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脉冲星研究的现状与展望. 乔国俊 北京大学文理学院天文学系. 脉冲星研究的现状与展望. I. 简介 II. 引力波的检测 III. 新天体的搜寻 IV . 对 “ 磁星 ” 的挑战 V . 广阔的前景 、 (守时性和导航). 近 50 年来的发现. Many discoveries over the past 50yr 脉冲星 微波背景 Cosmic Evolution Dark Matter in galaxies Quasars Jets + Superluminal motion 引力辐射间接验证 Aperture Synthesis
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脉冲星研究的现状与展望 乔国俊北京大学文理学院天文学系
脉冲星研究的现状与展望 I. 简介II. 引力波的检测III. 新天体的搜寻IV.对“磁星”的挑战V. 广阔的前景、(守时性和导航)
近50年来的发现 Many discoveries over the past 50yr 脉冲星 微波背景 Cosmic Evolution Dark Matter in galaxies Quasars Jets + Superluminal motion 引力辐射间接验证 Aperture Synthesis Cosmic Masers Giant Molecular Clouds 脉冲星的发现 大约70%脉冲星是Parkes 射电望远镜发现的
PSR 0329+54, P=0.715s PSR 0833-45, P=89 毫秒 PSR 1937+21, P=1.558 毫秒 PSR 1937+21: P=0.001,557,806,448,872,75(3)秒
High B Radio Pulsars SGRs, AXPs GRB Millisecond Radio Pulsars V. Kaspi 2006
Where we are… Pulses at 1/10th true rate
Thompson, astro-ph/0312272 Abdo et al. 2010,ApJS
脉冲星研究的现状与展望 I.研究历史简介II. 引力波的检测1)间接检测2)直接检测3)作为引力波源被检测III. 新天体的搜寻IV.对“磁星”的挑战V、广阔的前景
脉冲双星B1913+16 Hulse & Taylor , 1975
Post-Keplerian Timing Parameters:PSR B1913+16 Taylor, J.Astrophys.Astr.1995
PSR B1913+16 Weisberg, 2005
Rate of orbital period change in other gravitational theories, normalized to G.R Weisberg 2005
PSR J0737-3039 Kramer et al. 2005,astr-ph/0503386
The future fate of B1913+16 in 50 Million Year Timesteps Now 250 M.Y. Size of Sun Weisberg 2004
脉冲星研究的现状与展望 I.研究历史与已有成果II. 引力波的检测1)间接检测2)直接检测3)作为引力波源被检测III. 新天体的搜寻IV. 脉冲星是中子星还是夸克星?V. 脉冲星-磁星-伽玛暴
大爆炸(年) 0.00001 1 100,000 1,000,000 1,000,000,000 15,000,000,000 第 一 代 恒 星 今 天 宇宙 微波 背景 辐射 黑 暗 带 元素 形成 大爆炸
Direct Observations of gravitational waves (GW) GW: nanometers The Laser Interferometer Space Antenna (LISA) Base line:5 million KM, Frequency: 10-1 to 10-4HzObjects: Massive BH merging …
Direct Observations of gravitational waves (GW) Laser Interferometer Gravitational-wave Observatory (LIGO) in the USA consisting of two facilities, one at Hanford (WA) and the other at Livingston (LA), hosting two 4-km and one 2-km interferometers
Possible GW Possible detections of GW
Gravitational wave background Pulsars=arms of huge gravitational wave detectorSearch for spatial patterns in timing residuals! Manchester & Lyne, 2003
Error in Earth Velocity Manchester & Lyne, 2003 Quadrupole -Opposite sign in orthogonal directions Dipole-Opposite sign in opposite directions
脉冲星研究的现状与展望 I.研究历史与已有成果II. 引力波的检测1)间接检测2)直接检测3)作为引力波源被检测III. 新天体的搜寻IV. 脉冲星是中子星还是夸克星?V. 脉冲星-磁星-伽玛暴
Neutro-star/Neutron-star Inspiral Kip,S.T. 2001
Binary Black Hole Mergers Kip,S.T. 2001
Rogan,et al. astro-ph/0605034 Kip S. Thorne,2001
Gravitational wave background from Big Bang For example,van Straten et al. (2001) : over 40months of observing PSR J0437-4715obtained a residual root-mean-square of only 130 nsTo be improved. ~3GHzor higherDM(dispersion measure)
脉冲星研究的现状与展望 I.研究历史与已有成果II. 引力波的检测III. 新天体的搜寻脉冲星-黑洞;亚毫秒脉冲星; IV. 脉冲星是中子星还是夸克星?V. 脉冲星-磁星-伽玛暴
The BH-PSRsystem 1). Strong gravitational effects;2). Gravitational microlensing effects(Self-lensing by binary, Gould,1995)3). Effects of event horizon!4). Particle beam action with the BH
Supernova Stellar mass BH: a compact object with Mass>3Msun • neutron star neutron degeneracy pressure balances gravity • Oppenheimer • black hole so massive that nothing can balance gravity collapse to a point singularity Mass of an invisible star > 3 M⊙: black hole ! Zhang X.N., 2005
Difficulties to search for BH-PSR system Several groups have been searching for BH-PSR system, but It does not find one! ●For shout orbit period binary: it is very difficult to find it! DM, P, Tobt, e,… ●Can we find it at X-ray bands? Zhang, Qiao, Han, 1998,PABei,16,274
If a pulsar: P<0.5ms?=>Quark Star! Accretion induced collapse (AIC) of WD=>0.1ms SS Du,Xu,Qiao,Han,. MN, 2009
Possible test of SS and NS 1. Rotational period: SS can reach sub-millisecond2. Mass-radius.3. Solid strange star or NS?4. Binding energy of the surface. Bare strange star.Can we take a test from radiation: The difference between vacuum gap and free flow?
Pulsars: Neutron or quark stars? Neutron Stars v.s. QuarkStars http://chandra.harvard.edu/photo/2002/0211/0211_illustration.pdf “To probe pulsars by GW” http://vega.bac.pku.edu.cn/rxxu R. X. Xu
Milestones in detecting PSRs faster and faster Only possible in QS model ! Spin frequency Keplerian frequency (Mass-shedding limit) Stable axis-symmetric spin (GW radiation) P = 0.89ms (2007)? XTE 1739 Sub-ms periods (P < 1 ms) P = 1.4ms (2006) P = 1.6ms (1982) PSR 1748 PSR 1937 P = 33ms (1968) P ~ 1s (1967) Crab “To probe pulsars by GW” http://vega.bac.pku.edu.cn/rxxu R. X. Xu
脉冲星研究的现状与展望 I.研究历史与已有成果II. 引力波的检测III. 新天体的搜寻IV.对“磁星”的挑战V. 广阔的情景
High B Radio Pulsars 反常X射线脉冲星(AXP) & 软伽玛重复暴(SGR) SGRs, AXPs Radio Pulsars Millisecond Radio Pulsars V. Kaspi 2006
Basic observations:AXP • spin periodsP: 2-- 12 s , 10 Know • Pdot≈10-13to 10-11 s/s, spinning down • Large timing noise • Edot< LX • spin down time scales:103—105 yr • verysoft X--ray spectra • lack of bright optical counter parts • SNR Mereghetti, et al. astroph/0205122
Basic observations:SGR • super-outbursts1044reg/s • (low-energy gamma-ray and X-ray bursts) • Observations for AXP: • spin periods P: 5-- 8 s • Pdot ≈ 10^-13 to 10-11 s/s • Large timing noise • Edot <LX • soft X--ray spectra • secular spin down on time scales: 103—105 yr • lack of bright optical counter parts • SNR Mereghetti, et al. astroph/0205122 7-29-2009
Models Edot < LX == • Accretion => energy • B => energy: Magnetar • Glitch NS => energy • Quark star => energy
对 magnetar 模型的挑战 • 射电脉冲星J1847-0130 ●Anti-Magnetar: PSR J1718-3718 PSR J1852+0040 B~9.4 × 10^13 G ; Lx = 5.3×10^33 erg/s B~7.4 × 10^13 GX-ray E_dot = 3.0 × 10^32 erg s^−1 Bs = 3.1×10^10 G 强磁场≠》 X-ray 辐射 辐射≠》强磁场 • Radio: XTE J1810–197 AXP 1E 1547.05408 AXP 1E2259+586, 射电 《≠》弱磁场 B~5.9 × 10^13 G