dwarf nova

Special Notice #423: RX And observations needed urgently now

October 11, 2016: Further to AAVSO Alert Notice 549, observations of the dwarf nova RX And are urgently requested immediately. The system *may* be going into outburst, and confirmation is essential in order to know whether to trigger ToO observations with Chandra and other instrumentation.

Alert Notice 549: RX And Chandra observing campaign

September 1, 2016: Dr. Christian Knigge (University of Southampton) and colleagues have requested AAVSO coverage of the Z Cam dwarf nova RX And in support of Chandra X-ray observations to be carried out via a Target of Opportunity (TOO) triggering when the system is in a suitable outburst.

Special Notice #418: RX And monitoring needed for VLA observations

July 5, 2016: Further to AAVSO Alert Notice 539, Deanne Coppejans and colleagues request optical monitoring of the Z Cam dwarf nova RX And in support of their campaign to observe it with the Very Large Array (VLA) in their ongoing radio jet research.

Deanne writes in a post to the AAVSO Forum thread on this campaign: "We are going to try and catch RX And in quiescence again in the next three weeks. The optical coverage of it is still sparse, so any observations you take of it will be extremely useful."

Alert Notice 180: 2337+56 Nova Cassiopeiae 1993 [V705 Cas] AND Special request to monitor dwarf novae

February 8, 1994

2337+56 NOVA CASSIOPEIAE 1993  [V705 Cas]

This bright nova, discovered on December 7.47 UT by Syuichi Nakano of Japan at photographic magnitude 6.5 (see AAVSO Notice 179), has been very well monitored by observers worldwide. Its optical light curve, created from observations reported to the AAVSO, indicates it brightened to about visual magnitude 5.7 by mid·Oecember, and then has slowly declined to magnitude 8.4 by February 7, with fluctuations as much as 1 magnitude in amplitude.

Alert Notice 539: Dwarf novae observations requested for VLA campaign

March 1, 2016: Ms. Deanne Coppejans (PhD candidate, Radboud University Nijmegen (Netherlands) and University of Cape Town) and colleagues have requested AAVSO observer assistance in monitoring several northern dwarf novae in support of their campaign to observe them with the Very Large Array (VLA) in their ongoing radio jet research. Their research on radio jets in dwarf novae has been discussed in AAVSO Alert Notice 505.

Special Notice #413: SU UMa observations needed now

February 23, 2016: Deanne Coppejans (Department of Astrophysics, Radboud University Nijmegen) requests observations of the dwarf nova SU UMa now in order to determine its status. She and colleagues observed it on 20 February 2016 with the Very Large Array (VLA) and need to know whether it is (was) in outburst.

Observations of SU UMa in the AAVSO International Database from around the time of the VLA observations show it to be in quiescence:

Alert Notice 505: Monitoring of Northern dwarf novae for radio jets campaign

October 24, 2014: Ms. Deanne Coppejans (PhD candidate, Radboud University Nijmegen (Netherlands) and University of Cape Town) and colleagues have requested AAVSO observer assistance in monitoring several dwarf novae in support of their campaign to observe them in outburst with the Very Large Array (VLA) to search for radio jets.

Special Notice #388: Outburst of VSX J213806.5+261957

October 23, 2014: Carey Chiselbrook (Georgia, United States; AAVSO observer code CCY) observed the WZ Sge-type dwarf nova VSX J213806.5+261957 in outburst at a visual magnitude of 9.7 on 2014 October 22.0590 (JD 2456952.55903). Prior to the outburst detection,  the last observation (also by CCY) indicated the star was not in outburst less than 24 hours prior (mvis < 13.8 at JD 2456951.6326).

Special Notice #15: V1316 Cyg Monitoring Campaign

July 14, 2006: Gary Poyner, Jeremy Shears and David Boyd (all BAA-VSS) have requested help in monitoring the dwarf novae V1316 Cyg for outbursts in the current observing season.

Typically, V1316 Cyg experiences many brief outbursts that can last from less than a day to 3 days with an amplitude of less than 2 magnitudes. Poyner et al. have recently authored a paper describing this behaviour for the Journal of the BAA. It is available online in preprint form at this URL:

http://arxiv.org/abs/astro-ph/0605284