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Cosmic-rays and Astrophysics

Cosmic-rays and Astrophysics. Part I : CR-hadronic components. Part II:. electron and g -components. Toru Shibata. Aoyama-Gakuin University 18/Aug/2010. Part I : CR-hadronic components. contents (1) :. 1) Energy budget of CRs in our Galaxy.

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Cosmic-rays and Astrophysics

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  1. Cosmic-rays and Astrophysics Part I : CR-hadronic components Part II: electron and g-components Toru Shibata Aoyama-Gakuin University 18/Aug/2010

  2. Part I : CR-hadronic components contents (1) : 1) Energy budget of CRs in our Galaxy 2) Acceleration mechanism of CRs 3) Enviroments of our Galaxy (ISM & ISRF) 4) Propagation of CRs in our Galaxy 5) Comparison with experimental data

  3. all -particle spectrum 1/m2sec electron (～1/100) cosmic-ray flux (m2ssrGeV)-1 1/m2year 1/100km2year 1/1km2year FNAL LHC Energy (eV)

  4. 1) Energy budget of CRs in our Galaxy： intensity= dI/dE [cm-2sec-1sr -1GeV-1] ∫ energy density = (4p/c)× E[dI/dE]dE ～1eV/cm3 all energy～1eV/cm3 ×pr2h disk volume d d ～1055erg power req. ～1055 erg/107y CR life tme ～3 ×1040erg/sec power of SN expl.～1051~52 erg/30y freq. of SN expl. ～1041~42erg/sec

  5. 2) Acceleration mechanism of CRs 1949, Fermi, Phys. Rev. 75, 1169 2nd order Fermi acceleration DE E E´ B plasma ~ 10-8 ; excellent with power form !!! but with b > 10 !!! b =[1~2] E: CR

  6. problem in 2nd-order Fermi acceleration colli. prob. +(vM /c)E 1 +vM /c ： head-on colli. DE = E´- E = DE = 2(vM /c)2E -(vM /c)E 1 -vM /c ：rear-end colli. k-2+a ~ 10-8 magnetic cloud vM～20km/s E´ vM CR E; v～c (1-dimensional)

  7. 1977, Krymsky, Dok. Akad. Nauk. SSSR 234, 1306; Axford, et al., Proc. 15th ICRC, 11, 132 shock front u1 u2= u1 /x r1 r2= xr1 x > 1 (Landau & Lifshiz, 1982) CR (for strong shock) upstream downstream !!! pressure

  8. 3-1) Enviroment of our Galaxy (ISM)

  9. 3-2) Enviroment of our Galaxy (ISRF) transparent for hadron components

  10. 4) Propagation of CRs in our Galaxy (hadronic components)

  11. Dh : Diff. coeffi. Dh : Diff. coeffi. (constant) (constant) nh : Gas density nh : Gas density Ginzburg-Ptuskin model (Diffusion-halo model) halo 2 ～3 kpc (~ 0) Dg : Diff. coeffi. disk (constant) .2 ～.3 kpc SS ng : Gas density 20 ～30kpc halo 2 ～3 kpc (~ 0)

  12. our model with stochastic reacceleration in ISM (revival of 2nd-order Fermi accereleation)

  13. key parameters in hadrnic components: g : indexin CR source spectrum in Galaxy not observable a : index in CR leakage rate from Galaxy possible, but .. b = g +a : index of CR spectrum observed at SS observable Xesc(r; R): leakage (escape) length possible a -a Xesc R with -g E0

  14. basic transport equation confinement for CR < H > = < Huni > H = Huni + Hran < Hran > = 0 scatt. and diff. for CR 1 magnetic cloud 3 ～ l1pc vM ～20km/s v～c CR D = cl ～3×1028 cm2/s

  15. general transp. eq. for hadronic CRs E- loss decay density colli. with j i colli. j i decay source average energy-loss and -gain fluctuation in energy gain

  16. solution for1-ry components （） for steady state ; survival probability (ApJ, 2004, 612, 238)

  17. solution for 2-ry components emissivity of secondary products at r : 1-ry production rate of 2-ry (p, He ,…) (p, B, Be,g, X, n…) 10 intensity for charged components : survival probability (ApJ, 2006, 642, 882)

  18. 5) Comparison with experimental data Observables: ●1-ry rich components (p, He, …, Fe) ●2-ry stable components (Li, Be, B,…) ●2-ry unstable components (10Be, 26Al, …) ● antiprotons parameters appearing in hadron components: ● (disk-to-halo ratio) ● (average path length at SS) or ● (reacceleration efficiency) ●

  19. launching mid. July level flight at 32km exp. time ～ 150hrs recovery dismounting early August process. mid. Aug. Performance of RUNJOB experiments construction early May (ISAS, ICRR)

  20. normalized CR density atSS Energy spectra for 1-ry components 2.6-2.8 (ApJ, 2004, 612, 238)

  21. Ｘ colli. with ISM 2-ry components ! relative abundance ：CR ：SS ：GS normalized to C = 100 atomic number Z

  22. secondary-to-primary ratio (2009) (ApJ, 2006, 642, 882)

  23. radio-nuclide : ) ( : life time of radio-nuclide : halothickness : isotope spread Galactic plane additional parameter:

  24. radio-nuclide abundance ratios (ApJ, 2007, 655, 892) normalized to note 15-20% uncertainty ins-frag.

  25. antiproton production : _ p + p p + p + p + p + anything Astropart. Phys. 2007, 27, 411

  26. antiproton-to-proton ratio (ApJ, 2008, 678, 907) (2010)

  27. Part II : electron and g-components contents (2) : 0) Motivation in this talk 1) Energy loss of electrons in ISM and ISRF 2) Comparison with data on electrons 3) Hadron-induced and e--induced g-rays 4) Comparison with data on g-rays 5) Summary and open questions

  28. 0) Motivation: Is there signal of novel source in e∓’s, γ’s, and p’s ? - three anomalies are recently reported 1) diffisive-γ spectrum in EGRET(1997; 2005) 2) electron spectrum in ATIC & PPB-BETS (2008) 3) positron spectrum in PAMELA (2009)

  29. Boer, W. 2005 CERN COURIER 45, 17

  30. Chang et al. 2008, nature

  31. Positron fraction astro-ph 0810.4995

  32. two anomalies : 1) diffusive-γ spectrum in EGRET(1997; 2005) 2) electron spectrum in ATIC & PPB-BETS (2008) both are denied by FERMI (2009)

  33. our approach to anomalies in CR data (I) Internal consistency in CR observables: ◎1-ry rich components (p, He, . . . Fe) ◎1-ry poor components (ultra-heavy elements) ◎1-ry (poor) electron components ◎2-ry stable components (Li, Be, B, . . . , ) ◎2-ry unstable components (10Be, 26Al, . . . , ) modeling check of CR propagation, and interstellar environment of our Galaxy

  34. - (II) Emissivityofe∓’s, γ’s, p’s from astronomical origin - - S≡ e+, γ, p hadron-induced : P ≡ p, He, . . . Fe electron-induced : P ≡ electrons S≡ n,X, γ ; , ,

  35. - (III) Emissivity of e∓’s, γ’s, p’s from cosmological origin emission site ? ;qDM(r) ??? prod. E-sp. ? ; fDM(E)

  36. Elementary processes of CRs in the Galaxy - p + Hp, K, p, p, … (ISM) 1. strong int. C + H B, Be , . . . , + X (ISM) 10 - pm +n, m e +n +n, … 2. weak int. Be Be , Al Al, . . . 26 27 10 9 ionization., bremsstrahlung (ISM) 3. E-M int. synchrotron, inverse comp. (ISRF) ◎dark matter (DM)annihilation 4. novel sources ? ◎primordial black hole (PBH)

  37. energy-loss (-gain) of electrons at SS energy-gain

  38. additional parameters in electron components energy density of ISRF number density of ISM inverse of path length in eVcm-2 inverse of path length in cm-2 or gcm-2

  39. submitted to ApJ

  40. 3) g-rays ●　hadron-induced ●electron-induced (●extragalactic contribution)

  41. production cross section of g-rays in p-p collision p + p g + anything Astrop. Phys. 23(2005)510

  42. due to detection bias

  43. (compiled by Stecker)

  44. extragalactic g-ray spectrum

  45. Latitudinal distribution of diffuse g ’s

  46. Longitudinal distribution of diffuse g ’s

  47. submitted to ApJ Energy spectrum of diffuse g ’s

  48. submitted to ApJ Energy spectrum of diffuse g ’s

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