ING Banner
Home > Astronomy > LIRIS > LIRIS Configuration


LIRIS Filters, Grisms, Prisms, Slits and Pupils

LIRIS has two filter wheels (FW1, FW2), a slit wheel (SW), a grism wheel (GW) and a pupil wheel (PW). The current configuration of each is given below. Dummies in the wheels are not explicitly listed. Filters in the filter wheels are inclined by 5 degrees in order to suppress reflections in the image. The green commands explain how to move a wheel independently of the others.

The J, H, Ks, filters mounted in LIRIS were purchased from A. Tokunaga's consortium, which is known as Mauna Kea Observatory system. The transformation between 2MASS and other photometric systems can be found here.

Note: The mr_k grism for K is less efficient than expected. It has been replaced by a different grism (test pending).

Note: Coronagraphic mode has not yet been fully characterised. It is not availble at present, since the coronagraphic mask was removed to make space for a MOS mask, but it can be included in the slit if telescope time is awarded.

Filter wheel configuration          lfwheel[1|2] <filter name>
Filter name Wheel and Pos. Cut-on [μm] Cut-off [μm] Transmission
y FW2 - 11 0.976 1.062 cold      data
j FW2 - 10 1.170 1.330 cold      data
h FW2 - 5 1.490 1.780 cold      data
ks FW2 - 2 1.990 2.310 cold      data
z FW2 - 9 0.996 1.069 cold      data
jc FW1 - 12 1.216 1.244 cold      data
pabeta FW1 - 6 1.277 1.310 cold      data
hc FW1 - 11 1.558 1.582 cold      data
ch4 FW1 - 3 1.640 1.740 cold      data
fe2 FW1 - 5 1.632 1.656 cold      data
he1 FW2 - 6 2.043 2.073 cold      data
h2v10 FW1 - 10 2.106 2.138 cold      data
brg FW2 - 7 2.150 2.182 cold      data
h2v21 FW1 - 4 2.231 2.265 cold      data
kc FW2 - 12 2.253 2.287 cold      data
All above


cold
hkspec FW2 - 3 1.4 2.5 warm    data
ucm FW1 - 9 1.177 1.186 cold
wdwspec FW1 - 1    -    - Spectropolarimetry
clear FW1 - 8    -    -    -
clear FW2 - 4    -    -    -

Slit wheel configuration          lslit <slit mask name>
Slit mask name Wheel Type Width Remarks
l0p65 SW - 1 Long slit 0.65"
l0p75 SW - 2 Long slit 0.75"
l1 SW - 3 Long slit 1.0"
lext6 SW - 4 Long slit 0.75" 6 slits with increasing offsets (maximum 450 pixel) in dispersion
direction, for much greater spectral coverage.
l2p5 SW - 5 Long slit 2.5"
l5 SW - 14 Long slit 5.0"
l10 SW - 6 Long slit 10.0"
various SW - 8,10,11,15 Multi slit masks    -
l0p75f0p25 SW - 7    -    -
clear0p25 SW - 12    -    -
clear SW - 13    -    - Clear aperture
blank SW - 9    -    - Blocked light path

Grism wheel configuration          lgrism <grism name> [<slit name>]
Grism name Wheel and Pos. Wavelength Resolution Remarks
lr_zj GW - 8 z - J R = 700
lr_hk GW - 2 H - K R = 700
mr_k GW - 6 K R = 2500 Low efficiency
hr_j GW - 3 J R = 2500
hr_h GW - 1 H R = 2500
hr_k GW - 7 K R = 2500
wdw_image GW - 9    -    - Imaging polarimetry
clear GW - 10    -    - Clear aperture

Pupil wheel configuration          lpupil <pupil name>
Pupil name Wheel and Pos. Purpose and remarks
pshortbr PW - 1 Short wavelength, broad band filters; lr_zj grism;
pcblnkxl PW - 2 Long wavelength, broad band; lr_hk grism; 10mm shield for M2
plongmd PW - 3 Long wavelength, medium band filters
pcoron PW - 4 Coronagraphic mode
phdhart PW - 6 Hartmann mask
pshortbru PW - 7 2% smaller area than pshortbr
pcblnk PW - 8 Like pcblnkxl, but with 8.83mm shield for M2
plongmidu PW - 9 2% smaller than plongmd
pcentnr PW - 11 Narrow band filters
pvdhart PW - 12 Hartmann mask
clear PW - 5 Clear aperture
blank PW - 10 Blocked light path


Top | Back

Contact:  (LIRIS Instrument Specialist)
Last modified: 27 March 2017