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Special Notice #175: Request for observations of high-mass X-ray binaries

AAVSO Special Notice #175

Request for observations of high-mass X-ray binaries
November 8, 2009

Dr. Gordon Sarty, University of Saskatchewan, Canada, requests our continuing assistance in his ongoing radial velocity observations of High Mass X-ray Binaries (HMXBs).  See AAVSO Alert Notice 377, and Special Notice 163 for prior requests and project information.  Dr. Sarty provides the following text for the current request:

"Please obtain BVRI photometry (or any subset thereof, VI preferred) of the following six HMXBs for the time period of our radial velocity observations from November 9 to December 10. The actual scheduled observing times are November 9-11, November 23-30, December 7-10 if you want to get observations that are simultaneous with ours. All observations of the HMXBs at any time are valuable. The targets for this observing campaign are:

Desig.   Name         R.A.(2000) Dec.(2000)  Mag  LPH no.  AUID
2157+49  V2175 Cyg   22:01:38.2  +50:10:04.6  8.8  127    000-BFS-469
2204+54  2206+543    22:07:57.1  +54:31:05.8  9.9  128    000-BDC-531 [V1008 Cep]
0140+60B V831 Cas    01:47:00.2  +61:21:23.7  11.3 029    000-BCY-758
0434+41  RXJ0440.9+  04:40:59.3  +44:31:49.3  10.8 034    000-BCZ-082 [LS V +44 17]
0515+37  V420 Aur    05:22:35.2  +37:40:33.6  7.5  040    000-BCT-897
0630+05B SAXJ0635+0  06:35:18.3  +05:33:06.3  12.8 058    000-BCZ-435 [SAX J0635+0533]

[Note: when generating charts or looking up these objects with VSX, please use the coordinates or the AUID.  The entry for RJX0440.9+ is currently unavailable in VSX pending review, but data can still be submitted for this object.]

Our radial velocity measurements will be done with the Dominion Astrophysical Observatory (DAO) 1.85-m Plaskett telescope, in Victoria, B.C., Canada. We will alternate observations of a different subset of the six stars throughout each night. The observer will be Dave Balam, who can be reached by e-mail to Interested AAVSO observers should concentrate on one star per night, all night, for as many nights as you can devote, while we are observing.

For more background information on the HMXB project, please see our JAAVSO preprint at

Charts with project specific information may be downloaded at:

Please submit your observations directly to the AAVSO International Database.

Thanks for your ongoing coverage of the HMXBs.

Please direct any questions about this observing campaign to Dr. Gordon Sarty at ."

Information on submitting observations to the AAVSO may be found at:


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