COMMISSION 27 OF THE I. A. U.
        INFORMATION BULLETIN ON VARIABLE STARS
                    Number 1851

                                   Konkoly Observatory
                                   Budapest
                                   1980 October 6

                                   HU ISSN 0374-0676




            HD 37819, A NEW delta SCUTI STAR




    Because of its erroneous spectral classification
(F5 Ib), HD 37819, a 8th magnitude star, has been included
in the observational program of study of the supergiant variability 
carried on at the Geneva Observatory. A variation
of short period (P ~= 4.5 h) was detected in radial velocity
the 5th of March 1980 by means of the spectrophotometer
CORAVEL (see Baranne et al., 1979) from the Geneva station
at the Haute--Provence Observatory (France). The same period
was found for the light and colour variability the 15th of
March 1980 from the Jungfraujoch Observatory (Switzerland).
Spectra at 65Angstr/mm were taken at the Haute-Provence Observatory 
with the 120 cm telescope the 21 of March 1980 (Goy,
1980). The revised spectral classification for HD 37819 is
F4 III p - delta Delphini - (Jaschek, 1980). Consequently,
HD 37819 is a new delta Scuti-type star.
    The radial velocity of HD 37819 was measured 105 times,
during the nights of March 5, 7, 9, 12, 16 and 17, 1980.
In addition, 110 photometric measurements in the U,B,V filters 
of the Geneva system were obtained during the nights of
March 15, 16 and 17, 1980.
    Fourier analysis reveals a single frequency of
5.28653d^{-1}, thus the period is
         Po = 0.18916d ~ 4.5398h


                         [FIGURE 1]

    The curves of variation in radial velocity, apparent
magnitude and Geneva colour index [B-V] are shown in the
Figure. The peak-to-peak amplitudes are respectively
13.5 km/sec, 0.103m and 0.064m.



                   G. BURKI, M. MAYOR
                   Geneva Observatory
                    CH-1290 Sauverny,
                      Switzerland



References :

Baranne, A., Mayor, M., Poncet, J.L.: 1979, Vistas in Astronomy
    23, 279 [BIBCODE 1979VA.....23..279B ]
Goy, G.: 1980, private communication
Jaschek, M.: 1980, private communication