Dr Hab. Monika Balucinska-Church MSc, PhD, Dr Hab.

School of Physics and Astronomy
Honorary Senior Research Fellow

Contact details

School of Physics and Astronomy
University of Birmingham
B15 2TT

Monika Balucinska-Church is an X-ray Astronomer working at the international level specialising in X-ray Binaries, the binary systems containing a black hole or a neutron star accreting mass from a companion star.

Starting from the position that the sources of X-rays in these systems were poorly understood, she has used observations of the major phenomena including X-ray absorption to establish the geometry, size and physical conditions in the emitting regions (the accretion disc coronae and the surface of the neutron star) leading to a Unified Model which can explain X-ray Binaries in general.

This has encouraged collaborations with leading institutes in Japan, Germany, the Netherlands and the USA.

The work has been supported by the Royal Society, the British Council, the UK research councils and the Polish
Ministry of Science. She is a referee for all the major astrophysical journals.


• Member of International Astronomical Union
• DSc, Jagiellonian University
• PhD in Astronomy, Polish Academy of Sciences
• Member of the Polish Astronomical Society
• MSc in Astronomy, Jagiellonian University


Monika Balucinska-Church gained an MSc in Astronomy from the Jagiellonian University, Cracow, and a PhD from the Copernicus Centre, Polish Academy of Sciences, Warsaw, based on her co-discovery of the soft X-ray emission excess in the black hole Cygnus X-1. She then worked in a post-doctoral position at the Max-Planck-Insititut fuer Extraterrestrische Physik in Garching, Germany in the X-ray Astronomy group. In the University of Birmingham she formed part of the nucleus of the X-ray Binaries group. She has collaborated with X-ray astronomers in Japan, the United States, Germany, Netherlands and Italy working on X-ray Binaries using all of the major satellite-borne X-ray observatories. She spent an extensive period working in the Institute of Space and Astronautical Science (ISAS), Japan supported by the Royal Society and the British Council, and shorter spells at the European Space Agency in the Netherlands and the Goddard Space Flight Center, NASA in the USA. While at the University of Birmingham she was appointed for 10 years in her Alma Mater as associate professor at the Astronomical Observatory in Cracow. Here she continued research and supervised MSc and PhD students. During that period, she received her Habilitation in Physics (DSc) from the Jagiellonian University based on 10 selected publications. She was also co-supervisor of numbers of PhD students in the X-ray Binaries group at Birmingham.

Postgraduate supervision

She supervised MSc and PhD students at the Jagiellonian University and co-supervised PhD students at University of Birmingham.


Her research focussed in 1990-2000 on the study of the dipping low mass X-ray binary sources as a method of resolving the major controversy on the origin of X-ray emission in Galactic binary X-ray sources. The obscuration of the X-ray sources by matter in the outer accretion disc allowed the X-rays to be identified unambiguously with hard X-rays from a radially extended hot corona above the disk plus thermal emission from the neutron star. This resolved a controversy that had existed for 25 years substantially impeding progress.

Based on this success, research expanded to all classes of X-ray binary, specifically the so-called Z-sources, the hugely luminous objects emitting X-rays at the theoretical maximum. Adoption of the emission model led to an explanation of the complicated behaviour of these sources. Finally, the approach was extended to the faint binaries or Atoll sources and the ability to explain all classes of sources produced the recently-published Unified Model of Low Mass X-ray Binaries by the Birmingham group.

The consequences of this unified model are now being investigated in a number of areas. Firstly, an important feature of the model is the very strong radiation pressure of the neutron star under certain conditions which physically must lead to disruption of the nearby accretion disc. Investigation of the relativistic jets present in these sources has been seen to take place under these conditions. This indicates a solution of the major astrophysical problem of jet formation, showing this takes place by radiation pressure. Radio and X-ray observations of Cygnus X-2 in collaboration with colleagues at Jodrell Bank, MIT and Germany are revealing the conditions of jet formation.

Radiation pressure can also be high when emission is from a narrow equatorial region of the neutron star and so the size of the emitting region is important as jets may be formed.

Investigations are taking place of the size of the X-ray emitting parts of the neutron star, this varying from an equatorial strip metres high, to the full height of the star. There is substantial evidence that this variation is explained by the leading theoreticians in terms of the impact of accreting material upon the surface of the neutron star, and this subject is fundamental to the understanding of the X-ray emission from binary sources.


Selected publications:

Balucinska M., Hasinger G., 1991, ``Exosat ME Observations of Cygnus X-1: Study of the Soft X-ray Excess'', A&A, 241, 439-450.

Balucinska-Church M.,  McCammon D., 1992, ``Photoelectric Absorption Cross-Sections with Variable Abundances'', ApJ, 400, 699-700.

Church M. J., Balucinska-Church M., 1993, ``Cosmic  Abundance Absorption Dips in X1755-33'', MNRAS, 260, 59-66.

Church M. J., Balucinska-Church M., 1995, ``A Complex Continuum Model for the LMXB Dipping Sources: Application to X1624-490'',  A&A, 300, 441-445.

Balucinska-Church M., Belloni T., Church M. J., Hasinger G., 1995, ``Identification of the Soft X-ray Excess in Cygnus X-1 with Disc Emission'',  A&A, 302, L5-L8.

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'', ApJ,  480, L115 L119.

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'', ApJ, 491, 388-394.

Church M. J., Balucinska-Church M., Mitsuda K., Dotani T., Asai K., 1998, ``Spectral Evolution during Dipping in LMXB XBT 0748-676 from the ASCA PV Phase Observation'',  ApJ, 504, 516-521.

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'', A&A,  338, 556-562.

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'', A&A, 339, L41-L44.

LaSala J., Charles P. A., Smith R. A. D., Balucinska-Church M., Church M. J., 1998, ``The Orbital Period of HDE226868/Cygnus X-1'', MNRAS, 301, L285-L288.

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  XB1323-619'', A&A, 349, 495-504.

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

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'',  MNRAS, 312, L55-L59.

Balucinska-Church M., Humphrey P. J., Church M. J.,   Parmar A. N., 2000, ``A Study of the Dipping Low Mass X-ray Binary X1624-490 from the Broadband BeppoSAX Observation'', A&A, 360, 583-591.

Church M. J.,  Balucinska-Church M., 2001, ``Results of a LMXB Survey: Variation in the Height of the Neutron Star Blackbody Emission Region'', A&A,   369, 915-924.

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

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

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

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'', A&A, 390, 139-146.

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

Smale A. P., Church M. J., Balucinska-Church M., 2002, ``Dip Spectroscopy of the Low Mass X-ray Binary XB 1254-690'',  ApJ, 581, 1286-1292.

Barnard R., Church M. J., Balucinska-Church M., 2003, ``Physical Changes during Z-track Movement in Sco X-1 on the Flaring Branch'', A&A, 405, 237-247.

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'', MNRAS, 344, 134-148.

Balucinska-Church M., Church M. J., Smale A. P., 2004, ``The Orbital Period of the Dipping, Bursting, Globular Cluster X- ray Source XB1746-371 from Rossi-XTE Observations'', MNRAS, 347, 334-338.

Church M. J., Balucinska-Church M., 2004, ``Measurements of Accretion Disc Corona Size in LMXB: Consequences for Comptonization and LMXB Models'', MNRAS, 348, 955-963.

Balucinska-Church M., Ostrowski M., Stawarz L., Church M. J., 2005, ``Discovery of Hard X-ray Features around the Hotspots of Cygnus A'', MNRAS, 357, L6-L10.

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'', MNRAS, 359, 1336-1344.

Church M. J., Halai G., Balucinska-Church M., 2006, ``An Explanation of the Z-track Sources'', A&A, 460, 233-244.

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'', A&A, 494, 1059-1071. 

Balucinska-Church M., Dotani T., Hirotsu T., Church M. J., 2009, ``Neutral Absorber Dips in the Periodic Burster LMXB XB 1323-619 from Suzaku'', A&A, 500, 873-882.

Balucinska-Church M., Gibiec A., Jackson N. K.,  Church  M. J., 2010, ``On the Nature of the Cygnus X-2 like Z-track Sources'', A&A, 512, A9.

Balucinska-Church M., Schulz N. S.,  Wilms J., Gibiec A., Hanke M., Spencer R. E., Rushton A., Church M. J., 2011, ``Dipping in Cygnus X-2 in a Multi-wavelength Campaign due to Absorption of Extended ADC Emission'', A&A, 530, A102.

Church M. J., Gibiec A., Balucinska-Church M., Jackson  N. K., 2012, ``Spectral Investigations of the Nature of the Sco X-1 like Sources'', A&A, 546, A35.

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'', MNRAS, 435, L48-L52.

Church, M. J., Gibiec, A., Balucinska-Church M., 2014,``The Nature of the Island and Banana States in Atoll Sources and a Unified Model for Low-mass X-ray Binaries'', MNRAS, 438, 2784-2797.