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广西大学—国家天文台天体物理与空间科学研究中心 China-VO and Astroinformatics
伽玛暴光学余辉光度函数 和60 cm 光学望远镜 王祥高 广西大学—国家天文台天体物理与空间科学研究中心 China-VO and Astroinformatics 2012· ·三峡大学
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Outline 1. GRB and it’s optical emission
2. Observed GRB Optical Brightness Distribution Function 3. MC simulation 4. Robotic 60-cm Telescopes of GXU-NAOC Center 5. Summary and Discussion
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1.伽玛暴 伽玛射线暴(Gamma-Ray Burst，GRB)是宇宙学距离上的宇宙大爆炸以来的最强的能量爆发事件，它的主要特点是伽玛射线波段流量突然增强，以及具有的瞬时性，能量高，时标短，光变曲线复杂多变等特点。 伽玛暴是宇宙中除宇宙大爆炸之外最激烈的爆发现象，在短时标类能照亮整个宇宙。
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科学意义 伽玛暴 引力物理 星系 恒星 物理 高能辐射过程 宇宙学 中心能源？ 喷流形成和演化？ 火球动能辐射？ 各种成份的物理起源？
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Shallow Decay Oneset 伽玛暴光变曲线 Distinct origins of various components ?
luminosity functions (LF) at t<1h ? Oneset Li, Liang et al. 2012, arXiv
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Outline 1. GRB and it’s optical emission
2. Observed GRB Optical Brightness Distribution Function 3. MC simulation 4. Robotic 60-cm Telescopes of GXU-NAOC Center 5. Summary and Discussion
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Data selection Sample: Corrections: k-correction, Galactic extinction
Full sample of GRBs with optical afterglow detection from , 230 GRBs included 146 well-sampled LCs for our analysis. Most of them were observed in the R-band. Optical data, prompt gamma-ray dataand redshift. Corrections: k-correction, Galactic extinction (No correction for host galaxy extinction )
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光度分布 Global lightcurves
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光度分布 Onset
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光度分布 shallow Decay
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光度分布
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Optical prompt emission of GRBs
目前已探测到伽玛暴～4000个； 但探测到爆发时光学辐射的<10个: GRB , , , A, B, , B 其中仅仅 GRB B有无时延观测！ GRB B
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Summary for the observations:
The observed distributions of R-band magnitude are roughly a Gaussian function. About 90% of GRBs in the above samples have R<20. This may be due to instrumental selection effect (only small robotic telescope can rapidly response to the GRB triggers). Prompt Optical Flares: More luminous, and the burst time is more early
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Outline 1. A generic Optical Lightcurves of GRBs
2. Observed GRB Optical Brightness Distribution Function 3. MC simulation 4. Robotic 60-cm Telescopes of GXU-NAOC Center 5. Summary and Discussion
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MC simulation Model (3)Extinction: (1)Optical luminosity function:
(2)GRB rate: Free parameters in our models:
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MC Result {α1=0.70, α2=1.9} Lb~ 1046 erg s-1
Our Monte Carlo (MC) simulations suggest that a intrinsic broken power-law luminosity function can well reproduced the observed magnitude distributions.
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Outline 1. GRB and it’s optical emission
2. Observed GRB Optical Brightness Distribution Function 3. MC simulation 4. Robotic 60-cm Telescopes of GXU-NAOC Center (Robotic Autonomous Observatory) 5. Summary and Discussion
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Space Multi-band Variable Objects Monitor
GRM VT MXT CXG SVOM Space Multi-band Variable Objects Monitor GWAC GFTs GWAC, an array of ground wide angle cameras nm sr (90*90 deg)
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GXU-NAOC Robotic Telescopes
Diameter: 60cm FoV: arcmin Colors: g,r,i (z) CCDs: k1k EMCCD 600mm (24") Ritchey-Chrétien System f/3 primary mirror with f8 System focal ratio LOMO Ritchey Chrétien optical set Mirror material zero to low expansion Astro-Sital ceramics L/8 PtV wave, >95% Strehl Direct Drive Mount speed 15°/sec. ( 25°/sec. optional) Pointing ：<3“ RMS with pointingfile Tracking precision： <0.15“ RMS in 5 minutes Encoder resolution： 0.007“ on the axis
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EMCCD 增益可显著地改善这种极微弱信号的信噪比，由此在大吞吐量的分析研究中可实现更快的采样和更短的曝光时间。
快速读出, 半导体制冷型（ -90 ℃ ）.
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Science goal of GXU-NAOC Robotic Telescopes
Fast time resolution light curves Prompt emissions Early afterglow Confirming GWAC On: Sub-arcsecond localization Multi-color diagram
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Swift SVOM 观测策略 伽玛暴坐标网络(GCN) 大型望远镜 GWAC 60 cm Robotic telescope
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中心集群机硬件配置与软件环境 ►管理及IO节点：1个， 2颗8核CPU ►计算节点： 5个，每个节点有2颗8核CPU,
计算核心总数80核，每个计算 节点的内存容量：32G，共160G ►速度：双精度浮点运算峰值每秒0.64万亿次 ►容量：磁盘阵列存储空间裸容量32T。 ►系统峰值功耗：约为5kW
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广西大学多功能计算平台网络拓扑图
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广西大学多功能计算平台 采用混合式的集群（Cluster）架构，计算节点80个（1036核）包括：
刀片式计算节点：69个， 每节点2颗六核处器 ； GPU节点： 个，每节点2颗八核处器 胖节点： 个，每节点8颗六核处器 速度： 双精度浮点运算理论峰值每秒15万亿次 节点总内存容量：2.56TB 分配磁盘总容量： TB
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