GST NIRIS 1565 nm 2021-02-05 Data Page |
Quick Look Movie of the 2021-02-05 NIRIS 1.565nm Data Set. The panels are Stokes I, Q, U, and V images.
NIRIS uses dual Fabry-Perot etalons that provide an 85 arcsec round field of view with an image scale of 0.083 arcsec/pixel. The primary line used by NIRIS is the Fe I 1565 nm doublet with a bandpass of 0.01 nm. More than 60 line positions are typically scanned.
The available data set includes a number of fits files containing a 4D data cube {x,y,lambda,Stokes}.
Some important FITS header keywords:
CDELT1 & CDELT2: | the plate scale in arcsec/pixel |
STARTWV: | starting wavelength (Ang) counted from REFWV; Indicates the beginning of the scanned range |
ENDWV: | ending wavelength in (Ang) counted from REFWV; Indicates the end of the scanned range |
REFWV: | reference wavelength |
LCEN: | index position of the reference wavelength along NAXIS3 |
INCWV: | increment per wavelength (step along the spectra, Ang) |
so that NAXIS3=(ENDWV-STARTWV)/INCWV.