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Five Years of Science: GRBs and More! John Nousek (Penn State University) Neil Gehrels (Goddard Space Flight Center) International Workshop on Astronomical X-ray Optics - Prague, Czech Rep. – 6-9 Dec. 2009 1 Swift launch: 20 Nov 2004 !! 2 5th Anniversary of Swift Conference • Celebration of Swift held at Penn State, 18-20 Nov. 2009 • Attracted more than 150 participants – 1/3 Penn State, 1/3 US & 1/3 from ten other countries • Discussed impact of Swift on areas of astrophysics, and planned for future developments and science direction of the Swift Observatory 3 Swift GRB Science Swift has redefined the field of GRB science. GRB backgroud Swift comparisons Duration Host galaxies Distance distributions Energetics Beaming ARAA Annual Reviews 2009 Gehrels, Ramirez-Ruiz and Fox 4 GRB Properties Two types: Short GRBs (t < 2s) Long GRBs (t > 2s) ARAA article GRB 990123 HST image Fruchter et al. Redshift range: 0.2 - ~2 SGRBs 0.009 - 8.2 LGRBs Energy release in -rays: 1049-1050 ergs SGRBs 1050-1051 ergs LGRBs Jet opening angle: ~15 deg SGRBs ~5 deg LGRBs Both types have delayed & extended high-E emission 5 GRB Spectra afterglow with synchrotron fit prompt GRB 051111 Butler et al. 2006 6 VELA GRB discovery 1973 Compton / BATSE isotropy & inhomogeneity 2 duration classes 1991 Compton / EGRET GeV extended emission 1994 short long 7 BeppoSAX afterglow & distance 1997 Fireball Model 1997 Mészáros & Rees 1997 HETE-II GRB030329 / SN2003dh XRFs ~ 2003 8 UVOT XRT Swift Mission 3 instruments, each with: - lightcurves - images - spectra Rapid slewing spacecraft Rapid telemetry to ground BAT UVOT Position - < 1 arcsec BAT Position - 2 arcmin XRT Position - 5 arcsec BAT XRT T<10 sec . T<90 sec T<2 min 475 GRB as of 1 Nov 2009 85% with X-ray detections ~60% with optical detection 155 with redshift (41 prior to Swift) 46 short GRBs localized (0 prior to Swift) Swift Statistics Short GRB Fast Rise Exponential Decay Short GRB Swift GRB Data XRT lightcurve GRB 091029 BAT lightcurve UVOT image GRB Swift GRB Data XRT lightcurve GRB 091029 flare BAT lightcurve steep-flat-medium shape UVOT image GRB long Hard Soft Hardness Ratio short Duration (s) Time (s) Short vs Long Time (s) • short long Kouveliotou et al. 2003 13 GRB Spectroscopy z Time GRB (109 years) 8.3 6.7 6.29 5.6 5.3 5.11 GRB 080607 13.0 12.8 12.8 12.6 12.6 12.5 090423 080813 050904 060927 050814 060522 Optical Brightness K = 20 K = 19 J = 18 I = 16 K = 18 R = 21 @ 20 min @ 10 min @ 3 hrs @ 2 min @ 23 hrs @ 1.5 hrs Prochaska et al. 2008 Savaglio 2006 14 Blast from the past! GRB 090423 z = 8.29 • look back time = 13.0 billion light years Lyman break redshifted from UV to IR GROND Greiner et al Tanvir et al. 2009; Salvaterra et al. 2009 McMahon & Tanvir Evolution of Swift Operations – GRBs & More! • Original prime mission: 2004-2006 – Swift the GRB Explorer • Up to Nov. 2004 – Pre-launch: – Swift primarily a GRB detection and afterglow followup mission – Ground-breaking operations design allows immediate response to GRBs – Automated follow-up allows introduction of new GRB without new schedule – Targets of Opportunity limited to new non-Swift GRBs or rare events • Expected schedule re-plans only once / month; ToO once / week – Planning using TAKO software / five times a week • Prime mission – 2005-2006: – Execution closely follows plans, except: • XRT TEC power supply fails, forcing operations to passively maintain XRT below -50 C • Automated target process is great success allowing highly flexible and rapid ToO response 16 Swift Operations Currently • 1st mission extension: 2006-2008 – High-z GRBs and the GI Program – Swift reduces time on late afterglow followup and increases effort on finding high redshift GRBs • Swift introduces GI targets, followed by pressure for increased ToO and monitoring campaigns – TAKO planning software modified to incorporate XRT temperature control; other ancillary software improves ACS reliability – Improved ToO automation allows multiple ToOs in short period without new schedule (including nights and week-ends) – Targets of Opportunity and Monitoring Campaigns occur every day • Typical load of 4-12 ToO or Monitoring observations every day 17 Supernova Studies with Swift XRT and UVOT observations of SNe - 66 observed to date of all types (26 Ia, 18 Ibc, 22 II) - UV, optical & X-ray densely-sampled light curves - Largest sample of SN light curves in the UV - Unique UV characterizations of SN Ia's (incl UV spectra) XRT UVOT opt UVOT UV SN 2006bp (Type IIP) Supernova Lightcurves Immler et al. 2007 Brown et al. 2008 18 X-Ray SN Studies - XRT observations probe SNe environments & mass-loss rates SN 2008bo - Signature of SN shock traveling through dense shell - Shells are outer H/He-rich layers from Luminous Blue Variable phase SN 2006jc SN 2006bp Immler et al. SN 2008D Shock Breakout SN 2007uy - XRT monitoring of NGC 2770 (27 Mpc) revealed extremely luminous X-ray outburst - EX ~ 2x1046 ergs - No BAT, no radio late >> probably no jets - UVOT detection of SN rising 90 min later - SN Ib/c - Shock breakout. May occur for all SN 9 Jan 2008 Soderberg et al. 2008 Nova Studies with Swift Thermonuclear detonation of accumulated accretion on white dwarf - 25 novae observed - Rise and fall of few keV emission from shocked ejecta - Super-Soft emission in some from WD surface (kTBB ~ 30 eV) 1.6 kpc RS Oph - Extensive observations of RS Oph 2006 (~400 ksec) revealed unexpected luminous SSS state and 35 sec QPO - Earth mass ejected at ~4000 km/s into wind of companion Red Giant 21 Swift Trigger on Large Stellar Flare • BAT triggered on a stellar flare from nearby (d=5 pc) EV Lac (dM3e, Prot ~4 days) • XRT spectra show Fe K 6.4 keV emission first for an active dMe star EV Lac 25 Apr 2008 • UVOT enhancement large but unknown: instrument safed at >200,000 counts/s • Brightest stellar flare observed • Erad ~ 1038 erg • EV Lac is young magnetically active isolated star. – Previous super-flare was from binary RS CVn system, II Peg Osten et al 2007, 2008 22 BAT Sky Monitoring SWIFT J1816.7-1613 4U 0115+634 Newly discovered source (Atel #1456) Known pulsar in outburst (Atel #1426) 536 sources monitored 65 detectable on a daily basis Krimm et al ~60 with > 30 mcrab outbursts ~15 mCrab sensitivity in 1 day http://swift.gsfc.nasa.gov/docs/swift/results/transients/ 23 TOOs for Transients & GRBs - Swift can perform rapid X-ray and optical observations of transients - TOO rapidly uploaded as RA & DEC. Response time is <1 hour to 1 day - Web page for TOO requests http://www.swift.psu.edu/too.html - Duty scientists always on call for urgent TOOs - New "command from home" mode for after-hour TOOs - Expert international teams provide rapid advice * GRB follow-up (48 members) * Supernova (22 members) * CVs & novae (24 members) * Hard X-ray survey (18 members) * AGN (4 members) * GeV and TeV -rays (4 members) - Daily planning telecon to decide schedules 24 Swift Operations Ahead • 2nd mission extension: 2009-2011 – Swift: the ToO Observatory – Swift executes ~70-75 separate pointings per day • Each pointing is planned, although significant labor by human science planner to have each pointing a different target – Under an initiative approved by 2008 Senior Review, MOC has conducted an Automation Initiative to streamline science planning – Elements include: • Target management database – MySQL database to automatically ingest target information from ToO requests, target lists from GI approved proposals and GRB information from GCN circulars • More highly automated TAKO software – will allow higher automation to XRT temperature control and ACS slew behavior – Goal is to allow faster, easier science planning, with capability to increase GI monitoring campaigns and rapid ToO response to large numbers of targets 25 Conclusions • Swift has delivered a remarkably successful science mission to date, powered by an innovative operations concept that has continued to evolve as driven by scientific interest • The latest changes will enable an even more responsive observatory, giving more GI monitoring and ToO responsiveness • For Senior Review 2010, How do you suggest ways to use Swift, and how is that important for astrophysics? 26 Cosmic Timeline & Early Universe Probes z=12 z=5 z=0 27 Hint That These Probes Work z=6.29 z=6.28 GRB 050904 SDSS Quasar We Need Higher Redshift Observations • Swift & SDSS only probed the very near edge of reionization • We need a statistically significant sample that probes well into the epoch of reionization – We need to find 30-50 GRBs from 5<z<12 • ~10x what Swift found (5<z<7) – We need to find 200-400 quasars from 6<z<10 • ~10x all z>6 quasars found (6<z<6.5) z=12 z=5 Current Capabilities & Needs • Current capabilities from Swift & SDSS needed to observe high redshift objects are: – Rapid localization and observations of GRBs – Rapid notifications to enable observations by other facilities – A very large field of view for finding GRBs & quasars • BREADTH versus Depth for rare objects (Critical) • To probe high redshift objects we need: – Greater sensitivity to high redshift bursts • Redshifted gamma-ray photons into the X-ray – Prompt, uniform follow-up of afterglows in the IR (Critical) – Rapid redshift determination (in minutes) – Observations above the atmosphere are essential to eliminate terrestrial lines that confuse surveys The Solution: JANUS 1960 1980 ABC BCD D EF Testing GHI JKL XYZ Support 2000 RST TUV 1970 1980 1990 2000 2010 2020 Increasing Capabilities Space Network X-Ray Flash Monitor (XRFM): Detects & localizes high-z GRBs VWX 1960 1-20 keV, 4 sr field-of-view Near-IR Telescope (NIRT): High-z GRB & quasar spectroscopy 0.7-1.7 μm, 1″ pos, redshifts, 0.36 degree2 field-of-view, Spacecraft: Rapid communication w/ ground, rapid slewing (50°/100 sec), stable platform 31 JANUS Mission Concept – Sky Survey Mode ~400 quasars 20,000 square degree Survey 32 JANUS Mission Concept – GRB Mode ~50 GRBs 33 JANUS Objectives • • • Determine star formation history • by using ~50 GRBs Explore the coevolution of galaxies & black holes • by using ~400 quasars Determine if dominant source of reionization 34