Search results for " X rays"

showing 4 items of 4 documents

The flaring afterglow of GRB 050730

2006

We present a detailed spectral and temporal analysis of Swift and XMM-Newton observations of GRB 050730. The X-ray afterglow of GRB 050730 was found to decline with time with intense flaring activity superimposed. Evidence of flaring activity in the early UVOT optical afterglow, simultaneous with that observed in the X-ray band, was found. Strong spectral evolution in the X-ray energy band during the flaring activity was present.

Afterglows X Rays XMM-Newton Telescope
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FLUXEN portable equipment for direct X-ray spectra measurements

2004

Abstract The proper use of imaging equipment in radiological units is based on an appropriate knowledge of the physical characteristics of the X-ray beam used. The FLUXEN PROJECT is working on a portable apparatus which, together with dedicated software, is able to perform an exact spectral reconstruction of the radiation produced in diagnostic X-ray tubes. The apparatus characterizes the energy spectrum of radiological tubes and also provides a measurement of the emitted flux. The acquisition system is based on a commercial CZT detector (3×3×2 mm 3 ), produced by AMPTEK, cooled by a Peltier cell, with a high efficiency in the diagnostic X-ray energy range and modified in the shaping electr…

PhysicsNuclear and High Energy PhysicsRange (particle radiation)X-ray spectraX ray spectrographs X rays air kerma CZTbusiness.industryRadiationSignalSpectral lineCZTOpticsSoftwareX-ray spectra; direct measurement; CZTElectronicsdirect measurementbusinessInstrumentationBeam (structure)Energy (signal processing)
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Accretion onto Neutron Stars: spectral and timing investigation of Low Mass X-ray Binaries

2021

Settore FIS/05 - Astronomia E Astrofisicaneutron stars X rays X rays binaries accretion accretion disks eclipses ephemerides stars: individual: 4U 1702-429 stars: individual: Scorpius X-1 stars: individual: X 1822-371 stars: individual: GX 17+2
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Long term X-ray spectral variability of the nucleus of M81

2003

We have analysed the soft X-ray emission from the nuclear source of the nearby spiral galaxy M81, using the available data collected with ROSAT, ASCA, BeppoSAX and Chandra. The source flux is highly variable, showing (sometimes dramatic: a factor of 4 in 20 days) variability at different timescales, from 2 days to 4 years, and in particular a steady increase of the flux by a factor of >~ 2 over 4 years, broken by rapid flares. After accounting for the extended component resolved by Chandra, the nuclear soft X-ray spectrum (from ROSAT/PSPC, BeppoSAX/LECS and Chandra data) cannot be fitted well with a single absorbed power-law model. Acceptable fits are obtained adding an extra component, …

PhysicsSolar massSpiral galaxyAstrophysics::High Energy Astrophysical PhenomenaAstrophysics (astro-ph)FluxFOS: Physical sciencesAstronomy and AstrophysicsAstrophysicsRadiusAstrophysics::Cosmology and Extragalactic AstrophysicsAstrophysicsBlack holeRotating black holeSpace and Planetary ScienceROSATX-ray x rays sources ULXsAbsorption (electromagnetic radiation)Astrophysics::Galaxy Astrophysics
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