Filters

As suggested to the STC already in 2006, NOTCam would benefit from an upgrade to the full near-IR broad-band filter set corresponding to the UKIRT photometric system ZYJHK used for instance in UKIDSS. This means purchasing the two new standard filters Z (0.84-0.93 um) and Y (0.97-1.07 um). NOTCam has an array with a particularly good response at the `blue` end, shown by comparing J-band zeropoints with INGRID, LIRIS on the WHT and NICS on the TNG. LIRIS has an untested `Y' filter, NICS has a broad `SW' filter (cut-off = 1.75mu) unsuitable for photometry, and INGRID has a so-called Z filter which is actually the same as our Yn-filter, i.e. not the new standard Z. Instruments that do or will have the new standard Z and Y filters are: WFCAM/UKIRT, UFTI/UKIRT (Y), VISTA, HAWK-I/VLT, NIRI/Gemini (Y), GMOS/Gemini, PANIC/CalarAlto, JACARA, etc.

After the STC meeting in May 2009 it was decided to upgrade NOTCam with low resolution grisms which will require custom made broad band filters. We have therefore made a joint inquiry about costs and time schedule for the following 4 new filters: the `standard' Z and Y, as well as two custom made filters for spectroscopy, here called ZY and JH.

Offers were requested from several companies (NDC Infrared Engineering Ltd., UK; Asahi Spectra Co. Ltd., Japan), and; Omega Optical Inc., US) of which the first one provided us with practically all our current NOTCam filters through the GEMINI infrared filter consortium. UKIRT got their WFCAM Y filter from NDC and their Z filter from Research Electro-Optics. More detailed information about the offer will be send directly to the STC.