A Wide Energy Band Compound Pixelated Photon Detector A Wide Energy Band Compound Pixelated Photon Detector Upendra Desai, Larry Orwig Code 682, NASA/GSFC We present a new concept of a stacked detector that provides high spectral resolution over a wide energy band (keV-MeV). ... For the energy range from sub keV to 20 keV we use silicon PIN detectors. To cover energies from 20 keV to 60 keV we use a 2-mm-thick CZT detector beneath the "Si" PIN detector. ...

... NASA's newest Great Observatory, the Chandra X-Ray Observatory (CXO) -- formally known as the Advanced X-Ray Astrophysics Facility (AXAF) -- launched on July 23, 1999 and represents such an advance. ... Hughes Danbury Optical Systems (HDOS), now Raytheon Optical Systems Incorporated, figured and polished the x-ray optics; Optical Coating Laboratory Incorporated (OCLI) coated the polished optics with iridium; and Eastman Kodak Company (EKC) mounted and aligned the optics and provided the optical...

... Instrument tuning )! ... Specific calibrations have been performed recently Standardized high energy Crab spectrum would be very useful JEM-X calibration JEM-X is affected by some instabilities which affect software and calibrations: microstrip erosion ( decreased HV and S/N) microstrip ions diffuse into glass plate ( HV adjustments) gain variation ( electronic efficiency to be determined on short time scales) memory effect on microstrips transient hot spots Observations are ...

The beam pattern and the polarization characteristics . of the radio telescope RATAN-600 . The Mueller matrix elements was computed via formulas [1]: . ... The BP were computed by the aperture method, proceeding from the fild distribution in the aperture of the primary mirror. The components of the main and cross-polarization components of the electric field in the vertical aperture of the primary mirror was computed in Frenel diffraction approximation. ...

To main of Laboratory . The research work and design of optical and optical-electronic devices are carries out by laboratory staff: . ... Lens: . ... In the layout 1 prism systems perform functions of dispersive element, corrector of aberrations, optical reducer. ... Spectral range 200 - 400 nm; . ... Back Forward . ... The main corrector's function are compensation of field aberrations of the main spherical mirror of a telescope (diameter of 600 mm, f'=1200 mm) and increase aperture ratio. ...

... ATNF Home . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Australia Telescope User Committee . ... Astrophysics graduate student programs . ... Facilities . ATNF facilities . ... Australian Square Kilometre Array Pathfinder . Murchison Radio-astronomy Observatory . ... Parkes radio telescope . Australia Telescope Compact Array . ... Visiting Parkes radio telescope . Visiting Australia Telescope Compact Array . ... Parkes radio telescope webcam . ...

. Diameter of circular antenna . 576 m . Number of antenna elements . 895 . Size of an element . 11.4 x 2 m . Geometrical area . 15000 m 2 . Effective area of full circle . 3500 m 2 . Wavelength range . 1 - 50 cm . Frequency range . 610 - 30000 MHz . Maximum angular resolution . 2 arcsec . Accuracy of coordinate determination . 1-10 arcsec . Flux density limit . 0.500 mJy . Absolute brightness temperature limit . 0.050 mK . Tracking time (South sector + Flat mirror) . 1-3 h . [RATAN-600 Homepage]

Direct Electron Imaging Using Back Thinned CCDs . ... Figure 5. Measured CTF for GaAs SI502AB EBCCD for various acceleration energies @ 1*10 -4 footcandles faceplate illumination using a 590 nanometer wavelength source. ... Contrast transfer function was measured on both EBCCD tubes as a function of both acceleration voltage and light level. ... A difference frame of two identical flat field frames at a 'high' light level was used for the measurement of variance versus mean in the EBCCD tube. ...

... We are developing and integrating software to simulate the focal plane detectors, shutters, and gratings for the Advanced X-ray Astrophysical Facility (AXAF). ... The simulations are currently being used for planning calibration activities, on-orbit performance prediction and for testing the analysis and telemetry software. ... The models, being developed as part of the AXAF Science Center, are being used to aid in calibration planning and to characterize the performance of the AXAF observatory. ...

... The accuracy of calculation of both INTERBALL spacecraft (SC) motion has been estimated at the IKI. ... The 30 days measuring intervals were used during the Tail probe (TP) orbital data treatment, and 15 days intervals - during the Auroral probe (AP) orbit determination. ... http://www.iki.rssi.ru/vprokhor/indap.htm for the Auroral probe; . http://www.iki.rssi.ru/vprokhor/indtp.htm for the Tail probe . ... http://www.iki.rssi.ru/vprokhor/ssc.htm , or http://www.iki.rssi.ru/vprokhor/amisan.htm . ...

function chanarf, rmfstr , effar , spec = spec , chnrg = chnrg ,verbose=verbose, _extra=e ;+ ;function chanarf ; compute the average effective area over each channel, as a ; weighted average of ... difference mainly for low and medium spectral ; resolution data. for high-res grating data, not so much. ; ;syntax ; carf=chanarf( rmfstr , effar , spec = spec ) ; ;parameters ; ...