HARPS Exposure Time Calculator

Optical Echelle Spectroscopy Mode Version 6.0.1
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Target Input Flux Distribution

Template Spectrum Redshift
z =
Target Magnitude and Mag.System:   
= Vega
Magnitudes are given per arcsec2 for extended sources
MARCS Stellar Model
Upload Spectrum
Blackbody Temperature: K
Power Law Index:           F(λ) ∝ λindex
Emission Line
Lambda: nm
Flux: 10-16 ergs/s/cm2 (per arcsec2 for extended sources)
FWHM: nm

Spatial Distribution: Point Source

Sky Conditions

Moon phase: days from new Moon
Seeing/Image Quality:
For point sources, the resulting Image Quality FWHM is modeled by the ETC considering the transfer functions of the atmosphere and telescope. See the helpfile for details.
Seeing: arcsec FWHM in V-band at zenith (use this value in the proposal)
              Probability ---% of realising the seeing ≤ 0.80 arcsec
IQ: arcsec (to be used for the OB constraint set)
              The corresponding seeing and probability will be indicated in the ETC output page
Image Quality is not a parameter in AO modes

Instrument Setup

The S/N and flux estimates in polarimetric mode are computed for fiber A only taking into account the transmission of the polarimetric optics. Fiber B suffers an efficiency loss of ~30% with respect to fiber A solely due to the fiber transmission.
CCD mode:

Exposure Time:


Include exposure times for S/N:
Tables:  Toggle All / No Tables
Spectral Format
Expected Counts
Graphs:  Toggle All / No Graphs
Input Spectrum
Maximum Intensity