spectral_trace_list¶
SpectralTraceList¶
List of spectral trace geometries for the detector plane.
Should work in concert with an ApertureList (or ApertureMask) object and a DetectorList object
Spectral trace patterns are to be kept in a fits.HDUList
with one or
more fits.BinTableHDU
extensions, each one describing the geometry of a
single trace. The first extension should be a BinTableHDU
connecting
the traces to the correct Aperture
and ImagePlane
objects.
The fits.HDUList
objects can be loaded using one of these two keywords:
filename
: for on disk FITS files, orhdulist
: for in-memoryfits.HDUList
objects
The format and contents of the extensions in the HDUList (FITS file) object is listed below
Input Data Format¶
A trace list FITS file needs the following extensions:
0 : PrimaryHDU [header]
1 : BinTableHDU [header, data] : Overview table of all traces
2..N : BinTableHDU [header, data] : Trace tables. One per spectral trace
EXT 0 : PrimaryHDU¶
Required Header Keywords:
ECAT : int : Extension number of overview table. Normally 1
EDATA : int : Extension number of first Trace table. Normally 2
No data is required in this extension
EXT 1 : BinTableHDU : Overview of traces¶
No special header keywords are required in this extension
Required Table columns:
description : str : identifier of each trace
extension_id : int : which extension is each trace in
aperture_id : int : which aperture matches this trace (e.g. MOS / IFU)
image_plane_id : int : on which image plane is this trace projected
EXT 2 : BinTableHDU : Individual traces¶
Required header keywords: - EXTNAME : must be identical to the description in EXT 1
Recommended header keywords: - DISPDIR : “x” or “y” : dispersion axis. If not present, Scopesim tries
to determine this automatically; this may be unreliable in some cases.
Required Table columns: - wavelength : float : [um] : wavelength of monochromatic aperture image - s : float : [arcsec] : position along aperture perpendicular to trace - x : float : [mm] : x position of aperture image on focal plane - y : float : [mm] : y position of aperture image on focal plane
SpectralTraceListWheel¶
A Wheel-Effect object for selecting between multiple gratings/grisms.
See SpectralTraceList
for the trace file format description.
Parameters¶
- trace_list_nameslist
The list of unique identifiers in the trace filenames
- filename_formatstr
f-string
that directs scopesim to the folder containing the trace files. This can be a!-string
if the trace names are shared with other*Wheel
effect objects (e.g. aFilterWheel
). See examples.- current_trace_liststr
default trace file to use
- kwargskey-value pairs
Addition keywords that are passed to the
SpectralTraceList
objects See SpectralTraceList docstring
Examples¶
A simplified YAML file example taken from the OSIRIS instrument package:
alias: INST
name: OSIRIS_LSS
properties:
decouple_detector_from_sky_headers: True
grism_names:
- R300B
- R500B
- R1000B
- R2500V
effects:
- name: spectral_trace_wheel
description: grism wheel contining spectral trace geometries
class: SpectralTraceListWheel
kwargs:
current_trace_list: "!OBS.grating_name"
filename_format: "traces/LSS_{}_TRACE.fits"
trace_list_names: "!INST.grism_names"
- name: grating_efficiency
description: OSIRIS grating efficiency curves, piggybacking on FilterWheel
class: FilterWheel
kwargs:
minimum_throughput: !!float 0.
filename_format: "gratings/{}.txt"
current_filter: "!OBS.grating_name"
filter_names: "!INST.grism_names"