SN 2011dh: DISCOVERY OF A TYPE IIb SUPERNOVA FROM A COMPACT PROGENITOR IN THE NEARBY GALAXY M51 by Arcavi, I, Gal-Yam, A, Yaron, O, Sternberg, A, Rabinak, I, Waxman, E, Kasliwal, M, Quimby, R, Ofek, E, Horesh, A, Kulkarni, SR, Filippenko, A, Silverman, J, Cenko, S, Li, W, Bloom, J, Sullivan, M, Nugent, P, Poznanski, D, Gorbikov, E, Fulton, B, Howell, D, Bersier, D, Riou, A, Lamotte-Bailey, S

SN 2011dh: Discovery of a type IIb supernova from a compact progenitor in the nearby galaxy M51 by Arcavi, I, Gal-Yam, A, Yaron, O, Sternberg, A, Rabinak, I, Waxman, E, Kasliwal, M, Quimby, R, Ofek, E, Horesh, A, Kulkarni, SR, Filippenko, A, Silverman, J, Cenko, S, Li, W, Bloom, J, Sullivan, M, Nugent, P, Poznanski, D, Gorbikov, E, Fulton, B, Howell, D, Bersier, D, Riou, A, Lamotte-Bailey, S