CEP - Cepheids. Radially pulsating, high luminosity (classes Ib-II) vari-
ables with periods in the range of 1-135 days and amplitudes from
several hundredths to 2 mag in V (in the B band, the amplitudes
are greater). Spectral type at maximum light is F; at minimum,
the types are G-K. The longer the period of light variation,
the later is the spectral type. The maximum of the surface-layer
expansion velocity almost coinciding with maximum light.
CEP(B) - Cepheids (TU Cas, V 367 Sct) displaying the presence of two or
more simultaneously operating pulsation modes (usually the
fundamental tone with the period P0 and the first overtone P1).
The periods P0 are in the range from 2 to 7 days, with the ratio
P1/P0 approx. 0.71.
