We study the new $Z'$ boson as a portal for the production of Higgs bosons $h_0$ and $H_0$ predicted by the Bestest Little Higgs Model through Higgs-strahlung processes $\mu^+\mu^- \to (Z, Z') \to Zh_0, ZH_0$ . We focus on the resonant and nonresonant effects of the $Zh_0, ZH_0$ signals. In our analysis, we consider the center-of-mass energies of $\sqrt{s}=3, 4, 6, 10, 30$ TeV and integrated luminosities of ${\cal{L}}=2, 4, 6, 10, 30$ ${ {\rm{ab}}^{-1}}$ projected for a future muon collider. The possibility of performing precision measurements for Higgs bosons $h_0$ and $H_0$ is very promising for the future muon collider. Furthermore, our results may be useful to the High Energy Physics community. Complementarily, we generate and provide the Feynman rules necessary for studying processes $\mu^+\mu^- \to (Z, Z') \to Zh_0, ZH_0$ .

J.M. Martínez-Martínez

A. Gutiérrez-Rodríguez

E. Cruz-Albaro

M.A. Hernández-Ruíz

New $\textit{Z}$' boson of the bestest little Higgs model as a portal to signatures of Higgs bosons $\textit{h}$ $_{0}$ and $\textit{H}$ $_{0}$ at the future muon collider

An <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>SU</mi></mrow><mo stretchy="false">(</mo><mn>8</mn><mo stretchy="false">)</mo></math> theory was previously found to be the minimal simple gauge group where all three-generational Standard Model (SM) fermions can be nontrivially embedded. It is maximally broken into a subgroup of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>SU</mi></mrow><mo stretchy="false">(</mo><mn>8</mn><mo stretchy="false">)</mo><mo stretchy="false">→</mo><msub><mi mathvariant="script">G</mi><mn>441</mn></msub><mo>≡</mo><mrow><mi>SU</mi></mrow><mo stretchy="false">(</mo><mn>4</mn><msub><mo stretchy="false">)</mo><mi>s</mi></msub><mo stretchy="false">⊗</mo><mrow><mi>SU</mi></mrow><mo stretchy="false">(</mo><mn>4</mn><msub><mo stretchy="false">)</mo><mi>W</mi></msub><mo stretchy="false">⊗</mo><mi mathvariant="normal">U</mi><mo stretchy="false">(</mo><mn>1</mn><msub><mo stretchy="false">)</mo><msub><mi>X</mi><mn>0</mn></msub></msub></math> at the grand unified theory scale by the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>SU</mi></mrow><mo stretchy="false">(</mo><mn>8</mn><mo stretchy="false">)</mo></math> adjoint Higgs field of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn mathvariant="bold">6</mn><msub><mn mathvariant="bold">3</mn><mi mathvariant="bold">H</mi></msub></mrow></math>. Gauge symmetries in the strong and the weak sectors are extended by one and two ranks, respectively. The sequential strong-weak-weak (SWW) symmetry breaking stages were found to generate the observed hierarchical SM quark/lepton masses as well as the Cabibbo-Kobayashi-Maskawa mixing pattern with the precise flavor identifications [The global <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi mathvariant="normal">B</mi><mo stretchy="false">−</mo></mrow></math> L symmetry in the flavor-unified SU(N) theories, <a href="http://dx.doi.org/10.1007/JHEP04(2024)046">J. High Energy Phys. 04 (2024) 046</a>. and The standard model quark/lepton masses and the Cabibbo-Kobayashi-Maskawa mixing in an SU(8) theory, <a href="http://dx.doi.org/10.1007/JHEP12(2024)137">J. High Energy Phys. 12 (2024) 137</a>.]. We further study the possible weak-strong-weak and weak-weak-strong symmetry breaking patterns and compare with the results that we have obtained by following the SWW sequence. The two-loop renormalization group equations following both patterns are analyzed, where we cannot achieve the gauge coupling unification in the field theory framework. Through these analyses, we suggest the gauge coupling unification to be interpreted in the context of the affine Lie algebra.

China

Ning Chen

Zhiyuan Chen

Zhanpeng Hou

Zhaolong Teng

Bin Wang

Further study of the maximally symmetry breaking patterns in an <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>SU</mi></mrow><mo stretchy="false">(</mo><mn>8</mn><mo stretchy="false">)</mo></math> theory

We present a measurement of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">|</mo><msub><mi>V</mi><mrow><mi>u</mi><mi>b</mi></mrow></msub><mo stretchy="false">|</mo></math> from a simultaneous study of the charmless semileptonic decays <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mi>B</mi></mrow><mrow><mn>0</mn></mrow></msup><mo stretchy="false">→</mo><msup><mrow><mi>π</mi></mrow><mrow><mo>−</mo></mrow></msup><msup><mrow><mo>ℓ</mo></mrow><mrow><mo>+</mo></mrow></msup><msub><mrow><mi>ν</mi></mrow><mrow><mo>ℓ</mo></mrow></msub></mrow></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mi>B</mi></mrow><mrow><mo>+</mo></mrow></msup><mo stretchy="false">→</mo><msup><mrow><mi>ρ</mi></mrow><mrow><mn>0</mn></mrow></msup><msup><mrow><mo>ℓ</mo></mrow><mrow><mo>+</mo></mrow></msup><msub><mrow><mi>ν</mi></mrow><mrow><mo>ℓ</mo></mrow></msub></mrow></math>, where <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo>ℓ</mo><mo>=</mo><mi>e</mi></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>μ</mi></mrow></math>. This measurement uses a data sample of 387 million <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>B</mi><mover accent="true"><mi>B</mi><mo stretchy="false">¯</mo></mover></math> meson pairs recorded by the Belle II detector at the SuperKEKB electron-positron collider between 2019 and 2022. The two decays are reconstructed without identifying the partner <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>B</mi></math> mesons. We simultaneously measure the differential branching fractions of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mn>0</mn></msup><mo stretchy="false">→</mo><msup><mi>π</mi><mo>−</mo></msup><msup><mo>ℓ</mo><mo>+</mo></msup><msub><mi>ν</mi><mo>ℓ</mo></msub></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mo>+</mo></msup><mo stretchy="false">→</mo><msup><mi>ρ</mi><mn>0</mn></msup><msup><mo>ℓ</mo><mo>+</mo></msup><msub><mi>ν</mi><mo>ℓ</mo></msub></math> decays as functions of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>q</mi><mn>2</mn></msup></math> (momentum transfer squared). From these, we obtain total branching fractions <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi mathvariant="script">B</mi><mo stretchy="false">(</mo><msup><mrow><mi>B</mi></mrow><mrow><mn>0</mn></mrow></msup><mo stretchy="false">→</mo><msup><mrow><mi>π</mi></mrow><mrow><mo>−</mo></mrow></msup><msup><mrow><mo>ℓ</mo></mrow><mrow><mo>+</mo></mrow></msup><msub><mrow><mi>ν</mi></mrow><mrow><mo>ℓ</mo></mrow></msub><mo stretchy="false">)</mo><mo>=</mo><mo stretchy="false">(</mo><mn>1.516</mn><mo>±</mo><mn>0.042</mn><mo stretchy="false">(</mo><mrow><mi>stat</mi></mrow><mo stretchy="false">)</mo><mo>±</mo><mn>0.059</mn><mo stretchy="false">(</mo><mrow><mi>syst</mi></mrow><mo stretchy="false">)</mo><mo stretchy="false">)</mo><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>4</mn></mrow></msup></mrow></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi mathvariant="script">B</mi><mo stretchy="false">(</mo><msup><mrow><mi>B</mi></mrow><mrow><mo>+</mo></mrow></msup><mo stretchy="false">→</mo><msup><mrow><mi>ρ</mi></mrow><mrow><mn>0</mn></mrow></msup><msup><mrow><mo>ℓ</mo></mrow><mrow><mo>+</mo></mrow></msup><msub><mrow><mi>ν</mi></mrow><mrow><mo>ℓ</mo></mrow></msub><mo stretchy="false">)</mo><mo>=</mo><mspace linebreak="goodbreak"></mspace><mo stretchy="false">(</mo><mn>1.625</mn><mo>±</mo><mn>0.079</mn><mo stretchy="false">(</mo><mrow><mi>stat</mi></mrow><mo stretchy="false">)</mo><mo>±</mo><mn>0.180</mn><mo stretchy="false">(</mo><mrow><mi>syst</mi></mrow><mo stretchy="false">)</mo><mo stretchy="false">)</mo><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>4</mn></mrow></msup></mrow></math>. By fitting the measured <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mn>0</mn></msup><mo stretchy="false">→</mo><msup><mi>π</mi><mo>−</mo></msup><msup><mo>ℓ</mo><mo>+</mo></msup><msub><mi>ν</mi><mo>ℓ</mo></msub></math> partial branching fractions as functions of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>q</mi><mn>2</mn></msup></math>, together with constraints on the nonperturbative hadronic contribution from lattice QCD calculations, we obtain <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">|</mo><msub><mi>V</mi><mrow><mi>u</mi><mi>b</mi></mrow></msub><mo stretchy="false">|</mo><mo>=</mo><mo stretchy="false">(</mo><mn>3.93</mn><mo>±</mo><mn>0.09</mn><mo>±</mo><mn>0.13</mn><mo>±</mo><mn>0.19</mn><mo stretchy="false">)</mo><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>3</mn></mrow></msup></math>. Here, the first uncertainty is statistical, the second is systematic, and the third is theoretical.

I. Adachi

L. Aggarwal

H. Aihara

N. Akopov

A. Aloisio

N. Althubiti

N. Anh Ky

D.M. Asner

H. Atmacan

T. Aushev

V. Aushev

M. Aversano

R. Ayad

V. Babu

H. Bae

S. Bahinipati

P. Bambade

Sw. Banerjee

S. Bansal

M. Barrett

J. Baudot

M. Bauer

A. Baur

A. Beaubien

F. Becherer

J. Becker

J.V. Bennett

F.U. Bernlochner

V. Bertacchi

M. Bertemes

E. Bertholet

M. Bessner

S. Bettarini

B. Bhuyan

F. Bianchi

L. Bierwirth

T. Bilka

D. Biswas

A. Bobrov

D. Bodrov

A. Bolz

J. Borah

A. Boschetti

A. Bozek

M. Bračko

P. Branchini

R.A. Briere

T.E. Browder

A. Budano

S. Bussino

Q. Campagna

M. Campajola

L. Cao

G. Casarosa

C. Cecchi

J. Cerasoli

M.C. Chang

P. Chang

R. Cheaib

P. Cheema

B.G. Cheon

K. Chilikin

K. Chirapatpimol

H.E. Cho

K. Cho

S.J. Cho

S.K. Choi

S. Choudhury

L. Corona

J.X. Cui

F. Dattola

E. De La Cruz-Burelo

S.A. De La Motte

G. De Nardo

M. De Nuccio

G. De Pietro

R. de Sangro

M. Destefanis

S. Dey

R. Dhamija

A. Di Canto

F. Di Capua

J. Dingfelder

Z. Doležal

I. Domínguez Jiménez

T.V. Dong

M. Dorigo

D. Dorner

K. Dort

D. Dossett

S. Dreyer

S. Dubey

K. Dugic

G. Dujany

P. Ecker

M. Eliachevitch

P. Feichtinger

T. Ferber

T. Fillinger

C. Finck

Determination of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">|</mo><msub><mi>V</mi><mrow><mi>u</mi><mi>b</mi></mrow></msub><mo stretchy="false">|</mo></math> from simultaneous measurements of untagged <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mn>0</mn></msup><mo stretchy="false">→</mo><msup><mi>π</mi><mo>−</mo></msup><msup><mo>ℓ</mo><mo>+</mo></msup><msub><mi>ν</mi><mo>ℓ</mo></msub></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mo>+</mo></msup><mo stretchy="false">→</mo><msup><mi>ρ</mi><mn>0</mn></msup><msup><mo>ℓ</mo><mo>+</mo></msup><msub><mi>ν</mi><mo>ℓ</mo></msub></math> decays

We calculate the perturbative corrections in the strong coupling to the unpolarized quark transverse-momentum dependent parton distribution function (TMDPDF) operator within a background-field framework, extending the approach of Mukherjee et al. [<a href="http://dx.doi.org/10.1103/PhysRevD.109.034035">Phys. Rev. D 109, 034035 (2024)</a>]. We focus on ensuring gauge invariance, identifying two key components needed: a gauge-invariant TMDPDF operator with a transverse gauge link at spatial infinity, and accounting of the equations of motion (EoM) of the background fields. We go beyond next-to-leading order in strong coupling expansion, considering multiple interactions with the background field at all orders of strong coupling. By examining the interplay between quark and gluon contributions, we show that spurious singularities, proportional to EoM, can be misinterpreted as genuine divergences in quantum chromodynamics factorization unless properly identified and removed.

United States

Swagato Mukherjee

Vladimir V. Skokov

Andrey Tarasov

Shaswat Tiwari

Perturbative corrections to quark TMDPDFs in the background-field method: Gauge invariance, equations of motion, and multiple interactions

Recently, a new approach for high loop integrals has been proposed in [1], where the whole parameter integration has been divided into two parts: a one-loop-like integration and the remaining parameter integration. In this paper, we systematically study the one-loop-like integrals. We establish the IBP relations for the integral family and show how to complete the reduction. We find the canonical master integrals and write down the corresponding canonical differential equations.

Jiaqi Chen

Bo Feng

Liang Zhang

The canonical differential equations of the one-loop-like integrals

Using PREM as a reference model for the Earth density distribution we investigate the sensitivity of the Hyper-Kamiokande (HK) detector to deviations of the Earth (i) core average density $$\bar{\rho }_C$$ , (ii) lower mantle average density $$\bar{\rho }_{lman}$$ ) and (iii) upper mantle average density $$\bar{\rho }_{uman}$$ , from their respective PREM densities. The analysis is performed by studying the effects of the Earth matter on the oscillations of atmospheric $$\nu _{\mu }$$ , $$\nu _e$$ , $$\bar{\nu }_\mu $$ and $$\bar{\nu }_e$$ . We implement the constraints on the variations of $$\rho _C$$ , $$\rho _{lman}$$ and $$\rho _{uman}$$ following from the precise knowledge of the Earth mass $$M_\oplus $$ and moment of inertia $$I_\oplus $$ , as well as from the requirement that the Earth be in hydrostatic equilibrium (EHE). These constraints limit in the case of the three layer Earth density structure we are considering the maximal positive deviation of $$\bar{\rho }_C$$ from its PREM value to $$10\%$$ . Considering the case of normal ordering (NO) of neutrino masses, we present results which illustrate the dependence of sensitivity to the core, lower and upper mantle average densities on the energy and zenith angle resolutions and on the value of $$\theta _{23}$$ . We show, in particular, that in the “nominal” case of neutrino energy resolution $$E_{res} = 30\%$$ and zenith angle resolution $$\theta _{zres} = 20^\circ $$ and for, e.g., $$\sin ^2\theta _{23}=0.45~(0.58)$$ , HK can determine the average core density $$\bar{\rho }_C$$ at $$2\sigma $$ C.L. after 6500 days of operation with an uncertainty of ( $$-$$ 14.5%)/+39.5% (( $$-$$ 9.3%/+31.7%). In the ”more favorable” case of $$E_{res}= 20\%$$ and $$\theta _{zres} = 10^\circ $$ , and if $$\sin ^2\theta _{23}=0.58~(0.45)$$ , the core density would be determined at $$2\sigma $$ C.L. with an uncertainty of ( $$-$$ 8.3%)/+9.8% (( $$-$$ 9.2%)/+11.3%).

Japan

C. Jesús-Valls

Bulgaria

Italy

S. Petcov

J. Xia

Neutrino oscillation tomography of the Earth with the Hyper-Kamiokande detector

Improved Kogut-Susskind Hamiltonians for quantum simulations of non-Abelian Yang-Mills gauge theories are developed for honeycomb (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>2</mn><mo>+</mo><mn>1</mn><mi mathvariant="normal">D</mi></mrow></math>) and hyperhoneycomb (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>3</mn><mo>+</mo><mn>1</mn><mi mathvariant="normal">D</mi></mrow></math>) spatial tessellations. This is motivated by the desire to identify lattices for quantum simulations that involve only 3-link vertices among the gauge field group spaces in order to reduce the complexity in applications of the plaquette operator. For the honeycomb lattice, we derive a classically <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><msup><mi>b</mi><mn>2</mn></msup><mo stretchy="false">)</mo></math>-improved Hamiltonian, with <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>b</mi></math> being the lattice spacing. Tadpole improvement via the mean-field value of the plaquette operator is used to provide the corresponding quantum improvements. We have identified the (nonchiral) hyperhoneycomb as a candidate spatial tessellation for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>3</mn><mo>+</mo><mn>1</mn><mi mathvariant="normal">D</mi></mrow></math> quantum simulations of gauge theories, and determined the associated <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><mi>b</mi><mo stretchy="false">)</mo></math>-improved Hamiltonian.

Marc Illa

Martin J. Savage

Xiaojun Yao

Improved honeycomb and hyperhoneycomb lattice Hamiltonians for quantum simulations of non-Abelian gauge theories

The valence quark parton distribution functions (PDFs) of all ground state heavy mesons composed of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>b</mi></math> or <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>c</mi></math> quarks, are discussed; namely, the pseudoscalar <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>η</mi><mi>c</mi></msub><mo stretchy="false">(</mo><mn>1</mn><mi>S</mi><mo stretchy="false">)</mo></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>η</mi><mi>b</mi></msub><mo stretchy="false">(</mo><mn>1</mn><mi>S</mi><mo stretchy="false">)</mo></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>B</mi><mi>c</mi></msub></math>, together with the corresponding vector ones, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>J</mi><mo>/</mo><mi>ψ</mi></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="normal">ϒ</mi><mo stretchy="false">(</mo><mn>1</mn><mi>S</mi><mo stretchy="false">)</mo></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>B</mi><mi>c</mi><mo>*</mo></msubsup></math>. We use a quantum chromodynamics (QCD)-inspired constituent quark model, which has been applied with success to conventional heavy mesons, so that one advantage here is that all parameters have already been fixed by previous studies. The wave functions of the heavy mesons in the rest frame are obtained by solving the Schrödinger equation, then boosted to its light-front, based on Susskind’s Lorentz transformation. The PDFs at the hadron scale, are then obtained by integrating out the transverse momenta of the modulus square of the light-front wave function. Our study shows how the valence quark distributions differ between pseudoscalar and vector mesons, as well as among charmonia, bottomonia and bottom-charmed mesons. Comparisons with other theoretical calculations demonstrate that the PDFs obtained herein are in general narrower but align well with the expected patterns. Moreover, each PDF’s pointwise behavior is squeezed with respect to the scale-free partonlike PDF.

Qian Wu

Zhu-Fang Cui

Spain

Jorge Segovia

Parton distribution functions of ground state mesons composed of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>c</mi></math> or <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>b</mi></math> quarks

In spacetime dimensions of 4 (i.e., 3+1) and higher, topological orders exhibit spatially extended excitations like loops and membranes, which support diverse topological data characterizing braiding, fusion, and shrinking processes, despite the absence of anyons. Our understanding of these topological data remains less mature compared to 3D, where anyons have been extensively studied and can be fully described through diagrammatic representations. Inspired by recent advancements in field theory descriptions of higher-dimensional topological orders, this paper systematically constructs diagrammatic representations for 4D and 5D topological orders described by $\textit{BF}$ theory, generalizable to higher dimensions. We introduce elementary diagrams for fusion and shrinking processes, treating them as vectors in fusion and shrinking spaces, respectively, and build complex diagrams by combining these elementary diagrams. Within these vector spaces, we design unitary operations represented by $\textit{F}$-, ∆-, and ∆ -symbols to transform between different bases. We discover $\textit{pentagon equations}$ and $\textit{(hierarchical) shrinking-fusion hexagon equations}$ that impose constraints on the legitimate forms of these unitary operations. We conjecture that the diagrammatic representations we construct apply to all anomaly-free higher-dimensional topological orders, which must satisfy these conditions and any violations indicate a quantum anomaly. This work opens promising avenues for future research, including the exploration of diagrammatic representations involving braiding and the study of non-invertible symmetries and symmetry topological field theories in higher spacetime dimensions.

Yizhou Huang

Germany

Zhi-Feng Zhang

Peng Ye

Diagrammatics, pentagon equations, and hexagon equations of topological orders with loop- and membrane-like excitations

We analyze the effect of a variation of the strange nucleon matrix element $$ \left\langle N|{m}_s\overline{s}s|N\right\rangle $$ on the abundances of the light elements produced in the Big Bang. For that, we vary the nucleon mass in the leading eight reactions that involve neutrons, protons and the four lightest nuclei. We use various available Big Bang nucleosynthesis codes and find that the measured deuterium and He abundances set strict limits on the nucleon mass variations. This translates into an upper bound of possible variations of the strange quark mass, |∆$\textit{m}$ /$\textit{m}$ | ≤ 5.1%.

Ulf-G. Meißner

Bernard Metsch

Helen Meyer

Bounds on variations of the strange quark mass from Big Bang nucleosynthesis