Les Houches 2002 School and Workshop on Neutrino Particle Astrophysics Les Houches, France 21/01-01/02 2002. Auger: a New Window into Ultra High Energy Cosmic Rays Antoine Letessier-Selvon, LPNHE, IN2P3-CNRS, University of Paris VI & VII. Les Houches 2002 A.Letessier-Selvon 1
✁ ✁ ✁ ✁ � � ✁ � ✁ � Contents I UHECR Problematics II EAS characteristics and detection technics. III Auger. IV Photon and Neutrino detection. References : M. Nagano and A. A. Watson, Observation and implication of the ultrahigh-energy cosmic rays, Review of Modern Physics, Vol 72, No 3 (2000) 689. X. Bertou, M. Boratav and ALS, Physics of Extremely High Energy Cosmic Rays, International Journal of Modern Physics A., Vol 15, No 15 (2000) 2181. P .Bhattacharjee and G.Sigl, Origin and Propagation of Extremely High Energy Cosmic Rays, Physics Report Vol. 327 (2000) 109. V. Berezinsky, P .Blasi, A.Vilenkin, Signatures of Topological Defects, Physical Review D58 (1998). Auger Design Report, http://www.auger.org/admin/DesignReport. S.Yoshida and H.Dai, The Extremely High Energy Cosmic Rays, J.Phys. G24 (1998) 905. Les Houches 2002 A.Letessier-Selvon 2
Ultra High Energy Cosmic Rays Les Houches 2002 A.Letessier-Selvon 3
✄ ☎ ✆ ✝ ✡ ✡ ✂ Victor Hess (1912) ✂ Showers of secondary particles : Pierre Auger (1938) ✞✠✟☛✡✌☞✎✍✑✏ Taille ✂ Around 10 ✒ eV : Galactic origin (strong Solar modulation) ✡✌☞ eV : Galactic origin (SNR) ✂ Between 10 ✒ eV and 10 ✡✌☞ eV and 10 ✡✔✓ eV-10 ✂ Between 10 ✒ eV : Yet unclear, galactic. ✂ Above 10 ✒ eV : Unknown but likely extra-galactique. Les Houches 2002 A.Letessier-Selvon 4
Observed spectrum (characteristics) -2.7 dF E CR I dE Knee 100 [Arbitrary Unit] -3.0 dF 10 E dE CR II 2 E Expected Curve for dF dE Extragalactic Origins 1 2nd Knee -3.2 dF E dE Dip Flattening -1 10 CR III Cutoff? -2 10 -3 10 14 15 16 17 18 19 20 21 22 10 10 10 10 10 10 10 10 10 ENERGY [eV] Les Houches 2002 A.Letessier-Selvon 5
✣ ✜ ✜ ✘ ✜ ✘ ✘ ✩ ✜ ✘ ✜ ✕✗✖ Above 10 eV Production mechanisms? How to obtain such a high energy ? Primary nature (Composition) ? Sources distribution ? Where do they come from and how do they reach us ? Where does the spectrum ends ? The very existence of cosmic rays above 10 ✙✔✚ eV is a mystery... which we want to solve. Orders of magnitude ( at 10 ✙✔✚ eV) ✛ Energy : 510 ✙✌✚ eV 10 Joule 2g of lead out of a hunt gun (350 km/h). ✢ Flux : One event per 50 km ✣ and per year detection surface ✤✦✥ 1000km ✢ Density : At ground level 10 ✙✔✧ - 10 ✙★✙ particles, ¿99% EM (10 MeV) ¡1% muons (1GeV) ✢ Size : 20 km ✣ foot print (1 part/m ✣ at 1.5 km from the axis) ✢ Opacity : MFP 10-100Mpc i.e. between 10 ✚ and 10 ✩✫✪ of the Universe (10 Gpc) World record: E = 3 ✬ 10 ✭✯✮ eV 50 Joule (tennis ball above 100 km/h, 100 millions times a LHC beam) Les Houches 2002 A.Letessier-Selvon 6
❫ ❑ ❞ ❞ ✰ ❑ Transport Nucleons: GZK cut-off from pion photo-production on the CMB. ✰✲✱✴✳✶✵✸✷☛✹✻✺✽✼✿✾❁❀❃❂❅❄❇❆❉❈❉❊●❋❁❍✠✾■❈❉❊ ❂◆▼P❖◗❋❁❍✠✾●❘❚❙◗❯❲❱✿❳ ❏▲❑ and Proton energy as a function of source distance. After 100Mpc the final energy falls below ❨✯❩✑❬❪❭ eV Mean energy loss length of protons as recently calcu- lated with a Monte Carlo [Stanev et al]. ✰❡❢❣❂❤✰❡❋ ❫★❴❛❵❝❜✽❜ ✰❡❆ ✰❧❦ ✐❚❥ A comparision with other cal- culations. Les Houches 2002 A.Letessier-Selvon 7
t Consequences on observed spectra : 10 0.004 [Arbitrary Unit] 1 0.008 0.057 -1 10 0.016 0.032 0.1 3 dE E 0.5 dF -2 10 1.0 -3 10 17 18 19 20 21 22 10 10 10 10 10 10 ENERGY [eV] Observed spectra as a function of observed distance from the source (in units of z). The injection spectra is a power law : r✈✉s✇ . ♠✫♥♣♦q♠sr Les Houches 2002 A.Letessier-Selvon 8
Photons : EM cascades. ( Pair production) Threshold on CMB : ①❧②❇③⑤④ ⑥●⑦❅⑧⑩⑨❷❶✯❸❡❹❻❺❽❼❿❾ Targets : CMB photons, infra-red (IR) and, at very high energy, radio (URB). NB: IR and URB are not very well known. 5 proton photopion proton pair 4 red shift limit 3 photon+IR Iron 2 1 photon+radio 0 -1 photon+CMBR -2 -3 10 12 14 16 18 20 22 24 ➀ Top-Down UHECR production models give dominantly photons and neutrinos at the sources. ➀ Gammas, neutrinos (and ❼➂➁❲❼➂➃ ) are also secondary of the pion photo-production. Les Houches 2002 A.Letessier-Selvon 9
➑ ➐ ➌ Magnetic Fields. 1) Affects the development of EM cascades. Dominant above : ➄➆➅✽➇➉➈ ➊✠➋☛➌✌➍➏➎ ➊✠➋➒➑ ➍❽➓→➔ At threshold (dependent upon the URB density) the loss is about ➌✔↕ eV per 100kpc. ➣❲↔ 10 2) Bends and delay charged particles : Left : Bottom :0.5 kpc trajectory in the Galactic disk or (equivalently) 1 Mpc in inter-galactic space. Top : 30 Mpc trajectory in a random field of 1 Mpc coherence length. Right : Time delays computed in the same conditions. Les Houches 2002 A.Letessier-Selvon 10
â ó Ð Ð ñ ➞ ➜ Ð ô ➩ ➱ ➞ ➱ ➮ ➛ ➵ Ü Ó ➳ Ò ➙ ➛ ➡ ➜ ➞ ➡ Ó Ú ➷ Ý Ø ➛ ➫ Õ Þ Ð Production or Acceleration Or how to achieve 10 ➜❪➝ eV? Acceleration (Bottom-Up) “Classic” - Supernova remnants (SNR). Not energetic enough - Radio Galaxies (powerful ones!). Ok but rather far away - Young neutron stars. Hard to escape, loss at the source - GRB. Cosmological distribution Sources far away ( ➤➦➥ ) GZK cut off ➟✠➠●➠➢➡ ➧✻➨ Sources nearby ( ➤✶➥ ) visible. ➟✠➠●➠➢➡ ➧✻➨ Decay (Top-Down) “Exotic” Massive particles or TD are the source of CR (no acceleration) - Topological defects collapses, intersections or interactions (strings, Monopoles, super-conducting strings, vortons...) Fluxes, constraints from CMB isotropy, EGRET measurements of diffuse gamma rays and ➫➯➭⑩➲ abundance. - Massive (M 10 ➜❪➝ eV) (meta) stable relic particles, (e.g. cryptons). DK ( 100Mpc) and flux (@10 ➜❪➝ eV) ➸✗➺➢➻❇➼ ➝❽➽➚➾➆➪➹➶ ➘✯➴❡➷➬➷ Cosmological distribution or DM like? Solve Acceleration, power and invisibility, and are dominant at the source. Mixed : e.g. Kaluza-Klein interactions (Physics (just) beyond SM) - [Nussinov and Shrok (1999), Sigl (2000)] : ✃❲❐❮❒ ❰Ï❰ Ó➉Ô ➫★Ñ➂Ò ➟✠➠➒Õ ➜×ÖÙØ ➥➯á ➲❪ÛÙÜ ➲❪Û❧Ü ➝ßÞ❝à - [Kachelrie and Pl¨ umacher (2000)] : ✃äã❁å❃ã ✃❲❐P❒ ❰Ï❰çæ æ✿ëqì ➝❮íïî★ð➬î ➜■è×é❝ê❲➜ ➜■èÏØ ➟✠➠➒Õ ➜★ò ➥➯á ➜❪➝ eV) and ( ➠s÷ø➟ ) ( ➘ Tev, E= õö➩ ➘✯➴ Les Houches 2002 A.Letessier-Selvon 11
Hillas-plot (candidate sites for E=100 EeV and E=1 ZeV) 15 Neutron star GRB Protons (100 EeV) 9 Protons log(Magnetic field, gauss) (1 ZeV) White 3 AGN dwarf Fe (100 EeV) RG lobes Colliding -3 galaxies Crab x SNR Clusters Galactic disk x halo Virgo -9 3 6 9 12 15 18 21 1 au 1 pc 1 kpc 1 Mpc log(size, km) E ~ ZBL max Les Houches 2002 A.Letessier-Selvon 12
û û û ✢ û ü û ✓ ✕ ✙ ✙ ✕ û ☎ Some Top-down predictions Kalashev, Kuzmin and Semikoz [1999]. 4 γ e p 3 n ν e ν µ 2 log 10 (j(E)E 2 ) (eV cm -2 s -1 sr -1 ) 1 0 -1 -2 -3 -4 -5 10 12 14 16 18 20 22 log 10 (E/eV) ü✯ýÿþ★þ ✁�✄✂ ü✯ý ✝✆✟✞✡✠ ü✯ý ✑✏✎✒ ✌þ ✔✓ ù❷ú ✚✄✚ ) , and ☛✌☞✎✍ . ( ✖✘✗ 3 γ e p 2 n ν e ν µ 1 log 10 (j(E)E 2 ) (eV cm -2 s -1 sr -1 ) 0 -1 -2 -3 -4 -5 -6 10 12 14 16 18 20 22 24 log 10 (E/eV) þ ✜✛ �✄✂ ✏✎✒ ✌þ ù❷ú ü✯ý ü✯ý ✚✣✚ ) , and ☛✌☞✎✍ . ( ✖✘✗ Les Houches 2002 A.Letessier-Selvon 13
✾ ✤ ✤ ✬ ✤ Gamma Ray Burst : Expanding fireball model : [Waxman] Engine? Distribution : very likely cosmological (after glow). High luminosity (energy output) ✥✝✦★✧✪✩ ergs/sec ( ✥✝✦★✧✜✫ ergs). Time delays: cosmological distribution a few local events. At most 1 every 50 years within 100 Mpc. 2 UHECR events (AGASA and FE) within 26 months and with too ✭✯✮ large for a single source EGMF ✰✎✱ ✭✳✲✵✴ ✶✁✷✸✷✣✹★✺✼✻✽✬ ✶✁✷★✿✎❀ ✩❂❁ 1e+26 1e+25 J(E) x E 3 (m -2 sr -1 s -1 eV 2 ) 1e+24 1e+23 1e+22 1e+17 1e+18 1e+19 1e+20 1e+21 Energy (eV) UHECR fluxes from GRB [Scully and Stecker 2000]. 3 redshift dependence of the GRB density: - Solid strong ( ❃❄✰ ❅❇❆❉❈❇❊✪❋✔●■❍❑❏✳✰ ❅❇❆▲❈ ) from [Fenimore and Ramires-Ruiz] - Dashed same as star formation rate ( ❃▼✰ ❅❇❆▲✷❇❊✪❋◆●■❍❑❏✳✰ ❖P❆❘◗ ) - Dotted no redshift dependence The GZK cut-off is always visible. Les Houches 2002 A.Letessier-Selvon 14
Extended Air Showers Les Houches 2002 A.Letessier-Selvon 15
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