This Letter presents the first search for dark matter axions with mass in the ranges <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>76.56</mn></mrow></math> to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>76.82</mn><mtext> </mtext><mtext> </mtext><mrow><mi mathvariant="normal">μ</mi><mi>eV</mi></mrow></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>79.31</mn></mrow></math> to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>79.53</mn><mtext> </mtext><mtext> </mtext><mrow><mi mathvariant="normal">μ</mi><mi>eV</mi></mrow></math> using a prototype setup for the MAgnetized Disk and Mirror Axion eXperiment (MADMAX). The experimental setup employs a dielectric haloscope consisting of three sapphire disks and a mirror to resonantly enhance the axion-induced microwave signal within the magnetic dipole field provided by the 1.6 T Morpurgo magnet at CERN. Over 14.5 days of data collection, no axion signal was detected. A 95% CL upper limit on the axion-photon coupling strength down to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mo stretchy="false">|</mo><msub><mrow><mi>g</mi></mrow><mrow><mi>a</mi><mi>γ</mi></mrow></msub><mo stretchy="false">|</mo><mo>∼</mo><mn>2</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>11</mn></mrow></msup><mtext> </mtext><mtext> </mtext><msup><mrow><mi>GeV</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math> is set in the targeted mass ranges, surpassing previous constraints, assuming a local axion dark matter density <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>ρ</mi><mi>a</mi></msub></math> of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>0.3</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi><mo>/</mo><msup><mrow><mi>cm</mi></mrow><mrow><mn>3</mn></mrow></msup></mrow></math>. This study marks the first axion dark matter search using a dielectric haloscope.

Germany

B. Ary dos Santos Garcia

D. Bergermann

A. Caldwell

France

V. Dabhi

C. Diaconu

J. Diehl

G. Dvali

J. Egge

E. Garutti

S. Heyminck

F. Hubaut

A. Ivanov

J. Jochum

United States

S. Knirck

M. Kramer

D. Kreikemeyer-Lorenzo

C. Krieger

C. Lee

D. Leppla-Weber

X. Li

A. Lindner

B. Majorovits

J.P.A. Maldonado

A. Martini

A. Miyazaki

E. Öz

P. Pralavorio

G. Raffelt

Spain

J. Redondo

A. Ringwald

J. Schaffran

A. Schmidt

F. Steffen

C. Strandhagen

I. Usherov

H. Wang

G. Wieching

First Search for Axion Dark Matter with a MADMAX Prototype

The photon sphere defines the unstable circular orbit of photons in a black hole spacetime. Photons emitted by a source located inside the photon sphere can be gravitationally lensed by the black hole and have time delays when reaching the observer. These delays may lead to light echoes produced in the light curve if an accretion event in the vicinity of the horizon can be observed. In this work, we present fully analytical formulas with high accuracy to describe the change of the azimuthal angle and the travel time of those photons. By employing the analytical approaches, we find that the time delay between photons emitted from the interior of the photon sphere has a typical time scale of $$2(\pi - \phi _\textrm{S}) u_\textrm{m}$$ with $$\phi _\textrm{S}$$ and $$u_\textrm{m}$$ being respectively the azimuthal angle of the source and the impact parameter evaluated at the photon sphere, which can provide some clues on the future search for gravitational lensing signatures in the accretion inflow event.

China

Yuan-Xing Gao

Analytical description for light propagation with the source inside the black hole photon sphere

We investigate the volume and lifetime of the high-baryon-density matter created in heavy-ion collisions and estimate the optimal collision-energy range to realize the high-baryon-density region over a large space-time volume. We simulate central collisions of gold ions for the center-of-mass energy per nucleon pair <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msqrt><msub><mi>s</mi><mrow><mi>N</mi><mi>N</mi></mrow></msub></msqrt><mo>=</mo><mn>2.4</mn><mo>−</mo><mn>19.6</mn><mspace width="0.28em"></mspace><mi>GeV</mi></mrow></math> with a microscopic transport model JAM. We discover that the optimal range is around <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msqrt><msub><mi>s</mi><mrow><mi>N</mi><mi>N</mi></mrow></msub></msqrt><mo>=</mo><mn>3</mn><mo>−</mo><mn>5</mn><mspace width="0.28em"></mspace><mi>GeV</mi></mrow></math>, where a baryon density exceeding three times the normal nuclear density is realized with a substantially large space-time volume. Higher and lower energies are disfavored due to short lifetime and low density, respectively. We also point out that event-by-event fluctuations of the space-time density profile are large, indicating the importance of the event selection in the experimental analysis.

Japan

Hidetoshi Taya

Asanosuke Jinno

Masakiyo Kitazawa

Yasushi Nara

Optimal collision-energy range for realizing macroscopic high-baryon-density matter

We revisit birefringence effects associated with the evolution of the polarization of light as it propagates through axion dark matter or the background of a passing gravitational wave (GW). We demonstrate that this can be described by a unified formalism, highlighting a synergy between searches for axions and high-frequency GWs. We show that by exploiting this framework, the optical cavities used by the ALPS II experiment can potentially probe axion masses in the range <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><mi>a</mi></msub><mo>∼</mo><mrow><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>9</mn></mrow></msup><mi>–</mi><mrow><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>6</mn></mrow></msup><mtext> </mtext><mtext> </mtext><mi>eV</mi></mrow></mrow></math>, offering competitive sensitivity with existing laboratory and astrophysical searches. Also building on this approach, we propose using these optical cavities to search for high-frequency GWs by measuring changes in the polarization of their circulating laser fields. This makes it a promising method for exploring, in the near future, GWs with frequencies above 100 MHz and strain sensitivities on the order of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>14</mn></mrow></msup><mtext> </mtext><mtext> </mtext><msup><mrow><mi>Hz</mi></mrow><mrow><mo>−</mo><mn>1</mn><mo>/</mo><mn>2</mn></mrow></msup></mrow></math>. Such sensitivity allows the exploration of currently unconstrained parameter space, complementing other high-frequency GW experiments. This work contributes to the growing community investigating novel approaches for high-frequency GW detection.

Camilo García-Cely

Luca Marsili

Andreas Ringwald

Aaron D. Spector

Polarimetric searches for axion dark matter and high-frequency gravitational waves using optical cavities

Atmospheric neutrino oscillations are important to the study of neutrino properties, including the neutrino mass ordering problem. A good capability to identify neutrinos’ flavor and neutrinos against antineutrinos is crucial in such measurements. In this paper, we present a machine-learning-based approach for identifying atmospheric neutrino events in a large homogeneous liquid scintillator detector. This method identifies features of photomultiplier tube waveforms that reflect event topologies and uses them as input to machine learning models. In addition, neutron-capture information is utilized to achieve neutrino vs antineutrino discrimination. Preliminary performances based on Monte Carlo simulations are presented, which demonstrate such a detector’s potential in future measurements of atmospheric neutrinos such as the one planned for the JUNO experiment.

Jiaxi Liu

Fanrui Zeng

Hongyue Duyang

Wanlei Guo

Xinhai He

Teng Li

Zhen Liu

Wuming Luo

Wing Yan Ma

Xiaohan Tan

Liangjian Wen

Zekun Yang

Yongpeng Zhang

Neutrino type identification for atmospheric neutrinos in a large homogeneous liquid scintillation detector

We investigate the production of charged scalar boson pairs <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>H</mi><mo>−</mo></msup><msup><mi>H</mi><mo>+</mo></msup></math> via photon-photon fusion in proton-proton collisions at the High-Luminosity LHC (HL-LHC), High-Energy LHC (HE-LHC), and Future Circular hadron-hadron Collider (FCC-hh). The analysis is performed within the framework of the Two-Higgs-Doublet Model type-III, which predicts large branching ratios for the decay channel <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>H</mi><mo>±</mo></msup><mo stretchy="false">→</mo><msup><mi>τ</mi><mo>±</mo></msup><msub><mi>ν</mi><mi>τ</mi></msub></math>, the focus of this work. Motivated by the current excess of events in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi mathvariant="script">B</mi><mi mathvariant="script">R</mi></mrow><mo stretchy="false">(</mo><mi>t</mi><mo stretchy="false">→</mo><msup><mi>H</mi><mo>±</mo></msup><mi>b</mi><mo stretchy="false">)</mo><mo>×</mo><mrow><mi mathvariant="script">B</mi><mi mathvariant="script">R</mi></mrow><mo stretchy="false">(</mo><msup><mi>H</mi><mo>±</mo></msup><mo stretchy="false">→</mo><mi>c</mi><mi>b</mi><mo stretchy="false">)</mo></math> for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>M</mi><msup><mi>H</mi><mo>±</mo></msup></msub><mo>=</mo><mn>130</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math>, we explore charged Higgs boson masses in the range <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>M</mi><msup><mi>H</mi><mo>±</mo></msup></msub><mo>=</mo><mn>100</mn><mi>–</mi><mn>150</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math>. Using benchmark points (BPs) consistent with current experimental constraints, we evaluate the process <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>γ</mi><mi>γ</mi><mo stretchy="false">→</mo><msup><mi>H</mi><mo>−</mo></msup><msup><mi>H</mi><mo>+</mo></msup><mo stretchy="false">→</mo><mi>τ</mi><msub><mi>ν</mi><mi>τ</mi></msub><mi>τ</mi><msub><mi>ν</mi><mi>τ</mi></msub><mo stretchy="false">→</mo><mi>e</mi><mi>μ</mi><mo>+</mo><msub><menclose notation="updiagonalstrike"><mi>E</mi></menclose><mi>T</mi></msub></math> and find signal significances <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo>≳</mo><mn>5</mn><mi>σ</mi></math> across the entire mass range. For the most favored BP with <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>M</mi><msup><mi>H</mi><mo>±</mo></msup></msub><mo>=</mo><mn>130</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math>, we predict significances of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>3</mn><mi>σ</mi></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>5</mn><mi>σ</mi></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>8</mn><mi>σ</mi></math> with integrated luminosities of 3000, 2300, and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>300</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math> at center-of-mass energies of 14 TeV (HL-LHC), 27 TeV (HE-LHC), and 100 TeV (FCC-hh), respectively.

Mexico

M.A. Arroyo-Ureña

O. Félix-Beltrán

J. Hernández-Sánchez

C.G. Honorato

T.A. Valencia-Pérez

Prospects for observing novel photon-induced <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mi>H</mi></mrow><mrow><mo>−</mo></mrow></msup><msup><mrow><mi>H</mi></mrow><mrow><mo>+</mo></mrow></msup></mrow></math> production at the high luminosity LHC

Coulomb branches of vacua are the most universal moduli spaces that arise in local unitary interacting 4d $$ \mathcal{N} $$ = 2 superconformal field theories (SCFTs). In these theories, 1/2-BPS primaries parameterize the Coulomb branches and form (anti-)chiral rings. We define the notion of a Coulomb branch operator algebra, $$ {\mathcal{A}}_{\mathcal{C}} $$ , that contains these chiral and anti-chiral rings along with infinitely many more operators and products that are less protected by supersymmetry. Using a universal symmetry, $$ \mathcal{I}\cong {\mathbb{Z}}_2 $$ , that arises from studying the superconformal group, we give $$ \mathcal{I} $$ selection rules for $$ {\mathcal{A}}_{\mathcal{C}} $$ and, more generally, for arbitrary products in the local operator algebra of any 4d $$ \mathcal{N} $$ = 2 SCFT. Defining the notion of a “Coulombic” SCFT, we propose explanations for certain phenomena in a 4d/2d correspondence involving 4d $$ \mathcal{N} $$ = 2 theories and 2d vertex operator algebras. Finally, by considering deformations of $$ \mathcal{I} $$ , we explore the case of $$ \mathcal{N} $$ > 2 SCFTs.

United Kingdom

Matthew Buican

Coulomb branch operator algebras and universal selection rules for $$ \mathcal{N} $$ = 2 SCFTs

Jets with different radius parameters $\textit{R}$ are an important tool for probing quantum chromodynamics processes at different angular scales. Jets with small $$R=0.2$$ are instrumental in measurements of the substructure of large-$\textit{R}$ jets resulting from collimated hadronic decays of energetic $\textit{W}$, $\textit{Z}$, and Higgs bosons, top quarks, and of potential new resonances. This paper presents measurements of the energy scale, resolution, and associated uncertainties of jets with radius parameters $$R=0.2$$ and 0.6, obtained using the ATLAS detector. The results are based on $$37~\text {fb}^{-1}$$ of proton–proton collision data from the Large Hadron Collider at a centre-of-mass energy of $$\sqrt{s}=13$$ TeV. A new $\textit{in situ}$ method for measuring jet energy scale differences between data and Monte Carlo simulations is presented. The systematic uncertainties in the jet energy scale for central jets $$(|\eta | < 1.2)$$ typically vary from 1% to about 5% as a function of $$|\eta |$$ at very low transverse momentum, $$p_{\text {T}},$$ of around 20 GeV for both $$R=0.2$$ and 0.6 jets. The relative energy resolution ranges from $$(35 \pm 6)\%$$ at $$p_{\text {T}} = 20$$ GeV to $$(6 \pm 0.5)\%$$ at $$p_{\text {T}} = 300$$ GeV for central $$R=0.2$$ jets, and is found to be slightly worse for $$R=0.6$$ jets. Finally, the effect of close-by hadronic activity on the jet energy scale is investigated and is found to be well modelled by the ATLAS Monte Carlo simulations.

G. Aad

Norway

E. Aakvaag

B. Abbott

United Arab Emirates

S. Abdelhameed

K. Abeling

N. Abicht

S. Abidi

M. Aboelela

Morocco

A. Aboulhorma

Israel

H. Abramowicz

Y. Abulaiti

Italy

B. Acharya

A. Ackermann

C. Adam Bourdarios

Poland

L. Adamczyk

S. Addepalli

M. Addison

J. Adelman

Türkiye

A. Adiguzel

T. Adye

A. Affolder

Y. Afik

M. Agaras

A. Aggarwal

Romania

C. Agheorghiesei

Azerbaijan

F. Ahmadov

S. Ahuja

X. Ai

G. Aielli

A. Aikot

M. Ait Tamlihat

B. Aitbenchikh

M. Akbiyik

Sweden

T. Åkesson

A. Akimov

D. Akiyama

N. Akolkar

S. Aktas

G. Alberghi

Canada

J. Albert

P. Albicocco

G. Albouy

S. Alderweireldt

Z. Alegria

Switzerland

M. Aleksa

I. Aleksandrov

C. Alexa

Greece

T. Alexopoulos

F. Alfonsi

M. Algren

M. Alhroob

Czechia

B. Ali

Saudi Arabia

H. Ali

S. Ali

S. Alibocus

South Africa

M. Aliev

G. Alimonti

W. Alkakhi

C. Allaire

B. Allbrooke

J. Allen

P. Allport

A. Aloisio

Argentina

F. Alonso

C. Alpigiani

Z. Alsolami

A. Alvarez Fernandez

M. Alves Cardoso

M. Alviggi

M. Aly

Brazil

Y. Amaral Coutinho

A. Ambler

C. Amelung

M. Amerl

C. Ames

D. Amidei

B. Amini

K. Amirie

A. Amirkhanov

Portugal

S. Amor Dos Santos

K. Amos

D. Amperiadou

S. An

V. Ananiev

C. Anastopoulos

T. Andeen

J. Anders

A. Anderson

A. Andreazza

S. Angelidakis

A. Angerami

A. Anisenkov

A. Annovi

C. Antel

Energy scale and resolution for anti- $$k_t$$ jets with radius parameters $$R=0.2$$ and 0.6 measured in proton-proton collisions at $$\sqrt{s} = 13$$ TeV with the ATLAS detector