Zobrazeno 1 - 10
of 271
pro vyhledávání: '"Hartman, R P"'
The broad-line radio galaxy 3C111 has been suggested as the counterpart of the gamma-ray source 3EGJ0416+3650. While 3C111 meets most of the criteria for a high-probability identification, like a bright flat-spectrum radio core and a blazar-like broa
Externí odkaz:
http://arxiv.org/abs/0808.1740
Autor:
Nandikotkur, Giridhar, Jahoda, Keith M., Hartman, R. C., Mukherjee, R., Sreekumar, P., Böttcher, M., Sambruna, R. M., Swank, Jean H.
Publikováno v:
Astrophys.J.657:706-724,2007
The Energetic Gamma-Ray Experiment Telescope (EGRET) on the Compton Gamma-Ray Observatory (CGRO) discovered gamma-ray emission from more than 67 blazars during its 9 yr lifetime. We conducted an exhaustive search of the EGRET archives and selected al
Externí odkaz:
http://arxiv.org/abs/0704.0939
Autor:
Moiseev, A. A., Hartman, R. C., Ormes, J. F., Thompson, D. J., Amato, M. J., Johnson, T. E., Segal, K. N., Sheppard, D. A.
Publikováno v:
Astropart.Phys.27:339-358,2007
This paper describes the design, fabrication and testing of the Anti-Coincidence Detector (ACD) for the Gamma-ray Large Area Space Telescope (GLAST) Large Area Telescope (LAT). The ACD is LAT first-level defense against the charged cosmic ray backgro
Externí odkaz:
http://arxiv.org/abs/astro-ph/0702581
Autor:
Burnett, T. H., Chekhtman, A., Silva, E. do Couto e, Dubois, R., Flath, D., Gable, I., Grove, J. E., Hartman, R., Kamae, T., Kavelaars, A., Kelly, H., Kotani, T., Kuss, M., Lauben, D., Lindner, T., Lumb, N., Mizuno, T., Moiseev, A., Ozaki, M., Rochester, L. S., Schaefer, R., Spandre, G., Thompson, D. J., Usher, T., Young, K.
Publikováno v:
IEEE Trans.Nucl.Sci.49:1904-1908,2002
The GLAST Balloon Flight Engineering Model (BFEM) represents one of 16 towers that constitute the Large Area Telescope (LAT), a high-energy (>20 MeV) gamma-ray pair-production telescope being built by an international partnership of astrophysicists a
Externí odkaz:
http://arxiv.org/abs/astro-ph/0209595
Autor:
Pian, E., Falomo, R., Hartman, R. C., Maraschi, L., Tavecchio, F., Tornikoski, M., Treves, A., Urry, C. M., Ballo, L., Mukherjee, R., Scarpa, R., Thompson, D. J., Pesce, J. E.
PKS 0537-441, a bright gamma-ray emitting blazar, was observed at radio, optical, UV and X-ray frequencies during various EGRET pointings, often quasi-simultaneously. In 1995 the object was found in an intense emission state at all wavelengths. Beppo
Externí odkaz:
http://arxiv.org/abs/astro-ph/0207355
Autor:
Caraveo, P. A., De Luca, A., La Palombara, N., Mignani, R., Hatziminaoglou, E., Hartman, R., Thompson, D. J., Bignami, G. F.
The limited angular resolution of gamma-ray telescopes prevents the straight identification of the majority of the sources detected so far. While the only certified galactic gamma-ray emitters are associated with pulsars, more than 90% of the nearly
Externí odkaz:
http://arxiv.org/abs/astro-ph/0202479
Day-Scale Variability of 3C 279 and Searches for Correlations in Gamma-Ray, X-Ray, and Optical Bands
Autor:
Hartman, R. C., Villata, M., Balonek, T. J., Bertsch, D. L., Bock, H., Boettcher, M., Carini, M. T., Collmar, W., De Francesco, G., Ferrara, E. C., Heidt, J., Kanbach, G., Katajainen, S., Koskimies, M., Kurtanidze, O. M., Lanteri, L., Lawson, A., Lin, Y. C., Marscher, A. P., McFarland, J. P., McHardy, I. M., Miller, H. R., Nikolashvili, M., Nilsson, K., Noble, J. C., Nucciarelli, G., Ostorero, L., Pursimo, T., Raiteri, C. M., Rekola, R., Savolainen, T., Sillanpaa, A., Smale, A., Sobrito, G., Takalo, L. O., Thompson, D. J., Tosti, G., Wagner, S. J., Wilson, J. W.
Light curves of 3C 279 are presented in optical (R-band), X-rays (RXTE/PCA), and gamma rays (CGRO/EGRET) for 1999 Jan-Feb and 2000 Jan-Mar. During both of those epochs the gamma-ray levels were high, and all three observed bands demonstrated substant
Externí odkaz:
http://arxiv.org/abs/astro-ph/0105247
Autor:
Hartman, R. C., Boettcher, M.
Of the blazars detected by EGRET in GeV gamma rays, 3C 279 is not only the best-observed by EGRET, but also one of the best-monitored at lower frequencies. We have assembled eleven spectra, from GHz radio through GeV gamma rays, from the time interva
Externí odkaz:
http://arxiv.org/abs/astro-ph/0102127
Autor:
Wallace, P. M., Bertsch, D. L., Bloom, S. D., Griffis, N. J., Hartman, R. C., Kniffen, D. A., Thompson, D. J.
The 3rd EGRET Catalog of High-energy Gamma-ray Sources contains 170 unidentified sources, and there is great interest in the nature of these sources. One means of determining source class is the study of flux variability on time scales of days; pulsa
Externí odkaz:
http://arxiv.org/abs/astro-ph/0004252
Autor:
Collmar, W., Benlloch, S., Grove, J. E., Hartman, R. C., Heindl, W. A., Kraus, A., Teraesranta, H., Villata, M., Bennett, K., Bloemen, H., Johnson, W. N., Krichbaum, T. P., Raiteri, C. M., Ryan, J., Sobrito, G., Schoenfelder, V., Williams, O. R., Wilms, J.
We report first observational results of multifrequency campaigns on the prominent Virgo blazars 3C 273 and 3C 279 which were carried out in January and February 1999. Both blazars are detected from radio to gamma-ray energies. We present the measure
Externí odkaz:
http://arxiv.org/abs/astro-ph/0004061