A comparative study of Type II-P and II-L supernova rise times as exemplified by the case of LSQ13cuw^⋆

¹ Astrophysics Research Centre, School of Mathematics and Physics, Queen’s University Belfast, Belfast BT7 1NN, UK
e-mail: egall01@qub.ac.uk
² ESO, Karl-Schwarzschild-Strasse 2, 85748 Garching, Germany
³ Center for Astronomy and Astrophysics, Yale University, New Haven, CT 06520, USA
⁴ Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA, UK
⁵ Department of Astronomy, The Oskar Klein Centre, Stockholm University, AlbaNova, 10691 Stockholm, Sweden
⁶ School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ, UK
⁷ European Southern Observatory, Alonso de Cordova 3107, Vitacura, Casilla 19001, Santiago, Chile
⁸ INAF Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, 35122 Padova, Italy
⁹ Department of Physics, Yale University, New Haven, CT 06250-8121, USA
¹⁰ Institut für Physik, Humboldt-Universität zu Berlin, Newtonstr. 15, 12489 Berlin, Germany
¹¹ Physikalisches Institut, Universität Bonn, Nußallee 12, 53115 Bonn, Germany
¹² Millennium Institute of Astrophysics, Casilla 36-D, Santiago, Chile
¹³ Departamento de Astronomía, Universidad de Chile, 1515 Camino El Observatorio, Las Condes, Santiago, Chile
¹⁴ Las Cumbres Observatory Global Telescope Network, 6740 Cortona Dr., Suite 102, Goleta, CA 93117, USA
¹⁵ Department of Physics, University of California, Santa Barbara, Broida Hall, Mail Code 9530, Santa Barbara, CA 93106-9530, USA

Received: 11 February 2015
Accepted: 23 June 2015

Abstract

We report on our findings based on the analysis of observations of the Type II-L supernova LSQ13cuw within the framework of currently accepted physical predictions of core-collapse supernova explosions. LSQ13cuw was discovered within a day of explosion, hitherto unprecedented for Type II-L supernovae. This motivated a comparative study of Type II-P and II-L supernovae with relatively well-constrained explosion epochs and rise times to maximum (optical) light. From our sample of twenty such events, we find evidence of a positive correlation between the duration of the rise and the peak brightness. On average, SNe II-L tend to have brighter peak magnitudes and longer rise times than SNe II-P. However, this difference is clearest only at the extreme ends of the rise time versus peak brightness relation. Using two different analytical models, we performed a parameter study to investigate the physical parameters that control the rise time behaviour. In general, the models qualitatively reproduce aspects of the observed trends. We find that the brightness of the optical peak increases for larger progenitor radii and explosion energies, and decreases for larger masses. The dependence of the rise time on mass and explosion energy is smaller than the dependence on the progenitor radius. We find no evidence that the progenitors of SNe II-L have significantly smaller radii than those of SNe II-P.