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What are Significant or Noteworthy Outbursts (SNOBs)

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SXN's picture
Joined: 2010-03-12

Observers monitoring CVs for outbursts should have some knowledge of what is an important, rare or interesting outburst, and which are more common or mundane. With the current outburst of UZ Boo, it seems a good time to revisit what is a significant or noteworthy outburst and how and where it should be reported. 

In general, the rarer the occurence of outbursts, the more interesting they are. So stars that only have events a few times in a lifetime, or once every ten or more years are of great interest. These would include recurrent novae (NR) and WZ Sge type dwarf novae (UGWZ). You can search VSX and come up with a list of these types of stars that are visible from your location, or you can download the lists attached to this post and customize them for your use.

If you detect an outburst of any of these stars you should report it immediately to the AAVSO via this forum and/or the Cataclysmic Variable Forum. I would appreciate it if you also reported it to CVnet via the cvnet-outburst list. This list is monitored 24/7 and your announcement will be sure to get to the right people immediately. Other groups who will be keenly interested in announcments of this type are the BAAVSS-alert list, Center for Backyard Astrophysics (CBA) and VSNET-alert.

There is another well maintained list of interesting recurrent outbursting objects maintained by Gary Poyner and the BAAVSS, The Recurrent Objects Programme. This list includes some other interesting members of the CV zoo, like old novae, x-ray novae, little known nova-like CVs, and some unusual SU UMa type (UGSU) systems.

It is very important that you be accurate when reporting a rare outburst of this type. I see false detections of UZ Boo about every other week, so I usually ignore them. Until there is confirmation, I am skeptical. 9 times out of 10 the sky isn't falling, don't be "Chicken Little".

We used to have a list in My News Flash you could subscribe to called SNOBs (Significant or Noteworthy Outbursts). It was a list of the rare and noteworthy objects you could monitor via MNF, but it was dropped during the last revision of the application. If you want to keep an eye on this type of activity I have created a few comma delimited text files you can drop into MNF to create your own version of the SNOBs list and add them to your profile. These are also attached to this post.

(MNF NR 17 objects, MNF UGWZ 64 objects, MNF ROP List 79 objects) 

There you have it. A few lists of CVs worth waiting for, that you can get excited about if you are the one persistent and lucky enough to catch one of these rare birds. Happy Hunting!

NR by RA 2013.csv1.26 KB
UGWZ by RA.csv5.11 KB
MNF NR 20130725.txt161 bytes
MNF UGWZ List 20130725.txt1016 bytes
MNF ROP List.txt898 bytes
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