Daniel A. Perley
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On the Nature of GRB 050509B: a Disguised Short GRB
A&A 529, A130 (2011) Astronomy DOI: 10.1051/0004-6361/201116659 & c ESO 2011 Astrophysics On the nature of GRB 050509b: a disguised short GRB G. De Barros1,2,L.Amati2,3,M.G.Bernardini4,1,2,C.L.Bianco1,2, L. Caito1,2,L.Izzo1,2, B. Patricelli1,2, and R. Ruffini1,2,5 1 Dipartimento di Fisica and ICRA, Università di Roma “La Sapienza”, Piazzale Aldo Moro 5, 00185 Roma, Italy e-mail: [maria.bernardini;bianco;letizia.caito;luca.izzo;ruffini]@icra.it 2 ICRANet, Piazzale della Repubblica 10, 65122 Pescara, Italy e-mail: [gustavo.debarros;barbara.patricelli]@icranet.org 3 Italian National Institute for Astrophysics (INAF) – IASF Bologna, via P. Gobetti 101, 40129 Bologna, Italy e-mail: [email protected] 4 Italian National Institute for Astrophysics (INAF) – Osservatorio Astronomico di Brera, via Emilio Bianchi 46, 23807 Merate (LC), Italy 5 ICRANet, Université de Nice Sophia Antipolis, Grand Château, BP 2135, 28 avenue de Valrose, 06103 Nice Cedex 2, France Received 4 February 2011 / Accepted 7 March 2011 ABSTRACT Context. GRB 050509b, detected by the Swift satellite, is the first case where an X-ray afterglow has been observed associated with a short gamma-ray burst (GRB). Within the fireshell model, the canonical GRB light curve presents two different components: the proper-GRB (P-GRB) and the extended afterglow. Their relative intensity is a function of the fireshell baryon loading parameter B and of the CircumBurst Medium (CBM) density (nCBM). In particular, the traditionally called short GRBs can be either “genuine” short GRBs (with B 10−5, where the P-GRB is energetically predominant) or “disguised” short GRBs (with B 3.0 × 10−4 and nCBM 1, where the extended afterglow is energetically predominant). -
WHAT's BEHIND the MYSTERIOUS GAMMA-RAY BURSTS? LIGO's
WHAT’S BEHIND THE MYSTERIOUS GAMMA-RAY BURSTS? LIGO’s SEARCH FOR CLUES TO THEIR ORIGINS The story of gamma-ray bursts (GRBs) began in the 1960s aboard spacecrafts designed to monitor the former Soviet Union for compliance with the nuclear test ban treaty of 1963. The satellites of the Vela series, each armed with a number of caesium iodide scintillation counters, recorded many puzzling bursts of gamma-ray radiation that did not fit the expected signature of a nuclear weapon. The existence of these bursts became public knowledge in 1973, beginning a decades long quest to understand their origin. Since then, scientists have launched many additional satellites to study these bursts (gamma rays are blocked by the earth's atmosphere) and have uncovered many clues. GRBs occur approximately once a day in a random point in the sky. Most FIGURES FROM THE PUBLICATION GRBs originate millions or billions of light years away. The fact that they For more information on how these figures were generated, and are still so bright by the time they get to earth makes them some of the their meaning, see the publication preprint at arXiv. most energetic astrophysical events observed in the electromagnetic spectrum. In fact, a typical GRB will release in just a handful of seconds as much energy as our sun will throughout its entire life. They can last anywhere from hundredths of seconds to thousands of seconds, but are roughly divided into two categories based on duration (long and short). The line between the two classes is taken to be at 2 seconds (although more sophisticated features are also taken into account in the classification). -
From Luminous Hot Stars to Starburst Galaxies
9780521791342pre CUP/CONT July 9, 2008 11:48 Page-i FROM LUMINOUS HOT STARS TO STARBURST GALAXIES Luminous hot stars represent the extreme upper mass end of normal stellar evolution. Before exploding as supernovae, they live out their lives of only a few million years with prodigious outputs of radiation and stellar winds which dramatically affect both their evolution and environments. A detailed introduction to the topic, this book connects the astrophysics of mas- sive stars with the extremes of galaxy evolution represented by starburst phenomena. A thorough discussion of the physical and wind parameters of massive stars is pre- sented, together with considerations of their birth, evolution, and death. Hll galaxies, their connection to starburst galaxies, and the contribution of starburst phenomena to galaxy evolution through superwinds, are explored. The book concludes with the wider cosmological implications, including Population III stars, Lyman break galaxies, and gamma-ray bursts, for each of which massive stars are believed to play a crucial role. This book is ideal for graduate students and researchers in astrophysics who are interested in massive stars and their role in the evolution of galaxies. Peter S. Conti is an Emeritus Professor at the Joint Institute for Laboratory Astro- physics (JILA) and theAstrophysics and Planetary Sciences Department at the University of Colorado. Paul A. Crowther is a Professor of Astrophysics in the Department of Physics and Astronomy at the University of Sheffield. Claus Leitherer is an Astronomer with the Space Telescope Science Institute, Baltimore. 9780521791342pre CUP/CONT July 9, 2008 11:48 Page-ii Cambridge Astrophysics Series Series editors: Andrew King, Douglas Lin, Stephen Maran, Jim Pringle and Martin Ward Titles available in the series 10. -
FBE Tez Yazim Kilavuzu
İSTANBUL ÜNİVERSİTESİ FEN BİLİMLERİ ENSTİTÜSÜ YÜKSEK LİSANS TEZİ SÜPERNOVALARLA İLİŞKİLİ GAMA IŞIN PATLAMALARININ (GRB), GAMA VE OPTİK-IŞIN ÖZELLİKLERİ ARASINDAKİ İLİŞKİ Astronom Özgecan ÖNAL Astronomi ve Uzay Bilimleri Bölümü 1. Danışman Doç.Dr. A. Talât SAYGAÇ 2. Danışman Doç. Dr. Massimo DELLA VALLE Haziran, 2008 İSTANBUL İSTANBUL ÜNİVERSİTESİ FEN BİLİMLERİ ENSTİTÜSÜ YÜKSEK LİSANS TEZİ SÜPERNOVALARLA İLİŞKİLİ GAMA IŞIN PATLAMALARININ (GRB), GAMA VE OPTİK -IŞIN ÖZELLİKLERİ ARASINDAKİ İLİŞKİ Astronom Özgecan ÖNAL Astronomi ve Uzay Bilimleri Bölümü 1. Danışman Doç.Dr. A. Talât SAYGAÇ 2. Danışman Doç. Dr. Massimo DELLA VALLE Haziran, 2008 İSTANBUL Bu çalışma ..../..../ 2003 tarihinde aşağıdaki jüri tarafından ....................................... Anabilim Dalı .................................. programında Doktora / Yüksek Lisans Tezi olarak kabul edilmiştir. Tez Jürisi Danışman Adı (Danışman) Jüri Adı İstanbul Üniversitesi Üniversite Mühendislik Fakültesi Fakülte Jüri Adı Jüri Adı Üniversite Üniversite Fakülte Fakülte Jüri Adı Üniversite Fakülte Bu çalışma İstanbul Üniversitesi Bilimsel Araştırma Projeleri Yürütücü Sekreterliğinin T-935/06102006 numaralı projesi ile desteklenmiştir. ÖNSÖZ Lisans ve yüksek lisans öğrenimim sırasında ve tez çalışmalarım boyunca gösterdiği her türlü destek ve yardımdan dolayı çok değerli hocam Doç. Dr. A. Talât SAYGAÇ’a en içten dileklerimle teşekkür ederim. Tezin çeşitli aşamaları boyunca durumun hassasiyetinin bilincinde olan anneme, babama ve ağabeyime nazik ve sabırlı davranışları için ayrı ayrı teşekkür ediyorum. Bu çalışmanın başladığı ilk günlerde elime ilk makaleyi tutuşturan saygıdeğer hocam Prof. Dr. Salih KARAALİ’ye, literatür taraması yaptığım dönemlerde hemen yardımıma koşan Dr. Tolga GÜVER’e ve bulduğu önemli makaleleri benimle paylaşan Araş. Gör. Sinan ALİŞ’e çok teşekkür ederim. Çalışma sürecinin çeşitli aşamalarında tartışma fırsatı bulduğum değerli astrofizikçiler Dr. Yuki KANEKO, Dr.Andrew BEARDMORE ve Dr. -
Nanda Rea Institute for Space Science, CSIC-IEEC, Barcelona
Magnetar candidates: new discoveries open new questions Nanda Rea Institute for Space Science, CSIC-IEEC, Barcelona Image Credit: ESA - Christophe Carreau Isolated Neutron Stars: P-Pdot diagram 2 6 4 2 ⎛ 8 2R 6 ⎞ ˙ 2 2 2B R Ω sin α ˙ π ns 2 2 E rot = − m˙˙ = − PP = ⎜ 3 ⎟ B0 sin α 3c 3 3c 3 ⎝ 3c I ⎠ m 2c 3 B = e = 4.414 "1013Gauss Critical Electron Quantum B-field critic e! € Nanda Rea CSIC-IEEC € ! AXPs and SGRs general properties • bright X-ray pulsars Lx ~ 1033-1036 erg/s • strong soft and hard X-ray emission • rotating with periods of ~2-12s and period derivatives of ~10-11-10-13 s/s (Rea et al. 2007) • pulsed fractions ranging from ~5-70 % • magnetic fields of ~1014-1015 Gauss (Rea et al. 2004) (see Mereghetti 2008, A&AR, for a review) Nanda Rea CSIC-IEEC AXPs and SGRs general properties (Kaspi et al. 2003) Short bursts • the most common • they last ~0.1s • peak ~1041 ergs/s • soft γ-rays thermal spectra Intermediate bursts (Israel et al. 2008) • they last 1-40 s • peak ~1041-1043 ergs/s • abrupt on-set • usually soft γ-rays thermal spectra Giant Flares (Palmer et al. 2005) • their output of high energy is exceeded only by blazars and GRBs • peak energy > 3x1044 ergs/s • <1 s initial peak with a hard spectrum which rapidly become softer in the burst tail that can last > 500s, showing the NS spin pulsations. Nanda Rea CSIC-IEEC AXPs and SGRs general properties • transient outbursts lasting months-years • in a few cases radio pulsed emission was observed connected with X-ray outbursts, with variable flux and profiles, and flat spectra (Rea & Esposito 2010, APSS Springer Review) Nanda Rea CSIC-IEEC AXPs and SGRs general properties bursts/outbursts activity !""" &*$..+0$ (6$/&(.$ "-#$/+.)$ #2"$&,/'$ &*$&'(&$ !"" 425$/&//$ 425$&)(,$ !" 425$&,&($ "-#$&'/)$ "-#$/+/&$ "-#$&0//$ "-#$&'11$ &*$&/('$ ! '()*+,- 23*$&'&/$ "#! "-#$&).,$ !"#$%&'()$ !"#$&)..$ "#"! &*$&+(,$ !"ï& "#$! % $ !" %" ./0!"!1/23 Nanda Rea CSIC-IEEC Why magnetars behave differently from normal pulsars? • Their internal magnetic field is twisted up to 10 times the external dipole. -
The Short Gamma-Ray Burst Revolution
Reports from Observers The Short Gamma-Ray Burst Revolution Jens Hjorth1 the afterglow light-curve properties and Afterglows – found! Andrew Levan ,3 possible high-redshift origin of some Nial Tanvir 4 short bursts suggests that more than Finally, in May 005 Swift discovered the Rhaana Starling 4 one progenitor type may be involved. first X-ray afterglow to a short GRB. Sylvio Klose5 This was made possible because of the Chryssa Kouveliotou6 rapid ability of Swift to slew across the Chloé Féron1 A decade ago studies of gamma-ray sky, pointing at the approximate location Patrizia Ferrero5 bursts (GRBs) were revolutionised by the of the burst only a minute after it hap- Andy Fruchter 7 discovery of long-lived afterglow emis- pened and pinpointing a very faint X-ray Johan Fynbo1 sion at X-ray, optical and radio wave- afterglow. The afterglow lies close to a Javier Gorosabel 8 lengths. The afterglows provided precise massive elliptical galaxy in a cluster of Páll Jakobsson positions on the sky, which in turn led galaxies at z = 0.225 (Gehrels et al. 005; David Alexander Kann5 to the discovery that GRBs originate at Pedersen et al. 005; Figure ). Many ex- Kristian Pedersen1 cosmological distances, and are thus the tremely deep observations, including Enrico Ramirez-Ruiz 9 most luminous events known in the Uni- those at the VLT, failed to locate either a Jesper Sollerman1 verse. These afterglows also provided fading optical afterglow, or a rising super- Christina Thöne1 essential information for our understand- nova component at later times (Hjorth Darach Watson1 ing of what creates these extraordinary et al. -
Massive Fast Rotating Highly Magnetized White Dwarfs: Theory and Astrophysical Applications
Massive Fast Rotating Highly Magnetized White Dwarfs: Theory and Astrophysical Applications Thesis Advisors Ph.D. Student Prof. Remo Ruffini Diego Leonardo Caceres Uribe* Dr. Jorge A. Rueda *D.L.C.U. acknowledges the financial support by the International Relativistic Astrophysics (IRAP) Ph.D. program. Academic Year 2016–2017 2 Contents General introduction 4 1 Anomalous X-ray pulsars and Soft Gamma-ray repeaters: A new class of pulsars 9 2 Structure and Stability of non-magnetic White Dwarfs 21 2.1 Introduction . 21 2.2 Structure and Stability of non-rotating non-magnetic white dwarfs 23 2.2.1 Inverse b-decay . 29 2.2.2 General Relativity instability . 31 2.2.3 Mass-radius and mass-central density relations . 32 2.3 Uniformly rotating white dwarfs . 37 2.3.1 The Mass-shedding limit . 38 2.3.2 Secular Instability in rotating and general relativistic con- figurations . 38 2.3.3 Pycnonuclear Reactions . 39 2.3.4 Mass-radius and mass-central density relations . 41 3 Magnetic white dwarfs: Stability and observations 47 3.1 Introduction . 47 3.2 Observations of magnetic white dwarfs . 49 3.2.1 Introduction . 49 3.2.2 Historical background . 51 3.2.3 Mass distribution of magnetic white dwarfs . 53 3.2.4 Spin periods of isolated magnetic white dwarfs . 53 3.2.5 The origin of the magnetic field . 55 3.2.6 Applications . 56 3.2.7 Conclusions . 57 3.3 Stability of Magnetic White Dwarfs . 59 3.3.1 Introduction . 59 3.3.2 Ultra-magnetic white dwarfs . 60 3.3.3 Equation of state and virial theorem violation . -
Identifying the Host Galaxy of the Short GRB 100628A⋆
A&A 583, A88 (2015) Astronomy DOI: 10.1051/0004-6361/201425160 & c ESO 2015 Astrophysics Identifying the host galaxy of the short GRB 100628A A. Nicuesa Guelbenzu1,S.Klose1, E. Palazzi2,J.Greiner3,M.J.Michałowski4,D.A.Kann1,L.K.Hunt5, D. Malesani6, A. Rossi1,2,S.Savaglio7,S.Schulze8,9,D.Xu7,P.M.J.Afonso10, J. Elliott3, P. Ferrero11, R. Filgas12, D. H. Hartmann13, T. Krühler14, F. Knust3, N. Masetti2,15,F.OlivaresE.15,A.Rau3, P. Schady3,S.Schmidl1, M. Tanga3,A.C.Updike16, and K. Varela3 1 Thüringer Landessternwarte Tautenburg, Sternwarte 5, 07778 Tautenburg, Germany e-mail: [email protected] 2 INAF-IASF Bologna, via Gobetti 101, 40129 Bologna, Italy 3 Max-Planck-Institut für Extraterrestrische Physik, Giessenbachstraße 1, 85748 Garching, Germany 4 Scottish Universities Physics Alliance for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, EH9 3HJ, UK 5 INAF-Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy 6 Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen, Denmark 7 Physics Department, University of Calabria, via P. Bucci, 87036 Arcavacata di Rende, Italy 8 Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, 306, Santiago 22, Chile 9 Millennium Institute of Astrophysics, Vicuña Mackenna 4860, 7820436 Macul, Santiago, Chile 10 American River College, Physics and Astronomy Dpt., 4700 College Oak Drive, Sacramento, CA 95841, USA 11 Instituto de Astrofísica de Andalucía, Consejo Superior de Investigaciones Científicas (IAA-CSIC), Glorieta de la Astronomía s/n, 18008 Granada, Spain 12 Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horská 3a/22, 12800 Prague, Czech Republic 13 Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, USA 14 European Southern Observatory, Alonso de Córdova 3107, 19001 Vitacura Casilla, Santiago 19, Chile 15 Departamento de Ciencias Fisicas, Universidad Andres Bello, Avda. -
Gamma Ray Bursts, Their Afterglows, and Soft Gamma Repeaters
Gamma ray bursts, their afterglows, . and soft gamma repeaters G.S.Bisnovatyi-Kogan IKI RAS, Moscow GRB Workshop 2012 Moscow University June 14 Estimations Central GRB machne Afterglow SGR Nuclear model of SGR Neutron stars are the result of collapse . Conservation of the magnetic flux 2 B(ns)=B(s) (Rs /Rns ) B(s)=10 – 100 Gs, R ~ (3 – 10) R( Sun ), R =10 km s ns B(ns) = 4 10 11– 5 10 13 Gs Ginzburg (1964) Radiopulsars E = AB2 Ω 4 - magnetic dipole radiation (pulsar wind) 2 E = 0.5 I Ω I – moment of inertia of the neutron star 2 B = IPP/4 π A Single radiopulsars – timing observations (the most rapid ones are connected with young supernovae remnants) 11 13 B(ns) = 2 10 – 5 10 Gs Neutron star formation N.V.Ardeljan, G.S.Bisnovatyi-Kogan, S.G.Moiseenko MNRAS, 4E+51 Ekinpol 2005, 359 , 333 . E 3.5E+51 rot Emagpol Emagtor 3E+51 2.5E+51 2E+51 B(chaotic) ~ 10^14 Gs 1.5E+51 1E+51 High residual chaotic 5E+50 magnetic field after MRE core collapse SN explosion. 0 0.1 0.2 0.3 0.4 0.5 Heat production during time,sec Ohmic damping of the chaotic magnetic field may influence NS cooling light curve Inner region: development of magnetorotational instability (MRI) TIME= 34.83616590 ( 1.20326837sec ) TIME= 35.08302173 ( 1.21179496sec ) 0 .0 1 4 0 .0 1 4 0 .0 1 3 0 .0 1 3 0 .0 1 2 0 .0 1 2 0 .0 1 1 0 .0 1 1 0 .0 1 0 .0 1 0 .0 0 9 0 .0 0 9 Z 0 .0 0 8 0Z .0 0 8 0 .0 0 7 0 .0 0 7 0 .0 0 6 0 .0 0 6 0 .0 0 5 0 .0 0 5 0 .0 0 4 0 .0 0 4 0 .0 0 3 0 .0 0 3 0 .0 0 2 0 .0 0 2 0 .0 1 0 .0 1 5 0 .0 2 0 .0 1 0 .0 1 5 0 .0 2 R R TIME= 35.26651529 ( 1.21813298sec ) TIME= -
Mission Design Concept
AXTAR: mission design concept Paul S. Raya, Deepto Chakrabartyb, Colleen A. Wilson-Hodgec, Bernard F. Phlipsa, Ronald A. Remillardb, Alan M. Levineb, Kent S. Wooda, Michael T. Wolffa, Chul S. Gwona, Tod E. Strohmayerd, Michael Baysingere, Michael S. Briggsc, Peter Capizzoe, Leo Fabisinskie, Randall C. Hopkinse, Linda S. Hornsbye, Les Johnsone, C. Dauphne Maplese, Janie H. Miernike, Dan Thomase, Gianluigi De Geronimof aSpace Science Division, Naval Research Laboratory, Washington, DC 20375, USA bKavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA cSpace Science Office, NASA Marshall Space Flight Center, Huntsville, AL 35812, USA dNASA Goddard Space Flight Center, Greenbelt, MD 20771, USA eAdvanced Concepts Office, NASA Marshall Space Flight Center, Huntsville, AL 35812, USA fInstrumentation Division, Brookhaven National Laboratory, Upton, NY 11973, USA ABSTRACT The Advanced X-ray Timing Array (AXTAR) is a mission concept for X-ray timing of compact objects that combines very large collecting area, broadband spectral coverage, high time resolution, highly flexible scheduling, and an ability to respond promptly to time-critical targets of opportunity. It is optimized for submillisecond timing of bright Galactic X-ray sources in order to study phenomena at the natural time scales of neutron star surfaces and black hole event horizons, thus probing the physics of ultradense matter, strongly curved spacetimes, and intense magnetic fields. AXTAR’s main instrument, the Large Area Timing Array (LATA) is a collimated instrument with 2–50 keV coverage and over 3 square meters effective area. The LATA is made up of an array of supermodules that house 2-mm thick silicon pixel detectors. -
Mobberley.Pdf
September 18, 2008 Time: 7:31am t1-v1.0 Cataclysmic Cosmic Events and How to Observe Them For other titles published in this series, go to www.springer.com/series/5338 September 18, 2008 Time: 7:31am t1-v1.0 Martin Mobberley Cataclysmic Cosmic Events and How to Observe Them 13 September 18, 2008 Time: 7:31am t1-v1.0 Martin Mobberley Suffolk, UK e-mail: [email protected] ISBN: 978-0-387-79945-2 e-ISBN: 978-0-387-79946-9 DOI: 10.1007/978-0-387-79946-9 Library of Congress Control Number: 2008920267 # Springer ScienceþBusiness Media, LLC 2009 All rights reserved. This work may not be translated or copied in whole or in part without the written permission of the publisher (Springer ScienceþBusiness Media, LLC, 233 Spring Street, New York, NY 10013, USA), except for brief excerpts in connection with reviews or scholarly analysis. Use in connection with any form of information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed is forbidden. The use in this publication of trade names, trademarks, service marks and similar terms, even if they are not identified as such, is not to be taken as an expression of opinion as to whether or not they are subject to proprietary rights. Printed on acid-free paper springer.com Acknowledgements As was the case with my five previous Springer books, I am indebted to my fellow amateurs who have generously donated pictures of themselves, and images of their results, to this project. I am especially indebted to Seiichiro Kiyota for his con- siderable help in contacting Japanese nova patrollers who donated images of themselves for Chapter 2. -
Gamma-Ray Bursts in the Swift Era
1 Gamma-Ray Bursts in the Swift Era N. Gehrels1, E. Ramirez-Ruiz2, D. B. Fox3 [1] NASA-Goddard Space Flight Center, Greenbelt, MD 20771 [2] Dept of Astronomy and Astrophysics, UC Santa Cruz, 159 Interdisciplinary Sciences Building, 1156 High St, Santa Cruz, CA 95064 [3] Dept of Astronomy and Astrophysics, 525 Davey Laboratory, Pennsylvania State University, University Park, PA 16802 Key Words gamma rays: bursts Abstract With its rapid-response capability and multiwavelength complement of instruments, the Swift satellite has transformed our physical understanding of gamma-ray bursts. Providing high-quality observations of hundreds of bursts, and facilitating a wide range of follow-up obser- vations within seconds of each event, Swift has revealed an unforeseen richness in observed burst properties, shed light on the nature of short-duration bursts, and helped realize the promise of gamma-ray bursts as probes of the processes and environments of star formation out to the ear- liest cosmic epochs. These advances have opened new perspectives on the nature and properties of burst central engines, interactions with the burst environment from microparsec to gigaparsec scales, and the possibilities for non-photonic signatures. Our understanding of these extreme cosmic sources has thus advanced substantially; yet more than forty years after their discovery, gamma-ray bursts continue to present major challenges on both observational and theoretical fronts. CONTENTS Introduction .......................................Annu. Rev. Astron. Astrophys. 2009 1 3 Setting the Stage ....................................... 3 A Burst of Progress ..................................... 5 What is a Gamma-Ray Burst? ............................. 9 Burst and Afterglow Observations ........................... 13 Prompt High-Energy Emission ............................... 14 Afterglow Observations .................................... 19 Interpreting Prompt and Afterglow Emission .......................