243 citations · 2.3k across the 46 of their papers we have counts for
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Some Aspects of Galactic Cosmic Ray Acceleration
Yousaf Mahmood Butt
I give a synopsis of two aspects of the Galactic Cosmic Ray (GCR) acceleration problem: the importance of the medium energy gamma-ray window, and several specific astrophysical sou…
A Chandra LETGS observation of V4743 Sagittarius: A Super Soft X-ray Source and a Violently Variable Light Curve
J. -U. Ness, S. Starrfield, V. Burwitz +13
V4743 Sgr (Nova Sgr 2002 No. 3) was discovered on 20 September 2002. We obtained a 5ks ACIS-S spectrum in November 2002 and found that the nova was faint in X-rays. We then obtaine…
Cosmic Ray Acceleration by Stellar Associations? The Case of Cygnus OB2
Yousaf Butt, Paula Benaglia, Jorge Combi +10
The origins of all extra-solar cosmic rays -- both the ultra high-energy and lower energy Galactic variety -- remain unclear. It has been argued that the large scale shocks and tur…
Chandra Temperature Map of Abell 754 and Constraints on Thermal Conduction
M. Markevitch, P. Mazzotta, A. Vikhlinin +9
We use Chandra data to derive a detailed gas temperature map of the nearby, hot, merging galaxy cluster A754. Combined with the X-ray and optical images, the map reveals a more com…
CHANDRA/VLA Follow-up of TeV J2032+4131, the Only Unidentified TeV Gamma-ray Source
Yousaf Butt, Paula Benaglia, Jorge Combi +10
The HEGRA Cherenkov telescope array group recently reported a steady and extended unidentified TeV gamma-ray source lying at the outskirts of Cygnus OB2. This is the most massive s…
ULXs, Microblazars, and the Unidentified EGRET sources
Yousaf M. Butt, Gustavo E. Romero, Diego F. Torres
We suggest that ultraluminous X-ray sources (ULXs) and some of the variable low latitude EGRET gamma-ray sources may be two different manifestations of the same underlying phenomen…