Results 1 to 10 of about 9,379,945 (304)

Return to the Forgotten Ultraluminous X-Ray Source: A Broadband NICER+NuSTAR Study of NGC 4190 ULX-1

The Astrophysical Journal
We observed the nearby and relatively understudied ultraluminous X-ray source (ULX) NGC 4190 ULX-1 jointly with Neutron Star Interior Composition Explorer (NICER) and NuSTAR to investigate its broadband spectrum, timing properties, and spectral variation
Hannah P. Earnshaw, Matteo Bachetti, Murray Brightman, Felix Fürst, Fiona A. Harrison, Matthew Middleton, Renee Ludlam, Sean N. Pike, Daniel Stern, Dominic J. Walton   +9 more
doaj   +1 more source

Brightening and Fading in the Youngest Galactic Supernova Remnant G1.9+0.3: 13 Years of Monitoring with the Chandra X-Ray Observatory

The Astrophysical Journal
We report 13 years of Chandra monitoring of the youngest Galactic supernova remnant G1.9+0.3, the only remnant known to be increasing in brightness. We confirm the spatially integrated rate of flux increase of (1.2 ± 0.2)% yr ^−1 (1–7 keV), but find ...
Kazimierz J. Borkowski, Stephen P. Reynolds, David A. Green, Robert Petre   +3 more
doaj   +1 more source

Optical Emission from Luminous and Very Soft X-Ray Sources in Nearby Galaxies: Testing the Scenario of Edge-on Supercritical Accretion Systems

The Astrophysical Journal
Supercritical accretion onto compact objects is expected to drive optically thick winds, resulting in observed X-ray emission as a function of viewing angle.
Xiaohong Tang, Hua Feng
doaj   +1 more source

A Precessing Stellar Disk Model for Superorbital Modulations of the Gamma-Ray Binary LS I+61° 303

The Astrophysical Journal
Gamma-ray binary LS I+61° 303 consists of a neutron star orbiting around a Be star with a period of P _orb ≃ 26.5 days. Apart from orbital modulations, the binary shows long-term flux variations with a superorbital period of ${P}_{\sup }\simeq 4.6\,{\rm ...
A. M. Chen, J. Takata, Y. W. Yu
doaj   +1 more source

Neutron Stars as X-ray Sources

Nature, 1964
DURING the rocket flight reported in the preceding communication, Bowyer et al. found two celestial X-ray sources with diameters less than 5°. One was located in the northern part of Scorpius in a region of faint stars but devoid of visible nebulosity and radio objects, while the other was coincident with the Crab Nebula, the well-known source of ...
openaire   +1 more source

Hubble Constant Measurement from Quasiperiodic Eruptions as Electromagnetic Counterparts to Extreme Mass Ratio Inspirals

The Astrophysical Journal
Gravitational waves (GWs) accompanied by electromagnetic counterparts, known as bright sirens, provide a novel methodology to measure the Hubble constant ( H _0 ).
Yejing Zhan, Di Wang, Shuang-Xi Yi, Fa-Yin Wang   +3 more
doaj   +1 more source

Dual-Energy Processing of X-ray Images of Beryl in Muscovite Obtained Using Pulsed X-ray Sources. [PDF]

Sensors (Basel), 2023
Komarskiy A, Korzhenevskiy S, Ponomarev A, Chepusov A.   +3 more
europepmc   +1 more source

Discovery of a Candidate 2 keV Cyclotron Resonance Scattering Feature in the HLX NGC 3583 X-1

The Astrophysical Journal
We present a broadband X-ray study of the transient hyperluminous X-ray source (HLX), 2SXPS J111416.1+481833, in the galaxy NGC 3583, using archival XMM-Newton, NuSTAR, and Chandra data, and long-term Swift X-ray Telescope monitoring.
Kiran M. Jayasurya, Aman Upadhyay, Vikram Rana   +2 more
doaj   +1 more source

Simulation study of a novel small animal FLASH irradiator (SAFI) with integrated inverse-geometry CT based on circularly distributed kV X-ray sources. [PDF]

Sci Rep, 2023
Tan Y, Zhou S, Haefner J, Chen Q, Mazur TR, Darafsheh A, Zhang T.   +6 more
europepmc   +1 more source

X-Ray Polarized View of the Accretion Geometry in the X-Ray Binary Circinus X-1

The Astrophysical Journal Letters
Cir X-1 is a neutron star X-ray binary characterized by strong variations in flux during its eccentric ∼16.6 day orbit. There are also strong variations in the spectral state, and it has historically shown both atoll and Z state properties.
John Rankin, Fabio La Monaca, Alessandro Di Marco, Juri Poutanen, Anna Bobrikova, Vadim Kravtsov, Fabio Muleri, Maura Pilia, Alexandra Veledina, Rob Fender, Philip Kaaret, Dawoon E. Kim, Andrea Marinucci, Herman L. Marshall, Alessandro Papitto, Allyn F. Tennant, Sergey S. Tsygankov, Martin C. Weisskopf, Kinwah Wu, Silvia Zane, Filippo Ambrosino, Ruben Farinelli, Andrea Gnarini, Iván Agudo, Lucio A. Antonelli, Matteo Bachetti, Luca Baldini, Wayne H. Baumgartner, Ronaldo Bellazzini, Stefano Bianchi, Stephen D. Bongiorno, Raffaella Bonino, Alessandro Brez, Niccolò Bucciantini, Fiamma Capitanio, Simone Castellano, Elisabetta Cavazzuti, Chien-Ting Chen, Stefano Ciprini, Enrico Costa, Alessandra De Rosa, Ettore Del Monte, Laura Di Gesu, Niccolò Di Lalla, Immacolata Donnarumma, Victor Doroshenko, Michal Dovčiak, Steven R. Ehlert, Teruaki Enoto, Yuri Evangelista, Sergio Fabiani, Riccardo Ferrazzoli, Javier A. Garcia, Shuichi Gunji, Kiyoshi Hayashida, Jeremy Heyl, Wataru Iwakiri, Svetlana G. Jorstad, Vladimir Karas, Fabian Kislat, Takao Kitaguchi, Jeffery J. Kolodziejczak, Henric Krawczynski, Luca Latronico, Ioannis Liodakis, Simone Maldera, Alberto Manfreda, Frédéric Marin, Alan P. Marscher, Francesco Massaro, Giorgio Matt, Ikuyuki Mitsuishi, Tsunefumi Mizuno, Michela Negro, Chi-Yung Ng, Stephen L. O’Dell, Nicola Omodei, Chiara Oppedisano, George G. Pavlov, Abel L. Peirson, Matteo Perri, Melissa Pesce-Rollins, Pierre-Olivier Petrucci, Andrea Possenti, Simonetta Puccetti, Brian D. Ramsey, Ajay Ratheesh, Oliver J. Roberts, Roger W. Romani, Carmelo Sgrò, Patrick Slane, Paolo Soffitta, Gloria Spandre, Douglas A. Swartz, Toru Tamagawa, Fabrizio Tavecchio, Roberto Taverna, Yuzuru Tawara, Nicholas E. Thomas, Francesco Tombesi, Alessio Trois, Roberto Turolla, Jacco Vink, Fei Xie   +103 more
doaj   +1 more source