X–ray binaries : X–ray binaries

X–ray binaries :

• X–ray binaries :

• Degenerate primary ( NS , BH)
• 1035 erg s-1 < Lx < 1039 erg s-1
• Low Mass X-ray Binaries (LMXB)
• High Mass X-ray Binaries (HMXB)

Young luminous massive stars

• Young luminous massive stars

• 2 types :

• Supergiant X-ray binaries
• Be/X-ray pulsar ( BeX )

• Supergiant X-ray binaries

• Supergiant companion star
• Mass : 18 - 20 Msun
• P < 10 days
• Accretion modes : radially outflowing stellar wind

Be star + X-ray pulsar

• Be star + X-ray pulsar
• 2 discs : - Be equatorial disc
• - NS accretion disc

• 3 possible periods

• Pulse period
• Orbital period
• Super-orbital period
• (such as in A0538-66)

MMW / MSMC ~ 50

• MMW / MSMC ~ 50

• 65 known HMXB in our galaxy

• Now, we know 47 HMXBs in SMC

• Studying the temporal properties of SMC/LMC X-ray binaries
• Why are these SMC HMXBs all neutron star systems? where are the BH equivalents?
• Do any of these BeX have the same properties as BeX system A0538-66 which shows a 421 days superorbital periodicity? What is causing this ?
• Do any of this large number of HMXBs show properties similar to the microquasar SS433 ?

Data used : long-term database.

• Data used : long-term database.

• MACHO [MAssive Compact Halo Objects]
• ( Alcock et al., 1996)
• 1.25 m telescope at Mount Stromlo Observatory, Australia
• Data available : from 1992 June - 2000 January
• OGLE [ Optical Gravitational Lensing Experiment]
• ( Udalsky et al,. 1997)
• 1.3 m Warsaw telescope
• at Las Campanas observatory, Chile
• Phase II : January 1997 - ~ Dec 2000
• Phase III : June 2001 - until now

We combined the light curves from MACHO, OGLE II, and OGLEIII of all known BeX.

• We combined the light curves from MACHO, OGLE II, and OGLEIII of all known BeX.

• Macho data available from : http://wwwmacho.anu.edu.au/Data/MachoData.html

• OGLE II data : http://ogle.astrouw.edu.pl/

• OGLE III data : http://ogle.astrouw.edu.pl/ogle3/xrom/xrom.html

• Run Starlink PERIOD (package) to study their temporal properties.

Porb : 16.65 days

• Porb : 16.65 days

• Super-orbital period : ~ 421 days

• Formation and depletion of the Be equatorial disc

• TBB ~ 20-50 eV

• Lbol ~ 1037 - 1038 erg s-1

• SSS system :

• WD
• Sub-giant companion
• High accretion rate , > 10-7 Msun yrs-1

• WD burns H steadily at its surface

• Contraction model : (Southwell et al., 1996)

• accretion rate drops Optical luminosity decreases
• rise in Teff
• increase in X-ray luminosity

• CAL 83 : X-ray emission occurs only during optical low state

• ( Grenier & Di Stefano, 2002)

X-ray data : ROSAT

• X-ray data : ROSAT

• Optical : MACHO ( blue )

Finding more sources showing similar behaviour to A0538-66 using OGLE III data.

• Finding more sources showing similar behaviour to A0538-66 using OGLE III data.

• Why the compact object of all of these HMXBs are neutron star?

• More understanding on the Supersoft X-ray binary

• Investigating the variability of all these Be/X-ray pulsar if any of these has a periodicity comparable to 162 days as seen in SS433.

• Finding the next SS433-like (continuous and precessing jets[disc]) among those HMXB in SMC .

• Publish the result

SS433 : first known X-ray binary that emits relativistic jet

• SS433 : first known X-ray binary that emits relativistic jet

• Only continuously emitting micro-quasar

• Key feature :

• inclination : 79o e < 0.05 (Margon & Anderson 1989)

• Jet velocity : 0.26 d = 5.5 kpc (Blundell et al. 2004)

• Porb = 13.08 days Pprec = 162.5 days (Abell & Margon,1979)

• f

Some BeX sources shows similar behaviour to A0538-66.

• Some BeX sources shows similar behaviour to A0538-66.

• SSS CAL83 and RXJ0513.9-6951 show a variability in a timescale 450 days and 167.94 days respectively.

• We still need more Ogle III data or other long term optical data for some sources.

• Investigation of the next SS433-like among those large number of HMXB needs to be done

Grimm et al. ,2003, Astron. Astrophys. Vol. 3 , Suppl., 257–269

• Grimm et al. ,2003, Astron. Astrophys. Vol. 3 , Suppl., 257–269

• Coe et al., 2008, astro-ph 0809.2665v1

• Gardiner L.T. & Noguchi M, 1996,MNRAS, 278,191

• Alcock, C., Allsman, R.A., Alves, D. et al. 1996, MNRAS 280, L49

• Alcock, C. et al. 2001, MNRAS 321, 678.

• Udalski, A., Kubiak, M., & Szymanski, M. 1997, Acta Astron., 47, 319

• Lomb, N. R. 1976, Ap&SS, 39, 447

• Stellingwerf, R. F.1978, ApJ 224, 953S

• Scargle, J. D. 1982, ApJ, 263,835

• Greiner, J. and DiStefano, R. (2002), A&A 387, 944–54

• Ciatti et al., 1981

• Southwell, K.A., Livio, M., Charles, P.A., O’Donoghue, D. and Sutherland, W.J. (1996), ApJ 470, 1065–74