Santosh Joshi - Cape Survey Project
Nainital Cape Survey Project
The Nainital-Cape Survey is a collaborative survey program to search for pulsational variability in chemically peculiar stars in the northern hemisphere. It was initiated in 1997 between the Aryabhatta Research Institute of Observational Sciences (ARIES - formerly State Observatory), Manora Peak, Nainital, India and the South African Astronomical Observatory (SAAO), Cape Town, South Africa.
The amplitudes of the light variations in these stars are so minute (<1%) that an excellent photometric site and highly sensitive and stable instrumentation are required to observe them. With care, such precision can be routinely attained at a good photometric site such as ARIES or SAAO.
These stars are designated 'CP' (for 'chemically peculiar') because their spectra exhibit abundance anomalies that manifest as extreme over- or under-abundances of various chemical elements. The spectral anomalies are caused by radiative diffusion in these stars, which pushes certain elements to the surface of the star (hence causing those elements to appear to be over-abundant) and gravitational settling of other elements in the atmosphere (hence causing those elements to appear to be under-abundant)..
For more Information click www.aries.res.in/~cns/