SCIP - data structure description
Overview
The most relevant keywords are listed in the table below:
| Key | Value Type | Description |
|---|---|---|
DATE_OBS |
Date Time | UTC Acquisition Time |
In a future release, also WCS header fields will be provided.
Slit Jaw Imager (SJ)
The slit-jaw image data are not yet available.
Spectro-polarimeter (SP)
The SCIP SP data are provided in a single FITS file per slit position with wavelength, spatial (along slit) axis. In addition to the general header keywords above, the most relevant header keywords for SP data are:
In addition to the general header keywords above, the most relevant header keywords for SP data are:
| Key | Value Type | Description |
|---|---|---|
CDELT1 |
float | (angstrom) wavelength scale |
CRPIX1 |
int | Reference pixel on axis 1 |
CRVAL1 |
float | (angstrom) Coordinate value at the reference pixel |
CDELT2 |
float | (arcsec) spatial scale |
For further details on data descriptions and FITS keywords, please visit the SCIP Data Description & Keywords overview in the SCIP wiki.
Data Access Examples
Below we show a minimalistic python script to assemble traditional 4D cubes from the provided SP data and extract the linear wavelength axis in Angstrom:
from astropy.io import fits
import numpy as np
with fits.open("/path/to/SCIP.fits") as hdul:
header = hdul[0].header
data = hdul[0].data.copy()
nx,nw = data.shape
# Create wavelength axis in angstrom
wl = (np.arange(0,nw)-header["CRPIX1"])*header["CDELT1"] + header["CRVAL1"]
# Create spatial axis in arcsec
x = np.arange(0,nx)*header["CDELT2"]
SCIP
SCIP instrument publications
SCIP major spectral lines
