AAVSO Alert Notice 659

KQ Monocerotis being observed with the Chandra X-ray Observatory (CXO)

25 January 2019: Further to AAVSO Alert Notice 652, Dr. Koji Mukai (NASA Goddard Space Flight Center) informs us that KQ Mon, one of the novalike variables in his target list, will be observed with Chandra on 2019 January 29 20:18 UT – January 30 00:28 UT.

Knowing the status of the target is essential for interpreting the X-ray data. Dr. Mukai thanks observers for the observations they have already made of KQ Mon, and asks if more observations (a snapshot every one to two nights) could be made between now and February 9. V filter is optimal. Visual observations are welcome. The visual range of KQ Mon is 12.5–13.7.

As Dr. Mukai wrote in Alert Notice 652, "We think we know how dwarf novae behave in X-rays, through various campaigns (famously that one on SS Cyg in outburst that Janet Mattei [and AAVSO observers] was heavily involved in, with Pete Wheatley and Chris Mauche, 2003MNRAS.345...49W): they are X-ray bright in optical quiescence, and fainter and softer in X-rays during outburst. In the optical, we think of nova-likes as systems in permanent outburst – but in X-rays, they don’t quite resemble dwarf novae in outburst. In fact, we haven’t seen a clear pattern, when we made X-ray observations of nova-like systems at various optical magnitudes. This Chandra program is part of an effort to look for patterns and to understand their X-ray emission."

Observers are reminded that occasional snapshots (again, V is preferred) are also needed of the remaining targets on the list given in Alert Notice 652 (1SWASP J022916.91-395901.4, LQ Peg, UU Aqr; V378 Peg and EC 21178-5417 have already been observed). Please see that Alert Notice for information on coordinates and magnitude ranges.

Coordinates (2000) of KQ Mon:  RA 07 31 21.13   Dec. -10 21 49.4

Charts with comparison star sequences for KQ Mon may be created using the AAVSO Variable Star Plotter (VSP).

Please submit observations to the AAVSO International Database using the name KQ Mon.

AAVSO Forums: This campaign is the topic of the AAVSO Campaigns and Observation Reports forum thread https://www.aavso.org/six-novalikes-2018-campaign and the Cataclysmic Variables forum thread https://www.aavso.org/six-novalikes-2018-campaign-01

This AAVSO Alert Notice was compiled by Elizabeth O. Waagen.

The Z CamPaign