Filters

 

Filters for the three channels are listed in the Table below. For an observed counts per second (CPS), the source Flux and its AB magnitude for a filter can be estimated using the following relations:
 
Ffilter = CPS x UC (ergs s-1 cm-2 A-1)
mAB = -2.5 log10 (CPS) + ZP
 
CPS : Counts per second, the source count-rate
UC : Unit Conversion for the filter (see the table below)
ZP: Zero point for the filter (see the table below)

Channel Slot Filter Name Mean λ
(A)
Δ λ
(A)
Zero Point
(ZP)
Unit Conv.
(UC)
X 10-15
FUV 0 Block Block
1 F148W CaF2-1 1481 500 18.016 ± 0.01 3.09 ± 0.029
2 F154W BaF2 1541 380 17.778 ± 0.01 3.55 ± 0.04
3 F169M Sapphire 1608 290 17.455 ± 0.01 4.392 ± 0.037
4 Grating-1
5 F172M Silica 1717 125 16.342 ± 0.02 10.74 ± 0.16
6 Grating-2
7 F148Wa CaF2-2 1485 500 17.994 ± 0.01 3.28 ± 0.025
NUV 0 Block Block
1 N242W Silica-1 2418 785 19.81 ± 0.002 0.222 ± 0.00065
2 N219M NUVB15 2196 270 16.59 ± 0.02 5.25 ± 0.082
3 N245M NUVB13 2447 280 18.50 ± 0.07 0.725 ± 0.0036
4 Grating
5 N263M NUVB4 2632 275 18.18 ± 0.01 0.844 ± 0.0096
6 N279N NUVN2 2792 90 16.50 ± 0.01 3.50 ± 0.035
7 N242Wa Silica-2
VIS 0 Block Block
1 V461W VIS3 4614 1300
2 V391M VIS2 3909 400
3 V347M VIS1 3466 400
4 V435ND ND1 4354 2200
5 V420W BK7 4200 2200
 

Filter Effective Area

Effective area of various UVIT filters are listed below. These values may be updated as and when new data is available from ground (and later in-flight) calibrations.
Effective area of UVIT FUV filters
Effective area of the FUV filters. [Download data]

Effective area of UVIT NUV filters
Effective area of the NUV filters. [Download data]

Effective area of UVIT VIS filters
Effective area of the VIS filters. [Download data]