【摘 要】
：
Recent precise measurements of cosmic-ray(CR)spectra show that the energy distribution of protons is softer than those of heavier nuclei,and there are spectral hardenings for all nuclear compositions
【机 构】
：
Key Laboratory of Dark Matter and Space Astronomy,Purple Mountain Observatory,Chinese Academy of Sci
【出 处】
：
第8届高海拔宇宙线探测国际研讨会(The 8th International Workshop on Air Showe
论文部分内容阅读
Recent precise measurements of cosmic-ray(CR)spectra show that the energy distribution of protons is softer than those of heavier nuclei,and there are spectral hardenings for all nuclear compositions above~200 GV.Models proposed for these anomalies generally assume steady-state solutions of the particle acceleration process.We show that if the diffusion coefficient has a weak dependence on the particle rigidity near shock fronts of supernova remnants(SNRs),time-dependent solutions of the lincar diffusive shock acceleration at two stages of SNR evolution can naturally account for these anomalies.The high-energy component of CRs is dominated by acceleration in the free expansion and adiabatic phases with enriched heavy elements and a high shock speed.The low-energy component may be attributed to acceleration by slow shocks propagating in dense molecular clouds with low metallicity in the radiative phase.Instead of a single power-law distribution,the spectra of time-dependent solutions soften gradually with the increasc of energy,which may be responsible for the "knee" of CRs.
其他文献
History of the Workshop ·V-01:HNU,April 2009,Shijiazhuang,China ·V-02:IHEP,Feb.2011,Beijing,China ·V-03:IPNO,Oct.2011,Orsay,Paris,France ·V-04:UN,Jan.2013,Naples,Italy
Content 1.Background 2.Status of WFCTA calibration system 3.The progress of simulation of the atmospheric calibration of WFCTA 4.Summary and next
Outline · Introduction and motivation · Description of the PRISMA-LHAASO project and prototypes · Results obtained with prototypes · Conclusions and future plans
Outline:Ⅰ.Auger Observatory description Ⅱ.Energy Spectrum Measurements Ⅲ.Composition Analyses Ⅲ.1 Xmax Distributions Ⅲ.2 Mixed Composition Analysis Ⅲ.3 Sd-Xmax Analysis.
Outline · KM2A:The high energy detector of LHAASO (10 TeV-1 PeV) · Simulation of KM2A · Choice of a fast simulation · Structure of the simulation
Motivation:We measure directly the spectra of Cosmic Rays only for:a single point in the Galaxy [the solar system] and a unique time (the present).
Content ·1.Introduction about LHAASO ·2.Status of LHAASO software ·2.1 Status of WCDA ·2.2 Status of WCDA++·2.3 Status of KM2A ·2.4 Status of WFCTA ·3.Status of LHAASO framework and future plan ·4.Sum
The Yangbajing Cosmic Ray Laboratory Tibet-China The ARGO-YBJ detector Single layer of RPCs detectors · Central carpet 78 × 75 m2 (95％ of active surface)
Content ·Status and difficulties in cosmic ray measurements ·Introduction of direct Cherenkov light ·Monte Carlo study based on LHAASO-WFCTA ·Improvement of the discrimination of heavy cosmic rays by
Tidal disruption event (TDE) 101 (Komossa 15 review) Figures from Rees 1988 Theory:· Inevitable:galaxies have supermassive black holes