[vsnet 229] Sequence for LW Cyg

[bas@lowell.edu (Brian Skiff)]

VSnet folks,
      Appended below is a photometric sequence near the carbon star LW Cygni,
which AAVSO chartmaker Charles Scovil asked me to produce a couple of years
ago.  I worked from a preliminary (e)-scale chart supplied by Charles, which
was last annotated in 1979.  The data below were taken about one year ago,
but not analyzed until now.
     The star is not known to have a large amplitude, at least in published
work, and evidently spends most of its time around mag. 9.  (All published
photometry lies in the range 8.7 < V < 9.5.)  The star was observed first by 
Birmingham and Webb in the 1870s between mag. 9 and 10, but the evidence of
variability was meagre.  The 19th Century visual spectroscopists Duner and 
Espin both noted the "type IV" (i.e. carbon star) spectrum, but the discovery
of variability did not come until 1929 (Hoffmeister 1929, AN 236, 233).  A
June 1979 observation by Clinton B. Ford placed it as bright as m(vis) = 8.8.
     The bright M5 star HD208454, about 20' south of LW Cyg, also appears to
be a small-amplitude variable, as indicated by my measurements.  The two red
objects lie in a gorgeous starry field.
\Brian


Name               RA  (2000)  Dec         V     b-y   n  spec      remarks

HD208512        21 55 13.7  +50 29 50    9.419  3.339     C5,4      (1)
                                         9.257  3.344               (2)
HD208785        21 57 17.9  +50 29 22    7.273  0.995  1  K3II-III

BD+49 3671      21 56 09.0  +50 18 45    8.627  1.176  2
                                          .001   .005
HD208454        21 54 56.2  +50 10 00    8.871  1.321     M5        (1)
                                         8.784  1.301               (2)
BD+49 3669      21 55 00.0  +50 15 08    9.468  0.167  1

BD+49 3674      21 55 18.0  +50 13 30    9.501  0.839  1  K0

BD+49 3661      21 54 00.7  +50 33 34    9.645  0.069  2  A5
                                          .001   .006
BD+49 3662      21 54 08.4  +50 15 22    9.875  0.174  1  A2

BD+49 3665      21 54 24.4  +50 25 45   10.092  0.818  2            (3)
                                          .013   .014
BD+49 3680      21 56 21.3  +50 34 13   10.216  1.172  1            (4)

BD+49 3679      21 55 48.2  +50 32 44   10.879  0.374  2            (5)
                                          .007   .004
AG+50 1711      21 55 05.1  +50 29 31   11.719  0.264  2            (6)
                                          .019   .005
GSC 3612-0545   21 55 07.0  +50 28 37   12.464  0.416  2
                                          .029   .025
GSC 3612-0047   21 55 18.2  +50 29 11   13.302  0.536  2
                                          .042   .015


remarks:
(1)   observation on 11 Oct 1994 UT.
(2)   observation on 30 Nov 1994 UT.
(3)   = GSC 3612-0608.
(4)   = GSC 3612-1362. companions just excluded from photometer aperture.
(5)   = GSC 3612-0440.
(6)   = GSC 3612-0509.

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