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The Focusing Optics X-ray Solar Imager (FOXSI): Update & Second Launch Project

Metadata Updated: December 6, 2023

<p> Particle acceleration in solar flares and its contribution to coronal heating are among the main&nbsp; unsolved problems in heliophysics. Accelerated electrons in a plasma radiate hard X-ray (HXR)&nbsp; emission through the well-known process of bremsstrahlung. HXR observations therefore are a&nbsp; powerful diagnostic tool, providing quantitative measurements of flare-accelerated electrons. Since&nbsp; bremsstrahlung emission depends on the density of the ambient medium, solar HXR emission is&nbsp; usually brightest from below the transition region, where the density increases rapidly towards the&nbsp; photosphere. Electron beams entering the chromosphere lose energy quickly through collisions and&nbsp; produce relatively intense HXR emission at the footpoints of magnetic field lines. Electron beams&nbsp; moving in the relatively tenuous corona suffer very few collisions, losing little energy and producing&nbsp; only faint HXR emission. Present-day HXR instrumentation does not have the sensitivity to see&nbsp; faint HXR emission from electrons traveling in the corona, nor the dynamic range to see such&nbsp; faint emission in the presence of bright HXR footpoint emission in the chromosphere. Existing&nbsp; observations therefore show us only where energetic electrons are stopped, but not where they&nbsp; are accelerated, nor along what path they escape from the acceleration site. The most sensitive&nbsp; solar HXR observations so far are provided by the Reuven Ramaty High Energy Spectroscopic&nbsp; Imager (RHESSI) (Lin et al. 2002). These measurements are obtained with a non-focusing rotation&nbsp; modulation collimator (RMC) imaging technique (Hurford et al. 2002). RMCs and other types&nbsp; of non-focusing imaging, however, have intrinsically limited dynamic range and sensitivity. HXR&nbsp; focusing optics can overcome both of these limitations (Section 1.2.2).&nbsp;</p> <p> The Focusing Optics X-ray Solar Imager (FOXSI) is a sounding rocket payload funded under the&nbsp; NASA Low Cost Access to Space (LCAS) program to test HXR focusing optics combined with&nbsp; silicon strip detectors for solar observations (Krucker et al. 2009). The FOXSI program is being led&nbsp; by the Space Sciences Laboratory at UC Berkeley in collaboration with the Marshall Space Flight&nbsp; Center (MSFC) and the Japan Aerospace Exploration Agency (JAXA). FOXSI is on schedule&nbsp; and on budget for a launch in October 2010. FOXSI will offer imaging spectroscopy and&nbsp; unprecedented HXR sensitivity and dynamic range. FOXSI will be !100 times more sensitive than&nbsp; RHESSI at 10 keV, and, for the first time, detect the non-thermal counterparts of quiet sun network&nbsp; flares (Section 1.2.4).&nbsp;</p> <p> Here we propose a continuation of the FOXSI program which includes data analysis&nbsp; and a second flight with an upgraded version of FOXSI. At moderate cost, we propose to&nbsp; enhance the effective area, in particular at higher energies (by a factor of !4 at 15 keV), by adding&nbsp; 3 more shells to the existing 7-shell optics (see Figure 9). Furthermore, our Japanese collaborators&nbsp; will provide, at no cost, newly available double-sided cadmium telluride (CdTe) detectors as&nbsp; a replacement for the Si detectors to allow us to take full advantage of the effective area at higher&nbsp; energies. A second flight will therefore not only allow us to continue testing HXR focusing&nbsp; optics for solar observations and also test newly developed CdTe strip detectors&nbsp; in flight but is also expected to provide a significant increase in scientific return. In&nbsp; this two year proposal, the first year (2011) will be used to upgrade the FOXSI payload and to&nbsp; analyze data from the first flight, while the second flight is planned for the midd

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Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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References

http://techport.nasa.gov/home
http://techport.nasa.gov/doc/home/TechPort_Advanced_Search.pdf
http://techport.nasa.gov/fetchFile?objectId=6561
http://techport.nasa.gov/fetchFile?objectId=3456
http://techport.nasa.gov/fetchFile?objectId=3447
http://techport.nasa.gov/fetchFile?objectId=6584
http://techport.nasa.gov/fetchFile?objectId=6560
http://techport.nasa.gov/fetchFile?objectId=3448

Dates

Metadata Created Date November 12, 2020
Metadata Updated Date December 6, 2023

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date November 12, 2020
Metadata Updated Date December 6, 2023
Publisher Science Mission Directorate
Maintainer
Identifier TECHPORT_10765
Data First Published 2010-11-01
Data Last Modified 2020-01-29
Public Access Level public
Bureau Code 026:00
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Metadata Catalog ID https://data.nasa.gov/data.json
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id cb386419-e472-46ce-add8-c0c1887b1b9d
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL http://techport.nasa.gov/view/10765
Program Code 026:000
Related Documents http://techport.nasa.gov/home, http://techport.nasa.gov/doc/home/TechPort_Advanced_Search.pdf, http://techport.nasa.gov/fetchFile?objectId=6561, http://techport.nasa.gov/fetchFile?objectId=3456, http://techport.nasa.gov/fetchFile?objectId=3447, http://techport.nasa.gov/fetchFile?objectId=6584, http://techport.nasa.gov/fetchFile?objectId=6560, http://techport.nasa.gov/fetchFile?objectId=3448
Source Datajson Identifier True
Source Hash 1976cde3cddb4e9863a86806b3bed8c2a49818e8f3924beaa1fc88f62fa9dcad
Source Schema Version 1.1
Temporal 2010-11-01T00:00:00Z/2013-10-01T00:00:00Z

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