Results 81 to 90 of about 2,330,942 (208)

The Chandra X-Ray Observatory [PDF]

, 2006
We present here an overview of the status of the Chandra X-ray Observatory which has nowbeen operating forfive years.The Observatory is running smoothly, and the scientific return continues to be outstanding. We provide some details on the molecular contamination of the ACIS fillters and its impact on observations.
openaire   +1 more source

Phase-resolved Deadtime of the Crab Pulsar Using IXPE Data

The Astrophysical Journal
After receiving an X-ray photon, an X-ray detector is not operational for a duration known as deadtime. It is detector specific and its effect on the data depends upon the luminosity of the source.
M. Vivekanand
doaj   +1 more source

Challenging the Forward Shock Model with the 80 Ms Follow up of the X-ray Afterglow of Gamma-Ray Burst 130427A

Galaxies, 2017
GRB 130427A was the most luminous gamma-ray burst detected in the last 30 years. With an isotropic energy output of 8.5 × 10 53 erg and redshift of 0.34, it combined very high energetics with a relative proximity to Earth in an unprecedented ...
Massimiliano De Pasquale, Mathew Page, David Alexander Kann, Samantha R. Oates, Steve Schulze, Bing Zhang, Zach Cano, Bruce Gendre, Daniele Malesani, Andrea Rossi, Neil Gehrels, Eleonora Troja, Luigi Piro, Michel Boër, Giulia Stratta   +14 more
doaj   +1 more source

A uniform X-ray analysis of 79 distant galaxy clusters with ROSAT and ASCA [PDF]

, 2004
We present a uniform analysis of the ROSAT HRI and the ASCA GIS/SIS data for 79 distant clusters of galaxies in the redshift range 0.1 < z < 0.82 to study the global structures of the intracluster medium.
N. Ota, K. Mitsuda
semanticscholar   +1 more source

PHOTOMETRIC STUDY OF A NEW X-RAY SOURCE -THE ECLIPSING POLAR RXJ 2107.9-0518

Odessa Astronomical Publications, 2017
The object RXJ 2107.9-0518 was discovered as a soft X-ray source at the space observatory ROSAT in 1990. Its X-ray spectrum is characteristic to the systems of the AM Her type thus the object was suspected to be a polar.
E. P. Pavlenko
doaj   +1 more source

XTE J1739–302 as a Supergiant Fast X-Ray Transient [PDF]

, 2005
XTE J1739-302 is a transient X-ray source with unusually short outbursts, lasting on the order of hours. Here we give a summary of X-ray observations we have made of this object in outburst with the Rossi X-Ray Timing Explorer (RXTE) and at a low level ...
David M. Smith, W. Heindl, C. Markwardt, J. Swank, I. Negueruela, Thomas E. Harrison, L. Huss   +6 more
semanticscholar   +1 more source

Mildly Super-Eddington Accretion onto Slowly Spinning Black Holes Explains the X-Ray Weakness of the Little Red Dots

The Astrophysical Journal
JWST has revealed a population of low-luminosity active galactic nuclei at z > 4 in compact, red hosts (the “Little Red Dots,” or LRDs), which are largely undetected in X-rays.
Fabio Pacucci, Ramesh Narayan
doaj   +1 more source

Unveiling the Nature of Superorbital Modulation of SMC X-1 Using NinjaSat

The Astrophysical Journal
We report a long-term, high-cadence timing and spectral observation of the X-ray pulsar SMC X-1 using NinjaSat—a 6U CubeSat in low-Earth orbit—covering nearly a full superorbital cycle.
Chin-Ping Hu, Naoyuki Ota, Takuya Takahashi, Tomoshi Takeda, Teruaki Enoto, Toru Tamagawa, Biswajit Paul, Sota Watanabe, Wataru Iwakiri, Tatehiro Mihara, Amira Aoyama, Satoko Iwata, Kaede Yamasaki, Takayuki Kita, Soma Tsuchiya, Mayu Ichibakase, (NinjaSat collaboration)   +16 more
doaj   +1 more source

Resident Archive Services of the Yohkoh Legacy Data Archive

Data Science Journal, 2009
The Yohkoh Legacy Data Archive (YLA) is one of the first group of Resident Archives (RAs) selected for funding for NASA's Virtual Observatories for the Heliophysics Data program.
A Takeda, L Acton, D McKenzie, K Yoshimura, S Freeland   +4 more
doaj   +1 more source

Athena+: The first Deep Universe X-ray Observatory

, 2013
The Advanced Telescope for High-energy Astrophysics (Athena+) is being proposed to ESA as the L2 mission (for a launch in 2028) and is specifically designed to answer two of the most pressing questions for astrophysics in the forthcoming decade: How did ordinary matter assemble into the large scale structures we see today?
Barret, D., Nandra, K., Barcons, X., Fabian, A., den Herder, J., Piro, L., Watson, M., Aird, J., Branduardi-Raymont, G., Cappi, M., Carrera, F., Comastri, A., Costantini, E., Croston, J., Decourchelle, A., Done, C., Dovciak, M., Ettori, S., Finoguenov, A., Georgakakis, A., Jonker, P., Kaastra, J., Matt, G., Motch, C., O'Brien, P., Pareschi, G., Pointecouteau, E., Pratt, G., Rauw, G., Reiprich, T., Sanders, J., Sciortino, S., Willingale, R., Wilms, J.   +33 more
openaire   +4 more sources