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LMXBs as progenitors
- f millisecond pulsars
Alessandro Patruno
Astronomical Institute A. Pannekoek University of Amsterdam
2
RECYCLING SCENARIO
Image credit: Bill Saxton (NRAO)
LMXBs as progenitors of millisecond pulsars Alessandro Patruno - - PowerPoint PPT Presentation
LMXBs as progenitors of millisecond pulsars Alessandro Patruno - - PowerPoint PPT Presentation
LMXBs as progenitors of millisecond pulsars Alessandro Patruno Astronomical Institute A. Pannekoek University of Amsterdam RECYCLING SCENARIO Image credit: Bill Saxton (NRAO) 2 ACCRETING MILLISECOND PULSARS 14 AMXPs known Spin
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ACCRETING MILLISECOND PULSARS
14 AMXPs known
Spin Frequencies:182-599 Hz
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14 AMXPs known
Spin Frequencies:182-599 Hz
ΩK=√ GM R
3
ACCRETING MILLISECOND PULSARS
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14 AMXPs known
Spin Frequencies:182-599 Hz
P mag= B
2
8π >> P gas , Pram ΩK=√ GM R
3
ACCRETING MILLISECOND PULSARS
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14 AMXPs known
Spin Frequencies:182-599 Hz Magnetospheric Radius
Pmag= B
2
8π >>(P gas, P ram) ΩK=√ GM R
3
ACCRETING MILLISECOND PULSARS
˙ ν ∝ ˙ M 6/7 B
2/7
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14 AMXPs known
Spin Frequencies:182-599 Hz Magnetospheric Radius
Pmag= B
2
8π >>(P gas, P ram) ΩK=√ GM R
3
Hot Spots
ACCRETING MILLISECOND PULSARS
˙ ν ∝ ˙ M 6/7 B
2/7
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8
See review Patruno & Watts 2012
AMXP FAMILY
XTE J1814-338 AQL X-1 (19 hrs)/Intermittent SAX J1748.9-2021 Intermittent IGR J17511-3057 Swift J1749.4-2807 Eclipsing IGR J17498-2921 SAX J1808.4-368 Anomalous orbital evolution HETE J1900.1-2455 Intermittent/B Screening IGR J00291+5934 Fastest spin (599 Hz) XTE J1751-305 (He) XTE J0929-314 (He or C/O) XTE J1807-294 (He or C/O) Small donor (0.007 Msun) Swift J1756.9-2508 (He) Small donor (0.007 Msun) NGC 6440 X-2 (He) Small donor (0.007 Msun)
Porb>3.5hr 1hr<Porb<3.5hr Porb<1hr
Peculiarities
Porb
MS/SubG BD WD
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SPIN DISTRIBUTION
Accreting ms Pulsars See Galloway's talk on Type I burst sources
Patruno & Watts 2012, Tauris 2012 (Science 335), Tauris 2012 (arXiv1210.2598)
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RECYCLING SCENARIO
3b. 2b.
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PSR J1023+0038 1.69 ms spin period 4.8 hr orbital period
Archibald et al. (2009, 2010), Wang et al. (2009, 2010)
Accretion disk in 2001
RADIO PULSAR/X-RAY BINARY LINK
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Archibald et al. (2009, 2010), Wang et al. (2009, 2010)
RADIO PULSAR/X-RAY BINARY LINK
Does the accretion disk form/destroy on a timescale of ~10 yr ? How can the disk form again ? How does the pulsar spin evolve ?
Non-degenerate companion Eclipses for 50% of the time Red-back
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AMXP FAMILY
XTE J1814-338 4.3 hr 314 Hz
AQL X-1
19 hr 550 Hz SAX J1748.9-2021 8.8 hr 442 Hz IGR J17511-3057 3.5 hr 245 Hz Swift J1749.4-2807 8.8 hr 518 Hz IGR J17498-2921 3.8 hr 401 Hz
SAX J1808.4-368 HETE J1900.1-2455 IGR J00291+5934 XTE J1751-305 (He) XTE J0929-314 (He or C/O) XTE J1807-294 (He or C/O) Swift J1756.9-2508 (He) NGC 6440 X-2 (He)
Porb>3.5hr 1hr<Porb<3.5hr Porb<1hr
MS/SubG BD WD
Redbacks ?
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SAX J1808.4-3658: A Hidden Radio Pulsar ?
Homer+ (2001); Burderi+ (2003); Campana+ (2004); Deloye+ (2008); Wang+ (2009) See D'Avanzo+ (2009) for optical counterparts of more AMXPs in quiescence
Lq=5×10
31 erg/s
Lirr>4×10
33 erg/s
Irradiated Disk Fails to Explain Observations
See also Iacolina+ (2009, 2010) for AMXPs radio searches
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SAX J1808.4-3658 SAX J1808.4-3658 Orbital Period: 2.01 hr ˙ Pb=3.5×10
−12 s/s
¨ Pb=1.6×10
−20s/ s 2
'98 '00 '02 '00 '00 '05 '08 '11 Time
Orbital Evolution
Pb ˙ Pb ≈70 Myr
Patruno et al. 2012; Burderi et al. 2009; Hartman et al. 2008, 2009; Di Salvo et al. 2008
See PSR J2051-0827 in radio (Lazaridis et al. 2011)
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See review Patruno & Watts 2012
AMXP FAMILY
XTE J1814-338 4.3 hr 314 Hz
AQL X-1
19 hr 550 Hz SAX J1748.9-2021 8.8 hr 442 Hz IGR J17511-3057 3.47hr 245 Hz Swift J1749.4-2807 8.8 hr 518 Hz IGR J17498-2921 3.8 hr 401 Hz SAX J1808.4-368 2 hr 401 Hz HETE J1900.1-2455 1.4 hr 377 Hz IGR J00291+5934 2.5 hr 599 Hz
XTE J1751-305 (He) XTE J0929-314 (He or C/O) XTE J1807-294 (He or C/O) Swift J1756.9-2508 (He) NGC 6440 X-2 (He)
Porb>3.5hr 1hr<Porb<3.5hr Porb<1hr
MS/SubG BD WD
Redbacks ? Black Widows ?
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10 20 30 40 50 60 70 80 90 100
- Nr. LMXBs
Nuclear Powered Accretion powered
?
NON-PULSATING LMXBs
Intermittent Pulsating Non pulsating sources
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˙ νs∝exp(−t / τ)
MAGNETIC SCREENING
Patruno 2012
˙ νs∝B
2/7 ˙
M
6/7
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∂B ∂t =∇×(v×B)−c ∇× J σ
Cumming et al. 2001, Cumming 2008
MAGNETIC SCREENING
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SPIN DISTRIBUTION
Evolutionary processes Magnetic Field Screening Low Accretion Rates
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MISSING PIECES
Do sub-ms pulsars exist ? Where do we need to look for them ? Do AMXPs turn cyclically on as radio ms pulsars ?