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Evolution of X-ray Binaries and the Formation of Binary Pulsars Xiang-Dong Li

Department of AstronomyNanjing University

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Millisecond Pulsar (MSP)-X-ray Binary (XRB) Relation

ATNF PSR Database

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Spin Frequency Distribution in LMXBs

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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) 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 Populations

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Binary Pulsar Populations

From Breton (2009)

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Classification of X-ray BinariesHigh-mass X-ray binaries

(wind-fed X-ray sources)

Supergiant HMXBs Be/X-ray binaries

Low-mass X-ray binaries (disk-fed X-ray sources)

Intermediate-mass X-ray binaries

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Stability of Mass Transfer

The characteristics of binary pulsars depends on mass transfer processes during the XRB phase

The stability of mass transfer depends on The mass ratio of the donor and accretor The evolutionary state of the donor

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Ways of Mass Transfer in XRBs Stable mass transfer

on nuclear timescale Thermal timescale

mass transfer Unstable mass

transfer common envelope

Deloye (2008)

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Initial – Final Binary Relation

Tauris & Savonije (2000)

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HMXB Evolution

Single mildly recycled NS

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Evolution of LMXBs

Close recycled PSR + He WD binary

Wide recycled PSR + He WD binary

Ultracompact X-ray binary or black widow X-ray binary

Nuclear evolution-driven mass transfer

Angular momentum-driven mass transfer

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Evolution of IMXBsIMXB LMXB

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Binary Pulsars Evolved from I/LMXBs

From Podsiadlowski et al. (2001)

LMXBs IMXBs

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Other Possibilities

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UC-LMXBs

TTMT

CV-like

RGB/AGB

PSR J1903+0327Ps=2.15 msPorb=95 daysMpsr~1.74 MsunM2>0.88 Msune = 0.44!

Comparison with Observations

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Mass Accretion and Mass Loss during LMXB Evolution

Zhang et al. (2011)

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Conclusions

The standard model for H/I/LMXBs can roughly reproduce the main features of the observed binary pulsars.

However, there are still many unresolved issues…