Multi-Messenger Astonomy with Cen A?

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1 Multi-Messenger Astonomy with Cen A? Michael Kachelrieß NTNU, Trondheim []

2 Outline of the talk 1 Introduction 2 Dawn of charged particle astronomy? Expectations vs. Auger data Effects of cluster fields 3 Multi-messenger astronomy with Cen A? 4 Conclusions

3 Outline of the talk 1 Introduction 2 Dawn of charged particle astronomy? Expectations vs. Auger data Effects of cluster fields 3 Multi-messenger astronomy with Cen A? 4 Conclusions

4 Outline of the talk 1 Introduction 2 Dawn of charged particle astronomy? Expectations vs. Auger data Effects of cluster fields 3 Multi-messenger astronomy with Cen A? 4 Conclusions

5 Outline of the talk 1 Introduction 2 Dawn of charged particle astronomy? Expectations vs. Auger data Effects of cluster fields 3 Multi-messenger astronomy with Cen A? 4 Conclusions

6 1910: Father Wulf measures ionizing radiation in Paris 80m: flux/2

7 1910: Father Wulf measures ionizing radiation in Paris 300m: flux/2 80m: flux/2

8 What do we know 98 years later? solar modulation LHC

9 What do we know 98 years later? solar modulation only two bits of information? exponent α of dn/de 1/E α chemical composition, uncertain at UHE LHC

10 PAO data: energy spectrum

11 PAO data: energy spectrum )) -1 s -1 sr -1 ev -2 lg(j/(m E (ev) ) J/(AxE Auger HiRes I lg(e/ev)

12 PAO data: energy spectrum )) -1 s -1 sr -1 ev -2 lg(j/(m E (ev) E 1/2 consistent with GZK suppression 1 ) J/(AxE Auger HiRes I lg(e/ev)

13 PAO data: chemical composition ] 2 <X max > [g/cm 850 Auger ICRC proton iron QGSJETII-03 QGSJET01 SIBYLL2.1 EPOS E [ev]

14 PAO data: chemical composition ] 2 <X max > [g/cm 850 Auger ICRC proton iron QGSJETII-03 QGSJET01 SIBYLL2.1 EPOS E [ev] limits strongly all top-down or Z burst models

15 PAO data: chemical composition ] 2 <X max > [g/cm 850 Auger ICRC proton iron QGSJETII-03 QGSJET01 SIBYLL2.1 EPOS E [ev] limits strongly all top-down or Z burst models points to heavier composition at UHE

16 PAO data: chemical composition ] 2 <X max > [g/cm 850 Auger ICRC proton iron QGSJETII-03 QGSJET01 SIBYLL2.1 EPOS E [ev] limits strongly all top-down or Z burst models points to heavier composition at UHE supported by fluctuations of X max

17 What is the bonus of UHECR astronomy? astronomy with VHE photons restricted to few Mpc: 22 radio log10(e/ev) 16 photon horizon γγ e + e CMB 14 IR kpc GC 10kpc 100kpc Mpc Virgo 10Mpc 100Mpc Gpc

18 What is the bonus of UHECR astronomy? astronomy with VHE photons restricted to few Mpc: astronomy with HE neutrinos: large λ ν, but also large uncertainty δϑ > 1

19 What is the bonus of UHECR astronomy? astronomy with VHE photons restricted to few Mpc: astronomy with HE neutrinos: large λ ν, but also large uncertainty δϑ > 1 small event numbers: < few/yr for PAO or ICECUBE identification of steady sources challenging

20 What is the bonus of UHECR astronomy? proton horizon 18 log10(e/ev) 16 photon horizon γγ e + e CMB 14 IR kpc GC 10kpc 100kpc Mpc Virgo 10Mpc 100Mpc Gpc

21 What is the bonus of UHECR astronomy? proton horizon 18 log10(e/ev) kpc photon horizon γγ e + e use larger statistics of UHECRs well-suited horizon scale small enough deflections in magnetic fields? GC Virgo 10kpc 100kpc Mpc 10Mpc 100Mpc CMB IR Gpc

22 Energy losses, the dip and the GZK cutoff 1e-07 1e-08 (1/E)*dE/dt [1/yr] 1e-09 pion production pair production 1e-10 redshift 1e log10(e/ev) at E ev: N + γ 3K N + π starts and reduces free mean path to 20 Mpc pair production leads to a dip at ev

23 Possible anisotropies of extragalactic CRs: 1 Dipole anisotropy cosmolog. Compton-Getting effect induced by motion of Sun relative to cosmological rest frame requires λ CR (E) > λ LSS

24 Possible anisotropies of extragalactic CRs: 1 Dipole anisotropy cosmolog. Compton-Getting effect induced by motion of Sun relative to cosmological rest frame requires λ CR (E) > λ LSS 2 Anisotropies on medium scales z 0.2: spots with l degrees reflects LSS of matter, modified by B requires λ CR (E) < few λ LSS

25 Possible anisotropies of extragalactic CRs: 1 Dipole anisotropy cosmolog. Compton-Getting effect induced by motion of Sun relative to cosmological rest frame requires λ CR (E) > λ LSS 2 Anisotropies on medium scales z 0.2: spots with l degrees reflects LSS of matter, modified by B requires λ CR (E) < few λ LSS 3 Small-scale clustering Small-scale angular resolution of experiments CR from the same (?) point sources requires small qb/e and small N s

26 Possible anisotropies of extragalactic CRs: 1 Dipole anisotropy cosmolog. Compton-Getting effect induced by motion of Sun relative to cosmological rest frame requires λ CR (E) > λ LSS 2 Anisotropies on medium scales z 0.2: spots with l degrees reflects LSS of matter, modified by B requires λ CR (E) < few λ LSS 3 Small-scale clustering Small-scale angular resolution of experiments CR from the same (?) point sources requires small qb/e and small N s 4 Correlations with specific sources requires small qb/e and small N s

27 Correlations with AGNs: Auger analysis AGN from VCC catalogue:

28 Correlations with AGNs: Auger analysis first data set with data < May 2006 to fix cuts: E th = 56EeV, l 0 = 3.1 and d 75Mpc.

29 Correlations with AGNs: Auger analysis first data set with data < May 2006 to fix cuts: E th = 56EeV, l 0 = 3.1 and d 75Mpc. second data set May 2006 August 2007: 13 events, 8 correlated, 2.7 expected p ch

30 Correlations with AGNs: Auger analysis first data set with data < May 2006 to fix cuts: E th = 56EeV, l 0 = 3.1 and d 75Mpc. second data set May 2006 August 2007: 13 events, 8 correlated, 2.7 expected p ch just a 3 σ effect, test against isotropy, no propagation

31 Correlations with AGNs: Auger analysis first data set with data < May 2006 to fix cuts: E th = 56EeV, l 0 = 3.1 and d 75Mpc. second data set May 2006 August 2007: 13 events, 8 correlated, 2.7 expected p ch just a 3 σ effect, test against isotropy, no propagation AGN or something with similar distribution?

32 Correlations with AGNs: PAO analysis 27 CRs ( ) and 472 AGN ( ):

33 Correlations with AGNs: PAO analysis 27 CRs ( ) and 472 AGN ( ): Virgo does not contribute [Gorbunov et al. 08 ]

34 Energy threshold consistent with GZK horizon? 8 out of 13 CRs (E 57EeV) correlated within 75 Mpc: % 30 % 50 % 70 % 90 % 100 R [Mpc] e+19 1e+20 1e+21 E [ev]

35 Energy threshold consistent with GZK horizon? 8 out of 13 CRs (E 57EeV) correlated within 75 Mpc: % 30 % 50 % 70 % 90 % 100 R [Mpc] e+19 1e+20 1e+21 E [ev]

36 Energy threshold consistent with GZK horizon? 8 out of 13 CRs (E 57EeV) correlated within 75 Mpc: % 30 % 50 % 70 % 90 % 100 R [Mpc] 10 under-estimation of energy scale? or iron? or fake? 1 1e+19 1e+20 1e+21 E [ev]

37 Energy threshold consistent with GZK horizon? 8 out of 13 CRs (E 57EeV) correlated within 75 Mpc: % 30 % 50 % 70 % 90 % 100 R [Mpc] 10 under-estimation of energy scale? or iron? or fake? safer (but less ambitious) method? 1 1e+19 1e+20 1e+21 E [ev]

38 Comparing with sources: [A. Cuoco et al. 07, 08 ] Use the auto-correlation function, w(ϑ) = DD(ϑ) RR(ϑ) 1, where DD: number of pairs in catalogue RR: number of pairs in random sets for most popular sources of UHECRs:

39 Comparing with sources: [A. Cuoco et al. 07, 08 ] Use the auto-correlation function, w(ϑ) = DD(ϑ) RR(ϑ) 1, for most popular sources of UHECRs: AGN

40 Comparing with sources: [A. Cuoco et al. 07, 08 ] Use the auto-correlation function, w(ϑ) = DD(ϑ) RR(ϑ) 1, for most popular sources of UHECRs: AGN and GRB [ ]

41 Auto-correlation function of different sources: [A. Cuoco et al. 07 ]

42 Auto-correlation function of different sources: [A. Cuoco et al. 07 ]

43 Auto-correlation function of different sources: [A. Cuoco et al. 07 ]

44 Auto-correlation function of different sources: [A. Cuoco et al. 07 ] differences on all angular scales reduced statistical error reduced dependence on B: global comparison on all scales only relative deflections enter possible to constrain B

45 Auto-correlation function of different sources: [A. Cuoco et al. 07 ] differences on all angular scales reduced statistical error reduced dependence on B: global comparison on all scales only relative deflections enter possible to constrain B

46 Auto-correlation function of different sources: [A. Cuoco et al. 07 ] differences on all angular scales reduced statistical error reduced dependence on B: global comparison on all scales only relative deflections enter possible to constrain B

47 Auto-correlation function of different sources: [A. Cuoco et al. 07 ] differences on all angular scales reduced statistical error reduced dependence on B: global comparison on all scales only relative deflections enter possible to constrain B

48 Clustering signal for the PAO Science data [A. Cuoco et al. 08 ]

49 Clustering signal for the PAO Science data [A. Cuoco et al. 08 ] larger consistency of data with AGN than normal galaxies only consistency check, no independent evidence bad cross-correlation of old data [A. Cuoco et al. 07 ]

50 Effects of cluster fields [K. Dolag, MK, D. Semikoz 08 ] Sources sit in regions with ρ ρ and B B

51 Effects of cluster fields [K. Dolag, MK, D. Semikoz 08 ] Sources sit in regions with ρ ρ and B B what are effects of cluster fields?

52 Anisotropies of a single source at 1000 EeV/Z model z 1000 EeV

53 Anisotropies of a single source at 100 EeV/Z model z 100 EeV

54 Anisotropies of a single source at 10 EeV/Z model z 10 EeV

55 Anisotropies of a single source at 1 EeV/Z model z 1 EeV

56 Effects of cluster fields: [K. Dolag, MK, D. Semikoz 08 ] anisotropies hide cluster for part of observer 1 2 less 2 more 5 less P(δ) E [EeV]

57 Effects of cluster fields: [K. Dolag, MK, D. Semikoz 08 ] anisotropies hide cluster for part of observer modulate the energy spectrum 10 1 fit 1/E 2.2 no MF (0,0) (40,-10) (90,45) dn/de E [EeV]

58 Multi-Messenger Astronomy with Cen A? [] MK, S. Ostapchenko, R. Tomàs 08

59 Possible source/acceleration scenarios for Cen A: mechanism: shock acceleration vs. acceleration in regular fields location: core, hot spots, along the jet target: gas vs. photons

60 Possible source/acceleration scenarios for Cen A: mechanism: shock acceleration vs. acceleration in regular fields location: core, hot spots, along the jet target: gas vs. photons

61 Possible source/acceleration scenarios for Cen A: mechanism: shock acceleration vs. acceleration in regular fields location: core, hot spots, along the jet target: gas vs. photons

62 Possible source/acceleration scenarios for Cen A: mechanism: shock acceleration vs. acceleration in regular fields location: core, hot spots, along the jet target: gas vs. photons neglect acceleration fix 2 basic scenarios: core and jet fix n γ and n H by observations normalization of UHECRs by PAO AGN hypothesis

63 Chandra observation of X-ray emission in the jet 1 arcmin

64 Chandra observation of X-ray emission in the jet divide in subareas separate fit to gas column density X and spectral index α

65 Chandra observation of X-ray emission in the jet: Results 1 arcmin X = /cm 2 in the jet

66 Chandra observation of X-ray emission in the jet: Results 1 arcmin X = /cm 2 in the jet with d = 0.4kpc and σ pp = 150mbarn: interaction depth τ pp 0.01

67 Length scales for acceleration in the jet

68 Length scales for acceleration in the jet diffusion increases effective size

69 Length scales for acceleration in the jet diffusion increases effective size for pp no threshold τ = 1 for E = ev, optimal for neutrino telescope

70 Our two base models acceleration close to the core acceleration in accretion shock/regular fields pγ interactions τ γγ 1, synchrotron losses for e ± acceleration in jet shock acceleration pp interactions τ γγ 1, synchrotron losses for e ±

71 Results for acceleration in jet: broken power-law

72 Results for acceleration in jet: broken power-law

73 Results for acceleration in jet: broken power-law source with τ 1 visible in TeV range τ pp τ γγ

74 Results for acceleration in jet: broken power-law α = 2.7 required for diffuse CR flux in dip model disfavoured as spectrum of single source Cen A diffuse spectrum = superposition of single sources with dn/de max distribution HE γ observations constrain UHECR models

75 Results for acceleration in jet: α = 2

76 Results for acceleration in jet: α = 1.2

77 Results for acceleration close to the core: broken power-law

78 Results for acceleration close to the core: broken power-law source with τ pγ 1 (weakly) visible in TeV range UHE photons are reshuffled

79 Results for acceleration close to the core: broken power-law

80 Results for acceleration close to the core: α = 2

81 Results for acceleration close to the core: α = 1.2

82 Summary Cen A fixed n γ and n H by observations normalization of UHECRs by PAO AGN hypothesis

83 Summary Cen A fixed n γ and n H by observations normalization of UHECRs by PAO AGN hypothesis HE neutrino astronomy: exploiting directional signal (=muons) requires northern experiment event number most sensitive on steepness of CR spectrum: 10 4 few events per year

84 Summary Cen A fixed n γ and n H by observations normalization of UHECRs by PAO AGN hypothesis HE neutrino astronomy: exploiting directional signal (=muons) requires northern experiment event number most sensitive on steepness of CR spectrum: 10 4 few events per year if typical steady source, first detection of diffuse flux [Koers, Tinyakov 08 ]

85 Summary Cen A fixed n γ and n H by observations normalization of UHECRs by PAO AGN hypothesis HE neutrino astronomy: exploiting directional signal (=muons) requires northern experiment event number most sensitive on steepness of CR spectrum: 10 4 few events per year if typical steady source, first detection of diffuse flux HE gamma astronomy: all cases promising apart from α 1 [Koers, Tinyakov 08 ]

86 Summary Cen A fixed n γ and n H by observations normalization of UHECRs by PAO AGN hypothesis HE neutrino astronomy: exploiting directional signal (=muons) requires northern experiment event number most sensitive on steepness of CR spectrum: 10 4 few events per year if typical steady source, first detection of diffuse flux HE gamma astronomy: all cases promising apart from α 1 general: TeV photon sources may be also good neutrino sources [Koers, Tinyakov 08 ]

87 Summary Cen A fixed n γ and n H by observations normalization of UHECRs by PAO AGN hypothesis HE neutrino astronomy: exploiting directional signal (=muons) requires northern experiment event number most sensitive on steepness of CR spectrum: 10 4 few events per year if typical steady source, first detection of diffuse flux HE gamma astronomy: all cases promising apart from α 1 general: TeV photon sources may be also good neutrino sources pp may be more important than pγ in jet [Koers, Tinyakov 08 ]

88 General summary tension between horizon and fraction of correlated PAO events

89 General summary tension between horizon and fraction of correlated PAO events tension between chemical composition and correlation data from PAO

90 General summary tension between horizon and fraction of correlated PAO events tension between chemical composition and correlation data from PAO nuclei with admixture of protons?

91 General summary tension between horizon and fraction of correlated PAO events tension between chemical composition and correlation data from PAO nuclei with admixture of protons? auto-correlation more robust method than cross-correlation

92 General summary tension between horizon and fraction of correlated PAO events tension between chemical composition and correlation data from PAO nuclei with admixture of protons? auto-correlation more robust method than cross-correlation lensing in cluster and Galactic fields important

93 General summary tension between horizon and fraction of correlated PAO events tension between chemical composition and correlation data from PAO nuclei with admixture of protons? auto-correlation more robust method than cross-correlation lensing in cluster and Galactic fields important connection to TeV γ-rays, acceleration

Cosmic Rays, Photons and Neutrinos

Cosmic Rays, Photons and Neutrinos Michael Kachelrieß NTNU, Trondheim [] Introduction Outline Plan of the lectures: Cosmic rays Galactic cosmic rays Basic observations Acceleration Supernova remnants Problems