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Cosmic Rays and Astrophysics: Exploring Hadronic and Electron Components

This research paper by Toru Shibata from Aoyama-Gakuin University reviews cosmic rays (CRs), focusing on their hadronic and electron components. Part I investigates the energy budget, acceleration mechanisms, and propagation of CRs within our Galaxy, analyzing data from experimental observations and theoretical models of CR intensity and spectra. Part II discusses electron interactions in the interstellar medium and radiation field, comparing with recent observational data highlighting anomalies in electron and positron spectra. The study aims to deepen the understanding of cosmic ray behavior and its implications for astrophysics.

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Cosmic Rays and Astrophysics: Exploring Hadronic and Electron Components

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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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