The Cosmology Large Angular Scale Surveyor (CLASS): 40 GHz optical design
arXiv:1211.0041 · doi:10.1117/12.925464
Abstract
The Cosmology Large Angular Scale Surveyor (CLASS) instrument will measure the polarization of the cosmic microwave background at 40, 90, and 150 GHz from Cerro Toco in the Atacama desert of northern Chile. In this paper, we describe the optical design of the 40 GHz telescope system. The telescope is a diffraction limited catadioptric design consisting of a front-end Variable-delay Polarization Modulator (VPM), two ambient temperature mirrors, two cryogenic dielectric lenses, thermal blocking filters, and an array of 36 smooth-wall scalar feedhorn antennas. The feed horns guide the signal to antenna-coupled transition-edge sensor (TES) bolometers. Polarization diplexing and bandpass definition are handled on the same microchip as the TES. The feed horn beams are truncated with 10 dB edge taper by a 4 K Lyot-stop to limit detector loading from stray light and control the edge illumination of the front-end VPM. The field-of-view is 19deg x 14deg with a resolution for each beam on the sky of 1.5deg FWHM.
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Cited by in corpus (30)
- BICEP2 I: Detection Of B-mode Polarization at Degree Angular Scales
- Primordial Gravitational Waves from Axion-Gauge Fields Dynamics
- CLASS: The Cosmology Large Angular Scale Surveyor
- Second Season QUIET Observations: Measurements of the CMB Polarization Power Spectrum at 95 GHz
- The Cosmology Large Angular Scale Surveyor
- Four-year Cosmology Large Angular Scale Surveyor (CLASS) Observations: On-sky Receiver Performance at 40, 90, 150, and 220 GHz Frequency Bands
- The optical design of the six-meter CCAT-prime and Simons Observatory telescopes
- The TT, TB, EB and BB correlations in anisotropic inflation
- A Projected Estimate of the Reionization Optical Depth Using the CLASS Experiment's Sample-Variance Limited E-Mode Measurement
- The Cosmology Large Angular Scale Surveyor (CLASS): 38 GHz detector array of bolometric polarimeters
- Statistical Anisotropies in Gravitational Waves in Solid Inflation
- Two-year Cosmology Large Angular Scale Surveyor (CLASS) Observations: 40 GHz Telescope Pointing, Beam Profile, Window Function, and Polarization Performance
- Two-year Cosmology Large Angular Scale Surveyor (CLASS) Observations: A Measurement of Circular Polarization at 40 GHz
- Precision control of thermal transport in cryogenic single-crystal silicon devices
- On-sky performance of the CLASS Q-band telescope
- Transition Edge Sensors: Physics and Applications
- Gravitational wave astronomy with radio galaxy surveys
- Recovery of Large Angular Scale CMB Polarization for Instruments Employing Variable-delay Polarization Modulators
- Two Year Cosmology Large Angular Scale Surveyor (CLASS) Observations: Long Timescale Stability Achieved with a Front-End Variable-delay Polarization Modulator at 40 GHz
- Measuring the Largest Angular Scale CMB B-mode Polarization with Galactic Foregrounds on a Cut Sky
- The Cosmology Large Angular Scale Surveyor Receiver Design
- Two-year Cosmology Large Angular Scale Surveyor (CLASS) Observations: A First Detection of Atmospheric Circular Polarization at Q Band
- Calibration of Transition-edge Sensor (TES) Bolometer Arrays with Application to CLASS
- Design and characterization of the Cosmology Large Angular Scale Surveyor (CLASS) 93 GHz focal plane
- Variable-delay Polarization Modulators for Cryogenic Millimeter-wave Applications
- Cosmology Large Angular Scale Surveyor (CLASS) Focal Plane Development
- Cosmology Large Angular Scale Surveyor (CLASS): 90 GHz Telescope Pointing, Beam Profile, Window Function, and Polarization Performance
- Angular and Polarization Response of Multimode Sensors with Resistive-Grid Absorbers
- Variable-delay Polarization Modulators for the CLASS Telescopes
- High-Efficiency and Low-Noise Detectors for the Upgraded CLASS 90 GHz Focal Plane