Evolutionary Link between X-ray Pulsars and Millisecond Radio Pulsars
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Transcript of Evolutionary Link between X-ray Pulsars and Millisecond Radio Pulsars
Evolutionary Link between X-ray Pulsars and Millisecond Radio
Pulsars
李向东南京大学天文学系
2009-7-30
Radio Pulsars-Rotation Powered
X-ray Pulsars-Accretion Powered
LMXBsHMXBs
The Recycled Scenario
X-ray pulsars
Spin Periods
Millisecond X-ray Pulsars
Main type Sub-typeObservational examples
Recycled PSR + low-mass comp.(MC≤ 0.45M⊙)
PSR + (He) WDPSR J0437-4715PSR J1640+2224
Mildly recycled PSR + high-mass compact comp.(0.5≤MC/M⊙≤1.4)
1. PSR + NS (double)2. PSR + (ONeMg) WD3. PSR + (CO) WD
1. PSR B1913+162. PSR J1435-61003. PSR J2145-0750
Non-recycled pulsar (CO) WD + PSR PSR B2303+46
Un-evolved companion1. PSR + B-type comp.2. PSR + low-mass MS
comp.
1. PSR B1259-632. PSR B1820-11
Binary Pulsar Population
Binary Pulsar Population
Breton 2009
Stellar Evolution
Stellar Evolution
Evolution of HMXBs• Unstable mass transfer and common
Envelope evolution
Evolution of LMXBs
• Nuclear evolution• Mass and angular momentum loss
Form
ation Channel (1)
Single NS
TZO
TZO
Form
ation Channel (2)
Observations vs. Theories
Deloye 2008
Too long Porb or too small M2?
Black widow pulsars?
Problems with LMXB Evolution
• The formation of LMXBs requires a contrived evolution with– extreme initial mass ratio– ejection of a massive common envelope by a l
ow-mass star– survival as a bound system after the SN
Problems with LMXB Evolution
• Birthrate problem (Kulkarni & Narayan 1988)– NLMXB ~ 100, τLMXB ~ 10^9 yr– NBMSP ~ 10^5, τBMSP ~ 10^9-10^10 yr– NBMSP /τBMSP ~ 10-100 NLMXB /τLMXB
Problems with LMXB Evolution
• Mass and angular momentum loss
Andronov et al. (2001) Lattimer (2007)
Problems with LMXB Evolution
• Luminosity distribution
Podsiadlowski et al. 2002
PSR J1903+0327
• In the Galactic plane
• Ps=2.15 ms
Porb=95 days
• Mpsr~1.74 Msun
• M2~1 Msun
• e = 0.44!