Instrument's Characteristics

In this page are listed the main characteristics of the imaging mode and the filters of the instrument.
This is intended as a quick reference. A detailed description of HAWK-I can be found in the user's manual

Imaging mode: characteristics and sensitivity

The detectors

HAWK-I detectorsHAWK-I Detectors definition
Characteristics of the four detectors
Detector Parameter Q1 Q2 Q3 Q4
Detector numbering #66 #78 #79 #88
Gain [e-/ADU] 1.705 1.870 1.735 2.110
Operating temperature 75K, controlled to 1mK
Dark current [e-/s] (at 75K) between 0.10 & 0.15
Read noise* (DCR) ~ 12 e-
Read noise* (NDR) ~ 5 e-
Linear range (1%) 60.000e- (~30.000 ADUs)
Saturation level between 40.000 & 50.000 ADUs


*: The RON depends on the number of non-destructive samples during the integration.
DCR (Double-Correlated Read) refers to two samples, i.e. minimum DIT ~ 1.25s.
NDR (Non-Destructive Read) refers to > 10 samples, i.e. DIT > 10s

The gap

There is a small mis-alignment between the detectors. Quadrants 2,3 & 4 are tilted with respect to quadrant 1 by 0.13, 0.04 & 0.03degrees respectively.

Details of the gap between detectors

List of filters offered for HAWK-I

Click on the filter name to retrieve the transmission curve
Filter Name Central Wavelength (μm) Width (μm) Transmission (%)
Y 1.021 0.101 92
J 1.258 0.154 88
H 1.620 0.289 95
Ks (1) 2.146 0.324 82
Ks (2) 2.146 0.324 82
CH4 1.575 0.112 90
H2 2.124 0.030 90
Brγ 2.165 0.030 77
NB1060 1.061 0.009 70
NB1190(3) 1.186 0.012 75
NB0984(4) 0.984 0.005 60
NB2090 2.095 0.020 81
(1) Filter used from Aug 2007 until Dec 3, 2007. Showed some structure for the Nov 2007 Science Verification run.(2) New Ks filter, used starting Jan 2008. (3) Not offered from P90, to be inserted during P93. (4) Visitor filter, please consult for usage. To be removed during P93. 
Plot of filters efficiency