AAVSO: Special Notice #15

Gary Poyner, Jeremy Shears and David Boyd (all BAAVSS) have requested
help in monitoring the dwarf novae V1316 Cyg for outbursts in the
current observing season.

Typically, V1316 Cyg experiences many brief outbursts that can last
from less than a day to 3 days with an amplitude of less than 2
magnitudes.  Poyner et al. have recently authored a paper describing
this behaviour for the Journal of the BAA. It is available online in
preprint form at this URL:

http://arxiv.org/abs/astro-ph/0605284

On June 7, 2006, shortly after the paper was accepted for publication,
the first ever detected superoutburst of V1316 Cyg was observed.  It
reached around 15.2 magnitude from a quiescence of around 17.6.

V1316 Cyg is located at 20:12:13.67 +42:45:51.4 (J2000). AAVSO charts
with Henden BV photometry are available at this URL:

http://www.aavso.org/cgi-bin/searchcharts3.pl?name=V1316%20Cyg

WARNING! Note that historically V1316 Cyg was often misidentified in
the field. There is a bright field star ('148' on the AAVSO chart) 12
arcsec distant, which may itself be variable.  To observe V1316 Cyg,
please make sure you are using the latest charts and a small
photometric aperture to avoid the companion. If you feel like it, also
report observations of the 148 comp star as "2008+42B" or "148 Comp W".

Nightly visual and CCD monitoring for both brief, normal and
superoutbursts is requested. Report observations to the AAVSO.

Latest observations in the AAVSO International Database are:

JUL 06.2090  <15.7                Vis. TDB  Dan Taylor    CANADA
JUN 30.3583   17.358  Err: 0.034  V    CTX  Tim Crawford  USA

and from the BAA:

JUL 10 10.099 17.56               Unf. PYG  Gary Poyner   ENGLAND
JUL 13 13.965 17.6                Unf. SFY  Jeremy Shears ENGLAND

Below are the main questions Poyner, Shears & Boyd are interested in
addressing with the campaign:

"1: Are the brief outbursts we have observed in 2005/2006 still
occurring, or were they precursor phenomenon to the most recent
superoutburst?

"2: Do the brief outbursts continue as before unaltered, or will the
cycle/amplitude changed because of the superoutburst?

"3: Will V1316 Cyg undergo more superoutbursts, normal
type outbursts or return to the brief outbursts?"

This special notice was compiled by: Aaron Price
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