2002AJ....123..413S


Query : 2002AJ....123..413S

2002AJ....123..413S - Astron. J., 123, 413-419 (2002/January-0)

X-Ray/Optical studies of two outbursts of the intermediate polar YY (DO) Draconis.

SZKODY P., NISHIKIDA K., ERB D., MUKAI K., HELLIER C., UEMURA M., KATO T., PAVLENKO E., KATYSHEVA N., SHUGAROV S. and COOK L.

Abstract (from CDS):

YY Draconis (likely the same variable called DO Draconis) is one of a small number of intermediate polars (IPs) that show outburst behavior. We report results from Target of Opportunity observations with the Rossi X-Ray Timing Explorer, together with ground-based optical photometry during outbursts in 1999 September and 2000 November. Similar behavior was evident in both outbursts. At outburst, the X-ray flux increased by more than a factor of 12, and the spectrum became hotter and more absorbed compared to quiescence. While the spin pulse at 529 s is clearly present in the X-ray data at 2-4 days past outburst peak and during quiescence, it was not detected in the X-ray data closest to outburst (1.5 days). This is contrary to the large increase in spin pulse amplitude that has been seen during outbursts of the IPs GK Per, XY Ari, and EX Hya. The differences in YY Dra are likely due to its unique geometry, with two relatively equal poles located near the white dwarf equator. The equal enhancement of both poles near outburst could account for the low pulse amplitude, while unequal feeding of the poles as the magnetosphere recedes during decline could explain the changes in amplitude and pulse shape. The changing height of the shocks may also have an effect on the visibility of both poles.

Abstract Copyright:

Journal keyword(s): Stars: Novae, Cataclysmic Variables - Stars: Individual: Constellation Name: YY Draconis - stars: individual (DO Draconis) - X-Rays

Simbad objects: 7

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Number of rows : 7
N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2023
#notes
1 V* XY Ari CV* 02 56 08.185 +19 26 34.12           ~ 151 1
2 V* GK Per No* 03 31 12.0098863320 +43 54 15.469951212   14.139 13.090 12.589   K1IV 913 0
3 V* TV Col CV* 05 29 25.5292422792 -32 49 03.900212364   14.219 13.846 14.181   K2V 326 0
4 V* YY Dra EB* 11 43 35 +71 42.2           ~ 35 1
5 V* DO Dra CV* 11 43 38.4921265896 +71 41 20.559036192       13.747   DQ 215 1
6 V* EX Hya CV* 12 52 24.2222471899 -29 14 55.999766523   13.51 13.49 13.55   M5-6V 684 0
7 V* V1223 Sgr CV* 18 55 02.3108012664 -31 09 49.584656268           ~ 328 0

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2023.03.26-00:52:40

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