Cosmological Magnetic Fields Angela V. Olinto University of Chicago
Cosmological Fields? • Were there Magnetic Fields before recombination?
Cosmological Fields? • Were there Magnetic Fields before recombination? • If yes: • how were primordial Magnetic fields created? • What role have they played since?
Cosmological Fields? • Were there Magnetic Fields before recombination? • If yes: • how were primordial Magnetic fields created? PHASE TRANSITIONS • What role have they played since? • Star Formation • Seed Dynamos • Structure Formation…
Cosmological Fields? • Were there Magnetic Fields before recombination? • How would we know? • Were there Magnetic Fields before galaxies formed? • Lyman- forest - intermediate scales • Are there large scale Magnetic Fields today?
Extra Galactic Magnetic Fields Constraints from Faraday Rotation to distant Quasars in an Inhomogeneous Universe (Burles, Blasi, A.O. ‘98) variance increases - non-gaussian tail Median| from z = 0 to 2.5, bh2 = 0.02 BHubble 10-9 G (Ly- forest) BHubble 2 10-8 G (homogeneous) B50Mpc 6 10-9 G (Ly- forest) B50Mpc 10-7 G (homogeneous) BJ 10-8 G (Ly- forest) BJ 10-6 G (homogeneous)
Cosmological Fields? • Where there Magnetic Fields before recombination? • How would we know? • Were there Magnetic Fields before galaxies formed? • Lyman- forest - intermediate scales • Are there large scale Magnetic Fields today?
Cosmological Fields? • Were there Magnetic Fields before recombination? • How would we know? • Are there large scale Magnetic Fields today? • Yes - in clusters of galaxies (M ~ 1015 Msolar ) • B can reach 10-6 Gauss (Kronberg et al) • equi-partition with gas dynamics • What about in emptier regions?
EHE Cosmic Rays should point! 1kpc Rgyro = 0.11 Mpc E20/ZBG p B B<10 nG R>11 Mpc after S. Swordy
Magnetic Fields less effective at EHEs (~ 1020 eV): Simulations CDM LSS + MFs BExtraGal ~ <10 nG D. Grasso (ICRC03) AGASA clustersconstraints Bgal G. Medina-Tanco (ICRC03) EHE Cosmic Rays should point! Isola, Lemoine, Sigl ‘02
AGASAAkeno Giant Air Shower Array Presented 3 oral + 2 posters: 11 Super-GZK events Small Scale Clustering Constraints on Composition - protons at UHEs. 111 scintillators + 27 muon det.
AGASA Composition: K. Shinozaki et al. ICRC03 • Muon density E0 ≥1019eV q≤36º • Fe frac. (@90% CL):< 35% (1019–1019.5eV), < 76% (E>1019.5eV) • Akeno 1km2 : Hayashida et al. ’95 • Haverah Park: Ave et al. ’03 • Volcano Ranch: Dova et al. ICRC03 • HiRes: Archbold et al. ICRC03 AGASA Gamma-ray fraction upper limits (@90%CL) 34% (>1019eV)(g/p<0.45) 56% (>1019.5eV)(g/p<1.27)
AGASA Small Scale ClusteringM. Teshima et al. ICRC03 • 1 triplet + 6 doublets (2 triplets + 6 doublets with looser cut) • Clustering for E ~1019eV and ~5x1019eV, • Ratio of Cluster/All increases with E up to 5x1019eV • Above GZK energy (5x1019eV) statistics too small • No significant time self-correlation
Angular Correlations Log E>19.0 Log E>19.2 Log E>19.4 Log E>19.6
2D-Correlation Map in (ΔlII ,ΔbII ) Log E >19.0eV, 3. 4σ Log E >19.2eV, 3. 0σ Polarization studies will limit B gal and B Xgal ΔbII ΔlII Log E >19.4eV, 2.0σ Log E >19.6eV, 4.4σ
Energy spectrum of Cluster eventsE -1.8±0.5 Cluster Component
AGASA 11 events with E > 1020 eV M. Takeda et al. ICRC03 AGASA systematic errors ~ 18% Flux * E3
The High Resolution Fly’s Eye (HiRes) Pioneers of Fluorescence Technique (8 oral + 4 posters) No Super-GZK flux No Small Scale Clustering Composition Change • Air fluorescence detectors • HiRes 1 - 21 mirrors • HiRes 2 - 42 mirrors • Dugway (Utah) • start ‘97HR1 ‘99HR2 HiRes 1 HiRes 2
Systematic off-set Thanks to D. Bergman
30% in order to reconcile low energy data (1018.5-1019.5 eV) • 15% within limits allowed by both collaborations systematic errorsin by hand… HiRes +15% AGASA -15% DDM, Blasi, Olinto 2003 DDM, Blasi, Olinto 2003 best fit slope: 2.6 number of events above 1020eV: no GZK @ 1.5 sigma number of events above 1020eV: GZK cutoff DeMarco et al (ICRC03)
HiRes Composition: J. Mathews et al. ICRC03 • HiRes Stereo: unchanging, light composition above 1018 eV • Stereo HiRes and HiRes Prototype-MIA consistent in overlap region • HiRes Prototype-MIA Hybrid • changing composition • (Heavy to Light) • between 1017 and 1018 eV • No significant information • near GZK region yet • Come back to 29th ICRC
GZK cut-off is model and B dependent… Magnetized Local Super-Cluster - better fit to spectrum (Blasi, A.O. ‘99) E. Parizot et al. ICRC03
Are the sources Astrophysical or New Physics? Pulsar, AGN BL Lacs - some correlation Cosmic Strings Super Heavy Dark Matter Relics in the Dark Halo of our Galaxy
Anisostropic UHECRs -BL-Lacs correlation Accounting for deflection by Galactic MF correlation improves for charged +1 particlesTinyakov and Tkachev ’01b, 02
Auger & EUSO EUSO Auger South DDM, Blasi, Olinto 2003 DeMarco et al (ICRC03)
Pierre Auger Project • 2 Giant AirShower Arrays • South – Argentina Funded • North – Not Funded Yet • 1600 particle detectors over • 3000 km2 • + 4 Fluorescence Detectors • Will Measure Direction, • Energy, & Composition of • ~ 60 events/yr E > 1020eV • ~ 6000 events/yr E > 1019eV > 250 scientists from 19 countries J. Cronin and T. Yamamoto
Pierre Auger Project 3000 km2 - 1600 water tank array
Auger South 130 tanks on +40 EA
Fluorescence Telescopes • Complete Calibration from Atmosphere to Telescope • LASERS • LIDARS • Telescope and Mirrors Calibs…
top view in shower plane Inclined showers Great Resource for Asymmetry of Showers M. T. Dova et al ICRC03 which lead to novel Composition Studies M. Ave et al ICRC03
Matter and Galaxies N - Super Galactic Plane S - see through Galactic Center A. Kravtsov
Matter Distribution A. Kravtsov
Auger N and S can measure Large Scale Structure +Small Scale Clustering Number of sources ~ 2 (blue or red) N 2 x N Statistics improve by 2 Overlap region (purple) L L/ 2 R 21/4 x R N 23/4 x N P. Sommers ‘03
Gas + DM Kravtsov, Klypin & Hoffman ‘01
Sigl, Miniati & Enßlin, ‘03 UHECRs isotropization (?) observer position
Preliminary results Dolag, Grasso et al 03 • Significant deflections are obtained only when UHECRs cross a rich cluster of galaxies at a distance < few Mpc’s • In the filaments, where • deflections in filaments are neglibible • MF strength around the local group is • UHECRs are not isotropized !!
Concluding • UHECRs can map Magnetic Fields in Intergalactic Medium ( B ~ 1 - 10 nG) and the Galaxy (polarization). • Need complete simulations + • Better UHECR data • Watch for Auger S + N
MSPH simulations of MFs in rich clusters Dolag, Bartelmann & Lesch, ‘99, ‘02 • MSPH (Magnetic-SPH)simulations implement the SPH (Smoothed Particle Hydrodynamics) strategy by adding MHD equations (Faraday equation) SPH: • N-BOBY SIMULATIONS of DM + GAS + MAGNETIC FIELDS • Initial conditions ( z ~ 20) : density fluctuation field compatible with -CDM + seed magnetic field • MAGNETIC FIELD AMPLIFICATION: • (frozen-in field) • + non-linear MHD amplification due to the presence of shocks and turbulence
Predictions for -CDM RMs B(R) Dolag, Baterlmann & Lesch ’02 They succeed to reproduce observations if The memory of the initial MF geometrical structure is lost
Deflections induced by the smooth component of the cosmic MF: are below experimental sensitivity if This is consistent with the UHECRs – BL-Lacs correlation ! Probability to cross a rich cluster outside the LSC for a CR coming from d < 1000 Mpc: Deflections have to be dominated by EGMF in the local universe It is consistent with hints of anisotropies in the UHECRs – BL-Lacs correlation
Constrained MSPH simulation of the LSC Initial conditions on density fluctuations are constrained so that the simulated smoothed density field is equal to that inferred from observations • The goal is to produce a realistic map of MF in the LSC Kolatt ’96 Mathis et al. ‘01 dark matter only ( IRAS survey)
Conclusions • MSPH simulations account for observed EGMF in rich clusters without requiring a strong smooth component in the IGM • The “maximal” EGMF compatible with observations give rise to significant UHECR deflections only when they cross or skim clusterized regions • This is consistent with the claimed UHECR-BL Lacs correlation • MSPH constrained simulations will provide soon maps of UHECR deflections to be compared with data from high statistics experiments • they will allow a more reliable source identification • provide a deeper insight on the nature of cosmological magnetic fields • Preliminary results suggest that • UHECR astronomy may be possible
The BL-Lacs – UHECR Connection Tinyakov & Tkachev ’01a • Small angle clustering: • Very likely, sources of UHECR are pointlike ! • ● Correlation with -ray-loud BL-Lacs: Accounting for deflection by MF in the Galaxy correlation improves for charged +1 particlesTinyakov and Tkachev ’01b
Implications for the EGMF • AGASA angular resolution : 2.5 deg • d(z = 0.082) = 351 (70/h) Mpc • E = 4.09 E 19 eV See also Berezinsky, Gazizov and Grigoreva ’02 Blasi & De Marco, ‘03 Tinyakov & Tkachev ’01c
AGASA multiplets simulations withpoint sources B=0 resol.=2.5º g=2.6 m=0 E > 4 1019 eV - 57 events 10-5 Mpc-3 Blasi, DDM 2003, AP in press AUGER multiplets E > 1020 eV - 70 events in 5 yrs EUSO multiplets E > 1020 eV - 180-360 events in 3 yrs 10-5 sources/Mpc3 from AGASA Small Scale Anisotropy w/ large uncertainties. Auger & EUSO will greatly reduce the uncertainties. DeMarco et al (ICRC03)
HiRes Small Scale Clustering - Monocular J. Belz et al. ICRC03 • No significant clustering seen yet. • “Bananas are harder than circles…” • Flux upper limits of on point sources • with E > 1018.5 eV Cygnus X-3 • Dipole limit: Gal. Center, Centaurus A, M-87 HiRes-I Monocular Data, E > 1019.5 eV HiRes-I Monocular Data, E > 1018.5 eV Upper limit of 4 doublets (90% c.l.) in HiRes-I monocular dataset.