HARPS Exposure Time Calculator

Optical Echelle Spectroscopy Mode Version 6.2.0
The page is loading... please wait!

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 approximated by a gaussian in 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 FWHM at the airmass and wavelength of observation (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