Mészáros, Heid 04

GRB• Swift Progress Report & Prospects• High Energy Photons & Neutrinos

Peter MészárosPennsylvania State University

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The Time GapSwift

Beppo SAX data

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Swift:The Gamma-Ray burst Explorer Mission

• Objectives– Determine origin of GRBs– Use GRBs to probe Universe– Perform hard X-ray survey

• Rapidly re-pointing spacecraft– ~ 1 minute response

• Data distributed immediately (seconds) to astronomical community world-wide

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The Swift MIDEX

• Prime Institution: NASA-GSFC (Neil Gehrels, PI)

• Lead University Partner: Penn State (PSU)

• Countries Involved: USA, Italy, UK

• Spacecraft Partner: Spectrum Astro

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Swift Instruments

• Burst Alert Telescope (BAT)– CZT detectors– Most sensitive gamma-ray

imager ever• X-Ray Telescope (XRT)

– Arcsecond GRB positions– CCD spectroscopy– Jet-X mirrors, XMM Detectors

• UV/Optical Telescop (UVOT)– Sub-arcsecond imaging– Grism spectroscopy– 24th mag sensitivity (1000 sec)– Finding chart for other

observers– Copy of XMM OM

BAT

XRT

Spacecraft

UVOT

Spacecraft

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Swift: new multiwavelengthrapid-response observatory in space

• GRB database with good statistics :

100-150 GRB/year with good localization,

plus another 100-150/year unlocalized

• Observations immediately follow GRB when emission is brightest

• Rapid identification of counterparts

– Arcsec position immediately to ground for spectroscopy

– Sub-arcsec relative positions for hundreds of bursts for host galaxy ID and GRB origin determination

• Measure distances (redshifts) for hundreds of bursts

• Multiwavelength afterglow observations on all timescales• Low Earth orbit: 600 km altitude, 20 degree inclination• Rapid dissemination of data• Launch in October 2004

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Observing Scenario1. Burst Alert Telescope triggers on GRB, calculates position on sky to < 4 arcmin2. Spacecraft autonomously slews to GRB position in 20-70 s3. X-Ray Telescope determines position to ~3 arcseconds

4. UV/Optical Telescope images field, transmits finding chart to ground

BAT Burst Image

T<10 sec

BAT Error Circle

XRT Image

T<90 sec T<300 sec

UVOT Image

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Why a Burst Alert Telescope?

To rapidly locate a wide range of Gamma Ray Bursts

BAT burst detection abilities:•Sensitive to energy range containing GRB peak energy fluxes (15-150 keV)•Accurately positions GRB of short and long durations (milliseconds to minutes)•Large field of view (2 Steradian)•Large effective area (5200 cm2:

5x more sensitive than BATSE)•Sufficient angular resolution to rapidly localize within XRT, UVOT fields of view (17’ full width, 1-4’ centroid)

Telescope Coded Mask Timing Resolution 20 usec Detector Cadmium Zinc Telluride Detector Format 128 pixels x 256 readout

circuits Detector Readout Modes

Burst mode, survey mode

Field of View 2 Steradian, partially coded Pixel Scale 17 Arcmin Sky Pixel Position Knowledge Centroid to 5 Arcmin Energy Range 15keV to 150keV Effective Area 5200 cm2 Sensitivity 0.2 photons/cm2/sec Operation Autonomous

BAT Characteristics

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BAT Instrument

CZT Detectors

Detector Module

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The Burst Alert Telescope (BAT)

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Image Taken during Calibration

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Why an X-ray Telescope?

A: because > 80% of GRBs have X-ray afterglowsGRB Afterglow Detections

Telescope 3.5 m Wolter I Telescope PSF 15 arcsec HPD @ 1.5 keV Detector EEV CCD-22 Detector Format 600 x 600 pixels Detector Readout Modes

Photon counting, Imaging, & Timing

Field of View 23.6 x 23.6 arcmin Pixel Scale 2.36 arcsec / pixel Energy Range 0.2 - 10 keV Effective Area 110 cm2@ 1.5 keV Sensitivity 2x10-14 erg cm-2s-1 in 104 s 1 cps per milliCrab Position Accuracy 2.5 arcseconds (2 sigma) Operation Autonomous

XRT CharacteristicsTriggerGRB Mission X-ray Optical Radio

970111 Beppo SAX X970228 Beppo SAX X X970402 Beppo SAX X970508 Beppo SAX X X X970616 BATSE/RXTE X970828 BATSE/RXTE X ?971214 Beppo SAX X X971227 Beppo SAX X980326 Beppo SAX ? X980329 Beppo SAX X X X980425 Beppo SAX ? SN X980515 Beppo SAX X980519 Beppo SAX X X X980613 Beppo SAX X X980703 BATSE/RXTE X X X981226 Beppo SAX ? X990123 Beppo SAX X X X

Afterglow

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1) Brilliant Flash

Use Imaging Mode: 0.1 s exposure time integrated image provides accurate centroids for Fx<26 Crabs

Swift XRT

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Source Centroids

2.5 arcsec centroids

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RedshiftMeasurement

Spectral Parameters:• I(E) = A E-2.0

• NH = 2.5 x 1022

• Eline = 6.4 keV• R = 150 cps

(150 milliCrab source)• t = 100 s

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XRT SensitivityUse Timing Mode

and/or Photon-Counting Mode:

Timing Mode: Accurate Light Curves and Spectroscopy for 20 mCrabs < I < 8.5 Crabs

Photon-Counting Mode: Accurate Position, Lightcurve, and Spectroscopy for I <20 mCrabs

XRT Sensitivity Limit

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XRT Integration to Spacecraft

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Why a UV/Optical Telescope?

A: subarcsecond positions, redshifts

Telescope 30 cm modified Ritchy-Cretien F-number 12.7 Telescope PSF Diffraction-limited Detector Photon-counting intensified CCD Detector Format 2048 x 2048 virtual pixels Field of View 17 x 17 arcmin Pixel Scale 0.50 arcsec / pixel Bandpass 170 – 650 nm Spectroscopy 2 grisms + 6 broad band colors Sensitivity B=24th magnitude in 103 s (white light) Position Accuracy 0.3 arcseconds @ 350 nm Operation Autonomous

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UVOT: Heritage Hardware

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Wavelength response of UVOT

Grisms

Broadband filters

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UVOT Improved UV Response

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UVOT Integration to Spacecraft

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Swift Ground System

Malindi

Science Center GSFC

MissionOperations Center

(MOC)PSU

TDRSSPayload

Spectrum AstroRapid Autonomous Slewing

BATXRT

UVOT

Spacecraft

User Community

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Latest status

• As of June 5 ’04:• The Swift observatory is nearing completion

of its thermal vacuum testing with no major problems uncovered. This is the last of many environmental tests the instruments and observatory have been subjected to. If all continues to go well, the observatory will be shipped to Florida in mid-June.

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Swift is scheduled to launch on a Delta II rocket in early October 2004

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The Swift Explorer in Orbit

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Short(tg d 2 s)

Long(tgt 2 s)

GRB:→ (current paradigm)

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Jet (outside the star) → shocks• Shocks expected in any

unsteady supersonic outflow (esp. in a non-vacuum environment)

• Internal shocks: fast shells catch up slower shells (unsteady flow)

• External Shock: flow slows down as plows into external medium

• NOTE: “external” and “internal” shocks might be expected also while jet is inside star, as well as after it is outside the star.If inside: gs do not escape (but n can)if outside: gs do escape (and n too)

ò“Internal” shocks

“external” shock →

reverse forward

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Poynting flow dissipation

• Internal shocks are replaced by reconnectivedissipation for prompt GRB emission

• External forward similar, reverse shock needs other explanation

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Cosmology with GRBs?High-z GRB distance measures

Ø Fe Ka

∞ Gal.H abs

Lamb, Reichart 00

•XR cont: detect with Swift for zd 20 @ t d 1 dy•Fe Ka XR line unabsorbed by gal. for zd20•Swift det. Fe Ka to zd3 @ td3 hrs , 3s level•XMM det. Fe Ka to zd15 @ td1day, 3s level

•Positive K-correction: → flux ~ constant at zt5

•Optical/UV: Ly a cutoff →redshift out to zd5 for Swift•Forward shock exp. fluxesØ

XR

ò Meszaros, Rees 03 ApJ 591, L91

O/IR

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Reverse Shocklight-curve

Gou, et al, ApJ in press, astroph/0307489

R

F

V-band

K-band

• Brief reverse O/IR light curve is brighter (while it lasts) than forward l.c

• At high-z, reverse l.c. lasts longer (in obs. frame)

nFn Sy (forw)

Sy (rev)

X,g0

n

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IR & XR hi-z detectability

JWST

ROTSE

O/IR zxdetectability

XR detectability Ø

Chandra

Swift

V-band

K-band

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Fe line detectability

• Top: Swift. Lx0=1050 erg/s, T=40s, EW=1.0keV

• Bottom: XMM Epic, Lx0=1050 erg/s, T=20s, EW=0.5keV

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GeV gemission from

GRB, PSR,SNR,

other galactic, extragalactic

&un-id sources• GeV: space obs. (SAS-2, HEAO-A4, Kvant….)• EGRET spark chamber: 5 GRB, 6 PSR & 60 blazars @d10GeV• + ~25 other Unidentified EGRET g-ray sources

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Two EGRET spark chamber GeV Bursts

GRB 970217

• >10 GeV photon flux can last for t 1 hr,

start with MeV trigger• Energy Fluence

F0.1-10 GeV ~ F0.1-10 MeV

GRB 930131

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Simplest “delayed” GeV g mech.

• GeV emission seen, start ~ same time as MeV trigger, but lasting t 1 hr: → could be a) internal shock synchrotron

→ normal duration MeV to dGeVb) external shock (moder. G, low next)

IC → t GeV to TeV, lasts ~mins-hr(Meszaros & Rees 1994 MNRAS 269, L41)

• Other possib (Katz 94) : proton impact on bin. comp.* pp → g

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GeV-TeV photons from GRB• Internal shocks: gg→e≤ ,

tgg¥1 @ Egt G2300 GeV

→ pair cutoff in spectrï get info about r sh(compactness,tgg)

• In ext.shock, tgg§1 on GRB target g;

• test if shock is int. or ext;test bulk Lorentz factor,

shock accel efficiency, magnetic field in shock (max. e≤ energy? →size of accel region)

Baring 1999

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GRB 941017 : pg signature?• Hard (10-200 MeV) comp. in

EGRET TASC calorimeter notcompatible w. BATSE MeV fit(but in 26 other bursts a single BATSE/TASC fit works well)

• Hard comp. more prominent in time → pg signature? might explain delay, hardness

• Alternative: could be IC, in regime where IC sp is harder than sync PL ; e.g. scatt. of lower energy synch. asymptote; or observe IC region where electrons with a range of energies scatter off a range of photon energies (Granot,Guetta, astroph/0309231)

t<14 s

t <47 s

t < 80 s

t < 113 s

t < 211 s

Gonzalez, Dingus et al, 03, Nature 424, 749

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GLAST : LAT (Stanford +)

• LAT: launch exp ’06,Delta II, 2-300 GRB/2yr

• Pair-conv.mod+calor.• 20 MeV-300 GeV, DE/Ed10%@1 GeV

• fov=2.5 sr (2xEgret), q~30”-5’ (10 GeV)

• Sens t2.10-9ph/cm2/s(2 yr; > 50xEgret)

• 2.5 ton, 518 W Also on GLAST: GBM (next slide)

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Hadronic processes – tTeV?basic p,g→ UHE n,g

• If protons present in jet → they are also Fermi accelerated (as are e-)• p,g→ π±→µ± ,nµ→e±,,ne,nµ (∆-res.: Ep Eg ~ 0.3 GeV2) • → En,br ~ 1014 eV for MeV gs (int. shock)

→ En,br ~ 1018 eV for 100 eV gs (ext. rev. sh.) ICECUBE

• →p0 →2g→ gg cascade GLAST, ACTs..(Waxman-Bahcall 1997;99; Boettcher-Dermer 1998; 00; )

• Test hadronic content of jets (are they pure MHD/e≤ …?)• Test acceleration physics (injection effic., ee, eB..)• Shock radius: gg cascade cut-off: eg d GeV (internal shock)

eg d TeV (ext shock/IGM)Different gg cut-off due to π compactness param. (tgg , Rsh)

→ photon cut-off: diagnostic for int. vs. ext-rev shock

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TeV g Detection Status

• Milagrito :Tentative ò (3s) TeV detection ;FTeV ~10 FMeV ; but, no z (abs? dd100 Mpc?)

Atkins etal, 00, ApJL..

• Tibet array: superpose 50-60 ∫ bursts in time-coincid. w. MeV: joint TeVdet. significance 6s ?

(Amenomori et al AA ‘96)

• GRAND: GRB 971110ò TeV reported at 2.7s

(Poirier et al PRD 03, aph/0004379)

Log10(prob)

Num

ber

of G

RB

s

0

2

4

6

8

10

12

14

-6 -5 -4 -3 -2 -1 0

GRB 970417a

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gg Opacity of the Universe• In all but the densest

(veiled) AGN sources (e.g. gal.nuc?), tgg§1 for >TeV on “local”target photons, but..

• In IGM, tgg¥1 for >TeVon IR bkg g(Dd100Mpc) →test IR bkg spectral density,

• constrain early star formation rate & z-distr of SFR, LSS, cosmology

Coppi & Aharonian ‘97

g

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GeV-TeV(PeV?)

Photonsfrom GRB

• Include synchrotron self-absorption in internal shocks ïgg absorption thins out at UHE energies

(Razzaque, Meszaros, Zhang aph/0404076, apj in press)

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GeV-TeVGRB spectra

• Primary escaping spectra of internal shock are softer (cutoffs 30-300 GeV) than for external shock

• Primary spectra are further reprocessed by interaction with diffuse IR bkg and CMB

• Secondary reprocessed radiation easier to detect since softer (HESS, GLAST range) and longer duration.

• Delay of secondary rad’ndepends on IGM magnetic field(best prospects:Bd10-17G)

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GeV-TeV g experiments underway

MILAGRO

CherenkovTelescopes

≠ Water

Air →∞ ∞

HESS

MAGIC& HEGRA

VeritasVERITAS

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Point Source Sensitivities• MAGIC: La Palma (Munich)

Monoc. 1x17m, >30 GeV, ‘01• HESS: Namibia (Heidelberg)

Stereo 4x12m, > 50 GeV, ’02 • CANGAROO-III: Austral(Tokyo)

Stereo 4x10m, >50 GeV, ’03• VERITAS: Arizona (SAO)

Stereo 7x10m, >50 GeV, ’05• STACEE: Sandia (UCLA/Chic)

solar tower, 20-300GeV, ’01• MILAGR(ITO)O, LANL, NM

water, > 20 GeV, A~5.107 cm2

• GLAST (LAT): space (Stanford)Silicon, 20 MeV-300 GeV, ‘06

HESS

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UHE n (&g) in GRB4 possible collapsar-jet sites• 0) ôat collapse, make GW + thermal ns• 1) ô If jet outflow is baryonic, have p,n

→ p,n relative drift, pp/pn collisions→ inelastic nuclear collisions→ VHEn (GeV)

• 2) ôShocks while jet is inside ø can accel. protons → pg, pp/pn collisions→ UHEn (TeV)

• 3) ôShocks outside ø accel. protons→ pg collisions (+pp/pn - if supranova )→ UHECR , UHEn, UHEg

(d1020 , 1014-1018, t109 eV)

• 4) If supranova (SN >2 days before GRB)→ pg, pp of jet protons on shell targets→ UHEn (> TeV)

GW

p,n

pg, pp

pg

1

2

3

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(2) Jet inside star:

GRB n,g Precursor

4 5 6 7 8 9

�9.5

�9

�8.5

�8

�7.5

�7

�6.5

�6

1010

3

(GeV)νE

−10

ICECUBE

Afterglow

Burst

10−8

−910

910

81010

510

610 10

74

WB Limit

Atmospheric

10

−710

−6

pp

pγ (head)

(shocks)γp

(shocks)pp pγ (head)

10 bursts/yr5

He H

E(G

eV

cm

s

s

r

)ν

ε op

−1−1

−2−1

2ν

Φ

(stellar)

• Jet propagating through progenitor,BEFORE emerging from stellar envelope,

can have int. shocks which accel. p+ →pg on unobserved X-rays , → p±, npp, pn on stellar envelope → p±, n

~ few TeV neutrino precursor• If progenitor has Rø~1012 cm (BSG) →

Rate( nm , TeV ) prec > Rate( nm , 100 TeV )int.shock( easier to detect in ICECUBE )

• but, if WR, Rø~1011 cm →Rate( nm , TeV) prec < Rate( nm , 100 TeV ) int.shock→ test progen. size (e.g. @ high z : popIII?)

• At jet break-out: → photon flashes (Ramirez-Ruiz, McFadyen, Lazzati 02; Waxman, Mészáros 02)

i ) thermal keV g flashii) non-therm.10-100 MeV g ( IC upscatt of XR)→ precursors (d few sec.) of “usual” MeV g

• (3) ò Blue n- spectrum: t100 TeVp,g→n from shocks outside star

Meszaros , Waxman 01 PRL 17 1102

Razzaque, PM, EW 03 PRD 68, 3OO1)

WR

H

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GRB 030329: SN shell & precursor with ICECUBE

Burst of Lg~1051 erg/s, ESN ~1052.5 erg, @ z~0.17, q~68o

Prob.of n interaction

4 5 6 7 8 9 10 11

�5

�4

�3

�2

�1

log10[ / GeV]Eν

EΦ

2ν

νlo

g1

0[

/

(Ge

V c

m

s

)

]−

1−

2

Supranova

1 d

−flux from GRB 030329ν

Precursor I

Precursor II

0.1 d

Afterglow (wind)Burst

8 dAfterglow (ISM)

Flux of n

Razzaque, Mészáros, Waxman 03 PRD 69, 23001

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Diffuse UHE n from pop.III collapse

• At z~5-30(?) pop.III ,M~ 30-300 MŸ , Eiso~1054-1056(?) erg

• Buried jets→pg→nm , → n-bursts,

AMANDA/ICECUBE

• “low-z” GRB, AGN etc too

• Detect highest z øform’n,get primordial IMF,

Schneider, Guetta, Ferrara aph/0201342

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ICECUBE:km3

• Extension of Amanda0.15 km3 → km3=1Gton

• Initial funding approved √• 80 strings , 4800 PMTs (ice)

+ air shower surface array • Design for det.all flavor n’s ,

from 107 eV (SN) to 1020 eV

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ôAntares•French/Italian/UK….collaboration•Site off Toulon• Also: NESTOR xGreek/German/Russian…

• Km3 water Cherenkov detector• Deployment approx. 2010• Complement ICECUBE: lsc,abs~(100,10) H20, lsc,abs~(20,100) Ice• Northern site: at lower E complementary sky coverage

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Diffuse UHE n : CR bound and sensitivity, bckg

Mészáros, Heid 04

CR Protons fromGRB

• Internal & extern.(rev) shocks NR Fermi acc. →spectrum N(E)∂E-2

• Can reach E~1020 eV(for xBxe“0.02, G“130)

• CR energy input at1020eVdE/dtdV~1044zerg/Mpc3/yrwhere z~0.5-3 (z-evol.)

• Entire >1020eV CR flux from GRB? yes/no/possib

(Waxman NucPhS 87:345’00; Stecker APPh 14:207 ’00)

1018

1019

1020

1016

1017

E [eV]

J× E

2.61

[eV

1.61

/m2 s

r s]

GRB flux

GRB flux + Fly’s Eye

Galactic (heavy) component

AGASA

Fly’s Eye

Yakutsk

(Waxman, Neutrino 2000, hep-ph/0009152)

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UHECR total power in GRB?• Previous (1995-00): Eg~1051 erg, R(z=0)~30/Gpc3/yr,

dE/dtdV~0.3x1044 erg/Mpc3/yr• New (>2000): Eg~2.5x1053 erg (isot.equiv);

R (z=0) ~5x10-10 /Mpc3/yr, dE/dtdV~1.3x1044 z erg/Mpc3/yr . (z ~ 3-8 to z~1, evol)

Jets: 4p/500 (Eg ∞, RÆ, √ )• → Ee

2 dneGRB/dEe dt ~1044 z erg/Mpc3/yr

• UHECR exg obs: dEpCR/dt ~ 3x1044 erg/Mpc3/yr

→ Ep2 dnp

CR/dEpdt ~0.7x1044 erg/Mpc3/yr, √, OK.(Waxman, astro-ph/0210638)

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UHE Cosmic Rays

• d (t?) 1020 eV (GZK) energy (~4 cal ~ 17 J, ~fast base/cricketball)

• Slam into upper Earth atmosphere →electromagn. shower of secondary particles

• Detect fluoresc. light,Cherenkov light, ioniz/excit/charge

• Origin: GRB, AGN, SN..?

Mészáros, Heid 04

Pierre AugerUltra-high energy cosmic

ray observatory

• NSF & international, South station: (Argentina) partly complete – North: planned• Planned area 3,000 km2 , sensitive to CR energies >1020 eV (GZK lim)• GRB: expect Ep,max~ 1020 eV from Fermi accel. in same shocks where e,B →g• 1600 ground detectors, 11 kliters ea., 1.5 km apart + 4 air fluoresc. telescope • current: 22ö ground det. (35O sq. km) & 2 air fluoresc. tel. installed, Mar O4• Also: tau-nu (horiz.l shower capability: Earth-skimming & through Andes)

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Summary & Prospects• GRB, XXR, XRF may form a continuum; jet geometry

unknown, but unlikely to be very narrow• Polarization (O, g?) will provide important clues• X-ray lines may serve as very high z (d15) distance gauge• GRB continuum (if present) detectable to z d30• UHE g,n will test proton/MHD content of jets, shock

accel.physics, magnetic field generation, turbulence• Probe hadron/EM interactions at t TeV-PeV energies• Investigate stellar evolution & death, star formation rates

and large scale structure at redshifts of first objects• Test strong field gravity, ultrahigh mass/energy densities