Monitoring the long-term variability of CVs from the Hamburg Quasar Survey

Most cataclysmic variables (CVs) have been discovered either because of their variability, strong X-ray emission, or very blue colours. We have started a program to find CVs because of their peculiar emission line spectra, selecting candidates from the Hamburg Quasar Survey. The motivation of this project has been to test whether this selection would unravel new types of CVs (which it did, e.g. the low accretion rate polars such as HS1023+3900), and we had the hope to find the many short-period CVs that CV evolution theory predicts. Interestingly enough, most of the new CVs have no or very rare outbursts, but instead of numerous short-period systems, we found a large fraction of long-period CVs, some of them clear members of the SW Sex class, but in some cases it is very difficult to unambiguously identify the CV subtype. While some systems appear to be rather normal dwarf novae, such as the recently outbursting HS0417+7445, it it is very important for the majority of the systems to gather detailed long-term light curves of these systems to better understand their nature.

The sample of HQS CVs contains by now more than 50 systems, and I will add more systems to the table below over the next days. The magnitudes are rough estimates, quite often taken from uncalibrated images or determined from spectrophotometry. As you can see, are rather faint, so it will need CCD imaging to obtain reliable magnitudes during their faint/quiescent states. Ideally, filtered observations would be best to minimise instrumental differences, but if this turns out not to be possible, filterless values will also be good. The observing strategy: to get a good long-term light curve, one would wish for one data point per night. Before starting, we need to sort out the issue of comparison stars and filters. I would probably favour V-filter, but any help/suggestions will be welcome.

An overview of the project and the related background has been given at several meetings (Göttingen 2001, Strasbourg 2004) and in the Calar Alto Newsletter (N.6, August 2003). The pages on individual objects include often links to literature via the ADS abstract service, which now provides also links to astro-ph, so you can grab a copy of those papers also without having a subscription to the astronomy journals.

If you want to know more, or have some feedback on these pages, please write me at Boris.Gaensicke(AT)warwick.ac.uk

News:
18-Oct-2006
 I have added four new dwarf nova, which have either rare outbursts or undetermined subtypes and would need regular monitoring: HS1016+3412, HS1340+1524, HS1857+7127, HS2214+2845
20-Oct-2006
 Tim Crawford reports that AAVSO charts and sequences from Arne Henden are available for a few of the HS objects. I have therefore added two more columns in the table below.
23-Oct-2006
 Tim Crawfort made charts including the Henden sequences for HS0417+7445, HS0805+3822, HS2219+1824, and HS2331+3905, which are now linked below in the table.
9-Feb-2007
 Mike Simonsen mentions that HS0618+7336 (MU Cen) has also a Henden sequence



# System
 Alt. name
 RA/Dec (2000) Type
 min.
mag 		max.
mag 		Porb
(min) 		AAVSO
chart
 Henden
sequence
1 HS0128+3547 RX J0131.4+3602 01 31 25.9 +36 02 40 CV/DN: 16.4 - - - -
2 HS0129+2933 TT Tri 01 31 59.8 +29 49 22 CV/SW - 14.7 201 - -
3 HS0139+0559 - 01 41 39.8 +06 14 38 CV/NL:/ZC: - 15.2 242 - -
4 HS0220+0603 - 02 23 01.6 +06 16 52 CV/SW 19.3 16.3 215 - -
5 HS0229+8016 - 02 35 58.0 +80 29 46 CV/NL:/ZC: 15.0 13.7 232 - -
6 HS0357+0614 KUV03580+0614 04 00 36.9 +06 22 50 CV/NL/SW - 15.4 205.5 - -
7 HS0417+7445 1RXS J042332.8+745300 04 23 33.0 +74 52 52 CV/DN/SU 18.8 13.7 104 - X
8 HS0455+8315 - 05 06 48.5 +83 19 22 CV/NL/SW - 15.0 214.17 - -
9 HS0506+7725 - 05 13 36.9 +77 28 42 CV/NL/SW: 18.5 15.1 212 - -
10 HS0551+7241 LS Cam 05 57 23.9 +72 41 52 CV/NL/SW: 19.5 16.9 204.9 - -
11 HS0552+6753 LU Cam 05 58 18.0 +67 53 46 CV/DN 17.0 14.0 216.6 X X
12 HS0618+7336 1RXS J062518.2+733433, MU Cam 06 25 16.6 +73 34 38 CV/IP - 15.1 283.2 - -
13 HS0642+5049 - 06 46 19.6 +50 45 48 CV/NL:/ZC: - 15.6 225.9 - -
14 HS0728+6738 - 07 33 41.3 +67 32 15 CV/SW - 15.3 192.34 - -
15 HS0752+6314 HT Cam 07 57 01.4 +63 06 01 CV/IP 18.0 16.5 85.98 X X
16 HS0756+1624 DW Cnc 07 58 53.1 +16 16 45 CV/IP/VY 16.5 14.5 86 X X
17 HS0758+4019 - 08 02 15.2 +40 10 47 CV/NL - 16.3 - - -
18 HS0805+3822 SDSS J080908.39+381406.2 08 09 08.3 +38 14 06 CV/SW - 15.5 192 - X
19 HS0907+1902 GY Cnc 09 09 50.6 +18 49 48 CV/DN/UG 16.3 12.0 252.64 X X
20 HS0913+0913 GZ Cnc 09 15 51.7 +09 00 48 CV/DN/IP: 16.5 13.0 127.1 X X
21 HS0922+1333 - 09 24 56.1 +13 20 52 CV/AM 17.9 - 243.4 - -
22 HS0941+0411 RX J0944.5+0357, VZ Sex 09 44 31.8 +03 58 06 CV/DN 16.5 13.2 215 X X
23 HS0943+1404 - 09 46 34.5 +13 50 58 CV/IP 19 15.5 265 - -
24 HS1016+3412 - 10 19 47.3 +33 57 52 CV/DN 18.7 15.4: 114.3 - -
25 HS1017+5319 KS UMa 10 20 26.6 +53 04 32 CV/DN/SU 16.9 12.0 97.32 X -
26 HS1023+3900 WX LMi 10 26 27.5 +38 45 01 CV/AM 17.5 - 167.6 - -
27 HS1340+1524 - 13 43 23.4 +15 09 16 CV/DN 18.5 14.2 92.66 - -
28 HS1434+2355 RX J1437.0+2342 14 37 03.3 +23 42 28 CV/DN 19.0 16.5: - - -
29 HS1449+6415 KV Dra 14 50 38.4 +64 03 29 CV/DN/SU 17.4 13.5 84.93 X X
30 HS1552+2730 RX J1554.2+2721, AP CrB 15 54 12.3 +27 21 51 CV/AM 17.5 16.5 151 - -
31 HS1607+0400 RX J1610.1+0352 16 10 07.4 +03 52 33 CV/AM - 15.8 192 - -
32 HS1804+6753 EX Dra 18 04 14.1 +67 54 12 CV/DN/UG 14.5 12.6 302.3 X -
33 HS1813+6122 - 18 14 29.7 +61 23 35 CV/SW - 15.2 203 - -
34 HS1857+7127 - 18 57 20.1 +71 31 19 CV/DN 17.2 13.9 272.3 - -
35 HS2214+2845 - 22 16 31.2 +29 00 21 CV/DN/UG 16.5 12.3 258 - -
36 HS2219+1824 - 22 21 44.7 +18 40 08 CV/DN/SU 17.5 12.0 86.2 - X
37 HS2331+3905 - 23 34 01.5 +39 21 42 CV/DN:/WZ: 16.4 - 81 - X


CV Subtypes
DN
 dwarf nova
 SU
 SU UMa dwarf nova
ZC
 Z Cam dwarf nova
 UG
 U Gem dwarf nova
NL
 novalike
 SW
 SW Sex star
AM
 polar
 IP
 intermediate polar




Monitoring Priorites

Daily monitoring urgently required (highest priority)

Frequent monitoring is desirable (medium priority)

Monitoring not desperately needed, object is covered by visual programs (lowest priority)