Peter Kretschmar

Mission Manager and Astronomer

 

Main Research Fields

Almost all of my research activities are related to accreting X-ray binaries, mostly accreting X-ray pulsars. Using data from various high-energy missions (XMM-Newton, INTEGRAL, NICER, NuSTAR, XRISM, RXTE, Suzaku, Swift and others) my colleagues and I study different aspects of these systems: mechanisms of accretion, period evolution, lightcurves, pulse profiles and spectra. One of my specialties is the study of cyclotron resonant scattering features. Other topics of great interest to me include stellar winds and accretion in HMXB and Be X-ray binary outbursts.  Other fields of interests are X-ray bursts and their feedback on the accretion disk and gamma-ray binaries.


Keywords

  • Accreting X-ray pulsars
  • Stellar winds in HMXB systems
  • Be X-ray binaries
  • Cyclotron line studies, physics of the accretion column
  • Accretion column geometry and pulse profiles
  • Accretion mechanisms
  • X-ray bursts and feedback to accretion

Ongoing collaborations

ISSI Team Meetings

2003 + 2004 Multiwavelength investigation of X-/gamma-ray sources
2007 + 2008 Formation of Cyclotron Lines in Neutron Star Accretion Columns
2011 + 2012 Physics of the Accretion Column of X-ray pulsars
2013 + 2014 Unified View of Stellar Winds in Massive X-ray Binaries
2015 + 2016 Coronae in the X-ray flashlight
2016 + 2017 A Comprehensive View of Stellar Winds in Massive X-ray Binaries
2019 + 2020 Understanding and Unifying the Gamma Rays Emitting Scenarios in High Mass and Low Mass X-Ray Binaries
2021 + 2023 Feeding the spinning top – Spin evolution of accretion-powered pulsars in high-mass X-ray binaries

 

ISSI Working Group

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2024 + 2025 Disentangling Pulse Profiles of (Accreting) Neutron Stars

 

Publications

Recent highlighted papers
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Modeling accretion columns in accretion-powered pulsars:
​​​​​​​I. Accretion column emission and geometry 
II. Directly observable column emission		 S. Falkner, E. Sokolova-Lapa, F-W. Schwarm, (...), P. Kretschmar et al. (A&A 711 A224 & A225, July 2026) Modular framework to model the observed emission from an extended accretion column including detailed spectral and cyclotron line formation as well as relativist ray tracing.
First Look at the High-resolution X-Ray Spectra in the Highly Absorbed High-mass X-Ray Binary IGR J16318−4848 with Chandra  P. Pradhan, D. P. Huenemoerder, B. Paul. (...), P. Kretschmar et al. (ApJ 1004, 215, June 2026) Comprehensive analysis of Chandra HETGS spectra  of this source.
​​​​​​​Energy-resolved pulse profiles of Vela X-1: Cross-calibrating XMM-Newton and NuSTAR to trace spectral features D. K. Maniadakis, A. D'Aì, C. M. Diez, (...) P. Kretschmar et al. (A&A 710, A357, June 2026) Pulsed fraction spectrum as a quantitative cross-calibration diagnostic and as a powerful spectro-timing diagnostic.
The legacy of the INTEGRAL mission J. U. Ness, P. Kretschmar, J. M. Mas-Hesse et al. (Nat. Ast., 10, 612, May 2026) Brief overview of the science done with the INTEGRAL mission.
XMM-Newton Observations of Flares and a Possible Pulse Dropout in the Supergiant X-Ray Binary 4U 1909+07 J. B. Coley, R. Ballhausen, McK Brumback, (...) P. Kretschmar et al. (ApJ 1000, 287, April 2026) Flares and a low phase in two long observations of 4U 1909+07.
The elusive cyclotron line in 4U 1901+03: Hidden, yet present E. Ambrosi, A. D'Aì, G. Cusumano, (...) P. Kretschmar et al. (A&A 709, A42, April 2026)  
Flux variability of the "10 keV feature" of 4U 0115+63 K. Berger, E. Sokolova-Lapa, R. Ballhausen, (...) P. Kretschmar et al. (A&A 707, A365, March 2026) Studying the behaviour of the unexplained "10 keV feature" in a famous Be X-ray binary.
Double-hump spectrum, pulse profile dip, and pulsed fraction spectra from the low-accretion regime in the X-ray pulsar MAXI J0655-013  C. Malacaria, S. N. Pike, A. D'Aì, (...) P. Kretschmar et al. (A&A 706, A321, February 2026) Exploring the timing and spectral properties of MAXI J0655-013 observed in the low-luminosity regime
​​​​​​​Pulse profile variations in the accreting X-ray pulsar Vela X-1 V. Madurga-Favieres, A. Martin-Carrillo, C. M. Diez, (...) P. Kretschmar (A&A, 704, A66, December 2025) Systematic study of pulse profile variations in Vela X-1 down to individual pulse cycles.
First look at Vela X-1 with XRISM C. M. Diez, S. Dupourqué, M. Zhou, (...) P. Kretschmar (A&A, 703, A28, November 2025) First results from an early XRISM observation, coordinated with XMM-Newton and NuSTAR.
Low-frequency spectra of neutron star + OB supergiant binaries: Does wind density drive persistent and flaring modes of accretion? J. van den Eijnden, L. Sidoli, M. Diaz Trigo, (...) P. Kretschmar, et al. (MNRAS 543, 862, October 2025) Observations of the millimeter and radio
emission of binaries where a neutron star accretes from an OB supergiant indicate differences between Supergiant Fast X-ray Transients and other Supergiant X-ray Binaries​​​​​​​. 
SAS in ESA Datalabs: A new platform for XMM-Newton analysis E. G. Gübalhar, C. M. Diez, A. Ibarra, (...) P. Kretschmar (Astronomy and Computing, 53, 100969, October 2025) Implementation of the Science Analysis Software for XMM-Newton in ESA Datalabs.

 

Full list of publications in ADS

Project/mission at ESA

XMM-Newton, previously also INTEGRAL and Hitomi (ASTRO-H)

Member of IAU, EAS, SSAA and SEA
ORCID 0000-0001-9840-2048