Results 41 to 50 of about 195 (150)

Unlocking the nature of ultraluminous X‐ray sources using their X‐ray spectra [PDF]

Astronomische Nachrichten, 2011
AbstractWe explore the nature of ultraluminous X‐ray sources through detailed investigations of their spectral shape using some of the highest quality data available in the XMM‐Newton public archives. Phenomenological models allow us to characterise their spectra, while more ‘physically‐motivated’ models enable us to explore the physical processes ...
Gladstone, J.C., Roberts, T.P., Done, C.
openaire   +3 more sources

The ultraluminous X-ray source bubble in NGC 5585 [PDF]

Monthly Notices of the Royal Astronomical Society, 2020
ABSTRACT Some ultraluminous X-ray sources (ULXs) are surrounded by collisionally ionized bubbles, larger and more energetic than supernova remnants: they are evidence of the powerful outflows associated with super-Eddington X-ray sources.
R Soria, M W Pakull, C Motch, J C A Miller-Jones, A D Schwope, R T Urquhart, M S Ryan   +6 more
openaire   +4 more sources

Modeling the Emission and Polarization Properties of Pulsating Ultraluminous X‐Ray Sources

Astronomische Nachrichten, Volume 346, Issue 1, January 2025.
ABSTRACT Pulsating Ultraluminous X‐ray Sources (PULXs) are a class of extragalactic sources with high X‐ray luminosity, in excess of 1039$$ {10}^{39} $$ erg s−1$$ {\mathrm{s}}^{-1} $$, and showing pulsations that associate them with neutron stars accreting at a super‐Eddington rate.
S. Conforti, L. Zampieri, R. Taverna, R. Turolla, N. Brice, F. Pintore, G. L. Israel   +6 more
wiley   +1 more source

Probing extreme black‐hole outflows on short timescales via high spectral‐resolution x‐ray imagers

Astronomische Nachrichten, Volume 345, Issue 6-7, July-August 2024.
Abstract We investigate outflows and the physics of super‐Eddington versus sub‐Eddington regimes in black hole systems. Our focus is on prospective science using next‐generation high‐resolution soft x‐ray instruments. We highlight the properties of black hole ultraluminous x‐ray source (ULX) systems in particular. Owing to scale invariance in accreting
C. Pinto, J. F. Steiner, A. Bodaghee, P. Chakraborty, M. Sobolewska, D. R. Pasham, A. Ogorzalek, J. Zuhone, A. Bogdan, M. Vogelsberger   +9 more
wiley   +1 more source

Spectroscopy of optical counterparts of ultraluminous X-ray sources [PDF]

Astrophysical Bulletin, 2007
submitted to Astrophysical Bulletin (Bull. Special Astrophys. Obs.)
Abolmasov, P., Fabrika, S., Sholukhova, O., Afanasiev, V.   +3 more
openaire   +2 more sources

Chemical Evolution of the Universe and its Consequences for Gravitational‐Wave Astrophysics

Annalen der Physik, Volume 536, Issue 2, February 2024.
Population properties of double compact object mergers (especially binary black holes) are sensitive to the metallicity dependent cosmic star formation history. The uncertainty of this quantity cannot be ignored and makes the interpretation of current gravitational wave observations difficult.
Martyna Chruślińska
wiley   +1 more source

A Study of Spectral Variability Between Flaring and Nonflaring State in M74 X-1

The Astrophysical Journal
We conducted an extensive long-term spectral and timing study of the ultraluminous X-ray (ULX) source M74 X-1, using data taken between 2001 and 2021 by Chandra and XMM-Newton X-ray observatories.
Aman Upadhyay, Tanuman Ghosh, Vikram Rana   +2 more
doaj   +1 more source

Compact radio emission in Ultraluminous X‐ray sources [PDF]

Astronomische Nachrichten, 2011
AbstractWe present results from our studies of radio emission from selected Ultraluminous X‐ray (ULX) sources, using archival Giant Metrewave Radio Telescope (GMRT) data and new European VLBI Network (EVN) observations. The GMRT data are used to find possible faint radio emission from ULX sources located in late‐type galaxies in the Chandra Deep Fields.
Mezcua, M., Lobanov, A. P.
openaire   +2 more sources

The Ultraluminous X-Ray Sources Population of the Galaxy NGC 7456 [PDF]

The Astrophysical Journal, 2020
Abstract Ultraluminous X-ray sources (ULXs) are a class of accreting compact objects with X-ray luminosities above 1039 erg s−1. The ULX population counts several hundred objects but only a fraction are well studied. Here we present a detailed analysis of all ULXs hosted in the galaxy NGC 7456.
F. Pintore, M. Marelli, R. Salvaterra, G. L. Israel, G. A. Rodríguez Castillo, P. Esposito, A. Belfiore, A. De Luca, A. Wolter, S. Mereghetti, L. Stella, M. Rigoselli, H. P. Earnshaw, C. Pinto, T. P. Roberts, D. J. Walton, F. Bernardini, F. Haberl, C. Salvaggio, A. Tiengo, L. Zampieri, M. Bachetti, M. Brightman, P. Casella, D. D’Agostino, S. Dall’Osso, F. Fürst, F. A. Harrison, M. Mapelli, A. Papitto, M. Middleton   +30 more
openaire   +9 more sources

Discovery of a 9.67 s Pulsar in an Ultraluminous X-Ray Source in NGC 4631 with XMM-Newton

The Astrophysical Journal Letters
Thanks to a recent observation with XMM-Newton, we discovered periodic pulsations at P  = 9.6652 ± 0.0002 s in a new ultraluminous X-ray source (ULX) in the galaxy NGC 4631. This source, dubbed as X−8, shows one of the largest spin-up rates ever observed,
Lorenzo Ducci, Sandro Mereghetti, Fabio Pintore, Sinan Allak, Andrea Santangelo, Manami Sasaki, Patrick Kavanagh   +6 more
doaj   +1 more source