Inputs to the Calculation

The tables below show the user input parameters, telescope and environment parameters, and derived parameters used by the Calculator to calculate the integration time or sensitivity.

Units in the tables are string representations of astropy units:

User input parameters

Parameter	Label	Default value	Default unit	Permitted range or values	Permitted units
Integration time	t_int	100	s	> 0	s, min, h
Sensitivity	sensitivity	3.0	mJy	> 0	uJy, mJy, Jy
Bandwidth	bandwidth	100	MHz	> 0	Hz, kHz, MHz, GHz
Observing frequency	obs_freq	406	GHz	35 - 950	GHz
Number of polarizations	n_pol	2	N/A	1, 2	N/A
Percentile water profile	weather	25	N/A	5 - 95	N/A
Elevation	elevation	45	deg	25 - 85	deg

Telescope and Environment parameters

Parameter	Label	Value	Unit	Notes
Surface RMS	surface_rms	25	micron
Dish radius	dish_radius	25	m	This parameter may be edited for performing comparisons. Permitted values are in the range 1-50 m.
Ambient temperature	T_amb	270	K
Temperature of CMB	T_cmb	2.726	K
Forward efficiency	eta_eff	0.95
Illumination efficiency	eta_ill	0.8
Spillover efficiency	eta_spill	0.95
Lowered efficiency due to blocking	eta_block	0.94
Polarisation efficiency	eta_pol	0.995

Derived parameters

Parameter	Label	Unit
Atmospheric transmittance	transmittance
Atmospheric temperature	T_atm	K
Dish efficiency	eta_a
System efficiency	eta_s
System temperature	T_sys	K
Sky temperature	T_sky	K
System equivalent flux density	sefd	J / m2