Chandra Observation of V426 Oph: Weighing the Evidence for a Magnetic White Dwarf

Details Chandra Observation of V426 Oph: Weighing the Evidence for a Magnetic White Dwarf Chandra Observation of V426 Oph: Weighing the Evidence for a Magnetic White Dwarf

2004-04-14

arxiv.org/abs/astro-ph/0404289v1

Astrophys.J. 610 (2004) 991-1000

Astronomy and Astrophysics

Astrophysics

11 pages, 7 figures, 5 tables. Accepted for publication in the Astrophysical Journal (to appear August 2004)

Scientific paper

10.1086/421864

We report the results of a 45 ks Chandra observation of the cataclysmic variable V426 Ophiuchus. The high resolution spectrum from the high-energy transmission grating spectrometer is most consistent with a cooling flow model, placing V426 Oph among the group of CVs including U Gem and EX Hya. An uninterrupted lightcurve was also constructed, in which we detect a significant 4.2 hr modulation together with its first harmonic at 2.1 hrs. Reanalysis of archival Ginga, and ROSAT X-ray lightcurves also reveals modulations at periods consistent with 4.2 and/or 2.1 hrs. Furthermore, optical photometry in V, simultaneous with the Chandra observation, indicates a modulation anti-correlated with the X-ray, and later more extensive R band photometry finds a signal at ~2.1 hrs. The earlier reported X-ray periods at ~0.5 and 1 hrs appear to be only transient and quasi-periodic in nature. In contrast, the 4.2 hr period or its harmonic are stable and persistent in X-ray/optical data from 1988 to 2003. This periodicity is clearly distinct from the 6.85 hr orbit, and could be due to the spin of the white dwarf. If this is the case, V426 Oph would be the first long period intermediate polar with a ratio P_spin/P_orb of 0.6. However, this interpretation requires unreasonable values of magnetic field strength and mass accretion rate.

Affiliated with

Also associated with

No associations

Rating

Chandra Observation of V426 Oph: Weighing the Evidence for a Magnetic White Dwarf does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Chandra Observation of V426 Oph: Weighing the Evidence for a Magnetic White Dwarf, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Chandra Observation of V426 Oph: Weighing the Evidence for a Magnetic White Dwarf will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-556244