TIME millimeter wave grating spectrometer

Abstract

The Tomographic Ionized-carbon Mapping Experiment (TIME) utilizes grating spectrometers to achieve instantaneous wideband coverage with background-limited sensitivity. A unique approach is employed in which curved gratings are used in parallel plate waveguides to focus and diffract broadband light from feed horns toward detector arrays. TIME will measure singly ionized carbon fluctuations from 5 < z < 9 with an imaging spectrometer. 32 independent spectrometers are assembled into two stacks of 16, one per polarization. Each grating has 210 facets and provides a resolving power R of ~ 200 over the 186-324 GHz frequency range. The dispersed light is detected using 2-D arrays of transition edge sensor bolometers. The instrument is housed in a closed-cycle 4K-1K-300mK cryostat. The spectrometers and detectors are cooled using a dual-stage 250/300 mK refrigerator.

Detector modules and spectrometers for the TIME-Pilot [CII] intensity mapping experiment

“…al 2016. 29 A swept source was coupled to the spectrometer input, and single mode waveguide with a diode detector was placed at different fixed positions on the output arc. The resulting output profiles are shown in Fig.…”

Hafnium Films and Magnetic Shielding for TIME, A mm-Wavelength Spectrometer Array

“…1 Introduction TIME 1,2,3 is a mm-wavelength spectrometer array 4 that will map fluctuations of the 157.7 µm emission line of singly ionized carbon ([CII]) during the Epoch of Reionization (redshift z ∼ 5 to 9) 5,6 . A 14 x 0.43 arcmin instantaneous field of view corresponding to 16 x 1 spatial pixels is sampled by two banks single-polarization grating spectrometers (32 spectrometers total).…”