Instruments¶

GalPaK uses a virtual Instrument
to convolve the simulation cubes and check against observed data.
As each instrument has its own tweaks and quirks (both hardware and atmospheric),
you can provide an instrument to GalPaK3D
,
the default one being MUSE
in Wide Field Mode :
The spectral characteristics (pixel cdelt, etc.) are re-calibrated using the Cube’s header when you instantiate GalPaK.
Pay attention in defining most appropriate values for the seeing or psf_fwhm(“)
– psf_ba if not round – and lsf_fwhm (in units of cube) parameters.
All of them by default use the gaussian PSF GaussianPointSpreadFunction
.
Instruments handling¶
You should define the instrument as :
from galpak import GalPaK3D, MUSE, GaussianPointSpreadFunction
mypsf = GaussianPointSpreadFunction(fwhm=0.7,pa=0,ba=1)
myinstr = MUSE(psf=mypsf,lsf=None)
gk = GalPaK3D('GalPaK_cube_1101_from_paper.fits',instrument=myinstr)
And print(gk.instrument)
should yield
Note
The galpak save
method will save a file instrument.txt
If the instrument is saved into a instrument.txt file, one can use :
from galpak import GalPaK3D
gk = GalPaK3D('GalPaK_cube_1101_from_paper.fits',instrument='instrument.txt')
The file instrument.txt should be like :
Note
Both instrument.txt and model.txt can be combined in a single config file
Instruments supported¶
- ALMA
set lsf_fwhm to 1 cdelt (default) or less or use NoLineSpreadFunction
- SINFONI (J250, H250 and K250 modes)
SINFOJ250, SINFOH250, SINFOK250 :
- from galpak import run, SINFOK250
gk = run(‘my_sinfok250_cube.fits’, instrument=SINFOK250())
- MUSE (WFM and NFW modes)
default lsf_fwhm is 2.67 Angstrom
- KMOS
default xy_step is 0.2 arcsecs
- HARMONI
use the syntax HARMONI(pixscale=30)
OSIRIS
MANGA (soon)
Note
The default Instrument values will be overridden by the cube header info (CRPIX, CDELT etc.) if present.