Shigeru Yoshida and Aya Ishihara Constraints on the origins of the ultra-high energy cosmic-rays using the IceCube diffuse neutrino limits Shigeru Yoshida and Aya Ishihara Department of Physics Chiba University

IceCube is reaching to the GZK regime A.Ishihara for the IceCube collaboration ICRC (2011) ¼ IceCube ½ IceCube 2009 Full IceCube sensitivity (MC)

IceCube is reaching to the GZK regime IceCube collaboration (Corres. A. Ishihara) PRD 83 092003 (2011) Models The half IceCube # of events The full IceCube (3 years) 　GZK1 (Yoshida et al) * 0.57 3.1 　GZK2 Strong Evol. (Sigl) ** 0.91 (C.L 53.4%) 4.9 　GZK3 (ESS with WL=0.0) *** 0.29 1.5 　GZK4 (ESS with WL=0.7) *** 0.47 2.5 　GZK5 (Ahlers max) **** 0.89 (C.L 52.8%) 4.8 　GZK6 (Ahlers best fit) **** 0.43 2.3 　Z-Burst # 1.03 (C.L 55.7%) 5.1 　Top Down(SUSY) ## 5.68 (C.L 99.6%) 31.6 　Top Down(QCD) ### 1.19 (C.L 66.4%) 6.3 　W&B(evol) ^ 3.7 24.5 　W&B(no evol) ^ 1.1 5.5

“GZK” n = history of UHECR radiation Yoshida and Teshima, Prog.Theo.Phys. 83 833 (1993) m=4 In < 1 EeV  source evolution m=2 ~ (1+z)m In > 10 EeV  Emax Emax =1022 eV Emax =1021 eV

In @ 1EeV is robust against Kotera, Allard, Olinto JCAP 10 013 (2010) Emax dependence IceCube Energy Range IceCube collaboration (Corres. A. Ishihara) PRD 83 092003 (2011) Transition model dependence In @ 1EeV is robust against Emax and UHECR transition model

Identify UHECR sources by measurement of cosmological evolution Kotera, Allard, Olinto JCAP 10 013 (2010) Evolution Curve IceCube Energy Range GZK n n @O(1EeV)= early history of cosmic radiation!

GZK cosmogenic n flux estimates: model-independent analytical approach Adding up contribution from sources at z Emission rate per comoving volume ~(1+z)m n yield with EGEN=En(1+zn) from UHECR proton emitted from sources at z>zn. zn; redshift when generates n Semi-analytically computable when neglect IR/O background – n is generated only by pgCMB photo-pion production only via D-resonance simplify the pg collision kinematics as a single pion production approximate UHECR energy attenuation length as a constant above 1020 eV Usable as GZK n version of Waxman-Bahcall Formula

Comparison with the “full-blown” MC IceCube Energy Range Remarkable agreement around En~ 1EeV departure at En<100PeV due to the far-IR contribution and D-resonance approximation departure at En>5EeV Analytical formula due to Emax, E-a dependence Numerical/MC Provides reasonable estimates In the IceCube energy range within uncertainty of ~factor of two uncertain far-IR roles uncertain UHECR flux accuracy of the approx. consistent with

Constraints on UHECR source evolution At present --- a half IceCube 2008-2009 run IceCube collaboration PRD 83 092003 (2011) r ~ (1+z)m 0<z<zmax Already disfavors AGN radio-loud jet as UHECR emitter AGN FR II

Constraints on UHECR source evolution In 3 years --- full IceCube 5 year run r ~ (1+z)m 0<z<zmax IF null detection… Completely rule out AGN radio-loud jet as UHECR emitter AGN FR II

Constraints on UHECR source evolution In 3 years --- full IceCube 5 year run GRB r ~ (1+z)m 0<z<1 IF null detection… r ~ const. 1<z<zmax SFR Disfavors GRB/normal galaxies as UHECR emitter UHECR composition hypothesis (proton dominated) now in question!

Summary and Conclusion GZK n search by IceCube puts solid constraints on UHECR source evolution insensitive to uncertain radio, IR/O BSL and B in contrast to the bound by the Fermi diffuse g limit (ex. Ahlers et al Astropart.Phys. 2010) UHE n detection rate at O(EeV) is a practical indicator of the source evolution realizable by IceCube, ARA, ARIANNA etc. A null detection by IceCube would suggest UHECR sources are very weakly evolved with m<3 or heavy nuclei composition

Backup

GZK cosmogenic n estimates: derivation from the energetics Similar method used in Wang, Liu, Aharonian, ApJ 736 112 (2011) Total energy channeling into n relative to injected p energy (Engel Seckel, Stanev PRD 64 093010 2001) Pros: No D-resonance approximation  better description for low En This method Cons: Significant overestimation of flux for higher En, and consequently, high-Z epochs because it neglects attenuation of UHECR flux by the GZK mechanism