COMMISSION 27 OF THE I. A. U.
        INFORMATION BULLETIN ON VARIABLE STARS
                     NUMBER 569

                                Konkoly Observatory
                                Budapest
                                1971 July 15

        HD 34409 - A SUSPECTED NEW VARIABLE STAR

      Between January 1968 and January 1970, three-colour
photo-electric photometry of the eclipsing binary AS Cam
was carried out at the University Observatory, St Andrews,
using the 40 cm Nishimura reflector. The star HD 34463 was
adopted as comparison star, and no evidence was found for
variability. However, the secondary comparison star
HD 34409 (BD +69d315) was found to vary in brightness on
four out of a total of fourteen nights. Graphs of the yellow
observations ( lambda_eff=5350 A) on these four nights are 
presented in Fig. 1. Differential magnitudes were formed in the
sense (HD 34409 minus HD 34463) and running means of two 
observations were then taken. Correction for differential 
extinction of the yellow observations was unnecessary since
the differential air mass never exceeded 0.001.
      Estimates of the (B-V) and (U-B) colour indices of
HD 34463 and HD 34409 were obtained on only one night
(JD 2440261) as follows:

----------------------------------------------
      Star    (B-V)    (U-B)  HD spectral Type
----------------------------------------------
     HD 34463 +0.19m  +0.08m       A5
     HD 34409 +0.39   +0.18        F2
----------------------------------------------

The mean errors are +0.02m in (B-V) and +0.04m in (U-B), The
colours of HD 34463 correspond well with the HD spectral
type of A5 (Johnson 1963). The (B-V) colour index of
HD 34409 is in agreement with the HD spectral type of F2
but its (U-B) value indicates an apparent ultraviolet 
depression.
      During November 1970, five spectrograms of HD 34409
were obtained at Haute Provence Observatory using the 152cm
telescope and coude spectrograph. Three of the spectrograms
have dispersions of 20A/mm and the other two were taken at
12A/mm. The spectral type of F2 is confirmed. There is no
sign of doubling of the absorption lines and no indication
of emission components. The rotational velocity is estimated 
from the profile of MgII lambda 4481 (Slettebak 1955) to be
v sini = (165+-30) km sec^-1.
      The light variations closely resemble Delta Sct
variability in appearance and duration, and the spectral
type is certainly within the appropriate range. The 
rotational velocity is, however, at the upper limit for Delta
Sct variables (Dickens 1967) but this could be compatible
with the small light amplitude.


                    [FIGURE 1]


                           R. W. HILDITCH
                       University Observatory,
                            St Andrews




References:
Dickens, R.J. 1967 Astrophys. Letters 1, 213, [BIBCODE 1968ApL.....1..213D ]
Johnson, H.L., 1963 "Basic Astronomical Data" (ed. K.Aa. Strand)
      Ch. 11. Univ. of Chicago Press.
Slettebak, A. 1955 Astrophys, J. 121, 653. [BIBCODE 1955ApJ...121..653S ]