We have investigated the pressure dependence of magnetization below 60
K up to 1.6 GPa in the low-carrier concentration system CeP showing t
wo step transitions at T = T-L and T-H under high pressure. At high pr
essure, M(P, T) exhibits a maximum at around the lower transition temp
erature T-L. This behavior implies that the magnetic state changes at
T-L. The pressure dependence of isothermal magnetization M(P) is diffe
rent above and below T-L. In fact, M(P) below T-L exhibits a maximum a
t around 1.4 GPa, whereas M(P) above T-L increases steeply with pressu
re up to 1.6 GPa.