X-ray Binaries Research Group

The X-ray Binaries group is active in research in Galactic X-Ray Astronomy, in the fields of binary systems containing a neutron star or a black hole accreting mass from a companion.

A 1 millisecond photograph of an astral bodyLow Mass X-ray Binary

Our interests are in the processes that produce X-ray emission and of the geometry, size and physical conditions in the emission regions, particularly in accretion disc coronae and on the surface of the neutron star, as well as the fundamental physics taking place in sources of widely varying luminosities, including the launching of jets. These aspects are still poorly understood. This work has been carried out using the satellite observatories: Exosat, Rosat, Asca, BeppoSAX, Rossi-XTE, XMM-Newton, Chandra, Suzaku and Swift.



An z-ray of the night skyX-ray Sky from HEAO-1 survey.

The Sky seen in X-rays is filled with binary systems containing neutron stars, black holes and white dwarfs together with X-ray bursters, pulsars, supernova remnants and active galactic nuclei.

The X-ray Binaries are among the brightest sources in the Sky. They consist of a neutron star or black hole in binary orbit with a normal star, in which matter is being transferred gravitationally from the companion star to the compact object releasing huge amount of energy in the X-ray band.

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Group Head



Church M. J., Gibiec A., Balucinska-Church M. 2014,
"Spectral investigations of the nature of the Atoll sources, the Island State and the Atoll Z-track relation",
M.N.R.A.S., 438, 2784-2797.

Spencer R. E., Rushton A. P., Balucinska-Church M., Paragi Z., Schulz N. S., Wilms J., Pooley G. G., Church M. J. 2013,
"Radio and X-ray observations of jet ejection in Cygnus X-2" ,
M.N.R.A.S. (Letters), 435, L48.

Church M. J., Gibiec A., Balucinska-Church M., Jackson N. K. 2012,
"Spectral investigations of the nature of the Scorpius X-1 like sources" ,
Astron. and Astrophys., 546, A35.

Balucinska-Church M., Schulz N. S., Wilms J., Gibiec A., Hanke M., Spencer R. E., Rushton A., Church M. J., 2011,
"Dipping in CygnusX-2 in a multi-wavelength campaign due to absorption of extended ADC emission" ,
Astron. and Astrophys., 530, A102.

Balucinska-Church M., Gibiec A., Jackson N. K., Church M. J., 2010,
"On the nature of the Cygnus X-2 like Z-track sources" ,
Astron. and Astrophys., 512, A9.

Balucinska-Church M., Dotani T., Hirotsu T., Church M. J., 2009,
"Neutral absorber dips in the periodic burster LMXB XB 1323-619 from Suzaku" ,
Astron. and Astrophys., 500, 873-882.

Jackson N. K., Church M. J., Balucinska-Church M., 2009,
"A model for the Z-track phenomenon in GX 5-1 and observational evidence for the physical origins of the kHz QPO" ,
Astron. and Astrophys., 494, 1059-1071.

Church M. J., Jackson N. K., Balucinska-Church M., 2008,
"The importance of radiation pressure in the launching of jets" ,
Chinese Journal of Astronomy and Astrophysics, 8, 191-196.

Balucinska-Church M., Reed D., Church M. J., 2008,
"The periodic bursters XB 1323-619 and GS 1826-24: longterm evolution of the nuclear burning regime and comparison with theory" ,
Chinese Journal of Astronomy and Astrophysics, 8, 319-324.

Church M. J., Halai G. S., Balucinska-Church M., 2006,
``An explanation of the Z-track sources'' ,
Astron. and Astrophys., 460, 233-244.

Church M. J., Reed D., Dotani T., Balucinska-Church M.,Smale A.P. 2005,
``Discovery of absorption features of the ADC and systematic acceleration of the X-ray burst rate in XB1323-619'' ,
M.N.R.A.S., 359, 1136-1344.

Balucinska-Church M., Ostrowski M., Stawarz L., Church M. J., 2005,
``Discovery of hard X-ray features around the hotspots of Cygnus A'' ,
M.N.R.A.S., 357, L6-L10.

Church M. J., Balucinska-Church M., 2004,
``Measurements of accretion disc corona size in LMXB: consequences for Comptonization and LMXB models'' ,
M.N.R.A.S., 348, 955-963.

Balucinska-Church M., Church M. J., Smale A. P., 2004,
``The orbital period of the dipping, bursting, globular cluster X-ray source XB 1746-371 from Rossi-XTE observations'' ,
M.N.R.A.S., 347, 334-338.

Barnard R., Church M. J., Balucinska-Church M., 2003,
``Physical Changes during Z-track Movement in Sco X-1 on the Flaring Branch'' ,
Astron. and Astrophys., 405, 237-248.

Humphrey P. J., Fabbiano G., Elvis M., Church M. J., Balucinska-Church M., 2003,
``Black Hole Binaries and Ultra-Luminous X-ray Source Populations in Normal Galaxies:
a Preliminary Survey with Chandra'' 
M.N.R.A.S., 344, 134-148.

Smale A. P., Church M. J., Balucinska-Church M., 2002,
``A Study of the LMXB XB 1254-690 using Rossi-XTE: X-ray Dipping'' ,
Ap.J., 581, 1286-1292.

Lin X. B., Church M. J., Nagase F., Balucinska-Church M., 2002,
''1SAX J1324.4-6200: a Possible Low Mass Binary Pulsar'' ,
M.N.R.A.S., 337, 1245-1251.

Church M. J., Inogamov N. A., Balucinska-Church M., 2002,
``A comparison of neutron star blackbody luminosities in LMXB with the theory of accretion flow spreading on the stellar surface'' ,
Astron. and Astrophys., 390, 139-146.

Barnard R., Balucinska-Church M., Smale A. P., Church M. J., 2001,
``A Study of the Spectral Evolution during Dipping in XB1323-619 with Rossi-XTE and BeppoSAX'' ,
Astron. and Astrophys., 380, 494-503.

Balucinska-Church M., Barnard R., Church M. J., Smale A. P.,2001,
``Neutron Star Blackbody Contraction during Flaring in X1624-490'' ,
Astron. and Astrophys., 378, 847-860.

Church M. J., Balucinska-Church M., 2001,
``Results of a LMXB survey: Variation in the Height of the Neutron Star Blackbody Emission Region'' ,
Astron. and Astrophys., 369, 915-924.

Church M. J., 2001,
``The Emission Regions in X-Ray Binaries: Dipping as a Diagnostic'' ,
Adv. Space Res., 28 (2-3), 323-335.

Smale A. P., Church M. J., Balucinska-Church M.,2001,
``The Ephemeris and Dipping Spectral Behavior of X1624-490'' ,
Ap.J., 550, 962-969.

Balucinska-Church M., Humphrey P. J., Church M. J., Parmar A. N., 2000,
''A Study of the Dipping LMXB X1624-490 from the braodband BeppoSAX observation'' ,
Astron. and Astrophys., 360, 583-591.

Balucinska-Church M., Church M. J., 2000,
``Discovery of a Red and Blue Shifted Iron Disc Line in the Galactic Jet Source GRO J1655-40'',
M.N.R.A.S., 312, L55-L59.

Balucinska-Church M., Church M. J., Charles P. A., Nagase F., LaSala J., R. Barnard, 2000,
``The Distribution of X-ray Dips with Orbital Phase in Cygnus X-1'',
M.N.R.A.S., 311, 861-868.

Morley R., Church M. J., Smale A. P., Balucinska-Church M., 1999,
``Progressive Covering of the Accretion Disk Corona during Dipping in the LMXB XB 1916-053'',
M.N.R.A.S., 302, 593-598.

Balucinska-Church M., Church M. J., Oosterbroek T., Segreto A., Morley R., Parmar A.N., 1999,
``An X-ray Study of the Dipping Low Mass X-ray Binary XB 1323-619'',
Astron. and Astrophys., 349, 495-504.

LaSala J., Charles P. A., Smith R. A. D., Balucinska-Church M., Church M. J., 1998,
``The Orbital Period of HDE 226868/Cyg X-1'',
M.N.R.A.S., 301, 285-288.

Angelini L., Church M. J., Parmar A. N., Balucinska-Church M., Mineo T., 1998,
``Discovery of a new 170 s X-ray pulsar 1SAX J1324.4-6200'',
Astron. Astrophys., 339, L41-L44.

Church M. J., Parmar A. N., Balucinska-Church M., Oosterbroek T., Dal Fiume D., Orlandini M., 1998,
``Progressive Covering in Dipping and Comptonization in the Spectrum of XB1916-053 from the BeppoSAX observation'',
Astron. Astrophys., 338, 556-562.

Church M. J., Balucinska-Church M., Mitsuda K., Dotani T., Asai K., 1998,
``Progressive Covering of the Accretion Disc Corona during Dipping in the Low-Mass X-ray Binary XBT 0748-676'',
Ap. J., 504, 516-521.

Church M. J., Dotani T., Balucinska-Church M., Mitsuda K., Inoue H., Yoshida K., 1997,
``Simple Photoelectric Absorption during Dipping in the ASCA Observation of XB1916-053'',
Ap. J., 491, 388-394.

Balucinska-Church M., Takahashi T., Ueda Y., Church M. J., Dotani T., Mitsuda K., Inoue H., 1997,
``The Cessation of Flickering during Dipping in Cygnus X-1'',
Ap. J., 480, L115-L119.

Church M. J. and Balucinska-Church M., 1997,
``Attenuation of dipping at low energies in the LMXRB source X1755-338'',
Astron. and Astrophys., 317, L47-L50.

Balucinska-Church M., Church M. J., Maisack M., Belloni T., G. K. Skinner, Staubert R., Doebereiner S. and Englhauser J., 1996,
`` Spectral behaviour of Cygnus X-1 in a broad band 0.1 - 200 keV based on Rosat, TTM and HEXE observations '',
in Multifrequency Behaviour of High Energy Cosmic Sources, ed: F. Giovannelli and L. Sabau-Graziati, Mem. Soc. Astron. Ital., 67, 389-394.

Balucinska-Church M., Belloni T., Church M. J. and Hasinger G., 1995,
``Identification of the soft X-ray excess in Cygnus X-1 with disc emission'',
Astron. and Astrophys., 302, L5-L8.

Church M. J. and Balucinska-Church M., 1995,
``A complex continuum model for the LMXRB dipping sources: application to X1624-49'' ,
Astron. and Astrophys., 300, 441-445.

Church M. J. and Balucinska-Church M., 1993,
``Cosmic Abundance Absorption Dips in X1755-33'',
M.N.R.A.S., 260, 59.