High energy astronomy and Gamma-ray bursts Eli Waxman Weizmann Institute, ISRAEL

Outline The origin of UHECRs (>10 19 eV): Unknown Part I: UHECR-GRBs Part II: The role of astronomy

What do we know about >10 19 eV CRs? J(>10 11 GeV)~1 / 100 km 2 year 2  sr Most likely X-Galactic (R L =  /eB=40  p,20 kpc) Composition? HiRes- p, Auger- becoming heavier? (Uncertain  pp ) (An)isotropy: 2 , consistent with LSS Production rate & spectrum: protons,  2 (dQ/d  ) ~ erg/Mpc 3 yr + GZK Acceleration (expanding flow): Confinement  L>L B >10 12 (  2 /  ) (  /Z eV) 2 L sun Synch. losses   > (L 52 ) 1/10 (  t/10ms) -1/5 !! No L>10 12 L sun at d<d GZK  Transient Sources [EW 95]

UHECR sources: Suspects Constraints: - L>10 12 (  2 /  ) L sun -  2 (dQ/d  ) ~ erg/Mpc 3 yr - d(10 20 eV)<d GZK ~100Mpc !! No L>10 12 L sun at d<d GZK  Transient Sources Gamma-ray Bursts (GRBs)  L  ~ L Sun >10 12 (  2 /  ) L sun = (  / ) 2 L sun   ~ (L 52 ) 1/10 (  t/10ms) -1/5  2 (dQ/d  )  ~ erg* /Mpc 3 yr = erg/Mpc 3 yr Transient:  T  ~10s <<  T p  ~10 5 yr Active Galactic Nuclei (AGN, Steady):  ~ 10 1  L>10 14 L Sun = few brightest !! Non at d<d GZK  Invoke: * “ Dark ” (proton only) AGN * L~ L Sun,  t~1month flares (from stellar disruptions) [Blandford 76; Lovelace 76] [EW 95, Vietri 95, Milgrom & Usov 95] [EW 95] [Boldt & Loewenstein 00] [Farrar & Gruzinov 08]

UHECR per GRB Uncertainties: Absolute E CR calibration E CR /E UHECR z=0 high-L GRB rate [Guetta et al. 2010]

GRB int./ext. shock acceleration Confinement  L>L B >10 12 (  2 /  ) (  /Z eV) 2 L sun L B ~L  ?? Internal shocks (  ~1): B~B equip, L B ~L Does not necessarily require orders of magnitude amplification

GRB int./ext. shock acceleration External (  >>1): B up ~10 -5 B equip ?? L B <<L, No UHE acceleration?? e - t(acceleration) < t(IC) X-ray AG  B > 0.2 n 0 5/8 mG >> 1  G 100MeV  B > 5 n 0 5/8 mG (0.1mG )  Upstream field generation, Possible external Consistent with theoretical considerations (Kumar & Barniol-Duran 09: No amplification? Parameter fit {  B,  e … } ignoring physics)  p Shock frame Downstream Upstream [Li & EW 06] [Li 10] [Piran &Nakar 10] [eg Keshet et al 09; Nishikawa et al. 09]

HE  Astronomy p +   N +   0  2  ;  +  e + + e +  +   Identify UHECR sources Study BH accretion/acceleration physics E 2 dQ/dE=10 44 erg/Mpc 3 yr &   p <1: If X-G p ’ s:  Identify primaries, determine f(z) [EW & Bahcall 99; Bahcall & EW 01] [Berezinsky & Zatsepin 69]

HE experiments Optical Cerenkov - South Pole Amanda: 660 OM, 0.05 km 3 IceCube: +660/yr OM (05/06 … ) 4800 OM=1 km 3 s - Mediterranean Antares: 10 lines (Nov 07), 750 OM  0.05 km 3 Nestor: (?)  0.1 km 3 km3Net: R&D  1 km 3 UHE: Radio Air shower Aura, Ariana (in Ice) Auger (  ) ANITA (Balloon) EUSO (?) LOFAR

GRB ’ s If: Baryonic jet Background free: [EW & Bahcall 97, 99; Rachen & Meszaros 98; Guetta et al. 01; Murase & Nagataki 06]

GRB  & f p  Prompt ~1MeV synch  f p  ~   (100MeV)~1   (100MeV)~1  ~300 Prompt GeV photons    (100MeV) >300, no ’ s ?? Is   (100MeV)<<1? Challenge to prompt MeV sync production 95% of LGRB not detected by LAT For bright GRBs, non detection implies: F(>100MeV)/F(1MeV) ~1 ? [Abdo et al. 09; Greiner et al. 09; Dermer 10] [Guetta et al. 10]

GRB  ’ s Caution in inferring  min : - No exponential cutoff at   >1, rather f ~1/ - GeV & MeV emission likely originate from different radii (HE delay), (   =1)~R Internal collisions at R 0  “ residual ” R>> R 0 E(R)~1/R q with q<2/3 f ~1/ q for > (   =1,R= R 0 ) May account for: prompt optical (avoid self-abs.) prompt GeV (avoid pair prod.) GRB080916c HE delays   ~300 [Li & EW 08] [Li 10]

The current limit [Achterberg et al. 08 (The IceCube collaboration)]

TeV GRB ’ s Collapsar jet penetration, failed SN jet : TeV ’ s [Meszaros & EW 01; Razzaque et al. 03, 04; Guetta & Granot 03; Dermer & Atoyan 03 Ando & Beacom 05]

- physics & astro-physics  decay  e :  :  = 1:2:0 (Osc.)  e :  :  = 1:1:1  appearance experiment GRBs: -  timing (10s over Hubble distance) LI to 1:10 16 ; WEP to 1:10 6 EM energy loss of  ’ s (and  ’ s)  e :  :  = 1:1:1 (E>E 0 )  1:2:2  GRBs: E 0 ~10 15 eV Combining E E 0 flavor measurements may constrain CPV [Sin  13 Cos  ] [EW& Bahcall 97] [Rachen & Meszaros 98; Kashti & EW 05] [EW & Bahcall 97; Amelino-Camelia,et al.98; Coleman &.Glashow 99; Jacob & Piran 07] [Blum, Nir & EW 05]

Summary UHECRs Origin- an outstanding puzzle GRBs- only known sources satisfying all constraints astronomy Detectors approach required ~1Gton scale Resolve UHECR puzzle: composition, sources Resolve GRB physics open Q: Baryonic/Poynting jet, , particle acceleration [test collapsar jets, X/FUV flares] Constrain physics, LI, WEP

Composition clues HiRes 2005 Auger 2009 Protons Heavier at highest E? Or: modified  extrapolation? (s~300 TeV) [E.g. Wibig 08,09; Ulrich et al. 09 Kusenko 10]

[EW 1995; Bahcall & EW 03] [Katz & EW 09] protons, dQ/dE~(1+z) m E -  t eff. : p +  CMB  N +  Q=J/ t eff. Consistent with protons, E 2 (dQ/dE) ~ erg/Mpc 3 yr + GZK Production rate & Spectrum ct eff [Mpc] GZK (CMB) suppression log(E 2 dQ/dE) [erg/Mpc 2 yr]

Back up slides

Anisotropy 98% CL; Consistent with LSS (Correlation with low-luminosity AGN? Trace LSS) Anisotropy/Compostion connection Acceleration of Z(>>1) to E  Acceleration of p to E/Z Anisotropy of E  Stronger E/Z Anisotropy not E/Z  E~ eV Biased (  source ~  gal for  gal >  gal ) [Kashti & Waxman 08] [:Lemoine & EW 09]

AMANDA & IceCube

The Mediterranean effort ANTARES (NESTOR, NEMO)  KM3NeT

Mark Westmoquette (University College London), Jay Gallagher (University of Wisconsin-Madison), Linda Smith (University College London), WIYN//NSF, NASA/ESA Robert Gendler M82 M81

A lower bound: Star bursts Star burst galaxies: - Star Formation Rate ~10 3 M sun /yr >> 1 M sun /yr “ normal ” (MW) - Density ~10 3 /cc >> 1/cc “ normal ” - B ~1 mG >> 1  G “ normal ” Most stars formed in (z>1.5) star bursts High density + B: CR e - ’ s lose all energy to synchrotron radiation CR p ’ s lose all energy to  production [Loeb & Waxman 06] [Quataert et al. 06]

Synchrotron radio  calibration [Loeb & Waxman 06] M82, NGC253: Hess, VERITAS 09 Fermi 09  dN/dE~1/E p, p<~2.2 Starbursts       

The eV challenge R B v v 2R  t RF =R/  c) l =R/   22 22 [Waxman 95, 04, Norman et al. 95]

The GRB “ GZK sphere ” LSS filaments: D~1Mpc, f V ~0.1, n~10 -6 cm -3, T~0.1keV  B =(B 2 /8  nT~0.01 (B~0.01  G), B ~10kpc Prediction: p  D B [Waxman 95; Miralda-Escude & Waxman 96, Waxman 04]

GRB Model Predictions [Miralda-Escude & Waxman 96]

Indirect detection 3,000 km 2 J(>10 11 GeV)~1 / 100 km 2 year 2  sr Ground array Fluorescence detector Auger: 3000 km 2