Alert Notice 543: 20 Cataclysmic variables to be observed by William Herschel Telescope

May 24, 2016: Roque Ruiz-Carmona (Ph.D. candidate, Institute of Mathematics, Astrophysics and Particle Physics, Radboud University Nijmegen, The Netherlands) has requested AAVSO assistance with his campaign to observe a set of 20 cataclysmic variables (CVs) with the William Herschel Telescope (WHT) at La Palma TONIGHT. This campaign is identical in format to the ones successfully carried out by the AAVSO on his behalf in 2015 (AAVSO Alert Notices 524 and 527).

The full details of and instructions for this campaign are included here although the first of the two nights for which data are requested has passed.

In order for WHT to observe each of the targets safely and to maximize the science value of the observations obtained, it is essential to know whether they are in outburst or quiescence. To this end, the PI has requested our observers to obtain one image of each target on each of TWO separate nights so he may analyze them to determine the final observing list for WHT.

One image of every target should be obtained:

 - between 23 May 17:00UT and 24 May 17:00 UT
 - between 24 May 17:00UT and 25 May 17:00 UT

***The images must be posted to the thread no later than 25 May 18:00 UT.***

Observers should post their images to the thread that was created last year ("Second 17 PTF CVs campaign") in the AAVSO Campaigns & Observation Reports forum (, and include the date/time, filter, and exposure in the posting.

It is not necessary for observers to determine and submit a magnitude estimate of each target, just to obtain the images and place them where the PI can access them. Any filter may be used, and raw or reduced images of each target may be posted in the forum.

**Only one image per observer per target per night should be submitted. Please do not submit multiple images of any target obtained by you on the same night.**

An observer does not have to take images of the same targets on both nights (although that would be ideal); if conditions change between the nights, whatever images can be obtained will be extremely helpful.

The table of targets is given below. Some of the targets are quite faint, and stacking of images may be necessary. The maximum size of an image file that can be uploaded to the Forum thread is 40 MB, so if any files are larger, please trim the image(s).

PTF ID Primary Name RA (2000) Dec (2000) Mag_min Mag_outb. Type Priority
PTFS1112g GP CVn 12:27:40.85 +51:39:24.9 19.10 g' 14.30 clear UGSU+E High
PTFS1112j OV Dra 12:50:23.81 +66:55:25.5 19.00 CR 15.80 CR UGSU+E High
PTFS1114ag SDSS J143317.78+101123.3 14:33:17.78 +10:11:23.0 21.00 CV 18.60 CV CV+E High
PTFS1115x SDSS J150137.22+550123.4 15:01:37.22 +55:01:22.9 19.40 CR 16.40 CR UGSU+E  High
PTFS1115y NZ Boo 15:02:40.93 +33:34:23.7 19.60 V 13.70 V UGSU+E High
PTFS1115z OV Boo 15:07:22.22 +52:30:40.2 20.60 CV 18.00 CV CV+EA+ZZ/GWLIB High
PTFS1115ag SDSS J154453.60+255348.8 15:44:53.62    +25:53:48.9   18.00 CV 15.70 CV UG+E High
PTFS1115am QZ Ser 15:56:54.48 +21:07:19.0 17.49 V 12.70 V UGSU Medium
PTFS1115an BT CrB 15:56:56.92 +35:23:36.7 19.20 CR 16.70 CR UG+E High
PTFS1116al V844 Her 16:25:01.76 +39:09:26.5 17.50 B 12.50 B UGSU Medium
PTFS1116ae  SDSS J162520.29+120308.7 16:25:20.30 +12:03:08.8 20.00 CV 13.10 CV UGSU Medium
PTFS1116ca V592 Her 16:30:56.40 +21:16:58.5 21.4  V 12.30 V UGWZ Medium
PTFS1116s SDSS J164248.52+134751.4 16:42:48.52 +13:47:51.4 19.00 CR 15.20 CR UGSU Medium
PTFS1117b V1239 Her 17:02:13.26 +32:29:54.0 19.10 V 13.70 clear UGSU+E High
PTFS1117r MASTER OT J172758.09+380021.5 17:27:58.13 +38:00:22.5 18.00 CR 14.10 CR UG Medium
PTFS1118x V0344 Lyr 18:44:39.17 +43:22:28.1 19.00 V 13.80 V UGSU High
PTFS1119h V1504 Cyg 19:28:56.45 +43:05:37.3 17.40 P 13.50 P UGSU High
PTFS1120q SDSS J204817.85-061044.8 20:48:17.87    -06:10:45.0 20.00 CR 14.90 CR UGSU High
PTFS1120t QT Aqr 20:59:14.87 -06:12:20.5 19.3 CV 15.2 CV UG High
PTFS1121y QU Aqr 21:00:14.11 +00:44:46.0 18.8 V 16.1 V UGSU High

Observers should use a combination of AAVSO charts and charts supplied by the PI. Finder charts may be created using the AAVSO Variable Star Plotter (VSP, PDF images of PTF (Palomar Transient Factory) close-up finder charts containing the targets and offset stars chosen by the PI may be downloaded here.

Please note that there are two versions of the finding chart for PTFS1115z.

Please be sure that each image includes the offset stars, especially if you trim it so its size is less than 40MB.

Because the windows for observation by AAVSO observers are relatively short and the target list is quite long, it is recommended that observers coordinate their observing plans so that all of the targets are covered on both nights if at all possible. Please use the forum thread given above to post what targets you plan to observe; if you see that more difficult targets are not being covered and you can observe them, your doing so would be greatly appreciated.

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


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