Atacama Pathfinder EXperiment APEX
OLD pages, check new site
Observing time calculator
MPIfR Bonn   ESO   Onsala Space Observatory
  APEX TWIKI CONTACT SEARCH HELP NEWS DISCLAIMER

Home > Instrumentation > Heterodyne Instruments > Observing time calculator > Calculator ON/OFF Integration Time Estimator

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]

Recent changes:


DateVersionInformation
2020-03-136.1.2NFLASH230/345 Trec file modified added a point in the limit of the band. Overhead NFLASH230 changed, use the same values than FLASH
6.1.2shows RMS value in mK unit too
2020-02-256.1.1NFLASH460 modified to 2 polarization, change in number of channels availables in NFLASH460, SEPIA180, SEPIA345
2020-02-136.1No changes in computation. Added FE names NFLASH230, NFLASH460
2018-09-106.0.5No changes in computation. Updated FE names (SEPIA180, SEPIA660. Added table with tuning ranges per FE. Added warning messages when user inputs incorrect setups
2018-08-316.0.4Includes updates for 2SB SEPIA-B9 after installation and commissioning: Trx curves, sideband rejection and extended tuning range [583-724 GHz]
2018-07-026.0.3Updates with new SEPIA-B9 setup, new tunning range and change from DSB to 2SB
2018-03-216.0.2LASMA receiver added
2017-09-066.0.1New version 6.0.1, Fix a bug in off time estimation for integration time calculator V6.0
2017-08-306.0New 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













Instrument Frequency Range:


Instrument Frequency Range [GHz]
NFLASH230
200.0 - 270.0
NFLASH460
385.0 - 500.0
SEPIA180
159.0 - 211.0
SEPIA345
272.0 - 376.0
SEPIA660
578.0 - 738.0
LASMA345
262.0 - 374.0
CHAMP690
620.0 - 720.0
CHAMP810
780.0 - 950.0
FLASH345
262.0 - 374.0
FLASH460
374.0 - 516.0
PI230
200.0 - 270.0
Het230
214.0 - 275.0
Het345
267.0 - 378.0
Het460
385.0 - 500.0
SEPIA660-4
578.0 - 738.0