The University of Pennsylvania, Department of Physics and Astronomy has undertaken several successful research projects which have yielded data on the cosmic microwave background and the early Universe.

BLAST: The "Balloon-borne Large-Aperture Sub-millimeter Telescope," flies from a Long Duration Balloon (LDB) platform and incorporates a 2-meter primary mirror with large-format bolometer arrays operating at 250, 350 and 500 µm. By providing the first sensitive large-area (~0.5-40 square degrees) submillimeter surveys at these wavelengths, BLAST will address some of the most important cosmological and Galactic questions regarding the formation and evolution of stars, galaxies and clusters.

BLAST's primary goals are to:

• Measure photometric redshifts, rest-frame FIR luminosities and star formation rates of high-redshift starburst galaxies, thereby constraining the evolutionary history of those galaxies that produce the FIR/submillimeter background
• Measure cold pre-stellar sources associated with the earliest stages of star and planet formation
• Make high-resolution maps of diffuse galactic emission over a wide range of galactic latitudes
• Observe solar system objects including planets, large asteroids, and trans-Neptunian objects.

GBT:   The University of Pennsylvania, in collaboration with the National Insitute of Standards and Technology, NASA's Goddard Space Flight Center, and the National Radio Astronomy Observatory, have built 3 millimeter array of 8x8 TES detectors for the GBT. The GBT will have a better sensitivity in this range than current telescopes. The 90 GHz array will be a user instrument and is suitable for many different observations.

Some proposed uses include studying:

• star-forming regions
• the Sunyaev-Zel'dovich Effect
• high redshift galaxies
• mass loss from comets
• trans-Neptunian objects
• galactic plane studies

PAPPA: PAPPA is a balloon-borne instrument to measure the polarization of the cosmic micorwave background at millimeter wavelengths. It will search for the signature of gravity waves excited in an inflationary epoch shortly after the Big Bang. PAPPA uses a "polarimeter-on-a-chip" to instantaneously measure the Stokes I, Q, and U parameters in each pixel of the array. PAPPA is a collaboration with the University of Pennsylvania and the National Institute of Standards and Technology.
 

ACT:  The Atacama Cosmology Telescope project aims to observe the microwave sky in three frequency bands at high angular resolution and sensitivity over a substantial region of the sky.  ACT is a custom-designed 6-meter off-axis Gregorian telescope built by AMEC Dynamic Structures.  The ACT detectors are transition-edge-sensing superconducting bolometers, assembled into detector arrays and read out with SQUID multiplexers. ACT's Millimeter-Wave Bolometric Camera (MBAC) will consist of three 32x32 arrays of bolometers, with each bolometer approximately 1 square millimeter in size; each array corresponds to one of the three ACT frequency channels at 150 GHz, 220 GHz, and 270 GHz.

 
ACT's primary goals are to:

• We are working towards maps which will reveal numerous galaxy clusters through their thermal Sunyaev-Zeldovich signature.
• Measure the primordial microwave background power spectrum down to the smallest interesting angular scales of a few arcminutes.
• Detect the gravitational lensing of the microwave background by large-scale structure.
• Detect the proper motions of galaxy clusters through their kinematic Sunyaev-Zeldovich signal.
• Provide interesting information about infrared galaxies at high redshift, radio emission from distant active galaxies, and properties of dust in the Milky Way.