Gamma-ray Large Area Space Telescope Gamma-ray Astrophysics and High Density e+ e- Plasma - A new application of Free Electron Laser? - Tuneyoshi Kamae SLAC, GLAST Group Gamma-ray observatories in next decade What makes GLAST-LAT unique Cosmic accelerators High density e+ e- plasma generation Possible experiments with e+e- plasma 1
Gamma-ray Sky A Simplified View 13.6eV Acceleration + photon field + relics? Onset of reheating Redshifted Big Bang Reheated atomic/mol transitions 2
>10 16 Gamma-ray Observatories in Next Decade AGASA, HiRes, A U G E R >PeV 10 14 10 12 Milagro Whipple,Cangaroo1/2 CAT, HEGRA Cangaroo3, VERITAS H E S S MAGIC TeV Energy in ev 10 10 10 8 10 6 10 4 10 2 EGRET Celeste, STACEE AGILE G L A S T OSSE I N T E G R A L CMPTL HETE2 AstroE2 RXTE, BeppoSAX SWIFT MAXI X M M AstroE2 Constellation X C h a n d r a GeV MeV kev 2000 2004 2008 2012 2016 3
Gamma-ray Observatories in Next Decade -Sensitivity - f(>e) γ/cm 2 /s 10-4 10-6 10-8 10-10 10-12 MAXI AstroE2 E -1 (diff. flux:e -2 ) Crab nebula GLAST EGRET Celeste Stacee AGILE Veritas Cangaroo3 HESS, Magic (Longer path) Milagro Whipple Cangaroo 10-14 10-4 10-2 1 10 2 10 4 Photon Energy (GeV) 4
What makes GLAST unique -EGRET s3 rd Catalog in 2 days - 100 sec All 3EG sources + ~ 80 new in 2 days Time Variability Monitoring: Flares (Blazars, AGNs, Coronas), Precessions and Glitches (Pulsars), Lensing (AGNs) 1 orbit* - GRB940217 (100sec) - PKS 1622-287 flare - 3C279 flare - Vela Pulsar - Crab Pulsar - 3EG 2020+40 (SNR γ Cygni?) 1 day^ - 3EG 1835+59-3C279 lowest 5σ detection - 3EG 1911-2000 (AGN) - Mrk 421 - Weakest 5σ EGRET source *zenith-pointed, ^ rocking all-sky scan 5
GLAST (20MeV-300GeV) Gamma-ray Observatories in Next Decade - Transient monitoring capability - 1-10 mcrab sensitivity in 1 year (1keV to 10TeV) 100s FOV MAXI on Int. Space Station (1keV-30KeV) All-sky (1 day) Air Cherenkov Array (100GeV-100TeV) 90 min Partial Survey (~3 yrs) 1 day 90 min Integral (100keV-MeV) Galactic Plane (1 yr) Galactic Plane survey (1 yr) 6
LAT Data Flow Gamma-ray Observatories in Next Decade - Observational data flow - GLAST LAT Collaboration Collaboration Science Investigation Coordinated Multiwavelength Investigations Alerts Large loads TOO commands Burst and Transient Alerts Spacecraft, GBM data Mission Ops Center GRB Coordinates Network LAT Data Status, Command Loads Schedules, Spacecraft data for archiving LAT Inst. Ops. Center LAT data handling Instrument performance Level 0,1 data processing LAT Data Archiving Level 1 & selected Level 2,3 LAT data (e.g. source catalog; diffuse bkgrd model) Science Support Center Science scheduling Mission archiving Guest Observer Support Standard product processing Guest Observers 7
GLAST-LAT Now - Balloon Flight Engineering Model successfully flown - Morning of August 4 (Saturday), 2001 240m 8
Merger fraction Themes of Gamma-ray Astronomy - Early Universe is violent - 30% 20% 1 2 Z+1 9
Blazars, Quasars, and BL Lac Obj. - Classes of γ-emitting AGN/QSO - HBL Discovery by Beppo-SAX LPQ LPQ GLAST HBL GLAST Many more γ-emitting objects (AGN, Quasar, BL Lac etc.) 10
Interplay between e + /e -, γ and B-field - Multiple wavelength picture - 11
Super-Nova Remnants - Galactic source of high energy particles - Super Nova Remnant 1006 seen by ASCA (X-ray band) Image of synchrotron radiation by high energy (~200TeV) electrons in the accelerating shock front in SN1006 12
Pulsars and Nebula - Sustained source of high energy particles - Synchrotron emission (X-ray) by high energy electrons (~100GeV) from the neutron star s magnetosphere (Magnetic induction: Pulsed) Synchrotron emission (X-ray) by high energy electrons (~100TeV) from the nebula around the neutron star s magnetosphere (Accelerating shock front: Unpulsed) The bell-shaped synchrotron nebula around the Crab pulsar (the small dot at the center of the opening of the bell-shaped nebula). A string-like flow of electrons along its rotation axis is also visible. 13
New Class of Pulsars - Radio-quiet, gamma-ray loud pulsars - Until recently, all pulsars have been discovered in Radio Band, with one exception of Geminga. In the past 5 years several pulsars have been discovered in X-ray. They are generally very weak in Radio Band. Many radio-quiet pulsars to be discovered We now expect to find many radio-quiet pulsars. We can see throught the Galaxy with gamma-rays but not with radio wave. So we will study distribution of pulsars (ie. NS s) in the Galaxy. History of star-formation activity in our Galaxy Geminga s pulse profile by EGRET Radio-loud GLAST s radio-quiet pulsar survey GC 14 The other end of Galaxy
Shock Fronts Colliding with ISM - SN1987A - 15
Gamma Ray Burst study with GLAST-GBM - Monitor GRB with wide energy coverage - Cover the classical gamma-ray band where most of the burst photons are emitted by GLAST Gamma-ray Burst Monitor (GBM) Monitor all of the sky visible from Low-Earth Orbit ( 10keV-30MeV) Monitor 40% of the sky visible from LEO (20MeV-500GeV) Identify when and where to re-point the spacecraft to optimize observations and notify other observers Simulation: Spectrum of an intense GRB by GLAST 10 kev 10 MeV 10 GeV 16
Gamma Ray Burst study with GLAST-GBM - GRB flux for > 20 MeV? - EGRET suffered severly from its dead time. GLAST can record far more photons EGRET missed ~95% of photons for bright GRBs GLAST will collect x5(area)x10-100(deadtime)=x50-500 more photons 17
Gamma Ray Burst study with GLAST-GBM - Temporal correlation btwn X-ray and γ-ray - Standard wisdom about GRB is: the more energetic, the closer to the central energy source. GLAST measures both in X-ray/soft γ-ray (GBM) and high energy γ-ray (LAT), arrowing to study temporal correlation between them. 18
Gamma Ray Burst study with GLAST-GBM - Two models of GRB: Hypernovae and mergers of compact objects - Hypernovae Explosion Model 19
Schedule - Overall Schedule as of March 2001 - Calendar Years 2000 2001 2002 2003 2004 2005 2006 2011 I-CDR SRR PDR NAR (Joint DOE/NASA M-CDR Inst. Delivery Launch Review) Formulation Implementation Ops. Build & Test Engineering Models Build & Test Flight Units Inst. I&T Inst.-S/C I&T 1 st Joint DOE/NASA of GLAST LAT Baseline Review Schedule Reserve NASA-PDR and DOE-Baseline Review Rescheduled for Jan. 8,2001 NASA announced a new launch date of March 2006 20
Photon Collider for Low Energy e+ e- Factory Helped by R. Tatchyn, P. Emma, and J. Galayda A SPPS-type photon beam at SLAC per Roman Tatchyn (SLAC) Electron energy: 28.4 GeV Peak current: 10 ka Pulse repetition rate: 120 Hz Undulator technology: hybrid/pm Undulator period: 1cm Fundamental photon energy: 533 kev Fraction of energy usable for e+e- production: ~10% Undulator length: 300m Number of periods: 30000 Vertical/horizontal emittance: 10**(-11) r-m Vertical/horizontal beam size (electron, fwhm): ~100 um Minimum photon beam size assuming 100:1 demagnification: 1 um x 1 um Electron energy beam spread (fwhm): ~1% Pulse length: ~200 fs Total in-band flux during the pulse: ~2.5x10**(24) ph/s/10%bw Number of in-band photons/pulse: 5x10**(11) ph/10%bw In-band areal photon density assuming 100:1 demagnif: 2.5 x 10**(30) ph/s/mm**2/10%bw 21