J/MNRAS/390/733 FTS reference UV wavelengths of CrIII (Smillie+, 2008)
Reference ultraviolet wavelengths of Cr III measured by Fourier transform
spectrometry.
Smillie D.G., Pickering J.C., Smith P.L.
<Mon. Not. R. Astron. Soc., 390, 733-740 (2008)>
=2008MNRAS.390..733S 2008MNRAS.390..733S
ADC_Keywords: Atomic physics
Keywords: atomic data - line: identification - methods: laboratory
Abstract:
We report CrIII ultraviolet (UV) transition wavelengths measured using
a high-resolution Fourier transform spectrometer (FTS), for the first
time, available for use as wavelength standards. The doubly ionized
iron group element spectra dominate the observed opacity of hot B
stars in the UV, and improved, accurate, wavelengths are required for
the analysis of astronomical spectra. The spectrum was excited using a
chromium-neon Penning discharge lamp and measured with the Imperial
College vacuum ultraviolet FTS. 140 classified 3d34s-3d34p CrIII
transition lines, in the spectral range 38000 to 49000cm-1 (2632 to
2041Å), the strongest having wavelength uncertainties less than one
part in 107, are presented.
Description:
The Cr III spectrum was acquired in the wavenumber range 31596 to
63192cm-1, using the Imperial College (IC) VUV FTS, and a PDL as
light source. The spectral resolution used, 0.12cm-1, was sufficient
to fully resolve the Doppler broadened transition line profiles, for
which the average unblended full-width at half maximum (FWHM) was just
under 0.3cm-1.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 88 140 The classified Cr III transition linelist
observed by FTS
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 F4.2 [-] logInt Logarithm (to the base ten) of the integrated
intensity (in arbitrary units)
6- 10 F5.3 cm-1 FWHM Line full-width at half maximum
12- 14 I3 --- SNR Signal-to-noise ratio
16- 24 F9.4 0.1nm lam.air Air wavelength
26- 34 F9.4 0.1nm lam.vac Vacuum wavelength
36- 44 F9.3 cm-1 sigma Line wavenumber
46- 51 F6.3 cm-1 Dsigma Wavenumber difference
(sigmaobs-sigmaRitz) (1)
53- 57 F5.3 cm-1 e_sigma rms uncertainty on sigma
60- 84 A25 --- Trans Transition (Lower - Upper)
86- 88 A3 --- Note Note (2)
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Note (1): Wavenumber difference between the FTS observed wavCobs)
and the Ritz wavenumber from Ekberg (1997, Phys. Scr., 56, 141)
Note (2): Note provides additional information about the line, as follows:
II = blended or doubly identified with a Cr II line
III = blended or doubly identified with a Cr III line
G = centre-of-gravity (COG) line fit (otherwise least-squares fit to
Voigt profile)
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 27-Mar-2009