New Population Synthesis Models of the Cosmic UV Background
New Population Synthesis Models of the Cosmic UV Background
复制标题
宇宙紫外背景的新总体合成模型
DOI:
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发表时间:
2011
期刊:
影响因子:
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通讯作者:
P. Madau
中科院分区:
文献类型:
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作者:
F. Haardt;P. Madau
We present improved synthesis models of the evolving spectrum of the UV/X-ray diffuse background, updating and extending our previous results. A "minimal cosmic reionization model" is presented in which the galaxy UV emissivity traces recent determinations of the cosmic history of star formation, the luminosity-weighted escape fraction of hydrogen-ionizing radiation increases rapidly with redshift, from 1% at z=3 to 50% at z=8.5, the clumping factor of the intergalactic medium is C=3, and Population III stars make a negligible contribution to the metagalactic flux. The model provides a good fit to the hydrogen-ionization rates inferred from flux decrement measurements, and yields an optical depth to Thomson scattering, tau_e=0.085, that is in agreement with WMAP results.