arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0908.2433astro-ph.HE
收藏

准热伽马射线暴谱模型的RHESSI检验

RHESSI Tests of Quasi-Thermal Gamma-Ray Burst Spectral Models

Eric C. Bellm

摘要:

瞬发伽马射线暴光谱在短时间尺度上演化,这表明时间分辨光谱拟合可能有助于诊断仍然未知的瞬发发射机制。我们使用RHESSI航天器的宽带伽马射线数据来测试具有高信噪比时间分辨光谱的九个明亮的伽马射线暴的准热模型。与在更窄的能带中报道的结果相反,准热模型的拟合质量与唯象能带函数的拟合质量较差。此外,最简单的准热模型,一个黑体加上非热功率定律的最佳拟合参数,显示出显着的依赖于拟合带。用更复杂的非热函数取代幂律的模型对于这里考虑的数据不鲁棒,并且降低了拟合黑体的物理相关性。

英文摘要:

Prompt gamma-ray burst spectra evolve on short time scales, suggesting that time-resolved spectral fits may help diagnose the still unknown prompt emission mechanism. We use broad-band gamma-ray data from the RHESSI spacecraft to test quasi-thermal models with high signal-to-noise time-resolved spectra of nine bright gamma-ray bursts. In contrast to results reported in more narrow energy bands, the quality of the fits of quasi-thermal models is poor in relation to fits of the phenomenological Band function. Moreover, the best-fit parameters for the simplest quasi-thermal model, a black body plus a nonthermal power law, show significant dependence on the fit band. Models that replace the power law with more complicated nonthermal functions are not robust for the data considered here and decrease the physical relevance of the fit black body.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑