162 and ~1156 days, and eccentricities of 0.13 and 0.27, respectively. Stromgren b and y photometry reveals a clear stellar rotation signature of the host star with a period of 17.8 days, well separated from the period of the radial velocity variations, reinforcing their Keplerian origin. The values of the semimajor axes of the planets suggest that these objects have migrated from the region of giant planet formation to closer orbits. In order to examine the possibility of the existence of additional (small) planets in the system, we studied the orbital stability of hypothetical terrestrial-sized objects in the region between the two planets and interior to the orbit of the inner body. Results indicated that stable orbits exist only in a small region interior to planet b...

  20. Rotational mixing in massive binaries: detached short-period systems

    CERN Document Server

    de Mink, S E; Langer, N; Pols, O R; Brott, I; Yoon, S -Ch

    2009-01-01

    Models of rotating single stars can successfully account for a wide variety of observed stellar phenomena, such as the surface enhancements of N and He. However, recent observations have questioned the idea that rotational mixing is the main process responsible for the surface enhancements, emphasizing the need for a strong and conclusive test. We investigate the consequences of rotational mixing for massive main-sequence stars in short-period binaries. In these systems the tides spin up the stars to rapid rotation. We use a state-of-the-art stellar evolution code including the effect of rotational mixing, tides, and magnetic fields. We discuss the surface abundances expected in massive close binaries (M1~20 solar masses) and we propose using such systems to test the concept of rotational mixing. As these short-period binaries often show eclipses, their parameters can be determined with high accuracy, allowing for a direct comparison with binary evolution models. In more massive close systems (M1~50 solar mas...

  1. The new Wolf-Rayet binary system WR62a

    CERN Document Server

    Collado, A; Barbá, R H

    2013-01-01

    Context. A significant number of the Wolf-Rayet stars seem to be binary or multiple systems, but the nature of many of them is still unknown. Dedicated monitoring of WR stars favours the discovery of new systems. Aims. We explore the possibility that WR62a is a binary system. Methods. We analysed the spectra of WR62a, obtained between 2002 and 2010, to look for radial-velocity and spectral variations that would suggest there is a binary component. We searched for periodicities in the measured radial velocities and determined orbital solutions. A period search was also performed on the "All-Sky Automated Survey" photometry. Results. We find that WR62a is a double-lined spectroscopic binary with a WN5 primary star and an O 5.5-6 type secondary component in orbit with a period of 9.1447 d. The minimum masses range between 21 and 23 Mo for the WN star and between 39 and 42 Mo for the O-type star, thus indicating that the WN star is less massive than the O-type component. We detect a phase shift in the radial-velo...

  2. Estimating gravitational radiation from super-emitting compact binary systems

    CERN Document Server

    Hanna, Chad; Lehner, Luis

    2016-01-01

    Binary black hole mergers are among the most violent events in the Universe, leading to extreme warping of spacetime and copious emission of gravitational radiation. Even though black holes are the most compact objects they are not necessarily the most efficient emitters of gravitational radiation in binary systems. The final black hole resulting from a binary black hole merger retains a significant fraction of the pre-merger orbital energy and angular momentum. A non-vacuum system can in principle shed more of this energy than a black hole merger of equivalent mass. We study these super-emitters through a toy model that accounts for the possibility that the merger creates a compact object that retains a long-lived time-varying quadrupole moment. This toy model can capture the merger of neutron stars, but it can also be used to consider more exotic compact binaries. We hope that this toy model can serve as a guide to more rigorous numerical investigations into these systems.

  3. VX Her: Eclipsing Binary System or Single Variable Star

    Science.gov (United States)

    Perry, Kathleen; Castelaz, Michael; Henson, Gary; Boghozian, Andrew

    2015-01-01

    VX Her is a pulsating variable star with a period of .4556504 days. It is believed to be part of an eclipsing binary system (Fitch et al. 1966). This hypothesis originated from Fitch seeing VX Her's minimum point on its light curve reaching a 0.7 magnitude fainter than normal and remaining that way for nearly two hours. If VX Her were indeed a binary system, I would expect to see similar results with a fainter minimum and a broader, more horizontal dip. Having reduced and analyzed images from the Southeastern Association for Research in Astronomy Observatory in Chile and Kitt Peak, as well as images from a 0.15m reflector at East Tennessee State University, I found that VX Her has the standard light curve of the prototype variable star, RR Lyrae. Using photometry, I found no differing features in its light curve to suggest that it is indeed a binary system. However, more observations are needed in case VX Her is a wide binary.

  4. HD 207129: Dusty Debris at the Very Outer Edge of a Planetary System

    Science.gov (United States)

    Loehne, Torsten; Augereau, J.; Ertel, S.; Marshall, J.; Eiroa, C.; DUNES Consortium

    2011-09-01

    Debris disks are considered natural by-products of planet formation, and as such, they are important witnesses and tracers of this process. These disks of planetesimals and dust are left over where no planets could grow, typically at a system's cold periphery. The Herschel Open Time Key Program "DUNES" (DUst around NEarby Stars, PI: C. Eiroa) is a volume-limited survey that aims at the detection, characterization, and modeling of circumstellar debris disks as faint as a few times the Edgeworth-Kuiper Belt. Due to Herschel's wavelength coverage, sensitivity, and angular resolving power, the program was able to provide valuable new data points for known disks and to discover additional disks. For about one quarter of the stars in our unbiased sample, significant excess is detected, almost doubling the previous detection rates for Sun-like stars. Notably, a completely new regime of disks was explored, best described as extremely cold, both in terms of temperature and dynamical excitation. We will present these observational and modeling results, focusing on the particular case of HD 207129. That system is among the brighter, well-resolved objects of our sample and may thus serve as a calibrator for the study of unresolved disks. From HST observations, the dust in that system is known to originate from a belt at about 160 AU from the star -- the most distant birth ring known so far. Due to its sheer size, the surprisingly large grains, and the potentially major role of transport towards the star, that system may well be characterized as a key piece in a so-far poorly sampled region of the jigsaw puzzle of planet formation.

  5. Physical parameters of components in close binary systems: V

    CERN Document Server

    Zola, S; Zakrzewski, B; Kjurkchieva, D P; Marchev, D V; Baran, A; Rucinski, S M; Ogloza, W; Siwak, M; Koziel, D; Drozdz, M; Pokrzywka, B

    2009-01-01

    The paper presents combined spectroscopic and photometric orbital solutions for ten close binary systems: CN And, V776 Cas, FU Dra, UV Lyn, BB Peg, V592 Per, OU Ser, EQ Tau, HN UMa and HT Vir. The photometric data consist of new multicolor light curves, while the spectroscopy has been recently obtained within the radial velocity program at the David Dunlap Observatory (DDO). Absolute parameters of the components for these binary systems are derived. Our results confirm that CN And is not a contact system. Its configuration is semi-detached with the secondary component filling its Roche lobe. The configuration of nine other systems is contact. Three systems (V776 Cas, V592 Per and OU Ser) have high (44-77%) and six (FU Dra, UV Lyn, BB Peg, EQ Tau, HN UMa and HT Vir) low or intermediate (8-32%) fill-out factors. The absolute physical parameters are derived.

  6. Mass transfer in binary X-ray systems

    Science.gov (United States)

    Mccray, R.; Hatchett, S.

    1975-01-01

    The influence of X-ray heating on gas flows in binary X-ray systems is examined. A simple estimate is obtained for the evaporative wind flux from a stellar atmosphere due to X-ray heating which agrees with numerical calculations by Alme and Wilson (1974) but disagrees with calculations by Arons (1973) and by Basko and Sunyaev (1974) for the Her X-1/HZ Her system. The wind flux is sensitive to the soft X-ray spectrum. The self-excited wind mechanism does not work. Mass transfer in the Hercules system probably occurs by flow of the atmosphere of HZ Her through the gravitational saddle point of the system. The accretion gas stream is probably opaque with atomic density of not less than 10 to the 15th power per cu cm and is confined to a small fraction of 4(pi) steradians. Other binary X-ray systems are briefly discussed.

  7. Research on FM HD Radio System and Analysis on Coverage Interference%FM HD Radio系统研究及覆盖干扰分析

    Institute of Scientific and Technical Information of China (English)

    盛国芳; 曹元莉; 吴智勇; 万戈

    2010-01-01

    我国目前尚未推出调频广播数字化标准,HDRadio是美国调幅/调频波段的数字广播标准并在美国本土和世界各国进行了测试和推广.本文主要介绍了FM HD Radio传输系统的相关技术及其传输性能,并结合一些国外实验室的测试结果讨论FM HD Radio的覆盖和干扰问题.

  8. UNDERSTANDING THE EVOLUTION OF CLOSE BINARY SYSTEMS WITH RADIO PULSARS

    Energy Technology Data Exchange (ETDEWEB)

    Benvenuto, O. G. [Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, 1900 La Plata, Buenos Aires (Argentina); De Vito, M. A. [Instituto de Astrofísica de La Plata (IALP), CCT-CONICET-UNLP. Paseo del Bosque S/N (B1900FWA), La Plata (Argentina); Horvath, J. E., E-mail: obenvenu@fcaglp.unlp.edu.ar, E-mail: adevito@fcaglp.unlp.edu.ar, E-mail: foton@astro.iag.usp.br [Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo R. do Matão 1226 (05508-090), Cidade Universitária, São Paulo SP (Brazil)

    2014-05-01

    We calculate the evolution of close binary systems (CBSs) formed by a neutron star (behaving as a radio pulsar) and a normal donor star, which evolve either to a helium white dwarf (HeWD) or to ultra-short orbital period systems. We consider X-ray irradiation feedback and evaporation due to radio pulsar irradiation. We show that irradiation feedback leads to cyclic mass transfer episodes, allowing CBSs to be observed in between episodes as binary radio pulsars under conditions in which standard, non-irradiated models predict the occurrence of a low-mass X-ray binary. This behavior accounts for the existence of a family of eclipsing binary systems known as redbacks. We predict that redback companions should almost fill their Roche lobe, as observed in PSR J1723-2837. This state is also possible for systems evolving with larger orbital periods. Therefore, binary radio pulsars with companion star masses usually interpreted as larger than expected to produce HeWDs may also result in such quasi-Roche lobe overflow states, rather than hosting a carbon-oxygen WD. We found that CBSs with initial orbital periods of P{sub i} < 1 day evolve into redbacks. Some of them produce low-mass HeWDs, and a subgroup with shorter P{sub i} becomes black widows (BWs). Thus, BWs descend from redbacks, although not all redbacks evolve into BWs. There is mounting observational evidence favoring BW pulsars to be very massive (≳ 2 M {sub ☉}). As they should be redback descendants, redback pulsars should also be very massive, since most of the mass is transferred before this stage.

  9. The California Planet Survey IV: A Planet Orbiting the Giant Star HD 145934 and Updates to Seven Systems with Long-Period Planets

    CERN Document Server

    Feng, Y Katherina; Nelson, Benjamin; Wang, Sharon X; Ford, Eric B; Marcy, Geoffrey W; Isaacson, Howard; Howard, Andrew W

    2015-01-01

    We present an update to seven stars with long-period planets or planetary candidates using new and archival radial velocities from Keck-HIRES and literature velocities from other telescopes. Our updated analysis better constrains orbital parameters for these planets, four of which are known multi-planet systems. HD 24040 b and HD 183263 c are super-Jupiters with circular orbits and periods longer than 8 yr. We present a previously unseen linear trend in the residuals of HD 66428 indicative on an additional planetary companion. We confirm that GJ 849 is a multi-planet system and find a good orbital solution for the c component: it is a $1 M_{\\rm Jup}$ planet in a 15 yr orbit (the longest known for a planet orbiting an M dwarf). We update the HD 74156 double-planet system. We also announce the detection of HD 145934 b, a $2 M_{\\rm Jup}$ planet in a 7.5 yr orbit around a giant star. Two of our stars, HD 187123 and HD 217107, at present host the only known examples of systems comprising a hot Jupiter and a planet...

  10. A thermodynamic assessment of the iron-lead binary system

    Energy Technology Data Exchange (ETDEWEB)

    Vaajamo, I., E-mail: Iina.Vaajamo@aalto.fi [Aalto University School of Chemical Technology, Metallurgical Thermodynamics and Modelling Research Group PL 16200, FI-00076 Aalto (Finland); Taskinen, P., E-mail: Pekka.Taskinen@aalto.fi [Aalto University School of Chemical Technology, Metallurgical Thermodynamics and Modelling Research Group PL 16200, FI-00076 Aalto (Finland)

    2011-09-20

    Highlights: {center_dot} Isothermal equilibration experiments of the Fe-Pb binary were conducted in a special quartz ampoule and analyzed with ICP and EPMA. {center_dot} The method enables to obtain two experimental points from each end of the phase diagram in one experiment. {center_dot} New experimental data of the Pb solubility to Fe(s) below the monotectic temperature was obtained. {center_dot} This study consists of the widest critical compilation of the literature data done of the Fe-Pb binary system done so far, corrected also some errors in previous assessments. {center_dot} More accurate thermodynamic description of the Fe-Pb binary and its phases were obtained. - Abstract: The thermodynamic properties and phase equilibria of the Fe-Pb binary system were assessed using the CALPHAD (CALculation of PHAse Diagrams) method based upon available literature data and results of isothermal equilibration experiments reported in this paper. The phase diagram and excess Gibbs energy values of the solution phases, namely the molten alloy and the {gamma}-fcc and {alpha}- and {delta}-bcc solid solutions were expressed using Redlich-Kister polynomials. The experimental data were fitted by a least squares method using the MTDATA software. Agreement between experimental and calculated values is good. In particular the description of the solubility of lead in iron below the monotectic temperature has been improved.

  11. Astrometry, radial velocity, and photometry: the HD 128311 system remixed with data from HST, HET, and APT

    Energy Technology Data Exchange (ETDEWEB)

    McArthur, Barbara E.; Benedict, G. Fritz.; Cochran, William D. [McDonald Observatory, University of Texas at Austin, Austin, TX 78712 (United States); Henry, Gregory W. [Center of Excellence in Information Systems, Tennessee State University, 3500 John A. Merritt Blvd., P.O. Box 9501, Nashville, TN 37209 (United States); Hatzes, Artie [Thüringer Landessternwarte, Sternwarte 5, D-07778 Tautenburg (Germany); Harrison, Tom E. [Department of Astronomy, New Mexico State, Las Cruces, NM 88003 (United States); Johns-Krull, Chris [Department of Physics and Astronomy, Rice University, MS-108, 6100 Main Street, Houston, TX 77005 (United States); Nelan, Ed, E-mail: mca@astro.as.utexas.edu [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)

    2014-11-01

    We have used high-cadence radial velocity measurements from the Hobby-Eberly Telescope with published velocities from the Lick 3 m Shane Telescope, combined with astrometric data from the Hubble Space Telescope (HST) Fine Guidance Sensors to refine the orbital parameters of the HD 128311 system, and determine an inclination of 55.°95 ± 14.°55 and true mass of 3.789 {sub −0.432}{sup +0.924} M {sub JUP} for HD 128311 c. The combined radial velocity data also reveal a short period signal which could indicate a third planet in the system with an Msin i of 0.133 ± 0.005 M {sub JUP} or stellar phenomena. Photometry from the T12 0.8 m automatic photometric telescope at the Fairborn Observatory and HST are used to determine a photometric period close to, but not within the errors of the radial velocity signal. We performed a cross-correlation bisector analysis of the radial velocity data to look for correlations with the photometric period and found none. Dynamical integrations of the proposed system show long-term stability with the new orbital parameters of over 10 million years. Our new orbital elements do not support the claims of HD 128311 b and c being in mean motion resonance.

  12. Frequencies Shift in Relativistic Binary System (Theoretical Study)

    Science.gov (United States)

    El Fady Morcos, Abd

    2016-07-01

    A generalized formula for Kermack, McCrea and Whittaker (KMW), has been derived by the author and et al., to study the limb effect of massive rapidly rotating stars. In this work a modified Curzon exact solution for Einstein's field equations has been used to study the variation in the frequencies of signals' carriers from a relativistic binary system. The primary star is assumed to be massive with respect to the secondary one. The center of mass is considered to be coincident to the center of rotating polar coordinate system. The rotation of the secondary star around the primary star and Earth's observer rotates with the Earth are considered in our calculation. A general theoretical formula for the variation in the frequencies of the signals' carriers from a binary system is obtained

  13. Binary Systems as Resonance Detectors for Gravitational Waves

    CERN Document Server

    Hui, Lam; Yang, I-Sheng

    2012-01-01

    Gravitational waves at suitable frequencies can resonantly interact with a binary system, inducing changes to its orbit. A stochastic gravitational-wave background causes the orbital elements of the binary to execute a classic random walk -- with the variance of orbital elements growing with time. The lack of such a random walk in binaries that have been monitored with high precision over long time-scales can thus be used to place an upper bound on the gravitational-wave background. Using periastron time data from the Hulse-Taylor binary pulsar spanning ~30 years, we obtain a bound of h_c < 7.9 x 10^-14 at ~10^-4 Hz, where h_c is the strain amplitude per logarithmic frequency interval. Our constraint complements those from pulsar timing arrays, which probe much lower frequencies, and ground-based gravitational-wave observations, which probe much higher frequencies. Interesting sources in our frequency band, which overlaps the lower sensitive frequencies of proposed space-based observatories, include white-...

  14. The Pan-Pacific Planet Search. II. Confirmation of a two-planet system around HD 121056

    CERN Document Server

    Wittenmyer, Robert A; Liu, Fan; Horner, Jonathan; Endl, Michael; Johnson, John Asher; Tinney, C G; Carter, B D

    2014-01-01

    Precise radial velocities from the Anglo-Australian Telescope confirm the presence of a rare short-period planet around the K0 giant HD 121056. An independent two-planet solution using the AAT data shows that the inner planet has P=89.1+/-0.1 days, and m sin i=1.35+/-0.17 Mjup. These data also confirm the planetary nature of the outer companion, with m sin i=3.9+/-0.6 Mjup and a=2.96+/-0.16 AU. HD 121056 is the most-evolved star to host a confirmed multiple-planet system, and is a valuable example of a giant star hosting both a short-period and a long-period planet.

  15. Contribution \\`{a} l'etude des binaires des types F, G, K, M IX. HD 191588, nouvelle binaire spectroscopique \\`{a} raies simples de type RS Cvn, systeme triple

    CERN Document Server

    Griffin, R R F; Carquillat, J M; Griffin, Roger R.F.; Ginestet, Nicole; Carquillat, Jean-Michel

    2003-01-01

    An accident of misidentification has brought to light the interesting system HD 191588, a new RS CVn-type spectroscopic binary. A radial-velocity study of the primary star, the only seen component, carried out at the Observatoire de Haute-Provence with the Coravel instrument and subsequently at the Cambridge Observatories with a similar one, reveals two orbital motions: a short-period orbit (60 days) and a long-period one (about 4.5 years), so this star is a triple system. The following orbital elements are obtained: (1) for the long-period orbit P = 1667+/-17 days, T = 50901 +/-67 MJD, Gamma = +2.09 +/-0.07 km/s, K = 2.51 +/-0.13 km/s, e = 0.18 +/-0.04, omega = 228deg +/- 14 deg, a1 sin i = 56.7 +/- 3.0 Gm, f(m) = 0.0026 +/-0.0004 M_sun, and (2) for the short-period orbit P = 60.0269 +/-0.0016 days, T = 50482.6 +/-3.3 MJD, gamma is var., K = 24.03 +/- 0.09 km/s, e = 0.012 +/-0.004, omega = 233 deg +/-19deg, a1 sin i = 19.83 +/-0.07 Gm, f(m) = 0.0865 +/-0.0009 M_sun. From near-infrared observations we refine ...

  16. Camera link to HD-SDI interface converting system using FPGA%基于 FPGA 的 Camera Link 转 HD-SDI 接口转换系统

    Institute of Scientific and Technical Information of China (English)

    陈东成; 朱明; 郝志成; 刘剑

    2014-01-01

    Aiming at the shortcoming that Camera Link has complex interface and can only transfer in short distance,an interface converting system converting Camer Link to HD-SDI is designed.A high performance FPGA EP2S60F1020 of Altera Company is used to acquire the image data and code the data based on SMPTE 274M standard.To solve the problem that the horizontal and vertical time are different between Camera Link and HD-SDI,3 pieces of SDRAM are used as frame buffer.And the output frame of HD-SDI is delayed for a frame.The coded data is output to a serializer LMH0030, and the HD-SDI data is the output.As the vertical time of Camera Link and HD-SDI is not accurate the same,a frame must be dropped after every 708 frames.But the images being processed by the FP-GA are not dropped.The result shows that the system can convert images coming from Camera Link to HD-SDI.And the data output can be acquired by a SDI acquiring card.%由于 Camera Link 相机具有接口复杂、传输距离近等局限性,设计并实现了一种基于 FPGA 的 Camera Link 转HD-SDI 接口转换系统。该系统采用 Altera 公司的 EP2S60F1020高性能 FPGA 完成图像数据的采集并按 SMPTE 274M 标准编码;为解决 Camera Link 相机输出数据同 HD-SDI 输出图像行、场时间不同的问题,采用3片 SDRAM 作为帧缓存模块,延迟1帧输出;编码完成的数据输出到并串转换芯片 LMH0030,从而得到 HD-SDI 格式的视频输出。由于Camera Link 相机输出数据同 HD-SDI 输出图像的帧频并不绝对相同,每隔708帧必须丢去一帧数据,从而导致输出时固定丢帧,但 FPGA 对图像的处理并不会丢帧。实验结果表明,本系统能够将 Camera Link 相机输出的图像数据转换成HD-SDI 输出,并用采集卡采集到图像数据。

  17. Periodic orbits of planets in binary systems

    Science.gov (United States)

    Voyatzis, G.

    2017-03-01

    Periodic solutions of the three body problem are very important for understanding its dynamics either in a theoretical framework or in various applications in celestial mechanics. In this paper we discuss the computation and continuation of periodic orbits for planetary systems. The study is restricted to coplanar motion. Starting from known results of two-planet systems around single stars, we perform continuation of solutions with respect to the mass and approach periodic orbits of single planets in two-star systems. Also, families of periodic solutions can be computed for fixed masses of the primaries. When they are linearly stable, we can conclude about the existence of phase space domains of long-term orbital stability.

  18. HD 152246: a new high-mass triple system and its basic properties

    Science.gov (United States)

    Nasseri, A.; Chini, R.; Harmanec, P.; Mayer, P.; Nemravová, J. A.; Dembsky, T.; Lehmann, H.; Sana, H.; Le Bouquin, J.-B.

    2014-08-01

    Analyses of multi-epoch, high-resolution (R ~ 50 000) optical spectra of the O-type star HD 152246 (O9 IV according to the most recent classification), complemented by a limited number of earlier published radial velocities, led to the finding that the object is a hierarchical triple system, where a close inner pair (Ba-Bb) with a slightly eccentric orbit (e = 0.11) and a period of 6.^d0049 revolves in a 470-day highly eccentric orbit (e = 0.865) with another massive and brighter component A. The mass ratio of the inner system must be low since we were unable to find any traces of the secondary spectrum. The mass ratio A/(Ba+Bb) is 0.89. The outer system has recently been resolved using long-baseline interferometry on three occasions. The interferometry confirms the spectroscopic results and specifies elements of the system. Our orbital solutions, including the combined radial-velocity and interferometric solution indicate an orbital inclination of the outer orbit of 112° and stellar masses of 20.4 and 22.8 M⊙. We also disentangled the spectra of components A and Ba and compare them to synthetic spectra from two independent programmes, TLUSTY and FASTWIND. In either case, the fit was not satisfactory and we postpone a better determination of the system properties for a future study, after obtaining observations during the periastron passage of the outer orbit (the nearest chance being March 2015). For the moment, we can only conclude that component A is an O9 IV star with v sin i = 210 ± 10 km s-1and effective temperature of 33 000 ± 500 K, while component Ba is an O9 V object with v sin i = 65 ± 3 km s-1and Teff = 33 600 ± 600 K. Based on data products from observations made with ESO telescopes at La Silla Paranal Observatory under programmes 68.D-0095(A), 71.D-0369(A), 073.D-0609(A), 075.D-0061(A), 076.D0294(A), 077.D-0146(A), 079.D-0718(A), 081.D-2008(B), 083.D-0589(B), 086.D-0997(B), 087.D-0946(A), and 089.D-0975(A), extracted from the ESO/ST-ECF Science

  19. Is the X-ray pulsating companion of HD 49798 a possible type Ia supernova progenitor?

    CERN Document Server

    Liu, Dong-Dong; Wu, Cheng-Yuan; Wang, Bo

    2015-01-01

    HD 49798 (a hydrogen depleted subdwarf O6 star) with its massive white dwarf (WD) companion has been suggested to be a progenitor candidate of type Ia supernovae (SNe Ia). However, it is still uncertain whether the companion of HD 49798 is a carbon-oxygen (CO) WD or an oxygen-neon (ONe) WD. A CO WD will explode as an SN Ia when its mass grows approach to Chandrasekhar mass, while the outcome of an accreting ONe WD is likely to be a neutron star. We followed a series of Monte Carlo binary population synthesis approach to simulate the formation of ONe WD + He star systems. We found that there is almost no orbital period as large as HD 49798 with its WD companion in these ONe WD + He star systems based on our simulations, which means that the companion of HD 49798 might not be an ONe WD. We suggest that the companion of HD 49798 is most likely a CO WD, which can be expected to increase its mass to the Chandrasekhar mass limit by accreting He-rich material from HD 49798. Thus, HD 49798 with its companion may prod...

  20. Orbital Parameters for a Pre-Main Sequence Binary System

    Science.gov (United States)

    Karnath, Nicole; Prato, L.; Wasserman, L.

    2011-01-01

    The young system VSB 111 was originally classified as a single-lined spectroscopic binary in the star forming region of NGC 2264. Using the Keck II telescope we measured radial velocities for both the primary and secondary components in the infrared. By combining these data with previous visible light observations of the primary star, we derived the period, eccentricity, and other orbital parameters, as well as the mass ratio of the system. With additional information gained from further observations, for example the inclination derived from the angularly resolved orbit, we will eventually obtain the individual stellar masses, necessary to help to calibrate models of young star evolution. Furthermore, by compiling dozens or even hundreds of mass ratios for young binaries we can use mass ratio distributions to improve our understanding of binary star formation. No infrared excess or any other indication of a circumstellar disk is in evidence for VSB 111, indicating that either the accretion rate has dropped to an undetectable value or that this system has aged enough that its disk has dissipated, if originally present. Given the approximately 900 day period of this system, and its relatively high eccentricity, 0.8, the action of the companion could have been responsible for early dissipation of any disk material.

  1. Tenoxicam-kollicoat IR binary systems: physicochemical and biological evaluation.

    Science.gov (United States)

    Ibrahim, Mohamed Abbas

    2014-01-01

    Tenoxicam (TNX) binary systems in Kollicoat IR (KL) matrix were prepared in different drug: polymer ratios using kneading and spray-drying method. The prepared binary systems were characterized for drug dissolution rate, differential scanning calorimetry (DSC), IR spectroscopy and x-ray diffractometry. The results showed that the drug dissolution rate was remarkably enhanced by incorporating it in the KL matrix either by kneading or spray-drying, and the dissolution rate was increased by decreasing the drug weight ratio. The DSc and x-ray studies revealed the presence of TNX in less crystalline or amorphous state in its-KL binary systems. Moreover, the spray-dried TNX-KL system in 1:4 ratio, that exhibited the faster dissolution rate, was formulated in oral disintegrating tablets (ODTs). The data indicated that a fast disintegration and higher drug dissolution rate was achieved in case of the ODTs containing the spray-dried form compared to the ODTS containing untreated drug or the commercial tablet (Epicotil). Also, the drug exhibited significantly (p < 0.01) faster onset of the anti-inflammatory analgesic activities in case of the ODTs containing the spray-dried form, that was superior to that observed with both the commercial tablet product and the ODTS containing untreated drug.

  2. Deep, Low Mass Ratio Overcontact Binary Systems. XIV. A Statistical Analysis of 46 Sample Binaries

    Science.gov (United States)

    Yang, Yuan-Gui; Qian, Sheng-Bang

    2015-09-01

    A sample of 46 deep, low mass ratio (DLMR) overcontact binaries (i.e., q≤slant 0.25 and f≥slant 50%) is statistically analyzed in this paper. It is found that five relations possibly exist among some physical parameters. The primary components are little-evolved main sequence stars that lie between the zero-age main sequence line and the terminal-age main sequence (TAMS) line. Meanwhile, the secondary components may be evolved stars above the TAMS line. The super-luminosities and large radii may result from energy transfer, which causes their volumes to expand. The equations of M-L and M-R for the components are also determined. The relation of P-Mtotal implies that mass may escape from the central system when the orbital period decreases. The minimum mass ratio may preliminarily be {q}{min}=0.044(+/- 0.007) from the relations of q-f and q-Jspin/Jorb. With mass and angular momentum loss, the orbital period decreases, which finally causes this kind of DLMR overcontact binary to merge into a rapid-rotating single star.

  3. Be discs in binary systems I. Coplanar orbits

    CERN Document Server

    Panoglou, Despina; Vieira, Rodrigo G; Cyr, Isabelle H; Jones, Carol E; Okazaki, Atsuo T; Rivinius, Thomas

    2016-01-01

    Be stars are surrounded by outflowing circumstellar matter structured in the form of decretion discs. They are often members of binary systems, where it is expected that the decretion disc interacts both radiatively and gravitationally with the companion. In this work we study how various orbital (period, mass ratio, eccentricity) and disc (viscosity) parameters affect the disc structure in coplanar systems. We simulate such binaries with the use of a smoothed particle hydrodynamics code. The main effects of the secondary on the disc are its truncation and the accumulation of material inwards of truncation. In circular or nearly circular prograde orbits, the disc maintains a rotating, constant in shape, configuration, which is locked to the orbital phase. The disc is smaller in size, more elongated and more massive for low viscosity parameter, small orbital separation and/or high mass ratio. Highly eccentric orbits are more complex, with the disc structure and total mass strongly dependent on the orbital phas...

  4. Excess Molar Volume of Binary Systems Containing Mesitylene

    Directory of Open Access Journals (Sweden)

    Morávková, L.

    2013-05-01

    Full Text Available This paper presents a review of density measurements for binary systems containing 1,3,5-trimethylbenzene (mesitylene with a variety of organic compounds at atmospheric pressure. Literature data of the binary systems were divided into nine basic groups by the type of contained organic compound with mesitylene. The excess molar volumes calculated from the experimental density values have been compared with literature data. Densities were measured by a few experimental methods, namely using a pycnometer, a dilatometer or a commercial apparatus. The overview of the experimental data and shape of the excess molar volume curve versus mole fraction is presented in this paper. The excess molar volumes were correlated by Redlich–Kister equation. The standard deviations for fitting of excess molar volume versus mole fraction are compared. Found literature data cover a huge temperature range from (288.15 to 343.15 K.

  5. A new determination of the orbit and masses of the Be binary system delta Scorpii

    CERN Document Server

    Tango, W J; Jacob, A P; Méndez, A; North, J R; O'Byrne, J W; Seneta, E B; Tuthill, P G

    2008-01-01

    The binary star delta Sco (HD143275) underwent remarkable brightening in the visible in 2000, and continues to be irregularly variable. The system was observed with the Sydney University Stellar Interferometer (SUSI) in 1999, 2000, 2001, 2006 and 2007. The 1999 observations were consistent with predictions based on the previously published orbital elements. The subsequent observations can only be explained by assuming that an optically bright emission region with an angular size of > 2 +/- 1 mas formed around the primary in 2000. By 2006/2007 the size of this region grew to an estimated > 4 mas. We have determined a consistent set of orbital elements by simultaneously fitting all the published interferometric and spectroscopic data as well as the SUSI data reported here. The resulting elements and the brightness ratio for the system measured prior to the outburst in 2000 have been used to estimate the masses of the components. We find Ma = 15 +/- 7 Msun and Mb = 8.0 +/- 3.6 Msun. The dynamical parallax is est...

  6. Ordered Structures of a Binary Mixture with Mobile Particles System

    Institute of Scientific and Technical Information of China (English)

    诸跃进; 马余强

    2003-01-01

    We study the ordered structures of a binary mixture through the introduction of mobile particles under periodically oscillating driving fields, and find that the particle motion can break up the isotropy of the system, so that the continuous structure along the oscillation forcing direction is observed for properly chosen oscillating field.Furthermore, the dependences of the morphology and domain size on the mixture-particle coupling interaction,the diffusion coefficient, and the quench depth are examined in details.

  7. TAPAS - Tracking Advanced Planetary Systems with HARPS-N. II. Super Li-rich giant HD 107028

    CERN Document Server

    Adamow, M; Villaver, E; Wolszczan, A; Kowalik, K; Nowak, G; Adamczyk, M; Deka-Szymankiewicz, B

    2015-01-01

    Lithium rich giant stars are rare objects. For some of them, Li enrichment exceeds abundance of this element found in solar system meteorites, suggesting that these stars have gone through a Li enhancement process. We identified a Li rich giant HD 107028 with A(Li) > 3.3 in a sample of evolved stars observed within the PennState Torun Planet Search. In this work we study different enhancement scenarios and we try to identify the one responsible for Li enrichment for HD 107028. We collected high resolution spectra with three different instruments, covering different spectral ranges. We determine stellar parameters and abundances of selected elements with both equivalent width measurements and analysis, and spectral synthesis. We also collected multi epoch high precision radial velocities in an attempt to detect a companion. Collected data show that HD 107028 is a star at the base of Red Giant Branch. Except for high Li abundance, we have not identified any other anomalies in its chemical composition, and there...

  8. Benchmark ultra-cool dwarfs in widely separated binary systems

    Directory of Open Access Journals (Sweden)

    Jones H.R.A.

    2011-07-01

    Full Text Available Ultra-cool dwarfs as wide companions to subgiants, giants, white dwarfs and main sequence stars can be very good benchmark objects, for which we can infer physical properties with minimal reference to theoretical models, through association with the primary stars. We have searched for benchmark ultra-cool dwarfs in widely separated binary systems using SDSS, UKIDSS, and 2MASS. We then estimate spectral types using SDSS spectroscopy and multi-band colors, place constraints on distance, and perform proper motions calculations for all candidates which have sufficient epoch baseline coverage. Analysis of the proper motion and distance constraints show that eight of our ultra-cool dwarfs are members of widely separated binary systems. Another L3.5 dwarf, SDSS 0832, is shown to be a companion to the bright K3 giant η Cancri. Such primaries can provide age and metallicity constraints for any companion objects, yielding excellent benchmark objects. This is the first wide ultra-cool dwarf + giant binary system identified.

  9. Detection of a white dwarf in a visual binary system

    Science.gov (United States)

    Boehm-Vitense, Erika

    1992-01-01

    The F6 giant HD 160365 was detected to have a white dwarf companion about 8 arcsec south of the star. The UV energy distribution observed with IUE shows that the white dwarf has an effective temperature of 23,000 +/- 2000 K. If log g = 8 the Lya profile indicates an effective temperature around 24,500 K. Using the theoretical models by Wesemael et al. (1980) one finds a visual magnitude of m(V) about 16.5. For T(eff) = 24,500 K one expects for a white dwarf a luminosity of log L/L(solar) about 1.3 and M(V) about 10.67. This gives a distance modulus for the system of m(V) - M(V) = 5.83 and an absolute magnitude M(V)= 0.3 for the giant.

  10. WOBBLING AND PRECESSING JETS FROM WARPED DISKS IN BINARY SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Sheikhnezami, Somayeh [School of Astronomy, Institute for Research in Fundamental Sciences (IPM), Tehran (Iran, Islamic Republic of); Fendt, Christian, E-mail: nezami@mpia.de, E-mail: fendt@mpia.de [Max Planck Institute for Astronomy, Heidelberg (Germany)

    2015-12-01

    We present results of the first ever three-dimensional (3D) magnetohydrodynamic (MHD) simulations of the accretion–ejection structure. We investigate the 3D evolution of jets launched symmetrically from single stars but also jets from warped disks in binary systems. We have applied various model setups and tested them by simulating a stable and bipolar symmetric 3D structure from a single star–disk–jet system. Our reference simulation maintains a good axial symmetry and also a bipolar symmetry for more than 500 rotations of the inner disk, confirming the quality of our model setup. We have then implemented a 3D gravitational potential (Roche potential) due by a companion star and run a variety of simulations with different binary separations and mass ratios. These simulations show typical 3D deviations from axial symmetry, such as jet bending outside the Roche lobe or spiral arms forming in the accretion disk. In order to find indications of precession effects, we have also run an exemplary parameter setup, essentially governed by a small binary separation of only ≃200 inner disk radii. This simulation shows a strong indication that we observe the onset of a jet precession caused by the wobbling of the jet-launching disk. We estimate the opening angle of the precession cone defined by the lateral motion of the jet axis to be about 4° after about 5000 dynamical time steps.

  11. Self Regulated Shocks in Massive Star Binary Systems

    CERN Document Server

    Parkin, E R

    2013-01-01

    In an early-type, massive star binary system, X-ray bright shocks result from the powerful collision of stellar winds driven by radiation pressure on spectral line transitions. We examine the influence of the X-rays from the wind-wind collision shocks on the radiative driving of the stellar winds using steady state models that include a parameterized line force with X-ray ionization dependence. Our primary result is that X-ray radiation from the shocks inhibits wind acceleration and can lead to a lower pre-shock velocity, and a correspondingly lower shocked plasma temperature, yet the intrinsic X-ray luminosity of the shocks, LX remains largely unaltered, with the exception of a modest increase at small binary separations. Due to the feedback loop between the ionizing X-rays from the shocks and the wind-driving, we term this scenario as self regulated shocks. This effect is found to greatly increase the range of binary separations at which a wind-photosphere collision is likely to occur in systems where the m...

  12. On the dynamics of multiple systems of hot super-Earths and Neptunes: Tidal circularization, resonance and the HD 40307 system

    CERN Document Server

    Papaloizou, John C B

    2010-01-01

    [Abridged] We consider the dynamics of a system of hot super-Earths or Neptunes such as HD 40307. We show that, as tidal interaction with the central star leads to small eccentricities, the planets in this system could be undergoing resonant coupling even though the period ratios depart significantly from very precise commensurability. In a three planet system, this is indicated by the fact that resonant angles librate or are associated with long term changes to the orbital elements. We propose that the planets in HD 40307 were in a strict Laplace resonance while they migrated through the disc. After entering the disc inner cavity, tidal interaction would cause the period ratios to increase from two but with the inner pair deviating less than the outer pair, counter to what occurs in HD 40307. However, the relationship between these pairs that occurs in HD 40307 might be produced if the resonance is impulsively modified by an event like a close encounter shortly after the planetary system decouples from the d...

  13. 51 Eri and GJ 3305: A 10-15 Myr old binary star system at 30 parsecs

    CERN Document Server

    Feigelson, E D; Stark, M; Townsley, L; Garmire, G P; State, P; State, Penn

    2005-01-01

    Following the suggestion of Zuckerman et al. (2001, ApJ, 562, L87), we consider the evidence that 51 Eri (spectral type F0) and GJ 3305 (M0), historically classified as unrelated main sequence stars in the solar neighborhood, are instead a wide physical binary system and members of the young beta Pic moving group (BPMG). The BPMG is the nearest (d < 50 pc) of several groups of young stars with ages around 10 Myr that are kinematically convergent with the Oph-Sco-Cen Association (OSCA), the nearest OB star association. Combining SAAO optical photometry, Hobby-Eberly Telescope high-resolution spectroscopy, Chandra X-ray data, and UCAC2 catalog kinematics, we confirm with high confidence that the system is indeed extremely young. GJ 3305 itself exhibits very strong magnetic activity but has rapidly depleted most of its lithium. The 51 Eri/GJ 3305 system is the westernmost known member of the OSCA, lying 110 pc from the main subgroups. The system is similar to the BPMG wide binary HD 172555/CD -64d1208 and the...

  14. A SELF-CONSISTENT MODEL OF THE CIRCUMSTELLAR DEBRIS CREATED BY A GIANT HYPERVELOCITY IMPACT IN THE HD 172555 SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, B. C.; Melosh, H. J. [Department of Physics, Purdue University, 525 Northwestern Avenue, West Lafayette, IN 47907 (United States); Lisse, C. M. [JHU-APL, 11100 Johns Hopkins Road, Laurel, MD 20723 (United States); Chen, C. H. [STScI, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Wyatt, M. C. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); Thebault, P. [LESIA, Observatoire de Paris, F-92195 Meudon Principal Cedex (France); Henning, W. G. [NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771 (United States); Gaidos, E. [Department of Geology and Geophysics, University of Hawaii at Manoa, Honolulu, HI 96822 (United States); Elkins-Tanton, L. T. [Department of Terrestrial Magnetism, Carnegie Institution for Science, Washington, DC 20015 (United States); Bridges, J. C. [Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH (United Kingdom); Morlok, A., E-mail: johns477@purdue.edu [Department of Physical Sciences, Open University, Walton Hall, Milton Keynes MK7 6AA (United Kingdom)

    2012-12-10

    Spectral modeling of the large infrared excess in the Spitzer IRS spectra of HD 172555 suggests that there is more than 10{sup 19} kg of submicron dust in the system. Using physical arguments and constraints from observations, we rule out the possibility of the infrared excess being created by a magma ocean planet or a circumplanetary disk or torus. We show that the infrared excess is consistent with a circumstellar debris disk or torus, located at {approx}6 AU, that was created by a planetary scale hypervelocity impact. We find that radiation pressure should remove submicron dust from the debris disk in less than one year. However, the system's mid-infrared photometric flux, dominated by submicron grains, has been stable within 4% over the last 27 years, from the Infrared Astronomical Satellite (1983) to WISE (2010). Our new spectral modeling work and calculations of the radiation pressure on fine dust in HD 172555 provide a self-consistent explanation for this apparent contradiction. We also explore the unconfirmed claim that {approx}10{sup 47} molecules of SiO vapor are needed to explain an emission feature at {approx}8 {mu}m in the Spitzer IRS spectrum of HD 172555. We find that unless there are {approx}10{sup 48} atoms or 0.05 M{sub Circled-Plus} of atomic Si and O vapor in the system, SiO vapor should be destroyed by photo-dissociation in less than 0.2 years. We argue that a second plausible explanation for the {approx}8 {mu}m feature can be emission from solid SiO, which naturally occurs in submicron silicate ''smokes'' created by quickly condensing vaporized silicate.

  15. Carrying a Torch for Dust in Binary Star Systems

    CERN Document Server

    Cotton, Daniel V; Bott, Kimberly; Kedziora-Chudczer, Lucyna; Bailey, Jeremy

    2016-01-01

    Young stars are frequently observed to host circumstellar disks, within which their attendant planetary systems are formed. Scattered light imaging of these proto-planetary disks reveals a rich variety of structures including spirals, gaps and clumps. Self-consistent modelling of both imaging and multi-wavelength photometry enables the best interpretation of the location and size distribution of disks' dust. Epsilon Sagittarii is an unusual star system. It is a binary system with a B9.5III primary that is also believed to host a debris disk in an unstable configuration. Recent polarimetric measurements of the system with the High Precision Polarimetric Instrument (HIPPI) revealed an unexpectedly high fractional linear polarisation, one greater than the fractional infrared excess of the system. Here we develop a spectral energy distribution model for the system and use this as a basis for radiative transfer modelling of its polarisation with the RADMC-3D software package. The measured polarisation can be repro...

  16. Measurement of the Spin-Orbit Alignment in the Exoplanetary System HD 189733

    CERN Document Server

    Winn, J N; Marcy, G W; Butler, R P; Vogt, S S; Henry, G W; Roussanova, A; Holman, M J; Enya, K; Narita, N; Suto, Y; Turner, E L; Winn, Joshua N.; Johnson, John Asher; Marcy, Geoffrey W.; Vogt, Steven S.; Henry, Gregory W.; Roussanova, Anna; Holman, Matthew J.; Enya, Keigo; Narita, Norio; Suto, Yasushi; Turner, Edwin L.

    2006-01-01

    We present spectroscopy of a transit of the exoplanet HD 189733b. By modeling the Rossiter-McLaughlin effect (the anomalous Doppler shift due to the partial eclipse of the rotating stellar surface), we find the angle between the sky projections of the stellar spin axis and orbit normal to be lambda = -1.4 +/- 1.1 deg. This is the third case of a ``hot Jupiter'' for which lambda has been measured. In all three cases lambda is small, ruling out random orientations with 99.96% confidence, and suggesting that the inward migration of hot Jupiters generally preserves spin-orbit alignment.

  17. The low mass ratio contact binary system V728 Herculis

    CERN Document Server

    Erkan, Naci

    2015-01-01

    We present the orbital period study and the photometric analys of the contact binary system V728 Her. Our orbital period analysis shows that the period of the system increases (dP/dt=1.92x10^-7dyr^-1) and the mass transfer rate from the less massive component to more massive one is 2.51x10^-8M_suny^-1. In addition, an advanced sinusoidal variation in period can be attributed to the light-time effect by a tertiary component or the Applegate mechanism triggered by the secondary component. The simultaneous multicolor BVR light and radial velocity curves solution indicates that the physical parameters of the system are M1=1.8M_sun, M2=0.28M_sun, R1=1.87R_sun, R2=0.82R_sun, L1=5.9L_sun, and L2=1.2L_sun. We discuss the evolutionary status and conclude that V728 Her is a deep (f=81%), low mass ratio (q=0.16) contact binary system.

  18. Intelligent binary schema matching system in heterogeneity environment

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    For the past three decades, interoperability among heterogeneous systems had been a hard nut to crack due to the schematic and semantic perspectives that exist between objects. These systems were built under different data models. As such, levels of the local schemas are semantically very poor due to the limited expressiveness of traditional data models in which they were designed. Further more, most of the existing schema integration architectural conponents are inadequately equipped to handle the mapping schemas, especially when the semantics and structural conflicts are involved. This paper introduces an Intelligent Binary Schema Matching system (IBSMS), which exploits the phenomenon of making its components intelligent. That's equipping its components such as translators and integrators with adequate knowledge about various data models. This allows the components acquire enough intelligence to maneuver or manipulate the correspondence between constructs from different models. In addition, the system has a Binary Matcher, which compares the attribute correspondences of various databases in a pairwise form, in order to establish the equivalences. With the establishment of the mappings, the users shall be able to access them (mappings) for their desired usage.

  19. The Formation and Evolution of Planetary Systems (FEPS): Discovery of an Unusual Debris System Associated with HD 12039

    CERN Document Server

    Hines, D C; Bouwman, J; Hillenbrand, L A; Carpenter, J M; Meyer, M R; Kim, J S; Silverstone, M D; Rodmann, J; Wolf, S; Mamajek, E E; Brooke, T Y; Padgett, D L; Henning, T; Moro-Martin, A; Stobie, E B; Gordon, K D; Morrison, J E; Muzerolle, J; Su, K Y L

    2006-01-01

    We report the discovery of a debris system associated with the $\\sim 30$ Myr old G3/5V star HD 12039 using {\\it Spitzer Space Telescope} observations from 3.6 -- 160$\\mu$m. An observed infrared excess (L$_{\\rm IR}$/L$_{\\ast} = 1\\times10^{-4}$) above the expected photosphere for $\\lambda \\gtrsim 14\\mu$m is fit by thermally emitting material with a color temperature of T$\\sim 110$ K, warmer than the majority of debris disks identified to date around Sun-like stars. The object is not detected at 70$\\mu$m with a 3$\\sigma$ upper limit 6 times the expected photospheric flux. The spectrum of the infrared excess can be explained by warm, optically thin material comprised of blackbody-like grains of size $\\gtrsim 7 \\mu$m that reside in a belt orbiting the star at 4--6 AU. An alternate model dominated by smaller grains, near the blow-out size $a\\sim 0.5\\mu$m, located at 30-40AU is also possible, but requires the dust to have been produced recently since such small grains will be expelled from the system by radiation pr...

  20. Microwave spectroscopy of the seeded binary and ternary clusters CO-(pH2)2, CO-pH2-He, CO-HD, and CO-(oD2)N=1,2

    Science.gov (United States)

    Raston, Paul L.; Jäger, Wolfgang

    2015-04-01

    We report the Fourier transform microwave spectra of the a-type J = 1-0 transitions of the binary and ternary CO-(pH2)2, CO-pH2-He, CO-HD, and CO-(oD2)N=1,2 clusters. In addition to the normal isotopologue of CO for all clusters, we observed the transitions of the minor isotopologues, 13C16O, 12C18O, and 13C18O, for CO-(pH2)2 and CO-pH2-He. All transitions lie within 335 MHz of the experimentally or theoretically predicted values. In comparison to previously reported infrared spectra [Moroni et al., J. Chem. Phys. 122, 094314 (2005)], we are able to tentatively determine the vibrational shift for CO-pH2-He, in addition to its b-type J = 1-0 transition frequency. The a-type frequency of CO-pH2-He is similar to that of CO-He2 [Surin et al., Phys. Rev. Lett. 101, 233401 (2008)], suggesting that the pH2 molecule has a strong localizing effect on the He density. Perturbation theory analysis of CO-oD2 reveals that it is approximately T-shaped, with an anisotropy of the intermolecular potential amounting to ˜9 cm-1.

  1. Microwave spectroscopy of the seeded binary and ternary clusters CO-(pH{sub 2}){sub 2}, CO-pH{sub 2}-He, CO-HD, and CO-(oD{sub 2}){sub N=1,2}

    Energy Technology Data Exchange (ETDEWEB)

    Raston, Paul L., E-mail: paul.raston@adelaide.edu.au [Department of Chemistry, University of Adelaide, SA 5005 (Australia); Jäger, Wolfgang [Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2 (Canada)

    2015-04-14

    We report the Fourier transform microwave spectra of the a-type J = 1-0 transitions of the binary and ternary CO-(pH{sub 2}){sub 2}, CO-pH{sub 2}-He, CO-HD, and CO-(oD{sub 2}){sub N=1,2} clusters. In addition to the normal isotopologue of CO for all clusters, we observed the transitions of the minor isotopologues, {sup 13}C{sup 16}O, {sup 12}C{sup 18}O, and {sup 13}C{sup 18}O, for CO-(pH{sub 2}){sub 2} and CO-pH{sub 2}-He. All transitions lie within 335 MHz of the experimentally or theoretically predicted values. In comparison to previously reported infrared spectra [Moroni et al., J. Chem. Phys. 122, 094314 (2005)], we are able to tentatively determine the vibrational shift for CO-pH{sub 2}-He, in addition to its b-type J = 1-0 transition frequency. The a-type frequency of CO-pH{sub 2}-He is similar to that of CO-He{sub 2} [Surin et al., Phys. Rev. Lett. 101, 233401 (2008)], suggesting that the pH{sub 2} molecule has a strong localizing effect on the He density. Perturbation theory analysis of CO-oD{sub 2} reveals that it is approximately T-shaped, with an anisotropy of the intermolecular potential amounting to ∼9 cm{sup −1}.

  2. Photometric data analysis of the eclipsing binary system AH Tauri

    CERN Document Server

    El-Sadek, M A; Essam, A; Rassem, M A

    2014-01-01

    Two sets of photometric observations of the system AH Tauri have been analyzed using the latest version of the Wilson-Devinney code. The results show that AH Tauri may classified as A-type of W-UMa eclipsing binary. The mass ratio of q = 0.81, an over-contact degree of f = 0.095, and a slightly temperature difference between the two components have been obtained. The asymmetry of its light curve explained by the presence of a dark spot on the massive component. The physical, geometrical, and absolute parameters have been derived and compared with previous work.

  3. Properties of the components in young binary systems

    Science.gov (United States)

    Woitas, Jens

    1999-10-01

    Using near-infrared speckle-interferometry we have obtained resolved JHK-photometry for the components of 58 young binary systems. By placing the components into a color-color diagram we identify some unusual red objects that are candidates for infrared companions or substellar objects. We place a subsample that consists of the components of 14 weak-lined TTS systems (where no significant circumstellar excess emission is expected) into a color-magnitude diagram and show that in all these systems the components are coeval within the uncertainties. Particularly this is the case for the triple system HBC 358. Using the J-magnitude as an indicator for the stellar luminosity, the optical spectral type of the system and the previously justified assumption that all components are coeval we can place the components into the HRD and derive their masses by comparison with theoretical pre-main sequence evolutionary tracks. The results are the following: The distribution of mass ratios is neither clustered towards M2 / M1 = 1 nor is it a function of the primary's mass or the components' projected separation. Comparison of these results with predictions of theoretical multiple star formation models suggests that most of the systems have formed by fragmentation during protostellar collapse, and that the components' masses are principally determined by fragmentation and not by the following accretion processes. Furthermore the infrared source HV Tau C is discussed using new observational data. We show that this source is no Herbig-Haro object, but an active T Tauri star. So the HV Tau-system does not impose a problem on current models of T Tauri stars and their environment. From relative positions of the components at different epochs we derive their relative velocities and show that in most close systems orbital motion can be proved. The analysis of this orbital motion leads to an empirical mass estimate for T Tauri-stars which is larger than the masses one would expect from the

  4. Non-thermal radio emission from O-type stars. I. HD 168112

    CERN Document Server

    Blomme, R; De Becker, M; Rauw, G; Runacres, M C; Gunawan, D Y A S; Chapman, J M

    2005-01-01

    We present a radio lightcurve of the O5.5 III(f+) star HD 168112, based on archive data from the Very Large Array (VLA) and the Australia Telescope Compact Array (ATCA). The fluxes show considerable variability and a negative spectral index, thereby confirming that HD 168112 is a non-thermal radio emitter. The non-thermal radio emission is believed to be due to synchrotron radiation from relativistic electrons that have been Fermi accelerated in shocks. For HD 168112, it is not known whether these shocks are due to a wind-wind collision in a binary system or to the intrinsic instability of the stellar wind driving mechanism. Assuming HD 168112 to be a single star, the Van Loo et al. (2005) synchrotron model shows that the velocity jump of the shocks should be very high, or there should be a very large number of shocks in the wind. Neither of these is compatible with time-dependent hydrodynamical calculations of O star winds. If, on the other hand, we assume that HD 168112 is a binary, the high velocity jump i...

  5. Radio observations of HD 93129A: The earliest O star with the highest mass loss ?

    CERN Document Server

    Benaglia, P; Benaglia, Paula; Koribalski, Baerbel

    2004-01-01

    We present the results of radio continuum observations towards the open cluster Tr 14, where our main targets are the early-type O stars HD 93129A/B and HD 93128. The observations were carried out at 3 cm (8.64 GHz) and 6 cm (4.80 GHz) with the Australia Telescope Compact Array. Only HD 93129A (type O2 If*) was detected; we measure flux densities of S_(3cm) = 2.0 +- 0.2 mJy and S_(6cm) = 4.1 +- 0.4 mJy. The resulting spectral index of alpha = -1.2 +- 0.3 (S_(nu) = k . nu^alpha) indicates predominantly non-thermal emission, suggesting HD 93129A may be a binary system. We propose that the observed 3 cm radio emission is mostly coming from the non-thermal wind collision region of a binary, and, to a lesser extent, from the thermal winds of the primary and secondary stars in HD 93129A. At a stellar distance of 2.8 kpc, we derive a mass-loss rate M_dot = 5.1 x 10^(-5) M_sun/yr, assuming the thermal fraction of the 3 cm emission is about 0.5.

  6. Observational Evidence for Tidal Interaction in Close Binary Systems

    CERN Document Server

    Mazeh, Tsevi

    2008-01-01

    This paper reviews the rich corpus of observational evidence for tidal effects in short-period binaries. We review the evidence for ellipsoidal variability and for the observational manifestation of apsidal motion in eclipsing binaries. Among the long-term effects, circularization was studied the most, and a transition period between circular and eccentric orbits has been derived for eight coeval samples of binaries. As binaries are supposed to reach synchronization before circularization, one can expect finding eccentric binaries in pseudo-synchronization state, the evidence for which is reviewed. The paper reviews the Rossiter-McLaughlin effect and its potential to study spin-orbit alignment. We discuss the tidal interaction in close binaries that are orbited by a third distant companion, and review the effect of pumping the binary eccentricity by the third star. We then discuss the idea that the tidal interaction induced by the eccentricity modulation can shrink the binary separation. The paper discusses t...

  7. Thermodynamic reassessment of Ni-Pr binary system

    Energy Technology Data Exchange (ETDEWEB)

    Rahou, Z., E-mail: rahou.zakarea@gmail.com; Mahdouk, K.; Moustain, D.; Otmani, S.; Kardellass, S.; Iddaoudi, A.; Selhaoui, N.

    2015-01-25

    Highlights: • The Ni-Pr has been re-assessed using the latest experimental results. • The enthalpies of formation of NiPr and Ni{sub 5}Pr measured by Kleppa were considered her for the first time. • The errors of related modeling presented in previous articles have been modified. • A self-consistent thermodynamic description of the Sm–Ni system was obtained. - Abstract: Based on the available experimental data of phase equilibria and thermodynamic properties from the literature, the Ni-Pr binary system has been thermodynamically assessed using the CALPHAD method. The solution phases, Liquid, FCC{sub A}1, DHCP and BCC{sub A}2 were modeled as substitutional solution phases, for which the excess Gibbs energies were formulated with Redlich–Kister polynomials. All intermetallic phases were described as stoichiometric compounds. Subsequently, a set of self-consistent thermodynamic parameters describing various phases in this binary system has been obtained. The calculated results reproduce well the corresponding experimental data.

  8. Thermodynamic assessment of the Bi-Mg binary system

    Institute of Scientific and Technical Information of China (English)

    Chunju NIU; Changrong LI; Zhenmin DU; Cuiping GUO; Yongjuan JING

    2012-01-01

    The Bi-Mg binary system had been assessed by adopting the ionic melt and the modified quasi-chemical models to describe the liquid phase with short range ordering behavior.In general considerations of the development of the thermodynamic database of the multi-component Mg-based alloys and the consistency of the thermodynamic models of the related phases,the Gibbs energy descriptions of all the phases in the Bi-Mg binary system were reasonably re-modeled and critically re-assessed in the present work.Especially for the liquid phase,the associate model was used with the constituent species Bi,Mg and Bi2Mg3.The Mg-rich terminal phase hcp_A3 was modeled as a substitutional solution following Redlich-Kister equation and the Bi-rich terminal phase Rhombohedral_A7 was treated as a pure Bi substance since the extremely small solubility of Mg in Bi. The low and high temperature nonstoichiometric compounds β-Bi2Mg3 and α-Bi2Mg3 were described by the sublattice models (Bi,Va)2Mg3 and (Bi)1 (Bi,Va)aMg6 respectively based on their structure features.A set of self-consistent thermodynamic parameters of the Bi-Mg system was obtained and the experimental thermodynamic and phase equilibrium data were well reproduced by the optimized thermodynamic data.

  9. A new detached K7 dwarf eclipsing binary system

    CERN Document Server

    Young, T B; Webb, J K; Ashley, M C B; Christiansen, J L; Derekas, A; Nutto, C

    2006-01-01

    We present an analysis of a new, detached, double-lined eclipsing binary system with K7 Ve components, discovered as part of the University of New South Wales Extrasolar Planet Search. The object is significant in that only 6 other binary systems are known with comparable or lower mass. Such systems offer important tests of mass-radius theoretical models. Follow-up photometry and spectroscopy were obtained with the 40-inch and 2.3m telescopes at SSO respectively. An estimate of the radial velocity amplitude from spectral absorption features, combined with the orbital inclination (83.5 deg) estimated from lightcurve fitting, yielded a total mass of M=(1.041 +/- 0.06)M_sun and component masses of M_A=(0.529 +/- 0.035)M_sun and M_B=(0.512 +/- 0.035)M_sun. The radial velocity amplitude estimated from absorption features (167 +/- 3)kmps was found to be less than the estimate from the H_alpha emission lines (175 +/- 1.5)kmps. The lightcurve fit produced radii of R_A=(0.641 +/- 0.05)R_sun and R_B=(0.608 +/- 0.06)R_s...

  10. Pulsating red giant stars in eccentric binary systems discovered from Kepler space-based photometry

    CERN Document Server

    Beck, P G; Vos, J; Kallinger, T; Bloemen, S; Tkachenko, A; García, R A; Østensen, R H; Aerts, C; Kurtz, D W; De Ridder, J; Hekker, S; Pavlovski, K; Mathur, S; De Smedt, K; Derekas, A; Corsaro, E; Mosser, B; Van Winckel, H; Huber, D; Degroote, P; Davies, G R; Prša, A; Debosscher, J; Elsworth, Y; Nemeth, P; Siess, L; Schmid, V S; Pápics, P I; de Vries, B L; van Marle, A J; Marcos-Arenal, P; Lobel, A

    2013-01-01

    The unparalleled photometric data obtained by NASA's Kepler space telescope led to an improved understanding of red giant stars and binary stars. Seismology allows us to constrain the properties of red giants. In addition to eclipsing binaries, eccentric non-eclipsing binaries, exhibiting ellipsoidal modulations, have been detected with Kepler. We aim to study the properties of eccentric binary systems containing a red giant star and derive the parameters of the primary giant component. We apply asteroseismic techniques to determine masses and radii of the primary component of each system. For a selected target, light and radial velocity curve modelling techniques are applied to extract the parameters of the system. The effects of stellar on the binary system are studied. The paper presents the asteroseismic analysis of 18 pulsating red giants in eccentric binary systems, for which masses and radii were constrained. The orbital periods of these systems range from 20 to 440days. From radial velocity measuremen...

  11. HD 80606: searching for the chemical signature of planet formation

    Science.gov (United States)

    Saffe, C.; Flores, M.; Buccino, A.

    2015-10-01

    Context. Binary systems with similar components are ideal laboratories that allow several physical processes to be tested, such as the possible chemical pattern imprinted by the planet formation process. Aims: We explore the probable chemical signature of planet formation in the remarkable binary system HD 80606-HD 80607. The star HD 80606 hosts a giant planet with ~4 MJup detected by both transit and radial velocity techniques, which is one of the most eccentric planets detected to date. We study condensation temperature Tc trends of volatile and refractory element abundances to determine whether there is a depletion of refractories, which could be related to the terrestrial planet formation. Methods: We carried out a high-precision abundance determination in both components of the binary system via a line-by-line, strictly differential approach. First, we used the Sun as a reference and then we used HD 80606. The stellar parameters Teff, log g, [Fe/H] and vturb were determined by imposing differential ionization and excitation equilibrium of Fe I and Fe II lines, with an updated version of the program FUNDPAR, together with plane-parallel local thermodynamic equilibrium (LTE) ATLAS9 model atmospheres and the MOOG code. Then, we derived detailed abundances of 24 different species with equivalent widths and spectral synthesis with the program MOOG. The chemical patterns were compared with the solar-twins Tc trends of Meléndez et al. (2009, AJ, 704, L66) and with a sample of solar-analogue stars with [Fe/H] ~ +0.2 dex from Neves et al. (2009, A&A, 497, 563). The Tc trends were also compared mutually between both stars of the binary system. Results: From the study of Tc trends, we concluded that the stars HD 80606 and HD 80607 do not seem to be depleted in refractory elements, which is different for the case of the Sun. Then, following the interpretation of Meléndez et al. (2009), the terrestrial planet formation would have been less efficient in the components of

  12. HD Radio传输系统实验室性能测试%Transmission System Laboratory Performance Testing of HD Radio

    Institute of Scientific and Technical Information of China (English)

    盛国芳; 吴智勇; 曹元莉

    2009-01-01

    HD Radio是美国AM与FM波段的数字广播标准,为了了解其信号的传输性能及其在我国实际播出环境及广播频道规划条件下,与邻频道广播电台之间相互干扰的情况,需要对其传输性能进行实验室测试和场地测试,为我国调频频段广播数字化提供技术参考依据.本文主要探讨实验室性能测试的相关技术和方法.

  13. Thermodynamic optimization of Co–Ge binary system

    Energy Technology Data Exchange (ETDEWEB)

    Dong, S.S.; Liu, S.G. [School of Materials Science and Engineering, Central South University, Changsha, Hunan 410083 (China); Tao, X.M. [College of Physical Science and Technology, Guangxi University, Nanning, Guangxi 530004 (China); Xiao, F.H.; Huang, L.H.; Yang, F.; He, Y.; Chen, Q. [School of Materials Science and Engineering, Central South University, Changsha, Hunan 410083 (China); Liu, H.S., E-mail: hsliu@csu.edu.cn [School of Materials Science and Engineering, Central South University, Changsha, Hunan 410083 (China); Jin, Z.P. [School of Materials Science and Engineering, Central South University, Changsha, Hunan 410083 (China)

    2013-11-20

    Graphical abstract: - Highlights: • The Co–Ge binary system was reassessed and optimized. • The first-principle approach was employed to calculate formation enthalpies of two compounds. • A self-consistent set of thermodynamic parameters was obtained. • The experimental data were well reproduced in the present optimization. - Abstract: Phase diagram of Co–Ge binary system was thermodynamically assessed by using CALPHAD approach in this study. The excess Gibbs energy of the solution phases, liquid, α(Co) and ε(Co), were modeled with Redlich–Kister polynomial. Magnetic contribution to the Gibbs energy was also taken into account for α(Co) and ε(Co). Considering its crystal structure and solubility range, the intermetallic compound βCo{sub 5}Ge{sub 3}, with B8{sub 2}-structure, was particularly described with a three-sublattice model, (Co,Va){sub 1}:(Co){sub 4}:(Co,Ge){sub 3}. And the compound CoGe was described with two-sublattice model according to its crystal structure. Other intermetallic compounds were described as stoichiometric phases because of their narrow homogeneity ranges or unknown crystal structure. In order to obtain a reasonable description of several Co–Ge compounds, first-principle calculations were performed before optimization to determine their formation enthalpies. Finally, a set of thermodynamic parameters was finally obtained so that most data of phase boundaries and thermodynamic properties of various phases were reproduced in present optimization.

  14. New systemic radial velocities of suspected RR Lyrae binary stars

    CERN Document Server

    Guggenberger, Elisabeth; Kolenberg, Katrien

    2015-01-01

    Among the tens of thousands of known RR Lyrae stars there are only a handful that show indications of possible binarity. The question why this is the case is still unsolved, and has recently sparked several studies dedicated to the search for additional RR Lyraes in binary systems. Such systems are particularly valuable because they might allow to constrain the stellar mass. Most of the recent studies, however, are based on photometry by finding a light time effect in the timings of maximum light. This approach is a very promising and successful one, but it has a major drawback: by itself, it cannot serve as a definite proof of binarity, because other phenomena such as the Blazhko effect or intrinsic period changes could lead to similar results. Spectroscopic radial velocity measurements, on the other hand, can serve as definite proof of binarity. We have therefore started a project to study spectroscopically RR Lyrae stars that are suspected to be binaries. We have obtained radial velocity (RV) curves with t...

  15. Close stellar binary systems by grazing envelope evolution

    CERN Document Server

    Soker, Noam

    2014-01-01

    I suggest a spiral-in process by which a stellar companion graze the envelope of a giant star while both the orbital separation and the giant radius shrink simultaneously, and a close binary system is formed. The binary system might be viewed as evolving in a constant state of `just entering a common envelope (CE) phase'. In cases where this process takes place it can be an alternative to the CE evolution where the secondary star is immerses in the giant's envelope. The grazing envelope evolution (GEE) is made possible only if the companion manages to accreted mass at a high rate and launch jets that remove the outskirts of the giant envelope, hence preventing the formation of a CE . The high accretion rate is made possible by the accretion disk that launches jets that efficiently carry the excess angular momentum and energy from the accreted mass. Mass loss through the second Lagrangian point can carry additional angular momentum and envelope mass. The GEE lasts for tens to hundreds of years. The high accret...

  16. DETERMINATION OF DIFFUSION COEFFICIENTS OF BINARY LIQUID SYSTEMS

    Directory of Open Access Journals (Sweden)

    Erol İNCE

    2001-03-01

    Full Text Available The diaphragm cell method technique was used to determine the diffusion coefficients of selected binary systems (Cyclopentanol-Acetic acid, Cyclohexanol-Acetic acid and Methylcyclohexanol-Acetic acid. The technique was chosen because of simplicity and accuracy. The stirring rate was 60 rpm. The diaphragm cell was calibrated at 298.15 K by diffusing of 0.1 N KCl solution into distilled water. The experimental diaphragm cell constant (ß was found 0.09293 cm -2 . The temperature of water bath was controlled by a contact thermometer with an accuracy of ± 0.1 °C. The obtained experimental diffusion coefficients for Cyclopentanol-Acetic acid, Cyclohexanol-Acetic acid and Methylcyclohexanol - Acetic acid binary systems were 2.40 x 10 -5 cm 2 /s, 1.16 x 10 -5 cm 2 /s, 3.97 x 10 -5 cm 2 /s, respectively. Furthermore, diffusion coefficients have been estimated by the theoretical methods of Wilke - Chang and Scheibel equations and compared with the experimental results.

  17. The Habitable Zone of the Binary System Kepler-16

    Science.gov (United States)

    Moorman, Sarah; Cuntz, Manfred

    2017-01-01

    We report on the current results and envisioned future work from our study of the binary star system Kepler-16, which consists of a K-type main-sequence star and an M dwarf as well as a circumbinary Saturnian planet, Kepler-16b. We focus on the calculation of the location and extent of the habitable zone while considering several criteria for both the inner and outer boundaries previously given in the literature. In particular, we investigate the impact of the two stellar components (especially Kepler-16A) as well as of the system’s binarity regarding the provision of circumbinary habitability. Another aspect of our work consists in a careful assessment of how the extent of the system’s habitable zone is impacted by the relative uncertainties of the stellar and system parameters. Finally, we comment on the likelihood of habitable objects in the system by taking into account both radiative criteria and the need of orbital stability.

  18. Binary mass ratios: system mass not primary mass

    CERN Document Server

    Goodwin, Simon P

    2012-01-01

    Binary properties are usually expressed (for good observational reasons) as a function of primary mass. It has been found that the distribution of companion masses -- the mass ratio distribution -- is different for different primary masses. We argue that system mass is the more fundamental physical parameter to use. We show that if system masses are drawn from a log-normal mass function, then the different observed mass ratio distributions as a function of primary mass, from M-dwarfs to A-stars, are all consistent with a universal, flat, system mass ratio distribution. We also show that the brown dwarf mass ratio distribution is not drawn from the same flat distribution, suggesting that the process which decides upon mass ratios is very different in brown dwarfs and stars.

  19. Modulated Gamma-ray emission from compact millisecond pulsar binary systems

    CERN Document Server

    Bednarek, W

    2013-01-01

    A significant amount of the millisecond pulsars has been discovered within binary systems. In several such binary systems the masses of the companion stars have been derived allowing to distinguish two classes of objects, called the Black Widow and the Redback binaries. Pulsars in these binary systems are expected to produce winds which, colliding with stellar winds, create conditions for acceleration of electrons. These electrons should interact with the anisotropic radiation from the companion stars producing gamma-ray emission modulated with the orbital period of the binary system. We consider the interaction of a millisecond pulsar (MSP) wind with a very inhomogeneous stellar wind from the companion star within binary systems of the Black Widow and Redback types. It is expected that the pulsar wind should mix efficiently with the inhomogeneous stellar wind. Electrons accelerated in such mixed, turbulent winds can interact with the magnetic field and also strong radiation from the companion star producing ...

  20. Planetary Nebulae that Cannot Be Explained by Binary Systems

    Science.gov (United States)

    Bear, Ealeal; Soker, Noam

    2017-03-01

    We examine the images of hundreds of planetary nebulae (PNe) and find that for about one in six PNe the morphology is too “messy” to be accounted for by models of stellar binary interaction. We speculate that interacting triple stellar systems shaped these PNe. In this preliminary study, we qualitatively classify PNe by one of four categories. (1) PNe that show no need for a tertiary star to account for their morphology. (2) PNe whose structure possesses a pronounced departure from axial-symmetry and/or mirror-symmetry. We classify these, according to our speculation, as “having a triple stellar progenitor.” (3) PNe whose morphology possesses departure from axial-symmetry and/or mirror-symmetry, but not as pronounced as in the previous class, and are classified as “likely shaped by triple stellar system.” (4) PNe with minor departure from axial-symmetry and/or mirror-symmetry that could have been also caused by an eccentric binary system or the interstellar medium. These are classified as “maybe shaped by a triple stellar system.” Given a weight η t = 1, η l = 0.67, and η m = 0.33 to classes 2, 3, and 4, respectively, we find that according to our assumption about 13%–21% of PNe have been shaped by triple stellar systems. Although in some evolutionary scenarios not all three stars survive the evolution, we encourage the search for a triple stellar systems at the center of some PNe.

  1. On the ultraviolet anomalies of the WASP-12 and HD 189733 systems: Trojan satellites as a plasma source

    CERN Document Server

    Kislyakova, K G; Funk, B; Lammer, H; Fossati, L; Eggl, S; Schwarz, R; Boudjada, M Y; Erkaev, N V

    2016-01-01

    We suggest an additional possible plasma source to explain part of the phenomena observed for the transiting hot Jupiters WASP-12b and HD 189733b in their ultraviolet (UV) light curves. In the proposed scenario, material outgasses from the molten surface of Trojan satellites on tadpole orbits near the Lagrange points L$_4$ and L$_5$. We show that the temperature at the orbital location of WASP-12b is high enough to melt the surface of rocky bodies and to form shallow lava oceans on them. In case of WASP-12b, this leads to the release of elements such as Mg and Ca, which are expected to surround the system. The predicted Mg and Ca outgassing rates from two Io-sized WASP-12b Trojans are $\\approx 2.2 \\times 10^{27}$ s$^{-1}$ and $\\approx 2.2 \\times 10^{26}$ s$^{-1}$, respectively. Trojan outgassing can lead to the apparent lack of emission in Mg{\\sc ii}\\,h\\&k and Ca{\\sc ii}\\,H\\&K line cores of WASP-12. For HD 189733b, the mechanism is only marginally possible due to the lower temperature. This may be one...

  2. Research on application of HD video conference system%高清视频会议系统的应用研究

    Institute of Scientific and Technical Information of China (English)

    段云丰

    2014-01-01

    According to the functions and characteristics of HD video conference system,the application of HD video con-ference system in power generation company is discussed. The construction and operation of HD video conferencing system are investigated. The further development trend is pointed out in this paper.%结合高清视频会议系统的功能与特点,探讨了高清视频会议系统在调峰调频发电公司的应用,对高清视频会议系统的建设和运行进行了分析研究,并指出进一步发展趋势。

  3. Accurate absolute parameters of the binary system V4089 Sgr

    CERN Document Server

    Veramendi, M E

    2014-01-01

    We carried out a spectroscopic-photometric analysis of the binary V4089 Sgr with the aim to obtain absolute masses and radii of the components and to contrast these parameters with stellar evolution theoretical models. We took high-resolution spectra and measured radial velocity using standard cross-correlations and a technique of spectral disentangling. Absolute parameters of the components were determined through the simultaneous fitting of measured radial velocities and Geneva photometric data available in the literature. In this way we obtained Ma=2.584+-0.008 Msun, Mb=1.607+-0.007 Msun, Ra=3.959+-0.013 Rsun, and Rb=1.605+-0.016 Rsun. The comparison of these parameters with two grids of theoretical models led to estimate narrow ranges of possible values for system metallicity and age. According circularization theory it is not expected that the binary had been achieved a circular orbit as a result of tidal friction, so the null eccentricity found is an interesting fact. On the other hand, we measured proj...

  4. Evolution of an Accretion Disk in Binary Black Hole Systems

    CERN Document Server

    Kimura, Shigeo S; Toma, Kenji

    2016-01-01

    We investigate evolution of an accretion disk in binary black hole (BBH) systems, the importance of which is now increasing due to its close relationship to possible electromagnetic counterparts of the gravitational waves (GWs) from mergers of BBHs. Perna et al. (2016) proposed a novel evolutionary scenario of an accretion disk in BBHs in which a disk eventually becomes "dead", i.e., the magnetorotational instability (MRI) becomes inactive. In their scenario, the dead disk survives until {\\it a few seconds before} the merger event. We improve the dead disk model and propose another scenario, taking account of effects of the tidal torque from the companion and the critical ionization degree for MRI activation more carefully. We find that the mass of the dead disk is much lower than that in the Perna's scenario. When the binary separation sufficiently becomes small, the tidal heating reactivates MRI and mass accretion onto the black hole (BH). We also find that this disk "revival" happens {\\it many years before...

  5. Evolution of an accretion disc in binary black hole systems

    Science.gov (United States)

    Kimura, Shigeo S.; Takahashi, Sanemichi Z.; Toma, Kenji

    2017-03-01

    We investigate evolution of an accretion disc in binary black hole (BBH) systems and possible electromagnetic counterparts of the gravitational waves from mergers of BBHs. Perna et al. proposed a novel evolutionary scenario of an accretion disc in BBHs in which a disc eventually becomes 'dead', i.e. the magnetorotational instability (MRI) becomes inactive. In their scenario, the dead disc survives until a few seconds before the merger event. We improve the dead disc model and propose another scenario, taking account of effects of the tidal torque from the companion and the critical ionization degree for MRI activation more carefully. We find that the mass of the dead disc is much lower than that in the Perna's scenario. When the binary separation sufficiently becomes small, the mass inflow induced by the tidal torque reactivates MRI, restarting mass accretion on to the black hole. We also find that this disc 'revival' happens more than thousands of years before the merger. The mass accretion induced by the tidal torque increases as the separation decreases, and a relativistic jet could be launched before the merger. The emissions from these jets are too faint compared to gamma-ray bursts, but detectable if the merger events happen within ≲10 Mpc or if the masses of the black holes are as massive as ∼105 M⊙.

  6. Collective Modes in Two Dimensional Binary Yukawa Systems

    CERN Document Server

    Kalman, Gabor J; Donko, Zoltan; Golden, Kenneth I; Kyrkos, Stamatios

    2013-01-01

    We analyze via theoretical approaches and molecular dynamics simulations the collective mode structure of strongly coupled two-dimensional binary Yukawa systems, for selected density, mass and charge ratios, both in the liquid and crystalline solid phases. Theoretically, the liquid phase is described through the Quasi-Localized Charge Approximation (QLCA) approach, while in the crystalline phase we study the centered honeycomb and the staggered rectangular crystal structures through the standard harmonic phonon approximation. We identify "longitudinal" and "transverse" acoustic and optic modes and find that the longitudinal acoustic mode evolves from its weakly coupled counterpart in a discontinuous non-perturbative fashion. The low frequency acoustic excitations are governed by the oscillation frequency of the average atom, while the high frequency optic excitation frequencies are related to the Einstein frequencies of the systems.

  7. Study on Critical Properties for CO2+Cosolvent Binary System and Ternary System

    Institute of Scientific and Technical Information of China (English)

    张敬畅; 吴向阳; 曹维良

    2002-01-01

    The performance of supercritical fluid (SCF) as a solvent can be greatly affected by addition of anentrainer to the system. In this study, a constant volume visual method is used to measure the critical point ofCO2+n-butyraldehyde, CO2+ i-butyraldehyde and CO2+alcohol binary systems and CO2+entrainer+trisodiumsalt of tri-(m-sulfonphenyl)phosphine (TPPTS) ternary systems, which provides us good theoretical basis for super-critical extraction and chemical reaction. The relationship between critical point and concentration of the entrainerare discussed. The phase behavior of binary system and that of ternary system are compared. The relationshipbetween the concentration of TPPTS and critical point of binary systems are also discussed.

  8. NEWLY DISCOVERED PLANETS ORBITING HD 5319, HD 11506, HD 75784 AND HD 10442 FROM THE N2K CONSORTIUM

    Energy Technology Data Exchange (ETDEWEB)

    Giguere, Matthew J.; Fischer, Debra A.; Brewer, John M. [Department of Astronomy, Yale University, 260 Whitney Avenue, New Haven, CT 06511 (United States); Payne, Matthew J.; Johnson, John Asher [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Howard, Andrew W. [Institute for Astronomy, University of Hawaii at Manoa, Honolulu, HI 96822 (United States); Isaacson, Howard T. [Department of Astronomy, University of California, Berkeley, Berkeley, California 94720 (United States)

    2015-01-20

    Initially designed to discover short-period planets, the N2K campaign has since evolved to discover new worlds at large separations from their host stars. Detecting such worlds will help determine the giant planet occurrence at semi-major axes beyond the ice line, where gas giants are thought to mostly form. Here we report four newly discovered gas giant planets (with minimum masses ranging from 0.4 to 2.1 M {sub Jup}) orbiting stars monitored as part of the Next 2000 target stars (N2K) Doppler Survey program. Two of these planets orbit stars already known to host planets: HD 5319 and HD 11506. The remaining discoveries reside in previously unknown planetary systems: HD 10442 and HD 75784. The refined orbital period of the inner planet orbiting HD 5319 is 641 days. The newly discovered outer planet orbits in 886 days. The large masses combined with the proximity to a 4:3 mean motion resonance make this system a challenge to explain with current formation and migration theories. HD 11506 has one confirmed planet, and here we confirm a second. The outer planet has an orbital period of 1627.5 days, and the newly discovered inner planet orbits in 223.6 days. A planet has also been discovered orbiting HD 75784 with an orbital period of 341.7 days. There is evidence for a longer period signal; however, several more years of observations are needed to put tight constraints on the Keplerian parameters for the outer planet. Lastly, an additional planet has been detected orbiting HD 10442 with a period of 1043 days.

  9. Newly Discovered Planets Orbiting HD 5319, HD 11506, HD 75784 and HD 10442 from the N2K Consortium

    Science.gov (United States)

    Giguere, Matthew J.; Fischer, Debra A.; Payne, Matthew J.; Brewer, John M.; Johnson, John Asher; Howard, Andrew W.; Isaacson, Howard T.

    2015-01-01

    Initially designed to discover short-period planets, the N2K campaign has since evolved to discover new worlds at large separations from their host stars. Detecting such worlds will help determine the giant planet occurrence at semi-major axes beyond the ice line, where gas giants are thought to mostly form. Here we report four newly discovered gas giant planets (with minimum masses ranging from 0.4 to 2.1 M Jup) orbiting stars monitored as part of the Next 2000 target stars (N2K) Doppler Survey program. Two of these planets orbit stars already known to host planets: HD 5319 and HD 11506. The remaining discoveries reside in previously unknown planetary systems: HD 10442 and HD 75784. The refined orbital period of the inner planet orbiting HD 5319 is 641 days. The newly discovered outer planet orbits in 886 days. The large masses combined with the proximity to a 4:3 mean motion resonance make this system a challenge to explain with current formation and migration theories. HD 11506 has one confirmed planet, and here we confirm a second. The outer planet has an orbital period of 1627.5 days, and the newly discovered inner planet orbits in 223.6 days. A planet has also been discovered orbiting HD 75784 with an orbital period of 341.7 days. There is evidence for a longer period signal; however, several more years of observations are needed to put tight constraints on the Keplerian parameters for the outer planet. Lastly, an additional planet has been detected orbiting HD 10442 with a period of 1043 days. Based on observations obtained at the W. M. Keck Observatory, which is operated by the University of California and the California Institute of Technology. Keck time has been granted by NOAO and NASA.

  10. Newly-Discovered Planets Orbiting HD~5319, HD~11506, HD~75784 and HD~10442 from the N2K Consortium

    CERN Document Server

    Giguere, Matthew J; Payne, Matthew J; Brewer, John M; Johnson, John Asher; Howard, Andrew W; Isaacson, Howard T

    2014-01-01

    Initially designed to discover short-period planets, the N2K campaign has since evolved to discover new worlds at large separations from their host stars. Detecting such worlds will help determine the giant planet occurrence at semi-major axes beyond the ice line, where gas giants are thought to mostly form. Here we report four newly-discovered gas giant planets (with minimum masses ranging from 0.4 to 2.1 MJup) orbiting stars monitored as part of the N2K program. Two of these planets orbit stars already known to host planets: HD 5319 and HD 11506. The remaining discoveries reside in previously-unknown planetary systems: HD 10442 and HD 75784. The refined orbital period of the inner planet orbiting HD 5319 is 641 days. The newly-discovered outer planet orbits in 886 days. The large masses combined with the proximity to a 4:3 mean motion resonance make this system a challenge to explain with current formation and migration theories. HD 11506 has one confirmed planet, and here we confirm a second. The outer pla...

  11. THE McDONALD OBSERVATORY PLANET SEARCH: NEW LONG-PERIOD GIANT PLANETS AND TWO INTERACTING JUPITERS IN THE HD 155358 SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, Paul; Endl, Michael; Cochran, William D.; MacQueen, Phillip J.; Brugamyer, Erik J.; Barnes, Stuart I.; Caldwell, Caroline [Department of Astronomy and McDonald Observatory, University of Texas at Austin, Austin, TX 78712 (United States); Wittenmyer, Robert A.; Horner, J. [Department of Astrophysics and Optics, School of Physics, University of New South Wales, Sydney NSW 2052 (Australia); Simon, Attila E., E-mail: paul@astro.as.utexas.edu [Konkoly Observatory of the Hungarian Academy of Sciences, P.O. Box 67, H-1525 Budapest (Hungary)

    2012-04-10

    We present high-precision radial velocity (RV) observations of four solar-type (F7-G5) stars-HD 79498, HD 155358, HD 197037, and HD 220773-taken as part of the McDonald Observatory Planet Search Program. For each of these stars, we see evidence of Keplerian motion caused by the presence of one or more gas giant planets in long-period orbits. We derive orbital parameters for each system and note the properties (composition, activity, etc.) of the host stars. While we have previously announced the two-gas-giant HD 155358 system, we now report a shorter period for planet c. This new period is consistent with the planets being trapped in mutual 2:1 mean-motion resonance. We therefore perform an in-depth stability analysis, placing additional constraints on the orbital parameters of the planets. These results demonstrate the excellent long-term RV stability of the spectrometers on both the Harlan J. Smith 2.7 m telescope and the Hobby-Eberly telescope.

  12. Near-Infrared Observations of Compact Binary Systems

    Science.gov (United States)

    Khargharia, Juthika

    Low mass X-ray binaries (LMXBs) are a subset of compact binary systems in which a main-sequence or slightly evolved star fills its Roche lobe and donates mass to a neutron star or a black hole (BH) via an accretion disk. Robust estimates of compact object masses in these systems are required to enhance our current understanding of the physics of compact object formation, accretion disks and jets. Compact object masses are typically determined at near-infrared (NIR) wavelengths when the system is in quiescence and the donor star is the dominant source of flux. Previous studies have assumed that any non-stellar contribution at these wavelengths is minimal. However, this assumption is rarely true. By performing NIR spectroscopy, we determined the fractional donor star contribution to the NIR flux and the compact object masses in two LMXBs: V404 Cyg and Cen X-4. In our analysis, it was assumed that the light curve morphology remains consistent throughout quiescence. It has now been shown in several systems that veiling measurements from non-stellar sources are meaningful only if acquired contemporaneously with light curve measurements. We accounted for this in the measurement of the BH mass in the LMXB, XTE J1118+480. LMXBs are also considered to be the most likely candidates responsible for the formation of milli-second pulsars (MSP). Here, I present the unique case of PSR J1903+0327 that challenges this currently accepted theory of MSP formation and is a potential candidate for testing General Relativity. Observations in the NIR come with their own set of challenges. NIR detector arrays used in these observations generally have high dark current and readout noise. In an effort to lower the read noise in NICFPS at APO, we present a study done on the Hawaii-1RG engineering grade chip that served as a test bed for reducing the read noise in NICFPS.

  13. HD Radio系统中预留子载波降低PAPR的方法研究%Tone Reservation Scheme of PAPR Reduction in HD Radio System

    Institute of Scientific and Technical Information of China (English)

    方伟伟; 陈远知; 周德扬

    2014-01-01

    HD Radio standard is the best choice for FM analog broadcasting digitalization, for its realizing digital broadcasting with in-band on-channel ( IBOC) technology in the same band of current FM analog broadcasting. However, the simultaneous sending of analog signal and digital signal by the antenna would bring large coupling loss, and to reduce the peak-to-average power ratio ( PAPR ) of the digital signal would become the main means to decrease the coupling loss. Among all schemes to reduce PAPR, tone res-ervation ( TR) scheme receives widespread concern for its not disturbing the data signal, while the core of TR method is the selection of reserved subcarriers. In this paper, a novel scheme based on metric value for reserved subcarriers is proposed. The scheme employs a metric to measure how much each subcarrier con-tributes to the large samples and then the subcarriers with the largest metrics are selected as reserved sub-carriers. The simulation results indicate that when 30 reserved subcarriers are selected, the PAPR gain of the proposed method could reach 0 . 79 dB at least at the probability of 10-3 .%HD Radio标准中使用的“带内同频( IBOC)”技术在现有FM模拟广播的同频带内实现数字广播,无需打破现有的频率规划,是调频模拟广播数字化的最佳选择。然而模拟信号和数字信号同时通过混合天线发射时产生的耦合损耗非常大,降低数字信号的峰均比是减小损耗的有力措施。在降低峰均比的所有方案中,预留子载波法由于不引起信号的失真而受到广泛的关注,而预留子载波法的核心即是预留子载波位置的选取。基于HD Radio系统提出一种基于度量的预留子载波位置的选取方法,该方法通过一个度量值来衡量每个子载波对时域大幅度采样值的贡献,并选取具有最大的正度量值的子载波作为预留子载波。仿真结果表明,当使用30个预留子载波时,在概率为10-3时

  14. Separated Fringe Packet Observations with the CHARA Array II: $\\omega$ Andromeda, HD 178911, and {\\xi} Cephei

    CERN Document Server

    Farrington, Christopher D; Mason, Brian D; Hartkopf, William I; Mourard, Denis; Moravveji, Ehsan; McAlister, Harold A; Turner, Nils H; Sturmann, Laszlo; Sturmann, Judit

    2014-01-01

    When observed with optical long-baseline interferometers (OLBI), components of a binary star which are sufficiently separated produce their own interferometric fringe packets; these are referred to as Separated Fringe Packet (SFP) binaries. These SFP binaries can overlap in angular separation with the regime of systems resolvable by speckle interferometry at single, large-aperture telescopes and can provide additional measurements for preliminary orbits lacking good phase coverage, help constrain elements of already established orbits, and locate new binaries in the undersampled regime between the bounds of spectroscopic surveys and speckle interferometry. In this process, a visibility calibration star is not needed, and the separated fringe packets can provide an accurate vector separation. In this paper, we apply the SFP approach to {\\omega} Andromeda, HD 178911, and {\\xi} Cephei with the CLIMB three-beam combiner at the CHARA Array. For these systems we determine component masses and parallax of 0.963${\\pm...

  15. Adaptive optics imaging of the MBM 12 association. Seven binaries and an edge-on disk in a quadruple system

    Science.gov (United States)

    Chauvin, G.; Ménard, F.; Fusco, T.; Lagrange, A.-M.; Beuzit, J.-L.; Mouillet, D.; Augereau, J.-C.

    2002-11-01

    We report adaptive optics (AO) observations of the young and nearby association MBM 12 obtained with the Canada-France-Hawaii Telescope. Our main observational result is the discovery of six new binary systems, LkHα 264, E 0255+2018, RX J0255.4+2005, S18, MBM 12-10, RX J0255.3+1915, and the confirmation of HD 17332, already known as a binary. We also detected a possible quadruple system. It is composed of the close binary LkHα 263 AB (separation of ~ 0.41''), of LkHα 262 located ~ 15.25'' from LkHα 263 A, and of LkHα 263 C, located ~ 4.1'' from LkHα 263 A. A preliminary study of the binary fraction suggests a binary excess in the MBM 12 association as compared to the field and IC 348. Because of the high binarity rate, previous estimations of spectral types and measurements of IR excesses for several candidate members of MBM 12 have to be revised. LkHα 263 C is a nebulous object that we interpret as a disk oriented almost perfectly edge-on and seen in scattered light. This object has already been reported by Jayawardhana et al. (\\cite{Jayawardhana2002}). Scattered light models allow us to estimate some of the structural parameters (i.e. inclination, diameter and to a lesser extent dust mass) of the circumstellar disk. We find an inclination of 89o and a outer radius for the disk, ~ 165 AU if the distance to MBM 12 is 275 pc. With the present data set, we do not attempt to re-assess the distance to MBM 12. We estimate however that the distance to the candidate member RX J0255.3+1915 is d > 175 pc. Based on data collected at the Canada-France-Hawaii Telescope. The CFHT corporation is funded by the Governments of Canada and France, and by the University of Hawaii.

  16. Effect of the Salmonella pathogenicity island 2 type III secretion system on Salmonella survival in activated chicken macrophage-like HD11 cells.

    Directory of Open Access Journals (Sweden)

    Amanda L S Wisner

    Full Text Available In order to better identify the role of the Salmonella pathogenicity island 2 (SPI-2 type III secretion system (T3SS in chickens, we used the well-known gentamicin protection assay with activated HD11 cells. HD11 cells are a macrophage-like chicken cell line that can be stimulated with phorbol 12-myristate 13-acetate (PMA to exhibit more macrophage-like morphology and greater production of reactive oxygen species (ROS. Activated HD11 cells were infected with a wild-type Salmonella enterica subspecies enterica serovar Typhimurium (S. Typhimurium strain, a SPI-2 mutant S. Typhimurium strain, a wild-type Salmonella enterica subspecies enterica serovar Enteritidis (S. Enteritidis strain, a SPI-2 mutant S. Enteritidis strain, or a non-pathogenic Escherichia coli (E. coli strain. SPI-2 mutant strains were found to survive as well as their parent strain at all time points post-uptake (PU by the HD11 cells, up to 24 h PU, while the E. coli strain was no longer recoverable by 3 h PU. We can conclude from these observations that the SPI-2 T3SS of S. Typhimurium and S. Enteritidis is not important for survival of Salmonella in the activated macrophage-like HD11 cell line, and that Salmonella must employ other mechanisms for survival in this environment, as E. coli is effectively eliminated.

  17. Thermodynamic assessment of the Ni-Sb binary system

    Institute of Scientific and Technical Information of China (English)

    CAO Zhanmin; TAKADU Yoshikazu; OHNUMA Ikuo; KAINUMA Ryosuke; ZHU Hongmin; ISHIDA Kiyohito

    2008-01-01

    The Ni-Sb binary alloy system was thermodynamically assessed using CALPHAD approach in this article.Excess Gibbs energies of solution phases,liquid and fcc phases,were formulated using the Redlich-Kister expression.The intermediate phases were modeled by the sublattice model with (Ni,Va)0.5(Ni,Sb)0.25(Ni)0.25 for Ni3Sb_HT phase and (Ni,Va)0.3333(Sb)0.3333(Ni,Va)0.3333 for NiSb phase.The other phases including Ni3Sb,Ni7Sb3,and NiSb2 were treated as stoichiometric compound owing to their narrow composition ranges.Based on the reported thermodynamic properties and phase diagram data,the thermodynamic parameters of these phases were optimized,and the obtained values can reproduce the available experimental data well.

  18. Thermodynamic modeling of the Ba - Mg binary system

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Xin; Li, Changrong; Du, Zhenmin; Guo, Cuiping; Chen, Sicheng [Univ. of Science and Technology, Beijing (China). School of Materials Science and Engineering

    2013-04-15

    On the basis of the thermochemical and phase equilibrium experimental data, the phase diagram of the Ba - Mg binary system has been assessed by means of the calculation of phase diagrams technique. The liquid phase is of unlimited solubility and modeled as a solution phase using the Redlich-Kister equation. The intermetallic compounds, Mg{sub 17}Ba{sub 2}, Mg{sub 23}Ba{sub 6} and Mg{sub 2}Ba, with no solubility ranges are treated as strict stoichiometric compounds with the formula Mg{sub m} Ba{sub n}. Two terminal phases, BccBa and HcpMg, are kept as solution phases, since the solubilities of the two phases are of considerable importance. After optimization, a set of self-consistent thermodynamic parameters has been obtained. The calculated values agree well with the available experimental data.

  19. Hybridizing Gravitationl Waveforms of Inspiralling Binary Neutron Star Systems

    Science.gov (United States)

    Cullen, Torrey; LIGO Collaboration

    2016-03-01

    Gravitational waves are ripples in space and time and were predicted to be produced by astrophysical systems such as binary neutron stars by Albert Einstein. These are key targets for Laser Interferometer and Gravitational Wave Observatory (LIGO), which uses template waveforms to find weak signals. The simplified template models are known to break down at high frequency, so I wrote code that constructs hybrid waveforms from numerical simulations to accurately cover a large range of frequencies. These hybrid waveforms use Post Newtonian template models at low frequencies and numerical data from simulations at high frequencies. They are constructed by reading in existing Post Newtonian models with the same masses as simulated stars, reading in the numerical data from simulations, and finding the ideal frequency and alignment to ``stitch'' these waveforms together.

  20. Complicated Structure of Interacting Young Binary System: Outflows and Gas-Streams

    Science.gov (United States)

    Pyo, Tae-Soo; Hayashi, M.; Beck, T. L.; Chris, C. J.; Takami, M.

    2014-07-01

    It is important to understand the formation and evolution of the young binary system because many young stars are born in binary or multiple systems. We report recent discovery of binary jet and wind from UY Aur system with high-angular resolution observation by using NIFS (NIR Integral Field Spectrograph) /GEMINI combined with adaptive optics system, Altair. The primary, UY Aur A, reveals widely opened wind while the secondary, UY Aur B, shows small jets in NIR [Fe II] emission. Outflows from low-mass young binary or multiple systems have been observed from a few tens of samples. Outflows are closely related mass accretion. Many simulations show an accretion flow toward the individual circumstellar disks from the outer circumbinary disk as well as a stream bridge between the circumstellar disks. We will discuss how to use TMT and ALMA for anatomy of young binary systems.

  1. The origin of the excess transit absorption in the HD 189733 system: planet or star?

    CERN Document Server

    Barnes, J R; Staab, D; Anglada-Escudé, G

    2016-01-01

    We have detected excess absorption in the emission cores of Ca II H & K during transits of HD 189733b for the first time. Using observations of three transits we investigate the origin of the absorption, which is also seen in H{\\alpha} and the Na I D lines. Applying differential spectrophotometry methods to the Ca II H and Ca II K lines combined, using respective passband widths of {\\Delta}{\\lambda} = 0.4 & 0.6 $\\AA$ yields excess absorption of t$_d$ = 0.0074 $\\pm$ 0.0044 (1.7{\\sigma}; Transit 1) and 0.0214 +/- 0.0022 (9.8{\\sigma}; Transit 2). Similarly, we detect excess H{\\alpha} absorption in a passband of width {\\Delta}{\\lambda} = 0.7 $\\AA$, with t$_d$ = 0.0084 $\\pm$ 0.0016 (5.2{\\sigma}) and 0.0121 $\\pm$ 0.0012 (9.9{\\sigma}). For both lines, Transit 2 is thus significantly deeper. Combining all three transits for the Na I D lines yields excess absorption of t$_d$ = 0.0041 $\\pm$ 0.0006 (6.5{\\sigma}). By considering the time series observations of each line, we find that the excess apparent absorptio...

  2. Cancer-specific binary expression system activated in mice by bacteriophage HK022 Integrase

    DEFF Research Database (Denmark)

    Elias, Amer; Spector, Itay; Sogolovsky-Bard, Ilana;

    2016-01-01

    Binary systems based on site-specific recombination have been used for tumor specific transcription targeting of suicide genes in animal models. In these binary systems a site specific recombinase or integrase that is expressed from a tumor specific promoter drives tumor specific expression...

  3. Orbital Parameters for Two Young Spectroscopic Binary Systems

    Science.gov (United States)

    Karnath, Nicole; Prato, L. A.; Wasserman, L. H.; Torres, G.; Mathieu, R. D.

    2013-01-01

    Orbital parameters for two young, low-mass, pre-main sequence binary systems are described. Originally, VSB 111 and VSB 126 had parameters reported based on single-lined spectroscopic solutions. High-resolution, infrared spectra were obtained with the Keck II telescope on Mauna Kea and used to identify the lines of the secondary stars, yielding double-lined orbital solutions that include the systems' mass ratios. VSB 126 has a period of 12.9247±0.0001 days, an eccentricity of 0.184±0.015, and a mass ratio of 0.27±0.01. VSB 111 has a period of 901.3062±1.1792 days, an eccentricity of 0.791±0.008, and a mass ratio of 0.60±0.06. The two systems are located in the ~3 Myr old star forming region NGC 2264, at a distance of ~800 pc. We compare the cluster age and dynamical properties of the stars in these systems with the masses and ages predicted by models of pre-main sequence evolution. Partial support for this work was provided by NSF grant AST-1009136 (to LP).

  4. Modeling Mergers of Known Galactic Systems of Binary Neutron Stars

    CERN Document Server

    Feo, Alessandra; Maione, Francesco; Löffler, Frank

    2016-01-01

    We present a study of the merger of six different known galactic systems of binary neutron stars (BNS) of unequal mass with a mass ratio between $0.75$ and $0.99$. Specifically, these systems are J1756-2251, J0737-3039A, J1906+0746, B1534+12, J0453+1559 and B1913+16. We follow the dynamics of the merger from the late stage of the inspiral process up to $\\sim$ 20 ms after the system has merged, either to form a hyper-massive neutron star (NS) or a rotating black hole (BH), using a semi-realistic equation of state (EOS), namely the seven-segment piece-wise polytropic SLy with a thermal component. For the most extreme of these systems ($q=0.75$, J0453+1559), we also investigate the effects of different EOSs: APR4, H4, and MS1. Our numerical simulations are performed using only publicly available open source code such as, the Einstein Toolkit code deployed for the dynamical evolution and the LORENE code for the generation of the initial models. We show results on the gravitational wave signals, spectrogram and fr...

  5. The non-thermal radio emitter HD 93250 resolved by long baseline interferometry

    CERN Document Server

    Sana, H; De Becker, M; Berger, J -P; de Koter, A; Merand, A; 10.1088/2041-8205/740/2/L43

    2011-01-01

    As the brightest O-type X-ray source in the Carina nebula, HD 93250 (O4 III(fc)) is X-ray overluminous for its spectral type and has an unusually hard X-ray spectrum. Two different scenarios have been invoked to explain its X-ray properties: wind-wind interaction and magnetic wind confinement. Yet, HD 93250 shows absolutely constant radial velocities over time scales of years suggesting either a single star, a binary system seen pole-one or a very long period and/or highly eccentric system. Using the ESO Very Large Telescope Interferometer, we resolved HD 93250 as a close pair with similar components. We measured a near-infrared flux ratio of 0.8+/-0.1 and a separation of 1.5+/-0.2 x 10E-03 arcsec. At the distance of Carina, this corresponds to a projected physical distance of 3.5 A.U. While a quantitative investigation would require a full characterization of the orbit, the binary nature of HD 93250 allows us to qualitatively explain both its X-ray flux and hardness and its non-thermal radio emission in the ...

  6. The nature of the late B-type stars HD 67044 and HD 42035

    CERN Document Server

    Monier, R; Royer, F

    2016-01-01

    While monitoring a sample of apparently slowly rotating superficially normal bright late B and early A stars in the northern hemisphere, we have discovered that HD 67044 and HD 42035, hitherto classified as normal late B-type stars, are actually respectively a new chemically peculiar star and a new spectroscopic binary containing a very slow rotator HD 42035 S with ultra-sharp lines (vsini = 3.7 km/s) and a fast rotator HD 42035 B with broad lines. The lines of Ti, Cr, Mn, Sr, Y, Zr and Ba are conspicuous features in the high resolution SOPHIE spectrum of HD 67044. The HgII line at 3983.93 A is also present as a weak feature. The composite spectrum of HD 42035 is characterised by very sharp lines formed in HD 42035 S superimposed onto the shallow and broad lines of HD 42035 B. These very sharp lines are mostly due to light elements from C to Ni, the only heavy species definitely present are Sr and Ba. Selected lines of 21 chemical elements from He up to Hg have been synthesized using model atmospheres compute...

  7. Maximum mass ratio of AM CVn-type binary systems and maximum white dwarf mass in ultra-compact X-ray binaries

    Directory of Open Access Journals (Sweden)

    Arbutina Bojan

    2011-01-01

    Full Text Available AM CVn-type stars and ultra-compact X-ray binaries are extremely interesting semi-detached close binary systems in which the Roche lobe filling component is a white dwarf transferring mass to another white dwarf, neutron star or a black hole. Earlier theoretical considerations show that there is a maximum mass ratio of AM CVn-type binary systems (qmax ≈ 2/3 below which the mass transfer is stable. In this paper we derive slightly different value for qmax and more interestingly, by applying the same procedure, we find the maximum expected white dwarf mass in ultra-compact X-ray binaries.

  8. HD 98800: A 10-Myr-Old Transition Disk

    CERN Document Server

    Furlan, E; Calvet, N; Forrest, W J; D'Alessio, P; Hartmann, L; Watson, D M; Green, J D; Najita, J; Chen, C H

    2007-01-01

    We present the mid-infrared spectrum, obtained with the Spitzer Infrared Spectrograph (IRS), of HD 98800, a quadruple star system located in the 10-Myr-old TW Hydrae association. It has a known mid-infrared excess that arises from a circumbinary disk around the B components of the system. The IRS spectrum confirms that the disk around HD 98800 B displays no excess emission below about 5.5 micron, implying an optically thick disk wall at 5.9 AU and an inner, cleared-out region; however, some optically thin dust, consisting mainly of 3-micron-sized silicate dust grains, orbits the binary in a ring between 1.5 and 2 AU. The peculiar structure and apparent lack of gas in the HD 98800 B disk suggests that this system is likely already at the debris disks stage, with a tidally truncated circumbinary disk of larger dust particles and an inner, second-generation dust ring, possibly held up by the resonances of a planet. The unusually large infrared excess can be explained by gravitational perturbations of the Aa+Ab p...

  9. The origin of the excess transit absorption in the HD 189733 system: planet or star?

    Science.gov (United States)

    Barnes, J. R.; Haswell, C. A.; Staab, D.; Anglada-Escudé, G.

    2016-10-01

    We have detected excess absorption in the emission cores of Ca II H&K during transits of HD 189733b for the first time. Using observations of three transits, we investigate the origin of the absorption, which is also seen in Hα and the Na I D lines. Applying differential spectrophotometry methods to the Ca II H and Ca II K lines combined, using respective passband widths of Δλ = 0.4 and 0.6 Å yields excess absorption of td = 0.0074 ± 0.0044 (1.7σ; Transit 1) and 0.0214 ± 0.0022 (9.8σ; Transit 2). Similarly, we detect excess Hα absorption in a passband of width Δλ = 0.7 Å, with td = 0.0084 ± 0.0016 (5.2σ) and 0.0121 ± 0.0012 (9.9σ). For both lines, Transit 2 is thus significantly deeper. Combining all three transits for the Na I D lines yields excess absorption of td = 0.0041 ± 0.0006 (6.5σ). By considering the time series observations of each line, we find that the excess apparent absorption is best recovered in the stellar reference frame. These findings lead us to postulate that the main contribution to the excess transit absorption in the differential light curves arises because the normalizing continuum bands form in the photosphere, whereas the line cores contain a chromospheric component. We cannot rule out that part of the excess absorption signature arises from the planetary atmosphere, but we present evidence which casts doubt on recent claims to have detected wind motions in the planet's atmosphere in these data.

  10. Evolution of Accreting Binary Systems on the Spin-up Line

    CERN Document Server

    Taani, Ali; Khasawneh, Awni

    2014-01-01

    The measured characteristics of binary pulsars provide valuable insights into the evolution of these systems. We study the aspects of binary evolution particularly relevant to binary Millisecond Pulsars (MSPs), and the formation of close binaries involving degenerate stars through a spin-evolution diagram (spin-up line). For this task, we use a wide variety of binaries, including those with compact components that observed in different energy bands, which we analyze them according to the spin-up line. Their formation and evolution over timescales of binary evolution models are investigated in order to grab any constraint on their evolution, and to estimate the masses of neutron stars with different mass-transfer histories.

  11. The third post-Newtonian gravitational waveforms for compact binary systems in general orbits: instantaneous terms

    CERN Document Server

    Mishra, Chandra Kant; Iyer, Bala R

    2015-01-01

    We compute the instantaneous contributions to the spherical harmonic modes of gravitational waveforms from compact binary systems in general orbits up to the third post-Newtonian order. We further extend these results for compact binaries in quasi-elliptical orbits using the 3PN quasi-Keplerian representation of the conserved dynamics of compact binaries in eccentric orbits. Using the multipolar post-Minkowskian formalism, starting from the different mass and current type multipole moments, we compute the spin weighted spherical harmonic decomposition of the instantaneous part of the gravitational waveform. These are terms which are functions of the retarded time and do not depend on the history of the binary evolution. Together with the hereditary part, which depends on the binary's dynamical history, these waveforms form the basis for construction of accurate templates for the detection of gravitational wave signals from binaries moving in quasi-elliptical orbits.

  12. On the Physical Processes in Contact Binary Systems

    Institute of Scientific and Technical Information of China (English)

    Run-Qian Huang; Han-Feng Song; Shao-Lan Bi

    2007-01-01

    Three important physical processes occurring in contact binary systems are studied.The first one is the effect of spin, orbital rotation and tide on the structure of the components,which includes also the effect of meridian circulation on the mixing of the chemical elements in the components. The second one is the mass and energy exchange between the components.To describe the energy exchange, a new approach is introduced based on the understanding that the exchange is due to the release of the potential, kinetic and thermal energy of the exchanged mass. The third is the loss of mass and angular momentum through the outer Lagrangian point. The rate of mass loss and the angular momentum carried away by the lost mass are discussed. To show the effects of these processes, we follow the evolution of a binary system consisting of a 12M⊙ and a 5M⊙ star with mass exchange between the components and mass loss via the outer Lagrangian point, both with and without considering the effects of rotation and tide. The result shows that the effect of rotation and tide advances the start of the semi-detached and the contact phases, and delays the end of the hydrogen-burning phase of the primary. Furthermore, it can change not only the occurrence of mass and angular momentum loss via the outer Lagrangian point, but also the contact or semi-contact status of the system. Thus, this effect can result in the special phenomenon of short-term variations occurring over a slow increase of the orbital period. The occurrence of mass and angular momentum loss via the outer Lagrangian point can affect the orbital period of the system significantly, but this process can be influenced, even suppressed out by the effect of rotation and tide. The mass and energy exchange occurs in the common envelope. The net result of the mass exchange process is a mass transfer from the primary to the secondary during the whole contact phase.

  13. The Effect of Novel Binary Accelerator System on Properties of Vulcanized Natural Rubber

    Directory of Open Access Journals (Sweden)

    Moez Kamoun

    2009-01-01

    Full Text Available The mechanical properties, curing characteristics, and swelling behaviour of vulcanized natural rubber with a novel binary accelerator system are investigated. Results indicate that the mechanical properties were improved. Crosslinking density of vulcanized natural rubber was measured by equilibrium swelling method. As a result, the new binary accelerator was found to be able to improve both cure rate and crosslinking density. Using the numerical analysis of test interaction between binary accelerator and operational modelling of vulcanization-factors experiments, it can be concluded that the interaction (Cystine, N-cyclohexyl-2-benzothiazyl sulfenamide was significant and the optimum value of binary accelerator was suggested, respectively, at levels 0 and +1.

  14. An Accretion Disc Model For Eclipsing Binary System: AV Del

    CERN Document Server

    Ghoreyshi, Sayyed Mohammad Reza; Salehi, Fatemeh

    2008-01-01

    We investigate the light and radial-velocity curves of the eclipsing binary AV Del. Using the most new version of Wilson & Van Hamme (2003) code, the absolute elements, fundamental orbital and physical parameters of the system are determined. Then, using the new SHELLSPEC code, we study and present an accretion disc model for the system. We found AV Del is a semi-detached system which has an accretion disc around the primary star. By combining the radial-velocity and light curve analysis, we derive accurate absolute masses for the components of M1=1.449 Msun and M2 =0.687 Msun and radii of R1=2.61 Rsun and R2=4.21 Rsun as well as effective temperatures of T1=6000 K and T2= 4281 K for the primary and the secondary, respectively. Also, we derived a temperature of T=5700 K for the disc. Finally, our results are compared with those of previous authors.

  15. Phase equilibria in the neodymium-cadmium binary system.

    Science.gov (United States)

    Skołyszewska-Kühberger, Barbara; Reichmann, Thomas L; Ipser, Herbert

    2014-09-05

    The equilibrium phase diagram of the neodymium-cadmium system has been established by thermal, metallographic and X-ray analysis based on a study of 70 alloys. The system contains three congruently melting intermetallic compounds, i.e. NdCd (1040 °C), NdCd2 (995 °C), Nd11Cd45 (855 °C), and four incongruently melting compounds NdCd3 (860 °C), Nd13Cd58 (740 °C), NdCd6 (655 °C) and NdCd11 (520 °C). Four eutectic reactions are found in this binary system, i.e. at ∼25 at.% Cd and 770 °C, at 58 at.% Cd and 955 °C, at 79 at.% Cd and 850 °C, and very close to pure Cd at 318 °C, as well as one eutectoid reaction at ∼15 at.% Cd and 500 °C. The solid solubility of Nd in Cd is negligible. Dilatometric curves were recorded for three Nd-Cd compositions up to 4 at.% Cd, to accurately determine phase transitions between the solid solutions of Cd in the low- and high-temperature modification of Nd.

  16. Phase equilibria in the neodymium–cadmium binary system

    Science.gov (United States)

    Skołyszewska-Kühberger, Barbara; Reichmann, Thomas L.; Ipser, Herbert

    2014-01-01

    The equilibrium phase diagram of the neodymium–cadmium system has been established by thermal, metallographic and X-ray analysis based on a study of 70 alloys. The system contains three congruently melting intermetallic compounds, i.e. NdCd (1040 °C), NdCd2 (995 °C), Nd11Cd45 (855 °C), and four incongruently melting compounds NdCd3 (860 °C), Nd13Cd58 (740 °C), NdCd6 (655 °C) and NdCd11 (520 °C). Four eutectic reactions are found in this binary system, i.e. at ∼25 at.% Cd and 770 °C, at 58 at.% Cd and 955 °C, at 79 at.% Cd and 850 °C, and very close to pure Cd at 318 °C, as well as one eutectoid reaction at ∼15 at.% Cd and 500 °C. The solid solubility of Nd in Cd is negligible. Dilatometric curves were recorded for three Nd–Cd compositions up to 4 at.% Cd, to accurately determine phase transitions between the solid solutions of Cd in the low- and high-temperature modification of Nd. PMID:25197164

  17. THE ROTATION PERIOD OF HD-77581 (VELA X-1)

    NARCIS (Netherlands)

    ZUIDERWIJK, EJ

    1995-01-01

    The rotation period of HD 77581, supergiant primary in the X-ray binary Vela X-1, is determined from an analysis of selected absorption line profiles. The rotation rate determined from He I line profiles is 0.67 +/- 0.04 times that of the binary angular velocity, corresponding to a rotation velocity

  18. Runaway Massive Binaries and Cluster Ejection Scenarios

    CERN Document Server

    McSwain, M V; Boyajian, T S; Grundstrom, E D; Roberts, M S E; Ransom, Scott M.; Boyajian, Tabetha S.; Grundstrom, Erika D.

    2006-01-01

    The production of runaway massive binaries offers key insights into the evolution of close binary stars and open clusters. The stars HD 14633 and HD 15137 are rare examples of such runaway systems, and in this work we investigate the mechanism by which they were ejected from their parent open cluster, NGC 654. We discuss observational characteristics that can be used to distinguish supernova ejected systems from those ejected by dynamical interactions, and we present the results of a new radio pulsar search of these systems as well as estimates of their predicted X-ray flux assuming that each binary contains a compact object. Since neither pulsars nor X-ray emission are observed in these systems, we cannot conclude that these binaries contain compact companions. We also consider whether they may have been ejected by dynamical interactions in the dense environment where they formed, and our simulations of four-body interactions suggest that a dynamical origin is possible but unlikely. We recommend further X-ra...

  19. Binary polypeptide system for permanent and oriented protein immobilization

    Directory of Open Access Journals (Sweden)

    Bailes Julian

    2010-05-01

    Full Text Available Abstract Background Many techniques in molecular biology, clinical diagnostics and biotechnology rely on binary affinity tags. The existing tags are based on either small molecules (e.g., biotin/streptavidin or glutathione/GST or peptide tags (FLAG, Myc, HA, Strep-tag and His-tag. Among these, the biotin-streptavidin system is most popular due to the nearly irreversible interaction of biotin with the tetrameric protein, streptavidin. The major drawback of the stable biotin-streptavidin system, however, is that neither of the two tags can be added to a protein of interest via recombinant means (except for the Strep-tag case leading to the requirement for chemical coupling. Results Here we report a new immobilization system which utilizes two monomeric polypeptides which self-assemble to produce non-covalent yet nearly irreversible complex which is stable in strong detergents, chaotropic agents, as well as in acids and alkali. Our system is based on the core region of the tetra-helical bundle known as the SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor complex. This irreversible protein attachment system (IPAS uses either a shortened syntaxin helix and fused SNAP25-synaptobrevin or a fused syntaxin-synaptobrevin and SNAP25 allowing a two-component system suitable for recombinant protein tagging, capture and immobilization. We also show that IPAS is suitable for use with traditional beads and chromatography, planar surfaces and Biacore, gold nanoparticles and for protein-protein interaction in solution. Conclusions IPAS offers an alternative to chemical cross-linking, streptavidin-biotin system and to traditional peptide affinity tags and can be used for a wide range of applications in nanotechnology and molecular sciences.

  20. The dynamical importance of binary systems in young massive star clusters

    CERN Document Server

    de Grijs, Richard; Geller, Aaron M

    2015-01-01

    Characterization of the binary fractions in star clusters is of fundamental importance for many fields in astrophysics. Observations indicate that the majority of stars are found in binary systems, while most stars with masses greater than $0.5 M_\\odot$ are formed in star clusters. In addition, since binaries are on average more massive than single stars, in resolved star clusters these systems are thought to be good tracers of (dynamical) mass segregation. Over time, dynamical evolution through two-body relaxation will cause the most massive objects to migrate to the cluster center, while the relatively lower-mass objects remain in or migrate to orbits at greater radii. This process will globally dominate a cluster's stellar distribution. However, close encounters involving binary systems may disrupt `soft' binaries. This process will occur more frequently in a cluster's central, dense region than in its periphery, which may mask the effects of mass segregation. Using high resolution Hubble Space Telescope o...

  1. Escape dynamics in a binary system of interacting galaxies

    CERN Document Server

    Zotos, Euaggelos E

    2016-01-01

    The escape dynamics in an analytical gravitational model which describes the motion of stars in a binary system of interacting dwarf spheroidal galaxies is investigated in detail. We conduct a numerical analysis distinguishing between regular and chaotic orbits as well as between trapped and escaping orbits, considering only unbounded motion for several energy levels. In order to distinguish safely and with certainty between ordered and chaotic motion, we apply the Smaller ALingment Index (SALI) method. It is of particular interest to locate the escape basins through the openings around the collinear Lagrangian points $L_1$ and $L_2$ and relate them with the corresponding spatial distribution of the escape times of the orbits. Our exploration takes place both in the configuration $(x,y)$ and in the phase $(x,\\dot{x})$ space in order to elucidate the escape process as well as the overall orbital properties of the galactic system. Our numerical analysis reveals the strong dependence of the properties of the con...

  2. MILLIONS OF MULTIPLES: DETECTING AND CHARACTERIZING CLOSE-SEPARATION BINARY SYSTEMS IN SYNOPTIC SKY SURVEYS

    Energy Technology Data Exchange (ETDEWEB)

    Terziev, Emil; Law, Nicholas M. [Dunlap Institute for Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, Ontario M5S 3H4 (Canada); Arcavi, Iair [Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot 76100 (Israel); Baranec, Christoph; Bui, Khanh; Dekany, Richard G.; Kulkarni, S. R.; Riddle, Reed; Tendulkar, Shriharsh P. [Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Bloom, Joshua S. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Burse, Mahesh P.; Chorida, Pravin; Das, H. K.; Punnadi, Sujit; Ramaprakash, A. N. [Inter-University Centre for Astronomy and Astrophysics, Ganeshkhind, Pune 411007 (India); Kraus, Adam L. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Nugent, Peter [Computational Cosmology Center, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Ofek, Eran O. [Benoziyo Center for Astrophysics, Weizmann Institute of Science, 76100 Rehovot (Israel); Sullivan, Mark, E-mail: emil.terziev@utoronto.ca [Department of Physics (Astrophysics), University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom)

    2013-06-01

    The direct detection of binary systems in wide-field surveys is limited by the size of the stars' point-spread functions (PSFs). A search for elongated objects can find closer companions, but is limited by the precision to which the PSF shape can be calibrated for individual stars. Based on a technique from weak-lensing analysis, we have developed the BinaryFinder algorithm to search for close binaries by using precision measurements of PSF ellipticity across wide-field survey images. We show that the algorithm is capable of reliably detecting binary systems down to Almost-Equal-To 1/5 of the seeing limit, and can directly measure the systems' position angles, separations, and contrast ratios. To verify the algorithm's performance we evaluated 100,000 objects in Palomar Transient Factory (PTF) wide-field-survey data for signs of binarity, and then used the Robo-AO robotic laser adaptive optics system to verify the parameters of 44 high-confidence targets. We show that BinaryFinder correctly predicts the presence of close companions with a <11% false-positive rate, measures the detected binaries' position angles within 1 Degree-Sign to 4 Degree-Sign (depending on signal-to-noise ratio and separation), and separations within 25%, and weakly constrains their contrast ratios. When applied to the full PTF data set, we estimate that BinaryFinder will discover and characterize {approx}450,000 physically associated binary systems with separations <2 arcsec and magnitudes brighter than m{sub R} = 18. New wide-field synoptic surveys with high sensitivity and sub-arcsecond angular resolution, such as LSST, will allow BinaryFinder to reliably detect millions of very faint binary systems with separations as small as 0.1 arcsec.

  3. The photometric investigation of the newly discovered W UMa type binary system GSC 03122-02426

    Science.gov (United States)

    Zhou, X.; Qian, S.-B.; He, J.-J.; Zhang, J.; Zhang, B.

    2016-10-01

    The B V Rc Ic bands light curves of the newly discovered binary system GSC 03122-02426 are obtained and analyzed using the Wilson-Devinney (W-D) code. The solutions suggest that the mass ratio of the binary system is q = 2.70 and the less massive component is 422 K hotter than the more massive one. We conclude that GSC 03122-02426 is a W-subtype shallow contact (with a contact degree of f = 15.3 %) binary system. It may be a newly formed contact binary system which is just under geometrical contact and will evolve to be a thermal contact binary system. The high orbital inclination (i = 81 .6∘) implies that GSC 03122-02426 is a total eclipsing binary system and the photometric parameters obtained by us are quite reliable. We also estimate the absolute physical parameters of the two components in GSC 03122-02426, which will provide fundamental information for the research of contact binary systems. The formation and evolutionary scenario of GSC 03122-02426 is discussed.

  4. The photometric investigation of the newly discovered W UMa type binary system GSC 03122-02426

    CERN Document Server

    Zhou, X; He, J -J; Zhang, J; Zhang, B

    2016-01-01

    The $B$ $V$ $R_c$ $I_c$ bands light curves of the newly discovered binary system \\astrobj{GSC 03122-02426} are obtained and analyzed using the Wilson-Devinney (W-D) code. The solutions suggest that the mass ratio of the binary system is $q = 2.70$ and the less massive component is $422K$ hotter than the more massive one. We conclude that \\astrobj{GSC 03122-02426} is a W-subtype shallow contact (with a contact degree of $f = 15.3\\,\\%$) binary system. It may be a newly formed contact binary system which is just under geometrical contact and will evolve to be a thermal contact binary system. The high orbital inclination ($i = 81.6^{\\circ}$) implies that \\astrobj{GSC 03122-02426} is a total eclipsing binary system and the photometric parameters obtained by us are quite reliable. We also estimate the absolute physical parameters of the two components in \\astrobj{GSC 03122-02426}, which will provide fundamental information for the research of contact binary systems. The formation and evolutionary scenario of \\astro...

  5. Design Points of HD Simulation Remote Video Conferencing System%高清仿真远程视频会议系统的设计要点

    Institute of Scientific and Technical Information of China (English)

    任亚武; 赵雨农; 王青

    2014-01-01

    本文以RPX极致远真系统为基础,详细阐述了高清仿真远程视频会议系统的技术特点、设备组成以及系统设计要点。%Based on the RPX extreme far real system, the essay elaborates the technical characteristics, equipment constitutes and system design of HD simulation remote video conferencing system.

  6. The GAPS Programme with HARPS-N@TNG XII: Characterization of the planetary system around HD108874

    CERN Document Server

    Benatti, S; Damasso, M; Malavolta, L; Lanza, A F; Biazzo, K; Bonomo, A S; Claudi, R U; Marzari, F; Poretti, E; Gratton, R; Micela, G; Pagano, I; Piotto, G; Sozzetti, A; Boccato, C; Cosentino, R; Covino, E; Maggio, A; Molinari, E; Smareglia, R; Affer, L; Andreuzzi, G; Bignamini, A; Borsa, F; di Fabrizio, L; Esposito, M; Fiorenzano, A Martinez; Messina, S; Giacobbe, P; Harutyunyan, A; Knapic, C; Maldonado, J; Masiero, S; Nascimbeni, V; Pedani, M; Rainer, M; Scandariato, G; Silvotti, R

    2016-01-01

    In order to understand the observed physical and orbital diversity of extrasolar planetary systems, a full investigation of these objects and of their host stars is necessary. Within this field, one of the main purposes of the GAPS observing project with HARPS-N@TNG is to provide a more detailed characterisation of already known systems. In this framework we monitored the star, hosting two giant planets, HD108874, with HARPS-N for three years in order to refine the orbits, to improve the dynamical study and to search for additional low-mass planets in close orbits. We subtracted the radial velocity (RV) signal due to the known outer planets, finding a clear modulation of 40.2 d period. We analysed the correlation between RV residuals and the activity indicators and modelled the magnetic activity with a dedicated code. Our analysis suggests that the 40.2 d periodicity is a signature of the rotation period of the star. A refined orbital solution is provided, revealing that the system is close to a mean motion r...

  7. Magnetised winds in single and binary star systems

    Science.gov (United States)

    Johnstone, Colin

    2016-07-01

    Stellar winds are fundamentally important for the stellar magnetic activity evolution and for the immediate environment surrounding their host stars. Ionised winds travel at hundreds of km/s, impacting planets and clearing out large regions around the stars called astropheres. Winds influence planets in many ways: for example, by compressing the magnetosphere and picking up atmospheric particles, they can cause significant erosion of a planetary atmosphere. By removing angular momentum, winds cause the rotation rates of stars to decrease as they age. This causes the star's magnetic dynamo to decay, leading to a significant decay in the star's levels of X-ray and extreme ultraviolet emission. Despite their importance, little is currently known about the winds of other Sun-like stars. Their small mass fluxes have meant that no direct detections have so far been possible. What is currently known has either been learned indirectly or through analogies with the solar wind. In this talk, I will review what is known about the properties and evolution of the winds of other Sun-like stars. I will also review wind dynamics in binary star systems, where the winds from both stars impact each other, leading to shocks and compression regions.

  8. Resolving the HD 100546 Protoplanetary System with the Gemini Planet Imager: Evidence for Multiple Forming, Accreting Planets

    CERN Document Server

    Currie, Thayne; Brittain, Sean; Grady, Carol; Burrows, Adam; Muto, Takayuki; Kenyon, Scott J; Kuchner, Marc J

    2015-01-01

    We report Gemini Planet Imager H band high-contrast imaging/integral field spectroscopy and polarimetry of the HD 100546, a 10 $Myr$-old early-type star recently confirmed to host a thermal infrared bright (super)jovian protoplanet at wide separation, HD 100546 b. We resolve the inner disk cavity in polarized light, recover the thermal-infrared (IR) bright arm, and identify one additional spiral arm. We easily recover HD 100546 b and show that much of its emission originates an unresolved, point source. HD 100546 b likely has extremely red infrared colors compared to field brown dwarfs, qualitatively similar to young cloudy superjovian planets, however, these colors may instead indicate that HD 100546 b is still accreting material from a circumplanetary disk. Additionally, we identify a second point source-like peak at $r_{proj}$ $\\sim$ 13 AU, located just interior to or at inner disk wall consistent with being a 10--20 $M_{J}$ candidate second protoplanet-- "HD 100546 c" -- and lying within a weakly polarize...

  9. The two-dimensional alternative binary L-J system: liquid-gas phase diagram

    Institute of Scientific and Technical Information of China (English)

    张陟; 陈立溁

    2003-01-01

    A two-dimensional (2D) binary system without considering the Lennard-Jones (L-J) potential has been studied by using the Collins model. In this paper, we introduce the L-J potential into the 2D binary system and consider the existence of the holes that are called the "molecular fraction". The liquid-gas phase diagram of the 2D alternative binary L-J system is obtained. The results are quite analogous to the behaviour of 3D substances.

  10. Cancer-specific binary expression system activated in mice by bacteriophage HK022 Integrase.

    Science.gov (United States)

    Elias, Amer; Spector, Itay; Sogolovsky-Bard, Ilana; Gritsenko, Natalia; Rask, Lene; Mainbakh, Yuli; Zilberstein, Yael; Yagil, Ezra; Kolot, Mikhail

    2016-04-27

    Binary systems based on site-specific recombination have been used for tumor specific transcription targeting of suicide genes in animal models. In these binary systems a site specific recombinase or integrase that is expressed from a tumor specific promoter drives tumor specific expression of a cytotoxic gene. In the present study we developed a new cancer specific binary expression system activated by the Integrase (Int) of the lambdoid phage HK022. We demonstrate the validity of this system by the specific expression of a luciferase (luc) reporter in human embryonic kidney 293T (HEK293T) cells and in a lung cancer mouse model. Due to the absence viral vectors and of cytotoxicity the Int based binary system offers advantages over previously described counterparts and may therefore be developed into a safer cancer cell killing system.

  11. A comparative study on invasion, survival, modulation of oxidative burst, and nitric oxide responses of macrophages (HD11), and systemic infection in chickens by prevalent poultry Salmonella serovars.

    Science.gov (United States)

    He, Haiqi; Genovese, Kenneth J; Swaggerty, Christina L; Nisbet, David J; Kogut, Michael H

    2012-12-01

    Poultry is a major reservoir for foodborne Salmonella serovars. Salmonella Typhimurium, Salmonella Enteritidis, Salmonella Heidelberg, Salmonella Kentucky, and Salmonella Senftenberg are the most prevalent serovars in U.S. poultry. Information concerning the interactions between different Salmonella species and host cells in poultry is lacking. In the present study, the above mentioned Salmonella serovars were examined for invasion, intracellular survival, and their ability to modulate oxidative burst and nitric oxide (NO) responses in chicken macrophage HD11 cells. All Salmonella serovars demonstrated similar capacity to invade HD11 cells. At 24 h post-infection, a 36-43% reduction of intracellular bacteria, in log(10)(CFU), was observed for Salmonella Typhimurium, Salmonella Heidelberg, Salmonella Kentucky, and Salmonella Senftenberg, whereas a significantly lower reduction (16%) was observed for Salmonella Enteritidis, indicating its higher resistance to the killing by HD11 cells. Production of NO was completely diminished in HD11 cells infected with Salmonella Typhimurium and Salmonella Enteritidis, but remained intact when infected with Salmonella Heidelberg, Salmonella Kentucky, and Salmonella Senftenberg. Phorbol myristate acetate-stimulated oxidative burst in HD11 cells was greatly impaired after infection by each of the five serovars. When newly hatched chickens were challenged orally, a high rate (86-98%) of systemic infection (Salmonella positive in liver/spleen) was observed in birds challenged with Salmonella Typhimurium, Salmonella Enteritidis, Salmonella Heidelberg, and Salmonella Kentucky, while only 14% of the birds were Salmonella Senftenberg positive. However, there was no direct correlation between systemic infection and in vitro differential intracellular survival and modulation of NO response among the tested serovars.

  12. FPGA-Based HD Camera System for the Micropositioning of Biomedical Micro-Objects Using a Contactless Micro-Conveyor

    Directory of Open Access Journals (Sweden)

    Elmar Yusifli

    2017-03-01

    Full Text Available With recent advancements, micro-object contactless conveyers are becoming an essential part of the biomedical sector. They help avoid any infection and damage that can occur due to external contact. In this context, a smart micro-conveyor is devised. It is a Field Programmable Gate Array (FPGA-based system that employs a smart surface for conveyance along with an OmniVision complementary metal-oxide-semiconductor (CMOS HD camera for micro-object position detection and tracking. A specific FPGA-based hardware design and VHSIC (Very High Speed Integrated Circuit Hardware Description Language (VHDL implementation are realized. It is done without employing any Nios processor or System on a Programmable Chip (SOPC builder based Central Processing Unit (CPU core. It keeps the system efficient in terms of resource utilization and power consumption. The micro-object positioning status is captured with an embedded FPGA-based camera driver and it is communicated to the Image Processing, Decision Making and Command (IPDC module. The IPDC is programmed in C++ and can run on a Personal Computer (PC or on any appropriate embedded system. The IPDC decisions are sent back to the FPGA, which pilots the smart surface accordingly. In this way, an automated closed-loop system is employed to convey the micro-object towards a desired location. The devised system architecture and implementation principle is described. Its functionality is also verified. Results have confirmed the proper functionality of the developed system, along with its outperformance compared to other solutions.

  13. Treating dynamical stability as an observable: a 5:2 MMR configuration for the extrasolar system HD 181433

    CERN Document Server

    Campanella, Giammarco

    2011-01-01

    The three-planet extrasolar system of HD 181433 has been detected with HARPS. The best-fit solution, announced by the discovery team, describes a highly unstable, self-disrupting configuration. In fact, a narrow observational window, only partially covering the longest orbital period, can lead to solutions representing unrealistic scenarios. Taking into account the dynamical stability as an additional observable while interpreting the RV data, we can analyse the phase space in a neighbourhood of the statistically best-fit and derive dynamically stable configurations that reproduce the observed RV signal. Our Newtonian stable best-fit model is capable of surviving for at least 250 Myrs. The two giant companions are found to be locked in the 5:2 MMR as Jupiter and Saturn in the Solar System. This mechanism does not allow close encounters even in case of highly eccentric orbits. Moreover, planets c and d are located in regions spanned by many other strong low-order MMRs. We study the dynamics of some plausible s...

  14. Understanding the Relationship Between Observations and Stellar Parameters in an Eclipsing Binary System

    CERN Document Server

    Creevey, O L; Jiménez-Reyes, S J; Belmonte, J A

    2006-01-01

    We would like to investigate the information contained in our observations and to what extent each of them contributes individually to constraining the physical parameters of the system we are investigating. To do this, we present a study involving the technique of Singular Value Decomposition using as a simple example a detached eclipsing binary system. We intend to apply an extension of this technique to asteroseismic measurements of Delta~Scuti stars that are members of eclipsing binary systems.

  15. Analytic calculation of formation enthalpies directly from interatomic potentials for binary and ternary refractory metal systems

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    An analytic method is proposed to calculate the formation enthalpy directly from empirical n-body potential and applied to the binary and ternary systems consisting of the refractory metals Mo, Nb, Ta and W. It turns out that the calculated enthalpies are in overall agreement with experimental observations and some other theoretical calculations. Interestingly, it shows that the formation enthalpies of the ternary systems are significantly affected by those of the constituent binary systems.

  16. KELT-2Ab: A Hot Jupiter Transiting the Bright (V=8.77) Primary Star of a Binary System

    CERN Document Server

    Beatty, Thomas G; Siverd, Robert J; Eastman, Jason D; Bieryla, Allyson; Latham, David W; Buchhave, Lars A; Jensen, Eric L N; Manner, Mark; Stassun, Keivan G; Gaudi, B Scott; Berlind, Perry; Calkins, Michael L; Collins, Karen; DePoy, Darren L; Esquerdo, Gilbert A; Fulton, Benjamin J; Fűrész, Gábor; Geary, John C; Gould, Andrew; Hebb, Leslie; Kielkopf, John F; Marshall, Jennifer L; Pogge, Richard; Stanek, K Z; Stefanik, Robert P; Street, Rachel; Szentgyorgyi, Andrew H; Trueblood, Mark; Trueblood, Patricia; Stutz, Amelia M

    2012-01-01

    We report the discovery of KELT-2Ab, a hot Jupiter transiting the bright (V=8.77) primary star of the HD 42176 binary system. The host is a slightly evolved late F-star likely in the very short-lived "blue-hook" stage of evolution, with $\\teff=6151\\pm50{\\rm K}$, $\\log{g_*}=4.030_{-0.028}^{+0.013}$ and $\\feh=-0.018\\pm0.069$. The inferred stellar mass is $M_*=1.308_{-0.025}^{+0.028}$\\msun\\ and the star has a relatively large radius of $R_*=1.828_{-0.034}^{+0.070}$\\rsun. The planet is a typical hot Jupiter with period $4.113791\\pm0.00001$ days and a mass of $M_P=1.522\\pm0.078$\\mj\\ and radius of $R_P=1.286_{-0.047}^{+0.065}$\\rj. This is mildly inflated as compared to models of irradiated giant planets at the $\\sim$4 Gyr age of the system. KELT-2A is the third brightest star with a transiting planet identified by ground-based transit surveys, and the ninth brightest star overall with a transiting planet. KELT-2Ab's mass and radius are unique among the subset of planets with $V<9$ host stars, and therefore incre...

  17. Near-Infrared Polarimetry of the GG Tauri A Binary System

    CERN Document Server

    Itoh, Yoichi; Kudo, Tomoyuki; Kusakabe, Nobuhiko; Hashimoto, Jun; Abe, Lyu; Brandner, Wolfgang; Brandt, Timothy D; Carson, Joseph C; Egner, Sebastian; Feldt, Markus; Grady, Carol A; Guyon, Olivier; Hayano, Yutaka; Hayashi, Masahiko; Hayashi, Saeko S; Henning, Thomas; Hodapp, Klaus W; Ishii, Miki; Iye, Masanori; Janson, Markus; Kandori, Ryo; Knapp, Gillian R; Kuzuhara, Masayuki; Kwon, Jungmi; Matsuo, Taro; McElwain, Michael W; Miyama, Shoken; Morino, Jun-Ichi; Moro-Martin, Amaya; Nishimura, Tetsuo; Pyo, Tae-Soo; Serabyn, Eugene; Suenaga, Takuya; Suto, Hiroshi; Suzuki, Ryuji; Takahashi, Yasuhiro H; Takato, Naruhisa; Terada, Hiroshi; Thalmann, Christian; Tomono, Daigo; Turner, Edwin L; Watanabe, Makoto; Wisniewski, John; Yamada, Toru; Mayama, Satoshi; Currie, Thayne; Takami, Hideki; Usuda, Tomonori; Tamura, Motohide

    2015-01-01

    A high angular resolution near-infrared polarized-intensity image of the GG Tau A binary system was obtained with the Subaru Telescope. The image shows the circumbinary disk scattering the light from the central binary. The azimuthal profile of the polarized intensity of the circumbinary disk is roughly reproduced by a simple disk model with the Henyey-Greenstein function and the Rayleigh function, indicating small dust grains at the surface of the disk. Combined with a previous observation of the circumbinary disk, our image indicates that the gap structure in the circumbinary disk orbits anti-clockwise, while material in the disk orbit clockwise. We propose a shadow of material located between the central binary and the circumbinary disk. The separations and position angles of the stellar components of the binary in the past 20 years are consistent with the binary orbit with a = 33.4 AU and e = 0.34.

  18. Non-thermal radio emission from O-type stars. II. HD 167971

    CERN Document Server

    Blomme, R; Runacres, M C; Van Loo, S; Gunawan, D Y A S

    2006-01-01

    HD 167971 is a triple system consisting of a 3.3-day eclipsing binary (O5-8 V + O5-8 V) and an O8 supergiant. It is also a well known non-thermal radio emitter. We observed the radio emission of HD 167971 with the Very Large Array (VLA) and the Australia Telescope Compact Array (ATCA). By combining these data with VLA archive observations we constructed a radio lightcurve covering a 20-yr time-range. We searched for, but failed to find, the 3.3-day spectroscopic period of the binary in the radio data. This could be due to the absence of intrinsic synchrotron radiation at the colliding-wind region between the two components of the eclipsing binary, or due to the large amount of free-free absorption that blocks the synchrotron radiation. We are able to explain many of the observed characteristics of the radio data if the non-thermal emission is produced in a colliding-wind region between the supergiant and the combined winds of the binary. Furthermore, if the system is gravitationally bound, the orbital motion ...

  19. Review of candidates of binary systems with an RR Lyrae component

    CERN Document Server

    Skarka, Marek; Zejda, Miloslav; Mikulášek, Zdeněk

    2016-01-01

    We present an overview and current status of research on RR Lyrae stars in binary systems. In present days the number of binary candidates has steeply increased and suggested that multiple stellar systems with an RR Lyrae component is much higher than previously thought. We discuss the probability of their detection using various observing methods, compare recent results regarding selection effects, period distribution, proposed orbital parameters and the Blazhko effect.

  20. The 2D Alternative Binary L-J System: Solid-Liquid Phase Diagram

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhi; CHEN Li-Rong

    2002-01-01

    The Lennard-Jones potential is introduced into the Collins model and is generalized to the two-dimensionalalternative binary system. The Gibbs free energy of the binary system is calculated. According to the thermodynamicconditions of solid-liquid equilibrium, the "cigar-type" phase diagram and the phase diagram with a minimum areobtained. The results are quite analogous to the behavior of three-dimensional substances.

  1. LISA Astronomy of Double White Dwarf Binary Systems

    NARCIS (Netherlands)

    Stroeer, A.; Vecchio, A.; Nelemans, G.A.

    2005-01-01

    The Laser Interferometer Space Antenna (LISA) will provide us with the largest observational sample of (interacting) double white dwarf binaries, whose evolution is driven by the radiation reaction and other effects, such as tides and mass transfer. We show that, depending on the actual physical par

  2. Migration into a Companion's Trap: Disruption of Multiplanet Systems in Binaries

    CERN Document Server

    Touma, Jihad R

    2015-01-01

    Most exoplanetary systems in binary stars are of S--type, and consist of one or more planets orbiting a primary star with a wide binary stellar companion. Gravitational forcing of a single planet by a sufficiently inclined binary orbit can induce large amplitude oscillations of the planet's eccentricity and inclination through the Kozai-Lidov (KL) instability. KL cycling was invoked to explain: the large eccentricities of planetary orbits; the family of close--in hot Jupiters; and the retrograde planetary orbits in eccentric binary systems. However, several kinds of perturbations can quench the KL instability, by inducing fast periapse precessions which stabilize circular orbits of all inclinations: these could be a Jupiter--mass planet, a massive remnant disc or general relativistic precession. Indeed, mutual gravitational perturbations in multiplanet S--type systems can be strong enough to lend a certain dynamical rigidity to their orbital planes. Here we present a new and faster process that is driven by t...

  3. The Non-thermal Radio Emitter HD 93250 Resolved by Long Baseline Interferometry

    Science.gov (United States)

    Sana, H.; Le Bouquin, J.-B.; De Becker, M.; Berger, J.-P.; de Koter, A.; Mérand, A.

    2011-10-01

    As the brightest O-type X-ray source in the Carina nebula, HD 93250 (O4 III(fc)) is X-ray overluminous for its spectral type and has an unusually hard X-ray spectrum. Two different scenarios have been invoked to explain its X-ray properties: wind-wind interaction and magnetic wind confinement. Yet, HD 93250 shows absolutely constant radial velocities over timescales of years suggesting either a single star, a binary system seen pole-on view or a very long period, and/or highly eccentric system. Using the ESO Very Large Telescope Interferometer, we resolved HD 93250 as a close pair with similar components. We measured a near-infrared flux ratio of 0.8 ± 0.1 and a separation of (1.5 ± 0.2) × 10-3 arcsec. At the distance of Carina, this corresponds to a projected physical distance of 3.5 AU. While a quantitative investigation would require a full characterization of the orbit, the binary nature of HD 93250 allows us to qualitatively explain both its X-ray flux and hardness and its non-thermal radio emission in the framework of a colliding wind scenario. We also discuss various observational biases. We show that, due to line blending of two similar spectral components, HD 93250 could have a period as short as 1 to several years despite the lack of measurable radial velocity variations. Based on observations collected under program IDs 086.D-0586 and 386.D-0198 at the European Organisation for Astronomical Research in the Southern Hemisphere, Chile.

  4. RESOLVING THE HD 100546 PROTOPLANETARY SYSTEM WITH THE GEMINI PLANET IMAGER: EVIDENCE FOR MULTIPLE FORMING, ACCRETING PLANETS

    Energy Technology Data Exchange (ETDEWEB)

    Currie, Thayne [National Astronomical Observatory of Japan, Subaru Telescope (Japan); Cloutier, Ryan [Department of Astronomy and Astrophysics, University of Toronto, Toronto, ON (Canada); Brittain, Sean [Department of Physics and Astronomy, Clemson University, Clemson, SC (United States); Grady, Carol; Kuchner, Marc J. [Exoplanets and Stellar Astrophysics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD (United States); Burrows, Adam [Department of Astrophysics Sciences, Princeton University, Princeton, NJ (United States); Muto, Takayuki [Division of Liberal Arts, Kogakuin University, Tokyo (Japan); Kenyon, Scott J. [Smithsonian Astrophysical Observatory, Cambridge, MA (United States)

    2015-12-01

    We report Gemini Planet Imager H-band high-contrast imaging/integral field spectroscopy and polarimetry of the HD 100546, a 10 Myr old early-type star recently confirmed to host a thermal infrared (IR) bright (super-)Jovian protoplanet at wide separation, HD 100546 b. We resolve the inner disk cavity in polarized light, recover the thermal IR-bright arm, and identify one additional spiral arm. We easily recover HD 100546 b and show that much of its emission plausibly originates from an unresolved point source. The point-source component of HD 100546 b has extremely red IR colors compared to field brown dwarfs, qualitatively similar to young cloudy super-Jovian planets; however, these colors may instead indicate that HD 100546 b is still accreting material from a circumplanetary disk. Additionally, we identify a second point-source-like peak at r{sub proj} ∼ 14 AU, located just interior to or at the inner disk wall consistent with being a <10–20 M{sub J} candidate second protoplanet—“HD 100546 c”—and lying within a weakly polarized region of the disk but along an extension of the thermal IR-bright spiral arm. Alternatively, it is equally plausible that this feature is a weakly polarized but locally bright region of the inner disk wall. Astrometric monitoring of this feature over the next 2 years and emission line measurements could confirm its status as a protoplanet, rotating disk hot spot that is possibly a signpost of a protoplanet, or a stationary emission source from within the disk.

  5. Observations of VHE gamma-ray binaries with the MAGIC Telescopes

    CERN Document Server

    López-Oramas, A; Cortina, J; Hadasch, D; Herrero, A; Marcote, B; Munar-Adrover, P; Moldón, J; Paredes, J M; Ribas, I; Ribó, M; Torres, D; Casares, J; Rea, N

    2013-01-01

    Several binary systems, composed of a star and a compact object, have been detected in the GeV-TeV range. Several systems have been observed but only a handful of sources have shown emission at those energies. Here, we present the observations conducted by MAGIC of different {\\gamma}-ray binary systems. On one hand, we show the latest studies on the binary system LS I +61 303, which displays variability on different timescales. With the latest MAGIC observations, we will try to shed light on our understanding of this source, by presenting super-orbital and multi-wavelength studies. On the other hand, we show the observational results on the binary system HD 215227. This source has been proposed as a new {\\gamma}-ray binary for being spatially coincident with the gamma-ray source AGL J2241+4454 detected by AGILE at E >100 GeV.

  6. A Differential Abundance Analysis of HD219175 A and B

    Institute of Scientific and Technical Information of China (English)

    Hua-Wei Zhang; Gang Zhao

    2005-01-01

    The abundances of the wide binary pair HD 219175 A and B are determined and compared using a line-by-line differential analysis. No evidence for difference has been found in the abundances of Fe, O, Na, Mg, Al, Si, K, Ca, Sc,Ti, V, Cr, Mn, Ni, Cu and Ba. Our results support a physical relation between the two components of HD 219175.

  7. Pro Tools HD

    CERN Document Server

    Camou, Edouard

    2013-01-01

    An easy-to-follow guide for using Pro Tools HD 11 effectively.This book is ideal for anyone who already uses ProTools and wants to learn more, or is new to Pro Tools HD and wants to use it effectively in their own audio workstations.

  8. An M-dwarf star in the transition disk of Herbig HD142527; Physical parameters and orbital elements

    CERN Document Server

    Lacour, S; Cheetham, A; Greenbaum, A; Pearce, T; Marino, S; Tuthill, P; Pueyo, L; Mamajek, E E; Girard, J H; Sivaramakrishnan, A; Bonnefoy, M; Baraffe, I; Chauvin, G; Olofsson, J; Juhasz, A; Benisty, M; Pott, J -U; Sicilia-Aguilar, A; Henning, T; Cardwell, A; Goodsell, S; Graham, J R; Hibon, P; Ingraham, P; Konopacky, Q; Macintosh, B; Oppenheimer, R; Perrin, M; Rantakyrö, F; Sadakuni, N; Thomas, S

    2015-01-01

    HD 142527A is one of the most studied Herbig Ae/Be stars with a transitional disk, as it has the largest imaged gap in any protoplanetary disk: the gas is cleared from 30 to 90 AU. The HD 142527 system is also unique in that it has a stellar companion with a small mass compared to the mass of the primary star. This factor of $\\approx20$ in mass ratio between the two objects makes this binary system different from any other YSO. The HD142527 system could therefore provides a valuable testbed for understanding the impact of a lower mass companion on disk structure. This low-mass stellar object may be responsible for both the gap and the dust trapping observed by ALMA at longer distances. We have observed this system with the NACO and GPI instruments using the aperture masking technique. Aperture masking is ideal for providing high dynamic range even at very small angular separations. We present here the SEDS for HD 142527A and B from the $R$ band up to the $M$ band as well as the orbital motion of HD 142527B ov...

  9. The eccentric short-period orbit of the supergiant fast X-ray transient HD 74194 (=LM Vel)

    CERN Document Server

    Gamen, R; Walborn, N R; Morrell, N I; Arias, J I; Apellániz, J Maíz; Sota, A; Alfaro, E J

    2015-01-01

    Aims. We present the first orbital solution for the O-type supergiant star HD 74194, which is the optical counterpart of the supergiant fast X-ray transient IGR J08408-4503. Methods. We measured the radial velocities in the optical spectrum of HD 74194, and we determined the orbital solution for the first time. We also analysed the complex H{\\alpha} profile. Results. HD 74194 is a binary system composed of an O-type supergiant and a compact object in a short-period ($P=9.5436\\pm0.0002$ d) and high-eccentricity ($e=0.63\\pm0.03$) orbit. The equivalent width of the H{\\alpha} line is not modulated entirely with the orbital period, but seems to vary in a superorbital period ($P=285\\pm10$ d) nearly 30 times longer than the orbital one.

  10. Estimating the Eutectic Composition of Simple Binary Alloy System Using Linear Geometry

    Directory of Open Access Journals (Sweden)

    Muhammed Olawale Hakeem AMUDA

    2008-06-01

    Full Text Available A simple linear equation was developed and applied to a hypothetical binary equilibrium diagram to evaluate the eutectic composition of the binary alloy system. Solution of the equations revealed that the eutectic composition of the case study Pb – Sn, Bi – Cd and Al – Si alloys are 39.89% Pb, 60.11% Sn, 58.01% Bi, 41.99% Cd and 90.94% Al, 9.06% Si respectively. These values are very close to experimental values. The percent deviation of analytical values from experimental values ranged between 2.87 and 5% for the three binary systems considered, except for Si – Al alloy in which the percent deviation for the silicon element was 22%.It is concluded that equation of straight line could be used to predict the eutectic composition of simple binary alloys within tolerable experimental deviation range of 2.5%.

  11. The Impact of Stellar Multiplicity on Planetary Systems, I.: The Ruinous Influence of Close Binary Companions

    CERN Document Server

    Kraus, Adam L; Huber, Daniel; Mann, Andrew W; Dupuy, Trent J

    2016-01-01

    The dynamical influence of binary companions is expected to profoundly influence planetary systems. However, the difficulty of identifying planets in binary systems has left the magnitude of this effect uncertain; despite numerous theoretical hurdles to their formation and survival, at least some binary systems clearly host planets. We present high-resolution imaging of 382 Kepler Objects of Interest (KOIs) obtained using adaptive-optics imaging and nonredundant aperture-mask interferometry (NRM) on the Keck-II telescope. Among the full sample of 506 candidate binary companions to KOIs, we super-resolve some binary systems to projected separations of 0.4; we instead only found 23 companions (a 4.6 sigma deficit), many of which must be wider pairs that are only close in projection. When the binary population is parametrized with a semimajor axis cutoff a_cut and a suppression factor inside that cutoff S_bin, we find with correlated uncertainties that inside a_cut = 47 +59/-23 AU, the planet occurrence rate in...

  12. Habitable-zone super-Earth candidate in a six-planet system around the K2.5V star HD 40307

    CERN Document Server

    Tuomi, Mikko; Gerlach, Enrico; Jones, Hugh R R; Reiners, Ansgar; Rivera, Eugenio J; Vogt, Steven S; Butler, R Paul

    2012-01-01

    The K2.5 dwarf HD 40307 has been reported to host three super-Earths. The system lacks massive planets and is therefore a potential candidate for having additional low-mass planetary companions. We re-derive Doppler measurements from public HARPS spectra of HD 40307 to confirm the significance of the reported signals using independent data analysis methods. We also investigate these measurements for additional low-amplitude signals. We used Bayesian analysis of our radial velocities to estimate the probability densities of different model parameters. We also estimated the relative probabilities of models with differing numbers of Keplerian signals and verified their significance using periodogram analyses. We investigated the relation of the detected signals with the chromospheric emission of the star. As previously reported for other objects, we found that radial velocity signals correlated with the S-index are strongly wavelength dependent. We identify two additional clear signals with periods of 34 and 51 ...

  13. Solid/liquid interfacial free energies in binary systems

    Science.gov (United States)

    Nason, D.; Tiller, W. A.

    1973-01-01

    Description of a semiquantitative technique for predicting the segregation characteristics of smooth interfaces between binary solid and liquid solutions in terms of readily available thermodynamic parameters of the bulk solutions. A lattice-liquid interfacial model and a pair-bonded regular solution model are employed in the treatment with an accommodation for liquid interfacial entropy. The method is used to calculate the interfacial segregation and the free energy of segregation for solid-liquid interfaces between binary solutions for the (111) boundary of fcc crystals. The zone of compositional transition across the interface is shown to be on the order of a few atomic layers in width, being moderately narrower for ideal solutions. The free energy of the segregated interface depends primarily upon the solid composition and the heats of fusion of the component atoms, the composition difference of the solutions, and the difference of the heats of mixing of the solutions.

  14. STELLAR ACTIVITY AND EXCLUSION OF THE OUTER PLANET IN THE HD 99492 SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Kane, Stephen R.; Thirumalachari, Badrinath; Hinkel, Natalie R. [Department of Physics and Astronomy, San Francisco State University, 1600 Holloway Avenue, San Francisco, CA 94132 (United States); Henry, Gregory W. [Center of Excellence in Information Systems, Tennessee State University, 3500 John A. Merritt Blvd., Box 9501, Nashville, TN 37209 (United States); Jensen, Eric L. N. [Dept of Physics and Astronomy, Swarthmore College, Swarthmore, PA 19081 (United States); Boyajian, Tabetha S.; Fischer, Debra A. [Department of Astronomy, Yale University, New Haven, CT 06511 (United States); Howard, Andrew W. [Institute for Astronomy, University of Hawaii, Honolulu, HI 96822 (United States); Isaacson, Howard T. [Astronomy Department, University of California, Berkeley, CA 94720 (United States); Wright, Jason T., E-mail: skane@sfsu.edu [Department of Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802 (United States)

    2016-03-20

    A historical problem for indirect exoplanet detection has been contending with the intrinsic variability of the host star. If the variability is periodic, it can easily mimic various exoplanet signatures, such as radial velocity (RV) variations that originate with the stellar surface rather than the presence of a planet. Here we present an update for the HD 99492 planetary system, using new RV and photometric measurements from the Transit Ephemeris Refinement and Monitoring Survey. Our extended time series and subsequent analyses of the Ca ii H and K emission lines show that the host star has an activity cycle of ∼13 years. The activity cycle correlates with the purported orbital period of the outer planet, the signature of which is thus likely due to the host star activity. We further include a revised Keplerian orbital solution for the remaining planet, along with a new transit ephemeris. Our transit-search observations were inconclusive.

  15. Properties and nature of Be stars 30. Reliable physical properties of a semi-detached B9.5e+G8III binary BR CMi = HD 61273 compared to those of other well studied semi-detached emission-line binaries

    CERN Document Server

    Harmanec, P; Nemravová, J A; Royer, F; Briot, D; North, P; Lampens, P; Frémat, Y; Yang, S; Božić, H; Kotková, L; Škoda, P; Šlechta, M; Korčáková, D; Wolf, M; Zasche, P

    2014-01-01

    Reliable determination of the basic physical properties of hot emission-line binaries with Roche-lobe filling secondaries is important for developing the theory of mass exchange in binaries. It is a very hard task, however, which is complicated by the presence of circumstellar matter in these systems. So far, only a small number of systems with accurate values of component masses, radii, and other properties are known. Here, we report the first detailed study of a new representative of this class of binaries, BR CMi, based on the analysis of radial velocities and multichannel photometry from several observatories, and compare its physical properties with those for other well-studied systems. BR CMi is an ellipsoidal variable seen under an intermediate orbital inclination of ~51 degrees, and it has an orbital period of 12.919059(15) d and a circular orbit. We used the disentangled component spectra to estimate the effective temperatures 9500(200) K and 4655(50) K by comparing them with model spectra. They corr...

  16. High Resolution Imaging of Very Low Mass Spectral Binaries: Three Resolved Systems and Detection of Orbital Motion in an L/T Transition Binary

    CERN Document Server

    Gagliuffi, Daniella C Bardalez; Burgasser, Adam J

    2015-01-01

    We present high resolution Laser Guide Star Adaptive Optics imaging of 43 late-M, L and T dwarf systems with Keck/NIRC2. These include 17 spectral binary candidates, systems whose spectra suggest the presence of a T dwarf secondary. We resolve three systems: 2MASS J1341$-$3052, SDSS J1511+0607 and SDSS J2052$-$1609; the first two are resolved for the first time. All three have projected separations $<8$ AU and estimated periods of $14-80$ years. We also report a preliminary orbit determination for SDSS J2052$-$1609 based on six epochs of resolved astrometry between 2005$-$2010. Among the 14 unresolved spectral binaries, 5 systems were confirmed binaries but remained unresolved, implying a minimum binary fraction of $47^{+12}_{-11}\\%$ for this sample. Our inability to resolve most of the spectral binaries, including the confirmed binaries, supports the hypothesis that a large fraction of very low mass systems have relatively small separations and are missed with direct imaging.

  17. The GAPS Programme with HARPS-N at TNG. XII. Characterization of the planetary system around HD 108874

    Science.gov (United States)

    Benatti, S.; Desidera, S.; Damasso, M.; Malavolta, L.; Lanza, A. F.; Biazzo, K.; Bonomo, A. S.; Claudi, R. U.; Marzari, F.; Poretti, E.; Gratton, R.; Micela, G.; Pagano, I.; Piotto, G.; Sozzetti, A.; Boccato, C.; Cosentino, R.; Covino, E.; Maggio, A.; Molinari, E.; Smareglia, R.; Affer, L.; Andreuzzi, G.; Bignamini, A.; Borsa, F.; di Fabrizio, L.; Esposito, M.; Martinez Fiorenzano, A.; Messina, S.; Giacobbe, P.; Harutyunyan, A.; Knapic, C.; Maldonado, J.; Masiero, S.; Nascimbeni, V.; Pedani, M.; Rainer, M.; Scandariato, G.; Silvotti, R.

    2017-03-01

    In order to understand the observed physical and orbital diversity of extrasolar planetary systems, a full investigation of these objects and of their host stars is necessary. Within this field, one of the main purposes of the GAPS observing project with HARPS-N at TNG is to provide a more detailed characterization of already known systems. In this framework we monitored the star, hosting two giant planets, HD 108874, with HARPS-N for three years in order to refine the orbits, to improve the dynamical study and to search for additional low-mass planets in close orbits. We subtracted the radial velocity (RV) signal due to the known outer planets, finding a clear modulation of 40.2 d period. We analysed the correlation between RV residuals and the activity indicators and modelled the magnetic activity with a dedicated code. Our analysis suggests that the 40.2 d periodicity is a signature of the rotation period of the star. A refined orbital solution is provided, revealing that the system is close to a mean motion resonance of about 9:2, in a stable configuration over 1 Gyr. Stable orbits for low-mass planets are limited to regions very close to the star or far from it. Our data exclude super-Earths with Msini ≳ 5M⊕ within 0.4 AU and objects with Msini ≳ 2M⊕ with orbital periods of a few days. Finally we put constraints on the habitable zone of the system, assuming the presence of an exomoon orbiting the inner giant planet. Based on observations made with the Italian Telescopio Nazionale Galileo (TNG) operated on the island of La Palma by the Fundación Galileo Galilei of the INAF at the Spanish Observatorio del Roque de los Muchachos of the IAC in the frame of the programme Global Architecture of Planetary Systems (GAPS).Table A.1 is also available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/599/A90

  18. The Planet in the HR 7162 Binary System Discovered by PHASES Astrometry

    Science.gov (United States)

    Muterspaugh, Matthew W.; Lane, B. F.; Konacki, M.; Burke, B. F.; Colavita, M. M.; Shao, M.; Hartkopf, W. I.; Boss, A. P.; O'Connell, J.; Fekel, F. C.; Wiktorowicz, S. J.

    2011-01-01

    The now-completed Palomar High-precision Astrometric Search for Exoplanet Systems (PHASES) used phase-referenced long-baseline interferometry to monitor 51 binary systems with 35 micro-arcsecond measurement precision, resulting in the high-confidence detection of a planet in the HR 7162 system. The 1.5 Jupiter mass planet is in a 2 AU orbit around one of the stars, whereas the binary itself has a separation of only 19 AU. Despite the close stellar companion, this configuration is expected to be stable, based on dynamic simulations. In the context of our solar system, this is analogous to a Jovian planet just outside of Mars' orbit, with a second star at the distance of Uranus. If this configuration were present during the period of planet formation, the complex gravitational environment created by the stars would seem to disrupt planet formation mechanisms that require long times to complete (thousands of years or more). While it is possible the arrangement resulted from the planet being formed in another environment (a single star or wider binary) after which the system reached its current state via dynamic interactions (star-planet exchange with a binary, or the binary orbit shrinking by interacting with a passing star), the frequency of such interactions is very low. Because the PHASES search only had the sensitivity to rule out Jovian mass companions in 11 of our 51 systems, yet one such system was found, the result indicates either extreme luck or that there is a high frequency of 20 AU binaries hosting planets. The latter interpretation is supported by previous detections of planets in 5-6 additional 20 AU binaries in other surveys (though with less control over the statistics for determining frequency of occurrence). Thus, there is observational support suggesting that a mechanism for rapid Jovian planet formation occurs in nature.

  19. Thermodynamic assessment of Au-La and Au-Er binary systems

    Energy Technology Data Exchange (ETDEWEB)

    Dong, H.Q., E-mail: hongqun.dong@aalto.fi [Department of Electronics, Aalto University School of Science and Technology, FIN-02601 Espoo (Finland); Tao, X.M. [Key Laboratory of New Processing Technology for Nonferrous Metals and Materials of Ministry of Education, Department of Physics, Guangxi University, Nanning 530004 (China); Liu, H.S. [Scientific Center of Phase Diagrams and Materials Design, Central South University, Changsha, Hunan 410083 (China); Laurila, T.; Paulastro-Kroeckel, M. [Department of Electronics, Aalto University School of Science and Technology, FIN-02601 Espoo (Finland)

    2011-03-31

    Research highlights: > It's the first time that Au-La and Au-Er binary systems were thermodynamically assessed since 1985. > Besides, in the present work, the ab initio approach has been employed to calculate the formation enthalpies of the IMCs involved in Au-Er and Au-La binary systems, and then, by combining with all of the available experimental information, these two-system were thermodynamically optimized via CALPHAD method. Therefore, a more reliable thermodynamic description has been obtained for these systems. - Abstract: Phase relationships in Au-La and Au-Er binary systems have been thermodynamically assessed by using the CALPHAD technique. The existing thermodynamic descriptions of the systems were improved by incorporating the ab initio calculated enthalpies of formation of the intermetallic compounds, except for the Au{sub 51}La{sub 14} and Au{sub 10}Er{sub 7} phases. All the binary intermetallic compounds were treated as stoichiometric phases, while the solution phases, including liquid, fcc, bcc, and dhcp, were treated as substitutional solution phases and the excess Gibbs energies were formulated with Redlich-Kister polynomial function. As a result, two self-consist thermodynamic data sets for describing the Au-La and Au-Er binary systems were obtained.

  20. ANALYSIS OF THE MOTION OF AN EXTRASOLAR PLANET IN A BINARY SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Plávalová, Eva [Astronomical Institute, Slovak Academy of Science, Bratislava (Slovakia); Solovaya, Nina A., E-mail: plavala@slovanet.sk, E-mail: solov@sai.msu.ru [Sternberg State Astronomical Institute, Lomonosov Moscow State University, Moscow (Russian Federation)

    2013-11-01

    More than 10% of extra-solar planets (EPs) orbit in a binary or multiple stellar system. We investigated the motion of planets revolving in binary systems in the case of the three-body problem. We carried out an analysis of the motion of an EP revolving in a binary system with the following conditions: (1) a planet in a binary system revolves around one of the components (parent star); (2) the distance between the star's components is greater than that between the parent star and the orbiting planet (ratio of the semi-major axes is a small parameter); and (3) the mass of the planet is smaller than the mass of the stars, but is not negligible. The Hamiltonian of the system without short periodic terms was used. We expanded the Hamiltonian in terms of the Legendre polynomial and truncated after the second-order term, depending on only one angular variable. In this case, the solution of the system was obtained and the qualitative analysis of the motion was produced. We have applied this theory to real EPs and compared to the numerical integration. Analyses of the possible regions of motion are presented. It is shown that stable and unstable motions of EPs are possible. We applied our calculations to two binary systems hosting an EP and calculated the possible values for their unknown orbital elements.

  1. Design and Realization of Three Uplink HD Video Conferencing System Based on MCU%MCU级联的省—市—县三级高清视频会议系统设计

    Institute of Scientific and Technical Information of China (English)

    张常亮; 马渝勇; 刘一谦; 谭红宾

    2012-01-01

    Combined with practical experience, in this paper, the design and realization of HD video conferencing system in Sichuan province are introduced. How the MCU cascade is used to construct HD video conferencing system is then illustrated. Besides, the key technologies of HD video conferencing system arc studied. Among these technologies, the HD signal interface and MCU cascade method are mainly expounded.%结合实际经验,介绍了四川气象高清视频会议系统的设计和实现过程.重点阐述了如何使用MCU级联构建省—市—县三级高清视频会议系统,并对高清视频会议系统关键技术进行了研究和分析,详细介绍了高清信号接口和MCU级联的具体方法.

  2. Binary Systems with a Black Hole Component as Sources of Gravitational Waves

    CERN Document Server

    Koçak, D

    2016-01-01

    Discovery of gravitational waves by LIGO team (Abbott et al. 2016) bring a new era for observation of black hole systems. These new observations will improve our knowledge on black holes and gravitational physics. In this study, we present angular momentum loss mechanism through gravitational radiation for selected X-ray binary systems. The angular momentum loss in X-ray binary systems with a black hole companion due to gravitational radiation and mass loss time-scales are estimated for each selected system. In addition, their gravitational wave amplitudes are also estimated and their detectability with gravitational wave detectors has been discussed.

  3. Pulsational frequencies of the eclipsing delta-Scuti star HD 172189

    CERN Document Server

    Costa, J E S; Peña, J; Creevey, O; Li, Z P; Chevreton, M; Belmonte, J A; Alvarez, M; Machado, L Fox; Parrao, L; Hernendez, F Perez; Fernández, A; Fremy, J R; Pau, S; Alonso, R

    2007-01-01

    The eclipsing delta-Scuti star HD 172189 is a probable member of the open cluster IC 4756 and a promising candidate target for the CoRoT mission. The detection of pulsation modes is the first step in the asteroseismological study of the star. Further, the calculation of the orbital parameters of the binary system allows us to make a dynamical determination of the mass of the star, which works as an important constraint to test and calibrate the asteroseismological models. From a detailed frequency analysis of 210 hours of photometric data of HD 172189 obtained from the STEPHI XIII campaign we have identified six pulsation frequencies with a confidence level of 99% and a seventh with a 65% confidence level in the range between 100-300 uHz. In addiction, three eclipses were observed during the campaign, allowing us to improve the determination of the orbital period of the system.

  4. Relationship between the density of supercritical CO2 +ethanol binary system and its critical properties

    Institute of Scientific and Technical Information of China (English)

    张敬畅; 张建军; 曹维良

    2003-01-01

    The dependent relation between temperature and pressure of supercritical CO2 + ethanol binary system under the pressure range from 5 to 10 MPa with the variety of densities and mole fractions of ethanol that range from 0 to 2% was investigated by the static visual method in a constant volume. The critical temperature and pressure were experimentally determined simultaneously. The PTρ figures at different ethanol contents were described based on the determined pressure and temperature data, from which pressure of supercritical CO2 + ethanol binary system was found to increase linearly with the increasing temperature. P-T lines show certain convergent feature in a specific concentration of ethanol and the convergent points shift to the region of higher temperature and pressure with the increasing ethanol compositions. Furthermore, the effect of density and ethanol concentration on the critical point of CO2 + ethanol binary system was discussed in details. Critical points increase linearly with the increasing mole fraction of ethanol in specific density and critical points change at different densities. The critical compressibility factors Zc of supercritical CO2 + ethanol binary systems at different compositions of ethanol were calculated and Zc-ρ figure was obtained accordingly. It was found from Zc-ρ figure that critical compressibility factors of supercritical CO2 unitary or binary systems decline linearly with the increasing density, by which the critical point can be predicted precisely.

  5. Evidence for the Direct Detection of the Thermal Spectrum of the Non-Transiting Hot Gas Giant HD 88133 b

    Science.gov (United States)

    Piskorz, Danielle; Crockett, Nathan R.; Lockwood, Alexandra; Benneke, Björn; Blake, Geoffrey A.; Barman, Travis S.; Bender, Chad F.; Bryan, Marta; Carr, John S.; Fischer, Debra; Howard, Andrew; Isaacson, Howard T.; Johnson, John A.

    2016-10-01

    We target the thermal emission spectrum of the non-transiting gas giant HD 88133 b with high-resolution near-infrared spectroscopy, by treating the planet and its host star as a spectroscopic binary. For sufficiently deep summed flux observations of the star and planet across multiple epochs, it is possible to resolve the signal of the hot gas giant's atmosphere compared to the brighter stellar spectrum, at a level consistent with the aggregate shot noise of the full data set. To do this, we first perform a principal component analysis to remove the contribution of the Earth's atmosphere to the observed spectra. Then, we use a cross-correlation analysis to tease out the spectra of the host star and HD 88133 b to determine its orbit and identify key sources of atmospheric opacity. In total, six epochs of Keck NIRSPEC L band observations and three epochs of Keck NIRSPEC K band observations of the HD 88133 system were obtained. Based on an analysis of the maximum likelihood curves calculated from the multi-epoch cross correlation of the full data set with two atmospheric models, we report the direct detection of the emission spectrum of the non-transiting exoplanet HD 88133 b and measure a radial projection of its Keplerian orbital velocity, its true mass, its orbital inclination, and dominant atmospheric species. This, combined with eleven years of radial velocity measurements of the system, provides the most up-to-date ephemeris for HD 88133.

  6. The formation and evolution of wind-capture discs in binary systems

    Science.gov (United States)

    Huarte-Espinosa, M.; Carroll-Nellenback, J.; Nordhaus, J.; Frank, A.; Blackman, E. G.

    2013-07-01

    We study the formation, evolution and physical properties of accretion discs formed via wind capture in binary systems. Using the adaptive mesh refinement (AMR) code AstroBEAR, we have carried out high-resolution 3D simulations that follow a stellar mass secondary in the corotating frame as it orbits a wind producing asymptotic giant branch (AGB) primary. We first derive a resolution criteria, based on considerations of Bondi-Hoyle flows, that must be met in order to properly resolve the formation of accretion discs around the secondary. We then compare simulations of binaries with three different orbital radii (Ro = 10, 15, 20 au). Discs are formed in all three cases, however, the size of the disc and, most importantly, its accretion rate decreases with orbital radii. In addition, the shape of the orbital motions of material within the disc becomes increasingly elliptical with increasing binary separation. The flow is mildly unsteady with `fluttering' around the bow shock observed. The discs are generally well aligned with the orbital plane after a few binary orbits. We do not observe the presence of any large-scale, violent instabilities (such as the flip-flop mode). For the first time, moreover, it is observed that the wind component that is accreted towards the secondary has a vortex tube-like structure, rather than a column-like one as it was previously thought. In the context of AGB binary systems that might be precursors to pre-planetary nebula (PPN) and planetary nebula (PN), we find that the wind accretion rates at the chosen orbital separations are generally too small to produce the most powerful outflows observed in these systems if the companions are main-sequence stars but marginally capable if the companions are white dwarfs. It is likely that many of the more powerful PPN and PN involve closer binaries than the ones considered here. The results also demonstrate principles of broad relevance to all wind-capture binary systems.

  7. Communication: radial distribution functions in a two-dimensional binary colloidal hard sphere system.

    Science.gov (United States)

    Thorneywork, Alice L; Roth, Roland; Aarts, Dirk G A L; Dullens, Roel P A

    2014-04-28

    Two-dimensional hard disks are a fundamentally important many-body model system in classical statistical mechanics. Despite their significance, a comprehensive experimental data set for two-dimensional single component and binary hard disks is lacking. Here, we present a direct comparison between the full set of radial distribution functions and the contact values of a two-dimensional binary colloidal hard sphere model system and those calculated using fundamental measure theory. We find excellent quantitative agreement between our experimental data and theoretical predictions for both single component and binary hard disk systems. Our results provide a unique and fully quantitative mapping between experiments and theory, which is crucial in establishing the fundamental link between structure and dynamics in simple liquids and glass forming systems.

  8. Rotationally-Driven Fragmentation for the Formation of the Binary Protostellar System L1551 IRS 5

    CERN Document Server

    Lim, Jeremy; Hanawa, Tomoyuki; Takakuwa, Shigehisa; Matsumoto, Tomoaki; Saigo, Kazuya

    2016-01-01

    Either bulk rotation or local turbulence is widely invoked to drive fragmentation in collapsing cores so as to produce multiple star systems. Even when the two mechanisms predict different manners in which the stellar spins and orbits are aligned, subsequent internal or external interactions can drive multiple systems towards or away from alignment thus masking their formation process. Here, we demonstrate that the geometrical and dynamical relationship between the binary system and its surrounding bulk envelope provide the crucial distinction between fragmentation models. We find that the circumstellar disks of the binary protostellar system L1551 IRS 5 are closely parallel not just with each other but also with their surrounding flattened envelope. Measurements of the relative proper motion of the binary components spanning nearly 30 yr indicate an orbital motion in the same sense as the envelope rotation. Eliminating orbital solutions whereby the circumstellar disks would be tidally truncated to sizes smal...

  9. Solid—Liquid Equilibria of Several Binary and Ternary Systems Containing Meleic Anhydride

    Institute of Scientific and Technical Information of China (English)

    MAPeisheng; CHENMingming; 等

    2002-01-01

    Solid-liquid equilibria(SLE) of three binary systems and seven ternary systems containing maleic anhydride(MA) are measured by visual method. The experimental data are compared with the calculated ones with modified universal quasichemical functional group activity coefficient(UNIFAC) method in which the interaction parameters between groups come from two sources,dortmund data bank (DDB), if there′s any,and correlations based on our former presented experimental SLE data of twenty binary systems.New groups of MA,ACCOO group,COO group,>C=O group and cy-CH2 group are defined and the SLE data of maleic anhydride in isopropyl acetate in literature are cited in order to assess the new interaction parameters,correlated with Wilson equation and the λh equation.The modified UNIFAC method with these new regressed interaction parameters is also used to predict other three binary systems containing maleic anhydride.

  10. Observational Investigations on Contact Binaries in Multiple-star Systems and Star Clusters

    Science.gov (United States)

    Liu, L.

    2013-01-01

    The W UMa-type contact binaries are strongly interacting systems whose components both fill their critical Roche lobes and share a convective common envelope. The models of contact binaries are bottlenecked due to too many uncertain parameters. In the 1960s and 1970s, the common convective envelope model was accepted after several fierce controversies. And then, the thermal relaxation oscillation (TRO) model, the discontinuity model, and the angular momentum loss (AML) model appeared. However, in the past forty years, there lacked remarkable advance. The coexistence of many unknown parameters blocks the theoretical development of contact binaries. A study on the contact binaries in multiple star systems and star clusters, which could provide lots of information for their formation and evolution, may be a potential growing point for understanding these objects. More and more evidence shows that many of contact binaries are located in multiple star systems and star clusters. In this thesis, we observed and analyzed contact binaries in the forementioned systems. The observational and theoretical studies for contact binary are also summarized briefly. The results obtained are as follows: (1) Three contact binaries V1128 Tau, GZ And, VW Boo which possess visual companions show periodic oscillations. The period ranges from 16.7 years to 46.5 years. These oscillations probably come from the orbital movement of a close third body. (2) Four contact binaries GSC 02393-00680, V396 Mon, FU Dra, SS Ari which do not have visual companions also present periodic oscillations. Whether they are real members of multiple star systems needs further investigations. These oscillations probably result from the orbital movement of a close M-type companion. (3) The periods of three contact binaries EQ Cep, ER Cep and V371 Cep in the old open cluster NGC 188 show a long-term increase. There is a cyclic period oscillation in ER Cep, with a period of 5.4 years. We find that the total mass of

  11. Morphological Evolution of Disc Galaxies in Binary Systems

    CERN Document Server

    Chan, R

    2013-01-01

    We present the results of several numerical simulations of disc binary galaxies. It was performed detailed numerical N-body simulations of the dynamical interaction of two disc galaxies. The disc galaxies are embedded in spherical halos of dark matter and present central bulges. The dynamical evolution of the binary galaxy is analyzed in order to study the morphological evolution of the stellar distribution of the discs. The satellite galaxy is held on fixed, coplanar or polar discs, of eccentric ($e=0.1$, $e=0.4$ or $e=0.7$) orbits. Both galaxies have the same mass and size similar to the Milk Way. We have shown that the merge of two disc galaxy, depending on the initial conditions, can result in a disc or a lenticular galaxy, instead of an elliptical one. Besides, we have demonstrated that the time of merging increases linearly with the initial apocentric distance of the galaxies and decreases with the orbit's eccentricity. We also have shown that the tidal forces and the fusion of the discs can excite tran...

  12. Chromospherically active stars. X - Spectroscopy and photometry of HD 212280

    Science.gov (United States)

    Fekel, Francis C.; Browning, Jared C.; Henry, Gregory W.; Morton, Mary D.; Hall, Douglas S.

    1993-01-01

    The system HD 212280 is a chromospherically active double lined spectroscopic binary with an orbital period of 45.284 days and an eccentricity of 0.50. The spectrum is composite with spectral types of G8 IV and F5-8 V for the components. An estimated inclination of 78 +/- 8 deg results in masses of 1.7 and 1.4 solar mass for the G subgiant and mid-F star, respectively. The distance to the system is estimated to be 112 pc. Photometric observations obtained between 1987 November and 1992 June reveal that HD 212280 is a newly identified variable star with a V amplitude of about 0.15 mag and a mean period of 29.46 days. Our V data were divided into 11 sets and in all but one case two spots were required to fit the data. Lifetimes of 650 days and a minimum of 1350 days have been determined for two of the four spots. The differential rotation coefficient of 0.05 is relatively small. The age of the system is about 1.9 X 10 exp 9 yrs. The G subgiant is rotating slower than pseudosynchronously while the F-type star is rotating faster.

  13. Study on Phase Equilibrium Properties for CO2+Cosolvent Binary Systems

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In this study, the constant volume, visual method is used to measure thc critical point of CO2toluene, CO2+cyclohexane, CO2+n-butyraldehyde, CO2+i-butyraldchyde, CO2+methanol and CO2+alcohol binary systems. The relationship between critical point and the concentration of the entrainer for different substances has been discussed, and the comparison of the phase behavior of single component system and that of binary systems have been carried out.

  14. Isobaric Vapor—Liquid Equilibrium for Methyldichlorosilane+Methylvinyldichlorosilane+Toluene and Constituent Binary Systems

    Institute of Scientific and Technical Information of China (English)

    邱祖民; 孙Wei; 余淑娴; 余祖兵

    2003-01-01

    Vapor-liquid euilibrium (VLE) for a ternary system of Methyldichlorosilane+methylvinyldichlorosilane+toluene and constituent binary systems were measured at 101.3kPa using a new type of magnetical pump-ebulliometer,The equilibrium conpositions of the vapor phase of binary systems were calculated indirectly from the total pressure-temperature-liquid composition(pTx).The experimental data were correlated with the Wilson and NRTL(non-random two liquid )equations.The parameters of the Wilson moldel were employed to predict the ternary VLE data .The calculated boiling points were in good agreement with the experimental ones.

  15. Millions of Multiples: Detecting and Characterizing Close-Separation Binary Systems in Synoptic Sky Surveys

    CERN Document Server

    Terziev, Emil; Arcavi, Iair; Baranec, Christoph; Bloom, Joshua S; Bui, Khanh; Burse, Mahesh P; Chorida, Pravin; Das, H K; Dekany, Richard G; Kraus, Adam L; Kulkarni, S R; Nugent, Peter; Ofek, Eran O; Punnadi, Sujit; Ramaprakash, A N; Riddle, Reed; Tendulkar, Shriharsh P

    2012-01-01

    The direct detection of binary systems in wide-field surveys is limited by the size of the stars' point-spread-functions (PSFs). A search for elongated objects can find closer companions, but is limited by the precision to which the PSF shape can be calibrated for individual stars. We have developed the BinaryFinder algorithm to search for close binaries by using precision measurements of PSF ellipticity across wide-field survey images. We show that the algorithm is capable of reliably detecting binary systems down to approximately 1/5 of the seeing limit, and can directly measure the systems' position angles, separations and contrast ratios. To verify the algorithm's performance we evaluated 100,000 objects in Palomar Transient Factory (PTF) wide-field-survey data for signs of binarity, and then used the Robo-AO robotic laser adaptive optics system to verify the parameters of 44 high-confidence targets. We show that BinaryFinder correctly predicts the presence of close companions with a <5% false-positive...

  16. Apsidal motions of 90 eccentric binary systems in the Small Magellanic Cloud

    CERN Document Server

    Hong, K; Kim, S -L; Koo, J -R; Lee, C -U

    2016-01-01

    We examined light curves of 1138 stars brighter than 18.0 mag in the $I$ band and less than a mean magnitude error of 0.1 mag in the $V$ band from the OGLE-III eclipsing binary catalogue, and found 90 new binary systems exhibiting apsidal motion. In this study, the samples of apsidal motion stars in the SMC were increased by a factor of about 3 than previously known. In order to determine the period of the apsidal motion for the binaries, we analysed in detail both the light curves and eclipse timings using the MACHO and OGLE photometric database. For the eclipse timing diagrams of the systems, new times of minimum light were derived from the full light curve combined at intervals of one year from the survey data. The new 90 binaries have apsidal motion periods in the range of 12$-$897 years. An additional short-term oscillation was detected in four systems (OGLE-SMC-ECL-1634, 1947, 3035, and 4946), which most likely arises from the existence of a third body orbiting each eclipsing binary. Since the systems p...

  17. Black holes in stellar-mass binary systems: expiating original spin?

    Science.gov (United States)

    King, Andrew; Nixon, Chris

    2016-10-01

    We investigate systematically whether accreting black hole systems are likely to reach global alignment of the black hole spin and its accretion disc with the binary plane. In low-mass X-ray binaries (LMXBs), there is only a modest tendency to reach such global alignment, and it is difficult to achieve fully: except for special initial conditions, we expect misalignment of the spin and orbital planes by ˜1 rad for most of the LMXB lifetime. The same is expected in high-mass X-ray binaries. A fairly close approach to global alignment is likely in most stellar-mass ultraluminous X-ray binary systems (ULXs) where the companion star fills its Roche lobe and transfers mass on a thermal or nuclear time-scale to a black hole of lower mass. These systems are unlikely to show orbital eclipses, as their emission cones are close to the hole's spin axis. This offers a potential observational test, as models for ULXs invoking intermediate-mass black holes do predict eclipses for ensembles of ≳ 10 systems. Recent observational work shows that eclipses are either absent or extremely rare in ULXs, supporting the picture that most ULXs are stellar-mass binaries with companion stars more massive than the accretor.

  18. On the Possibility of Habitable Moons in the System of HD 23079: Results from Orbital Stability Studies

    CERN Document Server

    Cuntz, M; Eberle, J; Shukayr, A

    2013-01-01

    The aim of our study is to investigate the possibility of habitable moons orbiting the giant planet HD 23079b, a Jupiter-mass planet, which follows a low-eccentricity orbit in the outer region of HD 23079's habitable zone. We show that HD 23079b is able to host habitable moons in prograde and retrograde orbits, as expected, noting that the outer stability limit for retrograde orbits is increased by nearly 90% compared to that of prograde orbits, a result consistent with previous generalized studies. For the targeted parameter space it was found that the outer stability limit for habitable moons varies between 0.05236 and 0.06955 AU (prograde orbits) and between 0.1023 and 0.1190 AU (retrograde orbits) depending on the orbital parameters of the Jupiter-type planet if a minimum mass is assumed. These intervals correspond to 0.306 and 0.345 (prograde orbits) and 0.583 and 0.611 (retrograde orbits) of the planet's Hill radius. Larger stability limits are obtained if an increased value for the planetary mass m_p i...

  19. Study of complex properties of binary system of ethanol-methanol at extreme concentrations

    CERN Document Server

    Nilavarasi, K; Madhurima, V

    2016-01-01

    At low concentrations of methanol in ethanol-methanol binary system, the molecular interactions are seen to be uniquely complex. It is observed that the ethanol aggregates are not strictly hydrogen-bonded complexes; dispersion forces also play a dominant role in the self- association of ethanol molecules. On the addition of small amount of methanol to ethanol, the dipolar association of ethanol is destroyed. The repulsive forces between the two moieties dominate the behavior of the binary system at lower concentration of methanol. At higher concentration of methanol (> 30%), the strength and extent (number) of formation of hydrogen bonds between ethanol and methanol increases. The geometry of molecular structure at high concentration favors the fitting of component molecules with each other. Intermolecular interactions in the ethanol-methanol binary system over the entire concentration range were investigated in detail using broadband dielectric spectroscopy, FTIR, surface tension and refractive index studies...

  20. Realization of a Binary-Outcome Projection Measurement of a Three-Level Superconducting Quantum System

    Science.gov (United States)

    Jerger, Markus; Macha, Pascal; Hamann, Andrés Rosario; Reshitnyk, Yarema; Juliusson, Kristinn; Fedorov, Arkady

    2016-07-01

    Binary-outcome measurements allow one to determine whether a multilevel quantum system is in a certain state while preserving quantum coherence between all orthogonal states. In this paper, we explore different regimes of the dispersive readout of a three-level superconducting quantum system coupled to a microwave cavity in order to implement binary-outcome measurements. By designing identical cavity-frequency shifts for the first and second excited states of the system, we realize strong projective binary-outcome measurements onto its ground state with a fidelity of 94.3%. Complemented with standard microwave control and low-noise parametric amplification, this scheme enables the quantum nondemolition detection of leakage errors and can be used to create sets of compatible measurements to reveal the contextual nature of superconducting circuits.

  1. Interfacial Interactions and Nanostructure Changes in DPPG/HD Monolayer at the Air/Water Interface

    Directory of Open Access Journals (Sweden)

    Huaze Zhu

    2015-01-01

    Full Text Available Lung surfactant (LS plays a crucial role in regulating surface tension during normal respiration cycles by decreasing the work associated with lung expansion and therefore decreases the metabolic energy consumed. Monolayer surfactant films composed of a mixture of phospholipids and spreading additives are of optional utility for applications in lung surfactant-based therapies. A simple, minimal model of such a lung surfactant system, composed of 1,2-dipalmitoyl-sn-glycero-3-[phosphor-rac-(1-gylcerol] (DPPG and hexadecanol (HD, was prepared, and the surface pressure-area (π-A isotherms and nanostructure characteristics of the binary mixture were investigated at the air/water interface using a combination of Langmuir-Blodgett (LB and atomic force microscopy (AFM techniques. Based on the regular solution theory, the miscibility and stability of the two components in the monolayer were analyzed in terms of compression modulus (Cs-1 , excess Gibbs free energy (ΔGexcπ , activity coefficients (γ, and interaction parameter (ξ. The results of this paper provide valuable insight into basic thermodynamics and nanostructure of mixed DPPG/HD monolayers; it is helpful to understand the thermodynamic behavior of HD as spreading additive in LS monolayer with a view toward characterizing potential improvements to LS performance brought about by addition of HD to lung phospholipids.

  2. Deep HST-WFPC2 photometry of NGC 288. I. Binary Systems and Blue Stragglers

    CERN Document Server

    Bellazzini, M; Messineo, M; Monaco, L L; Rood, R T

    2001-01-01

    We present the first results of a deep WFPC2 photometric survey of the loose galactic globular cluster NGC 288. The fraction of binary systems is estimated from the color distribution of objects near the Main Sequence (MS) with a method analogous to that introduced by Rubenstein & Bailyn(1997). We have unequivocally detected a significant population of binary systems which has a radial distribution that has been significantly influenced by mass segregation. In the inner region of the cluster (r 1 r_h), f_b must be less than 0.10, and the most likely value is 0.0, independently of the adopted F(q). The detected population of binaries is dominated by primordial systems. The specific frequency of Blue Straggler Stars (BSS) is exceptionally high, suggesting that the BSS production mechanism via binary evolution can be very efficient. A large population of BSS is possible even in low density environments if a sufficient reservoir of primordial binaries is available. The observed distribution of BSS in the Colo...

  3. Deep Hubble Space Telescope WFPC2 Photometry of NGC 288. I. Binary Systems and Blue Stragglers

    Science.gov (United States)

    Bellazzini, Michele; Fusi Pecci, Flavio; Messineo, Maria; Monaco, Lorenzo; Rood, Robert T.

    2002-03-01

    We present the first results of a deep WFPC2 photometric survey of the loose galactic globular cluster NGC 288. The fraction of binary systems is estimated from the color distribution of objects near the main sequence (MS) with a method analogous to that introduced by Rubenstein & Bailyn. We have unequivocally detected a significant population of binary systems with a radial distribution that has been significantly influenced by mass segregation. In the inner region of the cluster (r=1rh), fb must be less than 0.10, and the most likely value is 0.0, independently of the adopted F(q). The detected population of binaries is dominated by primordial systems. The specific frequency of blue stragglers (BSs) is exceptionally high, suggesting that the BS production mechanism via binary evolution can be very efficient. A large population of BSs is possible even in low-density environments if a sufficient reservoir of primordial binaries is available. The observed distribution of BSs in the color-magnitude diagram is not compatible with a rate of BS production that has been constant in time, if it is assumed that all the BSs are formed by the merging of two stars. Based on observations made with the NASA/ESA Hubble Space Telescope at the Space Telescope Science Institute (STScI), which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with proposal GO-6804.

  4. Solubilization and quantification of lycopene in aqueous media in the form of cyclodextrin binary systems.

    Science.gov (United States)

    Vertzoni, Maria; Kartezini, Theodora; Reppas, Christos; Archontaki, Helen; Valsami, Georgia

    2006-02-17

    An optimized kneading method for the preparation of lycopene-cyclodextrin binary systems was developed leading to solubilization of lycopene in water and 5% (w/v) dextrose solution. Lycopene quantification in the prepared binary systems was performed by a developed spectrometric method that followed a successful single-step extraction with dichloromethane. Storage stability characteristics of the binary systems were studied at 4 degrees C in solution and at -20 degrees C in the lyophilized products. Lycopene content was monitored at lambda(max)=482 nm, the limit of detection was 0.41 microg/ml and relative standard deviation was less than 3.1%. The results obtained with the spectrometric method were confirmed by a HPLC method. In the presence of cyclodextrins, lycopene concentration in water was 8.0+/-1.0, 27.1+/-3.2 and 16.0+/-2.2 microg/ml for beta-CD, HP-beta-CD and Me-beta-CD, respectively. In 5% (w/v) aqueous dextrose solutions the corresponding values were 16.0+/-1.8, 48.0+/-5.1 and 4.0+/-0.5 microg/ml, respectively. At 4 degrees C, storage stability of lycopene-cyclodextrin binary systems in water or 5% (w/v) aqueous dextrose solutions, was limited (t(1/2)=1-4 days). Addition of the antioxidant sodium metabisulfite increased the stability of lycopene-HP-beta-CD binary system in water. At -20 degrees C, the lyophilized lycopene-cyclodextrin binary systems were stable for at least 2 weeks.

  5. Liquid crystalline behaviour of mixtures of structurally dissimilar mesogens in binary systems

    Indian Academy of Sciences (India)

    Jayrang S Dave; Meera R Menon; Pratik R Patel

    2002-06-01

    We have studied four binary systems comprising four ester components, viz. 4-nitrophenyl-4'--alkoxybenzoates (where -alkoxy is nbutoxy, C4, -hexyloxy, C6, -octyloxy, C8 and -decyloxy, C10) and one azo component, 4--decyloxy phenylazo-4'-isoamyloxy benzene. A variety of mesomorphic properties are observed in these mixtures. The properties of these systems are discussed on the basis of phase diagrams.

  6. Recognition of binary x-ray systems utilizing the doppler effect

    Science.gov (United States)

    Novak, B. L.

    1980-01-01

    The possibility of recognizing the duality of a single class of X-ray systems utilizing the Doppler effect is studied. The procedure is based on the presence of a period which coincides with the orbital period at the intensity of the radiation in a fixed energy interval of the X-ray component of a binary system.

  7. The formation of the black hole in the X-ray binary system V404 Cyg

    NARCIS (Netherlands)

    J.C.A. Miller-Jones; P.G. Jonker; G. Nelemans; S. Portegies Zwart; V. Dhawan; W. Brisken; E. Gallo; M.P. Rupen

    2009-01-01

    Using new and archival radio data, we have measured the proper motion of the black hole X-ray binary V404 Cyg to be 9.2 +/- 0.3 mas yr(-1). Combined with the systemic radial velocity from the literature, we derive the full three-dimensional heliocentric space velocity of the system, which we use to

  8. ROTATIONAL VELOCITIES OF INDIVIDUAL COMPONENTS IN VERY LOW MASS BINARIES

    Energy Technology Data Exchange (ETDEWEB)

    Konopacky, Q. M.; Macintosh, B. A. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550 (United States); Ghez, A. M. [UCLA Division of Astronomy and Astrophysics, Los Angeles, CA 90095-1562 (United States); Fabrycky, D. C. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); White, R. J. [Department of Physics and Astronomy, Georgia State University, Atlanta, GA 30303 (United States); Barman, T. S. [Lowell Observatory, 1400 W. Mars Hill Rd., Flagstaff, AZ 86001 (United States); Rice, E. L. [American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024-5192 (United States); Hallinan, G. [Department of Astrophysics, California Institute of Technology, MC 249-17, Pasadena, CA 91125 (United States); Duchene, G., E-mail: macintosh1@llnl.gov, E-mail: konopacky@di.utoronto.ca, E-mail: ghez@astro.ucla.edu, E-mail: fabrycky@ucolick.org, E-mail: white@chara.gsu.edu, E-mail: barman@lowell.edu, E-mail: erice@amnh.org, E-mail: gh@astro.caltech.edu, E-mail: gduchene@berkeley.edu [Astronomy Department, University of California, Berkeley, Hearst Field Annex B-20, CA 94720-3411 (United States)

    2012-05-01

    We present rotational velocities for individual components of 11 very low mass (VLM) binaries with spectral types between M7 and L7.5. These results are based on observations taken with the near-infrared spectrograph, NIRSPEC, and the Keck II laser guide star adaptive optics system. We find that the observed sources tend to be rapid rotators (v sin i > 10 km s{sup -1}), consistent with previous seeing-limited measurements of VLM objects. The two sources with the largest v sin i, LP 349-25B and HD 130948C, are rotating at {approx}30% of their break-up speed, and are among the most rapidly rotating VLM objects known. Furthermore, five binary systems, all with orbital semimajor axes {approx}<3.5 AU, have component v sin i values that differ by greater than 3{sigma}. To bring the binary components with discrepant rotational velocities into agreement would require the rotational axes to be inclined with respect to each other, and that at least one component is inclined with respect to the orbital plane. Alternatively, each component could be rotating at a different rate, even though they have similar spectral types. Both differing rotational velocities and inclinations have implications for binary star formation and evolution. We also investigate possible dynamical evolution in the triple system HD 130948A-BC. The close binary brown dwarfs B and C have significantly different v sin i values. We demonstrate that components B and C could have been torqued into misalignment by the primary star, A, via orbital precession. Such a scenario can also be applied to another triple system in our sample, GJ 569A-Bab. Interactions such as these may play an important role in the dynamical evolution of VLM binaries. Finally, we note that two of the binaries with large differences in component v sin i, LP 349-25AB and 2MASS 0746+20AB, are also known radio sources.

  9. Rotational Velocities of Individual Components in Very Low Mass Binaries

    Science.gov (United States)

    Konopacky, Q. M.; Ghez, A. M.; Fabrycky, D. C.; Macintosh, B. A.; White, R. J.; Barman, T. S.; Rice, E. L.; Hallinan, G.; Duchêne, G.

    2012-05-01

    We present rotational velocities for individual components of 11 very low mass (VLM) binaries with spectral types between M7 and L7.5. These results are based on observations taken with the near-infrared spectrograph, NIRSPEC, and the Keck II laser guide star adaptive optics system. We find that the observed sources tend to be rapid rotators (v sin i > 10 km s-1), consistent with previous seeing-limited measurements of VLM objects. The two sources with the largest v sin i, LP 349-25B and HD 130948C, are rotating at ~30% of their break-up speed, and are among the most rapidly rotating VLM objects known. Furthermore, five binary systems, all with orbital semimajor axes lsim3.5 AU, have component v sin i values that differ by greater than 3σ. To bring the binary components with discrepant rotational velocities into agreement would require the rotational axes to be inclined with respect to each other, and that at least one component is inclined with respect to the orbital plane. Alternatively, each component could be rotating at a different rate, even though they have similar spectral types. Both differing rotational velocities and inclinations have implications for binary star formation and evolution. We also investigate possible dynamical evolution in the triple system HD 130948A-BC. The close binary brown dwarfs B and C have significantly different v sin i values. We demonstrate that components B and C could have been torqued into misalignment by the primary star, A, via orbital precession. Such a scenario can also be applied to another triple system in our sample, GJ 569A-Bab. Interactions such as these may play an important role in the dynamical evolution of VLM binaries. Finally, we note that two of the binaries with large differences in component v sin i, LP 349-25AB and 2MASS 0746+20AB, are also known radio sources.

  10. Study of HD 169392A observed by CoRoT and HARPS

    CERN Document Server

    Mathur, S; Catala, C; Benomar, O; Davies, G R; Garcia, R A; Salabert, D; Ballot, J; Mosser, B; Regulo, C; Chaplin, W J; Elsworth, Y; Handberg, R; Hekker, S; Mantegazza, L; Michel, E; Poretti, E; Rainer, M; Roxburgh, I W; Samadi, R; Steslicki, M; Uytterhoeven, K; Verner, G A; Auvergne, M; Baglin, A; Forteza, S Barcelo; Baudin, F; Cortes, T Roca

    2012-01-01

    The numerous results obtained with asteroseismology thanks to space missions such as CoRoT and Kepler are providing a new insight on stellar evolution. After five years of observations, CoRoT is going on providing high-quality data. We present here the analysis of the double star HD169392 complemented by ground-based spectroscopic observations. This work aims at characterizing the fundamental parameters of the two stars, their chemical composition, the acoustic-mode global parameters including their individual frequencies, and their dynamics. We have analysed HARPS observations of the two stars to retrieve their chemical compositions. Several methods have been used and compared to measure the global properties of acoustic modes and their individual frequencies from the photometric data of CoRoT. The new spectroscopic observations and archival astrometric values suggest that HD169392 is a wide binary system weakly bounded. We have obtained the spectroscopic parameters for both components, suggesting the origin...

  11. Binary systems solubilities of inorganic and organic compounds, v.1 pt.2

    CERN Document Server

    Stephen, H

    2013-01-01

    Solubilities of Inorganic and Organic Compounds, Volume 1: Binary Systems, Part 1 is part of an approximately 5,500-page manual containing a selection from the International Chemical Literature on the Solubilities of Elements, Inorganic Compounds, Metallo-organic and Organic Compounds in Binary, Ternary and Multi-component Systems. A careful survey of the literature in all languages by a panel of scientists specially appointed for the task by the U.S.S.R. Academy of Sciences, Moscow, has made the compilation of this work possible. The complete English edition in five separately bound volumes w

  12. A massive binary black-hole system in OJ287 and a test of general relativity

    OpenAIRE

    Valtonen, M. J.; Lehto, H. J.; Nilsson, K.; Heidt, J.; Takalo, L. O.; Sillanpää, A.; Villforth, C.; Kidger, M.; Poyner, G.; Pursimo, T.; Zola, S.; Wu, J. -H.; Zhou, X.; Sadakane, K.; Drozdz, M.

    2008-01-01

    Tests of Einstein's general theory of relativity have mostly been carried out in weak gravitational fields where the space-time curvature effects are first-order deviations from Newton's theory. Binary pulsars provide a means of probing the strong gravitational field around a neutron star, but strong-field effects may be best tested in systems containing black holes. Here we report such a test in a close binary system of two candidate black holes in the quasar OJ287. This quasar shows quasi-p...

  13. Numerical calculations of mass transfer flow in semi-detached binary systems. [of stars

    Science.gov (United States)

    Edwards, D. A.; Pringle, J. E.

    1987-01-01

    The details of the mass transfer flow near the inner Lagrangian point in a semidetached binary system are numerically calculated. A polytropic equation of state with n = 3/2 is used. The dependence of the mass transfer rate on the degree to which the star overfills its Roche lobe is calculated, and good agreement with previous analytic estimates is found. The variation of mass transfer rate which occurs if the binary system has a small eccentricity is calculated and is used to cast doubt on the model for superhumps in dwarf novae proposed by Papaloizou and Pringle (1979).

  14. Hydrodynamic moving-mesh simulations of the common envelope phase in binary stellar systems

    CERN Document Server

    Ohlmann, Sebastian T; Pakmor, Ruediger; Springel, Volker

    2015-01-01

    The common envelope (CE) phase is an important stage in binary stellar evolution. It is needed to explain many close binary stellar systems, such as cataclysmic variables, Type Ia supernova progenitors, or X-ray binaries. To form the resulting close binary, the initial orbit has to shrink, thereby transferring energy to the primary giant's envelope that is hence ejected. The details of this interaction, however, are still not understood. Here, we present new hydrodynamic simulations of the dynamical spiral-in forming a CE system. We apply the moving-mesh code AREPO to follow the interaction of a $1M_\\odot$ compact star with a $2M_\\odot$ red giant possessing a $0.4M_\\odot$ core. The nearly Lagrangian scheme combines advantages of smoothed particle hydrodynamics and traditional grid-based hydrodynamic codes and allows us to capture also small flow features at high spatial resolution. Our simulations reproduce the initial transfer of energy and angular momentum from the binary core to the envelope by spiral shoc...

  15. Reducing False Alarms in Searches for Gravitational Waves from Coalescing Binary Systems

    CERN Document Server

    Rodriguez, Andres

    2008-01-01

    LIGO observatories in Livingston, LA and Hanford, WA may detect gravitational waves emitted from coalescing binary systems composed of two compact objects. In order to detect compact binary coalescence (CBC) events, LIGO searches utilize matched filtering techniques. Matched filtering is the optimal detection strategy for stationary, Gaussian noise, however, LIGO noise is often non-stationary, non-Gaussian. Non-stationary noise result in an excess of false candidate events, commonly known as false alarms. This thesis develops the r^2 test to reduce the false alarm rate for LIGO CBC searches. Results of the search for primordial black hole binary systems (where each object has less than 1M_solar), in LIGO's Third Science Run (S3) is also presented. Results of the r^2 test are shown for several LIGO CBC searches, including the binary neutron star searches in the Third and Fourth Science Runs (S3/S4), the S3/S4 primordial black hole searches, and the binary black hole search in the first three months of the Fift...

  16. A more effective coordinate system for parameter estimation of precessing compact binaries from gravitational waves

    CERN Document Server

    Farr, Benjamin; Farr, Will M; O'Shaughnessy, Richard

    2014-01-01

    Ground-based gravitational wave detectors are sensitive to a narrow range of frequencies, effectively taking a snapshot of merging compact-object binary dynamics just before merger. We demonstrate that by adopting analysis parameters that naturally characterize this 'picture', the physical parameters of the system can be extracted more efficiently from the gravitational wave data, and interpreted more easily. We assess the performance of MCMC parameter estimation in this physically intuitive coordinate system, defined by (a) a frame anchored on the binary's spins and orbital angular momentum and (b) a time at which the detectors are most sensitive to the binary's gravitational wave emission. Using anticipated noise curves for the advanced-generation LIGO and Virgo gravitational wave detectors, we find that this careful choice of reference frame and reference time significantly improves parameter estimation efficiency for BNS, NS-BH, and BBH signals.

  17. KIC 10080943: An eccentric binary system containing two pressure and gravity mode hybrid pulsators

    CERN Document Server

    Schmid, V S; Aerts, C; Degroote, P; Bloemen, S; Murphy, S J; Van Reeth, T; Papics, P I; Bedding, T R; Keen, M A; Prsa, A; Menu, J; Debosscher, J; Hrudkova, M; De Smedt, K; Lombaert, R; Nemeth, P

    2015-01-01

    Gamma Doradus and delta Scuti pulsators cover the transition region between low mass and massive main-sequence stars, and are as such critical for testing stellar models. When they reside in binary systems, we can combine two independent methods to derive critical information, such as precise fundamental parameters to aid asteroseismic modelling. In the Kepler light curve of KIC10080943, clear signatures of gravity and pressure mode pulsations have been found. Ground-based spectroscopy revealed this target to be a double-lined binary system. We present the analysis of four years of Kepler photometry and high-resolution spectroscopy to derive observational constraints, which will serve to evaluate theoretical predictions of the stellar structure and evolution for intermediate-mass stars. We used the method of spectral disentangling to determine atmospheric parameters for both components and derive the orbital elements. With phoebe we modelled the ellipsoidal variation and reflection signal of the binary in the...

  18. The Be/X-ray binary system V 0332+53: A Short Review

    CERN Document Server

    Caballero-Garcia, M D; Arabaci, M Ozbey; Hudec, R

    2015-01-01

    Be/X-ray binary systems provide an excellent opportunity to study the physics around neutron stars through the study of the behaviour of matter around them. Intermediate and low-luminosity type outbursts are interesting because they provide relatively clean environments around neutron stars. In these conditions the physics of the magnetosphere around the neutron star can be better studied without being very disturbed by other phenomena regarding the transfer of matter between the two components of the Be/X-ray binary system. A recent study presents the optical longterm evolution of the Be/X-ray binary V 0332+53 plus the X-ray emission mainly during the intermediate-luminosity outburst on 2008. In this paper we comment on the context of these observations and on the properties that can be derived through the analysis of them.

  19. The Earth-Moon system as a typical binary in the Solar System

    CERN Document Server

    Ipatov, S I

    2016-01-01

    Solid embryos of the Earth and the Moon, as well as trans-Neptunian binaries, could form as a result of contraction of the rarefied condensation which was parental for a binary. The angular momentum of the condensation needed for formation of a satellite system could be mainly acquired at the collision of two rarefied condensations at which the parental condensation formed. The minimum value of the mass of the parental condensation for the Earth-Moon system could be about 0.02 of the Earth mass. Besides the main collision, which was followed by formation of the condensation that was a parent for the embryos of the Earth and the Moon, there could be another main collision of the parental condensation with another condensation. The second main collision (or a series of similar collisions) could change the tilt of the Earth. Depending on eccentricities of the planetesimals that collided with the embryos, the Moon could acquire 0.04-0.3 of its mass at the stage of accumulation of solid bodies while the mass of th...

  20. Improving enzymatic production of diglycerides by engineering binary ionic liquid medium system.

    Science.gov (United States)

    Guo, Zheng; Kahveci, Derya; Ozçelik, Beraat; Xu, Xuebing

    2009-10-01

    The tunable property of ionic liquids (ILs) offers tremendous opportunity to rethink the strategy of current efforts to resolve technical challenges that occurred in many production approaches. To establish an efficient glycerolysis approach for enzymatic production of diglycerides (DG), this work reported a novel concept to improve DG yield by applying a binary IL system that consisted of one IL with better DG production selectivity and another IL being able to achieve higher conversion of triglycerides (TG). The candidates for combination were determined by individually examining lipase-catalyzed glycerolysis in different ILs, as a result, promising ones are divided into two groups based on their reaction specificities. The effects of parametric variables were then preliminarily evaluated, following a further investigation of the reaction performance in different binary IL systems from cross-group combinations. The combination of TOMA.Tf(2)N/Ammoeng 102 was employed for optimization by Response Surface Methodology. Eighty to eighty-five percent (mol%) of oil conversion and up to 90% (mol%) of total DG yield (73%, wt%) were obtained, which are markedly higher than those previously reported. This work demonstrated the practical feasibility to couple the technical advantage (high TG conversion and high DG production selective in this work) of individual ILs into a binary system to over-perform the reaction. It is believed that binary IL system could be also applicable to other enzymatic reaction systems for establishment of more efficient reaction protocols.

  1. Modeling the Formation and Evolution of Wind-Capture Disks In Binary Systems

    Science.gov (United States)

    Huarte-Espinosa, M.; Carroll-Nellenback, J.; Nordhaus, J.; Frank, A.; Blackman, E.

    2014-04-01

    In this talk I will present results of recent models of the formation, evolution and physical properties of accretion disks formed via wind capture in binary systems. Using the AMR code AstroBEAR, we have carried out high resolution 3D simulations that follow a stellar mass secondary in the co-rotating frame as it orbits a wind producing AGB primary. A resolution criteria, based on considerations of Bondi-Hoyle flows, must be met in order to properly resolve the formation of accretion disks around the secondary. We then compare simulations of binaries with three different orbital radii (10, 15, 20 AU). Disks are formed in all three cases, however the size of the disk and, most importantly, its accretion rate decreases with orbital radii. In addition, the shape of the orbital motions of material within the disk becomes increasingly elliptical with increasing binary separation. The flow is mildly unsteady with "fluttering" around the bow shock observed. The disks are generally well aligned with the orbital plane after a few binary orbits. We do not observe the presence of any large scale, violent instabilities (such as the flip-flop mode). For the first time it is observed that the wind component that is accreted towards the secondary has a vortex tube-like structure. In the context of AGB binary systems that might be precursors to Pre-Planetary and Planetary Nebula, we find that the wind accretion rates at the chosen orbital separations are generally too small to produce the most powerful outflows observed in these systems if the companions are main sequence stars but marginally capable if the companions are white dwarfs. It is likely that many of the more powerful PPN and PN involve closer binaries than the ones considered here.

  2. Orbital parameters and variability of the emission spectrum for the massive binary system 103 Tau

    Science.gov (United States)

    Tarasov, A. E.

    2016-09-01

    Based on high-resolution spectra taken near the He I 6678 Å line for the massive binary system 103 Tau, we have detected a weak absorption component belonging to the binary's secondary component. We have measured the radial velocities of both components, improved the previously known orbital parameters, and determined the new ones. The binary has an orbital period P orb = 58.305d, an orbital eccentricity e = 0.277, a radial velocity semi-amplitude of the bright component K A = 44.8 km s-1, and a component mass ratio M A / M B = 1.77. The absence of photometric variability and the estimates of physical parameters for the primary component suggest that the binary most likely has a considerable inclination of the orbital plane to the observer, i ≈ 50°-60°. In this case, the secondary component is probably a normal dwarf of spectral type B5-B8. Based on the spectra taken near the H α line, we have studied the variability of the emission profile. It is shown to be formed in the Roche lobe of the secondary component, but no traces of active mass exchange in the binary have been detected.

  3. Near-Infrared Polarimetry of the GG Tauri A Binary System

    Science.gov (United States)

    Itoh, Yoichi; Oasa, Yumiko; Kudo, Tomoyuki; Kusakabe, Nobuhiko; Hashimoto, Jun; Abe, Lyu; Brandner, Wolfgang; Brandt, Timothy D.; Carson, Joseph C.; Egner, Sebastian; Feldt, Markus; Grady, Carol A.; Guyon, Olivier; Hayano, Yutaka; Hayashi, Masahiko; Hayashi, Saeko S.; Henning, Thomas; Hodapp, Klaus W.; Ishii, Miki; Iye, Masanori; Janson, Markus; Kandori, Ryo; Knapp, Gillian R.; Kuzuhara, Masayuki; Kwon, Jungmi; Matsuo, Taro; McElwain, Michael W.; Miyama, Shoken; Morino, Jun-Ichi; Moro-Martin, Amaya; Nishimura, Tetsuo; Pyo, Tae-Soo; Serabyn, Eugene; Suenaga, Takuya; Suto, Hiroshi

    2014-01-01

    A high angular resolution near-infrared image that shows the intensity of polarization for the GG Tau A binary system was obtained with the Subaru Telescope. The image shows a circumbinary disk scattering the light from the central binary. The azimuthal profile of the intensity of polarization for the circumbinary disk is roughly reproduced by a simple disk model with the Henyey-Greenstein phase function and the Rayleigh function, indicating there are small dust grains at the surface of the disk. Combined with a previous observation of the circumbinary disk, our image indicates that the gap structure in the circumbinary disk orbits counterclockwise, but material in the disk orbits clockwise. We propose that there is a shadow caused by material located between the central binary and the circumbinary disk. The separations and position angles of the stellar components of the binary in the past 20 yr are consistent with the binary orbit with a = 33.4 AU and e = 0.34.

  4. Direct detection of the tertiary component in the massive multiple HD 150136 with VLTI

    Science.gov (United States)

    Sanchez-Bermudez, J.; Schödel, R.; Alberdi, A.; Barbá, R. H.; Hummel, C. A.; Maíz Apellániz, J.; Pott, J.-U.

    2013-06-01

    Context. Massive stars are of fundamental importance for almost all aspects of astrophysics, but there still exist large gaps in our understanding of their properties and formation because they are rare and therefore distant. It has been found that most O-stars are multiples. It may well be that almost all massive stars are born as triples or higher multiples, but their large distances require milliarcsecond angular resolution for a direct detection of the companions. Aims: HD 150136 is the nearest system to Earth with >100 M⊙ and provides a unique opportunity to study an extremely massive system. Recently, evidence for the existence of a third component in HD 150136, in addition to the tight spectroscopic binary that forms the main component, was found in spectroscopic observations. Our aim was to image and obtain astrometric and photometric measurements of this component using long-baseline optical interferometry to further constrain the nature of this component. Methods: We observed HD 150136 with the near-infrared instrument AMBER attached to the ESO VLT Interferometer, which provides an angular resolution of 2 mas. The recovered closure phases are robust to systematic errors and provide unique information on the source asymmetry. Therefore, they are of crucial relevance for both image reconstruction and model fitting of the source structure. Results: The third component in HD 150136 is clearly detected in the high-quality data from AMBER. It is located at a projected angular distance of 7.3 mas, or about 13 AU at the line-of-sight distance of HD 150136, at a position angle of 209 degrees east of north, and has a flux ratio of 0.25 with respect to the inner binary. Our findings agree with previous results and have permitted us to improve the orbital solutions of the tertiary around the inner system. Conclusions: We resolved the third component of HD 150136 in J, H and K filters. The luminosity and color of the tertiary agrees with the predictions and shows

  5. Near-periodical spin period evolution in the binary system LMC X-4

    CERN Document Server

    Molkov, S; Falanga, M; Tsygankov, S; Bozzo, E

    2016-01-01

    In this paper we investigated the long-term evolution of the pulse-period in the high-mass X-ray binary LMC X-4 by taking advantage of more than 43~yrs of measurements in the X-ray domain. Our analysis revealed for the first time that the source is displaying near-periodical variations of its spin period on a time scale of roughly 6.8~yrs, making LMC X-4 one of the known binary systems showing remarkable long term spin torque reversals. We discuss different scenarios to interpret the origin of these torque reversals.

  6. The OGLE Collection of Variable Stars. Eclipsing Binaries in the Magellanic System

    Science.gov (United States)

    Pawlak, M.; Soszyński, I.; Udalski, A.; Szymański, M. K.; Wyrzykowski, Ł.; Ulaczyk, K.; Poleski, R.; Pietrukowicz, P.; Kozłowski, S.; Skowron, D. M.; Skowron, J.; Mróz, P.; Hamanowicz, A.

    2016-12-01

    We present the collection of eclipsing binaries in the Large and Small Magellanic Clouds, based on the OGLE survey. It contains 48 605 systems, 40 204 belonging to the LMC and 8401 to the SMC. Out of the total number of presented here binaries, 16 374 are the new discoveries. We present the time-series photometry obtained for the selected objects during the fourth phase of the OGLE project. The catalog has been created using a two step machine learning procedure based on the Random Forest algorithm.

  7. Deriving the orbital properties of pulsators in binary systems through their light arrival time delays

    CERN Document Server

    Murphy, Simon J

    2015-01-01

    We present the latest developments to the phase modulation method for finding binaries among pulsating stars. We demonstrate how the orbital elements of a pulsating binary star can be obtained analytically, that is, without converting time delays to radial velocities by numerical differentiation. Using the time delays directly offers greater precision, and allows the parameters of much smaller orbits to be derived. The method is applied to KIC9651065, KIC10990452, and KIC8264492, and a set of the orbital parameters is obtained for each system. Radial velocity curves for these stars are deduced from the orbital elements thus obtained.

  8. A Photometric Study of the W UMa-type Eclipsing Binary System GSC 0445-1993

    Institute of Scientific and Technical Information of China (English)

    Yuan-Gui Yang; Sheng-Bang Qian; M. D. Koppelman

    2005-01-01

    Several new light minimum times for the eclipsing binary GSC 0445-1993 have been determined from the observations by Koppelman et al. and the orbital period of this ,system was revised. A photometric analysis was carried out using the 2003 version of the Wilson-Devinney code. The results reveal that GSC 0445-1993 is a W-type eclipsing binary with a mass ratio of q = 0.323(±0.002) and an over-contact degree of f = 22.8%(±4.2%). A small temperature difference between the components of AT = 135 K and an orbital inclination of i = 65.7°(±0.3°) were obtained. The asymmetry of its light curve (i.e., the O'Connell effect) for this binary star is explained by the presence of a dark spot on the more massive component.

  9. Measuring the spin of black holes in binary systems using gravitational waves

    CERN Document Server

    Vitale, Salvatore; Veitch, John; Raymond, Vivien; Sturani, Riccardo

    2014-01-01

    Compact binary coalescences are the most promising sources of gravitational waves (GWs) for ground based detectors. Binary systems containing one or two spinning black holes are particularly interesting due to spin-orbit (and eventual spin-spin) interactions, and the opportunity of measuring spins directly through GW observations. In this letter we analyze simulated signals emitted by spinning binaries with several values of masses, spins, orientation, and signal-to-noise ratio. We find that spin magnitudes and tilt angles can be estimated to accuracy of a few percent for neutron star--black hole systems and $\\sim$ 5-30% for black hole binaries. In contrast, the difference in the azimuth angles of the spins, which may be used to check if spins are locked into resonant configurations, cannot be constrained. We observe that the best performances are obtained when the line of sight is perpendicular to the system's total angular momentum, and that a sudden change of behavior occurs when a system is observed from ...

  10. Experimental investigation and thermodynamic assessment of the Mn–In binary system

    Energy Technology Data Exchange (ETDEWEB)

    Wang, L.Y. [Guangxi Key Laboratory of Information Materials, Guilin University of Electronic Technology, Guilin 541004 (China); School of Materials Science and Engineering, Guilin University of Electronic Technology, Guilin 541004 (China); Wang, J., E-mail: wangjiang158@163.com [Guangxi Key Laboratory of Information Materials, Guilin University of Electronic Technology, Guilin 541004 (China); School of Materials Science and Engineering, Guilin University of Electronic Technology, Guilin 541004 (China); Zhu, C.F.; Cheng, G.; Tang, C.Y. [Guangxi Key Laboratory of Information Materials, Guilin University of Electronic Technology, Guilin 541004 (China); School of Materials Science and Engineering, Guilin University of Electronic Technology, Guilin 541004 (China); Rao, G.H., E-mail: rgh@guet.edu.cn [Guangxi Key Laboratory of Information Materials, Guilin University of Electronic Technology, Guilin 541004 (China); School of Materials Science and Engineering, Guilin University of Electronic Technology, Guilin 541004 (China); Zhou, H.Y. [Guangxi Key Laboratory of Information Materials, Guilin University of Electronic Technology, Guilin 541004 (China); School of Materials Science and Engineering, Guilin University of Electronic Technology, Guilin 541004 (China)

    2015-05-10

    Highlights: • Three invariant reactions and liquidus were determined by thermal analysis. • The Mn–In binary system was assessed using CALPHAD method. • A set of self-consistent thermodynamic parameters was obtained. • The calculation results agree well with phase equilibria and thermodynamic data. - Abstract: In the present work, sixteen Mn–In alloys were investigated experimentally by means of thermal analysis and X-ray diffraction techniques. The temperatures of the invariant reactions and liquidus in the Mn–In binary system were determined. Based on the experimental results obtained in the present work and the critical review of the available experimental data from the published literature, the Mn–In binary system was assessed thermodynamically using the CALPHAD method. The solution phases including liquid, α-Mn, β-Mn, γ-Mn, δ-Mn and tetragonal-A6(In), are modeled by the substitutional solution model and their excess Gibbs energies are expressed with the Redlich–Kister polynomial. The intermetallic compound, InMn{sub 3}, is treated as a stoichiometric compound. A set of self-consistent thermodynamic parameters obtained finally to describe the Gibbs energies of various phases in the Mn–In binary system can be used to reproduce well the phase equilibria and thermodynamic data.

  11. A simple estimate of gravitational wave memory in binary black hole systems

    CERN Document Server

    Garfinkle, David

    2016-01-01

    A simple estimate is given of gravitational wave memory for the inspiral and merger of a binary black hole system. Here the memory is proportional to the total energy radiated and has a simple angular dependence. This estimate might be helpful in finding better numerical relativity memory waveforms.

  12. A massive binary black-hole system in OJ287 and a test of general relativity

    CERN Document Server

    Valtonen, M J; Nilsson, K; Heidt, J; Takalo, L O; Sillanpää, A; Villforth, C; Kidger, M; Poyner, G; Pursimo, T; Zola, S; Wu, J H; Zhou, X; Sadakane, K; Drozdz, M; Koziel, D; Marchev, D; Ogloza, W; Porowski, C; Siwak, M; Stachowski, G; Winiarski, M; Hentunen, V P; Nissinen, M; Liakos, A; Dogru, S

    2008-01-01

    Tests of Einstein's general theory of relativity have mostly been carried out in weak gravitational fields where the space-time curvature effects are first-order deviations from Newton's theory. Binary pulsars provide a means of probing the strong gravitational field around a neutron star, but strong-field effects may be best tested in systems containing black holes. Here we report such a test in a close binary system of two candidate black holes in the quasar OJ287. This quasar shows quasi-periodic optical outbursts at 12 yr intervals, with two outburst peaks per interval. The latest outburst occurred in September 2007, within a day of the time predicted by the binary black-hole model and general relativity. The observations confirm the binary nature of the system and also provide evidence for the loss of orbital energy in agreement (within 10 per cent) with the emission of gravitational waves from the system. In the absence of gravitational wave emission the outburst would have happened twenty days later.

  13. High-pressure density measurements for the binary system ethanol plus heptane

    DEFF Research Database (Denmark)

    Watson, G.; Zeberg-Mikkelsen, Claus Kjær; Baylaucq, A.;

    2006-01-01

    The density of the asymmetrical binary system composed of ethanol and heptane has been measured (630 points) for nine different compositions including the pure compounds at five temperatures in the range (293.15 to 333.15) K and 14 isobars up to 65 MPa with a vibrating-tube densimeter, The experi...

  14. Density measurements under pressure for the binary system 1-propanol plus toluene

    DEFF Research Database (Denmark)

    Zeberg-Mikkelsen, Claus Kjær; Andersen, Simon Ivar

    2005-01-01

    The density of the binary system composed of 1-propanol and toluene has been measured under pressure using a vibrating-tube densimeter. The measurements have been performed for four different compositions as well as the pure compounds at four temperatures in the range of (303.15 to 333.15) K and ...

  15. Alkali metal and ammonium chlorides in water and heavy water (binary systems)

    CERN Document Server

    Cohen-Adad, R

    1991-01-01

    This volume surveys the data available in the literature for solid-fluid solubility equilibria plus selected solid-liquid-vapour equilibria, for binary systems containing alkali and ammonium chlorides in water or heavy water. Solubilities covered are lithium chloride, sodium chloride, potassium chloride, rubidium chloride, caesium chloride and ammonium chloride in water and heavy water.

  16. Black holes in stellar-mass binary systems: expiating original spin?

    CERN Document Server

    King, Andrew

    2016-01-01

    We investigate systematically whether accreting black hole systems are likely to reach global alignment of the black hole spin and its accretion disc with the binary plane. In low-mass X-ray binaries (LMXBs) there is only a modest tendency to reach such global alignment, and it is difficult to achieve fully: except for special initial conditions we expect misalignment of the spin and orbital planes by ~1 radian for most of the LMXB lifetime. The same is expected in high-mass X-ray binaries (HMXBs). A fairly close approach to global alignment is likely in most stellar-mass ultraluminous X-ray binary systems (ULXs) where the companion star fills its Roche lobe and transfers on a thermal timescale to a black hole of lower mass. These systems are unlikely to show orbital eclipses, as their emission cones are close to the hole's spin axis. This offers a potential observational test, as models for ULXs invoking intermediate-mass black holes do predict eclipses for ensembles of > ~10 systems. Recent observational wo...

  17. High-pressure viscosity measurements for the ethanol plus toluene binary system

    DEFF Research Database (Denmark)

    Zeberg-Mikkelsen, Claus Kjær; Baylaucq, A.; Watson, G.

    2005-01-01

    The viscosity of the ethanol + toluene binary system has been measured with a falling-body viscometer for seven compositions as well as for the pure ethanol in the temperature range from 293.15 to 353.15 K and up to 100 MPa with an experimental uncertainty of 2%. At 0.1 MPa the viscosity has been...

  18. Automated Generation of Phase Diagrams for Binary Systems with Azeotropic Behavior

    DEFF Research Database (Denmark)

    Cismondi, Martin; Michelsen, Michael Locht; Zabaloy, Marcelo S.

    2008-01-01

    In this work, we propose a computational strategy and methods for the automated calculation of complete loci of homogeneous azeotropy of binary mixtures and the related Pxy and Txy diagrams for models of the equation-of-state (EOS) type. The strategy consists of first finding the system's azeotro...

  19. HD Radio技术

    Institute of Scientific and Technical Information of China (English)

    李栋

    2007-01-01

    HD Radio技术于2002年被美国FCC批准为美国AM与FM波段的数字广播标准。它在不影响现有模拟广播的前提下.使用现有模拟广播的频谱提供高清晰度的数字声音广播与数据业务。HD Radio基于IBOC(带内同频道)技术,是由iBiquity Digital公司开发的。

  20. The impact of viscosity on the morphology of gaseous flows in semidetached binary systems

    CERN Document Server

    Bisikalo, D V; Kuznetsov, O A; Chechetkin, V M

    2000-01-01

    Results of 3D gas dynamical simulation of mass transfer in binaries are presented for systems with various values of viscosity. Analysis of obtained solutions shows that in the systems with low value of viscosity the flow structure is qualitatively similar to one for systems with high viscosity. Presented calculations confirm that there is no shock interaction between the stream from L1 and the forming accretion disk (`hot spot') at any value of viscosity.

  1. Phase equilibria calculation of LaI3-MI (M=Na, K, Cs) binary systems

    Institute of Scientific and Technical Information of China (English)

    WANG Yu; SHAO Guoquan; LI Shaobo; SUN Yimin; QIAO Zhiyu

    2009-01-01

    The Gibbs energies of liquid phases in the LaI3-MI (M=Na, K, Cs) systems were described by the modified quasi-chemical model. From the measured phase equilibrium data of these binary systems, a set of thermodynamic functions were optimized by using the CAL-PHAD technique. The enthalpy of mixing and the interaction parameter of the liquid phase were predicted from known data for the LaI3-MI systems.

  2. Three-dimensional simulations of phase separation in model binary alloy systems with elasticity

    Energy Technology Data Exchange (ETDEWEB)

    Orlikowski, D.; Roland, C. [North Carolina State Univ., Raleigh, NC (United States); Sagui, C. [McGill Univ., Montreal, Quebec (Canada). Dept. of Physics; Somoza, A.S. [Univ. de Murcia (Spain). Dept. de Fisica

    1998-12-31

    The authors report on large-scale three-dimensional simulations of phase separation in model binary alloy systems in the presence of elastic fields. The elastic field has several important effects on the morphology of the system: the ordered domains are subject to shape transformations, and spatial ordering. In contrast to two-dimensional system, no significant slowing down in the growth is observed. There is also no evidence of any reverse coarsening of the domains.

  3. Thermodynamic analysis of the change of solid solubility in a binary system processed by mechanical alloying

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar, C. [Instituto de Materiales y Procesos Termomecanicos, Facultad de Ciencias de la Ingenieria, Universidad Austral de Chile, Av. General Lagos 2086, Valdivia (Chile)], E-mail: ceaguilar@uach.cl; Martinez, V. [TEKMETALL, Metallurgical Solutions S.L., Po de Manuel Lardizabal No17, 20018 Donostia-Gipuzkoa (Spain); Navea, L.; Pavez, O.; Santander, M. [Departamento de Metalurgia, Facultad de Ingenieria, Universidad de Atacama, Av. Copayapu 485, Copiapo (Chile)

    2009-03-05

    Using a non-equilibrium process, it is possible to extend the solid solubility range in metallic systems. Therefore, the main objective of this work was to apply a thermodynamic model to predict the change in the solubility limit of systems with positive enthalpy mixing (Cu-Cr and Fe-Cu) processed by mechanical alloying. It was found that increasing the density of crystalline defects alters the solubility limit in these binary systems.

  4. Discriminating Formation Channels of Binary Black Hole Systems with Advanced LIGO

    Science.gov (United States)

    Zevin, Michael; Rodriguez, Carl; Pankow, Chris; Kalogera, Vicky; Rasio, Fred

    2017-01-01

    The field of gravitational-wave astronomy has been initiated by the recent observations of binary black hole mergers. These observations illuminate objects that are inaccessible with electromagnetic telescopes, and open inquiries as to how heavy binary black hole systems form and merge. Two possible formation channels proposed for such systems are isolated binary evolution in galactic fields and dynamical formation in star clusters. Currently, the coarse localization of these gravitational-wave events cannot indicate the environment in which the binary formed, and the mass distributions and merger rates from simulations of the aforementioned formation channels do not have an appreciable difference. However, the component spins of the black holes have the potential to unveil the formation history of the system. In this talk, I will discuss how to match measurements of the black hole component spin alignment with the projected spin distributions produced by population synthesis simulations. Using this framework we will link the estimated black hole spin to the formation channel of a merger, thus leading to a more detailed picture of their environments and origins.

  5. Glass transition in binary eutectic systems: best glass-forming composition.

    Science.gov (United States)

    Wang, Li-Min; Li, Zijing; Chen, Zeming; Zhao, Yue; Liu, Riping; Tian, Yongjun

    2010-09-23

    The glass transition and glass-forming ability in a binary eutectic system of methyl o-toluate (MOT) versus methyl p-toluate (MPT) are studied across the whole composition range. The phase diagram is constructed to explore the best glass-forming composition as the characteristic temperatures of the glass transition, crystallization, eutectic, and liquidus are determined. The best vitrification region is found to locate between the eutectic and the midpoint compositions of the eutectic line, indicating a remarkable deviation from the eutectic composition. The compilation of various simple binary eutectic systems covering inorganic, metallic, ionic, and molecular glass-forming liquids reproduces the rule. Kinetics and thermodynamics in binary systems are investigated to associate with the rule. The composition dependence of the structural relaxation time and the kinetic fragility are presented with dielectric measurements. It is found that whereas mixing of binary miscible liquids kinetically favors glass formation, thermodynamic contribution to the deviation of the best glass-forming composition from eutectics is implied.

  6. Towards a Fundamental Understanding of Short Period Eclipsing Binary Systems Using Kepler Data

    Science.gov (United States)

    Prsa, Andrej

    Kepler's ultra-high precision photometry is revolutionizing stellar astrophysics. We are seeing intrinsic phenomena on an unprecedented scale, and interpreting them is both a challenge and an exciting privilege. Eclipsing binary stars are of particular significance for stellar astrophysics because precise modeling leads to fundamental parameters of the orbiting components: masses, radii, temperatures and luminosities to better than 1-2%. On top of that, eclipsing binaries are ideal physical laboratories for studying other physical phenomena, such as asteroseismic properties, chromospheric activity, proximity effects, mass transfer in close binaries, etc. Because of the eclipses, the basic geometry is well constrained, but a follow-up spectroscopy is required to get the dynamical masses and the absolute scale of the system. A conjunction of Kepler photometry and ground- based spectroscopy is a treasure trove for eclipsing binary star astrophysics. This proposal focuses on a carefully selected set of 100 short period eclipsing binary stars. The fundamental goal of the project is to study the intrinsic astrophysical effects typical of short period binaries in great detail, utilizing Kepler photometry and follow-up spectroscopy to devise a robust and consistent set of modeling results. The complementing spectroscopy is being secured from 3 approved and fully funded programs: the NOAO 4-m echelle spectroscopy at Kitt Peak (30 nights; PI Prsa), the 10- m Hobby-Eberly Telescope high-resolution spectroscopy (PI Mahadevan), and the 2.5-m Sloan Digital Sky Survey III spectroscopy (PI Mahadevan). The targets are prioritized by the projected scientific yield. Short period detached binaries host low-mass (K- and M- type) components for which the mass-radius relationship is sparsely populated and still poorly understood, as the radii appear up to 20% larger than predicted by the population models. We demonstrate the spectroscopic detection viability in the secondary

  7. Non-thermal emission from high-energy binaries through interferometric radio observations

    CERN Document Server

    Marcote, B

    2016-01-01

    High-mass binary systems involve extreme environments that produce non-thermal emission from radio to gamma rays. Only three types of these systems are known to emit persistent gamma-ray emission: colliding-wind binaries, high-mass X-ray binaries and gamma-ray binaries. This thesis is focused on the radio emission of high-mass binary systems through interferometric observations, and we have explored several of these sources with low- and high-frequency radio observations, and very high-resolution VLBI ones. We have studied two gamma-ray binaries, LS 5039 and LS I +61 303, at low frequencies. We have obtained their light-curves and spectra, and we have determined the physical properties of their radio emitting regions. We have also studied the gamma-ray binary HESS J0632+057 through VLBI observations. A new colliding wind binary, HD 93129A, has been discovered through VLBI and optical observations. Finally, we have conducted radio observations of two sources that were candidates to be gamma-ray binaries.

  8. Design of a Content Addressable Memory-based Parallel Processor implementing (−1+j-based Binary Number System

    Directory of Open Access Journals (Sweden)

    Tariq Jamil

    2014-11-01

    Full Text Available Contrary to the traditional base 2 binary number system, used in today’s computers, in which a complex number is represented by two separate binary entities, one for the real part and one for the imaginary part, Complex Binary Number System (CBNS, a binary number system with base (−1+j, is used to represent a given complex number in single binary string format. In this paper, CBNS is reviewed and arithmetic algorithms for this number system are presented. The design of a CBNS-based parallel processor utilizing content-addressable memory for implementation of associative dataflow concept has been described and software-related issues have also been explained.

  9. Applicability of four parameter formalisms in interpreting thermodynamic properties of binary systems

    Indian Academy of Sciences (India)

    S Acharya; J P Hajra

    2011-04-01

    The four parameter functions are generally considered to be adequate for representation of the thermodynamic properties for the strongly interacting binary systems. The present study involves a critical comparison in terms of applicability of the three well known four-parameter formalisms for the representation of the thermodynamic properties of binary systems. The study indicates that the derived values of the infinite dilution parameters based on the formalisms compare favourably with the computed data available in the literature. The standard deviations in terms of the partial and integral excess functions of all the models lie well within the experimental scatter of the computed data and coincide exactly with each other. The formalisms are useful in representation of the thermodynamic properties of most of the binary systems except for the Mg–Bi and Mg–In systems. In such systems, it appears that the additional compositional terms may be necessary for the formalisms for adequate description of behaviour of the systems. Since the derived values of the thermodynamic properties of all the formalisms match favourably over the entire compositional range for the systems as studied in the present research, any one of them may be used for adequate representation of the properties of the systems.

  10. Measurement of VLE data for binary lipids systems

    DEFF Research Database (Denmark)

    Cunico, Larissa; Ceriani, Roberta; Sarup, Bent;

    (monocaprylin) + fatty acid (palmitic acid)] and system 2 [monoacylglycerol (monocaprylin) + fatty ester (methyl stearate)]. System 1 is relevant in the purification steps of the deodorizer distillates while system 2 is relevant in the purification steps of biodiesel and bioglycerin. A non-ideal behavior...

  11. Monitoring system for phreatic eruptions and thermal behavior on Poás volcano hyperacidic lake, with permanent IR and HD cameras

    Science.gov (United States)

    Ramirez, C. J.; Mora-Amador, R. A., Sr.; Alpizar Segura, Y.; González, G.

    2015-12-01

    Monitoring volcanoes have been on the past decades an expanding matter, one of the rising techniques that involve new technology is the digital video surveillance, and the automated software that come within, now is possible if you have the budget and some facilities on site, to set up a real-time network of high definition video cameras, some of them even with special features like infrared, thermal, ultraviolet, etc. That can make easier or harder the analysis of volcanic phenomena like lava eruptions, phreatic eruption, plume speed, lava flows, close/open vents, just to mention some of the many application of these cameras. We present the methodology of the installation at Poás volcano of a real-time system for processing and storing HD and thermal images and video, also the process to install and acquired the HD and IR cameras, towers, solar panels and radios to transmit the data on a volcano located at the tropics, plus what volcanic areas are our goal and why. On the other hand we show the hardware and software we consider necessary to carry on our project. Finally we show some early data examples of upwelling areas on the Poás volcano hyperacidic lake and the relation with lake phreatic eruptions, also some data of increasing temperature on an old dome wall and the suddenly wall explosions, and the use of IR video for measuring plume speed and contour for use on combination with DOAS or FTIR measurements.

  12. A SECOND GIANT PLANET IN 3:2 MEAN-MOTION RESONANCE IN THE HD 204313 SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, Paul; Endl, Michael; Cochran, William D.; MacQueen, Phillip J.; Brugamyer, Erik J.; Barnes, Stuart I.; Caldwell, Caroline [Department of Astronomy and McDonald Observatory, University of Texas at Austin, Austin, TX 78712 (United States); Horner, J.; Wittenmyer, Robert A. [Department of Astrophysics and Optics, School of Physics, University of New South Wales, Sydney, NSW 2052 (Australia); Simon, Attila E., E-mail: paul@astro.as.utexas.edu [Konkoly Observatory of the Hungarian Academy of Sciences, P.O. Box 67, H-1525 Budapest (Hungary)

    2012-07-20

    We present eight years of high-precision radial velocity (RV) data for HD 204313 from the 2.7 m Harlan J. Smith Telescope at McDonald Observatory. The star is known to have a giant planet (Msin i = 3.5 M{sub J} ) on a {approx}1900 day orbit, and a Neptune-mass planet at 0.2 AU. Using our own data in combination with the published CORALIE RVs of Segransan et al., we discover an outer Jovian (Msin i = 1.6 M{sub J} ) planet with P {approx} 2800 days. Our orbital fit suggests that the planets are in a 3:2 mean motion resonance, which would potentially affect their stability. We perform a detailed stability analysis and verify that the planets must be in resonance.

  13. Gravitational Microlensing Evidence for a Planet Orbiting a Binary Star System

    CERN Document Server

    Bennett, D P; Becker, A C; Butler, N; Dann, J H; Kaspi, S; Leibowitz, E M; Lipkin, Yu M; Maoz, D; Mendelson, H; Peterson, B A; Quinn, J; Shemmer, O; Thomson, S; Turner, S E

    1999-01-01

    The study of extra-solar planetary systems has emerged as a new discipline of observational astronomy in the past few years with the discovery of a number of extra-solar planets. The properties of most of these extra-solar planets were not anticipated by theoretical work on the formation of planetary systems. Here we report observations and light curve modeling of gravitational microlensing event MACHO-97-BLG-41, which indicates that the lens system consists of a planet orbiting a binary star system. According to this model, the mass ratio of the binary star system is 3.8:1 and the stars are most likely to be a late K dwarf and an M dwarf with a separation of about 1.8 AU. A planet of about 3 Jupiter masses orbits this system at a distance of about 7 AU. If our interpretation of this light curve is correct, it represents the first discovery of a planet orbiting a binary star system and the first detection of a Jovian planet via the gravitational microlensing technique. It suggests that giant planets may be co...

  14. The HARPS search southern extra-solar planets. VII. A very hot jupiter orbiti HD 212301

    DEFF Research Database (Denmark)

    Lo Curto, G.; Mayor, M.; Clausen, J.V.;

    2006-01-01

    Stars: individual : HD212301 - stars : planetary systems - techniques : radial velocities - techniques: spectroscopic - instrumentation : spectrographs......Stars: individual : HD212301 - stars : planetary systems - techniques : radial velocities - techniques: spectroscopic - instrumentation : spectrographs...

  15. Ray trajectories, binomial of a new type, and the binary system

    CERN Document Server

    Yurkin, Alexander V

    2013-01-01

    The paper describes a new algorithm of construction of the nonlinear arithmetic triangle on the basis of numerical simulation and the binary system. It demonstrates that the numbers that fill the nonlinear arithmetic triangle may be binomial coefficients of a new type. An analogy has been drawn with the binomial coefficients calculated with the use of the Pascal triangle. The paper provides a geometrical interpretation of binomials of different types in considering the branching systems of rays.

  16. A narrow, edge-on disk resolved around HD 106906 with SPHERE

    CERN Document Server

    Lagrange, A -M; Gratton, R; Maire, A -L; Milli, J; Olofsson, J; Vigan, A; Bailey, V; Mesa, D; Chauvin, G; Boccaletti, A; Galicher, R; Girard, J M; Bonnefoy, M; Samland, M; Menard, F; Henning, T; Kenworthy, M; Thalmann, C; Beust, H; Beuzit, J -L; Brandner, W; Buenzli, E; Cheetham, A; Janson, M; Coroller, H le; Lannier, J; Mouillet, D; Peretti, S; Perrot, C; Salter, G; Sissa, E; Wahhaj, Z; Abe, L; Desidera, S; Feldt, M; Madec, F; Perret, D; Petit, C; Rabou, P; Soenke, C; Weber, L

    2015-01-01

    HD~106906AB is so far the only young binary system around which a planet has been imaged and a debris disk evidenced thanks to a strong IR excess. As such, it represents a unique opportunity to study the dynamics of young planetary systems. We aim at further investigating the close (tens of au scales) environment of the HD~106906AB system. We used the extreme AO fed, high contrast imager SPHERE recently installed on the VLT to observe HD~106906. Both the IRDIS imager and the Integral Field Spectrometer were used. We discovered a very inclined, ring-like disk at a distance of 65~au from the star. The disk shows a strong brightness asymmetry with respect to its semi-major axis. It shows a smooth outer edge, compatible with ejection of small grains by the stellar radiation pressure. We show furthermore that the planet's projected position is significantly above the disk's PA. Given the determined disk inclination, it is not excluded though that the planet could still orbit within the disk plane if at a large sep...

  17. Solid state amorphisation in binary systems prepared by mechanical alloying

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, G., E-mail: gemagonz@ivic.v [Lab. Ciencia e Ing. de Materiales, Instituto Venezolano de Investigaciones Cientificas, IVIC, Caracas (Venezuela, Bolivarian Republic of); Sagarzazu, A. [Lab. Ciencia e Ing. de Materiales, Instituto Venezolano de Investigaciones Cientificas, IVIC, Caracas (Venezuela, Bolivarian Republic of); Bonyuet, D. [Instituto de Investigacion en Biomedicina y Ciencias Aplicadas, Universidad de Oriente, Cumana (Venezuela, Bolivarian Republic of); D' Angelo, L. [UNEXPO, Universidad Experimental Politecnica Luis Caballero Mejias, Dpto. Ing. Mecanica (Venezuela, Bolivarian Republic of); Villalba, R. [Lab. Ciencia e Ing. de Materiales, Instituto Venezolano de Investigaciones Cientificas, IVIC, Caracas (Venezuela, Bolivarian Republic of)

    2009-08-26

    In the present work a detailed study of amorphisation in different systems prepared by mechanical alloying under the same experimental conditions was carried out, milling up to 50 and 100 h in some cases. The systems studied were: AlTi, AlNi, AlFe, FeNi, FeCo, NiMo, NiW, NiCo, MoW, CoMo. These systems were chosen to study the effect of Al-transition metal, transition metal-transition metal and also systems with large and small negative heat of mixing, different and similar crystal structures, atomic sizes and diffusion coefficients. Calculations based on the Miedema model for alloy formation and amorphisation on all the alloys studied were performed. The experimental results from X-ray diffraction and transmission electron microscopy showed that the systems based on Fe (FeNi, FeCo and FeAl) did not amorphised, even after milling for 100 h, and formed a stable solid solution with a nanometric grain size of 7 nm. The systems NiMo, NiW, MoW and CoMo (systems with small negative heat of mixing), showed amorphisation after 50 h of milling. NiAl and TiAl form an intermediate amorphous phase after around 20 h of milling and with further milling they recrystallize into a fcc solid solution. Agreement between the theoretical calculations based on the Miedema model and the experimental results was found in most of the systems.

  18. Binary Laser Direct Writing System and Its Applications

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A new laser direct writing system is introduced and the potential application of the diffractive optical elements (DOE's) fabricated by applying laser direct writing system are presented. The fabrication techniques by applying the laser direct writing are developed. Experimental results have been obtained by applying laser direct writing machine with line width of 5μm and 10μm.

  19. Reconfiguration of distribution system using a binary programming model

    Directory of Open Access Journals (Sweden)

    Md Mashud Hyder

    2016-03-01

    Full Text Available Distribution system reconfiguration aims to choose a switching combination of branches of the system that optimize certain performance criteria of power supply while maintaining some specified constraints. The ability to automatically reconfigure the network quickly and reliably is a key requirement of self-healing networks which is an important part of the future Smart Grid system. We present a unified mathematical framework, which allows us to consider different objectives of distribution system reconfiguration problems in a flexible manner, and investigate its performance. The resulting optimization problem is in quadratic form which can be solved efficiently by using a quadratic mixed integer programming (QMIP solver. The proposed method has been applied for reconfiguring different standard test distribution systems.

  20. Investigation of the Orbital Properties of Intermediate-Mass Eclipsing Binary Star Systems

    Science.gov (United States)

    Obryan, Sierra; Ryle, W. T.; Williams, S.

    2013-06-01

    This research examines the orbital properties of intermediate-mass eclipsing binary stars. A binary eclipsing star system consists of two stars which orbit their common center of mass and pass in front of one another from our point of view. Many intermediate-mass eclipsing binary systems have been identified from the All Sky Automated Survey. However, this survey fails to produce well resolved data on each individual eclipse. This study overcomes this issue with dedicated observations from small aperture telescopes. By measuring the brightness of the system during an eclipse, light curves for each system can be generated. This information can then be combined with spectroscopic data to determine important physical parameters of the system. In particular, a new data analysis software package will be used to find revised mass and radius estimates for these stars. Refined physical parameters are vital due to these stars being used as astronomical distance indicators and comparison standards. This study currently focuses on star systems BD +11 3569, TYC 5933-142-1, and V448 Mon.

  1. Tidal Interaction among Red Giants Close Binary Systems in APOGEE Database

    Science.gov (United States)

    Sun, Meng; Arras, Phil; Majewski, Steven R.; Troup, Nicholas William; Weinberg, Nevin N.

    2017-01-01

    Motivated by the newly discovered close binary systems in the Apache Point Observatory Galactic Evolution Experiment (APOGEE-1), the tidal evolution of binaries containing a red giant branch (RGB) star with a stellar or substellar companion was investigated. The tide raised by the companion in the RGB star leads to exchange of angular momentum between the orbit and the stellar spin, causing the orbit to contract. The tidal dissipation rate is computed using turbulent viscosity acting on the equilibrium tidal flow, where careful attention is paid to the effects of reduced viscosity for close-in companions. Evolutionary models for the RGB stars, from the zero-age main sequence to the present, were acquired from the MESA code. "Standard" turbulent viscosity gives rise to such a large orbital decay that many observed systems have decay times much shorter than the RGB evolution time. Several theories for "reduced" turbulent viscosity are investigated, and reduce the number of systems with uncomfortably short decay times.

  2. Critical evaluation and thermodynamic optimization of the U-Pb and U-Sb binary systems

    Science.gov (United States)

    Wang, Jian; Jin, Liling; Chen, Chuchu; Rao, Weifeng; Wang, Cuiping; Liu, Xingjun

    2016-11-01

    A complete literature review, critical evaluation and thermodynamic optimization of the phase diagrams and thermodynamic properties of U-Pb and U-Sb binary systems are presented. The CALculation of PHAse Diagrams (CALPHAD) method was used for the thermodynamic optimization, the results of which can reproduce all available reliable experimental phase equilibria and thermodynamic data. The modified quasi-chemical model in the pair approximation (MQMPA) was used for modeling the liquid solution. The Gibbs energies of all terminal solid solutions and intermetallic compounds were described by the compound energy formalism (CEF) model. All reliable experimental data of the U-Pb and U-Sb systems have been reproduced. A self-consistent thermodynamic database has been constructed for these binary systems; this database can be used in liquid-metal fuel reactor (LMFR) research.

  3. Gravitational radiation by point particle eccentric binary systems in the linearised characteristic formulation of general relativity

    CERN Document Server

    M., C E Cedeño

    2016-01-01

    We study a binary system composed of point particles of unequal masses in eccentric orbits in the linear regime of the characteristic formulation of general relativity, generalising a previous study found in the literature in which a system of equal masses in circular orbits is considered. We also show that the boundary conditions on the time-like world tubes generated by the orbits of the particles can be extended beyond circular orbits. Concerning the power lost by the emission of gravitational waves, it is directly obtained from the Bondi's News function. It is worth stressing that our results are completely consistent, because we obtain the same result for the power derived by Peters and Mathews, in a different approach, in their seminal paper of 1963. In addition, the present study constitutes a powerful tool to construct extraction schemes in the characteristic formalism to obtain the gravitational radiation produced by binary systems during the inspiralling phase.

  4. Eclipsing time variations in close binary systems: Planetary hypothesis vs. Applegate mechanism

    CERN Document Server

    Völschow, M; Perdelwitz, V; Banerjee, R

    2015-01-01

    The observed eclipsing time variations in post-common-envelope binaries (PCEBs) can be interpreted as potential evidence for massive Jupiter-like planets, or as a result of magnetic activity, leading to quasi-periodic changes in the quadrupole moment of the secondary star. The latter is commonly referred to as the Applegate mechanism. Following Brinkworth et al. (2006), we employ here an improved version of Applegate's model including the angular momentum exchange between a finite shell and the core of the star. The framework is employed to derive the general conditions under which the Applegate mechanism can work, and is subsequently applied to a sample of 16 close binary systems with potential planets, including 11 PCEBs. Further, we present a detailed derivation and study of analytical models which allow for an straightforward extension to other systems. Using our full numerical framework, we show that the Applegate mechanism can clearly explain the observed eclipsing time variations in 4 of the systems, w...

  5. On the Possibility of Habitable Trojan Planets in Binary Star Systems.

    Science.gov (United States)

    Schwarz, Richard; Funk, Barbara; Bazsó, Ákos

    2015-12-01

    Approximately 60% of all stars in the solar neighbourhood (up to 80% in our Milky Way) are members of binary or multiple star systems. This fact led to the speculations that many more planets may exist in binary systems than are currently known. To estimate the habitability of exoplanetary systems, we have to define the so-called habitable zone (HZ). The HZ is defined as a region around a star where a planet would receive enough radiation to maintain liquid water on its surface and to be able to build a stable atmosphere. We search for new dynamical configurations-where planets may stay in stable orbits-to increase the probability to find a planet like the Earth.

  6. The Formation and Evolution of Wind-Capture Disks In Binary Systems

    CERN Document Server

    Huarte-Espinosa, Martin; Nordhaus, Jason; Frank, Adam; Blackman, Eric G

    2012-01-01

    We study the formation, evolution and physical properties of accretion disks formed via wind capture in binary systems. Using the AMR code AstroBEAR, we have carried out high resolution 3D simulations that follow a stellar mass secondary in the co-rotating frame as it orbits a wind producing AGB primary. We first derive a resolution criteria, based on considerations of Bondi-Hoyle flows, that must be met in order to properly resolve the formation of accretion disks around the secondary. We then compare simulations of binaries with three different orbital radii (10, 15, 20 AU). Disks are formed in all three cases, however the size of the disk and, most importantly, its accretion rate decreases with orbital radii. In addition, the shape of the orbital motions of material within the disk becomes increasingly elliptical with increasing binary separation. The flow is mildly unsteady with "fluttering" around the bow shock observed. The disks are generally well aligned with the orbital plane after a few binary orbit...

  7. First all-sky search for continuous gravitational waves from unknown sources in binary systems

    Science.gov (United States)

    Aasi, J.; Abbott, B. P.; Abbott, R.; Abbott, T.; Abernathy, M. R.; Accadia, T.; Acernese, F.; Ackley, K.; Adams, C.; Adams, T.; Addesso, P.; Adhikari, R. X.; Affeldt, C.; Agathos, M.; Aggarwal, N.; Aguiar, O. D.; Ain, A.; Ajith, P.; Alemic, A.; Allen, B.; Allocca, A.; Amariutei, D.; Andersen, M.; Anderson, R.; Anderson, S. B.; Anderson, W. G.; Arai, K.; Araya, M. C.; Arceneaux, C.; Areeda, J.; Aston, S. M.; Astone, P.; Aufmuth, P.; Aulbert, C.; Austin, L.; Aylott, B. E.; Babak, S.; Baker, P. T.; Ballardin, G.; Ballmer, S. W.; Barayoga, J. C.; Barbet, M.; Barish, B. C.; Barker, D.; Barone, F.; Barr, B.; Barsotti, L.; Barsuglia, M.; Barton, M. A.; Bartos, I.; Bassiri, R.; Basti, A.; Batch, J. C.; Bauchrowitz, J.; Bauer, Th. S.; Behnke, B.; Bejger, M.; Beker, M. G.; Belczynski, C.; Bell, A. S.; Bell, C.; Bergmann, G.; Bersanetti, D.; Bertolini, A.; Betzwieser, J.; Beyersdorf, P. T.; Bilenko, I. A.; Billingsley, G.; Birch, J.; Biscans, S.; Bitossi, M.; Bizouard, M. A.; Black, E.; Blackburn, J. K.; Blackburn, L.; Blair, D.; Bloemen, S.; Blom, M.; Bock, O.; Bodiya, T. P.; Boer, M.; Bogaert, G.; Bogan, C.; Bond, C.; Bondu, F.; Bonelli, L.; Bonnand, R.; Bork, R.; Born, M.; Boschi, V.; Bose, Sukanta; Bosi, L.; Bradaschia, C.; Brady, P. R.; Braginsky, V. B.; Branchesi, M.; Brau, J. E.; Briant, T.; Bridges, D. O.; Brillet, A.; Brinkmann, M.; Brisson, V.; Brooks, A. F.; Brown, D. A.; Brown, D. D.; Brückner, F.; Buchman, S.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Burman, R.; Buskulic, D.; Buy, C.; Cadonati, L.; Cagnoli, G.; Calderón Bustillo, J.; Calloni, E.; Camp, J. B.; Campsie, P.; Cannon, K. C.; Canuel, B.; Cao, J.; Capano, C. D.; Carbognani, F.; Carbone, L.; Caride, S.; Castiglia, A.; Caudill, S.; Cavaglià, M.; Cavalier, F.; Cavalieri, R.; Celerier, C.; Cella, G.; Cepeda, C.; Cesarini, E.; Chakraborty, R.; Chalermsongsak, T.; Chamberlin, S. J.; Chao, S.; Charlton, P.; Chassande-Mottin, E.; Chen, X.; Chen, Y.; Chincarini, A.; Chiummo, A.; Cho, H. S.; Chow, J.; Christensen, N.; Chu, Q.; Chua, S. S. Y.; Chung, S.; Ciani, G.; Clara, F.; Clark, J. A.; Cleva, F.; Coccia, E.; Cohadon, P.-F.; Colla, A.; Collette, C.; Colombini, M.; Cominsky, L.; Constancio, M.; Conte, A.; Cook, D.; Corbitt, T. R.; Cordier, M.; Cornish, N.; Corpuz, A.; Corsi, A.; Costa, C. A.; Coughlin, M. W.; Coughlin, S.; Coulon, J.-P.; Countryman, S.; Couvares, P.; Coward, D. M.; Cowart, M.; Coyne, D. C.; Coyne, R.; Craig, K.; Creighton, J. D. E.; Creighton, T. D.; Crowder, S. G.; Cumming, A.; Cunningham, L.; Cuoco, E.; Dahl, K.; Dal Canton, T.; Damjanic, M.; Danilishin, S. L.; D'Antonio, S.; Danzmann, K.; Dattilo, V.; Daveloza, H.; Davier, M.; Davies, G. S.; Daw, E. J.; Day, R.; Dayanga, T.; Debreczeni, G.; Degallaix, J.; Deléglise, S.; Del Pozzo, W.; Denker, T.; Dent, T.; Dereli, H.; Dergachev, V.; De Rosa, R.; DeRosa, R. T.; DeSalvo, R.; Dhurandhar, S.; Díaz, M.; Di Fiore, L.; Di Lieto, A.; Di Palma, I.; Di Virgilio, A.; Donath, A.; Donovan, F.; Dooley, K. L.; Doravari, S.; Dossa, S.; Douglas, R.; Downes, T. P.; Drago, M.; Drever, R. W. P.; Driggers, J. C.; Du, Z.; Dwyer, S.; Eberle, T.; Edo, T.; Edwards, M.; Effler, A.; Eggenstein, H.; Ehrens, P.; Eichholz, J.; Eikenberry, S. S.; Endrőczi, G.; Essick, R.; Etzel, T.; Evans, M.; Evans, T.; Factourovich, M.; Fafone, V.; Fairhurst, S.; Fang, Q.; Farinon, S.; Farr, B.; Farr, W. M.; Favata, M.; Fehrmann, H.; Fejer, M. M.; Feldbaum, D.; Feroz, F.; Ferrante, I.; Ferrini, F.; Fidecaro, F.; Finn, L. S.; Fiori, I.; Fisher, R. P.; Flaminio, R.; Fournier, J.-D.; Franco, S.; Frasca, S.; Frasconi, F.; Frede, M.; Frei, Z.; Freise, A.; Frey, R.; Fricke, T. T.; Fritschel, P.; Frolov, V. V.; Fulda, P.; Fyffe, M.; Gair, J.; Gammaitoni, L.; Gaonkar, S.; Garufi, F.; Gehrels, N.; Gemme, G.; Genin, E.; Gennai, A.; Ghosh, S.; Giaime, J. A.; Giardina, K. D.; Giazotto, A.; Gill, C.; Gleason, J.; Goetz, E.; Goetz, R.; Gondan, L.; González, G.; Gordon, N.; Gorodetsky, M. L.; Gossan, S.; Goßler, S.; Gouaty, R.; Gräf, C.; Graff, P. B.; Granata, M.; Grant, A.; Gras, S.; Gray, C.; Greenhalgh, R. J. S.; Gretarsson, A. M.; Groot, P.; Grote, H.; Grover, K.; Grunewald, S.; Guidi, G. M.; Guido, C.; Gushwa, K.; Gustafson, E. K.; Gustafson, R.; Hammer, D.; Hammond, G.; Hanke, M.; Hanks, J.; Hanna, C.; Hanson, J.; Harms, J.; Harry, G. M.; Harry, I. W.; Harstad, E. D.; Hart, M.; Hartman, M. T.; Haster, C.-J.; Haughian, K.; Heidmann, A.; Heintze, M.; Heitmann, H.; Hello, P.; Hemming, G.; Hendry, M.; Heng, I. S.; Heptonstall, A. W.; Heurs, M.; Hewitson, M.; Hild, S.; Hoak, D.; Hodge, K. A.; Holt, K.; Hooper, S.; Hopkins, P.; Hosken, D. J.; Hough, J.; Howell, E. J.; Hu, Y.; Huerta, E.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh, M.; Huynh-Dinh, T.; Ingram, D. R.; Inta, R.; Isogai, T.; Ivanov, A.; Iyer, B. R.; Izumi, K.; Jacobson, M.; James, E.; Jang, H.

    2014-09-01

    We present the first results of an all-sky search for continuous gravitational waves from unknown spinning neutron stars in binary systems using LIGO and Virgo data. Using a specially developed analysis program, the TwoSpect algorithm, the search was carried out on data from the sixth LIGO science run and the second and third Virgo science runs. The search covers a range of frequencies from 20 Hz to 520 Hz, a range of orbital periods from 2 to ˜2,254 h and a frequency- and period-dependent range of frequency modulation depths from 0.277 to 100 mHz. This corresponds to a range of projected semimajor axes of the orbit from ˜0.6×10-3 ls to ˜6,500 ls assuming the orbit of the binary is circular. While no plausible candidate gravitational wave events survive the pipeline, upper limits are set on the analyzed data. The most sensitive 95% confidence upper limit obtained on gravitational wave strain is 2.3×10-24 at 217 Hz, assuming the source waves are circularly polarized. Although this search has been optimized for circular binary orbits, the upper limits obtained remain valid for orbital eccentricities as large as 0.9. In addition, upper limits are placed on continuous gravitational wave emission from the low-mass x-ray binary Scorpius X-1 between 20 Hz and 57.25 Hz.

  8. Close encounters of the third-body kind. [intruding bodies in binary star systems

    Science.gov (United States)

    Davies, M. B.; Benz, W.; Hills, J. G.

    1994-01-01

    We simulated encounters involving binaries of two eccentricities: e = 0 (i.e., circular binaries) and e = 0.5. In both cases the binary contained a point mass of 1.4 solar masses (i.e., a neutron star) and a 0.8 solar masses main-sequence star modeled as a polytrope. The semimajor axes of both binaries were set to 60 solar radii (0.28 AU). We considered intruders of three masses: 1.4 solar masses (a neutron star), 0.8 solar masses (a main-sequence star or a higher mass white dwarf), and 0.64 solar masses (a more typical mass white dwarf). Our strategy was to perform a large number (40,000) of encounters using a three-body code, then to rerun a small number of cases with a three-dimensional smoothed particle hydrodynamics (SPH) code to determine the importance of hydrodynamical effects. Using the results of the three-body runs, we computed the exchange across sections, sigma(sub ex). From the results of the SPH runs, we computed the cross sections for clean exchange, denoted by sigma(sub cx); the formation of a triple system, denoted by sigma(sub trp); and the formation of a merged binary with an object formed from the merger of two of the stars left in orbit around the third star, denoted by sigma(sub mb). For encounters between either binary and a 1.4 solar masses neutron star, sigma(sub cx) approx. 0.7 sigma(sub ex) and sigma(sub mb) + sigma(sub trp) approx. 0.3 sigma(sub ex). For encounters between either binary and the 0.8 solar masses main-sequence star, sigma(sub cx) approx. 0.50 sigma(sub ex) and sigma(sub mb) + sigma(sub trp) approx. 1.0 sigma(sub ex). If the main sequence star is replaced by a main-sequence star of the same mass, we have sigma(sub cx) approx. 0.5 sigma(sub ex) and sigma(sub mb) + sigma(sub trp) approx. 1.6 sigma(sub ex). Although the exchange cross section is a sensitive function of intruder mass, we see that the cross section to produce merged binaries is roughly independent of intruder mass. The merged binaries produced have semi

  9. Smearing of mass accretion rate variation by viscous processes in accretion disks in compact binary systems

    Science.gov (United States)

    Ghosh, A.; Chakrabarti, Sandip K.

    2016-09-01

    Variation of mass supply rate from the companion can be smeared out by viscous processes inside an accretion disk. Hence, by the time the flow reaches the inner edge, the variation in X-rays need not reflect the true variation of the mass supply rate at the outer edge. However, if the viscosity fluctuates around a mean value, one would expect the viscous time scale t_{{visc}} also to spread around a mean value. In high mass X-ray binaries, which are thought to be primarily wind-fed, the size of the viscous Keplerian disk is smaller and thus such a spread could be lower as compared to the low mass X-ray binaries which are primarily fed by Roche lobe overflow. If there is an increasing or decreasing trend in viscosity, the interval between enhanced emission would be modified systematically. In the absence of a detailed knowledge about the variation of mass supply rates at the outer edge, we study ideal circumstances where modulation must take place exactly in orbital time scales, such as when there is an ellipticity in the orbit. We study a few compact binaries using long term All Sky monitor (ASM) data (1.5-12 keV) of Rossi X-ray Timing Explorer (RXTE) and all sky survey data (15-50 keV) of Swift satellites by different methods to look for such smearing effects and to infer what these results can tell us about the viscous processes inside the respective disks. We employ three different methods to seek imprints of periodicity on the X-ray variation and found that in all the cases, the location of the peak in the power density spectra is consistent with the orbital frequencies. Interestingly, in high mass X-ray binaries the peaks are sharp with high rms values, consistent with a small Keplerian disk in a wind fed system. However, in low mass X-ray binaries with larger Keplerian disk component, the peaks are spreaded out with much lower rms values. X-ray reflections, or superhump phenomena which may also cause such X-ray modulations would not be affected by the size of

  10. Multiwavelength Studies of gamma-ray Binaries

    Science.gov (United States)

    Aragona, Christina

    2011-01-01

    High mass X-ray binaries (HMXBs) consist of an O or B star orbited by either a neutron star or a black hole. Of the 114 known Galactic HMXBs, a handful of these objects, dubbed gamma-ray binaries, have been observed to produce MeV-TeV emission. The very high energy emission can be produced either by accretion from the stellar wind onto a black hole or a collision between the stellar wind and a relativistic pulsar wind. Both these scenarios make gamma-ray binaries valuable nearby systems for studying the physics of shocks and jets. Currently, the nature of the compact object and the high energy production mechanism is unknown or unconfirmed in over half of these systems. My goal for this dissertation is to constrain the parameters describing two of these systems: LS 5039 and HD 259440. LS 5039 exhibits gamma-ray emission modulated with its orbital period. The system consists of an ON6.5V((f)) star and an unidentified compact companion. Using optical spectra from the CTIO 1.5m telescope, we found LS 5039 to have an orbital period of 3.90608 d and an eccentricity of 0.337. Spectra of the Halpha line observed with SOAR indicate a mass loss rate of ˜ 1.9x10 -8 M yr-1. Observations taken with ATCA at 13 cm, 6 cm, and 3 cm indicate radio fluxes between 10--40 mJy. The measurements show variability with time, indicating a source other than thermal emission from the stellar wind. HD 259440 is a B0pe star that was proposed as the optical counterpart to the gamma-ray source HESS J0632+057. Using optical spectra from the KPNO CF, KPNO 2.1m, and OHP telescopes, we find a best fit stellar effective temperature of 27500--30000 K, a log surface gravity of 3.75--4.0, a mass of 13.2--19.0 Msolar, and a radius of 6.0--9.6 Rsolar. By fitting the spectral energy distribution, we find a distance between 1.1--1.7 kpc. We do not detect any significant radial velocity shifts in our data, ruling out orbital periods shorter than one month. If HD 259440 is a binary, it is likely a long

  11. Analysis of the motion of an extrasolar planet in a binary system

    CERN Document Server

    Plávalová, E

    2012-01-01

    We investigated the motion of planets revolving in binary systems in the frame of the particular case of the three body problem. We analysed of the motion an extrasolar plant (EP) revolving in a binary system by following conditions; a) a planet in a binary system revolves around one of the components (parent star), b) the distance between the stars components is greater than between the parent star and the orbiting planet (ratio of these two distances is a small parameter), c) the mass of the planet is smaller than the mass of the star, but is not negligible. The Hamiltonian of the system without short periodic terms was used. Expanded in the terms of the Legendre polynomial and truncated after the second order term depending on the one angular variable. In this case the solution of the system was obtained and the qualitative analysis of motion was done. We have applied this theory to real EPs. Analysis of the possible regions of motion are presented. It is shown that the case of the stable and unstable moti...

  12. The synchronous rotations of Eris/Dysnomia and Orcus/Vanth binary systems

    Science.gov (United States)

    Rabinowitz, David L.; Owainati, Yasi

    2014-11-01

    We have measured the rotation periods of the Eris/Dysnomia and Orcus/Vanth binary systems using long-term observations obtained with the SMARTS 1.3m telescope at Cerro Tololo, combined with incidental observations obtained by the La Silla - QUEST survey on the ESO 1.0-m Schmidt at La Silla, and using historical observations of Eris published by others. We find that both binary systems are synchronous, with the dominant periodicity in their light curves matching their mutual orbit periods (9.54 and 15.774 days, respectively). For Orcus/Vanth, the reflected light from both bodies contributes to the signal. The measured periodicity could be due to the rotation of Orcus or Vanth separately, but it is most likely the system is doubly synchronous. For Eris/Dysnomia, only Eris is bright enough to contribute significantly to the observations. The conclusion is therefore unambiguous that Eris is synchronously rotating with the orbit of Dysnomia. This is surprising given that Eris is 500 times brighter than Dysnomia, and likely to be 100 to 10000 times more massive (assuming an albedo > 5% for Dysnomia). If Dysnomia has migrated outward from Eris owing to long-term tidal interactions, the time for Eris to slow from an initially fast rotation (period < 1 day) to a synchronous one is longer than the age of the solar system. We discuss the constraints these observations place on the relative albedos, masses, and internal composition of the two binary systems.

  13. The Quasi-Roche lobe overflow state in the evolution of Close Binary Systems containing a radio pulsar

    CERN Document Server

    Benvenuto, O G; Horvath, J E

    2014-01-01

    We study the evolution of close binary systems formed by a normal (solar composition), intermediate mass donor star together with a neutron star. We consider models including irradiation feedback and evaporation. These non-standard ingredients deeply modify the mass transfer stages of these binaries. While models that neglect irradiation feedback undergo continuous, long standing mass transfer episodes, models including these effect suffer a number cycles of mass transfer and detachment. During mass transfer the systems should reveal themselves as low-mass X-ray binaries (LMXBs), whereas when detached they behave as a binary radio pulsars. We show that at these stages irradiated models are in a Roche lobe overflow (RLOF) state or in a quasi-RLOF state. Quasi-RLOF stars have a radius slightly smaller than its Roche lobe. Remarkably, these conditions are attained for orbital period and donor mass values in the range corresponding to a family of binary radio pulsars known as "redbacks". Thus, redback companions ...

  14. Interspecies stress in momentum equations for dense binary particulate systems.

    Science.gov (United States)

    Zhang, D Z; Ma, X; Rauenzahn, R M

    2006-07-28

    For two-species particulate systems, ensemble averaged continuity and momentum equations for each species are derived based on the Liouville equation of the system. The ensemble average used is species specific. It is found that the interaction between species results in not only the interspecies force but also a stress in the momentum equations. In the limit that particles of one of the species can be considered as a continuum, the existence of the interspecies stress enables us to reduce the derived equations to the familiar form for dispersed two-phase flows.

  15. Eccentricity evolution in hierarchical triple systems with eccentric outer binaries

    CERN Document Server

    Georgakarakos, Nikolaos

    2014-01-01

    We develop a technique for estimating the inner eccentricity in hierarchical triple systems, with the inner orbit being initially circular, while the outer one is eccentric. We consider coplanar systems with well separated components and comparable masses. The derivation of short period terms is based on an expansion of the rate of change of the Runge-Lenz vector. Then, the short period terms are combined with secular terms, obtained by means of canonical perturbation theory. The validity of the theoretical equations is tested by numerical integrations of the full equations of motion.

  16. Direct Detection of the Tertiary Component in the Massive Multiple HD 150 136 with VLTI

    CERN Document Server

    Sanchez-Bermudez, J; Alberdi, A; Barbá, R H; Hummel, C A; Apellaníz, J Maíz; Pott, J -U

    2013-01-01

    Massive stars are of fundamental importance for almost all aspects of astrophysics, but there still exist large gaps in our understanding of their properties and formation because they are rare and therefore distant. It has been found that most O-stars are multiples. HD 150 136 is the nearest system to Earth with >100 M_sol, and provides a unique opportunity to study an extremely massive system. Recently, evidence for the existence of a third component in HD 150 136, in addition to the tight spectroscopic binary that forms the main component, was found in spectroscopic observations. Our aim was to image and obtain astrometric and photometric measurements of this component using long baseline optical interferometry to further constrain the nature of this component. We observed HD150136 with the near-infrared instrument AMBER attached to the ESO VLT Interferometer. The recovered closure phases are robust to systematic errors and provide unique information on the source asymmetry. Therefore, they are of crucial ...

  17. HD 98800: An Opportunity to Measure True Masses for Low-Mass PMS Stars

    Science.gov (United States)

    Soderblom, David

    1999-07-01

    HD 98800 became interesting when IRAS found it to have a large infrared excess, indicating a substantial dust disk. But ``HD 98800'' is, in fact, a quadruple system consisting of four K and M stars, and its Hipparcos parallax has now shown that this is a pre-main sequence system. The four stars are in two visible objects, each of which is a spectroscopic binary with a period of about one year. In particular, the Ba-Bb pair is an SB2 with an estimated semi-major axis of about 20 milliarcsec. In TRANS mode, FGS1R can cleanly resolve the Ba-Bb pair and can determine the relative orbit and luminosities for the two components. POS mode observations lead to an absolute orbit and a more precise parallax than is currently available. In this program we propose to follow the HD 98800 Ba-Bb pair over the course of a full orbit during Cycle 8. The combination of FGS1R-TRANS and FGS1R-POS observations will provide gravitational masses for two low-mass PMS stars. In addition, the co nstraints of coevality and knowled ge of the astrophysical properties of the components {temperatures, luminosities, composition} make these observations a crucial test of our models of pre-main sequence evolution. These may be the first true masses determined for low-mass PMS objects, and so can provide a fundamental test of PMS evolutionary tracks.

  18. Circumbinary ring, circumstellar disks, and accretion in the binary system UY Aurigae

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Ya-Wen; Ho, Paul T. P. [Academia Sinica, Institute of Astronomy and Astrophysics, Taipei, Taiwan (China); Dutrey, Anne; Guilloteau, Stéphane; Di Folco, Emmanuel [Université de Bordeaux, Observatoire Aquitain des Sciences de l' Univers, CNRS, UMR 5804, Laboratoire d' Astrophysique de Bordeaux, 2 rue de l' Observatoire, BP 89, F-33271 Floirac Cedex (France); Piétu, Vincent; Gueth, Fréderic [IRAM, 300 rue de la piscine, F-38406 Saint Martin d' Hères Cedex (France); Beck, Tracy [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Boehler, Yann [Centro de Radioastronomìa y Astrofìsica, UNAM, Apartado Postal 3-72, 58089 Morelia, Michoacàn (Mexico); Bary, Jeff [Department of Physics and Astronomy, Colgate University, 13 Oak Drive, Hamilton, NY 13346 (United States); Simon, Michal, E-mail: ywtang@asiaa.sinica.edu.tw [Stony Brook University, Stony Brook, NY 11794-3800 (United States)

    2014-09-20

    Recent exo-planetary surveys reveal that planets can orbit and survive around binary stars. This suggests that some fraction of young binary systems which possess massive circumbinary (CB) disks may be in the midst of planet formation. However, there are very few CB disks detected. We revisit one of the known CB disks, the UY Aurigae system, and probe {sup 13}CO 2-1, C{sup 18}O 2-1, SO 5(6)-4(5) and {sup 12}CO 3-2 line emission and the thermal dust continuum. Our new results confirm the existence of the CB disk. In addition, the circumstellar (CS) disks are clearly resolved in dust continuum at 1.4 mm. The spectral indices between the wavelengths of 0.85 mm and 6 cm are found to be surprisingly low, being 1.6 for both CS disks. The deprojected separation of the binary is 1.''26 based on our 1.4 mm continuum data. This is 0.''07 (10 AU) larger than in earlier studies. Combining the fact of the variation of UY Aur B in R band, we propose that the CS disk of an undetected companion UY Aur Bb obscures UY Aur Ba. A very complex kinematical pattern inside the CB disk is observed due to a mixing of Keplerian rotation of the CB disk, the infall and outflow gas. The streaming gas accreting from the CB ring toward the CS disks and possible outflows are also identified and resolved. The SO emission is found to be at the bases of the streaming shocks. Our results suggest that the UY Aur system is undergoing an active accretion phase from the CB disk to the CS disks. The UY Aur B might also be a binary system, making the UY Aur a triple system.

  19. SEARCHING FOR BINARY Y DWARFS WITH THE GEMINI MULTI-CONJUGATE ADAPTIVE OPTICS SYSTEM (GeMS)

    Energy Technology Data Exchange (ETDEWEB)

    Opitz, Daniela; Tinney, C. G. [School of Physics, University of New South Wales, NSW 2052 (Australia); Faherty, Jacqueline K. [Department of Terrestrial Magnetism, Carnegie Institution of Washington, Washington, DC 20015 (United States); Sweet, Sarah [Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia); Gelino, Christopher R.; Kirkpatrick, J. Davy, E-mail: daniela.opitz@student.unsw.edu.au [Infrared Processing and Analysis Center, MS 100-22, California Institute of Technology, Pasadena, CA 91125 (United States)

    2016-03-01

    The NASA Wide-field Infrared Survey Explorer (WISE) has discovered almost all the known members of the new class of Y-type brown dwarfs. Most of these Y dwarfs have been identified as isolated objects in the field. It is known that binaries with L- and T-type brown dwarf primaries are less prevalent than either M-dwarf or solar-type primaries, they tend to have smaller separations and are more frequently detected in near-equal mass configurations. The binary statistics for Y-type brown dwarfs, however, are sparse, and so it is unclear if the same trends that hold for L- and T-type brown dwarfs also hold for Y-type ones. In addition, the detection of binary companions to very cool Y dwarfs may well be the best means available for discovering even colder objects. We present results for binary properties of a sample of five WISE Y dwarfs with the Gemini Multi-Conjugate Adaptive Optics System. We find no evidence for binary companions in these data, which suggests these systems are not equal-luminosity (or equal-mass) binaries with separations larger than ∼0.5–1.9 AU. For equal-mass binaries at an age of 5 Gyr, we find that the binary binding energies ruled out by our observations (i.e., 10{sup 42} erg) are consistent with those observed in previous studies of hotter ultra-cool dwarfs.

  20. Trajectory exploration within asynchronous binary asteroid systems using refined Lagrangian coherent structures

    Science.gov (United States)

    Shang, Haibin; Wu, Xiaoyu; Cui, Pingyuan

    2017-02-01

    Ground observations have found that asynchronous systems constitute most of the population of the near-Earth binary asteroids. This paper concerns the trajectory of a particle in the asynchronous system which is systematically described using periodic ellipsoidal and spherical body models. Due to the non-autonomous characteristics of the asynchronous system, Lagrangian coherent structures (LCS) are employed to identify the various dynamical behaviors. To enhance the accuracy of LCS, a robust LCS finding algorithm is developed incorporating hierarchical grid refinement, one-dimensional search and variational theory verification. In this way, the intricate dynamical transport boundaries are detected efficiently. These boundaries indicate that a total of 15 types of trajectories exist near asynchronous binary asteroids. According to their Kepler energy variations, these trajectories can be grouped into four basic categories, i.e., transitory, escape, impact and flyby trajectories. Furthermore, the influence of the ellipsoid's spin period on the dynamical behavior is discussed in the context of the change of dynamical regions. We found that the transitory and impact motions occur easily in the synchronous-like binary systems, in which the rotation period of the ellipsoid is nearly equal to that of the mutual orbit. Meanwhile, the results confirm a positive correlation between the spinning rate of the ellipsoid and the probability of the escape and flyby trajectories. The LCS also reveal a marked increase in trajectory diversity after a larger initial energy is selected.

  1. Error correcting codes for binary unitary channels on multipartite quantum systems

    CERN Document Server

    Choi, M D; Kribs, D W; Zyczkowski, K; Choi, Man-Duen; Holbrook, John A.; Kribs, David W.; Zyczkowski, Karol

    2006-01-01

    We conduct an analysis of ideal error correcting codes for randomized unitary channels determined by two unitary error operators -- what we call ``binary unitary channels'' -- on multipartite quantum systems. In a wide variety of cases we give a complete description of the code structure for such channels. Specifically, we find a practical geometric technique to determine the existence of codes of arbitrary dimension, and then derive an explicit construction of codes of a given dimension when they exist. For instance, given any binary unitary noise model on an n-qubit system, we design codes that support n-2 qubits. We accomplish this by verifying a conjecture for higher rank numerical ranges of normal operators in many cases.

  2. Determination and Prediction of Binary Solubility for Aromatic-Tetraethylene Glycol (with Water) Systems

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The binary solubilities of tetraethylene glycol (TTEG) with benzene, toluene or p-xylene, were measured by the turbidity point method. In TTEG the content of water ranged from 0 to 5% and the test temperature ranged from 20℃ to 120℃. Increasing the temperature resulted in greater solubility of the aromatics in TTEG, while increasing the content of water caused the aromatic solubility to decrease. The benzene solubillity in TTEG was the greatest followed by toluene and xylene at the same water content and temperature. The mutual solubility was predicted by correlating the paramaters of a new group for the UNIFAC model for the aromatics extraction system. The modified UNIFAC group contribution model was used to predict the binary solubility of TTEG and aromatics. The average deviation between the experimental result and prediction is 4.06%. Therefore, the UNIFAC model can be used to describe the solubility phenomena for TTEG-aromatics systems.

  3. Markov-Binary Visibility Graph: a new method for analyzing Complex Systems

    CERN Document Server

    Sadra, Yaser; Ahadpour, Sodief

    2011-01-01

    In this work, we introduce a new and simple transformation from time series to complex networks based on markov-binary visibility graph(MBVG). Due to the simple structure of this transformation in comparison with other transformations be obtained more precise results. Moreover, several topological aspects of the constructed graph, such as degree distribution, clustering coefficient, and mean visibility length have been thoroughly investigated. Numerical simulations confirm the reliability of markov-binary visibility graph for time series analysis. This algorithm have the capability of distinguishing between uncorrelated and correlated systems. Finaly, we illustrate this algorithm analyzing the human heartbeat dynamics. The results indicate that the human heartbeat (RR-interval) time series of normally, Congestive Heart Failure (CHF) and Atrial Fibrillation (AF) subjects are uncorrelated, chaotic and correlated stochastic systems, respectively.

  4. The parameters of binary black hole system in PKS 1510-089

    Institute of Scientific and Technical Information of China (English)

    Li Juan; Fan Jun-Hui; Yuan Yu-Hai

    2007-01-01

    Observations of PKS 1510-089 indicate the existence of a deep flux minimum with a timescale of ~35 min and an interval of about 336±14 d. A binary black hole system is proposed to be at the nucleus of this object. The secondary black hole orbits around the primary black hole.The minimum is caused by the periodic eclipse of the primary black hole by the secondary black hole.Based on the observations of PKS 1510-089,we estimate the parameters of the binary black hole system.The masses for the primary and secondary black holes are 1.37×109M⊙(M⊙ is the solar mass) and 1.37×107M⊙,and the major axis for this pair being about 0.1 parsec(pc).

  5. DSC study of phase transitions of cephalin pseudo-binary systems in excess water

    Institute of Scientific and Technical Information of China (English)

    王邦宁; 谈夫

    1999-01-01

    The gel-liquid crystal phase transitions of the pseudo-binary systems of cephalins DMPE and DHPE in excess water were studied by differential scanning calorimetry. The phase diagram of the pseudo-binary systems has been given. The experiments showed that the partial phase separation in gel phase might occur at least at the mole fractions of DHPE below 0.1. The analysis by the model of ideal solution showed that both the cephalins were non-ideally miscible both in the gel phases and in the liquid crystal phases. The analysis by the model of regular solution showed that all the non-ideality parameters in the gel phases were larger than those in the liquid crystal phases at the same temperature. All the non-ideality parameters were not constant, but rather dependent on temperature.

  6. Thermal Diffusion in binary Surfactant Systems and Microemulsions

    OpenAIRE

    Arlt, B.

    2012-01-01

    In dieser Arbeit haben wir das Thermodiffusionsverhalten von mizellaren Systemen und Mikroemulsionen untersucht. Beide Systeme werden als Modellsysteme genutzt um zwei Fragestellungen zu beantworten. Die erste Fragestellung bezieht sich auf den Einfluss der Mizellenbildung nahe der kritischen Mizellenkonzentration (cmc) auf das Thermodiffusionsverhalten. Dazu untersuchen wir das Thermodiffusionsverhalten des nichtionischen Tensides n-Octyl beta-D-Glucopyranoside (C8G1) in Wasser, welches e...

  7. Prediction of vapor-liquid equilibriafor hydrocarbon binary systems by regular solution model

    OpenAIRE

    下山, 裕介; 米澤, 節子; 小渕, 茂寿; 福地, 賢治; 荒井, 康彦; Shimoyama, Yusuke; Yonezawa, Setsuko; Kobuchi, Shigetoshi; Fukuchi, Kenii; Arai, Yasuhiko

    2007-01-01

    Vapor-liquid equilibria (VLE) of hydrocarbon binary systems : hexane + benzene (25 °C), toluene + octane (60°C) and cyclohexane + toluene (50°C) were predicted by using a regular solution model. In the present model, the mixing entropy term (Flory-Huggins equation) is included and an interaction parameter between unlike molecules is introduced. Solubility parameters and molar volumes at each temperature required in calculation are estimated by previously proposed methods. VLE of hexane + benz...

  8. Comments on gravitational radiation damping and energy loss in binary systems

    Energy Technology Data Exchange (ETDEWEB)

    Ehlers, J.; Rosenblum, A.; Goldberg, J.N.; Havas, P.

    1976-09-01

    It is argued that a formula for the energy loss due to gravitaional radiation of bound systems such as binaries has not yet been derived either exactly or by means of a consistent approximation method within general relativity, a view which contradicts some widely accepted claims in the literature. The main aproaches used to obtain such a formula are critically reviewed, and it is pointed out that the derivations presented so far either contain inconsistencies or are incomplete. (AIP)

  9. Measuring the spin of black holes in binary systems using gravitational waves.

    Science.gov (United States)

    Vitale, Salvatore; Lynch, Ryan; Veitch, John; Raymond, Vivien; Sturani, Riccardo

    2014-06-27

    Compact binary coalescences are the most promising sources of gravitational waves (GWs) for ground-based detectors. Binary systems containing one or two spinning black holes are particularly interesting due to spin-orbit (and eventual spin-spin) interactions and the opportunity of measuring spins directly through GW observations. In this Letter, we analyze simulated signals emitted by spinning binaries with several values of masses, spins, orientations, and signal-to-noise ratios, as detected by an advanced LIGO-Virgo network. We find that for moderate or high signal-to-noise ratio the spin magnitudes can be estimated with errors of a few percent (5%-30%) for neutron star-black hole (black hole-black hole) systems. Spins' tilt angle can be estimated with errors of 0.04 rad in the best cases, but typical values will be above 0.1 rad. Errors will be larger for signals barely above the threshold for detection. The difference in the azimuth angles of the spins, which may be used to check if spins are locked into resonant configurations, cannot be constrained. We observe that the best performances are obtained when the line of sight is perpendicular to the system's total angular momentum and that a sudden change of behavior occurs when a system is observed from angles such that the plane of the orbit can be seen both from above and below during the time the signal is in band. This study suggests that direct measurement of black hole spin by means of GWs can be as precise as what can be obtained from x-ray binaries.

  10. Structure and Spectrum of Binary Classic Systems Confined in a Parabolic Trap

    Institute of Scientific and Technical Information of China (English)

    YANG Wen; ZENG Zhi

    2009-01-01

    @@ The static and dynamic properties of the two-dimensional classic system of two-species interacting charged par-ticles in a parabolic trap are studied. The ground state energy and configuration for different kinds of binary systems are obtained by Monte Carlo simulation and Newton optimization. The spectrum and normal modes vectors can be gained by diagonalizing the dynamical matrix of the system. It is found that the total particle number, particle number and mass-to-charge ratio of each species are decisive factors for the system structure and spectrum. The three intrinsic normal modes of single species Coulomb clusters are inherent, concluded from our numerical simulations and analytical results.

  11. Precise Estimates of the Physical Parameters for the Exoplanet System HD-17156 Enabled by HST FGS Transit and Asteroseismic Observations

    CERN Document Server

    Nutzman, Philip; McCullough, Peter R; Charbonneau, David; Christensen-Dalsgaard, Jørgen; Kjeldsen, Hans; Nelan, Edmund P; Brown, Timothy M; Holman, Matthew J

    2010-01-01

    We present observations of three distinct transits of HD 17156b obtained with the Fine Guidance Sensors (FGS) on board the Hubble Space Telescope} (HST). We analyzed both the transit photometry and previously published radial velocities to find the planet-star radius ratio R_p/R_s = 0.07454 +/- 0.00035, inclination i=86.49 +0.24/-0.20 deg, and scaled semi-major axis a/R = 23.19 +0.32/-0.27. This last value translates directly to a mean stellar density determination of 0.522 +0.021/-0.018 g cm^-3. Analysis of asteroseismology observations by the companion paper of Gilliland et al. (2009) provides a consistent but significantly refined measurement of the stellar mean density. We compare stellar isochrones to this density estimate and find M_s = 1.275 +/- 0.018 M_sun and a stellar age of $3.37 +0.20/-0.47 Gyr. Using this estimate of M_s and incorporating the density constraint from asteroseismology, we model both the photometry and published radial velocities to estimate the planet radius R_p= 1.0870 +/- 0.0066 ...

  12. Thermodynamic assessment of the Pd–Y binary system

    Directory of Open Access Journals (Sweden)

    Kardellass S.

    2013-09-01

    Full Text Available The Pd–Y system was critically assessed using the CALPHAD technique. The solution phases (liquid, b.c.c., f.c.c. and h.c.p. were modeled using the Redlich–Kister equation. The intermetallic compounds Pd3Y and PdY, which have homogeneity ranges, were treated as the formula (Pd,Y0.75(Pd,Y0.25 and (Pd,Y0.5(Pd,Y0.5 by a two-sublattice model with a mutual substitution of Pd and Y on both sublattices. The optimization was carried out in two steps. In the first treatment, Pd3Y and PdY are assumed to be stoichiometric compounds; in the second treatment they are treated by a sublattice model. The parameters obtained from the first treatment were used as starting values for the second treatment. The calculated phase diagram and the thermodynamic properties of the system are in satisfactory agreement with the experimental data.

  13. Windtalking Computers: Frequency Normalization, Binary Coding Systems and Encryption

    CERN Document Server

    Zirkind, Givon

    2009-01-01

    The goal of this paper is to discuss the application of known techniques, knowledge and technology in a novel way, to encrypt computer and non-computer data. To-date most computers use base 2 and most encryption systems use ciphering and/or an encryption algorithm, to convert data into a secret message. The method of having the computer "speak another secret language" as used in human military secret communications has never been imitated. The author presents the theory and several possible implementations of a method for computers for secret communications analogous to human beings using a secret language or; speaking multiple languages. The kind of encryption scheme proposed significantly increases the complexity of and the effort needed for, decryption. As every methodology has its drawbacks, so too, the data of the proposed system has its drawbacks. It is not as compressed as base 2 would be. However, this is manageable and acceptable, if the goal is very strong encryption: At least two methods and their ...

  14. HD 285507b

    DEFF Research Database (Denmark)

    Quinn, Samuel N.; White, Russel J.; Latham, David W.;

    2014-01-01

    We report the discovery of the first hot Jupiter in the Hyades open cluster. HD 285507b orbits a V = 10.47 K4.5V dwarf (M * = 0.734 M ☉; R * = 0.656 R ☉) in a slightly eccentric () orbit with a period of days. The induced stellar radial velocity corresponds to a minimum companion mass of M Psin i...... confidence that the planet does not transit. HD 285507b joins a small but growing list of planets in open clusters, and its existence lends support to a planet formation scenario in which a high stellar space density does not inhibit giant planet formation and migration. We calculate the circularization...... timescale for HD 285507b to be larger than the age of the Hyades, which may indicate that this planet's non-zero eccentricity is the result of migration via interactions with a third body. We also demonstrate a significant difference between the eccentricity distributions of hot Jupiters that have had time...

  15. Observations of TeV binary systems with the H.E.S.S. telescope

    CERN Document Server

    Bordas, Pol; de Naurois, Mathieu; Ohm, Stefan; Wilhelmi, Emma de Oña; Sushch, Iurii; Volpe, Francesca; Zabalza, Víctor

    2013-01-01

    Recent observations of binary systems obtained with the H.E.S.S. telescopes are providing crucial information on the physics of relativistic outflows and the engines powering them. We report here on new H.E.S.S. results on HESS J0632+057, PSR B1259-63/LS 2883, Eta Carinae and the recently discovered source HESS J1018-589. Despite the high-quality data obtained in the last years through both ground and space-based gamma-ray detectors, many questions on the mechanisms that permit binary systems to emit at gamma-rays remain open. In particular, it is becoming apparent that emission at high and very-high energies is uncorrelated in some gamma-ray binary systems, with bright GeV flares not observed at TeV energies (e.g. PSR B1259-63), and sources periodically detected at VHEs which are lacking its HE counterpart (e.g. HESS J0632+057). Our results mainly confirm the predictions derived previously for the studied sources, but unexpected results are also found in a few cases, which are discussed in the context of con...

  16. High-energy signatures of binary systems of supermassive black holes

    CERN Document Server

    Romero, Gustavo E; Pérez, Daniela

    2016-01-01

    Context. Binary systems of supermassive black holes are expected to be strong sources of long gravitational waves prior to merging. These systems are good candidates to be observed with forthcoming space-borne detectors. Only a few of these systems, however, have been firmly identified to date. Aims. We aim at providing a criterion for the identification of some supermassive black hole binaries based on the characteristics of the high-energy emission of a putative relativistic jet launched from the most massive of the two black holes. Methods. We study supermassive black hole binaries where the less massive black hole has carved an annular gap in the circumbinary disk, but nevertheless there is a steady mass flow across its orbit. Such a perturbed disk is hotter and more luminous than a standard thin disk in some regions. Assuming that the jet contains relativistic electrons, we calculate its broadband spectral energy distribution focusing on the inverse Compton up-scattering of the disk photons. We also comp...

  17. Stability and Fourier-series periodic solution in the binary stellar systems

    CERN Document Server

    Mia, Rajib

    2016-01-01

    In this paper, we use the restricted three body problem in the binary stellar systems, taking photogravitational effects of both the stars. The aim of this study is to investigate the motion of the infinitesimal mass in the vicinity of the Lagrangian points. We have computed semi-analytical expressions for the locations of the collinear points with the help of the perturbation technique. The stability of the triangular points is studied in stellar binary systems Kepler-34, Kepler-35, Kepler-413 and Kepler-16. To investigate the stability of the triangular points, we have obtained the expressions for critical mass which depends on the radiation of both primaries. Fourier-series method is applied to obtain periodic orbits of the infinitesimal mass around triangular points in binary stellar systems. We have obtained Fourier expansions of the periodic orbits around triangular points upto third order terms. A comparison is made between periodic orbits obtained by Fourier-series method and with Runge-Kutta integrat...

  18. Colliding Winds in Low-Mass Binary Star Systems: wind interactions and implications for habitable planets

    CERN Document Server

    Johnstone, C P; Pilat-Lohinger, E; Bisikalo, D; Güdel, M; Eggl, S

    2015-01-01

    Context. In binary star systems, the winds from the two components impact each other, leading to strong shocks and regions of enhanced density and temperature. Potentially habitable circumbinary planets must continually be exposed to these interactions regions. Aims. We study, for the first time, the interactions between winds from low-mass stars in a binary system, to show the wind conditions seen by potentially habitable circumbinary planets. Methods. We use the advanced 3D numerical hydrodynamic code Nurgush to model the wind interactions of two identical winds from two solar mass stars with circular orbits and a binary separation of 0.5 AU. As input into this model, we use a 1D hydrodynamic simulation of the solar wind, run using the Versatile Advection Code. We derive the locations of stable and habitable orbits in this system to explore what wind conditions potentially habitable planets will be exposed to during their orbits. Results. Our wind interaction simulations result in the formation of two stron...

  19. A 3D dynamical model of the colliding winds in binary systems

    CERN Document Server

    Parkin, E R

    2008-01-01

    We present a 3D dynamical model of the orbital induced curvature of the wind-wind collision region in binary star systems. Momentum balance equations are used to determine the position and shape of the contact discontinuity between the stars, while further downstream the gas is assumed to behave ballistically. An archimedean spiral structure is formed by the motion of the stars, with clear resemblance to high resolution images of the so-called ``pinwheel nebulae''. A key advantage of this approach over grid or smoothed particle hydrodynamic models is its significantly reduced computational cost, while it also allows the study of the structure obtained in an eccentric orbit. The model is relevant to symbiotic systems and Gamma-ray binaries, as well as systems with O-type and Wolf-Rayet stars. As an example application, we simulate the X-ray emission from hypothetical O+O and WR+O star binaries, and describe a method of ray tracing through the 3D spiral structure to account for absorption by the circumstellar m...

  20. Accretion, Ablation and Propeller Evolution in Close Millisecond Pulsar Binary Systems

    CERN Document Server

    Kiel, P D

    2013-01-01

    A model for the formation and evolution of binary millisecond radio pulsars in systems with low mass companions (< 0.1 Msun) is investigated using a binary population synthesis technique. Taking into account the non conservative evolution of the system due to mass loss from an accretion disk as a result of propeller action and from the companion via ablation by the pulsar, the transition from the accretion powered to rotation powered phase is investigated. It is shown that the operation of the propeller and ablation mechanisms can be responsible for the formation and evolution of black widow millisecond pulsar systems from the low mass X-ray binary phase at an orbital period of ~0.1 day. For a range of population synthesis input parameters, the results reveal that a population of black widow millisecond pulsars characterized by orbital periods as long as ~0.4 days and companion masses as low as ~0.005 Msun can be produced. The orbital periods and minimum companion mass of this radio millisecond pulsar popu...

  1. Eclipse timing variations to detect possible Trojan planets in binary systems

    CERN Document Server

    Schwarz, R; Funk, B; Zechner, R

    2016-01-01

    This paper is devoted to study the circumstances favourable to detect Trojan planets in close binary-star-systems by the help of eclipse timing variations (ETVs). To determine the probability of the detection of such variations with ground based telescopes and space telescopes (like former missions CoRoT and Kepler and future space missions like Plato, Tess and Cheops), we investigated the dynamics of binary star systems with a planet in tadpole motion. We did numerical simulations by using the full three-body problem as dynamical model. The stability and the ETVs are investigated by computing stability/ETV maps for different masses of the secondary star and the Trojan planet. In addition we changed the eccentricity of the possible Trojan planet. By the help of the libration amplitude $\\sigma$ we could show whether or not all stable objects are moving in tadpole orbits. We can conclude that many amplitudes of ETVs are large enough to detect Earth-like Trojan planets in binary star systems. As an application, ...

  2. A Showcase of Unique Binary Systems Discovered by the Kepler Satellite

    Science.gov (United States)

    Kirk, Brian; Prsa, A.; Conroy, K.; Bloemen, S.; Shporer, A.; Barclay, T.; Hambleton, K.; Devor, J.; Kinemuchi, K.; Fulton, B.

    2012-05-01

    The importance of eclipsing binaries in modern astrophysics ranges from deriving fundamental stellar parameters across the Hertzsprung-Russell Diagram and calibrating the mass-radius-temperature relationships to determining the distances in the Galaxy and beyond. The unprecedented quality and uninterrupted sampling of Kepler data with sub-millimag precision are a leap forward in observational capabilities and enable us to perform modeling and analysis of these systems to an unparalleled precision. Currently the Kepler mission is providing a nearly seamless stream of photometric data of approximately 2500 eclipsing binary stars in its 105-square degree field of view. The Kepler Eclipsing Binary (EB) catalog is continuously being augmented as more data are collected and EBs are being detected at longer periods. The quarterly data segments for the entire mission are “stitched” together and detrended by fitting a variable order Legendre series to the light curve baseline. Each system is then classified into a morphology type by the method of Locally Linear Embedding. By fitting a polynomial chain to the data an analytic representation is obtained and passed through a trained artificial neural network to yield the remaining parameters. The catalog now contains more than six times the number of EB systems originally observed in the Kepler FOV. This high-precision instrument holds great promise for the discovery of many objects and we present here a showcase of unique objects from the Q0 through Q9 data release.

  3. AL Cassiopeiae: An F-type Contact Binary System with a Cool Stellar Companion

    Science.gov (United States)

    Qian, S.-B.; Zhou, X.; Zola, S.; Zhu, L.-Y.; Zhao, E.-G.; Liao, W.-P.; Leung, K.-C.

    2014-11-01

    According to the general catalog of variable stars, AL Cas was classified as an EW-type eclipsing binary with a spectral type of B and an orbital period of P = 0.5005555 days. The first photometric light curves of the close binary in the B, V, R, and I bands are presented. New low-resolution spectra indicate that its spectral type is about F7 rather than B-type. A photometric analysis with the Wilson-Devinney method suggests that it is a contact binary (f = 39.3%) with a mass ratio of 0.61. Using 17 newly determined eclipse times together with those collected from the literature, we found that the observed-calculated (O - C) curve of AL Cas shows a cyclic change with a period of 86.6 yr and an amplitude of 0.0181 days. The periodic variation was analyzed for the light-travel time effect via the presence of a third body. The mass of the third body was determined to be M 3sin i' = 0.29(± 0.05) M ⊙ when a total mass of 2.14 M ⊙ for AL Cas is adopted. It is expected that the cool companion star may have played an important role in the origin and evolution of the system by removing angular momentum from the central binary system during early dynamical interaction and/or late dynamical evolution. This causes the original detached system to have a low angular momentum and a short initial orbital period. Then it can evolve into the present contact configuration via a case A mass transfer.

  4. Constructing optimized binary masks for reservoir computing with delay systems

    Science.gov (United States)

    Appeltant, Lennert; van der Sande, Guy; Danckaert, Jan; Fischer, Ingo

    2014-01-01

    Reservoir computing is a novel bio-inspired computing method, capable of solving complex tasks in a computationally efficient way. It has recently been successfully implemented using delayed feedback systems, allowing to reduce the hardware complexity of brain-inspired computers drastically. In this approach, the pre-processing procedure relies on the definition of a temporal mask which serves as a scaled time-mutiplexing of the input. Originally, random masks had been chosen, motivated by the random connectivity in reservoirs. This random generation can sometimes fail. Moreover, for hardware implementations random generation is not ideal due to its complexity and the requirement for trial and error. We outline a procedure to reliably construct an optimal mask pattern in terms of multipurpose performance, derived from the concept of maximum length sequences. Not only does this ensure the creation of the shortest possible mask that leads to maximum variability in the reservoir states for the given reservoir, it also allows for an interpretation of the statistical significance of the provided training samples for the task at hand.

  5. The long-period eccentric orbit of the particle accelerator HD 167971 revealed by long baseline interferometry

    Science.gov (United States)

    De Becker, M.; Sana, H.; Absil, O.; Le Bouquin, J.-B.; Blomme, R.

    2012-07-01

    Using optical long baseline interferometry, we resolved for the first time the two wide components of HD 167971, a candidate hierarchical triple system known to efficiently accelerate particles. Our multi-epoch Very Large Telescope Interferometer observations provide direct evidence for a gravitational link between the O8 supergiant and the close eclipsing O + O binary. The separation varies from 8 to 15 mas over the 3-year baseline of our observations, suggesting that the components evolve on a wide and very eccentric orbit (most probably e > 0.5). These results provide evidence that the wide orbit revealed by our study is not coplanar with the orbit of the inner eclipsing binary. From our measurements of the near-infrared luminosity ratio, we constrain the spectral classification of the components in the close binary to be O6-O7, and confirm that these stars are likely main-sequence objects. Our results are discussed in the context of the bright non-thermal radio emission already reported for this system, and we provide arguments in favour of a maximum radio emission coincident with periastron passage. HD 167971 turns out to be an efficient O-type particle accelerator that constitutes a valuable target for future high angular resolution radio imaging using Very Long Baseline Interferometry facilities. Based on observations collected at the European Southern Observatory, Paranal, Chile, under the programme IDs 381.D-0095, 086.D-0586 and 087.D-0264.

  6. On the incidence of eclipsing Am binary systems in the SuperWASP survey

    CERN Document Server

    Smalley, B; Pintado, O I; Gillon, M; Holdsworth, D L; Anderson, D R; Barros, S C C; Cameron, A Collier; Delrez, L; Faedi, F; Haswell, C A; Hellier, C; Horne, K; Jehin, E; Maxted, P F L; Norton, A J; Pollacco, D; Skillen, I; Smith, A M S; West, R G; Wheatley, P J

    2014-01-01

    The results of a search for eclipsing Am star binaries using photometry from the SuperWASP survey are presented. The light curves of 1742 Am stars fainter than V = 8.0 were analysed for the presences of eclipses. A total of 70 stars were found to exhibit eclipses, with 66 having sufficient observations to enable orbital periods to be determined and 28 of which are newly identified eclipsing systems. Also presented are spectroscopic orbits for 5 of the systems. The number of systems and the period distribution is found to be consistent with that identified in previous radial velocity surveys of `classical' Am stars.

  7. Stellar Scattering and the Formation of Hot-Jupiters in Binary Systems

    CERN Document Server

    Martí, J G

    2014-01-01

    Hot Jupiters (HJs) are usually defined as giant Jovian-size planets with orbital periods $P \\le 10$ days. Although they lie close to the star, several have finite eccentricities and significant misalignment angle with respect to the stellar equator. Two mechanisms have been proposed to explain the excited and misaligned sub-population of HJs: Lidov-Kozai migration and planet-planet scattering. Although both are based on completely different dynamical phenomena, they appear to be equally effective in generating hot planets. Nevertheless, there has been no detailed analysis comparing the predictions of both mechanisms. In this paper we present numerical simulations of Lidov-Kozai trapping of single planets in compact binary systems. Both the planet and the binary are initially placed in coplanar orbits, although the inclination of the impactor is assumed random. After the passage of the third star, we follow the orbital and spin evolution of the planet using analytical models based on the octupole expansion of ...

  8. Eclipsing binary systems as tests of low-mass stellar evolution theory

    CERN Document Server

    Feiden, Gregory A

    2015-01-01

    Stellar fundamental properties (masses, radii, effective temperatures) can be extracted from observations of eclipsing binary systems with remarkable precision, often better than 2%. Such precise measurements afford us the opportunity to confront the validity of basic predictions of stellar evolution theory, such as the mass-radius relationship. A brief historical overview of confrontations between stellar models and data from eclipsing binaries is given, highlighting key results and physical insight that have led directly to our present understanding. The current paradigm that standard stellar evolution theory is insufficient to describe the most basic relation, that of a star's mass to its radius, along the main sequence is then described. Departures of theoretical expectations from empirical data, however, provide a rich opportunity to explore various physical solutions, improving our understanding of important stellar astrophysical processes.

  9. Gravitational waves from resolvable massive black hole binary systems and observations with Pulsar Timing Arrays

    CERN Document Server

    Sesana, A; Volonteri, M

    2008-01-01

    Massive black holes are key components of the assembly and evolution of cosmic structures and a number of surveys are currently on-going or planned to probe the demographics of these objects and to gain insight into the relevant physical processes. Pulsar Timing Arrays (PTAs) currently provide the only means to observe gravitational radiation from massive black hole binary systems with masses >10^7 solar masses. The whole cosmic population produces a stochastic background that could be detectable with upcoming Pulsar Timing Arrays. Sources sufficiently close and/or massive generate gravitational radiation that significantly exceeds the level of the background and could be individually resolved. We consider a wide range of massive black hole binary assembly scenarios, we investigate the distribution of the main physical parameters of the sources, such as masses and redshift, and explore the consequences for Pulsar Timing Arrays observations. Depending on the specific massive black hole population model, we est...

  10. Compact object detection in self-lensing binary systems with a main-sequence star

    CERN Document Server

    Rahvar, S; Dominik, M

    2010-01-01

    Detecting compact objects by means of their gravitational lensing effect on an observed companion in a binary system has already been suggested almost four decades ago. However, these predictions were made even before the first observations of gravitational lensing, whereas nowadays gravitational microlensing surveys towards the Galactic bulge yield almost 1000 events per year where one star magnifies the light of a more distant one. With a specific view on those experiments, we therefore carry out simulations to assess the prospects for detection of the transient periodic magnification of the companion star, which lasts typically only a few hours binaries involving a main-sequence star. We find that detectability is given by the achievability of dense monitoring with the required photometric accuracy. In sharp contrast to earlier expectations by other authors, we find that main-sequence stars are not substantially less favourable targets to observe this effect than white dwarfs. The requirement of an almost ...

  11. Equipotential Surfaces and Lagrangian points in Non-synchronous, Eccentric Binary and Planetary Systems

    CERN Document Server

    Sepinsky, J F; Kalogera, V

    2006-01-01

    We investigate the existence and properties of equipotential surfaces and Lagrangian points in non-synchronous, eccentric binary star and planetary systems under the assumption of quasi-static equilibrium. We adopt a binary potential that accounts for non-synchronous rotation and eccentric orbits, and calculate the positions of the Lagrangian points as functions of the mass ratio, the degree of asynchronism, the orbital eccentricity, and the position of the stars or planets in their relative orbit. We find that the geometry of the equipotential surfaces may facilitate non-conservative mass transfer in non-synchronous, eccentric binary star and planetary systems, especially if the component stars or planets are rotating super-synchronously at the periastron of their relative orbit. We also calculate the volume-equivalent radius of the Roche lobe as a function of the four parameters mentioned above. Contrary to common practice, we find that replacing the radius of a circular orbit in the fitting formula of Eggl...

  12. HD gas analysis with Gas Chromatography and Quadrupole Mass Spectrometer

    CERN Document Server

    Ohta, T; Didelez, J -P; Fujiwara, M; Fukuda, K; Kohri, H; Kunimatsu, T; Morisaki, C; Ono, S; Rouille, G; Tanaka, M; Ueda, K; Uraki, M; Utsuro, M; Wang, S Y; Yosoi, M

    2011-01-01

    A gas analyzer system has been developed to analyze Hydrogen-Deuteride (HD) gas for producing frozen-spin polarized HD targets, which are used for hadron photoproduction experiments at SPring-8. Small amounts of ortho-H$_{2}$ and para-D$_{2}$ gas mixtures ($\\sim$0.01%) in the purified HD gas are a key to realize a frozen-spin polarized target. In order to obtain reliable concentrations of these gas mixtures in the HD gas, we produced a new gas analyzer system combining two independent measurements with the gas chromatography and the QMS. The para-H$_{2}$, ortho-H$_{2}$, HD, and D$_{2}$ are separated using the retention time of the gas chromatography and the mass/charge. It is found that the new gas analyzer system can measure small concentrations of $\\sim$0.01% for the otho-H$_2$ and D$_2$ with good S/N ratios.

  13. Activity Calculation by Application of Sub-Regular Solution Model in Binary Oxide Systems

    Institute of Scientific and Technical Information of China (English)

    HOU Yan-qing; XIE Gang; TAO Dong-ping; LI Rong-xing; YU Xiao-hua

    2012-01-01

    To confirm sub-regular solution model valid for predicting the activity of component in binary oxide systems, seven systems in the whole concentration and twelve systems presenting saturation concentration have been studied. The total average relative errors of component 1 and 2 are 3.2 % and 4.1% respectively by application of the sub-regular solution model into the systems within the whole concentration. However, the total average relative errors are 16 % and 1088 % in the systems presenting saturation concentration. The results show that sub-regular solu- tion model is not good for predicting the systems presenting saturation concentration, especially for the systems con- taining acidic or neutral oxide. The reason may be that the influence of the two types of oxide on the configuration is greater in binary oxide systems. These oxides can be present in the form of complex anion partly, Si-O, Al-O, Ti-O and so on, for example (SiO4)4-. That is contrary to sub-regular solution model which is supposed that the oxide systems consist of cation and O2-. But compared with regular solution model and quasi-regular solution model, sub- regular solution model is closer to the characteristics of actual solution and the calculated results are superior.

  14. Binary system and jet precession and expansion in G35.20-0.74N

    Science.gov (United States)

    Beltrán, M. T.; Cesaroni, R.; Moscadelli, L.; Sánchez-Monge, Á.; Hirota, T.; Kumar, M. S. N.

    2016-09-01

    Context. Atacama Large Millimeter/submillimeter Array (ALMA) observations of the high-mass star-forming region G35.20-0.74N have revealed the presence of a Keplerian disk in core B rotating about a massive object of 18 M⊙, as computed from the velocity field. The luminosity of such a massive star would be comparable to (or higher than) the luminosity of the whole star-forming region. To solve this problem it has been proposed that core B could harbor a binary system. This could also explain the possible precession of the radio jet associated with this core, which has been suggested by its S-shaped morphology. Aims: We establish the origin of the free-free emission from core B and investigate the existence of a binary system at the center of this massive core and the possible precession of the radio jet. Methods: We carried out VLA continuum observations of G35.20-0.74N at 2 cm in the B configuration and at 1.3 cm and 7 mm in the A and B configurations. The bandwidth at 7 mm covers the CH3OH maser line at 44.069 GHz. Continuum images at 6 and 3.6 cm in the A configuration were obtained from the VLA archive. We also carried out VERA observations of the H2O maser line at 22.235 GHz. Results: The observations have revealed the presence of a binary system of UC/HC Hii regions at the geometrical center of the radio jet in G35.20-0.74N. This binary system, which is associated with a Keplerian rotating disk, consists of two B-type stars of 11 and 6 M⊙. The S-shaped morphology of the radio jet has been successfully explained as being due to precession produced by the binary system. The analysis of the precession of the radio jet has allowed us to better interpret the IR emission in the region, which would be not tracing a wide-angle cavity open by a single outflow with a position angle of ~55°, but two different flows: a precessing one in the NE-SW direction associated with the radio jet, and a second one in an almost E-W direction. Comparison of the radio jet images

  15. Distillation of hydrogen isotopes for polarized HD target

    CERN Document Server

    Ohta, T; Didelez, J -P; Fujiwara, M; Fukuda, K; Kohri, H; Kunimatsu, T; Morisaki, C; Ono, S; Rouill', G; Tanaka, M; Ueda, K; Uraki, M; Utsuro, M; Wang, S Y; Yosoi, M

    2011-01-01

    We have developed a cryogenic distillation system to purify Hydrogen-Deuteride (HD) gas for a polarized HD target in LEPS experiments at SPring-8. A small amount of ortho-H$_2$ ($\\sim$0.01%) in the HD gas plays an important role in efficiently polarizing the HD target. Since there are 1$\\sim$5% impurities of H$_2$ and D$_2$ in commercially available HD gases, it is inevitable that the HD gas is purified up to $\\sim$99.99%. The distillation system has a cryogenic pot (17$\\sim$21 K) containing many small stainless steel cells called Heli-pack. Commercial HD gas with an amount of 5.2 mol is fed into the pot. We carried out three distillation runs by changing temperatures (17.5 K and 20.5 K) and gas extraction speeds (1.3 ml/min and 5.2 ml/min). The extracted gas was analyzed by using a gas analyzer system combining a quadrupole mass spectrometer with a gas chromatograph. The HD gas of 1 mol with a purity better than 99.99% has been successfully obtained. The effective NTS (Number of Theoretical Stages), which is...

  16. In search of RR Lyrae type stars in eclipsing binary systems. OGLE052218.07-692827.4: an optical blend

    CERN Document Server

    Prsa, A; Devinney, E J; Engle, S G

    2008-01-01

    During the OGLE-2 operation, Soszynski et al. (2003) found 3 LMC candidates for an RR Lyr-type component in an eclipsing binary system. Two of those have orbital periods that are too short to be physically plausible and hence have to be optical blends. For the third, OGLE052218.07-692827.4, we developed a model of the binary that could host the observed RR Lyr star. After being granted HST/WFPC2 time, however, we were able to resolve 5 distinct sources within a 1.3" region that is typical of OGLE resolution, proving that OGLE052218.07-692827.4 is also an optical blend. Moreover, the putative eclipsing binary signature found in the OGLE data does not seem to correspond to a physically plausible system; the source is likely another background RR Lyr star. There are still no RR Lyr stars discovered so far in an eclipsing binary system.

  17. The complex circumstellar environment of HD 142527

    NARCIS (Netherlands)

    Verhoeff, A. P.; Min, M.; Pantin, E.; Waters, L.B.F.M.; Tielens, A. G. G. M.; Honda, M.; Fujiwara, H.; Bouwman, J.; Van Boekel, R.; Dougherty, S.M.; de Koter, A.; Dominik, C.; Mulders, G. D.

    2011-01-01

    Context. The recent findings of gas giant planets around young A-type stars suggest that disks surrounding Herbig Ae/Be stars will develop planetary systems. An interesting case is HD142527, for which previous observations revealed a complex circumstellar environment and an unusually high ratio of i

  18. The complex circumstellar environment of HD142527

    NARCIS (Netherlands)

    Verhoeff, A. P.; Min, M.; Pantin, E.; Waters, L. B. F. M.; Tielens, A. G. G. M.; Honda, M.; Fujiwara, H.; Bouwman, J.; van Boekel, R.; Dougherty, S. M.; de Koter, A.; Dominik, C.; Mulders, G. D.

    2011-01-01

    Context. The recent findings of gas giant planets around young A-type stars suggest that disks surrounding Herbig Ae/Be stars will develop planetary systems. An interesting case is HD142527, for which previous observations revealed a complex circumstellar environment and an unusually high ratio of i

  19. MERLIN radio detection of an interaction zone within a binary Orion proplyd system

    CERN Document Server

    Graham, M F; Garrington, S T; O'Brien, T J; Henney, W J; O'Dell, C R

    2002-01-01

    Presented here are high angular resolution MERLIN 5 GHz (6 cm) continuum observations of the binary proplyd system, LV 1 in the Orion nebula, which consists of proplyd 168--326SE and its binary proplyd companion 168--326NW (separation 0.4 arcsec). Accurate astrometric alignment allows a detailed comparison between these data and published HST PC Halpha and [Oiii] images. Thermal radio sources coincide with the two proplyds and originate in the ionized photoevaporating flows seen in the optical emission lines. Flow velocities of approx 50 km/s from the ionized proplyd surfaces and \\geq 100 km/s from a possible micro-jet have been detected using the Manchester Echelle spectrometer. A third radio source is found to coincide with a region of extended, high excitation, optical line emission that lies between the binary proplyds 168--326SE/326NW . This is modelled as a bowshock due to the collision of the photoevaporating flows from the two proplyds. Both a thermal and a non-thermal origin for the radio emission in...

  20. A Solar-type Stellar Companion to a Deep Contact Binary in a Quadruple System

    CERN Document Server

    Zhou, X; Zhang, J; Jiang, L -Q; Zhang, B; Kreiner, J

    2016-01-01

    The four-color ($B$ $V$ $R_c$ $I_c$) light curves of V776 Cas are presented and analyzed using the Wilson-Devinney (W-D) method. It is discovered that V776 Cas is an early F-type (F2V) overcontact binary with a very high contact degree ($ f=64.6\\,\\%$) and an extremely low mass ratio ($q=0.130$), which indicate that it is at the final evolutionary stage of cool short-period binaries. The mass of the primary and secondary stars are calculated to be $M_1 = 1.55(\\pm0.04)M_\\odot$, $M_2 = 0.20(\\pm0.01)M_\\odot$. V776 Cas is supposed to be formed from an initially detached binary system via the loss of angular momentum due to the magnetic wind. The initial mass of the present primary and secondary components are calculated to be $M_{1i} = 0.86(\\pm0.10)M_\\odot$ and $M_{2i} = 2.13(\\pm0.04)M_\\odot$. The observed-calculated ($O$-$C$) curve exhibits a cyclic period variation, which is due to the light-travel time effect (LTTE) caused by the presence of a third component with a period of 23.7 years. The mass of the third c...

  1. The tidally induced warping, precession and truncation of accretion discs in binary systems three dimensional simulations

    CERN Document Server

    Larwood, J D; Papaloizou, J C B; Terquem, C

    1996-01-01

    We present the results of non linear, hydrodynamic simulations, in three dimensions, of the tidal perturbation of accretion discs in binary systems where the orbit is circular and not necessarily coplanar with the disc mid-plane. The accretion discs are assumed to be geometrically thin, and of low mass relative to the stellar mass so that they are governed by thermal pressure and viscosity, but not self-gravity. The parameters that we consider in our models are the ratio of the orbital distance to the disc radius, D/R, the binary mass ratio, the initial inclination angle between the orbit and disc planes and the Mach number in the outer parts of the unperturbed disc. For binary mass ratios of around unity and D/R in the range 3 to 4, we find that the global evolution of the discs is governed primarily by the value of the Mach number. For relatively low Mach numbers (i.e. 10 to 20) we find that the discs develop a mildly warped structure, are tidally truncated, and undergo a near rigid body precession at a rat...

  2. Evolution of warped and twisted accretion discs in close binary systems

    CERN Document Server

    Fragner, Moritz

    2009-01-01

    We aim to examine the detailed disc structure that arises in a misaligned binary system as a function of the disc aspect ratio h, viscosity parameter alpha, disc outer radius R, and binary inclination angle gamma_F. We also aim to examine the conditions that lead to an inclined disc being disrupted by strong differential precession. We use a grid-based hydrodynamic code to perform 3D simulations. This code has a relatively low numerical viscosity compared with the SPH schemes that have been used previously to study inclined discs. This allows the influence of viscosity on the disc evolution to be tightly controlled. We find that for thick discs (h=0.05) with low alpha, efficient warp communication in the discs allows them to precess as rigid bodies with very little warping or twisting. Such discs are observed to align with the binary orbit plane on the viscous evolution time. Thinner discs with higher viscosity, in which warp communication is less efficient, develop significant twists before achieving a state...

  3. Discovery of an X-Ray-emitting Contact Binary System 2MASS J11201034-2201340

    Science.gov (United States)

    Hu, Chin-Ping; Yang, Ting-Chang; Chou, Yi; Liu, L.; Qian, S.-B.; Hui, C. Y.; Kong, Albert K. H.; Lin, L. C. C.; Tam, P. H. T.; Li, K. L.; Ngeow, Chow-Choong; Chen, W. P.; Ip, Wing-Huen

    2016-06-01

    We report the detection of orbital modulation, a model solution, and the X-ray properties of a newly discovered contact binary, Two Micron All Sky Survey (2MASS) J11201034-2201340. We serendipitously found this X-ray point source outside the error ellipse when searching for possible X-ray counterparts of γ-ray millisecond pulsars among the unidentified objects detected by the Fermi Gamma-ray Space Telescope. The optical counterpart of the X-ray source (unrelated to the γ-ray source) was then identified using archival databases. The long-term Catalina Real-Time Transient Survey detected a precise signal with a period of P=0.28876208(56) days. A follow-up observation made by the Super Light Telescope of Lulin Observatory revealed the binary nature of the object. Utilizing archived photometric data of multi-band surveys, we construct the spectral energy distribution (SED), which is well fit by a K2V spectral template. The fitting result of the orbital profile using the Wilson-Devinney code suggests that 2MASS J11201034-2201340 is a short-period A-type contact binary and the more massive component has a cool spot. The X-ray emission was first noted in observations made by Swift, and then further confirmed and characterized by an XMM-Newton observation. The X-ray spectrum can be described by a power law or thermal Bremsstrahlung. Unfortunately, we could not observe significant X-ray orbital modulation. Finally, according to the SED, this system is estimated to be 690 pc from Earth with a calculated X-ray intensity of (0.7-1.5)× {10}30 erg s-1, which is in the expected range of an X-ray emitting contact binary.

  4. New Results for Two Optically Faint Low Mass X-Ray Binary Systems

    OpenAIRE

    Wachter, Stefanie

    1997-01-01

    We present optical photometry of the low mass X-ray binary systems GX 349+2 and Ser X-1. Extensive VRI photometry of the faint optical counterpart (V=18.4) to GX 349+2 reveals a period of 22.5 +/- 0.1 h and half-amplitude 0.2 mag. This result confirms and extends our previously reported 22 h period. No color change is detected over the orbit, although the limits are modest. We also report the discovery of two new variable stars in the field of GX 349+2, including a probable W UMa system. Ser ...

  5. A Hot Spot and Mass Transfer of the Algol-type Binary System WZ Crv

    CERN Document Server

    Virnina, Natalia A; Mogorean, Maxim V

    2011-01-01

    We present the results of two color VR observation of the Algol-type binary system WZ Crv (12h44m15.19s, -21d25m35.4s) which were obtained using the remotely controlled telescope TOA-150 of Tzec Maun Observatory. We determined the moments of individual minima, the orbital period and its derivative, the initial epoch, color indices V-R and temperature estimates of the components. Also we noticed that the phase curve is asymmetric: the second maximum is higher than the first one. It indicates that there is a spot in the photosphere of one of the stars in this system.

  6. Photometric Observation and Light Curve Analysis of Binary System ER-Orionis

    Indian Academy of Sciences (India)

    M. M. Lame’e; B. Javanmardi; N. Riazi

    2010-06-01

    Photometric observations of the over-contact binary ER ORI were performed during November 2007 and February to April 2008 with the 51 cm telescope of Biruni Observatory of Shiraz University in U, B and V filters (Johnson system) and an RCA 4509 photomultiplier. We used these data to obtain the light curves and calculate the newtimes of minimum light in each filter and plot the O–C diagram of ER ORI. Using the Wilson’s computer code with the help of an auxiliary computer program to improve the optimizations, the light curve analyses were carried out to find out the photometric elements of the system.

  7. Diamonds in HD 97048

    CERN Document Server

    Habart, E; Natta, A; Carbillet, M

    2004-01-01

    We present adaptive optics high angular resolution ($\\sim0\\farcs$1) spectroscopic observations in the 3 $\\mu$m region of the Herbig Ae/Be star HD 97048. For the first time, we spatially resolve the emission in the diamond features at 3.43 and 3.53 $\\mu$m and in the adjacent continuum. Using both the intensity profiles along the slit and reconstructed two-dimensional images of the object, we derive full-width at half-maximum sizes consistent with the predictions for a circumstellar disk seen pole-on. The diamond emission originates in the inner region ($R \\lesssim 15$ AU) of the disk.

  8. Photometric solution and period analysis of the contact binary system AH Cnc

    Science.gov (United States)

    Peng, Ying-Jiang; Luo, Zhi-Quan; Zhang, Xiao-Bin; Deng, Li-Cai; Wang, Kun; Tian, Jian-Feng; Yan, Zheng-Zhou; Pan, Yang; Fang, Wei-Jing; Feng, Zhong-Wen; Tang, De-Lin; Liu, Qi-Li; Sun, Jin-Jiang; Zhou, Qiang

    2016-10-01

    Photometric observations of AH Cnc, a W UMa-type system in the open cluster M67, were carried out by using the 50BiN telescope. About 100 h of time-series B- and V -band data were taken, based on which eight new times of light minima were determined. By applying the Wilson-Devinney method, the light curves were modeled and a revised photometric solution of the binary system was derived. We confirmed that AH Cnc is a deep contact (f = 51%), low mass-ratio (q = 0.156) system. Adopting the distance modulus derived from study of the host cluster, we have re-calculated the physical parameters of the binary system, namely the masses and radii. The masses and radii of the two components were estimated to be respectively 1.188(±0.061) M ⊙, 1.332(±0.063) R ⊙ for the primary component and 0.185(±0.032) M ⊙, 0.592(±0.051) R ⊙ for the secondary. By adding the newly derived minimum timings to all the available data, the period variations of AH Cnc were studied. This shows that the orbital period of the binary is continuously increasing at a rate of dp/dt = 4.29 × 10‑10 d yr‑1. In addition to the long-term period increase, a cyclic variation with a period of 35.26 yr was determined, which could be attributed to an unresolved tertiary component of the system.

  9. EPIC 220204960: A Quadruple Star System Containing Two Strongly Interacting Eclipsing Binaries

    Science.gov (United States)

    Rappaport, S.; Vanderburg, A.; Borkovits, T.; Kalomeni, B.; Halpern, J. P.; Ngo, H.; Mace, G. N.; Fulton, B. J.; Howard, A. W.; Isaacson, H.; Petigura, E. A.; Mawet, D.; Kristiansen, M. H.; Jacobs, T. L.; LaCourse, D.; Bieryla, A.; Forgács-Dajka, E.; Nelson, L.

    2017-01-01

    We present a strongly interacting quadruple system associated with the K2 target EPIC 220204960. The K2 target itself is a Kp = 12.7 magnitude star at Teff ≃ 6100 K which we designate as "B-N" (blue northerly image). The host of the quadruple system, however, is a Kp ≃ 17 magnitude star with a composite M-star spectrum, which we designate as "R-S" (red southerly image). With a 3.2″ separation and similar radial velocities and photometric distances, `B-N' is likely physically associated with `R-S', making this a quintuple system, but that is incidental to our main claim of a strongly interacting quadruple system in `R-S'. The two binaries in `R-S' have orbital periods of 13.27 d and 14.41 d, respectively, and each has an inclination angle of ≳ 89°. From our analysis of radial velocity measurements, and of the photometric lightcurve, we conclude that all four stars are very similar with masses close to 0.4 M⊙. Both of the binaries exhibit significant ETVs where those of the primary and secondary eclipses `diverge' by 0.05 days over the course of the 80-day observations. Via a systematic set of numerical simulations of quadruple systems consisting of two interacting binaries, we conclude that the outer orbital period is very likely to be between 300 and 500 days. If sufficient time is devoted to RV studies of this faint target, the outer orbit should be measurable within a year.

  10. Tracking Advanced Planetary Systems (TAPAS) with HARPS-N. III. HD 5583 and BD+15 2375 - two cool giants with warm companions

    Science.gov (United States)

    Niedzielski, A.; Villaver, E.; Nowak, G.; Adamów, M.; Kowalik, K.; Wolszczan, A.; Deka-Szymankiewicz, B.; Adamczyk, M.; Maciejewski, G.

    2016-04-01

    Context. Evolved stars are crucial pieces for our understanding of the dependency of the planet formation mechanism on the stellar mass and for exploring the mechanism involved in star-planet interactions more deeply. Over the last ten years, we have monitored about 1000 evolved stars for radial velocity variations in the search for low-mass companions under the Penn State - Torun Centre for Astronomy Planet Search program with the Hobby-Eberly Telescope (HET). Selected prospective candidates that required higher RV precision measurements were followed with HARPS-N at the 3.6 m Telescopio Nazionale Galileo under the TAPAS project. Aims: We aim to detect planetary systems around evolved stars to be able to build sound statistics on the frequency and intrinsic nature of these systems, and to deliver in-depth studies of selected planetary systems with evidence of star-planet interaction processes. Methods: For HD 5583 we obtained 14 epochs of precise RV measurements that were collected over 2313 days with the HET, and 22 epochs of ultra-precise HARPS-N data collected over 976 days. For BD+15 2375 we collected 24 epochs of HET data over 3286 days and 25 epochs of HARPS-S data over 902 days. Results: We report the discovery of two planetary mass objects that are orbiting two evolved red giant stars: HD 5583 has a msini = 5.78MJ companion at 0.529 AU in a nearly circular orbit (e = 0.076), the closest companion to a giant star detected with the RV technique, and BD+15 2735 that, with a msini = 1.06MJ, holds the record for the lightest planet orbiting an evolved star found so far (in a circular e = 0.001, 0.576 AU orbit). These are the third and fourth planets found within the TAPAS project, a HARPS-N monitoring of evolved planetary systems identified with the HET. Based on observations obtained with the Hobby-Eberly Telescope, which is a joint project of the University of Texas at Austin, the Pennsylvania State University, Stanford University, Ludwig

  11. Searching for twins of the V1309 Sco progenitor system: a selection of long-period contact binaries

    CERN Document Server

    Kurtenkov, Alexander

    2016-01-01

    The only well-studied red nova progenitor (V1309 Sco) was a contact binary with a 1.4-day period. The prospects for searching for similar systems, as well as stellar merger candidates in general, are explored in this work. The photospheric temperatures of 128 variables with periods P = 1.1 - 1.8 d classified as W UMa-type binaries are calculated using their colors listed in the SDSS catalog. A selection of 15 contact binaries with similar temperatures and periods as the V1309 Sco progenitor is thus compiled. The Kepler Eclipsing Binary Catalog is used to analyse systems with eclipse timing variations (ETV) possibly caused by changes of the orbital period. Out of the 31 systems with parabolic ETV curves listed by Conroy et al. (2014, AJ, 147, 45) two could be contact binaries with a decreasing period and, therefore, potential stellar merger candidates. Out of the 569 contact binaries in the OGLE field analysed by Kubiak et al. (2006, AcA, 56, 253) 14 systems have periods longer than 0.8 d and a statistically s...

  12. A close-pair binary in a distant triple supermassive black hole system.

    Science.gov (United States)

    Deane, R P; Paragi, Z; Jarvis, M J; Coriat, M; Bernardi, G; Fender, R P; Frey, S; Heywood, I; Klöckner, H-R; Grainge, K; Rumsey, C

    2014-07-03

    Galaxies are believed to evolve through merging, which should lead to some hosting multiple supermassive black holes. There are four known triple black hole systems, with the closest black hole pair being 2.4 kiloparsecs apart (the third component in this system is at 3 kiloparsecs), which is far from the gravitational sphere of influence (about 100 parsecs for a black hole with mass one billion times that of the Sun). Previous searches for compact black hole systems concluded that they were rare, with the tightest binary system having a separation of 7 parsecs (ref. 10). Here we report observations of a triple black hole system at redshift z = 0.39, with the closest pair separated by about 140 parsecs and significantly more distant from Earth than any other known binary of comparable orbital separation. The effect of the tight pair is to introduce a rotationally symmetric helical modulation on the structure of the large-scale radio jets, which provides a useful way to search for other tight pairs without needing extremely high resolution observations. As we found this tight pair after searching only six galaxies, we conclude that tight pairs are more common than hitherto believed, which is an important observational constraint for low-frequency gravitational wave experiments.

  13. Discovery And Characterization of Wide Binary Systems With a Very Low Mass Component

    CERN Document Server

    Baron, Frédérique; Artigau, Étienne; Doyon, René; Gagné, Jonathan; Davison, Cassy L; Malo, Lison; Robert, Jasmin; Nadeau, Daniel; Reylé, Céline

    2015-01-01

    We report the discovery of 14 low-mass binary systems containing mid-M to mid-L dwarf companions with separations larger than 250 AU. We also report the independent discovery of 9 other systems with similar characteristics that were recently discovered in other studies. We have identified these systems by searching for common proper motion sources in the vicinity of known high proper motion stars, based on a cross-correlation of wide area near-infrared surveys (2MASS, SDSS, and SIMP). An astrometric follow-up, for common proper motion confirmation, was made with SIMON and/or CPAPIR at the OMM 1.6 m and CTIO 1.5 m telescopes for all the candidates identified. A spectroscopic follow-up was also made with GMOS or GNIRS at Gemini to determine the spectral types of 11 of our newly identified companions and 10 of our primaries. Statistical arguments are provided to show that all of the systems we report here are very likely to be physical binaries. One of the new systems reported features a brown dwarf companion: L...

  14. Asteroid flux towards circumprimary habitable zones in binary star systems: II. Dynamics

    CERN Document Server

    Bancelin, D; Bazso, A

    2015-01-01

    Secular and mean motion resonances (hearafter MMR) are effective perturbations to shape planetary systems. In binary star systems, they play a key role during the early and late phases of planetary formation as well as the dynamical stability of a planetary system. In this study, we aim to correlate the presence of orbital resonances with the rate of icy asteroids crossing the habitable zone (hearafter HZ), from a circumprimary disk of planetesimals in various binary star systems. We modelled a belt of small bodies in the inner and outer regions, respectively below and beyond the orbit of a gas giant planet. The planetesimals are equally placed around a primary G-type star and move under the gravitational influence of the two stars and the gas giant. We numerically integrated the system for 50 Myr considering various parameters for the secondary star. Its stellar type varies from a M- to F-type; its semimajor axis is either 50 au or 100 au and its eccentricity is either 0.1 or 0.3. Our simulations highlight t...

  15. A Search For X-ray Emission From Colliding Magnetospheres In Young Eccentric Stellar Binaries

    CERN Document Server

    Getman, Konstantin V; Kospal, Agnes; Salter, Demerese M; Garmire, Gordon P

    2016-01-01

    Among young binary stars whose magnetospheres are expected to collide, only two systems have been observed near periastron in the X-ray band: the low-mass DQ Tau and the older and more massive HD 152404. Both exhibit elevated levels of X-ray emission at periastron. Our goal is to determine whether colliding magnetospheres in young high-eccentricity binaries commonly produce elevated average levels of X-ray activity. This work is based on Chandra snapshots of multiple periastron and non-periastron passages in four nearby young eccentric binaries (Parenago 523, RX J1622.7-2325 Nw, UZ Tau E, and HD 152404). We find that for the merged sample of all 4 binaries the current X-ray data show an increasing average X-ray flux near periastron (at about 2.5-sigma level). Further comparison of these data with the X-ray properties of hundreds of young stars in the Orion Nebula Cluster, produced by the Chandra Orion Ultradeep Project (COUP), indicates that the X-ray emission from the merged sample of our binaries can not be...

  16. MODELING VAPOR LIQUID EQUILIBRIUM OF IONIC LIQUIDS plus GAS BINARY SYSTEMS AT HIGH PRESSURE WITH CUBIC EQUATIONS OF STATE

    OpenAIRE

    Freitas, ACD; Cunico, LP; M. Aznar; Guirardello,R.

    2013-01-01

    Ionic liquids (IL) have been described as novel environmentally benign solvents because of their remarkable characteristics. Numerous applications of these solvents continue to grow at an exponential rate. In this work, high pressure vapor liquid equilibria for 17 different IL + gas binary systems were modeled at different temperatures with Peng-Robinson (PR) and Soave-Redlich-Kwong (SRK) equations of state, combined with the van der Waals mixing rule with two binary interaction parameters (v...

  17. EVIDENCE FOR THE DIRECT DETECTION OF THE THERMAL SPECTRUM OF THE NON-TRANSITING HOT GAS GIANT HD 88133 b

    KAUST Repository

    Piskorz, Danielle

    2016-11-23

    We target the thermal emission spectrum of the non-transiting gas giant HD 88133 b with high-resolution near-infrared spectroscopy, by treating the planet and its host star as a spectroscopic binary. For sufficiently deep summed flux observations of the star and planet across multiple epochs, it is possible to resolve the signal of the hot gas giant\\'s atmosphere compared to the brighter stellar spectrum, at a level consistent with the aggregate shot noise of the full data set. To do this, we first perform a principal component analysis to remove the contribution of the Earth\\'s atmosphere to the observed spectra. Then, we use a cross-correlation analysis to tease out the spectra of the host star and HD 88133 b to determine its orbit and identify key sources of atmospheric opacity. In total, six epochs of Keck NIRSPEC L-band observations and three epochs of Keck NIRSPEC K-band observations of the HD 88133 system were obtained. Based on an analysis of the maximum likelihood curves calculated from the multi-epoch cross-correlation of the full data set with two atmospheric models, we report the direct detection of the emission spectrum of the non-transiting exoplanet HD 88133 b and measure a radial projection of the Keplerian orbital velocity of 40 +/- 15 km s(-1), a true mass of 1.02(-0.28)(+0.61) M-J, a nearly face-on orbital inclination of 15(-5)(+60), and an atmosphere opacity structure at high dispersion dominated by water vapor. This, combined with 11 years of radial velocity measurements of the system, provides the most up-to-date ephemeris for HD 88133.

  18. Tracking Advanced Planetary Systems (TAPAS) with HARPS-N. III. HD 5583 and BD+15 2375 - two cool giants with warm companions

    CERN Document Server

    Niedzielski, A; Nowak, G; Adamów, M; Kowalik, K; Wolszczan, A; Deka-Szymankiewicz, B; Adamczyk, M; Maciejewski, G

    2016-01-01

    Evolved stars are crucial pieces to understand the dependency of the planet formation mechanism on the stellar mass and to explore deeper the mechanism involved in star-planet interactions. Over the past ten years, we have monitored about 1000 evolved stars for radial velocity variations in search for low-mass companions under the Penn State - Torun Centre for Astronomy Planet Search program with the Hobby-Eberly Telescope. Selected prospective candidates that required higher RV precision measurements have been followed with HARPS-N at the 3.6 m Telescopio Nazionale Galileo under the TAPAS project. We aim to detect planetary systems around evolved stars to be able to build sound statistics on the frequency and intrinsic nature of these systems, and to deliver in-depth studies of selected planetary systems with evidence of star-planet interaction processes. For HD 5583 we obtained 14 epochs of precise RV measurements collected over 2313 days with the Hobby-Eberly Telescope (HET), and 22 epochs of ultra-precise...

  19. First light of the VLT planet finder SPHERE - II. The physical properties and the architecture of the young systems PZ Tel and HD 1160 revisited

    CERN Document Server

    Maire, A -L; Ginski, C; Vigan, A; Messina, S; Mesa, D; Galicher, R; Gratton, R; Desidera, S; Kopytova, T G; Millward, M; Thalmann, C; Claudi, R U; Ehrenreich, D; Zurlo, A; Chauvin, G; Antichi, J>; Baruffolo, A; Bazzon, A; Beuzit, J -L; Blanchard, P; Boccaletti, A; de Boer, J; Carle, M; Cascone, E; Costille, A; De Caprio, V; Delboulbe, A; Dohlen, K; Dominik, C; Feldt, M; Fusco, T; Girard, J H; Giro, E; Gisler, D; Gluck, L; Gry, C; Henning, T; Hubin, N; Hugot, E; Jaquet, M; Kasper, M; Lagrange, A -M; Langlois, M; Mignant, D Le; Llored, M; Madec, F; Martinez, P; Mawet, D; Milli, J; Moeller-Nilsson, O; Mouillet, D; Moulin, T; Moutou, C; Origne, A; Pavlov, A; Petit, C; Pragt, J; Puget, P; Ramos, J; Rochat, S; Roelfsema, R; Salasnich, B; Sauvage, J -F; Schmid, H M; Turatto, M; Udry, S; Vakili, F; Wahhaj, Z; Weber, L; Wildi, F

    2015-01-01

    [Abridged] Context. The young systems PZ Tel and HD 1160, hosting known low-mass companions, were observed during the commissioning of the new planet finder SPHERE with several imaging and spectroscopic modes. Aims. We aim to refine the physical properties and architecture of both systems. Methods. We use SPHERE commissioning data and REM observations, as well as literature and unpublished data from VLT/SINFONI, VLT/NaCo, Gemini/NICI, and Keck/NIRC2. Results. We derive new photometry and confirm the nearly daily photometric variability of PZ Tel A. Using literature data spanning 38 yr, we show that the star also exhibits a long-term variability trend. The 0.63-3.8 mic SED of PZ Tel B allows us to revise its properties: spectral type M7+/-1, Teff=2700+/-100 K, log(g)0.66) of PZ Tel B. For e4 MJ) outside 0.5" for the PZ Tel system. We also show that K1-K2 color can be used with YJH low-resolution spectra to identify young L-type companions, provided high photometric accuracy (<0.05 mag) is achieved. Conclusi...

  20. The HARPS search for southern extra-solar planets. XXVII. Up to seven planets orbiting HD 10180: probing the architecture of low-mass planetary systems

    CERN Document Server

    Lovis, C; Mayor, M; Udry, S; Benz, W; Bertaux, J -L; Bouchy, F; Correia, A C M; Laskar, J; Curto, G Lo; Mordasini, C; Pepe, F; Queloz, D; Santos, N C

    2010-01-01

    Context. Low-mass extrasolar planets are presently being discovered at an increased pace by radial velocity and transit surveys, opening a new window on planetary systems. Aims. We are conducting a high-precision radial velocity survey with the HARPS spectrograph which aims at characterizing the population of ice giants and super-Earths around nearby solar-type stars. This will lead to a better understanding of their formation and evolution, and yield a global picture of planetary systems from gas giants down to telluric planets. Methods. Progress has been possible in this field thanks in particular to the sub-m/s radial velocity precision achieved by HARPS. We present here new high-quality measurements from this instrument. Results. We report the discovery of a planetary system comprising at least five Neptune-like planets with minimum masses ranging from 12 to 25 M_Earth, orbiting the solar-type star HD 10180 at separations between 0.06 and 1.4 AU. A sixth radial velocity signal is present at a longer perio...