An atlas of an aging Photron lamp used in FIES

  • Bottom panel. Red: a ThAr spectrum of the lamp after fresh install.

  • Middle panel. Ochre: a ThAr spectrum of the lamp after about 12 weeks use.

  • Top panel. Purple: another ThAr spectrum of the lamp taken on the same night as used for the middle panel.

  • The faint-coloured spectra are the above-described ones x10 in flux.

  • The spectra are flatfielded, including blaze-function correction, which means that the relative strength of the lines is different than for raw spectra.

  • The spectra are scaled to have unity flux in the 4765Å line.

  • Two ThAr line lists are indicated in the plots.
       The general IRAF ThAr list is indicated with small vertical markers.
       The FIEStool ThAr list is depicted with taller markers, and list-wavelengths are displayed when hovering these markers.
       Only those lines accepted for the wavelength solution of the Red spectrum (FIDk040003.fits), depicted by a circle on top of the tall marker, will display their wavelengths.

  • The lamp was installed 2020-11-03, and dismissed 2021-02-24

    3700-4000 Å

    4000-4500 Å

    4500-5000 Å

    5000-5500 Å

    5500-6000 Å

    6000-6500 Å

    6500-7000 Å

    7000-7500 Å

    7500-8000 Å

    8000-8500 Å

    8500-9000 Å

    Observations

  • An aged Photron lamp shows a much more variable spectrum, than a fresh lamp.

  • Strong lines from the fresh-lamp wavelength solution that are less than half their initial strength in both aged spectra:
       3719.4, 3828.4, 3929.7, 4019.1, 4493.3, 4919.8, 5068.0, 5158.6, 5231.2, 5343.6, 5499.3, 5587.0,
       5615.3, 5760.6, 5804.1, 5973.7, 6037.7, 6182.6, 6207.2, 6531.3, 7979.0, 8186.9, 8573.1, 8967.6

  • Clear lines from the fresh-lamp wavelength solution that are stronger than their initial strength in both aged spectra:
       4158.6, 4200.7, 4510.7, 5606.7, 5650.7, 5912.1, 6032.1, 6043.2, 6307.7, 6384.7, 6416.3,
       6677.3, 6752.8, 6871.3, 6937.7, 7373.1, 7353.3, 7435.4, 7891.1, 8053.3, 8384.7, 8667.9 (!)

  • There are many strong 'new' lines in the aged-lamp spectra, that do not correspond to any of the listed ThAr lines. These may not be Th or Ar lines.