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X-ray enhancement and long-term evolution of Swift J1822.3-1

606arXiv:1310.2758

Authors: O. Benli, S. Caliskan, U. Ertan et al.

Reporter: Fu, Lei

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Outline

• Introduction• Long-term evolution of Swift J1822.3-16

06• X-ray enhancement of Swift J1822.3-16

06• Discussion and Conclusions

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Introduction

• Swift J1822.3-1606 was discovered on 2011 July 14

• a SGR-like burst and associate with outburst

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Introduction• The observation of ROSAT in 1993• 0.1–2.4 keV• count rate 0.012

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Introduction

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Introduction

• Swift J1822.3-1606 is the second low-B magnetar

•

• Quiescent luminosity ~ erg/s

G105-2 ~ 13B

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Introduction

• In magnetar model– toroidal and dipole fields of and

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IntroductionRea et al. 2012

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Introduction

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Introduction

• This work– Fallback disk model– Determine the evolutionary epoch and the field stre

ngth of this source– Explain the X-ray enhancement of this source

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Long-term evolution of Swift J1822.3-1606

• Critical parameter

– Initial surface density profile

– Hot-Cold viscosity transition

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Long-term evolution of Swift J1822.3-1606

– Initial outer disk radius

– X-ray irradiation flux

C~– Mass transfer is conservative

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Long-term evolution of Swift J1822.3-1606

• The spin evolution– AXP/SGR are sources accreting in spin-do

wn phase

– accretion

– accretion stops

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Long-term evolution of Swift J1822.3-1606

in units of

,except for dashed line

P0=300ms

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X-ray enhancement of swift J1822.3-1606

• Disk piles up caused by the SGR burst

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Discussion and conclusions

• the properties in quiescent state– accretion– no accretion

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Discussion and conclusions

Both the X-ray enhancement and long-term evolution can be explained in the frame of fallback disk model

The model sources with the dipole field strength in the

range on the pole of the star and with the initial periods greater than ~55ms can reach the X-ray luminosity and the rotational properties of Swift J1822.3-1606 simultaneously

When accretion stop the variation in could be observed with out a significant change in the observed luminosity of the source

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Quantum spindown of highly magnetized neutron stars

arXiv:1310.1938Authors: B. Lamine, C. Berthiere,

A. DupaysReporter: Fu, Lei

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• vacuum magnetized by the rotating dipole m -->

• due to retardation effect a spin-down torque will excerted on the NS

• the energy loss rate is

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• in the classical dipole spin down

• Spin evolution

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• when period derivative has minimum value

• when quantum contribution will be dominant

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the evolution of crab pulsar in 50kyr

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Constraints on the mass and radius of NS

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Thanks