73 research outputs found
Optical measurements of atmospheric particles from airborne platforms: in situ and remote sensing instruments for balloons and aircrafts
Multiwavelength laser backscattersondes (MAS) have been widely used from a variety of airborne platforms for
in situ measurements of optical properties of clouds and atmospheric particulate as well as their phase and composition.
Recently, a new miniaturized LIDAR (MULID) has been developed using state-of-art technology for
balloon borne profiling of the same quantities. A description of the two instruments, a survey of preliminary results
obtained during test flights and indications for future use are given
ALMA band 2+3 (67-116 GHz) optics: Design and first measurements
The ALMA telescope is one of the largest on-ground astronomical projects in the world. It has been producing great scientific results since the beginning of operations in 2011. Of all the originally planned bands, band 2 (67-90 GHz) is the last band to be implemented into the array. Recent technological progress has open the possibility to combine bands 2 and 3 (84-116 GHz) into a single wideband receiver. This paper describes the first efforts to design wideband optics which cover both bands, from 67 to 116 GHz, using a profiled corrugated horn and a modified Fresnel lens. First measurements were performed at ESO in Dec15-Jan16 and showed good agreement with simulations
Design, construction, and test of the Gas Pixel Detectors for the IXPE mission
Due to be launched in late 2021, the Imaging X-Ray Polarimetry Explorer
(IXPE) is a NASA Small Explorer mission designed to perform polarization
measurements in the 2-8 keV band, complemented with imaging, spectroscopy and
timing capabilities. At the heart of the focal plane is a set of three
polarization-sensitive Gas Pixel Detectors (GPD), each based on a custom ASIC
acting as a charge-collecting anode. In this paper we shall review the design,
manufacturing, and test of the IXPE focal-plane detectors, with particular
emphasis on the connection between the science drivers, the performance metrics
and the operational aspects. We shall present a thorough characterization of
the GPDs in terms of effective noise, trigger efficiency, dead time, uniformity
of response, and spectral and polarimetric performance. In addition, we shall
discuss in detail a number of instrumental effects that are relevant for
high-level science analysis -- particularly as far as the response to
unpolarized radiation and the stability in time are concerned.Comment: To be published in Astroparticle Physic
Correction to: SERENA: Particle Instrument Suite for Determining the Sun-Mercury Interaction from BepiColombo
International audienc
SERENA:Particle Instrument Suite for Determining the Sun-Mercury Interaction from BepiColombo
International audienceThe ESA-JAXA BepiColombo mission to Mercury will provide simultaneous measurements from two spacecraft, offering an unprecedented opportunity to investigate magnetospheric and exospheric particle dynamics at Mercury as well as their interactions with solar wind, solar radiation, and interplanetary dust. The particle instrument suite SERENA (Search for Exospheric Refilling and Emitted Natural Abundances) is flying in space on-board the BepiColombo Mercury Planetary Orbiter (MPO) and is the only instrument for ion and neutral particle detection aboard the MPO. It comprises four independent sensors: ELENA for neutral particle flow detection, Strofio for neutral gas detection, PICAM for planetary ions observations, and MIPA, mostly for solar wind ion measurements. SERENA is managed by a System Control Unit located inside the ELENA box. In the present paper the scientific goals of this suite are described, and then the four units are detailed, as well as their major features and calibration results. Finally, the SERENA operational activities are shown during the orbital path around Mercury, with also some reference to the activities planned during the long cruise phase
The Imaging X-ray Polarimetry Explorer (IXPE): Technical Overview
The Imaging X-ray Polarimetry Explorer (IXPE) will expand the information space for study of cosmic sources, by adding linear polarization to the properties (time, energy, and position) observed in x-ray astronomy. Selected in 2017 January as a NASA Astrophysics Small Explorer (SMEX) mission, IXPE will be launched into an equatorial orbit in 2021. The IXPE mission will provide scientifically meaningful measurements of the x-ray polarization of a few dozen sources in the 2-8 keV band, including polarization maps of several x-ray-bright extended sources and phase-resolved polarimetry of many bright pulsating x-ray sources
- âŠ