Current status of TAMA

TAMA300, an interferometric gravitational-wave detector with 300 m baseline length, has been developed and operated with sufficient sensitivity to detect gravitational-wave events within our galaxy and sufficient stability for observations. The interferometer was operated for over 24 h stably and continuously. With a strain-equivalent noise level of h similar to 5 x 10(-21) Hz(-1/2), a signal-to-noise ratio (SNR) of 30 is expected for gravitational waves generated by a coalescence of 1.4 M-circle dot-1.4 M-circle dot binary neutron stars at 10 kpc distance. In the summer of 2000, we carried out a two-week data-taking run, called data taking 4 (DT4), collecting 160 h of data to be analysed in the search for gravitational waves. In this paper, we review the design of the TAMA300 interferometer and the results of DT4. In addition, improvements after DT4 and recent results are also reported.