Data Reduction Frequently Asked Questions

Are there any colour transformations available for the HAWK-I filters and another filter system?

 

The UK in-kind HAWK-I archive reprocessing and new ESO HAWK-I imaging pipeline use the 2MASS catalogue to astrometrically and photometrically calibrate the science fields.
The colour transformations used for the conversion between the HAWK-I photometric system and the system used for photometric calibration (e.g. 2MASS) can be found in the fits tables included in the data distribution (HIERARCH ESO PRO CATG = PHOTCAL_TAB).

For the current HAWK-I detectors and filters, the transformations to the 2MASS filters are:

 

Y = 1.52 * Jmag - 0.52 * Hmag

 

J = 0.85 * Jmag + 0.15 * Hmag

 

H = 0.06 * Jmag + 0.94 * Hmag

 

Ks = 0.03 * Jmag + 0.97 * Kmag

 

CH4 = 0.06 * Jmag + 0.94 * Hmag

 

H2 = 0.03 * Jmag + 0.97 * Kmag

 

BrG = 0.03 * Jmag + 0.97 * Kmag

 

NB0984 = 1.62 * Jmag - 0.62 * Hmag

 

NB1060 = 1.50 * Jmag - 0.50 * Hmag

 

NB1190 = 0.85 * Jmag + 0.15 * Hmag

 

NB2090 = 0.03 * Jmag + 0.97 * Kmag