MAX - Technical Characteristics and Astronomical Performance

Array Type:
Rockwell 128x128 pixel high flux Si:As BIB array,

Wavelength range:
4 µm - 27 µm

Pixel pitch
75 µm

Active area fill factor
100% (focal plane architecture)

Quantum efficiency:
~ 31 %

Bad pixels:
~ 20

Dark current:
2 * 106 electrons/sec

Read noise:
1250 electrons - destructive read mode

Well capacity:
1.73 * 107 electrons

Telescopes:
The camera can be mounted on the UKIRT 3.8 m telescope.

Pixel scales:
~ 0.27"/pixel
For high accuracy work, the scale and rotation angle should be measured during your observing run.

Read out options:
dc
 No chopper
The chip will be read '#Coadds'  times,
the frames will be added and the sum will be sent to the SunSparc. 
This will be reapeated '#Repeat' times. Eventually you will get
'#Repeat' images. 
'eff.IT:' shows the effective integration time per image = FT * #Coadds 
chop
 The chopper runs: 
   ----------            ----------            object
             |          |          |
             |          |          |
              ----------            ---------- sky
             =>send      =>send
             object      sky 
             image       image
every '-' marks a read. The number of reads per chopper-plateau
is defined by '#Coadds'. The eff. integration time is 'FT' * '#Coadds'
(unit=seconds) per image.
Eventually you will have 2 * '#Repeat' images in memory.
The image-'display' and the FITS-files contain raw (integrated) data.
Note: '#Plateaus' is usually set to '1'. This parameter allows you to add 
several chopper-plateaus using the hardware coadder.
chop-d
 The chopper runs and the readout-scheme is the same as in
'chop' mode. But only the differences of consecutive images
(object-sky) are displayed and saved to disk.
(-> you will get '#Repeat' difference-images) 

Data system:
Sun SPARC-20 dedicated to camera control. All data are written to disk as FITS files, which are backed up via tar to a DAT tape.

Sensitivity:
@ 11.5 µm (filter N_11.5w2)
S/N ~ 10
source of 0.1 Jy (~ 6.2 mag)
60 sec on source
during the night of 16 Jan '96

@ Q band (filter Q)
S/N ~ 5
estimated source of 6.23 mJy
1 hour on source
extrapolated data obtained during the night of 29 Nov '96

Filter options:
all wavelength numbers are in microns @ 12 Kelvin
Name
Centre 
Wavelength
5 % cut on
5 % cut off
Width
Transmission
avg.T* /%
Status
M_4.7 
4.661 
4.257 
5.047 
0.790 
88 
in 
N_7.7 
7.694 
7.237 
8.194 
0.957 
88 
in 
N_8.7 
8.680 
8.140 
9.185 
1.045 
87 
in 
N_9.6 
9.635 
9.031 
10.262 
1.231 
84 
in 
N_10.2 
10.230 
9.606 
10.885 
1.279 
82 
in 
N_11.6 
11.582 
10.884 
12.348 
1.464 
78 
in 
N_12.4 
12.421 
11.683 
13.227 
1.544 
78 
in 
N_10.4w5 
10.160 
7.639 
12.837 
5.198 
75 
out 
N_12.5w4 
12.467 
10.357 
14.753 
4.396 
76 
out 
N_11.5w2 
11.530 
10.357 
12.825 
2.468 
57 
out 
N_PAH 
11.345 
11.167 
11.580 
0.413 
74 
in 
N_PAHcont 
11.658 
11.484 
11.903 
0.419 
68 
in 
N 
10.468 
8.291 
12.941 
4.650 
69 
in 
N_n 
11.639 
10.470 
12.947 
2.477 
66 
in 
Q 
20.287 
18.163 
22.397 
4.234 
40 
in 
Q_16.4 
16.428 
16.047 
16.833 
0.786 
47 
out 
Q_16.7 
16.966 
16.603 
17.342 
0.739 
40 
out 
Q_17.7 
17.688 
17.327 
18.083 
0.756 
48 
out 
Q_19.9 
19.913 
18.966 
20.844 
1.878 
60 
in 
Q_21.4 
21.436 
20.647 
22.197 
1.550 
47 
out 
Q_22.7 
22.722 
22.007 
23.408 
1.401 
35 
out 

* avg. Transmission: The avg. Transmission represents the average level of the plateau in the filter trace. There are usually regions of higher and lower transmission than the average.

Peter Bizenberger
biz@mpia-hd.mpg.de
Tel. (+49) 6221 528 311