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一个强大的射电源向银河系中心爆发.
Scott D Hyman1, T Joseph W Lazio, Namir E Kassim
1Department of Physics and Engineering, Sweet Briar College, Sweet Briar, Virginia 24595, USA. shyman@sbc.edu
Nature
|March 4, 2005
概括
天文学家在银河系中心附近发现了一个新的短暂无线电源,GCRT J1745-3009. 它独特的爆发特征表明了以前未知的宇宙短暂物种类型,为动态天体事件提供了洞察力.
科学领域:
- 无线电天文学 无线电天文学
- 天体物理学 天体物理学
- 暂时的天文现象是暂时的天文现象.
背景情况:
- 暂时的天文源往往意味着爆炸事件,通常由紧的物体提供动力.
- 无线电天文学提供了高时间分辨率的观测,但受限于狭窄的视野,导致动态无线电天空的采样很差.
- 广场仪器在X射线和玛射线频段经常检测短暂的来源,与目前的射电天文学能力不同.
研究的目的:
- 报告发现了一种新的短暂无线电源,GCRT J1745-3009.
- 描述这个新源的爆发性质,并将其与已知的无线电瞬态相比较.
- 探索其高亮度温度和能量密度对排放机制的影响.
主要方法:
- 利用银河系中心区域的适度宽场监测程序.
- 在0.33GHz频率进行观测.
- 分析了检测到的爆发的时间特征和光谱特性.
主要成果:
- 在银河系中心区域检测到一个短暂的无线电源,GCRT J1745-3009.
- 观测到的爆发特征与所有已知的无线电瞬态物种类别不同.
- 测得的亮度温度约为10^16 K,表明非常高的能量密度与连贯发射相一致.
结论:
- GCRT J1745-3009代表了一类以前未知的短暂无线电源.
- 这一发现凸显了新型广场射电望远镜发现新型天文现象的潜力.
- 这些发现表明,动态无线电天空可能还有许多未被发现的短暂类别.
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