High Energy Results from BeppoSAX

نویسندگان

  • Roberto Fusco-Femiano
  • Mauro Orlandini
  • Sabrina De Grandi
  • Luigina Feretti
  • Paola Grandi
  • Gabriele Giovannini
چکیده

We review all the BeppoSAX results relative to the search for additional nonthermal components in the spectra of clusters of galaxies. In particular, our MECS data analysis of A2199 does not confirm the presence of the nonthermal excess reported by Kaastra et al. (1999). A new observation of A2256 seems to indicate quite definitely that the nonthermal fluxes detected in Coma and A2256 are due to a diffuse nonthermal mechanism involving the intracluster medium. We report marginal evidence (∼ 3σ) for a nonthermal excess in A754 and A119, but the presence of point sources in the field of view of the PDS makes unlikely a diffuse interpretation.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Bepposax/pds Observation of Vela X–1

Vela X–1 has been observed by the Italian/Dutch X–ray satellite BeppoSAX during its Science Verification Phase. During the ∼ 50 ksec observation (orbital phases 0.27–0.34) two different intensity state are present, situation very common in this source. We report results from the pulse phase averaged and pulse phase resolved spectroscopy from the high-energy instrument PDS aboard BeppoSAX.

متن کامل

Initial Results from the High Energy Experiment PDS aboard BeppoSAX

The high energy experiment PDS is one of the Narrow Field Instruments aboard the X–ray astronomy satellite BeppoSAX . It covers the energy band from 15 to 300 keV. Here we report results on its in-flight performance and observations of galactic and extragalactic X–ray sources obtained during the Science Verification Phase of the satellite: in particular Crab, Cen X–3, 4U1626–67 and PKS2155–305.

متن کامل

ar X iv : a st ro - p h / 98 02 07 8 v 1 6 F eb 1 99 8 1 High energy properties of X – ray sources observed with BeppoSAX

We report on highlight results on celestial sources observed in the high energy band (> 20 keV) with BeppoSAX . In particular we review the spectral properties of sources that belong to different classes of objects, i.e., stellar coronae (Algol), supernova remnants (Cas A), low mass X–ray binaries (Cygnus X–2 and the X–ray burster GS1826–238), black hole candidates (Cygnus X–1) and Active Galac...

متن کامل

Bepposax Observations of Centaurus a : the Hard Continuum and the Iron Line Feature

The radio galaxy Centaurus A was observed by the BeppoSAX satellite five times from 1997 to 2000. From July 6 1999 to August 17 1999, the source was also simultaneously pointed by COMPTEL on-board of the γ− ray satellite CGRO. Centaurus A has a complex spectrum with multiple extended components and a strongly absorbed (NH ∼ 10 23 cm) nucleus well fitted by a power law (Γ ∼ 1.8) which bends at h...

متن کامل

BeppoSAX observation of the transient X – ray pulsar GS 1843 + 00

We present the results from both the timing and spectroscopic analysis of the transient X–ray pulsar GS 1843+00 observed by the BeppoSAX satellite on 1997 April 4, when the source was at a luminosity of ∼ 10 erg s. GS 1843+00 shows a very hard spectrum that is well fitted by an absorbed power law (NH ∼ 2.3× 10 cm) modified by a high energy cut–off above 6 keV. The source shows a small pulse amp...

متن کامل

The broad band spectral properties of galactic X–ray binary pulsars

BeppoSAX observed several galactic binary X–ray pulsars during the Science Verification Phase and in the first year of the regular program. The complex emission spectra of these sources are an ideal target for the BeppoSAX instrumentation, that can measure the emission spectra in an unprecedented broad energy band. Using this capability of BeppoSAX a detailed observational work can be done on t...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2002