Using the Shell-Model Monte Carlo method and the Random Phase Approximation theory, we carry out an estimation of neutrino energy loss (NEL) for 55Co and 56Ni by electron capture. We find that the NEL rates increase...Using the Shell-Model Monte Carlo method and the Random Phase Approximation theory, we carry out an estimation of neutrino energy loss (NEL) for 55Co and 56Ni by electron capture. We find that the NEL rates increase greatly at some typical stellar conditions, and can even exceed five orders of magnitude (e.g. T9 = 38.5, Ye = 0.42 for 56Ni). On the other hand, the error factor C shows that the fit is fairly good for two results at higher density and lower temperature, and the max- imum error is - 1.2%. However, the maximum error is ,- 55.60% (e.g. T9 = 18.5, Ye = 0.45) at lower density and higher temperature.展开更多
Abstract G349.7+0.2 is an interacting supernova remnant (SNR) expanding in a dense medium. Recently, a very strong γ-ray source coincident with this SNR has been revealed by Fermi-LAT and H.E.S.S. ob- servations w...Abstract G349.7+0.2 is an interacting supernova remnant (SNR) expanding in a dense medium. Recently, a very strong γ-ray source coincident with this SNR has been revealed by Fermi-LAT and H.E.S.S. ob- servations which shows a broken power-law-like spectrum. An escaping-diffusion model, including the power-law and g-function injection, is applied to this source which can naturally explain the spectral fea- ture in both the GeV and TeV regime. We use the Markov Chain Monte Carlo method to constrain the model parameters and find that the correction factor of slow diffusion around this SNR, X-0.01 for power-law injection and X - 0.1 for g-function injection, can fit the data best with reasonable molecular cloud mass. This slow diffusion is also consistent with previous results from both phenomenological models and theoretical predication.展开更多
基金supported by the Advanced Academy Special Foundation of Sanya under Grant No. 2011YD14
文摘Using the Shell-Model Monte Carlo method and the Random Phase Approximation theory, we carry out an estimation of neutrino energy loss (NEL) for 55Co and 56Ni by electron capture. We find that the NEL rates increase greatly at some typical stellar conditions, and can even exceed five orders of magnitude (e.g. T9 = 38.5, Ye = 0.42 for 56Ni). On the other hand, the error factor C shows that the fit is fairly good for two results at higher density and lower temperature, and the max- imum error is - 1.2%. However, the maximum error is ,- 55.60% (e.g. T9 = 18.5, Ye = 0.45) at lower density and higher temperature.
基金the support of the National Natural Science Foundation of China(Grant No.11233001)973 Program(Grant 2015CB857100)+1 种基金he Educational Ministry of China(Grant 20120091110048)the program B for Outstanding PhD candidate of Nanjing University
文摘Abstract G349.7+0.2 is an interacting supernova remnant (SNR) expanding in a dense medium. Recently, a very strong γ-ray source coincident with this SNR has been revealed by Fermi-LAT and H.E.S.S. ob- servations which shows a broken power-law-like spectrum. An escaping-diffusion model, including the power-law and g-function injection, is applied to this source which can naturally explain the spectral fea- ture in both the GeV and TeV regime. We use the Markov Chain Monte Carlo method to constrain the model parameters and find that the correction factor of slow diffusion around this SNR, X-0.01 for power-law injection and X - 0.1 for g-function injection, can fit the data best with reasonable molecular cloud mass. This slow diffusion is also consistent with previous results from both phenomenological models and theoretical predication.