Dear colleagues,
TCP J04361641+562824 (aka AT 2023ayf) has been very recently detected by the
XOSS team (see TNS Astronomical Transient Report No. 170114). I have just
finished analysing my unfiltered CCD observations of TCP J04361641+5628241,
obtained on 2023, Jan 28/29 at CBA Extremadura Observatory (Spain) using a
0.40-m f/5.1 telescope and SX-46 CCD camera under clear skies.
The resulting light curve clearly shows the presence of a superhump with an
amplitude of 0.39 mag, establishing TCP J04361641+5628241 as a new SU
UMa-type dwarf nova. An accurate period analysis was not yet possible, due
to the lack of multiple superhumps within the observation window, but it
clearly is an object with a long superhump period. A rough estimate puts it
at 0.095d, but further observations are needed to firmly establish the
superhump period. The object was at mag CV = 14.7 on Jan 28th.
I will send my observations to AAVSO, CBA and VSNET for further analysis.
Best regards
Tonny
---
Tonny Vanmunster
CBA Belgium Observatory
CBA Extremadura Observatory
<http://www.cbabelgium.com> http://www.cbabelgium.com
PERANSO: The Light Curve and Period Analysis Software
http://www.peranso.com
ZTF J043616.39+562824.3 = TCP J04361641+5628241 superhump period
Tonny Vanmunster and Kiyota-san have reported observations.
The superhump period appears to be 0.08040(3) d (amplitude
0.29 mag). Other aliases are possible, but less likely.
ASASSN-23af: superhump period
Due to the short visibility, the superhump period has
not yet been pinned down. The most likely period is
0.06076(4) d (allowing aliases). The waveform was clear
and there is no ambiguity in classification. The amplitude
is small (0.12 mag) and this object may show multiple
rebrightenings.
Observers: Josch Hambsch and Berto Monard
ASASSN-23ag: superhump period
Using data since Jan. 23, the superhump period is
0.05509(3) d (amplitude 0.22 mag).
Observers: Itoh-san, Tonny Vanmunster and Josch Hambsch.
V1108 Her: complex variations
Kiyota-san's second night observations on Jan. 25
showed complex variations. Although the observing window
was short, this may have been a part of early-superhump
variations.
PNVJ06245297+0208207: brightened further, Porb?
Itoh-san's new observations indicate that the object further
brightened to 12 mag but superhumps have become weaker
(amplitude typical for AM CVn stars).
Crimean Astrophys. Obs. team also reported the rising part
and superhumps were already present on Jan. 21 (good job!).
Preliminary analysis of the initial outburst yielded
a possible period of 0.03433(4) d. Amplitude 0.02 mag and
slower rise (similar to early superhumps).
PNVJ06245297+0208207: ordinary superhumps (AM CVn, P=0.0352 d)
Itoh-san obtained long time-resolved photometry on
Jan. 25 and detected singly peaked superhumps.
These humps were also present in Tordai's observation
on Jan. 24 and Vanmunster's on Jan. 23-24 (doubly humped).
Thanks to all these observers, the rising phase of
the superoutburst was covered. The superhump period
is 0.035185(8) d (stage A+B?). The period is longer than
the oribital period of GP Com and the lack of hydrogen
lines has been confirmed. Very important finding and
object.
V1108 Her: early superhumps or superhumps
Kiyota-san reported observations on Nov. 24.
0.2-mag variations were recorded. There were two
minima within one hour. If they are early superhumps,
the amplitude is large. Observations are strongly
encouraged.