FO Aqr time keeping [Observed: 49 sessions from 2004 to 2015]
Twelve seasons, from 2004 to 2015, of photometric monitoring of
the intermediate polar FO Aqr are presented and are compared with previous
observations. The ambiguities in the cycle counting can be lifted and
a new O-C diagram, spanning 34 y,r is presented, along with new ephemerides.
BG CMi time keeping [Observed: 2005-2016]
Twelve seasons, from 2005 to 2016, of photometric monitoring of the intermediate polar BG CMi are presented and are compared with previous observations. The spin up of the white dwarf is found to have undergone a major change between 1996 and 2005. There is also some evidence for sideband signals.
is also some evidence for sideband signals.
GSC 318-805 / V551 Vir: a Blazhko star [Observed: 42 sessions from 2009 to 2015]
Photometric observations of the RR Lyrae star GSC 318-905/V551
Vir are presented and analyzed. They show a Blazhko modulation with a
period of 53.9 days and evidence for irregularities. An animation showing
the Blazhko modulation is presented.
The asynchronous polar V1432 Aquilae and its path back to synchronism 
V1432 Aquilae is the only known eclipsing asynchronous polar. In this respect it is unique and therefore merits
our attention. We report the results of a 15-year campaign by the globally distributed Center for Backyard Astrophysics to observe V1432 Aql and investigate its return to synchronism. Originally knocked out of
synchrony by a nova explosion before observing records began, the magnetic white dwarf in V1432 Aql is
currently rotating slower than the orbital period but is gradually catching up. The fortuitously high inclination of
the binary orbit affords us the bonus of eclipses providing a regular clock against which these temporal changes
can be assessed. At the present rate, synchronism should be achieved around 2100. The continually changing trajectory of the accretion stream as it follows the magnetic field lines of the rotating white dwarf
produces a complex pattern of light emission which we have measured and documented, providing comprehensive
observational evidence against which physical models of the system can be tested.
VY Cet: a contact binary in a ternary system [Observed: 26 Dec 2006, 3 Nov 2007, 30 Jan 2009, 31 Oct 2014]
Time series of this contact binary in a ternary system are presented.
3 ToMs are measured along with the B-V and V-Rc colors.
AO Psc time keeping [Observed: 74 sessions from 2004 to 2014]
Eleven seasons, from 2004 to 2014, of photometric monitoring of the intermediate polar AO Psc are presented and are compared
with previous observations. The spin up of the white dwarf is found to be
slowing down. The amplitudes of the modulated and non-modulated components of the
brightness are found to have undergone a major change in 2007.
AR Ser: photometric observations of a Blazhko star [Observed: 2010-2014]
Photometric observations in 2010-2014 of the RR Lyrae star AR Serpentis are presented and analyzed. Two Blazhko modulations of comparable amplitude are detected, with the periods 89 and 108 days, and with evidence for irregularities.
MR Ser: a polar cataclysmic [Observed: 16 April, 17, 18 July 2014]
Photometric observations of the polar cataclysmic MR Ser are presented and compared
with the ephemeris.