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 HMXBs LMXBs

The Recycled Scenario Spin Periods X-ray pulsars

Millisecond X-ray Pulsars

Binary Pulsar Population Main type Sub-type Observational examples Recycled PSR + low-mass comp.(MC≤ 0.45M⊙) PSR + (He) WD PSR J0437-4715 PSR J1640+2224 Mildly recycled PSR + high-mass compact comp. (0.5≤MC/M⊙≤1.4) 1. PSR + NS (double) 2. PSR + (ONeMg) WD 3. PSR + (CO) WD 1. PSR B1913+16 2. PSR J1435-6100 3. PSR J2145-0750 Non-recycled pulsar (CO) WD + PSR PSR B2303+46 Un-evolved companion 1. PSR + B-type comp. 2. PSR + low-mass MS comp. 1. PSR B1259-63 2. PSR B1820-11

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

Formation Channel (1) TZO TZO Single NS

Formation Channel (2)

Observations vs. Theories Too long Porb or too small M2? Black widow pulsars? Deloye 2008

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 low-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!