J/ApJS/213/28 Spectrum analysis of CrII (Sansonetti+, 2014)
Extended analysis of the spectrum of singly ionized chromium (Cr II).
Sansonetti C.J., Nave G.
<Astrophys. J. Suppl. Ser., 213, 28 (2014)>
=2014ApJS..213...28S 2014ApJS..213...28S
ADC_Keywords: Atomic physics ; Spectra, ultraviolet
Keywords: atomic data; infrared: general; line: identification;
methods: laboratory: atomic; techniques: spectroscopic;
ultraviolet: general
Abstract:
We have made new observations of the spectrum of singly ionized
chromium (CrII) in the region 2850-37900Å with the National
Institute of Standards and Technology 2m Fourier transform
spectrometer. These data extend our previously reported observations
in the near-ultra-violet region. We present a comprehensive list of
more than 5300 CrII lines classified as transitions among 456 even
and 457 odd levels, 179 of which are newly located in this work. Using
highly excited levels of the 3d4(5D)5g, 3d4(5D)6g, and
3d4(5D)6h configurations, we derive an improved ionization energy
of 132971.02±0.12cm-1 (16.486305±0.000015eV).
Description:
Our new observations of the chromium spectrum were made using a
demountable water-cooled hollow cathode lamp with a solid chromium
cathode and flowing neon buffer gas. We determined empirically that
good excitation of CrII was obtained at a current of 2.0A and a neon
pressure of 400Pa (3.0torr). All new spectra analyzed in this work
were recorded at this current and pressure. We observed the spectrum
with the NIST 2m Fourier Transform Spectrometer (FTS). Three spectra
with observing parameters showned below were measured for this work:
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Spec Identifier Spectral Range Resolution Beam Splitter Detector
(cm^-1) (cm^-1)
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1 Cr061011.007 11800-35000 0.02 Fused Silica Si Photodiode
2 Cr071012.003 1850-17760 0.005 CaF InSb
3^a Cr041112.003 1850-19000 0.01 CaF InSb
Cr041112.004 1850-19000 0.01 CaF InSb
Cr041112.005 1850-19000 0.01 CaF InSb
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a= Three interferograms were co-added to produce spectrum 3.
---------------------------------------------------------------------------
Several additional spectra were recorded and used as comparison spectra.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 178 5359 Classified lines of CrII
table3.dat 65 913 Optimized energy levels of CrII
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See also:
J/ApJS/202/15 : UV spectrum of CrII (Sansonetti+, 2012)
J/ApJS/196/24 : Electron-impact excitation of CrII (Wasson+, 2011)
J/A+A/524/A35 : Effective collision strengths of CrII (Wasson+, 2010)
J/A+A/511/A68 : Transitions of CrII (Gurell+, 2010)
J/ApJ/700/720 : The 236.6-5400.0nm spectrum of CrI (Wallace+, 2009)
J/ApJ/667/1267 : CrI transition probabilities (Sobeck+, 2007)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- Int [1/10000] Intensity
7- 9 A3 --- f_Int Flags describing line character (1)
11- 22 F12.5 0.1nm lambda [1142/37857] Wavelength λ (Å) (2)
25- 31 F7.5 0.1nm e_lambda Uncertainty in lambda
35- 44 F10.4 cm-1 sigma [2641/87535] Wavenumber σ
47- 52 F6.4 cm-1 e_sigma [/0.4] Uncertainty in sigma
56- 66 F11.4 cm-1 E0 [0/115979] Lower level value
68 A1 --- --- [-] Dash to visually offset lower/upper levels
70- 80 F11.4 cm-1 E1 [46823/124524] Upper level value
84-105 A22 --- Conf0 Lower level configuration
108-112 A5 --- Term0 Lower level term
115-116 I2 --- 2J0 [1/17] Lower level J*2 value
117-118 A2 --- --- [/2]
120 A1 --- --- [-] Dash to visually offset even/odd sides
122-143 A22 --- Conf1 Upper level configuration
146-150 A5 --- Term1 Upper level term
153-154 I2 --- 2J1 [1/19] Upper level J*2 value
155-156 A2 --- --- [/2]
159-169 F11.5 0.1nm lam.c [1142/37857] Calculated wavelength (Å) (2)
172-178 F7.5 0.1nm e_lam.c Uncertainty in lam.c
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Note (1): Code as follows:
a = asymmetric
c = blend with line of CrI
h = blend on high side
l = blend on low side
n = blend with line of NeII
p = perturbed by close line
w = wide
x = extrapolated wavelength
# = omitted from level optimization
* = multiply classified
Note (2):
Vacuum wavelength for λ < 2000Å
Standard air wavelength for λ > 2000Å
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 22 A22 --- Conf Configuration
26- 30 A5 --- Term Term
33- 34 I2 --- 2J [1/19] J*2 value
35- 36 A2 --- --- [/2]
39- 49 F11.4 cm-1 E [0/124524] Energy level value
52- 57 F6.4 cm-1 e_E [/0.2]? Uncertainty in Energy
60- 61 I2 --- Num [1/68]? Number of lines observed for level
64- 65 A2 --- Notes Notes (1)
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Note (1): Note as follows:
n = New level
d = Revised designation
j = Revised J value
t = Typographical error in Sugar and Corliss corrected
u = Previously reported level not observed in this work
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 11-Sep-2014