引力波天文学与理论模型引力波理论建模课件.ppt

1、数值相对论与引力波建模数值相对论与引力波建模的一些新进展的一些新进展Zhoujian Cao(曹周键)Department of Astronomy,BNU2018-5-23第二届引力波天体物理学术研讨会第二届引力波天体物理学术研讨会Content Current state of GW theoretical model Finite element method to NR Theoretical model to eccentric binary system Summary and prospect引力波探测数据是典型的强噪声、弱信号匹配滤波方法是引力波数据处理的理想方法引力波理论模型

2、可以在既定硬件灵敏度的基础上很好地提高引力波探测的能力GW151226?13,5sigma引力波理论模型是波源参数反演的基础双黑洞?双中子星?星体质量、自旋？引力波天文学与理论模型引力波天文学与理论模型引力波理论建模引力波理论建模针对实际的波源天体，求解爱因斯坦方程没有对称性，解析解基本没有希望在极端条件下，近似方法失效数值计算成为主要依赖的方法(数值相对论NR)Current problems faced by NRCurrent NR codesPDE form used by AMSS-NCKUjjiijjijjkjkijijkjkjijjijjkjkijijiijkkkkijkjikj

3、kikijTFijjiijijkkkkijkjikijijiiijijiiiiiiAKAAtAAAAAAKRDDetAAtKKAADDtKKt3231)632(22322)2()(3222)31()(61)(4)(2PDE form for FEFE numerical schemeCao,Fu,Ji,and Xia,2018Shock forms,but really stable!Consistent to PDE property of non-linearly degenerateMore flexible than PSConvergence behavior better than

4、 FD,4th vs 2ndMore accurate than FD,2 orders betterComputation cost of NR 10 orbits,256 CPUs,7days GW150914:4 orbits GW151226:28 orbits3days x 250000=2055 years(256CPUs)GW150914State of art for EOBNR Total mass:0M Mass ratio:1q20 GW150914(1.24),LVT151012(1.77),GW151226(1.89),GW170104(1.61),GW170608(

5、1.71),GW170814(1.21)Spin:-1s0.9 GW150914(0.24),LVT151012(0.3),GW151226(0.35),GW170104(0.42),GW170608(0.3),GW170814(0.18)Precession simplified(BCV)GW150914,LVT151012&GW151226 assume no precession,GW170104,GW170608&GW170814 gain little constrain on precession e=0 All announced BBH GW events assumedLSC

6、,ApJ 818,L22(2016)Binary Black Hole with eccentric orbitPlausible source for LIGOMany sources for LISASEOBNRE modelAssume small eccentricity expansion (c)part effectively more than 4 PN Elip part about 2PNCao&Han,PRD 96,044028(2017)Not like adiabatic approximated model,consistent check for e=0 caseC

7、ompare to standard answer NRm1:m2=1:1e=0.02m1:m2=1:5e=0.02m1:m2=1:1e=0.2m1:m2=1:1000e=0.3a=0.9a=0.5a=-0.5a=-0.9ax-model for eccentric BBHadiabatic approximation modelm1:m2=1:1e=0.3More accurate than adiabatic model for later inspiral and merger 初步发展有限元数值相对论算法，希望实现大质量比双星系统和中子星双星系统准确建模 描述椭圆轨道双黑洞系统的引力波理论模型SEOBNRE准确可靠，可直接被LIGO数据处理使用 SEOBNRE模型可作为大质量比双黑洞系统理论模型的研究起点，发展未来空间引力波探测项目，如LISA，太极，天琴等，所需的双黑洞并合系统的理论模板Summary