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Message Of The Day DCS 4.2.0

SOFIA Instrument Time Estimator (SITE)

Please Check 'Notes and Known Issues' Before Proceeding

Spectroscopic Time Estimators and Tools
FIFI-LS FORCAST GRISM FLITECAM GRISM GREAT EXES ATRAN


Imaging Time Estimators
FORCAST FLITECAM FLITECAM_HIPO HAWC_Plus FPI_Plus

The following four sections of this form are for imaging configurations: select the instrument, astronomical source, telescope, observing condition constraints and calculation method. Click on the button to submit the parameters from all the sections to the server. The results are reported in a separate web page that can be resized and printed.
Instrument properties
Instrument properties:( more info)
Instrument properties:(more info, input parameter details)
Instrument properties:(more info, input parameter details)
Filter: more info Instrument Mode: Binning:

Calculation Method
Calculation method:(more info)
Select the calculation method

Astronomical Source Definition
Spatial profile and continuum brightness:(more info) Choose point or extended source.
Point source ( spatial profile):
Spatially integrated brightness for the short wavelength (SWC) filter
Emission line: ( more info) in addition to the above continuum. The output SNR or observing time will be for the sum of continuum plus line.
Single emission line at wavelength microns with line flux

Observing Condition Constraints
Note: You can read the explanatory notes for more information on the water vapor overburden.
Elevation Angle: 20o 40o 60o
Altitude in 1000's of feet: 35 36 37 38 39 40 41 42 43 44 45
Zenith Water Vapor Overburden (microns): 26.7 16.9 12.8 11.0 9.6 8.4 7.3 6.3 5.5 4.8 4.2


Notes and Known Issues
1) Windows machines should use the Firefox browser, as Microsoft Internet Explorer has known issues.
2) HAWC+ imaging and polarization sensitivity values were updated in July 2019 to reflect the in-flight (measured) instrument performance. The sensitivity values used in SITE for cycles before Cycle 6 were estimates based on the theoretical performance of the instrument. The current values are different from the July 2018 estimates by up to nearly 50%, but generally <~ 20%. Time and signal-to-noise calculations should be updated accordingly for Cycle 8 before proposal submission.
3) FORCAST sensitivity values were updated in July, 2019 to reflect the in-flight (measured) instrument performance. These sensitivity values are different from - generally better than - values previously used in SITE by <~ 30%. Time and signal-to-noise calculations should be updated accordingly for Cycle 8 before proposal submission.
4) On some platforms and browsers, such as Safari, the SITE version information may not display.
5) For HAWC+, the Cycle 7 version of SITE was incorrectly including overheads in the calculations. This was corrected as of 23 Aug 2018. Proposers are encouraged to recheck their signal-to-noise and time estimations with the revised version of SITE.
6) When the filter selections are changed, the entries in the flux boxes change to their default values (these are the fluxes for which an S/N of 4 is obtained in 900 seconds in single channel mode). The entries are set to the default values REGARDLESS of the values of time or S/N entered in the "Calculation Method" boxes. Furthermore, the entries follow the units set alongside the short wavelength box. [SPR509]
7) Note that SITE does NOT do any unit conversions for user-entered values.
8) To prevent any confusion regarding values and units, the user should perform these steps in the following order: (i) choose the desired filter or filter combination, (ii) choose the calculation method, (iii) choose the units desired, (iv) explicitly enter the fluxes (in the desired units) in both long and short wavelength boxes, and (v) click on the "Calculate" button.
9) For FORCAST, the *actual* filter configuration is determined after the TAC has awarded observing time, so that SITE may not reflect the current configuration. If filters are subsequently moved between short and long wavelength optical paths, the sensitivies will change from what is estimated here.
10) For HAWC_PLUS, in the polarization configuration, the returned/entered S/N is that for the polarized flux (p x F), not the fractional polarization ( p ) alone. If the S/N on total flux F is high, the S/N on the fractional polarization will be approximately the same as that on the polarized flux.
Version 4_2_0; October, 2019
 
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