COMMISSION 27 OF THE I. A. U.
         INFORMATION BULLETIN ON VARIABLE STARS
                      NUMBER 630

                                      Konkoly Observatory
                                      Budapest
                                      1972 February 19


         TESTS OF TWO SUSPECTED DELTA SCUTI - VARIABLES.


Frolov (1970) has listed 45 bright stars as suspected members of the delta
Scuti-class of variables and Breger (1969) determined the boundaries of the
appropriate instability strip in the M_v-(b-y) plane. Observations of two of
Frolov's stars are described here.

HR 5062 (HD 116842) was observed photoelectrically for 20 hours during 3 nights
of March & May, 1971. The 38-cm siderostat refractor fed the Pierce-Blitzstein
dual-channel photometer so that HR 5062 and the comparison star, BD +55deg1602
were monitored simultaneously. Intermediate band filters with peak wavelengths
at 4861 A and 4995 A were used. During the observing periods, the star failed
to reveal any clear variation above a scatter of slightly less than 0.03m.
Even if one assumes that the large scatter is due to possible beat phenomenon,
an unambiguous light maximum should have been detected within the 20 hours of
observation.

HR 2123 (HD 40873) has also been suspected as a light variable by Danziger &
Dickens (1967). This star was observed for 2 nights during November, 1971 for
a total of 9 hours with the refractor and photometer described above. The
Johnson & Morgan (1951) V filter was used.

BD +51deg1150 and BD +51deg1151 were used as comparison stars on different
nights. HR 2123 failed to reveal any light variability in excess of 0.01m.

These results imply that either these stars are not really pulsating or, even
if they do pulsate, that the amplitudes of their luminosity variations are not
yet large enough to establish them as members of delta Scuti-class.


GOPALA C. KILAMBI
Flower & Cook Observatory
University of Pennsylvania
Philadelphia, Pa., U.S.A.

References:

1) Breger, M. 1969, Ap. J. Supp. 19, 100. [BIBCODE 1969ApJS...19...99B ]
2) Danziger, I. J. & Dickens, R. J. 1967, Ap. J. 149, 55. [BIBCODE 1967ApJ...149...55D ]
3) Frolov, M. S. 1970, Infor. Bull. Variable stars No. 427.
4) Johnson, H. L. & Morgan, W. W. 1951, Ap. J. 114, 522. [BIBCODE 1951ApJ...114..522J ]