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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.
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    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.
  • The Old Nova CP Puppis: a Carbon Nova and Asynchronous Polar?⋆

    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.