# Sensitivities

All sensitivities on this page are 5-sigma in 1 hour of on-source integration. Point source sensitivities assume 0.5'' seeing, while surface brightness sensitivities are per pixel.

 Filter Sensitivity mag for 1 e-/s Name L_cen(A) Width(A) (mag) (mag/pixel) U 3600 560 25.8 28.7 25.7 B 4400 1080 27.4 30.3 28.4 V 5500 1000 27.0 29.9 28.3 Rc 6600 1170 26.6 29.5 28.2 Ic 8050 1460 26.0 28.9 27.9

## Narrow-band filters

 Filter Sensitivity uJy for 1e/s Name L_cen(A) Width(A) (uJy) (erg/s/cm^2) (uJy/pixel (erg/s/cm^2/pix) N373 3737 58 0.32 4.0E-17 0.024 3.0E-18 0.92 N386 3865 110 0.22 4.9E-17 0.017 3.8E-18 0.41 N487 4882 53 0.23 1.5E-17 0.018 1.2E-18 0.43 N502 5025 60 0.22 1.6E-17 0.017 1.2E-18 0.36 N512 5121 60 0.26 1.8E-17 0.020 1.4E-18 0.36 N642 6428 127 0.22 2.0E-17 0.017 1.6E-18 0.16 N658 6588 73 0.31 1.6E-17 0.024 1.2E-18 0.30 N670 6709 85 0.27 1.5E-17 0.021 1.2E-18 0.24

Conversion from Jy to flux System
To convert from uJy to an emission line flux, use the following formula: For example, the point source emission line sensitivity of the N487filter is (3e-14 x 0.23 x 53)/48822 =1.53e-20 W/m2

`1 Jy = 10^-23 erg sec^-1 cm^-2 Hz^-1`
AB magnitude System
This magnitude system is defined such that, when monochromatic flux f is measured in erg sec^-1 cm^-2 Hz^-1,
`m(AB) = -2.5 log(f) - 48.60`
where the value of the constant is selected to define m(AB)=V for a flat-spectrum source. In this system, an object with constant flux per unit frequency interval has zero color.

References:

• Oke, J.B. 1974, ApJS, 27, 21
Conversion from AB magnitudes to Johnson+ magnitudes:
The following formulae convert between the AB magnitude systems and those based on Alpha Lyra:
`     B	=  B(AB) + 0.163	(+/- 0.004)     V	=  V(AB) + 0.044	(+/- 0.004)    Rc	= Rc(AB) +-0.117	(+/- 0.006)    Ic	= Ic(AB) +-0.342	(+/- 0.008)`
Source: Frei & Gunn 1995
The number of photons incident through Standard Johnson-Cousine system at the top of the atmosphere
Band lambda_c dlambda/lambda Flux at m=0 Flux at m=0

um
Jy erg-1 s-1 cm-2 A-1
U 0.36 0.15 1810 4.19e-9
B 0.44 0.22 4260 6.60e-9
V 0.55 0.16 3640 3.61e-9
Rc 0.64 0.23 3080 2.26e-9
Ic 0.79 0.19 2550 1.23e-9

Reference: Bessel  (1979)
`1 Jy = 1.51e7 photons sec^-1 m^-2 (dlambda/lambda)^-1`