Search for day / night and semiannual variations in the solar neutrino flux observed in the Kamiokande-II detector

Searches for possible day-night and semiannual variations of the {sup 8}B solar neutrino flux are reported based on 1040 days of Kamiokande-II data. Within statistical error, no such short-time variations were observed. The limit on the day-night difference sets a constraint on neutrino-oscillation parameters. A region defined by sin{sup 2}2{theta}{gt}0.02 and 2{times}10{sup {minus}6}{approx lt}{Delta}{ital m}{sup 2}{approx lt}10{sup {minus}5} eV{sup 2} is excluded at 90% C.L. without any assumption on the absolute value of the expected solar neutrino flux.