XCELLENCE IN ASTROPHYSICS
CHIME is a novel radio telescope located in a secluded valley near Penticton, British Columbia. The telescope consists of five large, 100 x 20-meter partial-cylinder reflectors roughly the size and shape of snowboarding half-pipes packed with arrays of radio receivers located along the focus of each partial cylinder. There are no moving parts (other than the Earth). When finished, CHIME will measure more than half of the sky each day as the Earth turns. However, CHIME won’t be studying the CMB. It will be looking for evidence of dark energy by surveying 21cm (400- to 800-MHz) radio emissions in a large 3D volume of space at distances ranging from 7 billion to 11 billion lightyears. CHIME will be measuring “baryon acoustic oscillations,” or BAOs, which are periodic density fluctuations in enormous cosmic structures consisting of hydrogen gas. BAO matter clustering provides cosmologists with a “standard ruler” of approximately 490 million lightyears, used for measuring immense distances. BAO signal variations could prove to be the signs of dark energy at work. At least, that’s the hope. CHIME is essentially a phased-array radio telescope. It synthesizes an image by recording the electromagnetic signal across a stationary antenna array and then reconstructing the overhead sky from the data using 2D correlation and interferometry. CHIME will require 160 interconnected Kintex-7 FPGAs to process BAO signal data being received at several terabytes per second. FASTER THAN THE SPEED OF LIGHT The inflation theory of cosmology posits that the universe underwent a violent expansion 10 to 35 seconds after the Big Bang—a physical expansion that exceeded the speed of light. That’s pretty hard to accept if you think that the speed of light is absolute, and most of us do. Part of that Big Bang theory suggests that inflation left behind a cosmic gravitational-wave background (CGB) in addition to the CMB, and that the CGB impressed a polarization sigThird Quarter 2014
nature on the CMB. Results from the BICEP2 experiment are the first to confirm this theory. Additional results from the SPTpol camera, EBEX, POLARBEAR, the Keck Array and the BICEP3 experiment are expected to reinforce that finding. For its part, CHIME will add yet another dimension to our quest for cosmological knowledge when it starts searching for dark energy.
All Programmable FPGA and SoC modules form
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Further Reading For more technical information about the SPTpol camera, TES bolometers and the FPGA-based DFMUX readout board, check out the following references: J. E. Austermann, et al., “SPTpol: an instrument for CMB polarization measurements with the South Pole Telescope,” arXiv:1210.4970v1 [astro-ph.IM]
rugged for harsh environments extended device life cycle Available SoMs:
Ron Cowen, “Telescope captures view of gravitational waves,” Nature, March 17, 2014 Matt Dobbs, et al., “Digital Frequency Domain Multiplexer for mm-Wavelength Telescopes,” arXiv:0708.2762v1 [physics. ins-det] M.A. Dobbs, et al., “Frequency multiplexed superconducting quantum interference device readout of large bolometer arrays for cosmic microwave background measurements,” arXiv:1112.4215v2 [astro-ph.IM] J. W. Henning, et al., “Feedhorn-Coupled TES Polarimeter Camera Modules at 150 GHz for CMB Polarization Measurements with SPTpol,” arXiv:1210.4969v1 [astro-ph.IM] J. T. Sayre, et al., “Design and characterization of 90-GHz feedhorn-coupled TES polarimeter pixels in the SPTpol camera,” arXiv:1210.4968v1 [astro-ph.IM]
Platform Features • 4×5 cm compatible footprint • up to 8 Gbit DDR3 SDRAM • 256 Mbit SPI Flash • Gigabit Ethernet • USB option
Design Services • Module customization • Carrier board customization • Custom project development
Graeme Smecher, et al., “An Automatic Control Interface for Network-Accessible Embedded Instruments,” ACM SIGBED Review, Second Workshop on Embed With Linux (EWiLi 2012), Vol. 9 Issue 2, June 2012 Graeme Smecher, et al., “A Biasing and Demodulation System for Kilopixel TES Bolometer Arrays,” arXiv:1008.4587 [astro-ph.IM] K. Story, et al., “South Pole Telescope Software Systems: Control, Monitoring, and Data Acquisition,” arXiv:1210.4966v1 [astro-ph.IM]
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