[vsnet-chat 901] Magnitudes and sequences.

[Mati Morel <morel@ozemail.com.au>]

"The more things change, the more they stay the same". 
This certainly applies to variable star sequences. Ever since I joined the
VSS,RASNZ in 1972 (and well before then, too) there has been the problem of
many variables, and not enough sequences.  This backlog  has always existed,
only the names of the variables
change.....  More than 20 years ago I started collecting copies of UBV
sequences as they appeared in the journals. There were many excellent
sequences for the southern milky way published in the Astronomical Journal
in the 1960's and 1970's especially. The intention
was to have a sufficiently large number of good sequences of, say 10-12
stars, extending to at least mag. 13, so that if a nova was found, or new
variables were added to the VSS program, then an existing published sequence
would suffice.  Experience, however, showed that most novae tended to appear
in regions without any sequence..  Nevertheless the
stategy was basically sound, and bore fruit with other types of variables. 
        It should be mentioned that a number of Catalogues of Photometric
Sequences
have been published, listing the basic parameters (not the actual data) for
hundreds
of sequences published between 1953 and 1982. Here we find that the word
"sequence" is
used very loosely, to cover a _sequence_ of only one or two stars (!!),
right through
to listings of 100+ stars. Several photometric systems are covered (but most
are UBV
sequences), and no attempt is made to evaluate the quality of each sequence,
nor its
fitness for, say visual work. Naturally, a sequence resulting from a study of a 
crowded star cluster will likely be less useful for variable star work.
        About 15 years ago I made an effort to obtain offprints of many
particular
sequences by writing to the authors. I was fairly successful, and sometimes even
received unpublished material.  However, in Supplement 2, the authors note that
"....there had been numerous complaints that sequences listed as "private
communication" had an unfortunate tendency, upon inquiry, to be
unobtainable".  So, even the mere
fact that a sequence is listed, is no guarantee that it still exists, in
such cases.
        For what it's worth, I list the Catalogues of Photometric Sequences.

YEARS        REFERENCE                      No. OF SEQUENCES
=============================================================
1953-68     Sharov, A.S. & Jakimova, N.N. 1970      450
            Shternberg Trudi, 40, 106-161
1968-73     Catalogue of Photometric Sequences      412
            Argue, A.N. & Bok, B.J. 1973
            Mimeograph, Arizona University
1973        Supplement 1                             69
            Argue, A.N. & Bok, B.J.  1973
            Mimeograph, Arizona University
1973-76     Supplement 2                            320
            Argue, A.N., Miller, E.W. 1976
            Mimeograph, Cambridge University  
1976-82     Supplement 3 
            Argue, A.N., Miller, E.W. & Warren,     1277
            W.H., Jr, 1983, Mimeograph, Ricks
            College Press

        Have any supplements been issued since 1983?  Are these publications
on-line?
        I have occasionally seen references to compilations of very faint CCD
aequences, but nothing relating to fairly bright sequences, which the above 
catalogues mainly cover.

Regards,    
       
    
/Mati

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