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ES Dra appears to be coming out of a long standstill

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roe's picture
ES Dra appears to be coming out of a long standstill

See LC for past 200 days with results from last night

SXN's picture
ES Dra appears to be coming out of a long standstill

You may be right, Jim. It might be too early to call it that, but we'll see.

Since 2010 ES Dra has spent almost as much time in standstill (around 15.2) as it has in the dwarf nova outburst cycle. Coverage has been very good.

There is dense enough coverage to show that it didn't drop to quiescence before going into outburst either, if this indeed turns out to be an outburst. We've never seen that before in ES Dra, so this would be an interesting find. 9 of the 22 known Z Cams exhibit this behavior, so it turned out to be not so uncommon. Your data might add another one to the list.

ES DRA 2014 Mar. 05.91542 15.081 0.074 V BPO
ES DRA 2014 Mar. 05.13678 14.662 0.1 V ROE
ES DRA 2014 Mar. 01.88890 15.2 Vis. DPV
ES DRA 2014 Feb. 28.15638 15.14 0.03 V ROE
ES DRA 2014 Feb. 27.15500 15.149 0.032 V ROE
ES DRA 2014 Feb. 26.41808 15.357 0.024 V BJAA

ES Dra was only recently classified as  UGZ in  The orbital period and variability of the dwarf nova ES Draconis, Ringwald F.A. and Velasco K., 2012NewA...17..108R 

The classification was based on AAVSO data, as stated in the abstract - " The long-term light curve of ES Dra compiled by the American Association of Variable Star Observers (AAVSO) shows that ES Dra is a Z Cam star, which between 1995 and 2009 spent most of its time in standstill."

So if you ever wonder are astronomers and citizen scientists actually using your data in their research, the answer is an emphatic yes. Keep up the good work!

roe's picture
ES Dra

[quote=roe]See LC for past 200 days with results from last night[/quote]

Since reporting this "mini-outbreak" I had one other similar observation but I noticed in the LCG that other observers did not get the same results.  I checked my images and can find nothing wrong with them (so please don't start emailing me!).  I certainly check to see why my data may look different than others, but I never change my data based on other's results unless I am really dubious of my image.  Not the case here, so the poor researcher will have to make the call.

BTW, my last two results are back down into the (recent) "normal" range (ie, still in standstill).

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