American Association of Variable Star Observers (AAVSO)
Thu, 09/01/2016 - 23:09

AAVSO Alert Notice 549 announces a new campaign on RX And by Dr. Christian Knigge and colleagues. Please see the notice for information and instructions. Many thanks!

Good observing,

Elizabeth Waagen, AAVSO HQ


RX And measurement

I submitted my first 3 observations of RX And; I'm measuring around mag 11.8, and it might be continuing to increase.


I'm continuing to monitor it tonight.

-Joe Ulowetz

RX And,2457673.5916550928,11.840,0.002,CV,NO,STD,000-BBC-329,11.698,000-BBC-346,12.066,1.250,NA,X16738LU ,na
RX And,2457673.5925115743,11.839,0.002,CV,NO,STD,000-BBC-329,11.752,000-BBC-346,12.120,1.247,NA,X16738LU ,na
RX And,2457673.5933796298,11.819,0.002,CV,NO,STD,000-BBC-329,11.811,000-BBC-346,12.174,1.243,NA,X16738LU ,na

American Association of Variable Star Observers (AAVSO)
Update on the RX And Chandra observation and AAVSO campaign

Hi everybody,

I'm the PI of the Chandra program on RX And that was behind the AAVSO campaign on this object. I just wanted to give you all a brief update on what has been happening.

First off, thanks so much to everybody who contributed! Your help was essential both for triggering in a timely fashion -- which we did! -- and in carefully tracking the outburst during which our Chandra observation took place. These things have been crucial for us in achieving our science goals.

We're still looking at the X-ray data we obtained, so what follows is all a bit preliminary. However, briefly, it looks like there was no strong soft X-ray or extreme ultraviolet flux detected during the observation. Establishing whether or not this was there was the main goal for this obervation, and a crucial factor was to make sure that we knew where in the outburst we caught the system.

As you may know, the purpose of this Chandra observations was primarily to act as a pathfinder for a much larger multi-wavelength program we are planning, which will hopefully observe an entire dwarf nova eruption across a huge range of wavelengths (X-ray to radio) and with high-ish cadence photometry and spectroscopy. This hasn't ever been done before, and the point of this pathfinder observation was to check if RX And is a good target for this. The fact that it doesn't have detectable soft X-ray flux -- which we suspect is simply due to extinction along the line of sight to the system -- probably means that it isn't.

Establishing this is a good thing -- there are other targets we can try, and the last thing we want to do is waste a huge campaign on a sub-optimal target. In fact, we have another Chandra pathfinder observation approved to check out YZ Cnc, which is another interesting candidate system. I very much hope the AAVSO will help us again in monitoring that system -- this campaign is likely to take place early next year.

Thanks again for all your help with this. If the data we obtained turns out to be sufficiently interesting to publish in its own right, everybody who contributed data to the campaign will obviously be invited as a co-author.



Professor Christian Knigge
Physics & Astronomy
University of Southampton
Southampton SO17 1BJ