NSVS4484038, A contact binary system at the short-period cutoff

We present a photometric study of the short-period eclipsing binary NSVS4484038. Time-series CCD photometry of the star in the B and V band was carried out. An orbital period of 0.218551 days was determined for the eclipsing binary and a revised linear ephemeris was given. The first photometric solution of the binary system was detected through light-curve synthesis using the Wilson-Devinney method. It reveals an overcontact configuration for the system with a filling-out factor of about 10%. The mass ratio was determined to be 2.74 with an inclination of 72.°1. The less massive secondary component is found to have a higher surface temperature than the primary by about 90 K, indicating that NSVS4484038 could be a contact system of W subtype. The star is then identified to be a new member of W UMa systems at the short-period cutoff. Comparisons with known contact binaries at the short-period cutoff, the properties, and the evolutionary status of the binary system are discussed.