Photometry and polarimetry, lightcurves and phase functions, spin vector and model of asteroid 10 Hygiea.

Velichko F.P. (1), Shevchenko V.G. (1), Di Martino M. (2), Oja T. (3), Erikson A. (4), Michalowski T. (5), Chiornij V.G. (1), Kalashnikov A.V. (1), Lupishko D.F. (1), R.A.Mohamed R.A. (1)

(1) Astronomical Observatory of Kharkiv University, Sumskaya str., 35, 310022 Kharkiv, Ukraine
(2) Osservatorio Astronomico di Torino, I-10025 Pino Torinese, Italy
(3) Astronomical Observatory, Box 515, S-751 20 Uppsala, Sweden
(4) DLR German Aerospace Research Establishment, 0-1199 Berlin, Germany
(5) Astronomical Observatory Adam Mickiewicz University, Sloneczna 36, PL-60 286 Poznan, Poland

Photoelectric lightcurves of asteroid 10 Hygiea from the 1990, 1991, 1993 and 1995 apparitions and polarimetric observations from the 1993 apparition are presented. The phase functions of brightness and polarization are constructed. The polarimetric data show variations of polarization over surface of the asteroid. The spin vector and ellipsoidal model of Hygiea are obtained.