APEX - Calculator

ON/OFF Integration time estimator V 6.1.2
Use this calculator for on-off observations. If you are planning on-the-fly mapping, you should instead use the dedicated OTF Calculator The (average) elevation of the source, the receiver temperature, required σ (in K), and the spectral resolution, the on-source integration time can be estimated. System overheads include telescope movements, software overheads, observing mode efficiency, etc. Setup + calibration overheads include source acquisition, pointing, focus, receiver tuning and calibration scans. Note about overheads. For an overview of the atmospheric transmission and the possible backend configurations for each receiver, check our atmospheric transmission tool.
	Heterodyne receiver:
	Tuning Freq:	[GHz]
	Line Freq [+6 & -2 GHz from tuning]:	[GHz]
	Side Band:
	Full resolution Δv [ channels] :	[km/s]
	Manual resolution Δv:	[km/s]
	pwv :	[mm H₂O]
	Source elevation:	[deg]
	rms (0 [mK]):	[K]

	Results
	Tau (source elev deg)	80818.013
	Trec [K]	78.3
	Tsys [K] (source elev deg)	INF
	TsysImage [K] (source elev deg)	78.3
	Beam [arcsec]	27
	Position Switching On time	0.000 [s]
	Total Position Switching time	0.000 [s]
	Beam Switching On time	0.000 [s]
	Total Beam Switching time	0.000 [s]

Date	Version	Information
2020-03-13	6.1.2	NFLASH230/345 Trec file modified added a point in the limit of the band. Overhead NFLASH230 changed, use the same values than FLASH
	6.1.2	shows RMS value in mK unit too
2020-02-25	6.1.1	NFLASH460 modified to 2 polarization, change in number of channels availables in NFLASH460, SEPIA180, SEPIA345
2020-02-13	6.1	No changes in computation. Added FE names NFLASH230, NFLASH460
2018-09-10	6.0.5	No changes in computation. Updated FE names (SEPIA180, SEPIA660. Added table with tuning ranges per FE. Added warning messages when user inputs incorrect setups
2018-08-31	6.0.4	Includes updates for 2SB SEPIA-B9 after installation and commissioning: Trx curves, sideband rejection and extended tuning range [583-724 GHz]
2018-07-02	6.0.3	Updates with new SEPIA-B9 setup, new tunning range and change from DSB to 2SB
2018-03-21	6.0.2	LASMA receiver added
2017-09-06	6.0.1	New version 6.0.1, Fix a bug in off time estimation for integration time calculator V6.0
2017-08-30	6.0	New version 6.0 available. New set of overhead parameters per instrument, measured from data obtained in 2016. SEPIA-B7 added, The specification values for SEPIA-B7 are estimates and will need to be updated after successful installation and commissioning

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