SIMBAD references

2016ApJ...821...14M - Astrophys. J., 821, 14-14 (2016/April-2)

Constraining the angular momentum evolution of V455 Andromedae.

MUKADAM A.S., PYRZAS S., TOWNSLEY D.M., GANSICKE B.T., HERMES J.J., SZKODY P., KEMP J., PATTERSON J., DING C., WOLF K., GEMMA M., KARAMEHMETOGLU E. and ROCK J.

Abstract (from CDS):

Time-series photometry on the cataclysmic variable V455 Andromedae (hereafter V455 And, HS 2331+3905) reveals a rotation period shorter than the orbital period, implying the presence of a magnetic field. We expect that this magnetic field channels the accreted matter from the disk toward the white dwarf poles, classifying it as an Intermediate Polar. The two polar spinning emission areas are visible in the lightcurves at the rotation period of 67.61970396 ± 0.00000072 s, and its harmonic. Using photometric observations of V455 And obtained from 2007 October to 2015, we derive 3σ upper limits to the rate of change of the spin harmonic (SH) with time to be dPSH/dt <= -7.5 x 10-15 s s-1 employing the O-C method, and -5.4 x 10-15 s s-1 with a direct nonlinear least squares fit. There is no significant detection of a changing spin period for the duration of 2007 October-2015. The 3σ upper limit for the rate of change of spin period with time is dPspin/dt <= -10.8 x 10-15 s s-1 or -0.34 µs yr-1. V455 And underwent a large-amplitude dwarf nova outburst in 2007 September. The pre-outburst data reflect a period 4.8 ± 2.2 µs longer than the best-fit post-outburst spin period. The angular momentum gained by the white dwarf from matter accreted during outburst and its slight subsequent shrinking should both cause the star to spin slightly faster after the outburst. We estimate that the change in spin period due to the outburst should be 5 µs, consistent with the empirical determination of 4.8 ± 2.2 µs (3σ upper limit of 11.4 µs).

Abstract Copyright: © 2016. The American Astronomical Society. All rights reserved.

Journal keyword(s): novae, cataclysmic variables - stars: dwarf novae - stars: individual: (V455 And, HS 2331+3905) - stars: variables: general - white dwarfs

Simbad objects: 9

goto Full paper

goto View the references in ADS

To bookmark this query, right click on this link: simbad:2016ApJ...821...14M and select 'bookmark this link' or equivalent in the popup menu