[vsnet-chat 2162] RE: EV Aqr again (fwd)

[Gary Poyner <gp@star.sr.bham.ac.uk>]

---------- Forwarded message ----------
Date: Thu, 22 Jul 1999 00:26:43 -0400
From: Shaw, Lance: <lshaw@tosco.com>
To: 'Gary Poyner' <gp@star.sr.bham.ac.uk>
Cc: "'Me@home'" <LanceShaw@aol.com>
Subject: RE: [vsnet-chat 2151] EV Aqr again


Greetings Gary.

I have come to the same potential conclusion in your message for reasons
listed below.
Could you please forward this message to the vsnet-chat group? I do not
believe this message will go through, this e-mail is not a subscriber to
the chat.



Greetings all.

First, I would like to thank everyone who replied with information on
the potential position and possible nature of EV Aquarii.
Now, where to begin?...hmm...

After looking over information from the CVAP and TAC Recurrent Objects
Programme lists, there were several stars that piqued my curiosity. One
of which was EV Aqr. I believe that I had at one time ordered a chart
from the AAVSO for this star. In the meantime, I used a chart from the
VSNET in which to make estimates with. I had also noted that on the
original VSNET chart, there was a star marked as a Var?. This I have
found, as Gary has already pointed out, to indeed be a variable and
moreover by my observation, to be of the Semi Regular type. After some
time had went by and in process of establishing a better observing
program, I added EV once again to my list of target stars. There were
several questions that I had about this object.
If it is a Z Camelopardalis star, characterised by a short outburst
interval and periodic standstills, why are there no outburst
observations in any data bases that I have researched? Although not
completely unheard of, this indeed, is quite odd. It had a relatively
bright listed outburst magnitude... This did not add up either. I had
also noticed in the interval, that Arne Henden had done some photometry
of this field. Using the sequence as extracted by Bruce Sumner to
insert, I attempted to make a chart for this variable using Guide. The
next problem occurred in that the position listed by Guide, did not
match where the position from VSNET and the CVAP showed. This too, and
again, although not usual, was somewhat strange. The catalyst was a
message from Eddy Muyllaert. Eddy had asked about a previous negative
observation that I had made of EV. What type of variable is was and
whether I had a chart for it. I explained some of the problems that I
had with this object and after making and mailing the chart to Eddy, I
looked again for more positional information. It seems the more places I
looked, the more positions I had. I then turned to Dr. Kato and Brian
Skiff to see if mayhap they had some answers or suggestions in
clarifying this mystery. Brian pointed out the reference and
clarification by Mati Morel in the IVBS. Brian did not feel it was much
help, but on the contrary, I had forgotten I already had this copy of
this Bulletin on hand. Mati's reply was helpful also. The question from
Patrick Schmeer of who wrote the original query (and I am not
invalidating it here by any means) I feel is less important as to the
'why' it was written. There are several inconsistencies here and
something is amiss. It was the message from Dr Kato, about the potential
misidentification
What I do have, and granted this is inexperienced speculation based on
what I have gathered so far,
the listed amplitude of EV Aqr agrees and is similar to the magnitude
estimates that I (and now, Gary, having observed this variable at it's
faint end) have made of the red variable in the field. As a tangent... I
would be interested to know if there are other estimates of this
variable in other databases, perhaps a curve could be constructed to
better understand the nature of this variable. I am of the subsequent
(but still quite possibly erroneous) conclusion that this red variable
and EV Aquarii are one and the same.
I again wish to thank everyone who has contributed to my query on the
position and nature of EV Aquarii. It has been an interesting and
stimulating discussion.

Clear Skies,

Lance Shaw
California, USA

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