Observational Properties and Modelling of Hypernovae Jinsong Deng National Astronomical Observatories of China Collaborators: P. A. Mazzali (Trieste Obs. & MPA) K. Nomoto, K. Maeda (Tokyo Univ.) et al. DARK ENERGY D EN G

What are hypernovae? Why the studies? hyper-energetic supernovae (HNe) ~10 52 ergs or bigger (normal SN: ~10 51 ergs) PI SNe Woosley 1982, GRB-related energetic stellar explo. Paczynski 1998 collapsar alike GRB models Woosley et al. since 1999 a subset of Type Ic supernovae core-collapse SNe, massive CO stars some are related to gamma-ray bursts the origins of long GRBs

Hypernovae are characterized by very broad spectral lines very borad lines  high ejecta velocities (~ km/s)  large kinetic energy (~10 52 ergs)  hypernovae relatively narrow lines  low ejecta velocities (~ km/s)  normal kinetic energy (~10 51 ergs)  normal supernovae v = r / t

Hypernovae can be very bright

GRB and SN 1998bw spatial & temporal coincidene Galama et al. 1998, 1999 Kulkarni et al Iwamoto et al perculiar GRB very low E  iso  ~ ergs

Spectra and LCs of SN 1998bw

1-D model of SN 1998bw M ej ~10-11Msun E K ~ ergs M( 56 Ni)~ Msun  M MS ~35-45Msun Iwamoto et al Nature Nakamura et al ApJ Maeda, Mazzali, Deng et al ApJ

GRB and SN 2003dh Stanek et al Hjorth et al Matheson et al. 2003

1-D model of SN 2003dh Mazzali, Deng, et al ApJL Kawabata, Deng, et al ApJL Deng et al ApJ M ej ~7+/-3Msun E K ~3.5+/ ergs M( 56 Ni)~ Msun  M MS ~25-40Msun

GRB and SN 2003lw M ej ~11-15Msun E K ~6+/ ergs M( 56 Ni)~ Msun  M MS ~40-50Msun Mazzali, Deng et al in preparation Malesani et al Thomsen et al Gal-Yam et al. 2004

Collapsar model 14M ☉ He star (M ZAMS =45M ☉ ) 15.6s MacFadyen & Woosley M ☉ He star E init = ergs 7.2s Zhang, Woosley & MacFadyen 2003

Fe O 2-D features in nebular spectra SN 1998bw: Fe lines broader than O lines 56 Fe 16 O 56 F e 16 O Orientation 15 deg Maeda et al ApJL Maeda et al ApJ submitted

SN 2003jd: a HN viewed edge-on Mazzali et al Science

More [O I] profiles of SNe Ibc

SN 1997ef and 1997dq Iwamoto et al ApJ Mazalli et al ApJ Mazalli, Deng et al ApJ M MS ~ 25-30Msun E K ~ ergs M( 56 Ni)~ Msun

SN 2002ap: low-energy end of HNe Mazalli, Deng et al ApJL Deng et al in preparation M MS ~ 20-25sun E K ~ ergs M( 56 Ni)~0.08+/-0.01Msun

SN 1999as: the brightest SN ~2 － 5 Msun 56 Ni! Deng et al in preparation M MS ~ 60-80Msun E K ~25+/ ergs

E ~ M MS of SNe and HNe

M( 56 Ni) ~ M MS of SNe and HNe

Open Questions physical parameters in 2-D modelling 2-D spectrum and LC codes in development some HNe  GRBs, other HNe not viewing angle? intrinsic parameters (M, E, …)? normal Type Ic SNe  ?  GRBs 02lt/GRB (Della Valle et al. 2003) ? XRF ( Tominaga, Deng et al ApJL )? Type Ib HNe? Type IIn HNe? 97cy & 99E (CSM-I. Ia Deng et al ApJL )? 88Z ( Aretxaga et al )? radio & X-ray obs. no relativistic off-axis jets in 97dq, 97ef, 02ap, 03jd? ( Soderberg et al )