UNVEILING THE SUPER ORBITAL UNVEILING THE SUPER ORBITAL UNVEILING - PowerPoint PPT Presentation

4 th FAN workshop, Hong Kong UNVEILING THE SUPER ORBITAL UNVEILING THE SUPER ORBITAL UNVEILING THE SUPER-ORBITAL UNVEILING THE SUPER-ORBITAL MODULATION OF LS I +61 303 IN X-RAYS MODULATION OF LS I +61 303 IN X-RAYS Jian Li ( 李劍 ) Special thanks to Shu Zhang Diego F Torres Daniela Hadasch Jianmin Wang et al Special thanks to Shu Zhang, Diego F. Torres, Daniela Hadasch, Jianmin Wang et al. Institute of High Energy Physics , Chinese Academy of Sciences Institut de Ciencies de l’Espai (IEEC-CSIC)

Outline Out e LOGO • Introduction • Introduction • Evidence of super-orbital modulation observed in X-ray & Model implication b d i X & M d l i li ti • Summary

1 . Introduction of LSI +61 303 LOGO LSI +61 303: HMXB, 2 ± 1 kpc, orbit period: 26.496 ± 0.0028 days. or Blackhole Companion: B0 Ve star M Mass: ~12.5 ± 2.5 M ⊙ 12 5 ± 2 5 M Radius: ~10 R ⊙ Compact object: 1 4 M with Compact object: 1-4 M ⊙ with unknown nature. Conventional model for Conventional model for a Be/X-ray binary The picture is based on a diagram from Snow (1987, in Physics of Be stars , Cambridge University Press).

1 . Introduction of LSI +61 303 LOGO or Blackhole Conventional model for Conventional model for a Be/X-ray binary The picture is based on a diagram from Snow (1987, in Physics of Be stars , Cambridge University Press).

1 . Introduction of LSI +61 303 LOGO Orbital geometry (26.5 days period) of LS I +61 Superior conjunction Apastron 303 LS I +61 303 is visible in radio X-ray to very high radio, X ray to very high energy (GeV and TeV) Periatron Inferior conjunction V.Zabalza et al. 2011 A&A

1. Introduction of LSI +61 303 LOGO C Compare to ~26.5 days orbit period, a 1667 days super-orbital period is t 26 5 d bit i d 1667 d bit l i d i detected first in radio (Gregory 2002) and then in H α emission lines (Zamanov et al. 1999) 1667 days ~ 63 orbits~ 4.6 years

1 . Introduction of LSI +61 303 LOGO H α emission comes mainly from the Be star disk (Hunushik H α emission comes mainly from the Be star disk (Hunushik, Kozok & Kaizer 1988) and its equivalent width stands for the size of the disk. or Blackhole H α emission line of LSI + 61 303 (Liu & yan, 2005 New Astronomy)

1 . Introduction of LSI +61 303 LOGO • Super-orbital modulation in radio and H α promotes us to find p p similar modulation evidence in X-ray and link it to the mass loss rate of the Be star. • J. Li et al. 2012 • • M Chernyakova et al 2012 M. Chernyakova et al. 2012 In soft X-ray: RXTE/PCA, more than 4 years (2007-08-28 till 2011-09-15) In hard X-ray: INTEGRAL/ISGRI, 10 years (2002-12-28 till 2012-11-24)

3-30keV LOGO 0.2 0.6 1.0 1.4 1.8 Orbital Phase

• Image of LSI + 61 303 by LOGO INTEGRAL/ISGRI in 18- INTEGRAL/ISGRI in 18 60 keV. • 12.45 sigma detection 12.45 sigma detection under 807ks exposure time • 200 days 200 d binned light curve curve

2. Evidence of super-orbital LOGO modulation in X-ray d l ti i X • Super-orbital Super orbital lightcurve in hard X-ray hard X ray

2. Evidence of super-orbital LOGO modulation in X-ray d l ti i X 3-30keV PCA results • Super-orbital modulation in hard X-ray is in phase with soft X-ray

Radio(1977-2000) optical LOGO X-ray Optical(1989-1999) p ( ) X-ray X (2007-2011, soft) radio (2002 2012 hard) (2002-2012, hard) X-ray super-orbital modulation is in phase with H α , lagged by radio at about p , gg y 300 days, 0.2 super-orbital phase Li et al, 2012 ， ApJL

TeV LOGO io radi P Peak flux per orbit in k fl bit i TeV shown in red (all of them happening in H α the 0 6 1 0 the 0.6–1.0 H orbital phase range) as a function of super-orbital phase super-orbital phase, together with radio, H α , GeV and X-ray GeV data data G X-ray 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 Super-orbital phase (0-2) J. Li et al, 2012

2. Model implications LOGO p But could LS I + 61 303 be different ? But could LS I + 61 303 be different ? J. Li et al, 2012

2. Model implications LOGO p In 2008, a very short (0.16s) X-ray burst detected from it by Swift/BAT, lead to the suggestions that the system may contain a magnetar. (Torres et al, 2012, ApJ ) If it is a magnetar, it is likely subject to a flip-flop behavior and shift from behaving as a pulsar being rotationally powered near apastron to g p g y p p being a propeller near periastron, along each of the system’s orbit ( Torres et al. 2012; Zamanov et al. 1995, 2001 ).

2. Model implications LOGO p A sketch of the Ejector Propeller model Ejector-Propeller model. The dashed lines indicates The dashed lines indicates the orbit of the neutron star.

2. Model implications LOGO p TeV o radio H α V GeV X-ray 0 0.4 0.8 1.2 1.8 2.0 Super-orbital phase (0-2)

LOGO 2. Model implications p

LOGO 2. Model implications p

TeV LOGO io radi P Peak flux per orbit in k fl bit i TeV shown in red (all of them happening in H α the 0 6 1 0 the 0.6–1.0 H orbital phase range) as a function of super-orbital phase super-orbital phase, together with radio, Ha. GeV and X-ray GeV data data G X-ray 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 Super-orbital phase (0-2) J. Li et al, 2012

3. Summary y LOGO Summary: 1. We found evidence for super-orbital variability in X-rays 3. There is a phase shift about 300 days in super-orbital modulation 3 Th i h hift b t 300 d i bit l d l ti between radio and X-ray. 4. The equivalent width of the H α emission line is in phase with X-ray variation 5. TeV emissions seems to be related to the super-orbital variability, but because of limited data, it is still unconfirmed.

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