A representation of the <math altimg='si1.svg'><mrow><mi mathvariant='fraktur'>so</mi><mo>(</mo><mn>2</mn><mo>,</mo><mn>5</mn><mo>)</mo></mrow></math> algebra corresponding to the continuous spin field in <bold>AdS<inf>6</inf></bold> is considered. The algebra is realized using the Lie-Lorentz derivative, which naturally incorporates <bold>AdS<inf>6</inf></bold> geometry and spin degrees of freedom. Within this framework, we derive explicit expressions for the Casimir operators in terms of both the covariant derivative and spin invariants. The continuous spin representation under consideration is defined by a system of operator constraints that generalize those known for six-dimensional Minkowski space. We demonstrate that these constraints completely fix all Casimir operators of the <math altimg='si1.svg'><mrow><mi mathvariant='fraktur'>so</mi><mo>(</mo><mn>2</mn><mo>,</mo><mn>5</mn><mo>)</mo></mrow></math> algebra with eigenvalues determined by the dimensional real parameter <bold><italic>&#956;</italic></bold> and the positive (half-)integer <italic>s</italic>.

Russia

Anastasia A. Golubtsova

Mikhail A. Podoinitsyn

Continuous spin field in the <bold>AdS<inf>6</inf></bold> space

We report an experimental investigation of an unexplored breakup pathway of 6Li proceeding via one-proton stripping to the unbound 5He nucleus, followed by its decay into <math altimg='si22.svg'><mrow><mi>&#945;</mi><mo linebreak='goodbreak'>+</mo><mi>n</mi></mrow></math>, in the 6Li + 112Sn reaction at <math altimg='si3.svg'><mrow><msub><mi>E</mi><mrow><mrow><mi mathvariant='normal'>b</mi></mrow><mi>e</mi><mi>a</mi><mi>m</mi></mrow></msub><mo linebreak='goodbreak'>=</mo><mn>30</mn></mrow></math> MeV. Coincident <italic>&#945;</italic>- <italic>n</italic> events were measured using an array of silicon strip telescopes in conjunction with liquid scintillator neutron detectors. Successive kinematical cuts on the reconstructed projectile-like, fragment energies and Q-values enabled a clear separation of contributions arising purely through 5He <math altimg='si6.svg'><mrow><mo>&#8594;</mo><mi>&#945;</mi><mo linebreak='goodbreak'>+</mo><mi>n</mi></mrow></math> from competing processes such as evaporation following complete and incomplete fusion. The resultant relative energy distributions exhibit a pronounced peak at 0.84 MeV, indicating sequential breakup through the first unbound resonance 5He(3/2 <math altimg='si23.svg'><msup><mrow /><mo>&#8722;</mo></msup></math>) and show good agreement with Monte-Carlo simulations. Absolute breakup cross-sections for the ( 6Li, 5He&#8239;&#8594;&#8239; <italic>&#945;n</italic>) channel are determined using the efficiency-corrected yields. In addition, angular distributions for elastic scattering and breakup cross sections are interpreted within coupled-channels (CDCC+CRC) framework. The present results provide valuable insight into transfer-induced breakup dynamics of weakly bound nuclei near the Coulomb barrier.

India

Tanya Singh

S. Santra

P.C. Rout

A. Pal

A. Baishya

H. Kumawat

T. Santhosh

M. Meher

Jyotisankar Das

Ramandeep Gandhi

Sequential breakup of 6Li via ( 6Li, 5He <math altimg='si6.svg'><mrow><mo>&#8594;</mo><mi>&#945;</mi><mo linebreak='goodbreak'>+</mo><mi>n</mi></mrow></math>) reaction

An analysis of the flavour structure of dimension-6 effective field theory (EFT) operators in multilepton final states is presented, focusing on the interactions of quarks with Z bosons. For the first time, the flavour structure of these operators is disentangled by simultaneously probing the interactions with different quark generations. The analysis targets the associated production of a top quark pair and a Z boson, as well as diboson processes in final states with at least three leptons, which can be electrons or muons. The data were recorded by the CMS experiment in the years 2016–2018 in proton-proton collisions at a centre-of-mass energy of 13 TeV and correspond to an integrated luminosity of 138 fb . Consistency with the standard model of particle physics is observed and limits are set on the selected Wilson coefficients, split into couplings to light- and heavy-quark generations.

Armenia

A. Hayrapetyan

V. Makarenko

A. Tumasyan

Austria

W. Adam

J. Andrejkovic

L. Benato

T. Bergauer

M. Dragicevic

C. Giordano

P. Hussain

M. Jeitler

N. Krammer

A. Li

D. Liko

M. Matthewman

I. Mikulec

J. Schieck

D. Schwarz

R. Schöfbeck

M. Shooshtari

M. Sonawane

W. Waltenberger

C.E. Wulz

Belgium

T. Janssen

H. Kwon

D. Ocampo Henao

T. Laer

P. Mechelen

J. Bierkens

N. Breugelmans

J. D’Hondt

S. Dansana

A. Moor

M. Delcourt

F. Heyen

Y. Hong

P. Kashko

S. Lowette

I. Makarenko

D. Müller

J. Song

S. Tavernier

M. Tytgat

G. Onsem

S. Putte

D. Vannerom

B. Bilin

B. Clerbaux

A. Das

I. Bruyn

G. Lentdecker

H. Evard

L. Favart

P. Gianneios

A. Khalilzadeh

F. Khan

A. Malara

M. Shahzad

L. Thomas

M. Bemden

C. Vander Velde

P. Vanlaer

F. Zhang

M. Coen

D. Dobur

G. Gokbulut

J. Knolle

L. Lambrecht

D. Marckx

K. Skovpen

N. Bossche

J. Linden

J. Vandenbroeck

L. Wezenbeek

S. Bein

A. Benecke

A. Bethani

G. Bruno

A. Cappati

J. De Favereau De Jeneret

C. Delaere

A. Giammanco

A. Guzel

V. Lemaitre

J. Lidrych

P. Malek

P. Mastrapasqua

S. Turkcapar

Brazil

G. Alves

M. Barroso Ferreira Filho

E. Coelho

C. Hensel

T. Menezes De Oliveira

C. Mora Herrera

P. Rebello Teles

M. Soeiro

E. Tonelli Manganote

A. Vilela Pereira

W. Aldá Júnior

H. Brandao Malbouisson

Probing the flavour structure of dimension-6 EFT operators in multilepton final states in proton-proton collisions at $$ \sqrt{s}=13 $$ TeV

We consider a $$(1+1)$$ -dimensional theory with a single real scalar field $$\phi $$ whose kinematics is modified by a generalizing function $$f(\phi )$$ . After briefly reviewing its Bogomol’nyi–Prasad–Sommerfield (BPS) structure, we focus on a particular $$f(\phi )$$ to obtain analytic BPS double-kink solutions in three different models governed by the $$\phi ^4$$ , $$\phi ^6$$ , and sine-Gordon superpotentials. In all cases, the resulting double-kinks approach the vacuum values by following an exponential decay, with the generalizing function controlling its dependence on $\textit{x}$ and mass. We also calculate the BPS bound explicitly and study how the double kinks behave near the origin. The energy distribution of the novel BPS states engenders symmetric two-lump profiles for the $$\phi ^4$$ and sine-Gordon superpotentials. Whereas, for the $$\phi ^6$$ superpotential, the BPS energy profiles form asymmetric two-lumps.

R. Casana

E. Hora

Fabiano Simas

Exact BPS double-kinks in generalized $$\phi ^4$$ , $$\phi ^6$$ and sine-Gordon models

Pulsars convert a significant fraction of their total spin-down power into very high-energy electrons, leading to the formation of TeV halos. While these halos are well characterized at TeV energies, it remains unclear whether pulsars also accelerate electrons efficiently at lower energies and how these particles propagate through their surrounding environments. We aim to test whether synchrotron emission from $$\sim 50$$ – $$300 \, \textrm{GeV}$$ electrons around the Geminga pulsar can be detected in the frequency range observed by the Planck satellite. This would help constrain low-energy particle acceleration and diffusion in the vicinity of pulsars. We model the expected synchrotron emission from Geminga’s TeV halo based on various diffusion and injection spectrum scenarios and compare these predictions to publicly available multi-frequency Planck data. We find no conclusive evidence of spatially extended synchrotron emission associated with Geminga in any of Planck’s frequency bands. Our calculations show that even under favorable diffusion and injection conditions, the predicted synchrotron flux lies well below Planck’s measured background levels.

United States

D. Hooper

E. Pinetti

A. Sokolenko

Searching for synchrotron emission from the geminga TeV halo using the planck satellite

The competition between the breakup channels in the 6Li + 209Bi fusion reaction at the above-barrier energies has been investigated using a classical dynamic model. By incorporating the breakup processes from the short-lived nucleus formed via direct excitation and <italic>n</italic>-stripping, the model provides a comprehensive description of both complete and incomplete fusion cross sections. Although the <italic>n</italic>-stripping channel exhibits a higher probability, it contributes less to the complete fusion cross section compared to the direct excitation channel. An unexpected behavior was observed in incomplete fusion at the above barrier energies: the light-fragment capture predominantly occurs near the critical angular momentum, while the <italic>&#945;</italic> capture is favored at lower angular momenta, particularly in cases with large mass asymmetry between the two fragments. These findings provide further insight into the origin of fusion suppression in reactions involving weakly bound nuclei.

China

Kai-Xuan Cheng

Chun-Wang Ma

Mechanism of breakup channel competition in the 6Li+ 209Bi system at above-barrier energies

In this work, I discuss neutron stars with hyperons and antikaon condensate. To fix their coupling constants with the vector mesons of the quantum hadrodynamics, I use a unified scheme imposing that the Yukawa coupling is an invariant under SU(3) and SU(6) groups. Combining with the G-parity, I show that some expected results of the kaon and antikaon interaction with the nucleus are reobtained. In the same sense, the naive quark-isospin counting rule is restored in the SU(6) limit. Furthermore, the G-parity combined with the SU(3) gives us a clear picture of the role played by each meson in the kaon condensation. Numerical results show that the presence of antikaons severely compromises the stiffening of the equation of state by breaking the SU(6) symmetry.

Luiz L. Lopes

Baryon and pseudoscalar meson octets within a unified broken SU(6) symmetry

There exists a rare class of R-symmetry gauged $\textit{N}$ = (1$\textit{,}$ 0) supergravities in six dimensions with gauge group $\textit{G}$ × $\textit{U}$(1) , where $\textit{G}$ is semisimple with rank greater than one, and the number of tensor multiplets $\textit{n}$ = 1, which are free from all local anomalies. We find new members of this family, in which $\textit{G}$ contains up to four factors. We study the global anomalies of these models in a framework in which the Dirac quantization of the anomaly coefficients and the well-definedness of the Green-Schwarz anomaly counterterm in generic backgrounds play key roles, and we apply the anomaly freedom criteria that takes this into account as formulated by Monnier and Moore in $\textit{Commun. Math. Phys.}$ (2019) 963. To this end we use the result derived by Yuji Tachikawa in the appendix which states that the spin cobordism group $${\Omega }_{7}^{\text{Spin}}(BG)$$ vanishes for $\textit{G}$ = G × ⋯ × G where G is $\textit{U}$(1) or any simple simply-connected non-Abelian compact Lie group. We also require correct sign for the vector field kinetic terms, and positive Gauss-Bonnet term. We find that among the models considered here only one of them fails to satisfy all the stated criteria. We also find that, in general, the requirement that the anomaly coefficients defined by the factorized anomaly polynomial are elements of a unimodular charge lattice imposes a constraint on the number of vector multiplets given by $\textit{n}$ = 8 mod 12 for U(1) , and $\textit{n}$ = 60 for Sp(1) gauged models.

K. Becker

E. Sezgin

D. Tennyson

Japan

Y. Tachikawa

Global anomalies in 6$\textit{D}$ gauged supergravities

We investigate photon, pion, and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>ρ</mi></mrow></math>-meson production from proton synchrotron radiation in the presence of strong magnetic fields. The proton decay widths and the luminosities of the emitted particles are calculated within a relativistic quantum framework that incorporates Landau quantization. A scaling rule is derived for the transition probability between different Landau levels. This allows an evaluation of transitions for extremely high Landau numbers exceeding <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mn>10</mn><mn>15</mn></msup></math>. Furthermore, we calculate the momentum distribution of the emitted particles by properly including the proton recoil effect associated with particle emission. The results differ significantly from conventional semiclassical approaches.

Tomoyuki Maruyama

A. Baha Balantekin

South Korea

Myung-Ki Cheoun

Akira Dohi

Ryo Higuchi

Toshitaka Kajino

Grant J. Mathews

High energy particle production from proton synchrotron radiation in strong magnetic fields in relativistic quantum field theory

We report a laboratory search for ultralight dark photon dark matter using a single-site, two-sensor array of commercial scalar optically pumped magnetometers. In the low-frequency regime where the Earth–ionosphere system acts as an electromagnetic transducer, the expected magnetic signal is a narrow-band triplet of frequencies. This signature consists of a central peak at the dark photon’s Compton frequency, accompanied by two sidebands shifted by Earth’s sidereal rotation frequency. Because scalar magnetometers measure field magnitude, the observable signal is the projection of the oscillating dark photon magnetic field onto the direction of the large, local geomagnetic field. This preserves the crucial triplet signature in the resulting time series data. Analyzing 10.5 h of continuous data, we construct a six-channel complex data vector by evaluating the discrete-time Fourier transform for both sensors directly at the three physical frequencies of the signal triplet. Assuming complex-Gaussian noise, we develop a likelihood framework to set robust, frequency-resolved upper limits on the kinetic-mixing parameter <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>ϵ</mi></mrow></math>, which governs the coupling between Standard Model photons and dark photons. Within the mass range <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>4</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>15</mn></mrow></msup><mtext> </mtext><mtext> </mtext><mi>eV</mi><mo>≲</mo><msub><mi>m</mi><msup><mi>A</mi><mo>′</mo></msup></msub><mo>≲</mo><mn>3</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>14</mn></mrow></msup><mtext> </mtext><mtext> </mtext><mi>eV</mi></math>, we obtain the most stringent direct laboratory limits to date on the kinetic-mixing parameter, which are complementary to existing astrophysical bounds, including those inferred from observations of the Leo T dwarf galaxy.

Germany

Peisen Zhao

Ole Behrens

Maja Benning

Peter Fierlinger

Xuefen Han

Maximilian Huber

Florian Kuchler

Australia

Yevgeny V. Stadnik

Philipp Wunderl

Scalar-magnetometer search for ultralight dark photon dark matter with a single-site, two-sensor array: A 6-channel discrete-time Fourier transform likelihood analysis with scalar optically pumped magnetometers