天文学报
天文學報
천문학보
ACTA ASTRONOMICA SINICA
2015年
3期
218-224
,共7页
伽马射线暴%宇宙学：宇宙背景辐射
伽馬射線暴%宇宙學：宇宙揹景輻射
가마사선폭%우주학：우주배경복사
gamma-ray bursts%cosmology：cosmic background radiation
从过去的威尔金森微波各向异性探测器(Wilkinson Microwave Anisotropy Probe)到现在的普朗克卫星(Planck satellite)，宇宙微波背景辐射图的反常现象已经被广泛地认知。其中一个反常是：从l =2到l =5的多极矩存在耦合现象。为了考察伽马射线暴中是否存在与微波背景辐射相同的反常现象，研究了伽马射线暴的角分布。对伽玛暴样本的角分布进行球谐函数展开，得到前几项展开项的系数，发现从l =2到l =4有一定程度的耦合，而l =5与前面几个极矩相距较远。而且，四极矩分布是趋近平面化的，而其他几个极矩没有这样的特征。
從過去的威爾金森微波各嚮異性探測器(Wilkinson Microwave Anisotropy Probe)到現在的普朗剋衛星(Planck satellite)，宇宙微波揹景輻射圖的反常現象已經被廣汎地認知。其中一箇反常是：從l =2到l =5的多極矩存在耦閤現象。為瞭攷察伽馬射線暴中是否存在與微波揹景輻射相同的反常現象，研究瞭伽馬射線暴的角分佈。對伽瑪暴樣本的角分佈進行毬諧函數展開，得到前幾項展開項的繫數，髮現從l =2到l =4有一定程度的耦閤，而l =5與前麵幾箇極矩相距較遠。而且，四極矩分佈是趨近平麵化的，而其他幾箇極矩沒有這樣的特徵。
종과거적위이금삼미파각향이성탐측기(Wilkinson Microwave Anisotropy Probe)도현재적보랑극위성(Planck satellite)，우주미파배경복사도적반상현상이경피엄범지인지。기중일개반상시：종l =2도l =5적다겁구존재우합현상。위료고찰가마사선폭중시부존재여미파배경복사상동적반상현상，연구료가마사선폭적각분포。대가마폭양본적각분포진행구해함수전개，득도전궤항전개항적계수，발현종l =2도l =4유일정정도적우합，이l =5여전면궤개겁구상거교원。이차，사겁구분포시추근평면화적，이기타궤개겁구몰유저양적특정。
Anomalies of the cosmic microwave background (CMB) maps have been widely acquainted nowadays via the Wilkinson Microwave Anisotropy Probe (WMAP) satellite and the Planck satellite. One anomaly is a multipole alignment from l = 2 to l = 5. In our work, we investigate the angular distribution of gamma-ray bursts (GRBs) to find whether there exists an anomaly similar to that of CMB. We perform a spherical harmonics expansion on the GRB samples to derive coe?cients of a few multipole terms. A rough alignment from l = 2 to l = 4 exists, while the l = 5 multipole points to a different direction. The quadrupole is obviously planar, while the other ones are normal.
