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[vsnet-obs 616] CVC 39 (CVAP Annual Report)

BELGIAN ASTRONOMICAL SOCIETY V.V.S. -  Working Group Variable Stars
Cataclysmic Variables Circular No.39                  1995, June 01
Ed.: T. Vanmunster, Walhostraat 1A, 3401 Landen, BELGIUM
     Internet: tvanmuns@innet.be                  TEL. 32-11-831504
     P. Van Cauteren, de Borrekenslaan 54, 2630 Aartselaar, BELGIUM
     Internet: pvancaut@innet.be                  TEL. 32-3-8774098
===================================================================

     The Cataclysmic Variables Alert Programme - Annual Report #1    
     ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 
 
Precisely one year ago, we initiated the Belgian Cataclysmic Variables 
Alert Programme (CVAP). It  is  a  cataclysmic  variables  observation 
project,  similar  to  (but complementary with)  the Recurrent Objects 
Programme of the UK-based "The Astronomer Group" (Hurst 1989). 
 
The CVAP consists of poorly observed objects,  for which  professional 
astronomers  have  shown  interest  and  have  requested assistance in 
providing  a continuous monitoring.  It  has  been  complemented  with 
objects,  for which only a few historical observations exist,  or  for 
which anomalies in predicted behaviour have been detected. 
 
This report describes the first year of CVAP activity, and  highlights 
some of the early successes achieved. Additionally, we present a  num-
ber  of extremely interesting objects, that will be added to the CVAP. 
 
 
1. CVAP activity in the period May 1994 - May 1995 
-------------------------------------------------- 

The CVAP was officially announced in  Cataclysmic  Variables  Circular 
CVC 2  (May 5, 1994). It started as a monitoring programme of 12 cata-
clysmic variables,  of  which the identification and/or classification 
was uncertain  or  unknown.  For  each  of  these  objects,  Paul  Van 
Cauteren  issued  a  set of finding charts and a sequence based on the 
Guide Star Catalog GSC.  Although  GSC-based magnitudes sometimes tend 
to  be  inaccurate,  this  approach allowed us to create sequences for 
poorly studied objects, which otherwise probably would  have  remained 
unmonitored for several more years. 
 
The  CVAP  was  first  revised  on 1994, November 1 (CVC 21).  8  more 
objects were added to the programme, and one  variable  (AR  UMa)  was 
removed. 
 
CVAP charts have been distributed  to  observers  world-wide.  We  now 
receive  regular  contributions  from amateurs in the US, UK, Hungary, 
Denmark, Germany, Japan and Belgium. 
 
Our  first  year  of CVAP activity has been characterised by some very 
nice observational results. Among the most important are : 
 
IR Lyr : this object is classified as a possible UG star in Downes and 
	 Shara (1993).  It  has  been  observed,  as part of the CVAP, 
	 during  activity  over a period of several months by 4 obser-
	 vers. Main contributions were received from Gary Poyner  (UK) 
	 and Tonny Vanmunster (B).   A  first  interpretation  of  the 
	 resulting photometric light curve clearly illustrates that IR 
	 Lyr certainly does not belong to the UG-type dwarf novae, but 
	 presumably is a semi-regular or irregular type of variable. A 
	 further  follow-up  is  required  to  precisely determine the 
	 variability type of this star. 
 
QY Per : discovered as an UG star by Hoffmeister (1966), this variable 
	 remained unobserved for many  decades.  It  finally  was  re-
	 covered  by  Tonny  Vanmunster  on  October  25,  1994,   and 
	 confirmed  by  Eric Broens (B) within minutes (CVC 20). These 
	 constituted the first visual observations since the discovery 
	 date. As a result of the outburst  notification,  Nick  James 
	 (UK)  was  able to perform accurate astrometry on the object, 
	 which showed that it was not exactly located at the  position 
	 in Downes and Shara (1993).  The outburst itself was a rather 
	 short-lived one and lasted for only 3 nights, after which the 
	 variable returned to its minimum state. 
 
UW Tri : UW Tri (= Nova Tri 1983) was discovered by Kurochkin in 1983, 
	 and  subsequently  classified as a possible nova on the basis 
	 of its light curve. The 1983  outburst  lasted  at  least  32 
	 days.  UW  Tri  was recovered in outburst on March 3, 1995 by 
	 Tonny Vanmunster (CVC 29) and  confirmed  within  minutes  by 
	 Eric Broens and Gary Poyner.  Nick James obtained a CCD image 
	 of  UW  Tri and calculated a precise position for the object. 
	 Professional astronomers in the USA, UK  and  Japan  (T. Kato 
	 and  the  Ouda Team) have closely monitored the 1995 outburst 
	 of UW Tri, which lasted for more than two weeks.  Results are 
	 currently being processed  and  might allow the determination 
	 of the exact nature of this intriguing variable. 
 
 
2. New additions to the CVAP 
---------------------------- 

Table 1 lists the new CVAP programme, which includes the  addition  of 
17  new  objects.  The newly selected targets (DK Cas, TX Tri, WY Tri, 
V336 Per,  NS Per,  DE Cnc,  RU LMi,  Leo1, T  Leo,  GW Lib, V699 Oph, 
DV Dra,  V1505 Cyg,  V1711 Cyg, FX Cep, V1089 Cyg, KM Lac) were added, 
taking into account various criteria :  
   
  - for some of them  no (or only one) reference in the Simbad Catalog  
    is  given,  indicating  that it are rather poorly studied objects,  
  - some are not confirmed as a CV, contrary to what one might  expect  
    from the classification in Downes and Shara (1993), 
  - for some the identification itself is still uncertain, 
  - for many, no visual observations seem to exist, as we could derive 
    from Vanmunster and Howell, 1995,
  - some are possible TOAD's (Howell 1995), and thus require  detailed  
    monitoring in case of an outburst detection. 
 
Finding  charts and GSC-based sequences currently are prepared by Paul 
Van Cauteren,  and shortly will be available to observers, upon simple 
request. 
 
    ____________________________________________________________          
    |                                                           | 
    |        THE CATACLYSMIC VARIABLES ALERT PROGRAMME [CVAP]   | 
    |___________________________________________________________| 
 
  VARIABLE    RA           DECL         TYPE  MAG_RANGE       REMARKS 
  NAME            [2000.0]                    MAX      MIN 
  --------    ------------------------  ----  --------------  ------- 
* DK Cas      00 18 08.39  +57 26 03.2  UGSS  15.3p   19.5:p  [2,3]        
  AS Psc      01 28 10.    +31 14 57.   UG    16.6p   21.5:p  [5,7] 
* TX Tri      01 37 37.31  +30 02 48.3  UGSS  14.5B   18.2B   [5]  
  TU Tri      01 39 15.39  +31 24 19.8  UG    14.8p  [18.0p   [5,7] 
* WY Tri      02 25 00.57  +32 59 54.9  UG    13.8p  [17.0p   [5,7] 
  KW And      02 35 18.12  +41 14 01.6  UG    14.8p   22p     [7] 
  PU Per      02 42 16.    +35 40 29.   UG    14.7p   20:p    [5,7] 
  PV Per      02 42 53.57  +38 04 02.6  UG    14.9p   20:p    [5,7] 
  UW Tri      02 45 17.2   +33 31 25.5  UGWZ? 15p    [21p     [7] 
  QY Per      03 15 37.93  +42 28 00.9  UG    14.2p  [20p     [7] 
* V336 Per    03 22 55.    +41 37 03.   UG    14.3p  [20p     [5,7] 
  V701 Tau    03 44 00.    +21 57 15.   UG:   15.0p  [21p     [5,7] 
* NS Per      04 18 44.54  +51 07 29.6  UG    15p    [18p     [5,7] 
  V650 Ori    05 31 08.25  +09 45 09.9  UG:   15.5p  [17.5p   [5,7] 
  FS Aur      05 47 48.42  +28 35 10.0  UGZ:  14.4v   16.2v    
  V421 Tau    05 48 22.98  +22 42 01.2  UG    14.5p   20p     [5,7] 
  CI Gem      06 30 05.80  +22 18 56.6  UGSU: 14.7p   18.5p   [5] 
  AQ CMi      07 14 34.84  +08 48 05.0  UG:   14.5[  [16.5p   [5,7] 
* DE Cnc      08 35 27.33  +19 45 29.2  UG    14.6p   18.0p   [5] 
* RU LMi      10 02 07.61  +33 50 59.3  UG    13.8p   19.5p   [5,7,9] 
  SS LMi      10 34 06.0   +31 07 59.   UG/N  15p    [21p     [5,7] 
* - Leo1      11 06 40.28  +01 54 49.7  CV:   14.1B           
* T Leo       11 38 27.01  +03 22 07.0  UGSU  10B     15.7B   [6,7] 
* GW Lib      15 19 55.32  -25 00 24.7  N/UG  9p      18.5p   [8] 
* V699 Oph    16 25 22.65  -04 40 25.3  UG    13.8p   18.5p   [5,10] 
* DV Dra      18 17 24.98  +50 48 14.5  UGWZ? 15.0B  [21p     [5,7] 
  IR Lyr      18 23 53.62  +39 18 58.9  ?     14.6p   16.0p 
  V358 Lyr    18 59 34.    +42 24 14.   UGWZ? 16p    [20p     [5,7] 
* V1505 Cyg   19 29 49.    +28 32 52.   UGZ   15.2p  [17.5p   [1,3,4] 
  V1289 Aql   19 38 42.25  +12 16 29.4  NL:   13p    [15.5p   [5] 
  V337 Cyg    19 59 51.    +39 13 52.   UG:   14.4p  [16.5p   [5,7] 
  IO Del      20 26 47.    +18 30 59.   UG:   15.5p  [20p     [5,7] 
* V1711 Cyg   20 55 00.70  +44 55 30.7  UG:   15.0p  [17.5p   [1,3,7] 
* FX Cep      21 03 06.19  +66 10 23.5  UGSS  15.0p   17.5p   [2,3] 
  EV Aqr      21 06 19.    +00 51 53.   UGZ:  12.1p  [14.2p   [5,7] 
* V1089 Cyg   21 44 18.    +47 54 50.   UGSS  15.0p   18.5p   [2,3,4] 
* KM Lac      22 13 49.92  +55 28 23.6  UGSS  14.8p  [17.4p   [2,3,7] 
 
 
	    Table 1 : The CVAP programme (30.05.1995) 
 
 
[1]  No references in Simbad Catalog 
[2]  Only one reference in Simbad Catalog 
[3]  Not confirmed as CV, contrary to what might be suspected by the 
     classification in Downes and Shara (1993) 
[4]  Identification uncertain 
[5]  No visual observations listed in Vanmunster and Howell (1995) 
[6]  See motivation in CVC 38 
[7]  Suspected TOAD (Howell 1995) 
[8]  Known TOAD (Howell 1995) 
[9]  Shows rather odd light curve (Howell et al. 1990) 
[10] True nature of this object unknown (Wenzel 1993) 
 
 

3. The Second Year of CVAP Activity 
----------------------------------- 

It's both hard  and  dangerous  to  make  predictions  on  cataclysmic 
variables. The same holds -even more-  for  CV  alert  programmes.  We 
nevertheless  are  very  optimistic about the CVAP future.  The recent 
additions to the programme clearly illustrate that we now have a  very 
appealing monitoring programme, and the many enthusiastic reactions we 
received  from  both  amateurs and professionals in recent months have 
stimulated us to continue our efforts.  
 
We are now starting the process of fixing objects for future inclusion 
in the CVAP.  We  hope  to  be able to identify a number of variables, 
that become brighter than magnitude 13 or so at maximum, in an attempt 
to  make  the  CVAP more attractive to amateurs with small- and medium 
sized aperture. Suggestions would be more than welcome. 
 
Finally, we feel pretty confident that one of the  highlights  of  the 
second year of CVAP activity will be the introduction of  Belgian  CCD 
work in our photometric results. We'll soon be back on this. 
     
 
References 
---------- 
 
Downes R.A., Shara, M.M.  1993, PASP, 105, 127-245
Hoffmeister, 1966, Astron. Nachr., 289, H.3, 139
Howell et al., 1990, PASP, 102, 758 
Howell, S. 1995, AJ, 439, 337-345 
Hurst, G. 1989, UK Nova/Supernova Patrol, Recurrent Objects Catalogue
Vanmunster and Howell, 1995, in preparation 
Wenzel, W. 1993, Mitt.Ver.Sterne, 12.9, 155 
 
Tonny Vanmunster