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

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

[1]  G. K. Skinner,et al.  Detectability of gamma-ray emission from classical novae with Swift/BAT , 2008, 0804.4791.

[2]  M. J. Page,et al.  Photometric calibration of the Swift ultraviolet/optical telescope , 2007, 0708.2259.

[3]  Ioannis Pachoulakis,et al.  Nova V351 puppis 1991: a multiwavelength study of the nebular phase , 1996 .

[4]  Margarita Hernanz,et al.  Gamma-rays from classical novae , 2008 .

[5]  Ronnie Killough,et al.  The Swift Ultra-Violet/Optical Telescope , 2001 .

[6]  Richard J. Rudy,et al.  The 1.0--1.3 Micron Spectrum of LkH alpha 101 , 1991 .

[7]  G. Sala,et al.  XMM-Newton Observations of Nova Sagittarii 1998 , 2007, 0704.3166.

[8]  D. R. van Rossum,et al.  Expanding atmosphere models for SSS spectra of novae , 2010, 1001.1462.

[9]  Kelly D. Denney,et al.  Strong Neon Emission in CSS081007:030559+054715: A Possible Oxygen/ Neon Nova , 2008 .

[10]  W. Pietsch,et al.  X‐ray emission from optical novae in M 31 , 2009, 0910.3865.

[11]  J. Greiner,et al.  X-ray off states and optical variability in CAL 83 , 2002 .

[12]  T Glanzman,et al.  Gamma-ray emission concurrent with the nova in the symbiotic binary V407 Cygni. , 2010, Science.

[13]  J. Walsh,et al.  Infrared and optical observations of Nova MUS 1983 , 1984 .

[14]  Joachim Krautter,et al.  The X-Ray Spectral Evolution of Classical Nova V1974 Cygni 1992: A Reanalysis of the ROSAT Data , 1998 .

[15]  A. P. Beardmore,et al.  Swift observations of CSS081007:030559+054715 , 2010 .

[16]  Ulisse Munari,et al.  Nova Sagittarii 2008 , 2008 .

[17]  Marina Orio,et al.  Chandra grating observation of Nova CSS 081007:030559+054715 , 2009 .

[18]  M. F. Bode,et al.  The outbursts of classical and recurrent novae , 2009, 0911.5254.

[19]  Chunhua Zhu,et al.  Gamma-ray sources like V407 Cygni in symbiotic stars , 2011 .

[20]  A. Ederoclite,et al.  Early spectral evolution of Nova Sagittarii 2004 (V5114 Sagittarii) , 2006 .

[21]  D. Schlegel,et al.  Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds , 1997, astro-ph/9710327.

[22]  D. Burrows,et al.  Determination of Confidence Limits for Experiments with Low Numbers of Counts , 1991 .

[23]  D. Schlegel,et al.  Maps of Dust Infrared Emission for Use in Estimation of Reddening and Cosmic Microwave Background Radiation Foregrounds , 1998 .

[24]  Akira Arai,et al.  Discovery of Multiple High-Velocity Narrow Circumstellar NaI D Lines in Nova V1280 Sco , 2010 .

[25]  U. Munari,et al.  Optical evolution of Nova Ophiuchi 2007 = V2615 Oph , 2008, 0803.2653.

[26]  H. Esenoglu,et al.  Spectral evolution of Nova (V1494) Aql and its high velocity jets , 2003 .

[27]  Joachim Krautter.  X‐ray Observations of Novae , 2002 .

[28]  George Sonneborn,et al.  V1974 cygni 1992: Optical and ultraviolet evolution and analysis , 1996 .

[29]  M. J. Darnley,et al.  X-ray detection of Nova V2468 Cygni and multiwavelength monitoring , 2009 .

[30]  Paula Szkody,et al.  The masses of V838 Herculis (Nova Herculis 1991) and OZ Aurigae , 1994 .

[31]  Arne A. Henden,et al.  The Outburst of the Very Fast Nova Aql 2009 (V1722 Aql) , 2010 .

[32]  M. F. Bode,et al.  AN INTERACTING WINDS MODEL FOR THE X-RAY-EMISSION FROM V838 HER (NOVA-HERCULIS 1991) , 1994 .

[33]  Scott J. Kenyon,et al.  An X-ray-emitting blast wave from the recurrent nova RS Ophiuchi , 2006, Nature.

[34]  Arne A. Henden,et al.  CATALOG OF 93 NOVA LIGHT CURVES: CLASSIFICATION AND PROPERTIES , 2010, 1004.3698.

[35]  M. F. Bode,et al.  EXQUISITE NOVA LIGHT CURVES FROM THE SOLAR MASS EJECTION IMAGER (SMEI) , 2010, 1009.1737.

[36]  Marina Orio.  X-RAY OBSERVATIONS OF CLASSICAL AND RECURRENT NOVAE IN OUTBURST , 2004 .

[37]  Olivier Chesneau,et al.  VLTI monitoring of the dust formation event of the Nova V1280 Scorpii , 2008, 0804.4129.

[38]  E. Leibowitz,et al.  V4633 Sgr – a probable second asynchronous polar classical nova , 2008, 0805.1444.

[39]  R. D. Campbell,et al.  THE DISTANCE AND MORPHOLOGY OF V723 CASSIOPEIAE (NOVA CASSIOPEIA 1995) , 2011, 1103.0624.

[40]  Barcelona,et al.  X‐ray observations of classical novae: Theoretical implications , 2009, 0910.4607.

[41]  Roberto Gilmozzi,et al.  HST Imagery of the Non-Expanding, Clumped "Shell" of the Recurrent Nova T Pyxidis , 1997 .

[42]  Shunsaku Okada,et al.  Suzaku Discovery of Hard X-Ray Pulsations from a Rotating Magnetized White Dwarf, AEAquarii , 2007, 0711.2716.

[43]  V. S. Dhillon,et al.  The mass of the white dwarf in the recurrent nova U Scorpii , 2001 .

[44]  Marina Orio,et al.  X-Ray Emission of Nova Puppis 1991: Accretion or a Shocked Shell? , 1996 .

[45]  M. Orio,et al.  X-ray emission from classical and recurrent-novae observed with ROSAT , 2001 .

[46]  J. Krautter,et al.  Swift Observations of the 2006 Outburst of the Recurrent Nova RS Ophiuchi. I. Early X-Ray Emission from the Shocked Ejecta and Red Giant Wind , 2006, astro-ph/0604618.

[47]  Alon Retter,et al.  V4745 Sgr – a nova above the period gap and an intermediate polar candidate , 2006 .

[48]  O. Yaron,et al.  An Extended Grid of Nova Models. II. The Parameter Space of Nova Outbursts , 2005 .

[49]  M. Della Valle,et al.  The Extraordinary X-ray Light Curve of the Classical Nova V1494 Aquilae (1999 No. 2) in Outburst: The Discovery of Pulsations and a “Burst” , 2002, astro-ph/0210072.

[50]  D. J. Stickland,et al.  Nova Cygni 1978 – I. The nebular phase , 1981 .

[51]  Mike Hapgood.  Numerical Modeling of Space Plasma Flows: ASTRONUM-2007 , 2009 .

[52]  Steven N. Shore.  Classical Novae: Optical and ultraviolet evolution , 2008 .

[53]  M. F. Bode,et al.  Silicate dust in the environment of RS Ophiuchi following the 2006 eruption , 2007 .

[54]  J.-U. Ness,et al.  V723 CASSIOPEIA STILL ON IN X-RAYS: A BRIGHT SUPER SOFT SOURCE 12 YEARS AFTER OUTBURST , 2008, 0801.3288.

[55]  S. Kimeswenger,et al.  The unusual Nova Cygni 2006 (V2362 Cygni) , 2008, 0801.2379.

[56]  R. Gehrz,et al.  Nucleosynthesis in Classical Novae and Its Contribution to the Interstellar Medium , 1998 .

[57]  Edouard Audit,et al.  Numerical Modeling of Space Plasma Flows: ASTRONUM-2008 , 2008 .

[58]  M. F. Bode,et al.  Double radio peak and non-thermal collimated ejecta in RS Ophiuchi following the 2006 outburst , 2009, 0902.2265.

[59]  B. Warner,et al.  High-speed photometry of faint cataclysmic variables – I. V359 Cen, XZ Eri, HY Lup, V351 Pup, V630 Sgr, YY Tel, CQ Vel and CE-315 , 2001, astro-ph/0107505.

[60]  M. F. Bode,et al.  X-ray detection of Nova Herculis 1991 five days after optical outburst , 1992, Nature.

[61]  Sumner Starrfield,et al.  Classical Novae: Thermonuclear processes , 2008 .

[62]  Rosa Poggiani.  Spectral evolution of nova V5558 Sgr (nova Sgr 2007): Pre-maximum and early decline stages , 2008 .

[63]  Bradley E. Schaefer,et al.  Discovery of a Second Nova Eruption of V2487 Ophiuchi , 2009, 0908.2143.

[64]  G. Sala,et al.  X-ray monitoring of optical novae in M 31 from July 2004 to February 2005 , 2007 .

[65]  Margarita Hernanz.  Classical nova explosions , 2002 .

[66]  Marina Orio,et al.  Chandra Observations of the Recurrent Nova IM Normae , 2005 .

[67]  A. P. Beardmore,et al.  Early X-ray detection of Nova Ophiuchi 2009 / V2672 Oph , 2009 .

[68]  K. Genovali,et al.  The Long-Term Spectroscopic Misadventures of AG Dra with a Nod Toward V407 Cyg: Degenerates Behaving Badly , 2012 .

[69]  J. Steiner,et al.  The Photometric Period of Nova MUSCAE 1983 , 1989 .

[70]  A. Dobrotka,et al.  Nova V5116 Sagittarii and searching for superhumps in nova remnants , 2007, 0710.5701.

[71]  J. S. Gallagher,et al.  Ultraviolet photometry from the Orbiting Astronomical Observatory. X - Nova FH Serpentis 1970 , 1974 .

[72]  Steven N. Shore,et al.  Multiwavelength analyses of the extraordinary nova LMC 1991 , 2001 .

[73]  Ramkrishna Das,et al.  Near-infrared studies of V1280 Sco (Nova Scorpii 2007) , 2008, 0809.4338.

[74]  Mario Livio,et al.  On the interpretation and implications of nova abundances: An abundance of riches or an overabundance of enrichments , 1994 .

[75]  Ulisse Munari,et al.  The extreme, possible symbiotic Mira V 407 Cyg and its relevance to the OH/IR sources , 1990 .

[76]  Izumi Hachisu,et al.  A PREDICTION FORMULA OF SUPERSOFT X-RAY PHASE OF CLASSICAL NOVAE , 2009, 0912.1136.

[77]  University of Sydney,et al.  Nova Sagittarii 1998 (V4633 Sgr): a permanent superhump system or an asynchronous polar? , 2001, astro-ph/0109149.

[78]  Richard C. Puetter,et al.  0.8-2.5 Micron Spectroscopy of Nova Ophiuchi 1998 , 2000 .

[79]  M. F. Bode,et al.  Models for the remnants of recurrent novae – III. Comparison with the X-ray observations of RS Ophiuchi (1985) , 1992 .

[80]  James A. Deyoung,et al.  The Photometric Period of V1974 Cygni (Nova Cygni 1992) , 1994 .

[81]  J. Dickey,et al.  H I in the Galaxy , 1990 .

[82]  Bradley E. Schaefer,et al.  NOVAE WITH LONG-LASTING SUPERSOFT EMISSION THAT DRIVE A HIGH ACCRETION RATE , 2010, 1002.1401.

[83]  Rosa Poggiani,et al.  The early spectroscopic evolution of nova V458 Vul (Nova Vulpeculae 2007) , 2008 .

[84]  Rosa Poggiani,et al.  The spectroscopic evolution of V2467 Cyg (Nova Cygni 2007) in the first months after the outburst , 2009 .

[85]  Robert D. Gehrz,et al.  The peculiar, fast Nova Herculis 1991 , 1992 .

[86]  G. C. Anupama,et al.  The 1999 Outburst of the Recurrent Nova U Scorpii , 2000 .

[87]  Marina Orio,et al.  Emergence of the Supersoft X-ray Phase of U Sco , 2010 .

[88]  L. Amati,et al.  The X-ray emission from Nova V382 Velorum - I. The hard component observed with BeppoSAX , 2001, astro-ph/0102437.

[89]  U. Munari,et al.  Properties, evolution and morpho-kinematical modelling of the very fast nova V2672 Oph (Nova Oph 2009), a clone of U Sco , 2010, 1009.0334.

[90]  M. M. Phillips,et al.  The Evolution and Classification of Postoutburst Novae Spectra , 1991 .

[91]  Christian Iliadis,et al.  Nucleosynthesis in classical novae , 2006 .

[92]  George Sonneborn,et al.  The early bolometric evolution of Nova Cygni 1992 , 1994 .

[93]  A. Retter,et al.  Photometric and spectroscopic study of nova Cassiopeiae 1995 (V723 Cas) , 2007 .

[94]  Sumner Starrfield,et al.  Theory and Observations of Classical Novae , 1978 .

[95]  Ofer Yaron,et al.  NON-EQUIPARTITION OF ENERGY, MASSES OF NOVA EJECTA, AND TYPE Ia SUPERNOVAE , 2010, 1002.2303.

[96]  Steven N. Shore,et al.  Abundance Analysis of the Extremely Fast ONeMg Novae V838 Herculis and V4160 Sagittarii , 2007 .

[97]  Baltimore,et al.  NON-LOCAL THERMAL EQUILIBRIUM MODEL ATMOSPHERES FOR THE HOTTEST WHITE DWARFS: SPECTRAL ANALYSIS OF THE COMPACT COMPONENT IN NOVA V4743 Sgr , 2010, 1006.2918.

[98]  J. P. Osborne,et al.  Swift X-ray observations of classical novae , 2007 .

[99]  Brian Warner,et al.  High-speed photometry of the recurrent nova IM Normae , 2003 .

[100]  Charles E. Woodward,et al.  Recent observational and theoretical studies of the classical nova outburst , 2011 .

[101]  Max-Planck-Institut fur Radioastronomie,et al.  THE EXPANDING NEBULAR REMNANT OF THE RECURRENT NOVA RS OPHIUCHI (2006). II. MODELING OF COMBINED HUBBLE SPACE TELESCOPE IMAGING AND GROUND-BASED SPECTROSCOPY , 2009, 0908.2704.

[102]  A. Shafter,et al.  On the Nova Rate in the Galaxy , 1997 .

[103]  B. Csak,et al.  Spectroscopic monitoring of the transition phase in nova V4745 Sgr , 2004, astro-ph/0408268.

[104]  J. M. C. Rawlings,et al.  Classical Novae: Dust and molecules in nova environments , 2008 .

[105]  Rolf Walder,et al.  3D simulations of RS Ophiuchi : from accretion to nova blast , 2008, 0804.2628.

[106]  B. Savage,et al.  A survey of interstellar H I from L-alpha absorption measurements. II , 1978 .

[107]  L. Pasquini,et al.  The evolution of Nova V382 Velorum 1999 , 2002, astro-ph/0205135.

[108]  Ulisse Munari,et al.  V459 Vulpeculae = Nova Vulpeculae 2007 No. 2 , 2007 .

[109]  B. Schaefer.  COMPREHENSIVE PHOTOMETRIC HISTORIES OF ALL KNOWN GALACTIC RECURRENT NOVAE , 2009, 0912.4426.

[110]  J. P. Osborne,et al.  THE SUPERSOFT X-RAY PHASE OF NOVA RS OPHIUCHI 2006 , 2010, 1011.5327.

[111]  R. E. Williams,et al.  THE SPECTRAL EVOLUTION AND EJECTA OF RECURRENT NOVA U Sco IN THE 2010 OUTBURST , 2010, 1009.4740.

[112]  Izumi Hachisu,et al.  A Universal Decline Law of Classical Novae. II. GK Persei 1901 and Novae in 2005 , 2007, astro-ph/0702563.

[113]  J. P. Osborne,et al.  An online repository of Swift/XRT light curves of Γ-ray bursts , 2007, 0704.0128.

[114]  Leonardo Vanzi,et al.  Infrared spectroscopy of the 1999 outburst of U Scorpii , 2001 .

[115]  Eric D. Ragan,et al.  V2491 Cyg - a possible recurrent nova ? , 2008 .

[116]  Richard J. Rudy,et al.  THE DUSTY NOVA V1065 CENTAURI (NOVA CEN 2007): A SPECTROSCOPIC ANALYSIS OF ABUNDANCES AND DUST PROPERTIES , 2010 .

[117]  Xiangcun Meng,et al.  WD+MS systems as the progenitor of SNe Ia , 2009, 0912.0804.

[118]  Alon Retter,et al.  Nova V4743 Sagittarii 2002: An Intermediate Polar Candidate , 2006, astro-ph/0604438.

[119]  M. A. Burlak.  Determining the interstellar extinction and distances for Galactic novae , 2008 .

[120]  S. Roca-F brega,et al.  Revista Mexicana de Astronomia y Astrofisica Conference Series , 2011 .

[121]  Jochen Greiner,et al.  V5116 Sagittarii, an Eclipsing Supersoft Postoutburst Nova? , 2008, 0801.3988.

[122]  Joachim Krautter,et al.  The nebular phase of Nova GQ Muscae 1983 - Evolution of the ionization of the optical spectrum , 1989 .

[123]  Steven N. Shore,et al.  Photo-ionization induced rapid grain growth in novae , 2004 .

[124]  Brian Warner.  Classical Novae: Properties of novae: an overview , 2008 .

[125]  Masahiro Tsujimoto,et al.  X-Ray Spectroscopy of the Classical Nova V458 Vulpeculae with Suzaku , 2008, 0810.3077.

[126]  Brian Warner,et al.  The eclipsing intermediate polar V597 Pup (Nova Puppis 2007) , 2009, 0905.0325.

[127]  P. Kahabka,et al.  Luminous Supersoft X-Ray Sources , 1997 .

[128]  Eric D. Ragan,et al.  Optical observations of KT Eri = Nova Eridani 2009 , 2009 .

[129]  Steven N. Shore,et al.  Nuclear Turnoff Times for ONeMg Novae Determined Using Ultraviolet Spectral Evolution , 2001 .

[130]  Enrico Camporeale,et al.  Numerical modeling of space plasma flows , 2009 .

[131]  Sumner Starrfield,et al.  ROSAT X-ray observations of nova V1974 Cygni: The rise and fall of the brightest supersoft X-ray source , 1996 .

[132]  J. J. Drake,et al.  THE EARLY BLAST WAVE OF THE 2010 EXPLOSION OF U SCORPII , 2010, 1007.2810.

[133]  Antonella Fruscione,et al.  Chandra’s first decade of discovery , 2010, Proceedings of the National Academy of Sciences.

[134]  Ulisse Munari,et al.  BVI photometry and the spectroscopy of Nova Scuti 2005 N.2 , 2006 .

[135]  Elena P. Pavlenko,et al.  Discovery of the optical variability of Nova V2491 Cyg , 2008 .

[136]  F. A. Ringwald,et al.  Early post-maximum spectral evolution of the fast novae V4742 Sagittarii and V4743 Sagittarii , 2003 .

[137]  J. P. Osborne,et al.  XMM-NEWTON X-RAY AND ULTRAVIOLET OBSERVATIONS OF THE FAST NOVA V2491 Cyg DURING THE SUPERSOFT SOURCE PHASE , 2011, 1103.4543.

[138]  Raquel Yumi Shida,et al.  Light Curves for Recent Magellanic Cloud Novae , 2004 .

[139]  Rosa Poggiani.  The spectroscopic evolution of V459 Vul (Nova Vul 2007 #2) , 2010 .

[140]  James MacDonald,et al.  The decline and fall of classical novae , 1985 .

[141]  Alon Retter,et al.  The Orbital Period of Nova V2540 Ophiuchi (2002) , 2005, Publications of the Astronomical Society of Australia.

[142]  M. F. Bode,et al.  Swift observations of the 2006 outburst of the recurrent nova rs ophiuchi. II. One-dimensional hydrodynamical models of wind-driven shocks , 2007 .

[143]  Mario Livio,et al.  The Calibration of Novae as Distance Indicators , 1995 .

[144]  J. Greiner,et al.  XMM-Newton observations of Nova LMC 2000 , 2003 .

[145]  Massimo Capaccioli,et al.  Properties of the Nova Population in M31 , 1989 .

[146]  Arne A. Henden,et al.  Absolute spectrophotometry and photometric evolution of Nova Scuti 2005 N.1 (≡ V476 Sct) , 2006 .

[147]  M. F. Bode,et al.  X-Ray Spectroscopic Diagnosis of a Wind-Collimated Blast Wave and Metal-Rich Ejecta from the 2006 Explosion of RS Ophiuchi , 2009 .

[148]  Matthew W. Muterspaugh,et al.  Interferometric Observations of V1663 Aquilae (Nova Aql 2005) , 2007 .

[149]  M. F. Bode,et al.  Early Infrared Spectral Development of V1187 Scorpii (Nova Scorpii 2004 No. 2) , 2004 .

[150]  Toshikazu Shigeyama,et al.  COMPTON DEGRADATION OF GAMMA-RAY LINE EMISSION FROM RADIOACTIVE ISOTOPES IN THE CLASSICAL NOVA V2491 CYGNI , 2010, 1007.4386.

[151]  J. Krautter,et al.  A Chandra Low Energy Transmission Grating Spectrometer Observation of V4743 Sagittarii: A Supersoft X-Ray Source and a Violently Variable Light Curve , 2003 .

[152]  George Sonneborn,et al.  Optical and ultraviolet spectrophotometry of the ONeMg Nova V838 Herculis 1991 , 1996 .

[153]  Marina Orio,et al.  X-Ray Spectroscopy of the 2006 Outburst of RS Ophiuchi , 2007, 0709.4512.

[154]  Margarita Hernanz,et al.  Gamma-rays from classical nova explosions: theory and observations , 2005 .

[155]  Alon Retter,et al.  The Detection of a 3.5 hr Period in the Classical Nova Velorum 1999 (V382 Vel) and the Long-Term Behavior of the Nova Light Curve , 2006, astro-ph/0601713.

[156]  Steven N. Shore,et al.  The Ultraviolet and X-ray View of the Demise of Nova V1974 Cygni , 1996 .