Observation of TeV Gamma-Ray Emissions from Supernova Remnants

我们于2000年在南澳大利亚州建造了10米的空气切伦科夫望远镜，用于探测TeV伽马射线天体物理，并进行了观测。在本课题中，我们主要做了以下几方面的工作：(1)观测了SN1006、RXJ1713和RCW86三颗超新星遗迹。我们已经再次确认了SN1006和RXJ1713的TeV伽马射线发射，这两颗卫星都是用我们之前的3.8米望远镜探测到的TeV伽马射线。获得的TeV区附近的能谱表明，SN1006的TeV伽马射线发射可以用同步加速器-逆康普顿模型来解释，而RXJ1713的TeV伽马射线发射似乎是由于信噪比中加速质子产生的中性介子的衰变所致。我们还探测到了RCW86的TeV伽马射线发射的迹象，但还需要更多的观测来证实。(2)我们已经获得了伽马射线脉冲星PSR1706的TeV伽马射线发射谱，并在1TeV附近观察到了它的大破裂。我们还分析了这颗脉冲星的Chandla档案数据，得到了脉冲星和星云的分离光谱。结合这些新数据，我们得到了该脉冲星星云的多波长光谱，这显然表明TeV伽马射线发射不能用星云激波终止区域附近发生的同步加速器-逆康普顿过程来解释。(3)增加48个光管，增加了相机的视场。32路ADC和前端模块是为了获取光电管的模拟信息而开发的，并于2001年安装。现在，我们可以从所有512个光电管获得计时和模拟信息。对数据采集系统进行了改进，使触发频率从20赫兹提高到80赫兹，死区时间为20%。

We have constructed the 10m Air Cherenkov telescope at South Australia to explore TeV gamma-ray astrophysics in 2000, and operated for the observation until now. In this project, we have studied mainly followings.(1) In this period we observed three Supernova Remnants(SNR), SN1006, RXJ1713, and RCW86. We have reconfirmed TeV gamma-ray emissions from SN1006 and RXJ1713 from both of which TeV gamma rays were detected using our previous 3.8m telescope. Obtained spectra around the TeV region indicates that TeV gamma-ray emission from SN1006 can be explained by the Synchrotron-inverse Compton model, but that from RXJ1713 seems due to the decay of neutral pion generated by accelerated protons in the SNR. Also we have detected the sign of TeV gamma-ray emission from RCW86, but we need more observation for the confirmation.(2) Spectrum of TeV gamma-ray emission from the gamma-ray pulsar PSR1706 have been obtained, and the large breaking of it around 1 TeV has been observed. Also we analyzed the Chandla archive data for this pulsar, and obtained the separated spectra of the pulsar and its nebula. Combined those new data, we obtained the multi-wavelength spectrum of this pulsar nebula, which obviously shows that TeV gamma-ray emission can not be explained by the synchrotron-inverse Compton process occurred around the shock terminated region in the nebula.(3) We increased the field of View of the camera by increasing additional 48 phototubes. 32-ch ADC and Front end module were developed for getting the analog information of phototubes, and installed in 2001. Now we can get both timing and analog information from all 512 phototubes. Also the data acquisition system has been improved, and then the trigger rate could be increased from 20 Hz to 80 Hz with 20% dead time.