Newsletter - 10 August 1992

This is another update concerning the current status of instruments
at CFHT.  Comments and suggestions about the newsletter may be
emailed to newsletter@cfht.hawaii.edu or newsletter@uhcfht.bitnet
************************************************************************


                     Service Observing Trial
 
CFHT is accepting proposals for "small" observational programs for
the 93I semester using either FOCAM (with CCDs) or with the Redeye
1-2.5 microns infrared cameras that can be carried out in a service
observing mode.  Proposals should be limited to standard instrument
setups involving very specific observations easily carried out by
a CFHT Resident Astronomer, and should not require any special
equipment or complicated instructions.  Total time required for
taking data (including any calibration frames) should be no more
than one night.  The characteristics of FOCAM (and CCDs) are given
in the current FOCAM Users Manual available from CFHT Headquarters. 
The performance of the Redeye cameras is described in the
accompanying newsletter item.  
 
The CFHT TAC has agreed to set aside a small block of contiguous
nights during the 93I semester for a trial of service observing
using one instrument, the choice of which will depend on the number
and quality of proposals submitted.  These proposals should use the
same Observing Time Request form as normal proposals, but should be
sent to:
 
     Service Observing Requests
     c/o Dr. Guy Monnet, Executive Director
     Canada-France-Hawaii Telescope Corp.
     P.O. Box 1597
     Kamuela, HI 96743
     U.S.A.
 
The deadline for reception is October 1, 1992.

Any inquiries regarding this matter should be directed to John
Glaspey, Associate Executive Director, at the same address or via
email to glaspey@cfht.hawaii.edu (Internet) or glaspey@uhcfht
(Bitnet).


********************** ANNOUNCEMENT ***********************

The new CFHT "Redeye" infrared cameras will be available to users starting 
January, 1993. Interested observers are encouraged to apply to use these 
instruments during the upcoming round of proposals. Both the narrow field and 
wide field modes will be available, at either the f/8 or the f/35
focus. Preliminary tests of the system in the lab and on the sky with
the telescope indicate good overall performance. We will characterize 
the cameras in depth during the upcoming August 16-17 engineering 
run and interested parties can contact Doug Simons at CFHT for up-to-date 
performance values. Until then, the projected performance levels listed
below should be accurate enough to allow you to design observing proposals.


			REDEYE SPECIFICATIONS

We currently have in Waimea two complete cameras. The cameras are essentially 
identical except one houses 1.7:1.0 reimaging optics, while the other houses 
0.7:1.0 optics. To date, we have received from Rockwell only one of our 
two science grade NICMOS3 detectors. If the second science grade array
does not arrive before the beginning of Semester I, 1993, we will block 
schedule runs and swap reimaging optics in the cryostat containing the science 
grade array - a procedure that takes about ~1 day due to the thermal cycle
time of the cryostats. Tests of our engineering grade array show that it is 
not suitable for scientific use due to poor cosmetics and a non-linear 
photometric response.


The basic performance characteristics expected include:

Detector:	Rockwell NICMOS3 Hg:Cd:Te array with 256x256 pixels
		& 40 micron pitch

Wavelength
Range:		1 - 2.5 microns


Plate Scales:	Focus	    Narrow Field Camera	    Wide Field Camera
		-----	    -------------------	    -----------------
		f/8		0.2"/pixel		0.5"/pixel

		f/35		0.04"/pixel		0.1"/pixel


Stock
Filters:	Central Wavelength	Feature 	Bandpass
		------------------	-------		--------

		  1.25 um		J-band
		  1.65			H-band
		  2.20			K-band
		  2.18 			K'-band*
		  2.122			H2 (S1)		   1%
		  1.644			[FeII]		   1%
		  1.282			Pa-beta		   1%
		  2.295			CO (2-0) 	   1%
		  2.165			Br-gamma	   1%
		  2.26			Continuum K**	   3%

		* The K' filter is very similar to a K filter except the 
		bandpass has been shifted slightly to the blue to cut 
		the thermal background. You are encouraged to read 
		Wainscoat and Cowie (A.J., vol. 103, pg. 332) for further 
		information about this filter.

		**intended to complement other narrow band ~2 um filters to 
		sample continuum flux

		Please note that each camera can house visitor 1" round
                (1.05 inches MAX OD), coolable filters as well. The maximum 
                thickness for all filters is 6 mm. If you would like to use 
		your own filters please send them to CFHT at least 2 weeks 
		before your scheduled run so we have adequate time to mount 
		them in one of the cameras. Cold filter transmission curves 
		can be sent to interested users upon request. We have no 
		accommodation for CVFs.


Read Noise:	Expecting ~50 e-/read. In most cases observers will be
		background limited.


Dark Current:	Expecting ~1 e-/sec.


Linear Dynamic
Range:		~450,000 e- or ~90% of full well.


Total
Throughput:	J ~ 10%
		H ~ 18%
		K ~ 20%

		-> these include the camera optics, telescope optics, etc.


Sky
Background:	J ~ 16 mag/arcsec^2
		H ~ 14.5 mag/arcsec^2
		K ~ 13.0 mag/arcsec^2
		K' ~ 13.5 mag/arcsec^2


Data 
Acquisition:	The Pegasus data acquisition environment will be used
		to control the cameras, hence most experienced CFHT observers 
		should be able to run the system with little training. In most
		respects operating the cameras will be similar to running
		one of the facility CCD cameras. 


Calibration:	Flat fields can generally be derived either from sky flats
		or dome flats using incandescent lights. Observers are reminded
		that the sky can change significantly on time scales of only
		~30 minutes and frequent sky sampling may be needed to 
		complete some projects.


			FUTURE DETAILS
 
An assortment of tests and refinements to the Redeye system will occur 
throughout the next ~6 months, in preparation for the January '93 
commissioning date. Prospective users are encouraged to call Doug Simons 
at the CFHT Waimea Headquarters or e-mail to "redeye-dev@cfht.hawaii.edu" for 
further information about developments in the Redeye program.