伽玛暴光学余辉光度函数和 60 cm 光学望远镜

王祥高王祥高广西大学—国家天文台天体物理与空间科学研究中心

China-VO and Astroinformatics

2012·2012.11.28-12.02· 三峡大学

2

Outline1. 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

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。

科学意义

星系物理

恒星物理

高能辐射过程

宇宙学

伽玛暴

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？

…….

引力物理

5

Shallow Decay

Oneset

Li, Liang et al. 2012, arXiv1203.2332

Distinct origins of various components ?luminosity functions (LF) at t<1h ?

伽玛暴光变曲线

6

Outline1. 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

7

Data selectionData selection

Sample: Full sample of GRBs with optical afterglow detection

from 1997-2012, 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 )

8

光度分布

Global lightcurves

9

Onset

光度分布

10

shallow Decay

光度分布

11

光度分布

Optical prompt emission of GRBsOptical 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 990123, 041219, 050401, 050820A, 060111B, 061121, 080913B

其中仅仅 GRB 080913B 有无时延观测！

GRB 080913B

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

13

14

Outline1. 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

15

10 ])()[()( 21

bb L

L

L

LL

MC simulation Model

(1)Optical luminosity function:

(2)GRB rate:

(3)Extinction:

Free parametersin our models:

bL2

1

dzzdV

zzR

dzdtdN GRB )(

1)(

),()()( zzRzR SFRGRB

peakpeak

peakSFR zzz

zzzzR

,)1(

,)1()( 44.3

44.3

)2(

)10,2(ˆ),(

15.0

z

z

MC Result

16

{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.

17

Outline1. 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

GXU-NAOC(Two-60cm)Proceeding..

PROMT(Six-41cm)

KAIT(75cm)

BOOTES-4(60cm)

VTVTGRMGRM

CXGCXG

GFTsGFTsGWACGWAC

MXTMXT

GWAC, an array of ground wide angle camerasGWAC, an array of ground wide angle cameras 450-900nm 2sr (90*90 deg)

SVOMSVOMSSpace Multi-band pace Multi-band VVariable ariable OObjects bjects MMonitoronitor

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Diameter: 60cm

FoV: 10arcmin

Colors: g,r,i (z)

CCDs: 1k1k EMCCD

GXU-NAOC Robotic TelescopesGXU-NAOC Robotic Telescopes

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 Science goal of GXU-NAOC Robotic TelescopesRobotic Telescopes

Fast time resolution light curves Prompt emissions Early afterglow

Confirming GWAC On: Sub-arcsecond localization Multi-color diagram

GWAC

伽玛暴坐标网络(GCN)

大型望远镜60 cm Robotic telescope

Swift

SVOM

观测策略

► 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

中心集群机硬件配置与软件环境

广西大学多功能计算平台网络拓扑图

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： 10 个，每节点 2 颗八核处器

胖节点： 1 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： 135TB

广西大学多功能计算平台

Thanks