"SPHEREx: NASA’s Near-Infrared Spectroscopic All-Sky Survey" Brendan Crill (JPLCalTech) CFPU Seminar скачать в хорошем качестве

"SPHEREx: NASA’s Near-Infrared Spectroscopic All-Sky Survey" Brendan Crill (JPLCalTech) CFPU Seminar

Center for the Fundamental Physics of the Universe (CFPU) Seminar - Recorded August 4, 2020 http://cfpu.brown.edu Brendan Crill (Jet Propulsion Laboratory, California Institute of Technology) SPHEREx: NASA’s Near-Infrared Spectroscopic All-Sky Survey SPHEREx is a NASA Astrophysics medium Explorer mission to produce a near-infrared all-sky spectrophotometric survey. The 2-year mission will result in a spectrum for every 6-arcsecond pixel on the sky between 0.75 and 5 microns at spectral resolution varying between R=35 and 130. The mission is optimized to address three science themes: 1. inflation in the early Universe through searching for imprints of non-Gaussianity on the large scale structure in the universe, 2. the history of galaxy formation through measuring spectra of the extragalactic background fluctations, and 3. the inventory of biogenic ices in our own Galaxy by surveying ice absorption features towards stars. To achieve these goals, SPHEREx performs a unique spectroscopic survey with no moving parts in the instrument. A wide-field off-axis all-aluminum telescope feeds two 3x1 mosaics of H2RG detector arrays in the focal plane separated by a dichroic beamsplitter. Linear variable filters fixed on the focal plane assemblies allow SPHEREx to measure spectra of the entire sky in roughly 6 months through a series of exposures using a sequence of spacecraft pointings. The telescope is passively cooled to below 80K in low-Earth orbit by three V-groove radiators. An additional stage of radiative cooling is included to reduce the long wavelength focal plane temperature below 60K to reduce detector dark current. In 2019, NASA's Science Mission Directorate selected SPHEREx for implementation. In 2020, SPHEREx is in its preliminary design phase aiming for a launch in 2023.