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LL And rare outburst

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Jeremy's picture
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LL And rare outburst

I have just posted my observation of LL And:

LL And Sep 14.902 12.8C

This is a very rare outburst of this SU Uma type dwarf nova. Follow up observations are requested, especially time series photometry

garypoyner's picture
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LL And

LL And was first seen in outburst in December 1993, and the last confirmed outburst occured in December 2008.  One other outburst was observed in June 2004 (although there have been three unconfirmed sightings visually since 2013)

LL And was fainter than 17.9CV on September 10 2021.

Nice find Jeremy.

Gary

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Outburst in 1979 ?

Hi Gary,

Could "Nova And 1979" actually have been LL And with a position error?  See VSSC #83 1995 p7 and separate thread on "N And 1979"

https://britastro.org/vss/VS0083.pdf

(Your first VSSC after you took over directorship in 1995 by the looks)

Robin

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Re: LL And

Hi Robin,

I think it probably was LL And.  I have a pre-print of a paper written by Taichi Kato in 1993 and printed in PASJ, which suggests that the 1979 Nova was indeed LL And (there were positional issues with the 1979 report).   In it Kato-san writes (about the 1979 event)...

This supposed identification, which was later confirmed by the detection of a new outburst in 1993, of a relatively bright (19 mag) quiescent counterpart naturally suggested the dwarf nova-type classification.  This information was quickly relayed to observers through the international alert networks (e.g. VSNET) and the object has been continuously monitored since then. The long-awaited next outburst finally occurred in 1993

I know I was observing it for a long time before the 1993 outburst, and was thrilled to see it for the first time then, confirming Tonny VanMunsters original detection.   Indeed Tonny (in Belgium) and I were discussing the outburst on the telephone whilst looking at it through our telescopes!   We did this several times in the 1990's during rare outburst detections.   Sadly those days are now gone - as has some of the fun of it.

Gary

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A spectrum

A spectrum (R~500)

Robin