Planck Surveyor
USA Participation in LFI Consortium
Planck (formerly COBRAS/SAMBA) is an
ESA (European Space Agency) mission.
The current ESA schedule has a launch date of 2004.
However there are a number of things in which US participation will add
significantly to the mission. This page addresses the LFI primarily.
Anticipated & Current USA Participation in the LFI Consortium
Both US developed bolometers and HEMTs lead the world as being the
most sensitive detectors currently available for a space mission
such as Planck.
InP HEMT amplifiers
- InP HEMTs have lowest noise and power dissipation
- InP HEMTs available only in the US
- NASA supported callaboration has significantly advanced the state of
the art in InP HEMTs
- TRW leads in the development of InP monolithic microwave integrated
circuits (MMICs)
- MMIC amplifiers are much easier to produce in large quantities
in comparison to discrete transitors and have other advantages.
- US, JPL in particular, has a great deal of cryocooler expertise
for space missions
- JPL has developed a 20 K hydrogen sorption
cooler
- JPL has pioneered the development of sorption coolers for space
- Successful shuttle demo of 10 K cooler in May 1996
- Flight qualified 20 K cooler awaiting integration with the UCSB CMB
balloon payload
- easily scalable to any cooling capacity desired, vibrationaless,
no EMI, no moving parts except for passive check valves.
- HEMT amplifier noise drops by factor greater than 2 between 70 K and
20 K.
- Simplifies thermal design
- Use of InP HEMTs cuts power dissipation by factor of 5 over GaAs HEMTs
- Possible to have passive cooling at L2 to 60 K
- Can eliminate 50 - 80 K Stirling cooler on HFI
- Mirror Temperature drops about 20 K
- prototype radiometers
- thermal design
- systematic error minimization and analysis
- procedures and planning
- industry, university, and laboratory contacts
- test procedures
- ....
Return to the Planck
page.
Return to the Smoot Group page for a complete description of Dr. Smoot's group's research activities.
Revised 21 January 1997; smoot@cosmos.lbl.gov