2009CBET.1710....1Y

M. Yamanaka and A. Arai, Hiroshima University, report that they obtained optical spectra (range 480-950 nm) of 2009an (cf. CBETs 1707, 1709) on Mar. 1.6 UT with the KANATA 1.5-m telescope (+ TRISPEC) at Higashi-Hiroshima Astronomical Observatory. SN 2009an exhibits a strong Si II 635.5-nm absorption feature that is blueshifted by about 14000 km/s. The spectrum shows the W-feature profile of sulfur at 520-550 nm, and the deep O I 777.4-nm feature is seen at 750 nm. The high-velocity feature of the Ca II infrared triplet clearly reaches about 22500 km/s. The spectrum is similar to that of the normal type-Ia supernova 2003du at around a week before maximum.