The intense photon fluxes from relativistic nuclei provide an opportunity to study photonuclear interactions in ultraperipheral collisions. In particular, it allows for the investigations of excited, light-flavour vector mesons. The measurement of coherently photoproduced <math altimg='si6.svg'><mrow><msup><mi>&#960;</mi><mo>+</mo></msup><msup><mi>&#960;</mi><mo>&#8722;</mo></msup><msup><mi>&#960;</mi><mo>+</mo></msup><msup><mi>&#960;</mi><mo>&#8722;</mo></msup></mrow></math> final states in ultraperipheral Pb&#8211;Pb collisions at <math altimg='si7.svg'><mrow><msqrt><msub><mi>s</mi><mtext>NN</mtext></msub></msqrt><mspace width='0.33em' /><mo linebreak='goodbreak'>=</mo><mspace width='0.33em' /><mn>5.02</mn></mrow></math> TeV is presented for the first time. The cross section, d <italic>&#963;</italic>/d <italic>y</italic>, times the branching ratio ( <math altimg='si8.svg'><mrow><mi>&#961;</mi><mo>&#8594;</mo><msup><mi>&#960;</mi><mo>+</mo></msup><msup><mi>&#960;</mi><mo>+</mo></msup><msup><mi>&#960;</mi><mo>&#8722;</mo></msup><msup><mi>&#960;</mi><mo>&#8722;</mo></msup></mrow></math>) is found to be 47.8&#8239;&#177;&#8239;2.3&#8201;(stat.)&#8239;&#177;&#8239;7.7&#8201;(syst.) mb in the rapidity interval | <italic>y</italic>|&#8239;&lt;&#8239;0.5. The invariant mass distribution is not well described with a single Breit-Wigner resonance without an interference term. Including interference with a non-resonant contribution results in the mass and width values being too far from those reported in PDG, while the production of two interfering resonances, <italic>&#961;</italic>(1450) and <italic>&#961;</italic>(1700), also provides a good description of the data. The values of the masses ( <italic>m</italic>) and widths (&#915;) of the resonances extracted from the fit assuming two interfering resonances are <math altimg='si9.svg'><mrow><msub><mi>m</mi><mn>1</mn></msub><mo linebreak='goodbreak'>=</mo><mn>1385</mn><mo>&#177;</mo><mn>14</mn><mspace width='0.33em' /><mrow><mo mathvariant='normal'>(</mo><mtext>stat</mtext><mo>.</mo><mo>)</mo></mrow><mo>&#177;</mo><mn>3</mn><mspace width='0.33em' /><mrow><mo mathvariant='normal'>(</mo><mtext>syst</mtext><mo>.</mo><mo>)</mo></mrow></mrow></math> MeV/ <italic>c</italic> 2, <math altimg='si10.svg'><mrow><msub><mstyle mathvariant='normal'><mi>&#915;</mi></mstyle><mn>1</mn></msub><mo linebreak='goodbreak'>=</mo><mn>431</mn><mo>&#177;</mo><mn>36</mn><mspace width='0.33em' /><mrow><mo mathvariant='normal'>(</mo><mtext>stat</mtext><mo>.</mo><mo>)</mo></mrow><mo>&#177;</mo><mn>82</mn><mspace width='0.33em' /><mrow><mo mathvariant='normal'>(</mo><mtext>syst</mtext><mo>.</mo><mo>)</mo></mrow></mrow></math> MeV/ <italic>c</italic> 2, <math altimg='si11.svg'><mrow><msub><mi>m</mi><mn>2</mn></msub><mo linebreak='goodbreak'>=</mo><mn>1663</mn><mo>&#177;</mo><mn>13</mn><mspace width='0.33em' /><mrow><mo mathvariant='normal'>(</mo><mtext>stat</mtext><mo>.</mo><mo>)</mo></mrow><mo>&#177;</mo><mn>22</mn><mspace width='0.33em' /><mrow><mo mathvariant='normal'>(</mo><mtext>syst</mtext><mo>.</mo><mo>)</mo></mrow></mrow></math> MeV/ <italic>c</italic> 2 and <math altimg='si12.svg'><mrow><msub><mstyle mathvariant='normal'><mi>&#915;</mi></mstyle><mn>2</mn></msub><mo linebreak='goodbreak'>=</mo><mn>357</mn><mspace width='0.33em' /><mo>&#177;</mo><mn>31</mn><mspace width='0.33em' /><mrow><mo mathvariant='normal'>(</mo><mtext>stat</mtext><mo>.</mo><mo>)</mo></mrow><mo>&#177;</mo><mn>49</mn><mspace width='0.33em' /><mrow><mo mathvariant='normal'>(</mo><mtext>syst</mtext><mo>.</mo><mo>)</mo></mrow></mrow></math> MeV/ <italic>c</italic> 2, respectively. The measured cross sections times the branching ratios are compared to recent theoretical predictions.

France

S. Acharya

Czechia

D. Adamová

India

A. Agarwal

Switzerland

G. Aglieri Rinella

Italy

L. Aglietta

M. Agnello

N. Agrawal

Z. Ahammed

S. Ahmad

South Korea

S.U. Ahn

Slovakia

I. Ahuja

A. Akindinov

Germany

V. Akishina

M. Al-Turany

D. Aleksandrov

B. Alessandro

China

H.M. Alfanda

Mexico

R. Alfaro Molina

B. Ali

A. Alici

United States

N. Alizadehvandchali

A. Alkin

Norway

J. Alme

G. Alocco

T. Alt

A.R. Altamura

I. Altsybeev

J.R. Alvarado

M.N. Anaam

Romania

C. Andrei

United Kingdom

N. Andreou

A. Andronic

E. Andronov

V. Anguelov

F. Antinori

P. Antonioli

N. Apadula

L. Aphecetche

H. Appelsh

C. Arata

S. Arcelli

M. Aresti

R. Arnaldi

Brazil

J.G.M.C.A. Arneiro

I.C. Arsene

M. Arslandok

A. Augustinus

R. Averbeck

M.D. Azmi

Japan

H. Baba

A. Badal

J. Bae

Y.W. Baek

X. Bai

R. Bailhache

Y. Bailung

R. Bala

A. Balbino

A. Baldisseri

Poland

B. Balis

D. Banerjee

Z. Banoo

V. Barbasova

F. Barile

L. Barioglio

Greece

M. Barlou

B. Barman

Hungary

G.G. Barnaf

L.S. Barnby

E. Barreau

V. Barret

L. Barreto

C. Bartels

K. Barth

E. Bartsch

N. Bastid

Sweden

S. Basu

G. Batigne

D. Battistini

B. Batyunya

D. Bauri

Peru

J.L. Bazo Alba

Denmark

I.G. Bearden

C. Beattie

P. Becht

D. Behera

I. Belikov

A.D.C. Bell Hechavarria

F. Bellini

R. Bellwied

S. Belokurova

L.G.E. Beltran

Y.A.V. Beltran

G. Bencedi

A. Bensaoula

S. Beole

Y. Berdnikov

A. Berdnikova

L. Bergmann

M.G. Besoiu

Exclusive photoproduction of excited <italic>&#961;</italic> mesons decaying to four pions in ultraperipheral Pb&#8211;Pb collisions at <math altimg='si5.svg'><mrow><msqrt><msub><mtext mathvariant='bold-italic'>s</mtext><mtext>NN</mtext></msub></msqrt><mo linebreak='goodbreak'>=</mo><mn mathvariant='bold'>5</mn><mo>.</mo><mn mathvariant='bold'>02</mn></mrow></math> TeV

In the Standard Model, the $$c \rightarrow u\nu {\bar{\nu }}$$ transition arises only at the one-loop level, leading to extremely suppressed branching ratios for the corresponding three-body decays of charmed hadrons. This suppression motivates the search for possible enhancements from physics beyond the Standard Model. In this work, we study the contributions to the $$c \rightarrow u\nu {\bar{\nu }}$$ transition from the $$R^{a2}_2$$ scalar leptoquark predicted in the Non-Minimal SU(5) GUT framework. We derive constraints on the model parameters using the recent BESIII results on $$D^0 \rightarrow \pi ^0\nu {\bar{\nu }}$$ and available data on $$D^0$$ – $$\bar{D}^0$$ mixing. Additional bounds from direct LHC searches for scalar leptoquarks, lepton flavor violation processes, and the LHCb upper limit on $$\mathcal {B}(D^0 \rightarrow \mu ^+ \mu ^-)$$ are also taken into account. After imposing all constraints, we show that the branching ratios of the three-body charmed hadron decays with missing energy can be enhanced up to $${{\mathcal {O}}}(10^{-6})$$ .

Türkiye

Gaber Faisel

Investigating three body charm hadron decays with missing energy within non-minimal SU(5)

We have studied an <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>S</mi><mi>O</mi><mo stretchy="false">(</mo><mn>4</mn><mo stretchy="false">)</mo></math> gauged <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>O</mi><mo stretchy="false">(</mo><mn>5</mn><mo stretchy="false">)</mo></math> Skyrmion on <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mi mathvariant="normal">I</mi><mspace depth="0.0ex" height="0.0ex" width="-0.2em"></mspace><mi mathvariant="normal">R</mi></mrow><mrow><mn>4</mn></mrow></msup></mrow></math>, which can be seen as a static soliton in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>4</mn><mo>+</mo><mn>1</mn></math> dimensions. This is a sequel of the known <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>S</mi><mi>O</mi><mo stretchy="false">(</mo><mi>D</mi><mo stretchy="false">)</mo></math> gauged <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>O</mi><mo stretchy="false">(</mo><mi>D</mi><mo>+</mo><mn>1</mn><mo stretchy="false">)</mo></math> Skyrmions on <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mi mathvariant="normal">I</mi><mspace depth="0.0ex" height="0.0ex" width="-0.2em"></mspace><mi mathvariant="normal">R</mi></mrow><mrow><mi>D</mi></mrow></msup></mrow></math> in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>D</mi><mo>=</mo><mn>2</mn></math> and in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>D</mi><mo>=</mo><mn>3</mn></math>, which are likewise localized to an absolute scale and topologically stable, their energies being bounded below by the winding number. In the absence of an analytic proof of existence, some such solutions are constructed numerically. Two families of solutions are found, of which only one possesses a gauge decoupling limit. The curvatures of both of these solutions decay as <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>r</mi><mrow><mo>−</mo><mn>3</mn></mrow></msup></math>, a property they share with the Yang-Mills instantons on <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mi mathvariant="normal">I</mi><mspace depth="0.0ex" height="0.0ex" width="-0.2em"></mspace><mi mathvariant="normal">R</mi></mrow><mrow><mn>4</mn></mrow></msup></mrow></math>.

Spain

Francisco Navarro-Lérida

Ireland

D.H. Tchrakian

SO(4) gauged O(5) Skyrmion on <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi mathvariant="normal">R</mi><mn>4</mn></msup></math>

We study the proposed integrable spin chain formulation of Jordanian deformations of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>AdS</mi><mn>5</mn></msub><mo>×</mo><msup><mi>S</mi><mn>5</mn></msup></math> superstring, realized via Drinfel’d twists. Among these models, we first identify a unique supergravity deformation confined to an <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>S</mi><mi>L</mi><mo stretchy="false">(</mo><mn>2</mn><mo>,</mo><mi mathvariant="double-struck">R</mi><mo stretchy="false">)</mo></math> sector and with constant dilaton. We then develop a general framework for closed Drinfel’d twisted spin chains and construct an explicit map to undeformed models with twisted-boundary conditions. Applied to the noncompact <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>XXX</mi><mrow><mo>−</mo><mn>1</mn><mo>/</mo><mn>2</mn></mrow></msub></math> spin chain, the Jordanian twist breaks the Cartan generator labeling magnon excitations, obstructing the standard Bethe methods. Instead, using the twisted-boundary formulation, we initiate the spectral problem based on a residual root generator both in the continuum limit and for short chains. We find that the ground state is nontrivially deformed, and is in agreement with the classical string result, while our analysis does not capture higher-spin excited states. We also study the asymptotics of the associated <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Q</mi></math> system, which is well behaved and compatible with the boundary twist. While a full understanding of the spectrum remains open, our work provides concrete steps toward a spectral description of non-Abelian twisted integrable models.

Sibylle Driezen

Adrien Molines

Jordanian spin chains for twisted strings in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>AdS</mi><mn>5</mn></msub><mo>×</mo><msup><mi>S</mi><mn>5</mn></msup></math>

The (Calibrated nuclear Recoils for Accurate Bolometry) project aims to precisely characterize the response of cryogenic detectors to sub-keV nuclear recoils of direct interest for coherent neutrino-nucleus scattering and dark matter search experiments. The method relies on the radiative capture of thermal neutrons in the target detector, resulting in a nuclear recoil with a well-defined energy. We present a new experimental setup installed at the TRIGA Mark-II reactor at Atominstitut (Vienna), providing a low intensity beam of thermal neutrons sent to the target cryogenic detector mounted inside a wet dilution refrigerator Kelvinox 100. After the presentation of all components of the setup we report the analysis of first commissioning data with CaWO $$_{4}$$ detectors of the experiment. They show stable operation of the cryostat and detectors on a week-scale. Due to an energy resolution currently limited to 20 eV we use neutron beam induced events at high energy, in the 10 to 100 keV range, to demonstrate the excellent agreement between the data and simulation and the accurate understanding of external background. Thanks to these data we also propose an updated decay scheme of the low-lying excited states of $$^{187}$$ W. Finally, we present the first evidence of neutron-capture induced coincidences between BaF $$_2$$ $$\gamma $$ -detectors installed around the dewar and the inner cryogenic detector. These promising results pave the way for an extensive physics program with various detector materials, like CaWO $$_{4}$$ , Al $$_{2}$$ O $$_{3}$$ , Ge and Si.

Austria

H. Abele

P. Ajello

A. Armatol

B. Arnold

J. Billard

E. Bossio

J. Burkhart

F. Cappella

N. Casali

R. Cerulli

J. Colas

J.P. Crocombette

G. Castello

M. Gallo Roccagiovine

S. Dorer

C. Doutre

A. Erhart

S. Fichtinger

M. Friedl

P. Garin

R. Gergen

C. Goupy

D. Hainz

D. Hauff

E. Jericha

M. Kaznacheeva

H. Kluck

T. Lasserre

D. Lhuillier

O. Litaize

P. Marcillac

S. Marnieros

R. Martin

E. Namuth

T. Ortmann

D. Poda

L. Peters

F. Reindl

W. Reindl

F. Rodari

J. Rothe

N. Schermer

J. Schieck

S. Schönert

C. Schwertner

G. Soum-Sidikov

R. Strauss

R. Thalmeier

L. Thulliez

C. Trunner

M. Vignati

M. Vivier

P. Wasser

A. Wex

The CRAB facility at the TU Wien TRIGA reactor: status and related physics program

In this paper, we continue our investigation of gravitational interactions for massive higher spins extending our previous work on massive spin 3/2 and spin 2 to massive spin 5/2, including partially massless and massless limits. We use the gauge invariant frame-like description for massive fields, both for general analysis of possible vertices and for constructing the minimal vertex (i.e. vertex containing standard minimal interactions and non-minimal interactions with a minimum number of derivatives). In particular, we show that there is a special point $\textit{m}$ = 4Λ, which corresponds to the boundary of a unitary allowed region in $\textit{dS}$ , where minimal interactions disappear, leaving only non-minimal ones.

Russia

Yu. Zinoviev

On massive higher spins and gravity. Part I. Spin 5/2

We propose a lattice formulation of four dimensional super Yang-Mills model with a twisted $\textit{N}$ = 4 supersymmetry in a manifestly gauge covariant manner. The formulation we employ here is a four dimensional extension of the manifestly gauge covariant method which was developed in our proposals of Dirac-Kähler twisted $\textit{N}$ = $\textit{D}$ = 2 and $\textit{N}$ = 4 $\textit{D}$ = 3 super Yang-Mills on a lattice. Twisted $\textit{N}$ = 4 supersymmetry algebra is geometrically realized on a four dimensional lattice with link supercharges and the use of link (anti-)commutators. Employing Grassmann parameters with link nature, we explicitly show that the resulting super Yang-Mills action is invariant under all the supercharges on a lattice without chiral fermion problems. As a group and algebraic interpretation of the link approach, we show that promoting bosonic supercovariant derivatives to their exponentials consistently with the lattice Leibniz rule naturally gives rise to the notion of gauge covariant link (anti-)commutators. This can be regarded as a fermionic decomposition of a Lie group element, which may provide a new methodology in super Lie group and super Lie algebra. We also provide a five dimensional lift-up of the formulation with exact $\textit{N}$ = 4 SUSY invariance on a five dimensional lattice.

Alessandro D’Adda

Gauge covariant link formulation of twisted $\textit{N}$ = $\textit{D}$ = 4 and $\textit{N}$ = 4 $\textit{D}$ = 5 super Yang-Mills on a lattice