T-ReCS Filters

T-ReCS contains up to 20 filters mounted in two wheels. This page describes the current set of filters.

Filter Name	Central lambda (µm)	lambda Range (50% trans., µm)	Trans. Curve	Trans. Data	Temp (K)	Notes
N'	11.2	10.1 - 12.5			10
N (broad 10um)	10.36	7.70 - 12.97			15
Si-1	7.73	7.39 - 8.08			77
Si-2	8.74	8.35 - 9.13			77
Si-3	9.69	9.22 - 10.15			77
Si-4	10.38	9.87 - 10.89			77
Si-5	11.66	11.09 - 12.22			77
Si-6	12.33	11.74 - 12.92			77
[Ar III]	8.99	8.93 - 9.06			10	(a)
[S IV]	10.52	10.37 - 10.54			10
[Ne II]	12.81	12.68 - 12.91			10
[Ne II] cont	13.10	12.95 - 13.17			10	(b)
PAH 8.6um	8.59	8.38 - 8.81			10	(c)
PAH 11.3um	11.30	10.98 - 11.59			10
Qa	18.30	17.57 - 19.08			25
Qb	24.56	23.62 - 25.54			25
Q (broad 20.8um)	20.68	17.41 - 25.40			25
K	2.19	1.98 - 2.39			77	(d)
L	3.85	3.56 - 4.14			77	(d)
M	4.68	4.39 - 4.96			77	(d)

The temperature is that of the filter measurement (there is only a very small change in bandpass between 77K and the operating temperature). 

Notes:

(a) Also used as continuum reference for PAH 8.6um filter.

(b) Normally used as continuum reference for [NeII] filter.

(c) Also used as continuum reference for [Ar III] filter

(d) The K, L and M filters are useful for target acquisition (of bright targets) but are not routinely available for science observations due to the low detector efficiency at short wavelengths. 

Last update 2006 December 12; Jim De Buizer