Executive summary
Clusters survey
Infrared background
Gravity waves
Spectral distortions
Legacy archive
Mission description
Documents Supporters

Executive Summary

PRISM is a large-class mission that will carry out the ultimate survey of the microwave to far-infrared sky in both intensity and polarization, as well as measure its absolute spectrum. PRISM will consist of two instruments:

  1. a high angular resolution polarimetric imager with a 3.5 m telescope cooled to around 4K to reduce thermal noise, particularly in the far-infrared bands; and
  2. a low angular resolution spectrometer to compare the sky frequency spectrum to a near perfect reference blackbody.
The joint exploitation of the data from these co-observing high-performance instruments will enable PRISM to make breakthrough contributions by answering key questions in many diverse areas of astrophysics and fundamental science. In particular:
  1. Using the Sunyaev-Zeldovich effect, PRISM will detect all clusters in the observable universe of mass larger than 1014 solar masses, and a large fraction of those with mass above 5×1013 solar masses. (see Clusters survey)
  2. Owing to its high sensitivity and angular resolution in the far infrared, PRISM is uniquely situated to investigate the cosmic infrared background (CIB) produced by dusty galaxies undergoing star formation in the early universe (see Infrared Background)
  3. Because of its broad frequency coverage and extreme stability, PRISM will be able to detect the rotational modes of CMB polarization. These are produced by gravitational waves emitted during the inflation process in the very early universe, so PRISM provides unique tests of ultra-high-energy physical phenomena (see Gravity Waves)
  4. The PRISM absolute spectrometer will measure the spectrum of the CMB more than three orders of magnitude better than FIRAS. This will probe new physics through the measurement of CMB spectral distortions (see Spectral Distortions)
  5. The hundreds of intensity and polarization maps of PRISM will constitute a legacy archive useful for almost all branches of astronomy (see Legacy Archive)