AL Com

Coordinates: 2000.0   R.A.= 12:32:25   Dec.= +14:20:48

AL Com is a dwarf nova of SU UMa subtype. The outbursts of this star were observed in years 1965, 1974, 1975, 1976, 1995 and 2000.

AL Com was observed in Ostrowik during 9 nights in the spring of 1995. The results of this campaign were described in one paper published in Acta Astronomica and one note in the IAU Circ No. 6161

CCD Photometry of Dwarf Nova AL Com in Superoutburst
Acta Astronomica , 1995, Vol. 45, pp. 385-398

Wojciech Pych and Arkadiusz Olech
Warsaw University Observatory, Al. Ujazdowskie 4, Warszawa, 00-478, Poland

May 24, 1995

Abstract:

We report a CCD optical photometry of a dwarf nova AL Com in superoutburst. Before superhumps occurred the light curve was highly variable with dominant periods about 41 minutes and 81.5 minutes for different nights. The period of observed superhumps is 82.5 minutes and seems to be stable. The first harmonic of the basic period is also present. We detected a weak signal corresponding to period 78.1 minutes. One of the periods 78.1 or 81.5 is suspected to be a possible signature of orbital motion in the system.

PDF version of this paper is available.

IAU Circ. No. 6162

AL COM

"Time-series observations of AL Com were collected with the 0.60-m telescope (+ Tek512 CCD camera) on three nights (Apr. 10.026-10.104, 10.805-10.896, and 11.783-11.994 UT) at the Ostrowik Observatory of Warsaw University. Observations were made in the Cousins I (first night) and V bands. We confirm the presence of coherent periodic light variations (cf. IAUC 6157). The best period for our entire data set is 81.5 +/- 0.2 min. Also, the first harmonic period (40.8 min) is clearly detectable. The peak-to-peak amplitude in the V and I bands was about 0.05 and 0.06 mag, respectively."