FORS Exposure Time Calculator
Optical Spectroscopy Mode
Version 6.1.1
Description
FAQ
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Target Input Flux Distribution
Template Spectrum
O5V (Pickles)
O9V (Pickles)
B1V (Kurucz)
B2IV (Pickles)
B3V (Kurucz)
B8V (Kurucz)
B9III (Pickles)
B9V (Pickles)
A0III (Pickles)
A0V (Pickles)
A1V (Kurucz)
F0V (Kurucz)
G0 (Pickles)
G2V (Kurucz)
K2V (Pickles)
K7V (Pickles)
M2V (Pickles)
Planetary Nebula
HII Region (ORION)
Elliptical Galaxy
S0 Galaxy
Sa Galaxy
Sb Galaxy
Starburst Galaxy 1
Starburst Galaxy 2
Starburst Galaxy 3
Starburst Galaxy 4
Starburst Galaxy 5
Starburst Galaxy 6
E Galaxy (GALEV)
QSO
Redshift
z =
Target Magnitude and Mag.System:
U
B
V
R
I
=
Vega
AB
Magnitudes are given per arcsec
^{2}
for extended sources
MARCS Stellar Model
==============================
Spherical Geometry (87 models)
==============================
Teff=4000 log(g)=-0.5 [Fe/H]= 0 M= 1
Teff=4000 log(g)= 0.0 [Fe/H]=-1 M= 1
Teff=4000 log(g)= 0.0 [Fe/H]=-1 M= 5
Teff=4000 log(g)= 0.0 [Fe/H]= 0 M= 1
Teff=4000 log(g)= 1.0 [Fe/H]=-4 M= 5
Teff=4000 log(g)= 1.0 [Fe/H]=-2 M= 1
Teff=4000 log(g)= 1.0 [Fe/H]=-2 M= 5
Teff=4000 log(g)= 1.0 [Fe/H]=-1 M= 1
Teff=4000 log(g)= 1.0 [Fe/H]=-1 M= 5
Teff=4000 log(g)= 1.0 [Fe/H]= 0 M= 1
Teff=4000 log(g)= 1.0 [Fe/H]= 0 M= 5
Teff=4000 log(g)= 2.0 [Fe/H]=-4 M= 1
Teff=4000 log(g)= 2.0 [Fe/H]=-4 M= 5
Teff=4000 log(g)= 2.0 [Fe/H]=-2 M= 1
Teff=4000 log(g)= 2.0 [Fe/H]=-1 M= 1
Teff=4000 log(g)= 2.0 [Fe/H]=-1 M= 5
Teff=4000 log(g)= 2.0 [Fe/H]= 0 M= 1
Teff=4000 log(g)= 2.0 [Fe/H]= 0 M= 5
Teff=4000 log(g)= 3.5 [Fe/H]=-4 M= 1
Teff=4000 log(g)= 3.5 [Fe/H]=-2 M= 1
Teff=4000 log(g)= 3.5 [Fe/H]=-1 M= 1
Teff=4000 log(g)= 3.5 [Fe/H]= 0 M= 1
Teff=4500 log(g)= 0.0 [Fe/H]=-1 M= 1
Teff=4500 log(g)= 0.0 [Fe/H]= 0 M= 1
Teff=4500 log(g)= 1.0 [Fe/H]=-2 M= 1
Teff=4500 log(g)= 1.0 [Fe/H]=-2 M= 5
Teff=4500 log(g)= 1.0 [Fe/H]=-1 M= 1
Teff=4500 log(g)= 1.0 [Fe/H]= 0 M= 1
Teff=4500 log(g)= 2.0 [Fe/H]=-2 M= 1
Teff=4500 log(g)= 2.0 [Fe/H]=-2 M= 5
Teff=4500 log(g)= 2.0 [Fe/H]=-1 M= 1
Teff=4500 log(g)= 2.0 [Fe/H]= 0 M= 1
Teff=4500 log(g)= 3.5 [Fe/H]= 0 M= 1
Teff=5000 log(g)= 0.0 [Fe/H]=-1 M= 1
Teff=5000 log(g)= 0.0 [Fe/H]=-1 M= 5
Teff=5000 log(g)= 0.0 [Fe/H]= 0 M= 1
Teff=5000 log(g)= 0.0 [Fe/H]= 0 M= 5
Teff=5000 log(g)= 1.0 [Fe/H]=-2 M= 1
Teff=5000 log(g)= 1.0 [Fe/H]=-2 M= 5
Teff=5000 log(g)= 1.0 [Fe/H]=-1 M= 1
Teff=5000 log(g)= 1.0 [Fe/H]=-1 M= 5
Teff=5000 log(g)= 1.0 [Fe/H]= 0 M= 1
Teff=5000 log(g)= 1.0 [Fe/H]= 0 M= 5
Teff=5000 log(g)= 2.0 [Fe/H]=-2 M= 1
Teff=5000 log(g)= 2.0 [Fe/H]=-1 M= 1
Teff=5000 log(g)= 2.0 [Fe/H]=-1 M= 5
Teff=5000 log(g)= 2.0 [Fe/H]= 0 M= 1
Teff=5000 log(g)= 2.0 [Fe/H]= 0 M= 5
Teff=5000 log(g)= 3.5 [Fe/H]= 0 M= 1
Teff=5500 log(g)= 0.0 [Fe/H]= 0 M= 1
Teff=5500 log(g)= 1.0 [Fe/H]=-2 M= 5
Teff=5500 log(g)= 1.0 [Fe/H]=-1 M= 1
Teff=5500 log(g)= 1.0 [Fe/H]= 0 M= 1
Teff=5500 log(g)= 2.0 [Fe/H]=-2 M= 1
Teff=5500 log(g)= 2.0 [Fe/H]=-1 M= 1
Teff=5500 log(g)= 2.0 [Fe/H]= 0 M= 1
Teff=5500 log(g)= 3.5 [Fe/H]= 0 M= 1
Teff=6000 log(g)= 1.0 [Fe/H]=-2 M= 1
Teff=6000 log(g)= 1.0 [Fe/H]=-2 M= 5
Teff=6000 log(g)= 1.0 [Fe/H]=-1 M= 1
Teff=6000 log(g)= 1.0 [Fe/H]=-1 M= 5
Teff=6000 log(g)= 1.0 [Fe/H]= 0 M= 1
Teff=6000 log(g)= 1.0 [Fe/H]= 0 M= 5
Teff=6000 log(g)= 2.0 [Fe/H]=-4 M= 1
Teff=6000 log(g)= 2.0 [Fe/H]=-1 M= 1
Teff=6000 log(g)= 2.0 [Fe/H]= 0 M= 1
Teff=6000 log(g)= 2.0 [Fe/H]= 0 M= 5
Teff=6000 log(g)= 3.5 [Fe/H]= 0 M= 1
Teff=6500 log(g)= 1.0 [Fe/H]=-2 M= 5
Teff=6500 log(g)= 1.0 [Fe/H]=-1 M= 1
Teff=6500 log(g)= 1.0 [Fe/H]= 0 M= 1
Teff=6500 log(g)= 2.0 [Fe/H]=-2 M= 1
Teff=6500 log(g)= 2.0 [Fe/H]= 0 M= 1
Teff=6500 log(g)= 3.5 [Fe/H]= 0 M= 1
Teff=7000 log(g)= 2.0 [Fe/H]=-1 M= 1
Teff=7000 log(g)= 2.0 [Fe/H]=-1 M= 5
Teff=7000 log(g)= 2.0 [Fe/H]= 0 M= 1
Teff=7000 log(g)= 2.0 [Fe/H]= 0 M= 5
Teff=7000 log(g)= 3.5 [Fe/H]=-1 M= 1
Teff=7500 log(g)= 2.0 [Fe/H]=-2 M= 1
Teff=7500 log(g)= 2.0 [Fe/H]=-1 M= 1
Teff=7500 log(g)= 2.0 [Fe/H]= 0 M= 1
Teff=7500 log(g)= 3.5 [Fe/H]=-1 M= 1
Teff=8000 log(g)= 2.0 [Fe/H]= 0 M= 1
Teff=8000 log(g)= 3.5 [Fe/H]=-2 M= 1
Teff=8000 log(g)= 3.5 [Fe/H]=-1 M= 1
Teff=8000 log(g)= 3.5 [Fe/H]= 0 M= 1
==============================
Plane Parallel Geometry,
log(g)=4.0 (50 models)
==============================
Teff=4000 [Fe/H]=-2
Teff=4000 [Fe/H]=-1
Teff=4000 [Fe/H]= 0
Teff=4000 [Fe/H]=0.5
Teff=4000 [Fe/H]= 1
Teff=4500 [Fe/H]=-4
Teff=4500 [Fe/H]=-2
Teff=4500 [Fe/H]=-1
Teff=4500 [Fe/H]= 0
Teff=4500 [Fe/H]=0.5
Teff=4500 [Fe/H]= 1
Teff=5000 [Fe/H]=-4
Teff=5000 [Fe/H]=-2
Teff=5000 [Fe/H]=-1
Teff=5000 [Fe/H]= 0
Teff=5000 [Fe/H]=0.5
Teff=5000 [Fe/H]= 1
Teff=5500 [Fe/H]=-4
Teff=5500 [Fe/H]=-2
Teff=5500 [Fe/H]=-1
Teff=5500 [Fe/H]= 0
Teff=5500 [Fe/H]=0.5
Teff=5500 [Fe/H]= 1
Teff=6000 [Fe/H]=-4
Teff=6000 [Fe/H]=-2
Teff=6000 [Fe/H]=-1
Teff=6000 [Fe/H]= 0
Teff=6000 [Fe/H]=0.5
Teff=6000 [Fe/H]= 1
Teff=6500 [Fe/H]=-4
Teff=6500 [Fe/H]=-2
Teff=6500 [Fe/H]=-1
Teff=6500 [Fe/H]= 0
Teff=6500 [Fe/H]=0.5
Teff=6500 [Fe/H]= 1
Teff=7000 [Fe/H]=-4
Teff=7000 [Fe/H]=-2
Teff=7000 [Fe/H]=-1
Teff=7000 [Fe/H]= 0
Teff=7000 [Fe/H]=0.5
Teff=7500 [Fe/H]=-1
Teff=7500 [Fe/H]= 0
Teff=7500 [Fe/H]=0.5
Teff=7500 [Fe/H]= 1
Teff=8000 [Fe/H]=-4
Teff=8000 [Fe/H]=-2
Teff=8000 [Fe/H]=-1
Teff=8000 [Fe/H]= 0
Teff=8000 [Fe/H]=0.5
Teff=8000 [Fe/H]= 1
===============================
Dwarfs (Plane Parallel Geometry):
===============================
Teff=6250 log(g)= +4.5 [Fe/H]=-3.00
Teff=6250 log(g)= +4.5 [Fe/H]=-4.00
Teff=6250 log(g)= +4.5 [Fe/H]=-5.00
===============================
Giants (Spherical Geometry):
===============================
Teff=5000 log(g)= +1.5 [Fe/H]=-3.00 M= 1.0
Teff=5000 log(g)= +1.5 [Fe/H]=-4.00 M= 1.0
Teff=5000 log(g)= +2.0 [Fe/H]=-3.00 M= 1.0
Teff=5000 log(g)= +2.0 [Fe/H]=-4.00 M= 1.0
Teff=5000 log(g)= +2.0 [Fe/H]=-5.00 M= 1.0
Upload Spectrum
Select...
Blackbody
Temperature:
K
Power Law
Index:
F(λ) ∝ λ
^{index}
Emission Line
Lambda:
nm
Flux:
10
-16
ergs/s/cm
2
(per arcsec
2
for extended sources)
FWHM:
nm
Spatial Distribution:
Point Source
Extended Source
Sky Conditions
Moon phase:
0
3
7
10
14
days
from new Moon
Airmass
:
Seeing/Image Quality:
The seeing and image quality are irrelevant for extended sources
For point sources, the resulting Image Quality FWHM is approximated by a gaussian in the ETC considering the transfer functions of the atmosphere, telescope and instrument. 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
Instrumental Setup
Resolution:
Standard
High
Grism:
GRIS_150I+27 (<650nm) Disp 23 nm/mm (0".345/pixel)
GRIS_150I+27 (>590nm,OG590) Disp 23.0 nm/mm (0".345/pixel)
GRIS_300V+10 (<650nm) Disp 11.2 nm/mm (0".168/pixel)
GRIS_300V+10 (>450nm,GG435) Disp 11.2 nm/mm (0".168/pixel)
GRIS_300I+11 Disp 10.8 nm/mm (0".345/pixel)
GRIS_300I+11 (>590 nm,OG590) Disp 10.8 nm/mm (0".345/pixel)
GRIS_600B+22 Disp 5.0 nm/mm (0".075/pixel)
GRIS_600RI+19 (GG435) Disp 5.5 nm/mm (0".083/pixel)
GRIS_600z+23 (OG590)Disp 5.4 nm/mm (0".081/pixel)
GRIS_1028z (OG590) Disp 2.85 nm/mm (0".084./pixel)
GRIS_1200B+97 Disp 2.40 nm/mm (0".036/pixel)
GRIS_1200R+93 (GG435) Disp 2.50 nm/mm(0".038/pixel)
GRIS_1400V+18 Disp 2.08 nm/mm (0".031/pixel)
=======================================================
NOTE! The following grisms are only available in Visitor Mode !
=======================================================
VM only: GRIS_600V+94 (GG435) Disp 4.9 nm/mm (0".074/pixel)
VM only: GRIS_1200g+96 Disp 2.43 nm/mm (0".036/pixel)
VM only: GRIS_600R+14 (GG435) Disp 4.5 nm/mm (0".068/pixel)
VM only: GRIS_600I+25 (OG590) Disp 4.4 nm/mm (0".066/pixel)
VM only: GRIS_200I+28 (OG550) Disp 16.2 nm/mm (0".243/pixel)
Slit:
0.28
0.40
0.51
0.70
1.00
1.31
1.60
2.00
2.50
arcsec
Detector
:
MIT red-optimized CCD
E2V blue-optimized CCD
Readout mode:
100kHz,2x2,high
100kHz,1x1,high
200kHz,2x2,low
Polarimetry:
No Polarimetry
Linear or Circular Polarisation
Results
S/N
:
Exposure Time
:
s
Plots:
Toggle All / No Plots
Observed Object+Sky Spectrum
Observed Object Spectrum
Sky Radiance Spectrum in physical units (ph/s/m2/micron/arcsec2)
Observed Sky Spectrum
Sky Transmission spectrum
Total Efficiency and Wavelength Range
Signal-to-noise
Input spectrum in physical units
2D simulated image
Send questions and comments to
usd-help@eso.org