The V = 0 - 0 spectrum of H2

Jennings, D. E.; Bragg, S. L.; Brault, J. W.

doi:10.1086/184311

Cited by 43 publications

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“…This suggests that the determination of transition frequencies is more accurate than follows from the evaluation of the error budget for these pairs of lines. A statistical analysis yields a value for the combination difference of 354.3720(23) cm −1 , in agreement with the IR data (36). A similar procedure can be performed for the R( Table 8.…”

Section: Results Discussion and Conclusionsupporting

confidence: 77%

“…In Tables 2 and 3 (18), but rather the experimentally deduced values of the level energies, which relate to an average over emission lines in various bands (16). We converted these values into transition frequencies of the Lyman and Werner bands by adding the most accurate values for the level energies of X 1 + g , v" = 0 rotational states (36). The transition frequencies of the Meudon analysis are found to be higher by 0.06 cm −1 on average, with some scatter that has a standard deviation of 0.047 cm −1 .…”

Section: Results Discussion and Conclusionmentioning

confidence: 99%

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Frequency-mixing scheme for the production of tunable narrowband XUV radiation (91–95 nm): application to precision spectroscopy and predissociation in diatomic molecules

et al. 2004

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(v , 0) Werner bands for v = 0-4, using a narrow-band tunable extreme UV laser source at wavelengths λ = 92-105 nm in conjunction with the technique of 1 + 1 two-photon ionization. The measurements can be divided into three categories for which varying absolute accuracies were obtained. Special focus was on the B, v = 2-5 bands, where an accuracy of 0.004 cm −1 or δν/ν = 4 × 10 −8 is achieved. For transitions to B, v ≤ 13 and C, v ≤ 3 states the accuracy is 0.005 cm −1 or δν/ν = 5 × 10 −8 . Due to a different frequency mixing scheme uncertainties for B, v ≥ 13 and C, v = 4 are at the level of 0.011 cm −1 or δν/ν = 1.1 × 10 −7 . Inspection of combination differences between R(J ) and P(J + 2) lines shows that the accuracies are even better than estimated in the error budget. Based on the measurements of 138 spectral lines and the known combination differences, transition frequencies of 60 P-lines could be calculated as well, so that a data base of 198 accurately calibrated lines results for the Lyman and Werner bands of H 2 .Key words: vacuum UV, molecular spectroscopy, hydrogen, precision metrology. . Un examen des différences des combinaisons entre les raies R(J ) et P(J + 2) montre que les précisions sont meilleures que celles évaluées dans le budget des erreurs. Sur la base de mesures de 138 raies spectrales et de différences de combinaison connues, on a pu aussi calculer les fréquences de transition de 60 raies P et il en résulte qu'une base de données de 198 raies bien calibrées est disponible pour les bandes de Lyman et de Werner du H 2 .

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Section: Results Discussion and Conclusionsupporting

confidence: 77%

Section: Results Discussion and Conclusionmentioning

confidence: 99%

Frequency-mixing scheme for the production of tunable narrowband XUV radiation (91–95 nm): application to precision spectroscopy and predissociation in diatomic molecules

et al. 2004

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“…The ionization energy E i ͑H 2 ͒ and the dissociation energy D 0 ͑H 2 ͒ of para-H 2 can also be derived from this new measurement by including previous results on the ionization energy of the hydrogen atom, 7 the dissociation energy of H 2 + , 4 and the rotational energy level intervals for the lowest vibronic states of the neutral molecule and the cation. [8][9][10][11] …”

Section: Introductionmentioning

confidence: 99%

Determination of the ionization and dissociation energies of the hydrogen molecule

Liu

Salumbides²,

Hollenstein³

et al. 2009

The Journal of Chemical Physics

188

193

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The transition wave number from the EF 1 ⌺ g + ͑v =0,N =1͒ energy level of ortho-H 2 to the 54p1 1 ͑0͒ Rydberg state below the X + 2 ⌺ g + ͑v + =0,N + =1͒ ground state of ortho-H 2 + has been measured to be 25 209.997 56Ϯ ͑0.000 22͒ statistical Ϯ ͑0.000 07͒ systematic cm −1 . Combining this result with previous experimental and theoretical results for other energy level intervals, the ionization and dissociation energies of the hydrogen molecule have been determined to be 124 417.491 13͑37͒ and 36 118.069 62͑37͒ cm −1 , respectively, which represents a precision improvement over previous experimental and theoretical results by more than one order of magnitude. The new value of the ionization energy can be regarded as the most precise and accurate experimental result of this quantity, whereas the dissociation energy is a hybrid experimental-theoretical determination.

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“…The present data set can be used to calculate wavelengths for additional nonmeasured lines via the known ground state rotational splittings [18]: J 2 ÿ J 0 354:3734 2 cm ÿ1 , 3 ÿ 1 587:0325 2 cm ÿ1 , a n d 4 ÿ 2 814:4246 3 cm ÿ1 . This procedure provides wavelengths for ten lines, also listed in Table I, at an accuracy improved by an order of magnitude compared to the Meudon data set.…”

mentioning

confidence: 99%

“…For the remainder of the lines, not accessed in the present experimental study, we rely on the most accurate published values. We note that higher accuracy transition wavelengths can be derived from the excited state energies from the Meudon study [19], which are an average over many emission lines; these level energies can be converted into transition frequencies by adding highly accurate ground state rotational level energies of Jennings et al [18].…”

mentioning

confidence: 99%

Highly AccurateH2Lyman and Werner Band Laboratory Measurements and an Improved Constraint on a Cosmological Variation of the Proton-to-Electron Mass Ratio

Ubachs

Reinhold

2004

Phys. Rev. Lett.

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Transition wavelengths on a large set of H 2 Lyman and Werner band spectral lines have been obtained at an accuracy of 5 10 ÿ8 , using a narrow band tunable extreme ultraviolet laser. The data are used to determine a constraint on a possible cosmological variation of the proton-to-electron mass ratio ( M p =m e ) from a comparison with highly redshifted spectral data of quasistellar objects, yielding a fractional change in the mass ratio of = ÿ0:5 3:6 10 ÿ5 (2 ), which would correspond to a temporal change of d=dt = ÿ0:4 3:0 10 ÿ15 per year (2 ) if a linear cosmological expansion model is assumed. DOI: 10.1103/PhysRevLett.92.101302 PACS numbers: 98.80.Es, 14.20.Dh, 33.20.Ni, 98.62.Ra The search for a cosmological variability of fundamental physical constants has become an active field of research now that accurate spectroscopic data can be obtained from quasars that have emitted their radiation more than ten billion years ago. A comparison between laboratory data, obtained at the highest accuracy in the modern epoch, and analysis of corresponding redshifted spectra from distant objects allows for stringent constraints on variability of the physical constants underlying the spectra. One such issue is that of the fine structure constant , which was claimed to vary based on observations of quasar spectra [1]. Another is that of the proton-to-electron mass ratio M p =m e , a dimensionless parameter equalling 1836.152 672 61(85) [2]. The idea that fundamental physical constants might not be constant on a cosmological time scale was pioneered by Dirac, Teller, Gamov, and others; the observational status and theoretical perspectives were recently discussed by Uzan [3], citing all relevant publications.The spectrum of molecular hydrogen with the prominent Lyman and Werner band systems may be used to detect a change in over time, because each individual spectral line depends in a different way on the mass ratio, as was pointed out by Thompson [4]. In recent years, several observations have been made on the Lyman and Werner bands in quasars, taking advantage of the fact that Earth's atmosphere is transparent for these spectral regions at high z, and that ground-based echelle-grating spectrometers can be employed in high-resolution studies [5][6][7][8][9][10]. In comparisons, the laboratory data of the Lyman and Werner band tables of the Meudon group were used [11,12], which represent an extensive and accurate database. Nevertheless, it was emphasized that improved spectroscopic data are desired [8], because the statistical errors from astronomical and laboratory data contributed equally in the estimates of = , the fractional variation of . This is illustrated by the fact that Ivanchik et al. [8] find rather different constraints on = , when comparing quasar data with different laboratory data sets [11][12][13]. Here we report on laser-based laboratory determinations of Lyman and Werner band spectral lines at an accuracy improved by more than an order of magnitude; the resulting laboratory wavelengths 0 i can be consid...

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The V = 0 - 0 spectrum of H2

Cited by 43 publications

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Frequency-mixing scheme for the production of tunable narrowband XUV radiation (91–95 nm): application to precision spectroscopy and predissociation in diatomic molecules

Frequency-mixing scheme for the production of tunable narrowband XUV radiation (91–95 nm): application to precision spectroscopy and predissociation in diatomic molecules

Determination of the ionization and dissociation energies of the hydrogen molecule

Highly AccurateH2Lyman and Werner Band Laboratory Measurements and an Improved Constraint on a Cosmological Variation of the Proton-to-Electron Mass Ratio

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