CCD observations of the flickering of the recurrent nova RS Oph
ATel #1220; R. K. Zamanov & R. Bachev (Institute of Astronomy, Sofia, Bulgaria)
on 19 Sep 2007; 10:15 UT
Credential Certification: R. K. Zamanov (rkz@astro.bas.bg)
Subjects: Optical, Binary, Cataclysmic Variable, Nova, Variables
We have observed the recurrent nova
RS Ophiuchi in Johnson V filter using the 60 cm telescope of the
Belogradchik Astronomical
Observatory of Bulgarian Academy of Sciences. We detected variability
on time scale of minutes-to-hour (flickering). In the Table are
given the start of the
run in fractional days UT, duration of the run in minutes, number
of the CCD exposures (N), minimal
and maximal values of the V band magnitudes, amplitude of
the
variability (corrected for the observation errors), standard
deviation of RS
Oph.
   The exposure time is 120 s, and typical
accuracy of our observations is
about +/-0.01 mag, the sigma of the field stars with
similar (or lower than RS Oph) brightness is < 0.015
mag.
Date UT
|
Duration
[min] |
N
|
V
[mag]
|
A
[mag]
|
sigma
[mag]
|
2007 June 13.84
2007 July 07.91
|
66
73
|
30
27
|
10.78 - 10.97
10.81 - 11.01
|
0.19
0.20
|
0.063
0.065
|
The optical flickering of RS Oph disappeared after the 2006 recurrent
nova outburst (see ATel 832 and IBVS 5733 ) and resumed in
October 2006 (Worters et al.
2007, MNRAS, 379, 1557). Our observations confirm that the
flickering is now present and the star has brightness about
10.7-11.0 in V band.
