Pith. sign in

REVIEW 4 major objections 4 minor 28 references

Comb-referenced Doppler-free spectrometry of the $^{200}$Hg and $^{202}$Hg intercombination line at 254 nm

T0 review · 4 major / 4 minor · reviewed 2026-08-12 · deepseek-v4-flash

Challenge this review Re-run · record.json Download PDF Read on arXiv ↗ Review JSON

Pith's one-line read Absolute frequencies of the 254 nm mercury intercombination line are measured to 8 and 15 kHz, yielding the most precise mercury isotope shift to date.

desk verdict Careful comb-referenced Hg spectroscopy with an order-of-magnitude improvement in line centers; the AC Stark extrapolation is the main soft spot and the unexplained 200Hg slope discrepancy with Ref. [9] needs to be addressed before the 8 kHz claim is taken at face value. read the letter →

arxiv 2411.17275 v1 pith:JABF5B4N submitted 2024-11-26 physics.atom-ph

Stefania Gravina , Naveed A. Chishti , Simona Di Bernardo , Eugenio Fasci , Antonio Castrillo , Athanasios Laliotis , Livio Gianfrani This is my paper · ORCID
classification physics.atom-ph
keywords mercuryintercombinationlinedeep-UVspectroscopywavelengthmodulationsaturatedabsorptionopticalfrequencycombACStarkshiftisotopeabsolutemeasurement
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

The paper reports absolute frequencies of the deep-ultraviolet intercombination line of two mercury isotopes, $^{200}$Hg and $^{202}$Hg, with combined uncertainties of 8 and 15 kHz, roughly twenty and seven times smaller than the best previous values. The measurement uses a comb-calibrated laser source at 254 nm, wavelength-modulated saturated absorption to see the sub-Doppler feature, and an extrapolation to zero laser intensity that removes the AC Stark shift. The resulting centers are $1181550972331(6)$ kHz and $1181545676761(14)$ kHz, from which the isotope shift is $5295570 \pm 15_{\rm stat} \pm 8_{\rm syst}$ kHz. This is the most accurate determination of this isotope shift reported so far, and it agrees with the earlier, much less precise value. Precise mercury isotope shifts matter because they can be used to extract nuclear properties and to search for new physics through King-plot analyses.

What carries the argument

The load-bearing object is the wavelength-modulated saturated-absorption signal: a pump beam is retroreflected through a mercury vapor cell to create a Lamb dip, and a 220 Hz sinusoidal frequency modulation with first-harmonic lock-in detection converts the dip into a dispersive line shape that is fitted with a wavelength-modulated Voigt function. The absolute frequency axis is set by locking the 1014.8 nm seed laser to a fiber frequency comb and quadrupling to 254 nm, giving $f_{\rm UV} = 4(f_{\rm beat} + m f_{\rm rep} + 2 f_{\rm ceo})$. To eliminate the light shift, line centers are recorded at several UV powers and extrapolated linearly against the square root of the peak-to-peak signal; the fitted slopes give AC Stark coefficients of $-2.8 \pm 0.5$ and $-2.2 \pm 0.8$ kHz per milliwatt per square centimeter for the two isotopes. A second essential element is the paired up-and-down scan protocol, which cancels the $\pm 57$ kHz finite-bandwidth shift predicted by the stepped-scan apparatus function.

What would settle it

Re-measure the $^{200}$Hg line center at UV intensities below 1 mW per square centimeter, where the fitted AC Stark correction would be below 3 kHz; if the extrapolated zero-intensity frequency differs from $1181550972331$ kHz by more than the quoted 8 kHz combined uncertainty, the assumed linear light-shift scaling is wrong. A complementary check is to compare this zero-intensity center with an independent laser-cooled mercury measurement of the same transition that is free of room-temperature collisions and light shifts.

Watch

Extended reading notes

Core claim

On the paper's own terms, the central discovery is that wavelength-modulated saturated absorption with a frequency-comb-referenced frequency axis can deliver absolute deep-UV line centers at the $10^{-12}$ relative level in a simple room-temperature vapor cell. The authors establish the two absolute frequencies and show that the dominant power-dependent perturbation is a negative AC Stark shift that scales linearly with local UV intensity; extrapolating the measured line center as a function of the square root of the peak-to-peak signal to zero signal removes it. They also validate a stepped-scan bandwidth correction that otherwise shifts the retrieved centers by $\pm 57$ kHz, and they account for pressure shifts, second-order Doppler shifts, and the unresolved recoil doublet. The result is a $^{200}$Hg--$^{202}$Hg isotope shift of $5295570 \pm 15_{\rm stat} \pm 8_{\rm syst}$ kHz, consistent with the earlier value of $5295413 \pm 110_{\rm stat} \pm 180_{\rm syst}$ kHz but more than an order of magnitude tighter.

Load-bearing premise

The zero-intensity line centers rest on the assumption that the AC Stark shift is the only power-dependent contribution and that it scales linearly with the local UV intensity, so extrapolating the line center versus the square root of the signal to zero power is unbiased.

Editorial extensions

If this is right

  • The $^{200}$Hg line center becomes $1181550972331(6)$ kHz, improving the previous uncertainty by more than a factor of 20.
  • The $^{202}$Hg line center becomes $1181545676761(14)$ kHz, improving the previous uncertainty by about a factor of 7.
  • The $^{200}$Hg--$^{202}$Hg isotope shift of $5295570 \pm 15_{\rm stat} \pm 8_{\rm syst}$ kHz is the most accurate reported to date and agrees with the earlier value of $5295413 \pm 110_{\rm stat} \pm 180_{\rm syst}$ kHz.
  • The demonstrated absolute accuracy at 254 nm provides a calibrated frequency reference for Doppler-broadening thermometry on mercury, supporting the practical realization of the redefined kelvin.
  • The measured AC Stark coefficients imply that future high-precision mercury spectroscopy must apply isotope-specific light-shift corrections rather than a single global coefficient.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • If the zero-intensity extrapolation is unbiased, the same apparatus should reach comparable precision on the other bosonic isotopes, $^{198}$Hg and $^{204}$Hg, and the resulting four-isotope King plot could tighten constraints on nuclear-volume and new-physics contributions beyond what current mercury data allow.
  • The isotope dependence of the measured AC Stark slopes is a testable prediction: an ab initio calculation of the dynamic polarizability of the $6s6p\,{}^3P_1$ state at 254 nm should reproduce the ratio of the two slopes, and a failure would point to an unaccounted UV transition or an intensity-calibration offset.
  • Because the light shift depends on local intensity, using a different beam waist should leave the per-unit-intensity AC Stark coefficient unchanged; verifying this would confirm the intensity calibration and the saturation model on which the extrapolation rests.
  • Applied to sub-micrometer mercury vapor cells, the same comb-referenced wavelength-modulated scheme could measure Casimir-Polder shifts by tracking the line center as the cell thickness approaches the wavelength, an extension the paper itself flags as a future direction.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

4 major / 4 minor

Summary. The manuscript reports absolute frequency measurements of the 6s^2 1S0 -> 6s6p 3P1 intercombination line of ^200Hg and ^202Hg, using a frequency-comb referenced, wavelength-modulated saturated absorption spectrometer in the deep UV. The obtained line centers are 1,181,550,972,331(6) kHz and 1,181,545,676,761(14) kHz, leading to a ^200Hg-^202Hg isotope shift of 5,295,570 ± 15_stat ± 8_syst kHz. The authors claim improvements by more than a factor of 20 and 7 in the absolute accuracy for the two isotopes compared to the previous best measurement. The experimental strategy includes paired up/down scans to cancel finite-bandwidth shifts, a power-dependence study to correct for the AC Stark shift, and a partial uncertainty budget.

Significance. If the quoted accuracy is correct, these are the most precise absolute frequency determinations for this transition and its isotope shift, with relative uncertainties of a few parts in 10^-12. The work is relevant to optical frequency metrology, isotope-shift-based new-physics searches, and Doppler thermometry. The paper has strengths: a detailed description of the finite-bandwidth correction with an analytical model confirmed by data, a comb-based absolute frequency chain, and an explicit AC Stark study over a power range. However, the central claim is sensitive to the AC Stark extrapolation procedure, which contains an unresolved inconsistency with the previous measurement for ^200Hg, and the uncertainty budget does not include a systematic term for the extrapolation model. These issues must be addressed before the stated accuracy can be accepted.

major comments (4)
  1. [AC Stark extrapolation (Fig. 3)] The zero-intensity center frequencies are derived from a linear fit of the fitted line centers versus x = sqrt(S_pp), based on the assumption that x is proportional to the local UV intensity I0 in the weak-saturation regime. The data extend to I0 ≈ 30 mW/cm^2 against a saturation intensity of ≈110 mW/cm^2 (I/I_sat ≈ 0.27). At this degree of saturation, the Lamb-dip amplitude is no longer strictly quadratic in I0, and power broadening modifies the WM-Voigt lineshape, so the assumption x ∝ I0 can fail at the few-percent level. Since the maximum AC Stark shift is about 84 kHz, a few-percent curvature in the x(I) relation would bias the intercept by several kHz, comparable to the quoted 8 kHz total uncertainty. The manuscript provides no quantitative test of the linearity, nor does it add a model uncertainty for this effect. I request an estimate of the nonlinearity, for example by fitting a quadratic term in x or by repeating the analysis with truncated power ranges.
  2. [AC Stark slope discrepancy] The paper reports an AC Stark slope of -2.8 ± 0.5 kHz/(mW/cm^2) for ^200Hg, which 'differs significantly from the estimate of Ref. [9]', while the ^202Hg slope agrees. This unexplained disagreement indicates that either the conversion from fitted peak-to-peak signal to local intensity, or the lineshape model used to extract the centers, is not fully controlled for at least one isotope. The authors should discuss possible causes (e.g., residual power-dependent line asymmetry, intensity calibration error, or saturation effects) and, if the cause cannot be identified, include this discrepancy as an additional systematic uncertainty in the zero-intensity frequency.
  3. [Uncertainty budget (Table I)] Table I lists Type A statistical uncertainties of 6 and 14 kHz for the two isotopes, and Type B contributions from frequency calibration (3 kHz) and pressure shift (5 kHz), giving combined uncertainties of 8 and 15 kHz. However, the 6/14 kHz Type A entry is the statistical uncertainty of the linear regression in Fig. 3 only; it does not include any systematic contribution from the AC Stark extrapolation model or from the 'proper calibration' of the peak-to-peak signal. Given that the AC Stark correction reaches 84 kHz, the absence of a systematic term for this correction makes the final uncertainty budget incomplete. Please add a conservative Type B component for the extrapolation and calibration, or justify why these are negligible.
  4. [Residual amplitude modulation] The wavelength-modulation detection at the first harmonic is sensitive to residual amplitude modulation, which can produce a power-dependent offset in the fitted center due to baseline distortion. The manuscript does not report any measurement or estimate of residual AM or its effect on the line centers. This should be quantified or bounded, since it could contribute at the kHz level.
minor comments (4)
  1. [Intensity calibration] The sentence 'After proper calibration of the peak-to-peak signal' is vague; please describe the calibration procedure explicitly, including how the fitted S_pp relates to the intensity in the beam waist.
  2. [Operating conditions] The paper does not state the vapor pressure at which the final line-center measurements were performed; only the temperature 24 °C appears in Appendix A. Please specify the operating conditions for the data in Fig. 3 and Table I.
  3. [Fig. 3 error bars] In Fig. 3, the vertical bars are said to result from error propagation of line fitting uncertainties 'and subsequent multiplication by a factor of 3'; please clarify whether the factor is applied to the standard deviation or to the variance, and why a factor of 3 is chosen.
  4. [Linewidth comparison] The statement that the observed width is close to the expected value of about 6 MHz, with a discrepancy 'probably due to an overestimation of the calculated Zeeman broadening effect', is not quantitative; please give the measured FWHM and the calculated Zeeman contribution separately.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity: absolute frequencies derive from an external comb reference and literature pressure-shift data, with the zero-power extrapolation a nuisance-parameter calibration rather than a construction of the result.

full rationale

The paper's central results—absolute line centers and the 200Hg–202Hg isotope shift—are not defined by their inputs. The frequency axis is tied to a GPS-disciplined optical frequency comb via Eq. (1), an external absolute reference; the comb order is fixed by a wavemeter measurement. Pressure-shift corrections use literature coefficients (Ref. [9] for Hg–Hg, Ref. [24] for He–Hg), not values fitted in this work. The zero-intensity centers are obtained by a weighted linear fit of fitted line centers versus sqrt(S_p-p), where S_p-p is the measured Lamb-dip signal amplitude. This is an extrapolation to remove the AC Stark shift, i.e., a calibration of a nuisance effect using the same dataset; the intercept is not equal to any fitted parameter by construction. Whether the linear-in-sqrt(S_p-p) model is unbiased at I/I_sat ≈ 0.27 is a legitimate correctness concern, but it is a model assumption, not a circular reduction. Self-citations (Refs. [14, 15, 18, 19, 21]) describe the apparatus and lineshape/bandwidth models; they are not invoked as the justification for the absolute frequency values, which are benchmarked against external data (Ref. [9]) and an external comb. No load-bearing step reduces to its own input, so no circularity is found.

Assumptions & free parameters 2 free parameters · 4 assumptions · 0 invented entities

The central claim rests on the comb calibration, the AC Stark extrapolation model, the pressure shift coefficients from the literature, and the WM-Voigt lineshape model. The two AC Stark slopes are fitted calibrations used in the zero-intensity extrapolation, but they are reported measurements rather than hidden assumptions.

free parameters (2)
  • AC Stark slope for 200Hg = -2.8 ± 0.5 kHz/(mW/cm2)
    Fit from line center versus sqrt(peak-to-peak signal) versus UV power (Fig. 3); used to extrapolate to zero intensity.
  • AC Stark slope for 202Hg = -2.2 ± 0.8 kHz/(mW/cm2)
    Same extrapolation procedure as for 200Hg; used to set the zero-intensity line center.
assumptions (4)
  • domain assumption The absolute UV frequency is exactly four times the comb-referenced NIR frequency (Eq. 1), with no residual phase offset from the two nonlinear doubling stages.
    Used to set the absolute frequency axis; standard for this laser system but not independently verified in this preprint.
  • domain assumption The AC Stark shift is the only power-dependent contribution and is linear in the local UV intensity, so the zero-intensity intercept from a linear regression in sqrt(peak-to-peak signal) is unbiased.
    Basis for the AC Stark extrapolation in Fig. 3; central to the accuracy claim.
  • domain assumption Pressure shift coefficients taken from Refs. [9] and [24], together with conservative residual-gas estimates, bound the pressure shift uncertainty to about 5 kHz.
    Used in the uncertainty budget (Table I); the residual gas content of the sealed cell is not directly measured.
  • standard math The wavelength-modulated Voigt profile from Ref. [20] correctly describes the observed sub-Doppler lineshape, so fit residuals do not indicate an unmodeled asymmetry that would shift the center.
    Basis for line-center retrieval from the dispersive WM spectra shown in Fig. 2.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Comb-referenced Doppler-free spectrometry of the $^{200}$Hg and $^{202}$Hg intercombination line at 254 nm." pith.science (2026). https://pith.science/paper/JABF5B4N

@misc{pith2026241117275,
  author       = {Pith},
  title        = {Pith review of: Comb-referenced Doppler-free spectrometry of the $^200$Hg and $^202$Hg intercombination line at 254 nm},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/JABF5B4N}},
  note         = {Machine review of arXiv:2411.17275}
}
abstract

We report on precision spectroscopy of the 6s$^2$ $^1$S$_0\to$6s6p $^3$P$_1$ intercombination line of mercury in the deep ultraviolet, by means of a frequency-comb referenced, wavelength-modulated, saturated absorption technique. This method allowed us to perform sub-Doppler investigations with an absolute frequency axis at 254 nm, while ensuring a relatively high signal-to-noise ratio. The absolute line center frequencies of the $^{200}$Hg and $^{202}$Hg bosonic isotopes were measured with a global uncertainty of 8 and 15 kHz (namely, 6.8$\times$10$^{-12}$ and 1.3$\times$10$^{-11}$, in relative terms), respectively, the statistical and systematic components being significantly reduced as compared to past determinations. This remarkable result was achieved also thanks to an in-depth study of the AC stark effect. Furthermore, we found the most accurate $^{200}$Hg-$^{202}$Hg isotope shift ever obtained before, namely, $5295570\pm15_{stat}\pm8_{syst}$ kHz.

Figures

Figures reproduced from arXiv: 2411.17275 by the authors.

Figure 1
Figure 1. FIG. 1. Sketch of the experimental setup. ECDL stands for external-cavity diode laser; OFCS, optical frequency comb [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 3
Figure 3. FIG. 3. Line centers as a function of the square root of the [PITH_FULL_IMAGE:figures/full_fig_p003_3.png] view at source ↗
Figure 4
Figure 4. FIG. 4. Finite bandwidth effect. Absolute line center fre [PITH_FULL_IMAGE:figures/full_fig_p005_4.png] view at source ↗

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

28 extracted references · 27 canonical work pages

  1. [9]

    Debierre, N

    V. Debierre, N. S. Oreshkina, I. A. Valuev, Z. Harman, and C. H. Keitel, Testing standard-model extensions with isotope shifts in few-electron ions, Phys. Rev. A 106, 062801 (2022)

    work page 2022

  2. [1]

    Calibrated frequency scans across the intercombination line were obtained by finely tuning the frep frequency while the ECDL was locked to the comb

    An analog lock-in amplifier was used to perform the first-harmonic synchronous detection of the probe beam intensity, thus leading to a dispersive signal in coinci- dence with the Lamb-dip. Calibrated frequency scans across the intercombination line were obtained by finely tuning the frep frequency while the ECDL was locked to the comb. A 6 1 2 -digit vol...

    work page 2022

  3. [2]

    Frugiuele, E

    C. Frugiuele, E. Fuchs, G. Perez, and M. Schlaffer, Con- straining new physics models with isotope shift spec- troscopy, Phys. Rev. D 96, 015011 (2017)

    work page 2017

  4. [3]

    V. V. Flambaum, A. J. Geddes, and A. V. Viatkina, Iso- tope shift, nonlinearity of King plots, and the search for new particles, Phys. Rev. A 97, 032510 (2018)

    work page 2018

  5. [4]

    W. H. King, Isotope shifts in atomic spectra (Springer Science & Business Media, 2013)

    work page 2013

  6. [5]

    M. D. Rayman, C. G. Aminoff, and J. L. Hall, Precise laser frequency scanning using frequency-synthesized op- tical frequency sidebands: application to isotope shifts and hyperfine structure of mercury, J. Opt. Soc. Am. B 6, 539 (1989)

    work page 1989

  7. [6]

    Gianfrani, A

    L. Gianfrani, A. Sasso, G. M. Tino, and M. Inguscio, Ex- perimental indication of a nuclear volume contribution to the isotope shift of atomic oxygen, Optics Communi- cations 78, 158 (1990)

    work page 1990

  8. [7]

    N. L. Figueroa, J. C. Berengut, V. A. Dzuba, V. V. Flam- baum, D. Budker, and D. Antypas, Precision determina- tion of isotope shifts in Ytterbium and implications for new physics, Phys. Rev. Lett. 128, 073001 (2022)

    work page 2022

Show all 28 references
  1. [8]

    J. Hur, D. P. L. Aude Craik, I. Counts, E. Knyazev, L. Caldwell, C. Leung, S. Pandey, J. C. Berengut, A. Geddes, W. Nazarewicz, P.-G. Reinhard, A. Kawasaki, H. Jeon, W. Jhe, and V. Vuleti´ c, Evidence of two-source King plot nonlinearity in spec- troscopic search for new boson...

    2022

  2. [10]

    Witkowski, G

    M. Witkowski, G. Kowzan, R. Munoz-Rodriguez, R. Ciury lo, P. S. ˙Zuchowski, P. Mas lowski, and M. Za- wada, Absolute frequency and isotope shift measure- ments of mercury 1S0 −3 P1 transition, Optics Express 27, 11069 (2019)

    2019

  3. [11]

    M. S. Safronova, D. Budker, D. DeMille, D. F. J. Kimball, A. Derevianko, and C. W. Clark, Search for new physics with atoms and molecules, Rev. Mod. Phys. 90, 025008 (2018)

    2018

  4. [12]

    J. J. McFerran, L. Yi, S. Mejri, S. Di Manno, W. Zhang, J. Gu´ ena, Y. Le Coq, and S. Bize, Neutral atom frequency reference in the deep ultraviolet with fractional uncertainty = 5 .7 × 10−15, Phys. Rev. Lett. 108, 183004 (2012)

    2012

  5. [13]

    Graner, Y

    B. Graner, Y. Chen, E. Lindahl, B. Heckel, et al. , Re- duced limit on the permanent electric dipole moment of 199Hg, Physical review letters 116, 161601 (2016)

    2016

  6. [14]

    E. J. Angstmann, V. A. Dzuba, and V. V. Flambaum, 6 Relativistic effects in two valence-electron atoms and ions and the search for variation of the fine-structure constant, Phys. Rev. A 70, 014102 (2004)

    2004

  7. [15]

    Clivati, S

    C. Clivati, S. Gravina, A. Castrillo, G. A. Costanzo, F. Levi, and L. Gianfrani, Tunable UV spectrometer for Doppler broadening thermometry of mercury, Optics Let- ters 45, 3693 (2020)

    2020

  8. [16]

    Gravina, C

    S. Gravina, C. Clivati, N. A. Chishti, A. Castrillo, E. Fasci, F. Bertiglia, G. Lopardo, A. Sorgi, N. Coluc- celli, G. Galzerano, P. C. Pastor, F. Levi, and L. Gian- frani, Comb-assisted mercury spectroscopy in the deep- ultraviolet: towards the development of a new pri- mary ...

    2023

  9. [17]

    Machin, The kelvin redefined, Measurement Science and Technology 29, 022001 (2018)

    G. Machin, The kelvin redefined, Measurement Science and Technology 29, 022001 (2018)

    2018

  10. [18]

    L. Gianfrani, Linking the thermodynamic temperature to an optical frequency: recent advances in Doppler broad- ening thermometry, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineer- ing Sciences 374, 20150047 (2016)

    2016

  11. [19]

    Gravina, C

    S. Gravina, C. Clivati, A. Castrillo, E. Fasci, N. Chishti, G. Galzerano, F. Levi, and L. Gianfrani, Measurement of the mercury (6s6p) 3P1-state lifetime in the frequency domain from integrated absorbance data, Physical Re- view Research 4, 033240 (2022)

    2022

  12. [20]

    Gambetta, E

    A. Gambetta, E. Vicentini, N. Coluccelli, Y. Wang, T. T. Fernandez, P. Maddaloni, P. De Natale, A. Cas- trillo, L. Gianfrani, P. Laporta, and G. Galzerano, Versa- tile mid-infrared frequency-comb referenced sub-Doppler spectrometer, APL Photonics 3, 046103 (2018)

    2018

  13. [21]

    Westberg, J

    J. Westberg, J. Wang, and O. Axner, Fast and non- approximate methodology for calculation of wavelength- modulated Voigt lineshape functions suitable for real- time curve fitting, Journal of Quantitative Spectroscopy and Radiative Transfer 113, 2049 (2012)

    2012

  14. [22]

    Rohart, S

    F. Rohart, S. Mejri, P. L. T. Sow, S. K. Tokunaga, C. Chardonnet, B. Darqui´ e, H. Dinesan, E. Fasci, A. Cas- trillo, L. Gianfrani, et al., Absorption-line-shape recovery beyond the detection-bandwidth limit: application to the precision spectroscopic measurement of the Boltzm...

    2014

  15. [23]

    F. Rohart, Overcoming the detection bandwidth limit in precision spectroscopy: The analytical apparatus func- tion for a stepped frequency scan, Journal of Quantitative Spectroscopy and Radiative Transfer 187, 490 (2017)

    2017

  16. [24]

    J. E. Stalnaker, D. Budker, S. J. Freedman, J. S. Guz- man, S. M. Rochester, and V. V. Yashchuk, Dynamic Stark effect and forbidden-transition spectral line shapes, Phys. Rev. A 73, 043416 (2006)

    2006

  17. [25]

    Lewis, Collisional relaxation of atomic excited states, line broadening and interatomic interactions, Physics Re- ports 58, 1 (1980)

    E. Lewis, Collisional relaxation of atomic excited states, line broadening and interatomic interactions, Physics Re- ports 58, 1 (1980)

    1980

  18. [26]

    Petersen, R

    M. Petersen, R. Chicireanu, S. T. Dawkins, D. V. Mag- alh˜ aes, C. Mandache, Y. Le Coq, A. Clairon, and S. Bize, Doppler-free spectroscopy of the 1S0−3P0 optical clock transition in laser-cooled fermionic isotopes of neutral mercury, Phys. Rev. Lett. 101, 183004 (2008)

    2008

  19. [27]

    J. S. Schelfhout and J. J. McFerran, Isotope shifts for 1S0 −3 P o 0,1 Yb lines from multiconfiguration Dirac- Hartree-Fock calculations, Phys. Rev. A 104, 022806 (2021)

    2021

  20. [28]

    Bureau International des Poids et Mesures (BIPM), Estimation of a consensus KCR V and associated degrees of equivalence, CCQM Guidance note https://www.bipm.org/documents/20126/28430045/working- document-ID-5794/49d366bc-295f-18ca-c4d3- d68aa54077b5 (2013)

    2013

Pith tools

Reviewed August 12, 2026 · model on record in the stance chip above.