Francisco Virgili, LJMU June 22, 2012 GRBs 2012 Liverpool C. Mundell, A. Melandri, C. Guidorzi, R. Margutti, A. Gomboc, S. Kobayashi, V. Palshin, etc GRB case study Observations Analysis Temporal Spectral (limited) Energetics Interpretation Other ultra-long GRBs GBM bg subtracted lc Gruber+ 2011 BAT emission up to ~T s XRT starting at ~T min Evans+ 2009 x 2 FTN LT KAIT Super-LOTIS SRO Gemini FTN LT KAIT Super-LOTIS SRO Gemini 3 optical peaks (451 +/- 18 s; s s) No correlation to gamma-ray peaks (~ 0s, 600s, 950 s) Steep rise/fall of 1st peak Calculate fractional signal power density (fpd) for various time slices of the KW and BAT lc. Find a variety of timescales, specifically 2 short timescales (0.5 and 1 s) and 2 long timescales (7 and 14s) R. Margutti (arxiv: ) Same analysis as full signal but on three different regimes of the BAT lightcurve: -200:250 s 250:800 s 800:1200 s Short var in 1 st and 3 rd emission episode Longer timescales in period of quiescence Vary over energy channels Softest energy range has no short timescale component Hardest scales show clear peak at low variability timescales Limited spectral information: 1 st episode: BAT+GBM 2 nd and 3 rd : GBM only Waiting on KW spectra (ideally GBM+KW) All segments fit with CPL 1 st : = -0.89, Ep=461 keV -0.89, 522 keV (joint) 2 nd : -1.2, 311 keV 3 rd : -1.58, 388 keV -1.57, 275 keV -1.49, 472 keV Gruber+ 2011 z=1.092 Energetics: Total Eiso: 6-8e53 erg Most (2e53 erg) in last emission episode Time-resolved: Most in very last peak Amati: Consistent (Amati+ 2008) No radio data (sadly)but if we did Extend analysis from Mundell+ 2007, Melandri Table from V. Palshin Also add GRB B (B.B. Zhangs talk), GRB (FTN obs) Long-lived central engine activity (~ s in RF) Similar variability timescales at early and late times No correlation of gamma and optical emission Different emission regions Indicative of RS peak followed by FS emission in optical LC Rise/fall slopes of 1 st peak Comprehensive/broadband study of prompt and any afterglow emission of ultra-long GRBs KW sample has many bursts with good spectral/temporal coverage