Presentation on theme: "Cosmological Magnetic Fields"— Presentation transcript:
1 Cosmological Magnetic Fields 3/28/2017Angela V. OlintoUniversity of Chicago
2 Cosmological Fields?Were there Magnetic Fields before recombination?
3 Cosmological Fields? Were there Magnetic Fields before recombination? If yes:how were primordial Magnetic fields created?What role have they played since?
4 Cosmological Fields? Were there Magnetic Fields before recombination? If yes:how were primordial Magnetic fields created? PHASE TRANSITIONSWhat role have they played since?Star FormationSeed DynamosStructure Formation…
5 Cosmological Fields? Were there Magnetic Fields before recombination? How would we know?Were there Magnetic Fields before galaxies formed?Lyman- forest - intermediate scalesAre there large scale Magnetic Fields today?
6 Extra Galactic Magnetic Fields Constraints from Faraday Rotation to distant Quasars in an Inhomogeneous Universe (Burles, Blasi, A.O. ‘98)variance increases - non-gaussian tailMedian| from z = 0 to 2.5, bh2 = 0.02BHubble 10-9 G (Ly- forest)BHubble G (homogeneous)B50Mpc G (Ly- forest)B50Mpc G (homogeneous)BJ 10-8 G (Ly- forest)BJ G (homogeneous)
7 Cosmological Fields? Where there Magnetic Fields before recombination? How would we know?Were there Magnetic Fields before galaxies formed?Lyman- forest - intermediate scalesAre there large scale Magnetic Fields today?
8 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 dynamicsWhat about in emptier regions?
9 EHE Cosmic Rays should point! 1kpcRgyro = 0.11 Mpc E20/ZBGpBB<10 nGR>11 Mpcafter S. Swordy
10 EHE Cosmic Rays should point! Magnetic Fields less effective at EHEs (~ 1020 eV):Simulations CDM LSS + MFs BExtraGal ~ <10 nG D. Grasso (ICRC03)AGASA clusters constraints BgalG. Medina-Tanco (ICRC03)Isola, Lemoine, Sigl ‘02
11 AGASA Akeno Giant Air Shower Array Presented 3 oral + 2 posters:11 Super-GZK eventsSmall Scale ClusteringConstraints on Composition- protons at UHEs.111 scintillators + 27 muon det.
12 Composition: K. Shinozaki et al. ICRC03 AGASAComposition: K. Shinozaki et al. ICRC03Muon density E0 ≥1019eV q≤36ºFe frac. CL): < 35% (1019 – eV), < 76% (E>1019.5eV)Akeno 1km2 : Hayashida et al. ’95Haverah Park: Ave et al. ’03Volcano Ranch: Dova et al. ICRC03HiRes: Archbold et al. ICRC03AGASAGamma-ray fraction upper limits34% (>1019eV) (g/p<0.45)56% (>1019.5eV) (g/p<1.27)
13 Small Scale Clustering M. Teshima et al. ICRC03 AGASASmall Scale Clustering M. Teshima et al. ICRC031 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 5x1019eVAbove GZK energy (5x1019eV) statistics too smallNo significant time self-correlation
21 systematic errors in by hand… 30% in order to reconcile low energy data ( eV)15% within limits allowed by both collaborationsAGASA -15%HiRes +15%DDM, Blasi, Olinto 2003DDM, Blasi, Olinto 2003best fit slope: 2.6number of events above 1020eV:no 1.5 sigmanumber of events above 1020eV:GZK cutoffDeMarco et al (ICRC03)
22 Composition: J. Mathews et al. ICRC03 HiResComposition: J. Mathews et al. ICRC03HiRes Stereo: unchanging, light composition above 1018 eVStereo HiRes and HiRes Prototype-MIA consistent in overlap regionHiRes Prototype-MIA Hybridchanging composition(Heavy to Light)between 1017 and 1018 eVNo significant informationnear GZK region yetCome back to 29th ICRC
23 GZK cut-off is model and B dependent… Magnetized LocalSuper-Cluster -better fit to spectrum(Blasi, A.O. ‘99)E. Parizot et al. ICRC03
24 Are the sources Astrophysical or New Physics? Pulsar,AGNBL Lacs -some correlationCosmic StringsSuper HeavyDark Matter Relicsin the Dark Haloof our Galaxy
25 Anisostropic UHECRs -BL-Lacs correlation Accounting for deflection by Galactic MF correlation improvesfor charged +1 particles Tinyakov and Tkachev ’01b, 02
27 Auger & EUSO EUSO Auger South DeMarco et al (ICRC03) DDM, Blasi, Olinto 2003DeMarco et al (ICRC03)
28 Pierre Auger Project 2 Giant AirShower Arrays South – Argentina Funded North – Not Funded Yet1600 particle detectors over3000 km2+ 4 Fluorescence DetectorsWill Measure Direction,Energy, & Composition of~ 60 events/yr E > 1020eV~ 6000 events/yr E > 1019eV> 250 scientists from 19 countriesJ. Cronin and T. Yamamoto
36 Statistics improve by 2 Overlap region (purple) L L/ 2 Auger N and S can measure Large Scale Structure + Small Scale ClusteringNumber of sources ~ 2(blue or red)N 2 x NStatistics improve by 2Overlap region (purple)L L/ 2R 21/4 x RN 23/4 x NP. Sommers ‘03
37 The local supercluster (LSC) 3/28/2017The local supercluster (LSC)
40 MAP OF DEFLECTIONS around “Virgo” cluster 3/28/2017MAP OF DEFLECTIONS around “Virgo” cluster
41 Preliminary resultsDolag, Grasso et al 03Significant deflections are obtained only when UHECRs cross a rich cluster of galaxies at a distance < few Mpc’sIn the filaments, where deflections in filaments are neglibibleMF strength around the local group isUHECRs are not isotropized !!
42 ConcludingUHECRs can map Magnetic Fields in Intergalactic Medium ( B ~ nG) and the Galaxy (polarization).Need complete simulations +Better UHECR dataWatch for Auger S + N
43 MSPH simulations of MFs in rich clusters Dolag, Bartelmann & Lesch, ‘99, ‘02MSPH (Magnetic-SPH) simulations implement the SPH (Smoothed Particle Hydrodynamics) strategy by adding MHD equations (Faraday equation) SPH:N-BOBY SIMULATIONS of DM + GAS + MAGNETIC FIELDSInitial conditions ( z ~ 20) : density fluctuation field compatible with -CDM + seed magnetic fieldMAGNETIC FIELD AMPLIFICATION:(frozen-in field)+ non-linear MHD amplification due to the presence of shocks and turbulence
44 They succeed to reproduce observations if 3/28/2017Predictions for -CDMRMsB(R)Dolag, Baterlmann & Lesch ’02They succeed to reproduce observations ifThe memory of the initial MF geometrical structure is lost
45 are below experimental sensitivity if Deflections induced by the smooth component of the cosmic MF:are below experimental sensitivity ifThis 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 thelocal universeIt is consistent with hints of anisotropies in the UHECRs – BL-Lacs correlation
46 Need simulations of EGMF in the LSC ? Close clusters and filaments have the largest cross section.Constrained simulations of EGMF in the LSCA realistic map of deflectionsin order to be able to trace UHECRs back to the sourcethe EGMF in our surroundingsdeflections may differ considerably depending whether we leaveor not in an extended magnetized bubble
47 Constrained MSPH simulation of the LSC 3/28/2017Constrained MSPH simulation of the LSCThe goal is to produce a realistic map of MF in the LSCInitial conditions on density fluctuations are constrained so that thesimulated smoothed density field is equal to that inferred from observationsKolatt ’96Mathis et al. ‘01dark matter only( IRAS survey)
48 3/28/2017ConclusionsMSPH simulations account for observed EGMF in rich clusters without requiring a strong smooth component in the IGMThe “maximal” EGMF compatible with observations give rise to significant UHECR deflections only when they cross or skim clusterized regionsThis is consistent with the claimed UHECR-BL Lacs correlationMSPH constrained simulations will provide soon maps of UHECR deflections to be compared with data from high statistics experimentsthey will allow a more reliable source identificationprovide a deeper insight on the nature of cosmological magnetic fieldsPreliminary results suggest thatUHECR astronomy may be possible
49 The BL-Lacs – UHECR Connection 3/28/2017The BL-Lacs – UHECR ConnectionTinyakov & Tkachev ’01aSmall angle clustering:Very likely, sources of UHECR are pointlike !● Correlation with -ray-loud BL-Lacs:Accounting for deflection by MF in the Galaxy correlation improvesfor charged +1 particles Tinyakov and Tkachev ’01b
50 Implications for the EGMF 3/28/2017Implications for the EGMFAGASA angular resolution : 2.5 degd(z = 0.082) = 351 (70/h) MpcE = 4.09 E 19 eVSee also Berezinsky, Gazizov and Grigoreva ’02Blasi & De Marco, ‘03Tinyakov & Tkachev ’01c
51 simulations with point sources AGASA multipletssimulations with point sourcesB=0 resol.=2.5º g=2.6 m=0E > eV - 57 events10-5 Mpc-3Blasi, DDM 2003, AP in pressAUGER multiplets E > 1020 eV - 70 events in 5 yrsEUSO multiplets E > 1020 eV events in 3 yrs10-5 sources/Mpc3from AGASA Small Scale Anisotropy w/ large uncertainties.Auger & EUSO will greatly reduce the uncertainties.DeMarco et al (ICRC03)
52 Small Scale Clustering - Monocular J. Belz et al. ICRC03 HiResSmall Scale Clustering - Monocular J. Belz et al. ICRC03No significant clustering seen yet.“Bananas are harder than circles…”Flux upper limits of on point sourceswith E > eV Cygnus X-3Dipole limit: Gal. Center, Centaurus A, M-87HiRes-I Monocular Data, E > eVHiRes-I Monocular Data, E > eVUpper limit of 4 doublets (90% c.l.)in HiRes-I monocular dataset.
53 Two-point correlation for HiRes Stereo Events > 1019 eV Small Scale Clustering - Stereo C. Finley et al. ICRC03No significant clustering seen yet.RMS fluctuationsTwo-point correlation for HiRes Stereo Events > 1019 eV
54 Extra Galactic Magnetic Fields UHE CR + Gamma Rays Secondary Photon spectrum modified by EGMFs via synchrotron losses of e+e- in EM cascade (Lee, A.O., Sigl ‘95)BEG ~ G
55 Extra Galactic Magnetic Fields & UHECRs Monte Carlo for Propagation with EGMF Time Delay, Deflection Angle(Lemoine, A.O., Sigl, Schramm’97, Sigl, Lemoine, A.O.’97)E ~ 20 yr (D/10Mpc)2 (E/10EeV)-2 (B/10-11 G)2 (lc/1 Mpc)E ~ 0.02o (D/10Mpc)-1/2 (E/1yr)1/2Need 10 events/clusterAuger
56 Most Recent ExposuresThanks to HiRes and AGASA Collaborations
57 Too Low Statistics for clear GZK or no-GZK determination Emax= eVHiResAGASADDM, Blasi, Olinto 2003, AP in pressDDM, Blasi, Olinto 2003, AP in pressnumber of events above 1020eV:no 2.5 sigmanumber of events above 1020eV:GZK cutoffDeMarco et al (ICRC03)
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