Multi-Anode Microchannel Array Detector Systems Research Articles

Design of a multi-anode microchannel array detector system

The Multi-Anode Microchannel Array (MAMA) is a photon counting detector which utilizes a photocathode for photon to electron conversion, a microchannel plate for signal amplification and a proximity focused anode array for position sensitivity. The detector electronics decode the position of an event through coincidence discrimination. These detectors are designed to provide high spatial and temporal resolution for applications in low-light level imaging and spectroscopy at ultraviolet, FUV and EUV wavelengths. Many space ultraviolet astrophysics missions such as STIS are using MAMA detector systems. Several MAMA detectors have been produced by Nanjing Electronic Devices Institute (Nanjing, China). The development of the MAMA systems based on these detectors is performed by Northwest Institute of Nuclear Technology. In this paper, both the design of the MAMA detector system and the progress of the project are presented.

Design of a multi-anode microchannel array detector system

The Multi-Anode Microchannel Array (MAMA) is a photon counting detector which utilizes a photocathode for photon to electron conversion, a microchannel plate for signal amplification and a proximity focused anode array for position sensitivity. The detector electronics decode the position of an event through coincidence discrimination. These detectors are designed to provide high spatial and temporal resolution for applications in low-light level imaging and spectroscopy at ultraviolet, FUV and EUV wavelengths. Many space ultraviolet astrophysics missions such as STIS are using MAMA detector systems. Several MAMA detectors have been produced by Nanjing Electronic Devices Institute (Nanjing, China). The development of the MAMA systems based on these detectors is performed by Northwest Institute of Nuclear Technology. In this paper, both the design of the MAMA detector system and the progress of the project are presented.

HIRES: a high-resolution stigmatic extreme ultraviolet spectroheliometer for studies of the fine-scale structure of the solar chromosphere, transition region, and corona

We describe the design of a high-resolution stigmatic extremeultraviolet (EUV) spectroheliometer, configured for flight on a Black Brant sounding rocket, which consists of a 45-cm Gregory telescope coupled to a spectrometer employing a single toroidal diffraction grating in a normalincidence Rowland circle mounting and an imaging pulse-counting multianode microchannel array (MAMA) detector system. The toroidal diffraction grating is fabricated by a technique employing an elastically deformable submaster grating that is replicated in a spherical form and then mechanically distorted to produce the desired aspect ratio of the toroidal surface for stigmatic imaging over the selected wavelength range. The spectroheliometer will produce spatially resolved spectra of the chromosphere, transition region, and corona with an angular resolution of 0.4 arcsec or better, a spectral resolution λ/Δλ of about 10 4 in first order, and a temporal resolution of the order of seconds. Because of the geometric fidelity of the MAMA detector system, the spectroheliometer will be able to determine Doppler shifts to a resolution of at least 2 ma at wavelengths near 600 a (~1.0 km s -1 ), depending on the level of the accumulated signal. The unique characteristics of the spectroheliometer will be used in combination with plasma-diagnostic techniques to study the emperature, density, and velocity structures of specific features in the solar outer atmosphere.

Multianode Microchannel Array Detector Systems: Performance Characteristics

Multianode microchannel array detector systems with formats as large as 256 x 1024 pixels are currently under evaluation in the laboratory. Performance data recorded with sealed ultraviolet and visible-light detector tubes have shown that the detector systems have unique characteristics that make them complementary to photoconductive ar-ray detectors, such as charge-coupled devices, and superior to alter-native pulse-counting detector systems employing high-gain microchannel plates.

A search for diffuse band profile variations in the rho Ophiuchi cloud

High signal-to-noise profiles of the broad diffuse interstellar band at 4430 A were obtained on the 2.2-m telescope at the Mauna Kea Observatory, using the newly-developed pulse-counting multi-anode microchannel array detector system in an effort to determine whether the band profile varies with mean grain size as expected if the band is produced by absorbers embedded in grain lattices. The lack of profile variability over several lines of sight where independent evidence indicates that the mean grain size varies shows that lambda 4430 is probably not formed by the same grains that are responsible for interstellar extinction at visible wavelengths. The possibility that this band is created by a population of very small ( approximately 100 A) grains is still viable, as is the hypothesis that it has a molecular origin.