We study the equation of state (EoS) of QCD matter in a bottom-up holographic setup that combines an Einstein-Maxwell-dilaton (EMD) sector with an improved Karch-Katz-Son-Stephanov (KKSS) flavor action. In the probe approximation, we perform an inverse reconstruction of the model functions by parameterizing them with neural networks and solving the EMD equations via a differentiable ODE solver (a neural ODE framework), calibrating the model to a reference thermodynamic table for $(2+1)$ -flavor QCD at finite temperature and finite baryon chemical potential. The reconstructed model functions are then parameterized and kept fixed across thermodynamic states. Next, viewing the EMD sector as an effective description of pure Yang-Mills theory, we fix its parameters by fitting the $\mu_B=0$ lattice pure-glue EoS using a hybrid optimization strategy. Finally, we go beyond the probe limit and solve the coupled EMD+KKSS equations with back-reaction, using the pure-glue-calibrated EMD sector as a fixed input and varying the KKSS couplings to compare with the $\mu_B=0$ two-flavor lattice EoS. We find a visible mismatch and a high-temperature behavior in which the back-reacted dimensionless ratios approach a nearly $\beta_1$ -insensitive plateau close to the pure-glue baseline, providing a simple structural diagnostic for the present flavor-sector truncation.

China

Yutian Deng

Mei Huang

Lin Zhang

Holographic QCD equation of state constrained by lattice QCD: neural-ODE for probe-limit and a back-reaction test * Start-up funding from Sun Yat-sen University (SYSU) (Y. Deng and L. Zhang); National Natural Science Foundation of China (NSFC) (12235016) (L. Zhang and M. Huang) and 12221005 (M. Huang)

We investigate the landscape of 6d 𝒩 = (1$\textit{,}$ 0) D-type orbi-instanton superconformal field theories (SCFTs) and their torus compactifications to four-dimensional class 𝒮 theories. By analysing a general class of 6d F-theory constructions via generalised quivers, we demonstrate that — in contrast to the well-characterised A-type series — the dimensional reductions that admit a 4d class 𝒮 description on a Riemann sphere with three untwisted D-type punctures constitute only a subset of the full orbi-instanton landscape. For this sub-class, we show that the punctures can be effectively characterised by two sets of integers: the $\textit{s}$-labels and the $\textit{m}$-labels. The $\textit{s}$-labels, or “Kac-type labels”, serve as the D-type analogues to the Kac labels used in A-type theories; we establish their correspondence with “modified excess numbers” in the associated 3d mirror theories (magnetic quivers). The $\textit{m}$-labels are further introduced to streamline the mapping from 6d generalised quivers to their class 𝒮 descriptions. Furthermore, we analyse physical distinctions arising from 6d $\textit{θ}$ angles and explore the hierarchy of Higgs branch flows. In doing so, we uncover instances of “hidden Higgsings” — renormalization group flows present in the 6d parent theories that are not manifest in the puncture closures of the corresponding class 𝒮 descriptions.

Japan

Jiakang Bao

Italy

Thailand

Noppadol Mekareeya

Israel

Gabi Zafrir

Hao Zhang

Orbi-instantons and class 𝒮 theories of type D

<p>Dark matter detection experiments using liquid argon rely on a precise characterization of the ionization response to nuclear recoils, especially in the keV energy range relevant for light dark matter interactions. In this work, we present a comprehensive analysis that combines new measurements from the ReD setup, part of the DarkSide experimental program, with calibration data from DarkSide-50, as well as results from the ARIS and SCENE experiments. These combined datasets enable improved constraints on atomic screening effects in the modeling of the ionization response of liquid argon to nuclear recoils. The analysis is performed within the Thomas-Imel recombination framework adopted in previous DarkSide studies, and is here further constrained by the inclusion of ReD data, which allow the screening function to be determined from calibration measurements. By including the updated ionization model into the DarkSide-50 analysis framework, we obtain stronger exclusion limits on low-mass weakly interacting massive particle (WIMP) interactions, setting new world-leading constraints in the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>1</mn><mi>–</mi><mn>3</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi><mo>/</mo><msup><mrow><mi mathvariant="normal">c</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math> WIMP mass range. Finally, we recast the sensitivity projections for the upcoming DarkSide-20k detector, demonstrating a significantly enhanced discovery potential for low-mass dark matter candidates.</p>

F. Acerbi

Canada

P. Adhikari

P. Agnes

Poland

I. Ahmad

S. Albergo

Brazil

I.F. Albuquerque

United States

T. Alexander

A.K. Alton

P. Amaudruz

M. Angiolilli

E. Aprile

M. Atzori Corona

D.J. Auty

M. Ave

Russia

I.C. Avetisov

O. Azzolini

H.O. Back

Germany

Z. Balmforth

Spain

A.I. Barrado Olmedo

France

P. Barrillon

G. Batignani

S. Bharat

United Kingdom

P. Bhowmick

S. Blua

V. Bocci

W. Bonivento

B. Bottino

M.G. Boulay

T. Braun

A. Buchowicz

S. Bussino

J. Busto

M. Cadeddu

R. Calabrese

V. Camillo

A. Caminata

N. Canci

M. Caravati

M. Cárdenas-Montes

N. Cargioli

M. Carlini

P. Cavalcante

S. Cebrian

S. Chashin

A. Chepurnov

S. Choudhary

L. Cifarelli

B. Cleveland

Y. Coadou

I. Coarasa

V. Cocco

E. Conde Vilda

L. Consiglio

A.F.V. Cortez

B.S. Costa

M. Czubak

S. D’Auria

M.D. Da Rocha Rolo

A. Dainty

G. Darbo

S. Davini

R. de Asmundis

S. De Cecco

M. De Napoli

G. Dellacasa

A.V. Derbin

L. Di Noto

P. Di Stefano

L.K. Dias

D. Díaz Mairena

C. Dionisi

G. Dolganov

F. Dordei

V. Dronik

A. Elersich

T. Erjavec

N. Fearon

M. Fernández Díaz

L. Ferro

A. Ficorella

G. Fiorillo

D. Fleming

P. Franchini

D. Franco

H. Frandini Gatti

E. Frolov

F. Gabriele

D. Gahan

C. Galbiati

G. Galiński

G. Gallina

M. Garbini

P. Garcia Abia

A. Gawdzik

G.K. Giovanetti

V. Goicoechea Casanueva

A. Gola

L. Grandi

G. Grauso

G. Grilli di Cortona

Sensitivity to low-mass WIMPs with an improved liquid argon ionization response model within the DarkSide program

<p>Scalar-mediated interactions may exist among neutrinos, dark matter particles, or between the two. Double <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>β</mi></mrow></math>-decay experiments provide a powerful tool to probe such exotic interactions. Using <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><mi>Xe</mi></mrow><mprescripts></mprescripts><none></none><mrow><mn>136</mn></mrow></mmultiscripts></mrow></math> double <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>β</mi></math>-decay data from PandaX-4T, we perform the first direct spectral search in the energy range of 20 to 2800 keV, setting the most stringent limits to date on scalar-mediated neutrino self-interactions for mediator masses below <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>2</mn><mtext> </mtext><mtext> </mtext><mi>MeV</mi><mo>/</mo><msup><mi>c</mi><mn>2</mn></msup></mrow></math>. These results place significant constraints on models invoking such interactions to alleviate the Hubble tension. Assuming the same scalar also mediates dark matter self-interactions, constraints on the dark matter-scalar interactions can be placed in conjunction with cosmological constraints.</p>