COMMISSION 27 OF THE I. A. U.
       INFORMATION BULLETIN ON VARIABLE STARS
                 Number 1643

                              Konkoly Observatory
                              Budapest
                              1979 July 20


  NEW LIGHT ELEMENTS FOR THE ECLIPSING BINARY XZ CMi




   Five new photoelectric minima were obtained of the
short-period eclipsing variable XZ CMi during the year
1976 at the Observatory of Sierra Nevada (Granada, Spain).

   Times of minimum were evaluated taking on account the
existence of a small asymmetry in the light curve (Breinhorst 
et al.). Observed values show considerable O-C's
against the elements published in the "General Catalogue
of Variable Stars" (I) or by Wilson (II), positive or 
negative respectively.
   min = J.D. 2428877.100 + 0.5788090d * E     (I)
   min = J.D. 2437375.7710 + 0.57881062d * E  (II)
   New elements were derived using our observations with
linear fitting by least-squares to all available minima.
As a result, a slightly shorter period was calculated and.
new elements are given by,
   min = J.D. 2442444.4017 + 0.57880845d * E (III)
   O-C's corresponding to the above mentioned elements (I),
(II) and (III), with the observed minimum times are the 
following:

   Minima        O-C(I)  O-C(II)  O-C(III)

 p 2442444.4014 +0.018d -0.0142d -0.0003d
 p 2442462.3443 +0.018d -0.0144d -0.0005d
 p 2442463.501  +0.017d -0.015d  -0.001d
 s 2442497.362  +0.018d -0.015d  -0.001d
 s 2442868.380  +0.019d -0.014d  +0.001d

(p, indicate primary minimum and s, secondary)

   The plot of computed residuals from linear ephemeris
for all available minima, suggests the existence of a small
period change as indicated, with weaker evidences, by 
Wilson.





                        A. GIMENEZ
                        V. COSTA
                        Instituto de Astrofisica
                        de Andalucia
                        Apartado 2144
                        Granada, Spain




References:


Breinhorst, R.A., Pfleiderer, J., Reinhardt, M. and Karimie,
   M.T.: Astron. & Astrophys. 22, 239 (1973). [BIBCODE 1973A&A....22..239B ]
Wilson, R.E.: Astron. J. 71, 32 (1966). [BIBCODE 1966AJ.....71...32W ]