The Gamma-Ray Imager/Polarimeter for Solar flares (GRIPS)

Albert Y. Shih; Robert P. Lin; Gordon J. Hurford; Nicole A. Duncan; Pascal Saint-Hilaire; Hazel M. Bain; Steven E. Boggs; Andreas C. Zoglauer; David M. Smith; Hiroyasu Tajima; Mark S. Amman; Tadayuki Takahashi

doi:10.1117/12.926450

17 September 2012 The Gamma-Ray Imager/Polarimeter for Solar flares (GRIPS)

Albert Y. Shih, Robert P. Lin, Gordon J. Hurford, Nicole A. Duncan, Pascal Saint-Hilaire, Hazel M. Bain, Steven E. Boggs, Andreas C. Zoglauer, David M. Smith, Hiroyasu Tajima, Mark S. Amman, Tadayuki Takahashi

Author Affiliations +

Proceedings Volume 8443, Space Telescopes and Instrumentation 2012: Ultraviolet to Gamma Ray; 84434H (2012) https://doi.org/10.1117/12.926450
Event: SPIE Astronomical Telescopes + Instrumentation, 2012, Amsterdam, Netherlands

Abstract

The balloon-borne Gamma-Ray Imager/Polarimeter for Solar flares (GRIPS) instrument will provide a near-optimal combination of high-resolution imaging, spectroscopy, and polarimetry of solar-flare gamma-ray/hard X-ray emissions from ~20 keV to >~10 MeV. GRIPS will address questions raised by recent solar flare observations regarding particle acceleration and energy release, such as: What causes the spatial separation between energetic electrons producing hard X-rays and energetic ions producing gamma-ray lines? How anisotropic are the relativistic electrons, and why can they dominate in the corona? How do the compositions of accelerated and ambient material vary with space and time, and why? The spectrometer/polarimeter consists of sixteen 3D position-sensitive germanium detectors (3D-GeDs), where each energy deposition is individually recorded with an energy resolution of a few keV FWHM and a spatial resolution of <0.1 mm3. Imaging is accomplished by a single multi-pitch rotating modulator (MPRM), a 2.5-cm thick tungstenalloy slit/slat grid with pitches that range quasi-continuously from 1 to 13 mm. The MPRM is situated 8 meters from the spectrometer to provide excellent image quality and unparalleled angular resolution at gamma-ray energies (12.5 arcsec FWHM), sufficient to separate 2.2 MeV footpoint sources for almost all flares. Polarimetry is accomplished by analyzing the anisotropy of reconstructed Compton scattering in the 3D-GeDs (i.e., as an active scatterer), with an estimated minimum detectable polarization of a few percent at 150–650 keV in an X-class flare. GRIPS is scheduled for a continental-US engineering test flight in fall 2013, followed by long or ultra-long duration balloon flights in Antarctica.

Citation Download Citation

Albert Y. Shih, Robert P. Lin, Gordon J. Hurford, Nicole A. Duncan, Pascal Saint-Hilaire, Hazel M. Bain, Steven E. Boggs, Andreas C. Zoglauer, David M. Smith, Hiroyasu Tajima, Mark S. Amman, and Tadayuki Takahashi "The Gamma-Ray Imager/Polarimeter for Solar flares (GRIPS)", Proc. SPIE 8443, Space Telescopes and Instrumentation 2012: Ultraviolet to Gamma Ray, 84434H (17 September 2012); https://doi.org/10.1117/12.926450

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available