We consider planar $$ \mathcal{N} $$ = 4 super Yang-Mills at finite temperature with chemical potentials that couple either to the $\textit{R}$-charges or the spins of the operators. We find expressions for the Hagedorn temperatures at both zero coupling by explicitly counting states, and at strong coupling using the string theory dual. We then apply the quantum spectral curve (QSC) to this problem, which adds additional twists to the $\textit{Q}$-functions. For a single chemical potential $\textit{μ}$ coupled to one of the $\textit{R}$-charges, we find the analytic weak-coupling Hagedorn temperature to one-loop order for any value of $\textit{μ}$, and to two-loop order for $\textit{μ}$ = 1/2. We then solve the QSC numerically, showing that at strong coupling there is good agreement with the string theory prediction to order 1/$\textit{λ}$ . This provides further evidence for a recent conjecture of Harmark for the form of the world-sheet zero-point shift. We also use the QSC to find the analytic one-loop correction to the Hagedorn temperature with non-zero chemical potentials coupled to the spins.

Sweden

United Kingdom

Simon Ekhammar

United States

Joseph Minahan

Charles Thull

Twisting the Hagedorn temperature in planar $$ \mathcal{N} $$ = 4 super Yang-Mills

Right-handed neutrinos are naturally induced by dark extra dimension models and play an essential role in neutrino oscillations. The model parameters can be examined by the long-baseline neutrino oscillation experiments. In this work, we compute the predicted neutrino oscillation spectra within/without extra dimension models and compare them with the experimental data. We find that the neutrino data in the T2K and NOvA experiments are compatible with the standard neutrino oscillation hypothesis. The results set the stringent exclusion limit on the extra dimension model parameters at a high confidence level. The derived constraints on dark dimension right-handed neutrinos are complementary to those results from the collider experiments and cosmological observations.

China

Ai-Yu Bai

Thailand

Auttakit Chatrabhuti

Yin-Yuan Huang

Hiroshi Isono

Jian Tang

Dark dimension right-handed neutrinos confronted with long-baseline oscillation experiments

We determine the parametric conditions (pulse strength and duration) under which Schwinger’s prediction for the pair-creation current—and therefore the probability—is significantly altered.

Russia

E.T. Akhmedov

P.S. Zavgorodny

Does Schwinger’s value for the current of created pairs get modified for a long and strong enough pulse?

We investigate the high-energy, small-angle limit of two-body gravitational scattering. Using power counting arguments and dispersion relations in an effective field theory for the Regge regime, we derive the general loop expansion that determines how the leading Regge logarithms and their complex structure arise as a power series in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>t</mi><mo>/</mo><mi>s</mi></math>. Focusing on the tower of multi-H diagrams that govern the leading logarithmic behavior, we compute the leading double logarithm at four loops (or equivalently fifth post-Minkowskian order, 5PM) using both effective field theory methods and the multi-Regge expansion, finding complete agreement. Finally, using the aforementioned dispersion relations, we extract the single logarithmic contribution to the imaginary part of the eikonal phase at 5PM in the Regge limit.

Italy

Francesco Alessio

Vittorio Del Duca

Riccardo Gonzo

Emanuele Rosi

Ira Z. Rothstein

Michael Saavedra

Analytic structure of the high-energy gravitational amplitude: Multi-<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>H</mi></math> diagrams and classical 5PM logarithms

We present model calculations for the in-medium suppression of the Υ(1 <italic>S</italic>, 2 <italic>S</italic>, 3 <italic>S</italic>) states in <math altimg='si1.svg'><mrow><msqrt><msub><mi>s</mi><mrow><mi>N</mi><mi>N</mi></mrow></msub></msqrt><mo linebreak='goodbreak'>=</mo><mn>5.02</mn></mrow></math> TeV Pb-Pb collisions at the Large Hadron Collider in comparison with recent CMS data for all three spin-triplet <italic>s</italic>-wave states. The model parameters initial central temperature, and formation times for the &#933;( <italic>nS</italic>) states are determined in simultaneous <italic>&#967;</italic> 2 minimizations with respect to the data, such that the sequential centrality- and transverse-momentum-dependent suppression of the observed states is reproduced.

Germany

J. Majonica

G. Wolschin

In-medium Υ(1 <italic>S</italic>, 2 <italic>S</italic>, 3 <italic>S</italic>) suppression in Pb-Pb collisions at <math altimg='si1.svg'><mrow><msqrt><msub><mi>s</mi><mrow><mi>N</mi><mi>N</mi></mrow></msub></msqrt><mo linebreak='goodbreak'>=</mo><mn>5.02</mn></mrow></math> TeV

Generalised spin structures are necessary for placing fermions on manifolds that do not admit a standard spin structure. This is especially relevant in a dimensional reduction on such a manifold, which can then be compensated by using fermions that are appropriately charged under some Maxwell or Yang-Mills field defined on the internal manifold. A well known example in the physics literature is $$ {\mathbbm{CP}}^2 $$ , which has four real dimensions and is the coset SU(3)/U(2). In this paper we focus on a five-dimensional coset space, namely the Wu manifold SU(3)/SO(3) , where SO(3) is maximal in SU(3). Intriguingly, the Wu manifold does not admit a spin structure or spin structure, it does admit a spin structure. We provide a physical interpretation of the spin structure by considering spinors that are coupled to an SO(3) Yang-Mills field defined on the Wu manifold, but which carry half-integer “isospin,” thereby canceling the minus sign in the holonomy for uncharged spinors that provides the original obstruction to an ordinary spin structure. We also construct a gauge-covariantly constant spinor in the Wu manifold, and we show how this can be employed in order to construct spin spinor harmonics from scalar harmonics. We provide a very explicit construction of all the scalar and spin harmonics. In a follow-up paper, we shall employ the results we obtain here in order to discuss dimensional reductions and consistent reductions on the Wu manifold.

Cameron Gibson

Okan Günel

Gabriel Larios

C. Pope

Spin $\textit{h}$ structure, scalar and charged spinor eigenfunctions on the SU(3)/SO(3) Wu manifold

We compute the contour integral for the partition function of an $$ \mathcal{N} $$ = 2 SU(2) topologically twisted theory on $$ {\mathbbm{CP}}^2 $$ , dimensionally reducing from an $$ \mathcal{N} $$ = 1 theory on $\textit{S}$ . Earlier works presented the partition function as a sum over three equivariant fluxes, one for each toric divisor of $$ {\mathbbm{CP}}^2 $$ . Our result depends only on a single physical flux, assigned to the non-trivial two-cycle of the manifold. The reduced summation over fluxes is compensated by a contour of integration, arising from a different solution of the BPS equations, which captures more poles in each topological sector. As our observable involves a position-dependent Yang-Mills coupling, we compute new equivariant invariants of $$ {\mathbbm{CP}}^2 $$ , which reduce to Donaldson invariants in the non-equivariant limit. Stability conditions of gauge bundles over $$ {\mathbbm{CP}}^2 $$ appear intrinsically via the dimensional reduction.

Lorenzo Ruggeri

Contour integral for the partition function of $$ \mathcal{N} $$ = 2 topologically twisted on $$ {\mathbbm{CP}}^2 $$ and physical fluxes

The effective number of neutrino species, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>N</mi><mi>eff</mi></msub></math>, serves as a key fitting parameter extensively employed in cosmological studies. In this work, we point out a fundamental inconsistency in the conventional treatment of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>N</mi><mi>eff</mi></msub></math> in big bang nucleosynthesis (BBN), particularly regarding its applicability to new physics scenarios where <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="normal">Δ</mi><msub><mi>N</mi><mi>eff</mi></msub></math>, the deviation of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>N</mi><mi>eff</mi></msub></math> from the standard BBN prediction, is negative. To ensure consistent interpretation, it is imperative to either restrict the allowed range of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>N</mi><mi>eff</mi></msub></math> or systematically adjust neutrino-induced reaction rates based on physically motivated assumptions. As a concrete example, we consider a simple scenario in which a negative <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="normal">Δ</mi><msub><mi>N</mi><mi>eff</mi></msub></math> arises from entropy injection into the electromagnetic sector due to the decay of long-lived particles after neutrino decoupling. This process dilutes the neutrino density and suppresses the rate of neutrino-driven neutron-proton conversion. Under this assumption, we demonstrate that the resulting BBN constraints on <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>N</mi><mi>eff</mi></msub></math> deviate significantly from those obtained by the conventional, but unphysical, extrapolation of dark radiation scenarios into the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="normal">Δ</mi><msub><mi>N</mi><mi>eff</mi></msub><mo>&lt;</mo><mn>0</mn></math> regime.

South Korea

Sougata Ganguly

Tae Hyun Jung

Seokhoon Yun

Consistent <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>N</mi><mi>eff</mi></msub></math> fitting in big bang nucleosynthesis analysis

We search for 15 rare decays of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>D</mi></math> mesons to hadrons accompanied by an electron-positron pair <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>D</mi><mo stretchy="false">→</mo><mi>h</mi><mo stretchy="false">(</mo><msup><mrow><mi>h</mi></mrow><mrow><mrow><mo stretchy="false">(</mo><mo>′</mo><mo stretchy="false">)</mo></mrow></mrow></msup><mo stretchy="false">)</mo><msup><mrow><mi>e</mi></mrow><mrow><mo>+</mo></mrow></msup><msup><mrow><mi>e</mi></mrow><mrow><mo>−</mo></mrow></msup></mrow></math>, based on <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>20.3</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math> of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math> collision data collected at the center-of-mass energy of 3.773 GeV with the BESIII detector at BEPCII. No significant signals are observed, and the corresponding upper limits on the branching fractions at the 90% confidence level are determined. The sensitivities of the results are at the level of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mn>10</mn><mrow><mo>−</mo><mn>6</mn></mrow></msup><mo>∼</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>7</mn></mrow></msup></math>. The upper limits on the branching fractions for the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mo>+</mo></msup><mo stretchy="false">→</mo><msup><mi>ρ</mi><mo>+</mo></msup><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mo>+</mo></msup><mo stretchy="false">→</mo><msup><mi>K</mi><mrow><mo>*</mo><mo>+</mo></mrow></msup><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mn>0</mn></msup><mo stretchy="false">→</mo><msubsup><mi>K</mi><mi>S</mi><mn>0</mn></msubsup><msubsup><mi>K</mi><mi>S</mi><mn>0</mn></msubsup><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mn>0</mn></msup><mo stretchy="false">→</mo><msup><mi>π</mi><mn>0</mn></msup><msup><mi>π</mi><mn>0</mn></msup><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mn>0</mn></msup><mo stretchy="false">→</mo><msup><mi>η</mi><mo>′</mo></msup><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math> decay channels are measured for the first time. For the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mn>0</mn></msup><mo stretchy="false">→</mo><msup><mi>π</mi><mn>0</mn></msup><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mn>0</mn></msup><mo stretchy="false">→</mo><mi>η</mi><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mn>0</mn></msup><mo stretchy="false">→</mo><mi>ω</mi><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mn>0</mn></msup><mo stretchy="false">→</mo><msubsup><mi>K</mi><mi>S</mi><mn>0</mn></msubsup><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mo>+</mo></msup><mo stretchy="false">→</mo><msup><mi>π</mi><mo>+</mo></msup><msup><mi>π</mi><mn>0</mn></msup><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mo>+</mo></msup><mo stretchy="false">→</mo><msup><mi>K</mi><mo>+</mo></msup><msup><mi>π</mi><mn>0</mn></msup><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mo>+</mo></msup><mo stretchy="false">→</mo><msup><mi>π</mi><mo>+</mo></msup><msubsup><mi>K</mi><mi>S</mi><mn>0</mn></msubsup><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mo>+</mo></msup><mo stretchy="false">→</mo><msup><mi>K</mi><mo>+</mo></msup><msubsup><mi>K</mi><mi>S</mi><mn>0</mn></msubsup><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math> decay channels, the upper limits on the branching fractions are determined, with an improvement of at least a factor of four compared to previous searches. The upper limits on the branching fractions for the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mn>0</mn></msup><mo stretchy="false">→</mo><msup><mi>ρ</mi><mn>0</mn></msup><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mn>0</mn></msup><mo stretchy="false">→</mo><mi>ϕ</mi><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math> decay channels are set at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>0.7</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>6</mn></mrow></msup></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>4.6</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>6</mn></mrow></msup></math>, respectively.

M. Ablikim

M.N. Achasov

P. Adlarson

X.C. Ai

C.S. Akondi

R. Aliberti

A. Amoroso

Q. An

Y.H. An

Y. Bai

JINR

O. Bakina

H.R. Bao

X.L. Bao

M. Barbagiovanni

Poland

V. Batozskaya

Mongolia

K. Begzsuren

N. Berger

M. Berlowski

M.B. Bertani

D. Bettoni

F. Bianchi

E. Bianco

A. Bortone

I. Boyko

R.A. Briere

A. Brueggemann

D. Cabiati

H. Cai

M.H. Cai

X. Cai

A. Calcaterra

G.F. Cao

N. Cao

Türkiye

S.A. Cetin

X.Y. Chai

J.F. Chang

T.T. Chang

G.R. Che

Y.Z. Che

C.H. Chen

Chao Chen

G. Chen

H.S. Chen

H.Y. Chen

M.L. Chen

S.J. Chen

S.M. Chen

T. Chen

W. Chen

X.R. Chen

X.T. Chen

X.Y. Chen

Y.B. Chen

Y.Q. Chen

Z.K. Chen

J. Cheng

L.N. Cheng

S.K. Choi

X. Chu

G. Cibinetto

F. Cossio

J. Cottee-Meldrum

H.L. Dai

J.P. Dai

X.C. Dai

A. Dbeyssi

R.E. de Boer

D. Dedovich

C.Q. Deng

Z.Y. Deng

A. Denig

I. Denisenko

M. Destefanis

F. De Mori

E. Di Fiore

X.X. Ding

Y. Ding

Y.X. Ding

Yi. Ding

J. Dong

L.Y. Dong

M.Y. Dong

X. Dong

Z.J. Dong

M.C. Du

S.X. Du

Shaoxu Du

X.L. Du

Y.Q. Du

Y.Y. Duan

Z.H. Duan

P. Egorov

G.F. Fan

J.J. Fan

Y.H. Fan

J. Fang

Jin Fang

S.S. Fang

W.X. Fang

Y.Q. Fang

Search for the rare decays of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>D</mi><mo stretchy="false">→</mo><mi>h</mi><mo stretchy="false">(</mo><msup><mi>h</mi><mrow><mrow><mo stretchy="false">(</mo><mo>′</mo><mo stretchy="false">)</mo></mrow></mrow></msup><mo stretchy="false">)</mo><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math>

We investigate massive scalar perturbations and several characteristics of particle motion in the spacetime of regular black holes arising in four-dimensional quasi-topological gravity. Quasinormal modes are computed using high-order WKB approximations with Padé resummation and verified through time-domain integration. For moderate values of the scalar-field mass, the time-domain profiles confirm the WKB results with excellent accuracy. As the mass increases, the damping rate decreases substantially, indicating the approach to the quasi-resonant regime of long-lived modes. For sufficiently large masses, the late-time signal becomes dominated by oscillatory power-law tails, which mask the quasi-resonant mode in the time-domain profile. In addition, we analyze photon motion and circular geodesics, including the photon-sphere radius, shadow size, Lyapunov exponent, and ISCO characteristics. These quantities exhibit only moderate deviations from their Schwarzschild values, unlike the Hawking temperature of the black hole.

Czechia

Bekir Lütfüoğlu

Long-lived quasinormal modes, shadows and particle motion in four-dimensional quasi-topological gravity