The X-ray spectral evolution of classical Nova V1974 Cygni 1992: A reanalysis of the ROSAT data

Download

index.pdf

Date

1998-05-20

Author

Balman, Şölen
Krautter, J
Ogelman, H

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

187
views

0
downloads

We present a spectral analysis of the archival X-ray data of classical Nova V1974 Cygni 1992 (Nova Cygni 1992) obtained by the ROSAT Position Sensitive Proportional Counter (PSPC). The X-ray spectrum is fitted with a two-component model. The first component is a white dwarf atmosphere emission model developed for the remnants of classical novae near the Eddington luminosity. The model is used to fit the soft X-ray data in the similar to 0.1-1.0 keV range, where the bulk of emission is below 0.7 keV. The second component is a Raymond-Smith model of thermal plasma applied to the hard X-ray emission above similar to 1.0 keV. The postoutburst X-ray spectrum of the remnant white dwarf is examined in the context of evolution on the Hertzsprung-Russell diagram using an O-Ne- and a C-O-enhanced atmosphere emission model. A constant bolometric luminosity evolution is detected with increasing effective temperature and decreasing photospheric radius using the O-Ne-enhanced model. The unabsorbed soft X-ray flux for the constant bolometric luminosity phase is found to be in the range (1.7-2.2) x 10(-7) ergs s(-1) cm(-2). A peak effective temperature of 51 eV (5.9 x 10(5) K) is detected 511 days after outburst. We also present the spectral development of the hard X-ray component. It is found to evolve independently of the soft one. The maximum of the hard X-ray emission is reached at similar to 150 days after outburst with an unabsorbed flux of similar to 2.0 x 10(-11) ergs s(-1) cm(-2) corresponding to a luminosity of (0.8-2.0)x 10(34) ergs s(-1) at a 2-3 kpc source distance. The time evolution of the hard X-ray flux and the plasma temperatures decreasing from 10 keV to 1 keV suggest emission from shock-heated gas as the origin of the hard X-ray component.

Subject Keywords

Space and Planetary Science, Astronomy and Astrophysics

URI

https://hdl.handle.net/11511/57126

Journal

ASTROPHYSICAL JOURNAL

DOI

https://doi.org/10.1086/305600

Collections

Department of Physics, Article

Suggestions

OpenMETU
Core

The first resolved and detected classical nova shell in X-rays: The shell of Nova Persei 1901 Balman, Şölen; Ogelman, HB (IOP Publishing, 1999-06-20) We present the ROSAT High-Resolution Imager data of the first resolved and detected classical nova shell in the X-ray wavelengths: the shell of Nova Persei 1901. We find that the X-ray nebula is composed of knots/clumps and has an elliptical shape with a total count rate of about 0.01 +/- 0.001 counts s(-1). We estimate that the spectrum is of thermal origin with a luminosity of similar to 8.0 x 10(31) ergs s(-1) and an X-ray temperature of similar to 2.0 x 10(6) K in the 0.1-2.4 keV energy range. The knots...
Discovery of irradiation-induced variations in the light curve of the classical nova V2275 Cyg (N Cyg 2001 No. 2) Balman, Şölen; Yilmaz, A; Retter, A; Saygac, T; Esenoglu, H (Oxford University Press (OUP), 2005-01-11) We present charge-coupled device (CCD) photometry, light curve and time-series analysis of the classical nova V2275 Cyg (N Cyg 2001 No. 2). The source was observed for 14 nights in total in 2002 and 2003 using an R filter with the 1.5-m Russian-Turkish joint telescope (RTT150) at the TUBITAK National Observatory in Antalya, Turkey, as part of a large programme on the CCD photometry of cataclysmic variables. We report the detection of two distinct periodicities in the light curve of the nova: (a) P-1 = 0.314...
The XMM-Newton detection of extended emission from the nova remnant of T Pyxidis Balman, Şölen (Oxford University Press (OUP), 2010-05-01) We report the detection of an extended X-ray nebulosity with an elongation from north-east to south-west in excess of 15 arcsec in a radial profile and imaging of the recurrent nova T Pyx using the archival data obtained with the X-ray Multi-Mirror Mission (XMM-Newton), European Photon Imaging Camera (pn instrument). The signal-to-noise ratio in the extended emission (above the point source and the background) is 5.2 over the 0.3-9.0 keV energy range and 4.9 over the 0.3-1.5 keV energy range. We calculate a...
XMM-NEWTON OBSERVATIONS OF LUMINOUS SOURCES IN NEARBY GALAXIES NGC 4395, NGC 4736, AND NGC 4258 AKYÜZ, AYSUN; Kayaci, S.; Avdan, H.; Ozel, M. E.; SONBAŞ, EDA; Balman, Şölen (IOP Publishing, 2013-03-01) We present the results of a study of non-nuclear discrete sources in a sample of three nearby spiral galaxies (NGC 4395, NGC 4736, and NGC 4258) based on XMM-Newton archival data supplemented with Chandra data for spectral and timing analyses. A total of 75 X-ray sources have been detected within the D-25 regions of the target galaxies. The large collecting area of XMM-Newton makes the statistics sufficient to obtain spectral fitting for 16 (about 20%) of these sources. Compiling the extensive archival expo...
A Study on W Ursae Majoris-Type Systems Recognised by the ROTSE-IIId Experiment Coker, D.; ÖZDEMİR, SACİT; YEŞİLYAPRAK, Cahit; Yerli, Sinan Kaan; AKSAKER, NAZIM; Gucsav, B. B. (Cambridge University Press (CUP), 2013-01-24) We present a study on characterising the light curves of W UMa-type systems gathered from the archive containing 5 years of data observed with the Robotic Optical Transient Search Experiment Telescope (ROTSE-IIId) located in Turkey. A sample of 45 W UMa-type systems was studied on the basis of Fourier decomposition of light curves and some basic geometrical parameters, namely degree of contact (f), mass ratio (q), and orbital inclination (i), as approximated values for these systems were determined. Moreove...

Citation Formats

Ş. Balman, J. Krautter, and H. Ogelman, “The X-ray spectral evolution of classical Nova V1974 Cygni 1992: A reanalysis of the ROSAT data,” ASTROPHYSICAL JOURNAL, pp. 395–406, 1998, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/57126.