GRB Afterglow Photometry with Herschel Infrared Cameras

GRB Afterglow Photometry with Herschel Infrared Cameras (GRAPHICS)<br><br>Gammaray bursts (GRBs) are the most luminous explosions in the universe. It has been difficult to obtain a full spectral picture of the phenomena in the short period when GRBs become ..alive., i.e. when they generate bursts in Gammaray and produce afterglows in other wavelengths. Between NIR (12micron) and submillimeter (850micron) there lies nearly two orders of magnitude of spectral range where GRB afterglows have never been detected. Herschel is unique in its cutting edge sensitivity, efficiency, and readiness in FIR observations, and is capable of detecting GRB afterglows. Observing GRB afterglows with Herschel would greatly enrich our understanding of GRB physics and conditions of the Universe in early epochs.<br><br>We propose Target of Opportunity studies using the SPIRE and PACS instruments of Herschel to observe 3 bright GRB afterglows, each within a few hours to a few tens of days after burst. We will make followup observations after the initial one to photometrically measure GRB light curves and IR SEDs. We will make ground optical observations to compliment Herschel data, and have the the GRB community informed. Observing the forward shock peak in the FIR light curve and compare it (both the flux and time) with those in the optical and radio bands would give a unambiguous test to the fireball model, and offer a direct measurement of the density profile of the circumburst material. Catching the shortlived reverse shock emission and measure its magnitude would lead to constraints on some important parameters of the GRB ejecta and address the unknown composition of GRBs, baryonic vs. magnetic. [truncated!, Please see actual data for full text] [truncated!, Please see actual data for full text]

Herschel红外相机GRB余辉光度测量（GRAPHICS）

伽马射线暴（GRBs）是宇宙中最明亮的爆炸现象。在GRBs爆发并产生伽马射线暴光和其它波长上的余辉的短暂时期内，获取该现象的完整光谱图像一直是一项挑战。在近红外（12微米）与亚毫米波（850微米）之间，存在近两个数量级的光谱范围，其中GRB余辉从未被探测到。Herschel以其在远红外波段的尖端灵敏度、效率和随时待命的优势而独树一帜，能够探测到GRB余辉。利用Herschel观测GRB余辉将极大地丰富我们对GRB物理学和宇宙早期时期条件的理解。

我们提出利用Herschel的SPIRE和PACS仪器进行机会目标研究，以观测3个明亮的GRB余辉，每个余辉均在爆发后数小时至数十天内进行观测。我们将在首次观测后进行后续观测，以光度测量GRB光曲线和红外光谱能量分布。我们将进行地面光学观测以补充Herschel数据，并向GRB研究界通报。在远红外光曲线中观测前冲击波峰值，并将其（包括通量和时间）与光学和射电波段中的数据进行比较，将对火球模型进行明确的检验，并直接测量爆发周围物质的密度分布。捕捉短暂的逆冲击波辐射并测量其亮度，将有助于约束GRB喷射物的一些重要参数，并解决GRBs的未知组成问题，即重子性对磁性的问题。[内容截断！请参阅实际数据以获取全文][内容截断！请参阅实际数据以获取全文]