The optical transient SDSS J163120.88+103134.0 was
discovered by the Catalina Sky Survey as an
optical transient object on May 5th, 2008.
Following its outburst announcement, I started
unfiltered CCD photometry of this variable star on
May 5/6, 2008 at CBA Belgium Observatory, using a
0.35-m f/6.3 telescope and ST-7XME CCD camera.
Independent from other observers (a/o Jochen Pietz
and Pavol Dubovsky), I detected superhumps in this
system, establishing the variable as a new member
of the UGSU-type dwarf novae.
I made follow-up observations on three successive
nights (May 05/06, 06/07 and 07/08, 2008), on the
basis of which I performed a period analysis, using
the ANOVA method in Peranso.
I added to my observations also a dataset obtained
by Tom Krajci, CBA New Mexico. The resulting time
series data contained 1096 observations and yielded
a superhump period of 0.0639 +/- 0.0002 d. The
superhump amplitude was ~0.36 mag. The phase diagram
corresponding with the above listed superhump period
is shown in fig. 3.