학술논문

Current Status of the Ali CMB Polarization Telescope Focal Plane Camera
Document Type
Periodical
Source
IEEE Transactions on Applied Superconductivity IEEE Trans. Appl. Supercond. Applied Superconductivity, IEEE Transactions on. 31(5):1-5 Aug, 2021
Subject
Fields, Waves and Electromagnetics
Engineered Materials, Dielectrics and Plasmas
Detectors
Bolometers
Resonators
Prototypes
Optical device fabrication
Optical resonators
Optical polarization
B-modes
Cosmic Microwave Background
cryogenics
kilopixel focal planes
low noise amplifier
microwave multiplexing readout
radio frequency system-on-chip
Tibet
transition-edge sensor
Language
ISSN
1051-8223
1558-2515
2378-7074
Abstract
Ali CMB Polarization Telescope (AliCPT) is the first Cosmic Microwave Background (CMB) polarimeter with a large focal plane camera to be deployed in the Northern Hemisphere, in the Tibetan Plateau. Here we present the design of a dichroic (90/150 GHz) focal plane camera capable of hosting up to 32,376 Transition-Edge Sensor (TES) bolometers operating from a base temperature of 280 mK. Detectors are fabricated as monolithic arrays of 1,704 feedhorn-coupled and polarization-sensitive TES bolometers that are packaged in independent modules and read out with a microwave multiplexing architecture. A custom RFSoC-based system manages the multiplexing readout. Prototype AliCPT pixels have been fabricated and characterized, demonstrating passband performance within 2.5% of design and cross-polarization systematic sensitivity $\leq$2%.