2010CBET.2137....1F

R. J. Foley, Harvard-Smithsonian Center for Astrophysics, reports that inspection of CCD spectra (range 305-1030 nm), obtained on Jan. 20 UT with the Magellan Clay 6.5-m telescope (+ MagE), shows that 2010E (cf. CBET 2121) and 2010F (cf. CBET 2125) are both type-II supernovae. Cross-correlation with a library of supernova spectra using the "SuperNova IDentification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) indicates that 2010E and 2010F are most similar to SN 2004et at 23 days after maximum brightness and SN 1999em at maximum brightness, respectively. Removing the host-galaxy recession velocity of 6180 km/s (found from narrow lines), the minimum of the H_alpha absorption feature is blueshifted by 6000 and 11400 km/s for 2010E and 2010F, respectively.