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, 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. See also the Be X-ray Binary Monitor project. 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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The giant outburst of EXO 2030+375. II. Broadband spectroscopy and evolution

 R. Ballhausen, P. Thalhammer, P. Pradhan, (...), P. Kretschmar, et al. (A&A 688, A214, 2024) Detailed pulse phase resolved spectroscopy across the outbursts.
The giant outburst of EXO 2030+375 I. Spectral and pulse profile evolution P. Thalhammer, K. Pottschmidt, R. Ballhausen (...), P. Kretschmar, and J. Wilms (A&A 688, A213, 2024) Spectra and pulse profiles showed a stable luminosity dependence during the rise and decline. The pulse profiles show a stark transition at a luminosity of ∼2 × 10^36 erg s^−1, indicating a change in the emission pattern.
An in-depth analysis of the variable cyclotron lines in GX 301-2 N. Zalot, E. Sokolova-Lapa, J. Stierhof, (...), P. Kretschmar, et al. (A&A 686, A95, 2024) In depth study of the cyclotron line features at ~35 and ~52 keV.
VLA monitoring of LS V +44 17 reveals scatter in the X-ray-radio correlation of Be/X-ray binaries J. van den Eijnden, A. Rouco Escorial,  Alfonso-Garzón, J., Miller-Jones, J. C. A., Kretschmar, P., et al. (MNRAS 527, 4260, 2024) Third detection of radio emission from a Be/X-ray binary. X-ray and radio luminosity are correlated, but with different relations for different systems.
Observing the onset of the accretion wake in Vela X-1 C. M. Diez, V. Grinberg, Fürst, F., (...) & P. Kretschmar (A&A 674, A147, 2023) First time onset of wake structures in Vela X-1 are traced in a broad energy band (0.5–78 keV).
Revisiting the archetypical wind accretor Vela X-1 in depth. Case study of a well-known X-ray binary and the limits of our knowledge P. Kretschmar, I. El Mellah, S. Martínez-Núñez, et al. (A&A 652, A95, 2021) Compilation and synthesis of the accumulated knowledge about Vela X-1, both observationally and theoretically.

 

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