本文選題：球狀星團(tuán) + 脈沖星��； 參考：《云南大學(xué)》2016年博士論文

【摘要】：球狀星團(tuán)主要是由大量的低金屬豐度的年老恒星(特征年齡100億年)組成的球狀的自引力束縛系統(tǒng)。迄今為止,銀河系內(nèi)已經(jīng)發(fā)現(xiàn)了158個(gè)球狀星團(tuán)。2008年之前人們對(duì)這類源只探測(cè)到光學(xué)和射電輻射。Fermi衛(wèi)星成功發(fā)射后,球狀星團(tuán)的伽馬射線輻射被成功探測(cè),進(jìn)而被確認(rèn)為是一類新的伽馬射線輻射源。由于大部分球狀星團(tuán)的緯度低,受銀盤的彌漫背景伽馬射線輻射的影響顯著,因此認(rèn)證困難。迄今為止,伽馬射線球狀星團(tuán)的數(shù)目極其有限。為了可靠揭示伽馬射線輻射的起源并開(kāi)展統(tǒng)計(jì)研究,人們需要更大的樣本�；谶@一考慮,2014年以來(lái)我們系統(tǒng)的進(jìn)行了伽馬射線球狀星團(tuán)的搜尋并取得顯著進(jìn)展。2014年底我們分析了Fermi-LAT的Pass 7Rep的數(shù)據(jù),證實(shí)球狀星團(tuán)2MS-GC01和IC 1257是伽馬射線源,在球狀星團(tuán)NGC 5904、NGC 6656和FSR 1735的潮汐半徑內(nèi)發(fā)現(xiàn)了伽馬射線輻射存在的證據(jù)或跡象(見(jiàn)第2章)。2015年6月底,Fermi-LAT組公開(kāi)了Pass8的數(shù)據(jù),該數(shù)據(jù)與之前的版本相比對(duì)伽馬射線的能量分辨、角度分辨、有效探測(cè)面積等方面都有了顯著提高,這些提高對(duì)于尋找低緯度的暗弱源甚為關(guān)鍵。因此我們采用了近7年的Pass8數(shù)據(jù)來(lái)尋找新的伽馬射線球狀星團(tuán)(見(jiàn)第3章)。我們的數(shù)據(jù)分析證實(shí)了球狀星團(tuán)NGC 5904的伽馬射線輻射,并發(fā)現(xiàn)了球狀星團(tuán)M 15和NGC 6397的伽馬射線輻射,其中NGC 6397是距離最近的伽馬射線球狀星團(tuán)。我們用球狀星團(tuán)伽馬射線的光度估計(jì)了球狀星團(tuán)中的脈沖星的總數(shù)量。數(shù)據(jù)分析中沒(méi)有發(fā)現(xiàn)這些球狀星團(tuán)的伽馬射線流量存在明顯的變化,也沒(méi)發(fā)現(xiàn)它們的脈沖輻射。這表明所探測(cè)到的伽馬射線來(lái)自于一組而不是單個(gè)脈沖星的曲率輻射或者是脈沖星高能電子對(duì)星風(fēng)對(duì)低能光子的逆康普頓散射。我們也處理分析了2014期間雙星系統(tǒng)PSRB1259-63/LS2883在過(guò)近星點(diǎn)時(shí)的伽馬射線和X射線波段的數(shù)據(jù)。它的伽馬射線波段的流量在近星點(diǎn)后33天有一個(gè)很強(qiáng)的伽馬射線耀發(fā)。其流量強(qiáng)度大于它寧?kù)o態(tài)下流量的10倍。它的光變曲線在天量級(jí)甚至小于天量級(jí)的尺度上都有明顯的光變。伽馬射線和X射線的變化特征和2010/2011年此源的經(jīng)過(guò)近星點(diǎn)時(shí)的輻射特征幾乎一樣(見(jiàn)第4章)。在第5章我們對(duì)球狀星團(tuán)的研究成果進(jìn)行了小結(jié)并對(duì)利用我國(guó)暗物質(zhì)粒子探測(cè)衛(wèi)星數(shù)據(jù)來(lái)開(kāi)展這方面的工作的前景予以了展望。
[Abstract]:The globular cluster is a globular self-gravitational binding system consisting of a large number of low-metal-rich aged stars (characteristic age 10 billion years). To date, 158 globular clusters have been discovered in the Milky way. After the successful launch of the .Fermi satellite, which detected only optical and radio radiation from such sources before 2008, the gamma-ray radiation of the globular clusters was successfully detected. It is further recognized as a new type of gamma radiation source. Due to the low latitudes of most globular clusters, it is difficult to authenticate due to the obvious effect of the diffuse background gamma ray radiation on the silver disk. To date, the number of gamma-ray globular clusters is extremely limited. In order to reliably reveal the origin of gamma radiation and carry out statistical research, larger samples are needed. Based on this consideration, we have systematically searched gamma-ray globular clusters since 2014 and made significant progress. At the end of 2014, we analyzed Fermi-LAT 's Pass 7Rep data and confirmed that globular cluster 2MS-GC01 and IC 1257 are gamma ray sources. Evidence or signs of the presence of gamma radiation have been found in the tidal radii of the globular cluster NGC 5904 / NGC 6656 and FSR 1735 (see chap. 2). The Fermi-LAT group released Pass8 data at the end of June 2015, which compares with previous versions of the energy resolution of gamma rays. Angle resolution and effective detection area have been greatly improved, which is crucial for finding dark weak sources at low latitudes. So we have used the Pass8 data of nearly 7 years to find new gamma-ray globular clusters (see Chapter 3). Our data analysis confirms the gamma-ray radiation of globular cluster NGC 5904, and the gamma-ray radiation of globular cluster M15 and NGC 6397, in which NGC 6397 is the nearest gamma-ray globular cluster. We estimate the total number of pulsars in globular clusters by the luminosity of gamma rays of globular clusters. There is no obvious change in the gamma ray flux of these globular clusters or their pulse radiation in the data analysis. This indicates that the detected gamma rays are derived from the curvature radiation of a group of pulsars, not from a single pulsar, or from the inverse Compton scattering of low-energy photons by high-energy electrons from pulsars. We have also processed and analyzed the gamma ray and X ray band data of the binary system PSRB1259-63/LS2883 over the near star during 2014. Its gamma-ray band has a strong gamma-ray flare 33 days after the star. The flow intensity is 10 times greater than that under static condition. Its light change curve has obvious light variation on the scale of sky order or even less than sky magnitude. The variation characteristics of gamma rays and X-rays are almost the same as those of the sources passing near the stars in 2010 / 2011 (see chap. 4). In Chapter 5, we summarize the research results of globular clusters and give a prospect of using our country's dark matter particle detection satellite data to carry out this work.
【學(xué)位授予單位】：云南大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2016
【分類號(hào)】：P154.12

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1 張鵬飛;基于Fermi-LAT數(shù)據(jù)的球狀星團(tuán)研究[D];云南大學(xué);2016年

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