Search results for "telescope"
showing 10 items of 499 documents
The wide-field imager for IXO: status and future activities
2010
The Wide Field Imager (WFI) of the International X-ray Observatory (IXO) is an X-ray imaging spectrometer based on a large monolithic DePFET (Depleted P-channel Field Effect Transistor) Active Pixel Sensor. Filling an area of 10 x 10 cm2 with a format of 1024 x 1024 pixels it will cover a field of view of 18 arcmin. The pixel size of 100 x 100 μm2 corresponds to a fivefold oversampling of the telescope's expected 5 arcsec point spread function. The WFI's basic DePFET structure combines the functionalities of sensor and integrated amplifier with nearly Fano-limited energy resolution and high efficiency from 100 eV to 15 keV. The development of dedicated control and amplifier ASICs allows for…
B-MINE, the balloon-borne microcalorimeter nuclear line explorer
2001
B-MINE is a concept for a balloon mission designed to probe the deepest regions of a supernova explosion by detecting Ti-44 emission at 68 keV with spatial and spectral resolutions that are sufficient to determine the extent and velocity distribution of the Ti-44 emitting region. The payload introduces the concept of focusing optics and microcalorimeter spectroscopy to nuclear line emission astrophysics. B-MINE has a thin, plastic foil telescope multilayered to maximize the reflectivity in a 20 keV band centered at 68 keV and a microcalorimeter array optimized for the same energy band. This combination provides a reduced background, an energy resolution of 50 eV and a 3sigma sensitivity in …
Astronomical soft x-ray mirrors reflectivity enhancement by multilayer coatings with carbon overcoating
2004
A number of X-ray astronomical missions of near future will make use of hard X-ray optics with broad-band multilayer coatings. However multilayer mirrors can be also useful to enhance the effective area of a given X-ray telescope in the "classical" low energy X-ray band (0.1 – 10 keV), the window where X-ray spectroscopy provides very useful plasma diagnostics) with a consistent gain with respect to usual single-layer reflectors. Multilayers for soft X-rays are based on stacks with constant d-spacing (in order to minimize the loss due to the photoelectric effect). A further gain in reflectivity (however only restricted to the energy range between 0.5 and 4 keV) can be achieved by using a lo…
Design and optimization of the wide-field spectrometer for EDGE mission
2007
The LOFT mission concept: a status update
2016
The Large Observatory For x-ray Timing (LOFT) is a mission concept which was proposed to ESA as M3 and M4 candidate in the framework of the Cosmic Vision 2015-2025 program. Thanks to the unprecedented combination of effective area and spectral resolution of its main instrument and the uniquely large field of view of its wide field monitor, LOFT will be able to study the behaviour of matter in extreme conditions such as the strong gravitational field in the innermost regions close to black holes and neutron stars and the supra-nuclear densities in the interiors of neutron stars. The science payload is based on a Large Area Detector (LAD, >8m2 effective area, 2-30 keV, 240 eV spectral resolut…
IBIS: The Imager on-board INTEGRAL
2003
The IBIS telescope is the high angular resolution gamma-ray imager on-board the INTEGRAL Observatory, successfully launched from Baikonur (Kazakhstan) the 17th of October 2002. This medium size ESA project, planned for a 2 year mission with possible extension to 5, is devoted to the observation of the gamma-ray sky in the energy range from 3 keV to 10 MeV (Winkler 2001). The IBIS imaging system is based on two independent solid state detector arrays optimised for low ( 15-1000 keV) and high ( 0.175-10.0 MeV) energies surrounded by an active VETO System. This high efficiency shield is essential to minimise the background induced by high energy particles in the highly excentric out of van All…
First observations of the X-ray transient EXO 2030+375 with IBIS/ISGRI
2003
We present a first INTEGRAL observation of the 42s transient X-ray pulsar EXO 2030+375 with IBIS/ISGRI. The source was detected during Cyg X-1 observations in December 2002. We analyzed observations during the outburst period from 9 to 21 December 2002 with a total exposure time of ~770 kiloseconds. EXO 2030+375 was almost always detected during single ~30 minute exposures in the 18-45 energy bands. The source light curve shows the characteristic outburst shape observed in this source.
The 30 Year Search for the Compact Object in SN 1987A
2018
Despite more than 30 years of searches, the compact object in Supernova (SN) 1987A has not yet been detected. We present new limits on the compact object in SN 1987A using millimeter, near-infrared, optical, ultraviolet, and X-ray observations from ALMA, VLT, HST, and Chandra. The limits are approximately 0.1 mJy ($0.1\times 10^{-26}$ erg s$^{-1}$ cm$^{-2}$ Hz$^{-1}$) at 213 GHz, 1 Lsun ($6\times 10^{-29}$ erg s$^{-1}$ cm$^{-2}$ Hz$^{-1}$) in optical if our line-of-sight is free of ejecta dust, and $10^{36}$ erg s$^{-1}$ ($2\times 10^{-30}$ erg s$^{-1}$ cm$^{-2}$ Hz$^{-1}$) in 2-10 keV X-rays. Our X-ray limits are an order of magnitude less constraining than previous limits because we use a…
The rapid atmospheric monitoring system of the Pierre Auger Observatory
2012
The Pierre Auger Observatory is a facility built to detect air showers produced by cosmic rays above 1017 eV. During clear nights with a low illuminated moon fraction, the UV fluorescence light produced by air showers is recorded by optical telescopes at the Observatory. To correct the observations for variations in atmospheric conditions, atmospheric monitoring is performed at regular intervals ranging from several minutes (for cloud identification) to several hours (for aerosol conditions) to several days (for vertical profiles of temperature, pressure, and humidity). In 2009, the monitoring program was upgraded to allow for additional targeted measurements of atmospheric conditions shor…
γ-RAY AND PARSEC-SCALE JET PROPERTIES OF A COMPLETE SAMPLE OF BLAZARS FROM THE MOJAVE PROGRAM
2011
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