2003IAUC.8061....2M

T. Matheson, P. Challis, and R. Kirshner, Harvard-Smithsonian Center for Astrophysics, report that a spectrum (range 320-880 nm) of SN 2003W, obtained by Matheson on Jan. 29.34 UT with the MMT 6.5-m telescope (+ Blue Channel spectrograph), shows it to be a type-Ia supernova well before maximum. The spectrum consists of a blue continuum with well-defined Si II and Ca II features, similar to that of SN 1994D at 12 days before maximum (Filippenko 1997, ARAA 35, 309). Adopting the NASA/IPAC Extragalactic Database (NED) recession velocity of 6017 km/s for the host galaxy, the supernova expansion velocity is 20200 km/s for Si II (rest 635.5 nm) and 27600 km/s for Ca II (rest 395.1 nm). These expansion velocities imply an age of approximately 2 weeks before maximum, based upon comparison with values presented by Jha et al. (1999, Ap.J. Supp. 125, 73).