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October 30, 1997

3

2.2

Dewar Temperature

The dewar now has a temperature sensor and heater. For normal operation, the temperature controller
should be used to set the detector temperature to 80.0K. If the controller is not used, drifts can occur
as the telescope is moved, resulting in dark current instabilities in the array. The new array is not
thought to be more sensitive to these effects than the previous detector, but some of the anomalies
previously seen by observers with the original QUIRC detector may have been due to this effect.

2.3

Camera Sensitivity

The following sensitivity estimates are based on observations of 2 standard stars at the UH 2.2m
telescope on 2/6/96. The Point SRC (source) and Mag/arcsec

2

values are for 1 minute of on-source

integration time, 5

. The point source detection values below assume a PSF of 0.5 arcsec FWHM.

Table 2. QUIRC Sensitivity

UH 2.2m Telescope

Filter

Point SRC(Mag)

Mag/arcsec

2

Jy/ADU (1 sec)

J

18.6

17.9

1.052e-6

H

17.8

17.1

8.295e-7

K

16.2

15.5

9.622e-7

H+K

18.6

17.9

2.3.1

QUIST sensitivity

The following numbers are based on observations of standard stars using QUIST at the UH 0.6m
telescope on 2/9/97. The Point SRC (source) and Mag/asec

2

are for 1 minute of integration time, 5

sigma. The point source detection values below assume a PSF of 2.5 pixels FWHM.

Table 2. QUIRC Sensitivity on QUIST

Filter

Point SRC(Mag)

Mag/arcsec

2

Jy/ADU (1 sec)

K’

14.5

16.4

7.644e-5

Hs

14.7

16.6

2.291e-4

Hl

14.3

16.2

2.391e-4

2.12

12.0

15.0

4.563e-6

2.26

12.7

15.5

1.412e-5

3

Setup and Observing with QUIRC

The nominal orientation for QUIRC at the 88-inch telescope is for the black electronics box on the
dewar (the utility box) to point North (toward the control room). Then the resulting FITS data files
written by the program have N up and E to the left (i.e. the (0,0) pixel is in the SE corner).

Summary of Contents for QUick Infrared Camera

Page 1: ...Observer s Guide for QUIRC K W Hodapp J L Hora M R Metzger University of Hawaii October 30 1997...

Page 2: ......

Page 3: ...ith QUIRC The qcdcom program controls taking exposures and writing data in FITS format to disk operates the moving parts of the instrument such as the shutter filter wheel and pupil mask communicates...

Page 4: ...ation differences for integration times less than 1 second Therefore short exposures should be avoided particularly when exposing dome flats it is far better to dim the lights with the domelight dimme...

Page 5: ...elow assume a PSF of 0 5 arcsec FWHM Table 2 QUIRC Sensitivity UH 2 2m Telescope Filter Point SRC Mag Mag arcsec2 Jy ADU 1 sec J 18 6 17 9 1 052e 6 H 17 8 17 1 8 295e 7 K 16 2 15 5 9 622e 7 H K 18 6 1...

Page 6: ...ted image display capability A separate program should be used to display the data One option is to use the viewfits program vf This is a display program developed by Tony Denault at the IRTF that dis...

Page 7: ...ode is running The command to download the current standard DSP code is the following df quirc Occasionally the download will fail if the camera is in some undetermined state and a reset will need to...

Page 8: ...rash for any reason the parameters it reads in may be old and you may need to set them again Typically only resetting the file number is necessary 3 3 Taking exposures For each object you are observin...

Page 9: ...telescope and guide probe and turns the guider back on On the 88 this communicates with Atlas and MiniOtto over the ethernet to perform the guider movements and on CFHT commands are sent over a seria...

Page 10: ...6 H K dual 1 8 m 2 794 20 6 6 1 7 H2BP23 2 12 m 0 914 2 1 7 1 8 2260BP60 2 260 m 2 794 20 6 8 2 1 1560BP120 1 56 m 9 2 2 1710BP120 1 71 m 10 2 3 1 989BP50 1 989 m 11 2 4 1 506 60 1 506 m 12 2 6 1 107...

Page 11: ...th auto or the shutter will not open Also note that you should always do only one filter DARK followed by exactly one filter BACK always in pairs otherwise the filter wheel will get lost and require a...

Page 12: ...chop image and displayed in vf Therefore the observer can take focus frames acquire and center the object etc without saving all the images as separate data files This avoids filling the disk with use...

Page 13: ...P initialization commands In general you will need to initialize the DSP processor in the Leach electronics after power up or after a DSP reset because its cold reset state is not appropriate for runn...

Page 14: ...rform first data read of double correlation pair store image in memory 4 Turn off output amplifiers 5 Open the shutter and wait for a predetermined exposure time 6 Close the shutter 7 Turn on output a...

Page 15: ...e double correlated read on off Controls whether the device is read out before and after the shutter opening or only after If reading before and after the difference between the two are taken and this...

Page 16: ...o stay open slightly longer The exposure time recorded in the header however will reflect the true amount of time the shutter was open filter hnum commandi Set filter This command selects the filter s...

Page 17: ...fp q940811 go h num i Start exposure Go is the command to take an exposure As described above according to the param eters which are set go may reset the chip open the shutter and close it a predeterm...

Page 18: ...resulting image to a disk file set hparami n Set parameter Certain program parameters can be set or unset with this command To set a param eter for example save one issues the command set save To uns...

Page 19: ...direct access to the DSP computer hall hnloopi Read Hall sensors read the Hall effect sensors nloop times The filter wheel 1 sensor is displayed and depending on the position of the switch either the...

Page 20: ...en data is used as a seed for a random number generator and 65536 words of random data are sent per loop diag l3 hcnt fr cg data i Timing board loopback test Loopback test with timing board in place M...

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