GBT SCIENTIFIC WORKING GROUP

April 12, 1994 at 4 PM EDT


AGENDA

  1) GBT stuff on the 140 foot (Norrod)
  2) Receiver Priorities for 1995 and onward (Norrod)
  3) Update on construction  (Lockman)
  4) Spectrometer News (Escoffier)
  5) Feed Rotator etc.


 	*	*	*	*	*	*	*	*

     Status of GBT Receivers

PRIME FOCUS
     0.29-1.23 GHz  Under construction.


GREGORIAN FOCUS

     1.15-1.73    Under construction.  Single feed.
     3.95-5.85    Under construction.  Single feed.
     8.0-10.0     Done  Single feed.
     12.0-15.4    Done.  Dual feed.     
     18-22        Done.  Dual feed. 
     22-26        Done.  Dual feed.


PROPOSED RECEIVERS

TOP RANKED

     1.73-2.60  Timely experiments in 1996.  Relatively 
                inexpensive and easy to build.
     40-52      Array of 7+ elements, most single polarization,
                tertiary reflector for rapid beam switching.
                Complicated and expensive.  Personnel not yet
                available, though possible in late 1994.

LOWER RANKED
     25-75 MHz   Prime focus.  Easy and cheap to build.
     Dual S/X    For VLBI.  Optics require development.
     12-15 GHz   Array for continuum mapping.  

EXPERIMENTAL
    <10K L band  Very low Tsys for HI.  Requires substantial development.
     20K K band  Seeks very low Tsys for this popular band.  Requires 
                 a substantial development effort.
     3 mm.       To be of use it requires the telescope to exceed design
                 specs on surface accuracy and pointing.