Gamma-Ray Bursts and Supernovae Tsinghua Transient Workshop 8 Nov 2012 Elena Pian INAF-Trieste Astronomical Observatory, Italy & Scuola Normale Superiore di Pisa, Italy

GRBs are brief flashes of soft  -ray radiation (  100 keV), discovered in the 1970’s, the origin of which was not known until 1997 CGRO-BATSE

: Vela satellites : BATSE onboard the Compton Gamma Ray Observatory

The GRB distribution is isotropic

Light curves of GRBs Fluence ~ if cosmological relativistic conditions are implied: Lorentz factor  CGRO-BATSE (Fishman & Meegan 1995)

CGRO spectrum of a GRB

Bimodal distribution of GRB durations short long Different progenitors: SNe vs binary NS mergers Kulkarni 2000 Duration (s)

1 degree5 arcmin Comparison between CGRO-BATSE and BeppoSAX accuracy BATSE BSAX

: The BeppoSAX revolution Wide Field Cameras

8 hours3 days GRB970228: first detection of X-ray and optical afterglow 6 months later Costa et al Van Paradijs et al. 1997

z = 0.8 GRB (z = 1.6) V ~ 23.5 GRB (z = 0.7) GRB (z = 1.6) V(host) = 28.5 ! z = 0.7z = 0.8 Optical fields of long GRBs

GRB and Core Collapse SNe hosts observed with Hubble Space Telescope Fruchter et al.2006 CC-SNe from Hubble High-z SN Search + HST GOODS GRBs The morphologies are significantly different

Short GRB050509b (z = 0.22) Bloom et al Host galaxy

Swift localization of GRBs

Early Multiwavelength Counterparts (z = 0.937) Bloom et al (z = 6.29) (z = 1.6)

Redshift Measurement Djorgovski et al. 1999

Bloom et al. 1998,1999 Host galaxies exhibit emission lines of star formation: [O II], [O III], Balmer and Paschen series

Isotropic irradiated  –ray energy vs redshift Long GRB Short GRB

GRB model: a stellar collapse Or merger produces a relativistic jet  ~ 100  ~ 10

GRB Supernova 1998bw (Type Ic) z = Galama et al. 1998

GRB-Supernovae with ESO VLT+FORS z = z = GRB031203/SN2003lw GRB-SNe have kinetic energies exceeding those of normal SNe by an order of magnitude (e52 erg) Hjorth et al Malesani et al. 2004

X-ray Flashes

Swift was triggered by XRF on Feb , 2006 UT Prompt event afterglow Shock breakout or jet cocoon interaction with CSM, Or central engine, or synchrotron + inverse Compton ? Campana et al SN UVOT z = 0.033

VLT-FORS and Lick 3m monitoring of SN2006aj Pian et al. 2006; Mazzali et al. 2006; Ferrero et al SN2006aj (z = 0.033)

The modelling of the light curve and spectra of SN2006aj requires: And suggests that: Neutron Star?

GRB vs XRF: is the central remnant A black hole or neutron star?  ~ 100  ~ 10

Starling et al X-ray light curves of low-redshift GRBs

Shock breakout in SN2010bh (z = 0.059) Cano et al Gemini-South, Faulkes telescope, HST

GRB120422A/SN2012bz (z = 0.283) Perley et al April 2012

Light Curves of GRB and XRF Supernovae at z < 0.3 Melandri et al. 2012

GRB GRBs with supernovae GRB GRB GRB120422A

Photospheric velocities of Type Ic SNe Pian et al Bufano et al. 2012

GRB091127/SN2009nz (z = 0.49) Cobb et al Gemini/GMOS, Berger et al. 2011

Properties of SNe Ibc as f(M prog ) 2010bh 2010ah A minimum mass and energy seem to be required for GRBs: Need more data and analysis to understand trend (Courtesy: P. Mazzali) SN 2012bz/ GRB120422A SN 2012bz/ GRB120422A

light curves of the optical afterglow of the “normal” long GRB (z = 0.125) Della Valle et al Gal-Yam et al. 2006

spectra of GRB (z = 0.125): no SN features GMOS, 15 Jul 06 VLT, 29 Jul 06 Della Valle et al. 2006Gal-Yam et al. 2006

Long GRB (z = 0.089): supernova search Fynbo et al. 2006

Light curves of Ic SNe: GRB-SNe, broad-lined SNe, normal SNe -14 GRB GRB Della Valle et al Fynbo et al Gal-Yam et al. 2006

GRB060614: “long” GRB (z = 0.125) GRB050709: short GRB (z = 0.16) Comparison of temporal profiles of long and short GRBs: soft tails Swift/BAT Dt < 20 ms Gehrels et al Villasenor et al HETE2/WXM HETE2/FREGATE

GRB060505: Swift/BAT and Suzaku/WAM time profiles Time delay between BAT and WAM is inconsistent with short GRB: Dt = seconds McBreen et al. 2008

Summary and open problems All long GRBs and XRFs at z < 0.3 (with 2 exceptions) are associated with energetic spectroscopically identified Type Ic Sne. However, most broad-lined energetic Ic SNe are not associated with GRBs. SNe associated with GRBs are more luminous than both XRF-Sne and broad-lined Ic Sne with no GRB Mechanisms: Collapsar: a BH forms after the core collapses, and rapid accretion on it feeds the GRB jet. Magnetar: the NS spin-down powers a relativistic jet Is the early high energy emission due to an engine (jet) or to shock breakout? Are energetic, GRB-less Ic Sne the Progenitors of misaligned GRBs?

Simulated and analytical radio emission of GRBs 8.46 GHz Van Eerten, Zhang, MacFadyen 2010

HST Fields of GRBs (physical scale across each image is about 7 kpc) Starling et al. 2011

GRB/XRFs associated with supernovae Zhang et al. 2012, arXiv: