ROBERT WILLIAMS Williams, RE 1965

Total Page:16

File Type:pdf, Size:1020Kb

ROBERT WILLIAMS Williams, RE 1965 Bibliography – ROBERT WILLIAMS Williams, R.E. 1965, "The Size of the Solar HII Region," Ap. J., 142, 314. Williams, R.E. 1967, "The Ionization and Thermal Equilibrium of a Gas Excited by Ultraviolet Synchrotron Radiation," Ap. J., 147, 556. Williams, R.E. 1968, "The Ionization of Planetary Nebulae," in IAU Symp. No. 34: Planetary Nebulae, eds. D.E. Osterbrock and C.R. O'Dell (Dordrecht: Reidel), p. 190. Williams, R.E., and Weymann, R.J. 1968, "Calculated Line Intensities for Models of Seyfert Galaxy Nuclei," Astron. J., 73, 895. Williams, R.E. 1968, "The Nuclei of Seyfert Galaxies," A.S.P. Leaflet No. 473. Henry, R.J.W., and Williams, R.E. 1968, "Collision Strengths and Photoionization Cross Sections for Nitrogen, Oxygen, and Neon," Pub. A.S.P., 80, 669. Weymann, R.J., and Williams, R.E. 1969, "The Bowen Fluorescence Mechanism in Planetary Nebulae and the Nuclei of Seyfert Galaxies," Ap. J., 157, 1201. Williams, R.E. 1970, "[O I] 6300 Emission in Planetary Nebulae," Ap. J., 159, 829. Berry, H.G., Bickel, W., Martinson, I., Weymann, R.J., and Williams, R.E. 1970, "Total Transition Probabilities for the Bowen Levels of O III," Ap. Lett., 5, 81. Williams, R.E. 1970, "Absorption Lines in Quasi-Stellar Objects with zabs>zem," Nature, 228, 269. Capriotti, E.R., Cromwell, R.H., and Williams, R.E. 1971, "Observed Small-Scale Structure in Planetary Nebulae," Ap. Lett., 7, 241. Williams, R.E. 1971, "The Helium Abundance in Quasi-Stellar Objects," Ap. J. Lett., 167, L27. Williams, R.E. 1972, "The Effects of Radiation Pressure from Resonance Scattering in a Quasar Cloud," Ap. J., 178, 105. Williams, R.E. 1973, "The Ionization Structure of Planetary Nebulae--X: The Contribution of Charge Exchange and Optically Thick Condensations to [O I] Radiation," M.N.R.A.S., 164, 111. Carswell, R.F., Strittmatter, P.A., Williams, R.E., Kinman, T.D., and Serkowski, K. 1974, "Optical Observations of the Radio Source 0735+178," Ap. J. Lett., 190, L101. Carswell, R.F., Strittmatter, P.A., Williams, R.E., Beaver, E.A., and Harms, R. 1975, "The Spectrum of OH 471 (0642+44)," Ap. J., 195, 269. Steigman, G., Strittmatter, P.A., and Williams, R.E. 1975, "The COPERNICUS Observations: Interstellar or Circumstellar Material?," Ap. J., 198, 575. Williams, R.E., Strittmatter, P.A., Carswell, R.F., and Craine, E.R. 1975, "Splitting of Absorption Lines in 3C 191," Ap. J., 202, 296. Coleman, G., Carswell, R.F., Strittmatter, P.A., Williams, R.E., Baldwin, J.A., Robinson, L.B., and Wampler, E.J. 1976, "The Spectrum of the QSO PHL 957," Ap. J., 207, 1. Williams, R.E., and Weymann, R.J. 1976, "The Absorption Spectrum of the Quasar PHL 1222," Ap. J. Lett., 207, L143. Strittmatter, P.A., and Williams, R.E. 1976, "The Line Spectra of Quasi-Stellar Objects," Ann. Rev. Astr. Ap., 14, 307. Williams, R.E. 1976, "Gaseous Nebulae," in Lecture Notes on Introductory Theoretical Astrophysics, ed. R.J. Weymann (Tucson: Pachart Publ.), chap. 3. Carswell, R.F., Coleman, G., Strittmatter, P.A., and Williams, R.E. 1976, "Absorption-Line QSOs," Astron. Astrophys., 53, 275. Weymann, R.J., Williams, R.E., Beaver, E.A., and Miller, J.S. 1977, "A Spectroscopic Study of Selected Quasars with zabs>zem," Ap. J., 213, 619. Burbidge, E.M., Smith, H.E., Weymann, R.J., and Williams, R.E. 1977, "Observations of Fe II and Mg II Absorption in QSOs with zabs << zem," Ap. J., 218, 1. Peterson, B.M., Coleman, G.D., Strittmatter, P.A., and Williams, R.E. 1977, "Absorption by Neutral Hydrogen and Ionized Magnesium in Quasi-Stellar Objects and BL Lacertae Objects," Ap. J., 218, 605. Williams, R.E. 1977, "Element Abundance Analyses of Novae," in IAU Colloq. No. 42: The Interaction of Variable Stars with their Environment, eds. R. Kippenhahn, J. Rahe, and W. Strohmeier (Bamberg: Remeis-Sternwarte), p. 242. Weymann, R.J., and Williams, R.E. 1978, "A Summary of the Properties of zabs>zem Systems and Some Comments on the Origins of QSO Absorption-Line Systems," Physica Scripta, 17, 217. Harms, R.J., Strittmatter, P.A., and Williams, R.E. 1978, "The Far-Ultraviolet Flux from Lambda Orionis A," Ap. J., 223, 234. Wilkerson, M.S., Coleman, G., Gilbert, G., Strittmatter, P.A., Williams, R.E., Baldwin, J.A., Carswell, R.F., and Grandi, S.A. 1978, "The Spectrum of the Quasar B2 1225+31," Ap. J., 223, 364. Adams, M.T., Coleman, G.D., Stockman, H.S., Strittmatter, P.A., and Williams, R.E. 1978, "The Spectrum of Markarian 132," Ap. J., 223, 758. Williams, R.E., Woolf, N.J., Hege, E.K., Moore, R.L., and Kopriva, D.A. 1978, "The Shell Around Nova DQ Herculis 1934," Ap. J., 224, 171. Williams, R.E., and Gallagher, J.S. 1979, "Spectrophotometry of Filaments Surrounding Nova RR Pictoris 1925," Ap. J., 228, 482. Turnshek, D.A., Weymann, R.J., and Williams, R.E. 1979, "Physical Conditions in the Absorbing Regions Associated with the QSO 1756+237," Ap. J., 230, 330. Weymann, R.J., Williams, R.E., Peterson, B.M., and Turnshek, D.A. 1979, "Results of a Homogeneous Survey of Absorption Lines in QSOs of Small and Intermediate Emission Redshift," Ap. J., 234, 33. Williams, R.E. 1980, "Emission Lines from the Accretion Disks of Cataclysmic Variables," Ap. J., 235, 939. Gallagher, J.S., Hege, E.K., Kopriva, D.A., Williams, R.E., and Butcher, H.R. 1980, "Spectrophotometry of the Nebula Surrounding Nova T Aurigae 1891," Ap. J., 237, 55. Turnshek, D.A., Weymann, R.J., Liebert, J.W., Williams, R.E., and Strittmatter, P.A. 1980, "Observations of Three QSOs with Broad, Detached Absorption Features," Ap. J., 238, 488. Williams, R.E. 1981, "The Shells of Novas," Sci. Amer., 244, 120. Williams, R.E., Sparks, W.M., Gallagher, J.S., Ney, E.P., Starrfield, S.G., and Truran, J.W. 1981, "Ultraviolet Spectroscopy of the Recurrent Nova U Scorpii During Outburst," Ap. J., 251, 221. Liebert, J., Stockman, H.S., Williams, R.E., Tapia, S., Green, R.F., Rautenkranz, D., Ferguson, D.H., and Szkody, P. 1982, "PG 1550+191: A New AM Herculis Type Binary System," Ap. J., 256, 594. Williams, R.E., and Ferguson, D.H. 1982, "He I Line Emission and the Helium Abundance in Cataclysmic Variables," Ap. J., 257, 672. Williams, R.E. 1982, "Spectroscopic Analysis of the Extended Shells Around the Novae CP Puppis and T Pyxidis," Ap. J., 261, 170. Sparks, W.M., Starrfield, S., Wyckoff, S., Williams, R.E., Truran, J.W., and Ney, E.P. 1982, "IUE Observations of the 1981 Outburst of Nova CrA," in Advances in Ultraviolet Astronomy, eds. Y. Kondo, J.M. Mead, and R.D. Chapman, NASA Conference Publ. 2238, p. 478. Williams, R.E. 1982, "Novae as Sources of Nitrogen in Galaxies," Ap. J. Lett., 261, L77. Williams, R.E., and Ferguson, D.H. 1983, "The Formation of Optical CNO Emission Lines in Cataclysmic Variables," in IAU Colloq. No. 72: Cataclysmic Variables and Related Objects, eds. M. Livio and G. Shaviv (Dordrecht: Reidel), p. 97. Ferland, G.J., Williams, R.E., Lambert, D.L., Shields, G.A., Slovak, M., Gondhalekar, P.M., and Truran, J.W. 1984, "IUE Observations of DQ Herculis and its Nebula, and the Nature of the Cold Nova Shells," Ap. J., 281, 194. Williams, R.E., and Christiansen, W.A. 1985, "Blast Wave Formation of the Extended Stellar Shells Surrounding Elliptical Galaxies," Ap. J., 291, 80. Williams, R.E. 1985, "CNO Abundances in Novae Ejecta," in Production and Distribution of CNO Elements, eds. I.J. Danziger, F. Matteucci, and K. Kjar (Garching: ESO), p. 225. Williams, R.E., Ney, E.P., Sparks, W.M., Starrfield, S.G., Wyckoff, S., and Truran, J.W. 1985, "Ultraviolet Spectral Evolution and Heavy Element Abundances in Nova Corona Austrinae 1981," M.N.R.A.S., 212, 753. Sion, E.M., Starrfield, S.G., van Steenberg, M.E., Sparks, W., Truran, J.W., and Williams, R.E. 1986, "A High-Resolution IUE Observation of the Line of Sight to Nova V693 Corona Austrinae 1981," Astron. J., 92, 1145. Wilkinson, A., Browne, I.W.A., Kotanyi, C., Christiansen, W.A., and Williams, R.E. 1987, "Radio Emission from Shell Elliptical Galaxies," M.N.R.A.S., 224, 895. Williams, R.E., Phillips, M.M., and Heathcote, S.R. 1987, "Hydrogen Depletion and the Evolution of Cataclysmic Variables to Low-Mass X- Ray Binaries," Ap. Sp. Sci., 131, 681. Blanco, V.M., Gregory, B., Hamuy, M., Heathcote, S.R., Phillips, M.M., Suntzeff, N.B., Terndrup, D.M., Walker, A.R., and Williams, R.E. 1987, "Supernova 1987A in the Large Magellanic Cloud: Initial Observations at Cerro Tololo," Ap. J., 320, 589. Williams, R.E. 1987, "Supernova 1987A in the Large Magellanic Cloud: Possible s-Process Enhancements in the Progenitor," Ap. J. Lett., 320, L117. Baldwin, J.A., McMahon, R., Hazard, C., and Williams, R.E. 1988, "QSOs with Narrow Emission Lines," Ap. J., 327, 103. Lin, D.N.C., Williams, R.E., and Stover, R.J. 1988, "Stark Broadened Emission Lines in the Accretion Disks of Cataclysmic Variables," Ap. J., 327, 234. Williams, R.E. 1988, "Observations of SN1987A from Cerro Tololo," Kagaku, 58, 239. Williams, R.E. 1988, "Enrichment of s-Process Elements in the Progenitor of SN1987A," in IAU Colloq. No. 108: Atmospheric Diagnostics of Stellar Evolution - Chemical Peculiarity, Mass Loss, and Explosion, ed. K. Nomoto (Berlin: Springer-Verlag), p. 274. Elias, J.H., Gregory, B., Phillips, M.M., Williams, R.E., Graham, J.R., Meikle, W.P.S., Schwartz, R.D., and Wilking, B.
Recommended publications
  • Unknown Amorphous Carbon II. LRS SPECTRA the Sample Consists Of
    Table I A summary of the spectral -features observed in the LRS spectra of the three groups o-f carbon stars. The de-finition o-f the groups is given in the text. wavelength Xmax identification Group I B - 12 urn E1 9.7 M™ Silicate 12 - 23 jim E IB ^m Silicate Group II < 8.5 M"i A C2H2 CS? 12 - 16 f-i/n A 13.7 - 14 Mm C2H2 HCN? 8 - 10 Mm E 8.6 M"i Unknown 10 - 13 Mm E 11.3 - 11 .7 M«> SiC Group III 10 - 13 MJn E 11.3 - 11 .7 tun SiC B - 23 Htn C Amorphous carbon 1 The letter in this column indicates the nature o-f the -feature: A = absorption; E = emission; C indicates the presence of continuum opacity. II. LRS SPECTRA The sample consists of 304 carbon stars with entries in the LRS catalog (Papers I-III). The LRS spectra have been divided into three groups. Group I consists of nine stars with 9.7 and 18 tun silicate features in their LRS spectra pointing to oxygen-rich dust in the circumstellar shell. These sources are discussed in Paper I. The remaining stars all have spectra with carbon-rich dust features. Using NIR photometry we have shown that in the group II spectra the stellar photosphere is the dominant continuum. The NIR color temperature is of the order of 25OO K. Paper II contains a discussion of sources with this class of spectra. The continuum in the group III spectra is probably due to amorphous carbon dust.
    [Show full text]
  • JOHN R. THORSTENSEN Address
    CURRICULUM VITAE: JOHN R. THORSTENSEN Address: Department of Physics and Astronomy Dartmouth College 6127 Wilder Laboratory Hanover, NH 03755-3528; (603)-646-2869 [email protected] Undergraduate Studies: Haverford College, B. A. 1974 Astronomy and Physics double major, High Honors in both. Graduate Studies: Ph. D., 1980, University of California, Berkeley Astronomy Department Dissertation : \Optical Studies of Faint Blue X-ray Stars" Graduate Advisor: Professor C. Stuart Bowyer Employment History: Department of Physics and Astronomy, Dartmouth College: { Professor, July 1991 { present { Associate Professor, July 1986 { July 1991 { Assistant Professor, September 1980 { June 1986 Research Assistant, Space Sciences Lab., U.C. Berkeley, 1975 { 1980. Summer Student, National Radio Astronomy Observatory, 1974. Summer Student, Bartol Research Foundation, 1973. Consultant, IBM Corporation, 1973. (STARMAP program). Honors and Awards: Phi Beta Kappa, 1974. National Science Foundation Graduate Fellow, 1974 { 1977. Dorothea Klumpke Roberts Award of the Berkeley Astronomy Dept., 1978. Professional Societies: American Astronomical Society Astronomical Society of the Pacific International Astronomical Union Lifetime Publication List * \Can Collapsed Stars Close the Universe?" Thorstensen, J. R., and Partridge, R. B. 1975, Ap. J., 200, 527. \Optical Identification of Nova Scuti 1975." Raff, M. I., and Thorstensen, J. 1975, P. A. S. P., 87, 593. \Photometry of Slow X-ray Pulsars II: The 13.9 Minute Period of X Persei." Margon, B., Thorstensen, J., Bowyer, S., Mason, K. O., White, N. E., Sanford, P. W., Parkes, G., Stone, R. P. S., and Bailey, J. 1977, Ap. J., 218, 504. \A Spectrophotometric Survey of the A 0535+26 Field." Margon, B., Thorstensen, J., Nelson, J., Chanan, G., and Bowyer, S.
    [Show full text]
  • Winter Constellations
    Winter Constellations *Orion *Canis Major *Monoceros *Canis Minor *Gemini *Auriga *Taurus *Eradinus *Lepus *Monoceros *Cancer *Lynx *Ursa Major *Ursa Minor *Draco *Camelopardalis *Cassiopeia *Cepheus *Andromeda *Perseus *Lacerta *Pegasus *Triangulum *Aries *Pisces *Cetus *Leo (rising) *Hydra (rising) *Canes Venatici (rising) Orion--Myth: Orion, the great ​ ​ hunter. In one myth, Orion boasted he would kill all the wild animals on the earth. But, the earth goddess Gaia, who was the protector of all animals, produced a gigantic scorpion, whose body was so heavily encased that Orion was unable to pierce through the armour, and was himself stung to death. His companion Artemis was greatly saddened and arranged for Orion to be immortalised among the stars. Scorpius, the scorpion, was placed on the opposite side of the sky so that Orion would never be hurt by it again. To this day, Orion is never seen in the sky at the same time as Scorpius. DSO’s ● ***M42 “Orion Nebula” (Neb) with Trapezium A stellar ​ ​ ​ nursery where new stars are being born, perhaps a thousand stars. These are immense clouds of interstellar gas and dust collapse inward to form stars, mainly of ionized hydrogen which gives off the red glow so dominant, and also ionized greenish oxygen gas. The youngest stars may be less than 300,000 years old, even as young as 10,000 years old (compared to the Sun, 4.6 billion years old). 1300 ly. ​ ​ 1 ● *M43--(Neb) “De Marin’s Nebula” The star-forming ​ “comma-shaped” region connected to the Orion Nebula. ● *M78--(Neb) Hard to see. A star-forming region connected to the ​ Orion Nebula.
    [Show full text]
  • Variable Star Section Circular No
    The British Astronomical Association Variable Star Section Circular No. 176 June 2018 Office: Burlington House, Piccadilly, London W1J 0DU Contents Joint BAA-AAVSO meeting 3 From the Director 4 V392 Per (Nova Per 2018) - Gary Poyner & Robin Leadbeater 7 High-Cadence measurements of the symbiotic star V648 Car using a CMOS camera - Steve Fleming, Terry Moon and David Hoxley 9 Analysis of two semi-regular variables in Draco – Shaun Albrighton 13 V720 Cas and its close companions – David Boyd 16 Introduction to AstroImageJ photometry software – Richard Lee 20 Project Melvyn, May 2018 update – Alex Pratt 25 Eclipsing Binary news – Des Loughney 27 Summer Eclipsing Binaries – Christopher Lloyd 29 68u Herculis – David Conner 36 The BAAVSS Eclipsing Binary Programme lists – Christopher Lloyd 39 Section Publications 42 Contributing to the VSSC 42 Section Officers 43 Cover image V392 Per (Nova Per 2018) May 6.129UT iTelescope T11 120s. Martin Mobberley 2 Back to contents Joint BAA/AAVSO Meeting on Variable Stars Warwick University Saturday 7th & Sunday 8th July 2018 Following the last very successful joint meeting between the BAAVSS and the AAVSO at Cambridge in 2008, we are holding another joint meeting at Warwick University in the UK on 7-8 July 2018. This two-day meeting will include talks by Prof Giovanna Tinetti (University College London) Chemical composition of planets in our Galaxy Prof Boris Gaensicke (University of Warwick) Gaia: Transforming Stellar Astronomy Prof Tom Marsh (University of Warwick) AR Scorpii: a remarkable highly variable
    [Show full text]
  • Astronomy Binder
    Astronomy Binder Bloomington High School South 2011 Contents 1 Astronomical Distances 2 1.1 Geometric Methods . 2 1.2 Spectroscopic Methods . 4 1.3 Standard Candle Methods . 4 1.4 Cosmological Redshift . 5 1.5 Distances to Galaxies . 5 2 Age and Size 6 2.1 Measuring Age . 6 2.2 Measuring Size . 7 3 Variable Stars 7 3.1 Pulsating Variable Stars . 7 3.1.1 Cepheid Variables . 7 3.1.2 RR Lyrae Variables . 8 3.1.3 RV Tauri Variables . 8 3.1.4 Long Period/Semiregular Variables . 8 3.2 Binary Variables . 8 3.3 Cataclysmic Variables . 11 3.3.1 Classical Nova . 11 3.3.2 Recurrent Novae . 11 3.3.3 Dwarf Novae (U Geminorum) . 11 3.3.4 X-Ray Binary . 11 3.3.5 Polar (AM Herculis) star . 12 3.3.6 Intermediate Polar (DQ Herculis) star . 12 3.3.7 Super Soft Source (SSS) . 12 3.3.8 VY Sculptoris stars . 12 3.3.9 AM Canum Venaticorum stars . 12 3.3.10 SW Sextantis stars . 13 3.3.11 Symbiotic Stars . 13 3.3.12 Pulsating White Dwarfs . 13 4 Galaxy Classification 14 4.1 Elliptical Galaxies . 14 4.2 Spirals . 15 4.3 Classification . 16 4.4 The Milky Way Galaxy (MWG . 19 4.4.1 Scale Height . 19 4.4.2 Magellanic Clouds . 20 5 Galaxy Interactions 20 6 Interstellar Medium 21 7 Active Galactic Nuclei 22 7.1 AGN Equations . 23 1 8 Spectra 25 8.1 21 cm line . 26 9 Black Holes 26 9.1 Stellar Black Holes .
    [Show full text]
  • Fy10 Budget by Program
    AURA/NOAO FISCAL YEAR ANNUAL REPORT FY 2010 Revised Submitted to the National Science Foundation March 16, 2011 This image, aimed toward the southern celestial pole atop the CTIO Blanco 4-m telescope, shows the Large and Small Magellanic Clouds, the Milky Way (Carinae Region) and the Coal Sack (dark area, close to the Southern Crux). The 33 “written” on the Schmidt Telescope dome using a green laser pointer during the two-minute exposure commemorates the rescue effort of 33 miners trapped for 69 days almost 700 m underground in the San Jose mine in northern Chile. The image was taken while the rescue was in progress on 13 October 2010, at 3:30 am Chilean Daylight Saving time. Image Credit: Arturo Gomez/CTIO/NOAO/AURA/NSF National Optical Astronomy Observatory Fiscal Year Annual Report for FY 2010 Revised (October 1, 2009 – September 30, 2010) Submitted to the National Science Foundation Pursuant to Cooperative Support Agreement No. AST-0950945 March 16, 2011 Table of Contents MISSION SYNOPSIS ............................................................................................................ IV 1 EXECUTIVE SUMMARY ................................................................................................ 1 2 NOAO ACCOMPLISHMENTS ....................................................................................... 2 2.1 Achievements ..................................................................................................... 2 2.2 Status of Vision and Goals ................................................................................
    [Show full text]
  • METEOR CSILLAGÁSZATI ÉVKÖNYV 2019 Meteor Csillagászati Évkönyv 2019
    METEOR CSILLAGÁSZATI ÉVKÖNYV 2019 meteor csillagászati évkönyv 2019 Szerkesztette: Benkő József Mizser Attila Magyar Csillagászati Egyesület www.mcse.hu Budapest, 2018 Az évkönyv kalendárium részének összeállításában közreműködött: Tartalom Bagó Balázs Görgei Zoltán Kaposvári Zoltán Kiss Áron Keve Kovács József Bevezető ....................................................................................................... 7 Molnár Péter Sánta Gábor Kalendárium .............................................................................................. 13 Sárneczky Krisztián Szabadi Péter Cikkek Szabó Sándor Szőllősi Attila Zsoldos Endre: 100 éves a Nemzetközi Csillagászati Unió ........................191 Zsoldos Endre Maria Lugaro – Kereszturi Ákos: Elemkeletkezés a csillagokban.............. 203 Szabó Róbert: Az OGLE égboltfelmérés 25 éve ........................................218 A kalendárium csillagtérképei az Ursa Minor szoftverrel készültek. www.ursaminor.hu Beszámolók Mizser Attila: A Magyar Csillagászati Egyesület Szakmailag ellenőrizte: 2017. évi tevékenysége .........................................................................242 Szabados László Kiss László – Szabó Róbert: Az MTA CSFK Csillagászati Intézetének 2017. évi tevékenysége .........................................................................248 Petrovay Kristóf: Az ELTE Csillagászati Tanszékének működése 2017-ben ............................................................................ 262 Szabó M. Gyula: Az ELTE Gothard Asztrofi zikai Obszervatórium
    [Show full text]
  • The Orbital Ephemeris of the Classical Nova RR Pictoris: Presence of A
    Draft version August 5, 2018 Preprint typeset using LATEX style AASTeX6 v. 1.0 THE ORBITAL EPHEMERIS OF THE CLASSICAL NOVA RR PICTORIS: PRESENCE OF A THIRD BODY? N. Vogt1, M. R. Schreiber1, F.-J. Hambsch3,4, G. Retamales1, C. Tappert1, L. Schmidtobreick2 & I. Fuentes-Morales1 1Instituto de F´ısica y Astronom´ıa, Universidad de Valpara´ıso, Valpara´ıso, Chile 2European Southern Observatory, Santiago 19, Chile, Casilla 1900 3Vereniging Voor Sterrenkunde (VVS), Oude Bleken 12, 2400 Mol, Belgium 4 American Association of Variable Star Observers, 49 Bay State Rd., Cambridge, MA02138, USA ABSTRACT The ex-nova RR Pic presents a periodic hump in its light curve which is considered to refer to its orbital period. Analyzing all available epochs of these hump maxima in the literature, and combining them with those from new light curves obtained in 2013 and 2014, we establish an unique cycle count scheme valid during the past 50 years, and derive an ephemeris with the orbital period 0.145025959(15) days. The O - C diagram of this linear ephemeris reveals systematic deviations which could have different causes. One of them could be a light-travel-time effect caused by the presence of a hypothetical third body near the star/brown dwarf mass limit, with an orbital period of the order of 70 years. We also examine the difficulty of the problematic of detecting sub-stellar or planetary companions of close red- dwarf white-dwarf binaries (including cataclysmic variables), and discuss other possible mechanisms responsible for the observed deviations in O - C. For RR Pic, we propose strategies in order to solve this question by new observations.
    [Show full text]
  • La Constellation Du Cocher Ou Auriga ( Latin )
    DansDans lala ss éérierie lesles constellationsconstellations lala constellationconstellation dudu CocherCocher ouou AurigaAuriga (( LatinLatin )) - Repérage - Caractéristiques - Histoire Constellation d’hiver, le Cocher fait partie des 48 constellations originellement répertoriées par Ptolémée dans son Almageste*. Superficie 657 deg² à comparer aux 1 255 deg² d’Hercule par exemple… * L'Almageste (qui est l'arabisation du grec ancien megistos (byblos) signifiant grand (livre)) est une œuvre de Claude Ptolémée datant du IIe siècle étant la somme des connaissances les plus avancées de son époque Patrice D écembre 2008 en mathématiques et en astronomie. L'Almageste contient également un catalogue d'étoiles. LocalisationLocalisation RepRep ééragerage • Le Cocher est une constellation très étendue traversée par la Voie Lactée et riche en amas d'étoiles, la constellation du Cocher se signale d'abord par son étoile principale, Capella. • Si la Grande Ourse est visible, Capella se situe dans la direction pointée par le grand chariot, à une vingtaine de degrés vers l’ Est. • Capella - Presque aussi brillante que Véga de la Lyre et d'une luminosité supérieure à celle de Rigel d'Orion. FormeForme • Partiellement circumpolaire, observée depuis une latitude de 45° Nord, la constellation dessine sensiblement un pentagone formé dans le sens des aiguilles d'une montre par Capella α Aur, ς Aur, ß du Taureau située juste à la limite sud de la constellation, puis en remontant vers le nord, θ Aur et ß Aur. • L'autre élément remarquable de la constellation est formé par les trois petites "chevrettes" η, ζ et ε Aur, qui forment un triangle serré au Sud de Capella. CaractCaract ééristiquesristiques CapellaCapella Capella (α Aurigae) appartient au groupe de tête des étoiles les plus éclatantes de nos nuits.
    [Show full text]
  • Metadata of the Chapter That Will Be Visualized Online
    Metadata of the chapter that will be visualized online Chapter Title Binary Systems and Their Nuclear Explosions Copyright Year 2018 Copyright Holder The Author(s) Author Family Name Isern Particle Given Name Jordi Suffix Organization Institute of Space Sciences (ICE, CSIC) Address Barcelona, Spain Organization Institut d’Estudis Espacials de Catalunya (IEEC) Address Barcelona, Spain Email [email protected] Corresponding Author Family Name Hernanz Particle Given Name Margarita Suffix Organization Institute of Space Sciences (ICE, CSIC) Address Barcelona, Spain Organization Institut d’Estudis Espacials de Catalunya (IEEC) Address Barcelona, Spain Email [email protected] Author Family Name José Particle Given Name Jordi Suffix Organization Universitat Politècnica de Catalunya (UPC) Address Barcelona, Spain Organization Institut d’Estudis Espacials de Catalunya (IEEC) Address Barcelona, Spain Email [email protected] Abstract The nuclear energy supply of a typical star like the Sun would be ∼ 1052 erg if all the hydrogen could be incinerated into iron peak elements. Chapter 5 1 Binary Systems and Their Nuclear 2 Explosions 3 Jordi Isern, Margarita Hernanz, and Jordi José 4 5.1 Accretion onto Compact Objects and Thermonuclear 5 Runaways 6 The nuclear energy supply of a typical star like the Sun would be ∼1052 erg if all 7 the hydrogen could be incinerated into iron peak elements. Since the gravitational 8 binding energy is ∼1049 erg, it is evident that the nuclear energy content is more 9 than enough to blow up the Sun. However, stars are stable thanks to the fact that their 10 matter obeys the equation of state of a classical ideal gas that acts as a thermostat: if 11 some energy is released as a consequence of a thermal fluctuation, the gas expands, 12 the temperature drops and the instability is quenched.
    [Show full text]
  • 1991Apj. . .370. . .78H the Astrophysical Journal
    The Astrophysical Journal, 370:78-101,1991 March 20 .78H . © 1991. The American Astronomical Society. All rights reserved. Printed in U.S.A. .370. SPATIALLY RESOLVED OPTICAL IMAGES OF HIGH-REDSHIFT QUASI-STELLAR OBJECTS 1991ApJ. Timothy M. Heckman,12,3 Matthew D. Lehnert,1,2,4 Wil van Breugel,3,5 and George K. Miley2,3,6 Received 1990 June 21 ; accepted 1990 August 29 ABSTRACT We present and discuss the results of a program of deep optical imaging of 19 high-redshift (z > 2) radio- loud QSOs. These data represent the first large body of nonradio detections of spatially resolved structure surrounding high-redshift QSOs. _1 In 15 of 18 cases, the Lya emission is spatially resolved, with a typical size of 100 kpc (for H0 = 75 km s 1 44 _1 Mpc“ ; q0 = 0). The luminosity of the resolved Lya is «10 ergs s («10% of the total Lya luminosity). The nebulae are usually asymmetric and/or elongated with a morphological axis that aligns with the radio source axis to better than « 30°. These properties are quite similar to those of the Lya nebulae associated with high-z radio galaxies. The brighter side of the nebula is generally on the same side as the brighter radio emis- sion and/or one-sided, jetlike radio structure. There is no strong correlation between the Lya isophotal and radio sizes (the Lya nebulae range from several times larger than the radio source to several times smaller). None of the properties of the nebulae correlate with the presence or strength of C iv “associated” absorption C^abs ^ ^em)* It is likely that the nebulae are the interstellar or circumgalactic medium of young or even protogalaxies being photoionized by QSO radiation that escapes anisotropically along the radio axis.
    [Show full text]
  • The Old Nova CP Puppis: a Carbon Nova and Asynchronous Polar?⋆
    A&A 539, A94 (2012) Astronomy DOI: 10.1051/0004-6361/201117251 & c ESO 2012 Astrophysics The old nova CP Puppis: a carbon nova and asynchronous polar? A. Bianchini1,T.Saygac2, M. Orio3, M. della Valle4, and R. Williams5 1 Department of Astronomy, University of Padova, vicolo dell’Osservatorio 3, 35122 Padova, Italy e-mail: [email protected] 2 Department of Astronomy and Space Sciences, Istanbul University, Istanbul 34119, Turkey 3 INAF – Osservatorio Astronomico di Padova, vicolo dell’Osservatorio 5, 35122 Padova, Italy 4 INAF – Osservatorio Astronomico di Napoli, Salita Moiariello 16, 80131 Napoli, Italy 5 Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA Received 12 May 2011 / Accepted 21 January 2012 ABSTRACT Context. CP Pup (Nova Pup 1942) showed outburst and quiescent characteristics indicating a very massive white dwarf, yet the standard spectroscopic dynamical analysis assuming an accretion disk yields an extremely low value for the white dwarf mass. However, some physical parameters and the accretion geometry are still poorly known. Aims. The nova was spectroscopically monitored between 1988 and 1996. We analyzed the whole data set in order to re-determine the spectroscopic period and examine its stability. We also looked for chemical anomalies in the spectrum. Methods. We obtained the radial velocity curves for the hydrogen and helium lines from our last better quality 1996 run. The mean 1996 spectrum yields information on the chemical composition of the binary. We also searched the mean period using the multi-year data set. Results. From the radial velocities of our complete data set we derive the most probable mean spectroscopic period and tentatively suggest revised ephemeris.
    [Show full text]