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Fine structure, mass composition, peaks Л.Г.Свешникова
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Tibet Kascade Grande MSU EAS TOP TUNKA GAMMA F(E)/AE -2.9 -1 and TUNKA STRUCTURE: F(E)/AE -3 -1 knees and pronounced peak, GAMMA F(E)/AE -3.0 -1 Line- our model – one of calculated variants
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Basic MODEL: V. Ptuskin, V. Zirakashvili, and Eun-Suk Seo, Spectrum of galactic cosmic rays accelerated in supernova remnants. Astrophysical J. T. 718 p. 31–36. Several types of SNR: 1. Type Ia SNRs (Emax~4 Z PeV) with the following parameters: kinetic energy of explosion E = 10 51 erg, number density of the surrounding interstellar gas n = 0.1 cm−3, and mass of ejecta Mej = 1.4Ms can accelerate particles to the energy of the knee. 2. Type Ib/c SNRs (Emax~1 Z PeV) with E = 10 51 erg exploding into the low density bubble with density n = 0.01 cm −3 formed by a progenitor star as a Wolf- Rayet star. The ejecta mass is Mej = 2Ms and k = 7. 3. Type IIP SNRs (Emax~0.1 Z PeV) with parameters E=10 51 erg, n = 0.1 cm−3, Mej = 8M, and k = 12. 4. Type IIb SNRs (Emax~600 Z PeV) with E = 3 10 51 erg, n = 0.01cm −3, and Mej = 1Ms. Before entering the rarefied bubble, the blast wave goes through the dense wind emitted by the progenitor star during its final RSG stage of evolution. It was assumed that the mass loss rate by the wind is M˙ = 10−4M yr−1 and the outer wind radius is 5 pc. In this model sources are distributed continiously, the random nature of sources Is not considered
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Extension of this model takes into account a statistical nature of sources: Distant and old sources are simulated randomly Nearby ( Rnear~1.-1.5 кпс ) and Young Tnear~105 лет) are taken from gamma astronomy catalogs The propagation time of 4 PeV protons is around 10 4 years (less than survival time of shells and PWNs, so we try to identify gamma-atronomy detected source and cosmic ray source.
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Additional suggestings: 1)All SNR Ia (thermonuclear explosions accelerate up to Emax =4 PeV (23%) 2)Collapsing SNR II, SNIbc have distributed Emax from 1 TeV to 1000 TeV: This results in additional d ~0.17, and observed near Earth obs = sour + d + d prop ~2.705 sour =2.2. 3) and 2-5 % SNIIn accelerated up to 6 10 17 eV. 3) Chemical composition: 37% of H, 35% of He, 8% CNO, 10% of CNO, 8 % of intermediate nuclei, 10% of Fe.
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Spectrum without propagation Structures can be explained only if the cutoff in source spectrum is strong d >2.5 -3.0 Fe - peak can be explained only if we suggest “bump” before cutoff energy Main variant
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1) bump around 4 PeV is produced by proton and helium nuclei with nearly equal abundances 2) concavity above 10 16 eV denotes the transition to CNO and more heavier nuclei, the amount of Fe nuclei at that should be not less than 1/3 of He nuclei. 3) sharp break around the 10 8 GeV marks the transition to the contribution of rare SNIIb being able to accelerate protons up to 6x10 17 eV comprising the several percents among all SNR. The slope of spectrum (-3.24+-0.08 in KG) in the model is connected with the slope of cutoff. 4) If we exclude SNIIb we can not describe the flat spectrum above the 10 16 eV. 5) Two variant of calculation: Main 1 (absence of SNRs in the Earth vicinity with Emax=4 PeV) and Main 2 (where 4 SNRs accelerate to 4 PeV) give more or less similar structures around the knee Here we need to know MetaGalactic P He C,O Fe Si Total all particle spectrum in our model ( F(E)*E 3) has fine structures Galactic sources
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Contribution of nearby actual sources Variant 1: No one SNR <1 kpc can accelerate to 4 PeV Total contruution: 7% in total Variant 2: all pure shell SNRs < 1 kpc accelerate to 4 PeV Total contribution 30% in total We did not find the actual single sources that can imitate the fine structure
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Variant without “bump” in source spectrum can not describe Fe-peak, but describe structures
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Variant with wide (0.5 order) “bump” in source spectrum can describe Fe-peak more or less
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Variant with narrow (0.25 order) “bump” in source spectrum can describe Fe-peak completely, but there is a some contradiction with the main knee – it becomes too narrow and with 2 ears
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Mass composition in 3-d variant coincides with Tunka -133 last data
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Mass composition: 3 dif. variants 1) Emax (P) In Galaxy ; 4 PeV 2) Emax (P)=4 and 600 PeV This variant predicts a heavy composition at 10 18 eV 3) SNR Ia + He stars +MetaGalactic with mixed composition in sources
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Implications of the cosmic ray spectrum for the mass composition at the highest energies D. Allard1, N. G. Busca1, G. Decerprit1, A. V. Olinto1;2, E. Parizot1 Figure 3. Propagated spectra obtained assuming a mixed source composition compared to HiRes (left) and Auger (right) spectra, the dierent components are displayed.
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Variant with Meta-galactic with mixed composition and with He-stars (without heavy nuclei) instead of SNIIn
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Amplitude and Right ascension of anisotropy around the knee
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Conclusions about Fe-peak To get in our calculations Fe-peak we need to introduce some bump in source spectrum with a width 0.3 or 0.1 of the order. Single nearby source could not help in this problem. First a very impressive fact – a very good coincidence of positions of the Fe peak and position of P-He main knee at the suggestion of normal composition. In the case of narrow peak (1/10 of order) Fe peak is reproduced perfectly, but the main knee should be visible as two knees. May be if we take into account an accuracy of energy and mass determination, it helps to smooth these peaks. The nature of the bump in a source spectrum is not clear fully. But it can reflect the time dependent emissions – most energetic particles are emitted at the beginning of the acceleration process, when the speed of shock wave is maximal. This bump should be seen during 10 4 ears (time of collecting of PeV signal from the sources due to propagation) and should be variable in the time.
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Propagation Time for different energies We can identified
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Всего 25 с R <1.5 кпс и T <10 5 лет (всего 73 до 3 кпс) Чистые SNR 6 (без пульсаров, похожие на сверхновые Ia (25%). В 19 есть либо PWN (11 штук) либо гамма-пульсар (11 штук), Из 19 HESS зарегистрировал ТэВ-ное излучение только в 30 %, Из 6 SNR - только в 1 (Только в J1713-3946) Тэвное излучение. Используемый набор потенциальных источников КЛ.
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Приложение I. HSWFPL град. Dmn Кпс T клет Name _SW__65.30.820.G65.3+5.7 _SW__65.71.50.DA495 _S___74.00.4420.Cygn Loop _S_F_78.21.57.7.DR4 _S___89.00.819.HB21 _S__93.71.5120.CTB104,DA551 _SWFP106.30.810.Boomerang _S__P114.30.77.7G114.3+0.3 _SWF_119.51.414.CTA _S___127.11.20.R5 _S___160.90.86.6HB9 _SW_P180.00.84.6S147 _SW__189.11.520.IC443, 3C157 HSWFP263.90.2911.0Vela X HSWF_266.21.310.Vela Jun. HWFP343.11.418.FermiG343.1 HS___347.31.01.6J1713-3946 H____353.60.827.HESSG353.6 ___P49.11.488.PSRB1916 ___FP201.10.29110.Monogem __W__291.01.00.PWNG291.02-0.11 ___FP201.20.7544.J0631+1036 __WF__7.41.768.J1809-2332 H__F_80.21.6120.J2032+4127
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