ON PROBABLE CONTRIBUTION OF NEARBY SOURCES TO ANISOTROPY AND SPECTRUM OF COSMIC RAYS AT TEV-PEV-ENERGIES

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1 ON PROBABLE CONTRIBUTION OF NEARBY SOURCES TO ANISOTROPY AND SPECTRUM OF COSMIC RAYS AT TEV-PEV-ENERGIES SVESHNIKOVA L.G. 1, STRELNIKOVA O.N. 1, PTUSKIN V.S. 3 1 Lomonosov Moscow State University, SINP, Moscow, Russia 3 Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radi Wave Propagation, Troitsk,Moscow, Russia sws@dec1.sinp.msu.ru

2 Amplitude of anisotropy GOALS Galacies Nearby sources of cosmic rays determines: Anisotropy of cosmic rays at all energies T>100 лет, R>100 pc T>10 5 yr, R>1kpc Energy GeV, ГэВ Proton Anisotropy Electron spectrum of cosmic rays at TeV- energies Fine structure of cosmic rays at PeV - energies Fermi-Lat Electron Spectrum interpretation The goal is to analyze real nearby and young sources from gamma astronomy catalogs and to calculate the probable contribution of CR from them to anisotropy of cosmic rays and to spectrum of cosmic rays at TeV-PeV energies Contribution around the knee (Erlykin& Wolfendale)

3 MODEL OF CR FLUXES CALCULATION To calculate a flux and anisotropy of cosmic rays near the Earth we use a semi-statistical approach : all sources are divided in 2 groups. A simple flat-halo Galaxy model of cosmic ray transport with halo boundaries at Hz = 4 kpc and Rg= 15 kpc, the particle propagation is described in terms of Green s functions, F= G (t i,r i, E ): R id =(D(E)t i ) 1/2 G i (t i, r, E) i ( r ) 2 i exp 2 Rid Qi E E 4 (, max ) 2 4H Rid S i D= E 0.33 cm 2 /s Q=AE -2.2 with Emax cutoff 2) sources of the second group are distributed randomly in time (with a birth rate 1/50 yr) and space (with account for the arm structure of Galaxy). 1) the first group selected from gamma astronomy catalogs contains real nearby young sources within R<1.5 kpc and ages < T near. =10^5 yr.

4 ESCAPE TIME DEPENDENT EMISSION If it is possible to see simultaneously cosmic rays and gamma sources? We take into account that maximal energy of accelerated particles decreases with time of SNR evolution Propagation time to the Earth depends on energy: 1 SNR is located at R=1 kpc 1 PeV 100 TeV SNR shell life 0,1 F E 3 0,01 1 TeV 1E-3 [18] ] Ptuskin, V.S. & Zirakashvili, V.N. 2005, A&A, 429, 755 1E Propagation time (years)

5 POTENTIAL NEARBY SOURCES Two types of SN explosions: SN Ia without neutron star remnants, being seen only in radio and X-ray catalogs of SNR; Core collapsed SNII and SNIbc with neutron star remnants, that can be seen also in other pulsar or PWN catalogs. 1) Green s catalog of 274 including 174 SNRs with measured distances; 2) catalog of 54 PWNe; 3) Fermi-LAT catalog of 46 gamma-pulsars; 4) ATNF catalog of of 1827 pulsars; 5) catalog of TeV sources of HESS [14]. The total number of selected gamma ray sources with determined ages and distances is 25 sources inside the circle r i < R near =1.5 kpc (10 with R<1 kpc) with age t i < T near = 10 5 yr. Most of sources are seen in several catalogs. The expected number of sources at birthrate of SN explosions, 1/50 yr, coincides well with the found number of nearby and young sources.

6 LIST OF NEARBY young sources R<1.5 kpc T<10 5 yr (25 events) SNR, Fermi-gamma PS, Hess -TeV, PWN, ATNF L град. Dmn Кпс T клет Name _SW G _SW DA495 _S Cygn Loop _S_F_ DR4 _S HB21 _S CTB104,DA551 _SWFP Boomerang _S P G _SWF_ CTA _S R5 _S HB9 _SW_P S147 _SW IC443, 3C157 HSWFP Vela X HSWF_ Vela Jun. HWFP FermiG343.1 HS J H HESSG353.6 P PSRB1916 FP Monogem W PWNG FP J

7 METHOD OF ANISOTROPY CALCULATION We calculated dipole anisotropy amplitude and direction α (right ascension) in the approximation of isotropic diffusion. The experimental procedure of two-dimensional anisotropy calculation was reproduced: the variation of counting rate in fixed declination belts on sidereal time is investigated : (α, )= (n(α, )- <n( )>) /<n( )> in different declination belts the grid of declinations (with 10 o strip) and right ascension (with α= 1 hour strip). For every cell (α k, δ k (E, r, t, α k, δ k ) = { i=1, Nr (3*D/c) / r i (G (t-t i,r-r i, E)) [sin i sin k + cos i cos k cos(α i - α k ) ]}/F (E,r)

8 Anisotropy amplitude Right Ascension (hours) PROTON ANISOTROPY AT ENERGY < 100 TEV (AND AT =0) 10-1 Fluctuations caused by random old sources are denoted as errors With Vela X With 10% Vela X E (GeV) Energy, GeV Fig. 6. Amplitude and right ascension of proton anisotropy produced by all sources calculated for δk =0: with Vela X (blue circles) and wit Vela X contribution reduced to 10% (red squares) in comparison with experimental data compilation from [9](black circles). (all sources accelerate up to 4 PeV) [9] Amenomori М et al Tibet AS Collaboration. Large-Scale Sidereal Anisotropy of Galactic Cosmic-Ray Intensity Observed by the Tibet Air Shower Array. Astro-ph/ v

9 VELA X PWN-PULSAR R~0.29 KPC, T~11000 YR Crab similar source has no clear shell

10 BASIC MODEL OF COMPOSITION AND EMAX OF GALACTIC SOURCES AT HIGH ENERGIES: Anisotropy at energy E depends on the number of sources being able to accelerate particles to energy E and on the diffusion coefficient D(E0/charge), so on chemical composition Four types of SNR havie different Emax: 1. Type Ia SNRs (Emax~4Z PeV) 25% sources are spread continuously in space and time 2. Type Ib/c SNRs (Emax~1Z PeV) 20% 4. Type IIb SNRs (Emax~600Z PeV) 3-5% 3. Type IIP SNRs (Emax~0.1Z PeV) <100 TeV V. Ptuskin, V. Zirakashvili, and Eun-Suk Seo, Spectrum of galactic cosmic rays accelerated in supernova remnants. Astrophysical J. T. 718 p

11 CONTRIBUTION OF NEARBY SOURCES TO ALL PARTICLE SPECTRUM 10 CC_SNR far and old SN Ia with 5 SNR_Ia No one SNIa (20%) provides the knee only one class of explosions with fixed parameters. F(E)*E ,1 Sum Nearby ~10% Sygn HB9 S147 HB21 SN IIn 4% Are there SNR Ia being able to accelerate to 4 PeV among our list of nearby sources? 0, E GeV The contribution of nearby sources is ~ 15% even in the extreme case when all shell like SN Ia accelerate up to 4 PeV

12 Str=F(E)/AE 3-1 Str=F(E)/AE 3-1 Str=F(E)/AE 3-1 FINE STRUCTURE OF SPECTRUM AROUND THE KNEE: = F(E)/AE-3-1 0,5 0,0 EAS Experiments EAS TOP Hires1st KASCADE GRANDE(2010):arXiv: v1 Kascade-Grande(2011) arxiv: v1 AE -3 Moscow workshop Large Scale Experiments..,.2011,May, uzmichev.pdf L.A.Kuzmichev. Tunka 133 Martirosov,A.Garyaka,etal.arXiv: [astro-ph.HE],and 0,5 0,0-0,5 He Fe H cno Si H2 He2-0,5 experiments Tunka-133 [6] Tunka - 25 Eas TOP Str=F(E)/E Gamma2010 [10] -1, ,5 E, GeV Tibet 2008 SYBILL HD: arxiv: v2 [hep-ex] -1, E, GeV 0,0-0,5 H He cno Si Fe H2He E, GeV

13 Anisotropy amplitude ANISOTROPY AMPLITUDE AROUND THE KNEE (AND AT =0) Compilation Amenomori et al. Tibet AS Astro-ph/ v Akeno, Yakutsk, KaskadeGrande KASCADE AUGER AGASA E, GeV Vela Jun 300 pc 700 yr no SNIa 1) Black thick line: no SNIa among nearby SNR, Vnearby=5% 2) Red thick line Sygnus Loop, HB9, HB21, R5, S147 accelerate to 4 PeV Vnearby= 15% 3) Intermediate cases : Both cases are not in contradiction with experiment due to two main factors: a) the increase of heavy nuclei abundance leads to decrease of diffusion coefficient at a given energy per particle; b) absence of nearby sources at R<600 pc being able to accelerate to 4 PeV and having the age around yr. 4) Blue line: Vela Jun. shell SNR is located at 300 pc and t=700 yr

14 Right Ascension, hours ANISOTROPY DIRECTION: RIGHT ASCENSION Vela Jun 0.3 kpc 700 y Information on anisotropy direction around the knee GeV is practically absent HB9 Sygnus Loop Auger One of the possible reason: Different position of anisotropy maximum for different nuclei at fixed energy per particle from one source -10 Akeno [] EAS TOP Energy, GeV

15 F(E) E 3.0 (m -2 sr -1 sec -1 GeV 2 ) ELECTRON SPECTRUM 10 2 Electrons "shell "+ "pulsar" electrons Background of "Shell" electrons Fermi HESS Atic12 Atic31rcrc AMS01 HEAT2001 1) Background of shell electrons is calculated with taken into account actual nearby sources and with reduced contribution of Vela X PAMELA positrons secondary positrons E (GeV) 2) Variant of calculation with the possible contribution of electron-positron flux from pulsars' magnetospheres: 2% of pulsars emit in e+e- pairs about erg in every source.

16 CONCLUSIONS We analyze real nearby and young sources from gamma astronomy catalogs and calculated the probable contribution of CR from them to anisotropy of cosmic rays and to spectrum of cosmic rays at TeV-PeV energies and above the knee.. Only one source Vela X- can give a significant contribution around TeV. But data on anisotropy imposed a limitation on a contribution of the Vela X remnant: it produces several times less CRs than an average shell in the Galaxy. A small anisotropy around the knee is explained by increase of heavy nuclei abundance through the knee and absence of the nearby source <500 pc being able to accelerate to 4 PeV. We do not see a good single candidate ( among known sources), that can give the noticeable contribution around the knee Class SN_Ia is a good candidate to knee producer due to small variety of explosion parameters. This model reproduces the fine structure of spectrum above the knee.

17 THANK YOU!

18 F(E)*E2.7 1 Heavy nuclei>si 0,1 Light nuclei <cno E GeV