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Performance characterization of uv science cameras developed for the chromospheric lyman-alpha spectro-polarimeter
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Stewart, Mike Robertson, Bryan Cirtain, Jonathan Winebarger, Amy Beabout, Dyana Kobayashi, Ken Hyde, David Beabout, Brent Champey, Patrick |
| Copyright Year | 2014 |
| Description | The NASA Marshall Space Flight Center (MSFC) has developed a science camera suitable for sub-orbital missions for observations in the UV, EUV and soft X-ray. Six cameras will be built and tested for flight with the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP), a joint National Astronomical Observatory of Japan (NAOJ) and MSFC sounding rocket mission. The goal of the CLASP mission is to observe the scattering polarization in Lyman-alpha and to detect the Hanle effect in the line core. Due to the nature of Lyman-alpha polarization in the chromosphere, strict measurement sensitivity requirements are imposed on the CLASP polarimeter and spectrograph systems; science requirements for polarization measurements of Q/I and U/I are 0.1 percent in the line core. CLASP is a dual-beam spectro- polarimeter, which uses a continuously rotating waveplate as a polarization modulator, while the waveplate motor driver outputs trigger pulses to synchronize the exposures. The CCDs are operated in frame-transfer mode; the trigger pulse initiates the frame transfer, effectively ending the ongoing exposure and starting the next. The strict requirement of 0.1 percent polarization accuracy is met by using frame-transfer cameras to maximize the duty cycle in order to minimize photon noise. Coating the e2v CCD57-10 512x512 detectors with Lumogen-E coating allows for a relatively high (30 percent) quantum efficiency at the Lyman-alpha line. The CLASP cameras were designed to operate with a gain of 2.0 +/- 0.5, less than or equal to 25 e- readout noise, less than or equal to 10 e-/second/pixel dark current, and less than 0.1percent residual non-linearity. We present the results of the performance characterization study performed on the CLASP prototype camera; system gain, dark current, read noise, and residual non-linearity. |
| File Size | 74762 |
| Page Count | 1 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20140011800 |
| Archival Resource Key | ark:/13960/t54f6sj39 |
| Language | English |
| Publisher Date | 2014-06-13 |
| Access Restriction | Open |
| Subject Keyword | Chromosphere Lyman Alpha Radiation Polarimeters Japan Scattering Sounding Rockets Ultraviolet Radiation Sensitivity Ccd Cameras X Rays Linearity Prototypes Dark Current Extreme Ultraviolet Radiation Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
