<p>We introduce <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>w</mi><mi>i</mi></msub><msub><mi>f</mi><mi>i</mi></msub></math> ensembles as a novel framework to obtain asymptotic frequentist uncertainties on density ratios, with a particular focus on neural ratio estimation in the context of high-energy physics. When the density ratio of interest is a likelihood ratio conditioned on parameters, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>w</mi><mi>i</mi></msub><msub><mi>f</mi><mi>i</mi></msub></math> ensembles can be used to perform simulation-based inference on those parameters. After training the basis functions <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>f</mi><mi>i</mi></msub><mo stretchy="false">(</mo><mi>x</mi><mo stretchy="false">)</mo></math>, uncertainties on the weights <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>w</mi><mi>i</mi></msub></math> can be straightforwardly propagated to the estimated parameters without requiring extraneous bootstraps. To demonstrate this approach, we present an application in quantum chromodynamics at the Large Hadron Collider, using <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>w</mi><mi>i</mi></msub><msub><mi>f</mi><mi>i</mi></msub></math> ensembles to estimate the likelihood ratio between generated quark and gluon jets. We use this learned likelihood ratio to estimate the quark fraction in a synthetic mixed quark/gluon sample, showing that the resultant uncertainties empirically satisfy the desired coverage properties.</p>

United States

Sean Benevedes

Jesse Thaler

Frequentist uncertainties on neural density ratios with <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>w</mi><mi>i</mi></msub><mtext> </mtext><msub><mi>f</mi><mi>i</mi></msub></math> ensembles

We propose a systematic approach to calculating $\textit{n}$-point one-loop parametric conformal integrals in $\textit{D}$ dimensions which we call the reconstruction procedure. It relies on decomposing a conformal integral over basis functions which are generated from a set of master functions by acting with the cyclic group ℤ . In order to identify the master functions we introduce a bipartite Mellin-Barnes representation by means of splitting a given conformal integral into two additive parts, one of which can be evaluated explicitly in terms of multivariate generalized hypergeometric series.

Russia

Konstantin Alkalaev

Semyon Mandrygin

Multipoint conformal integrals in $\textit{D}$ dimensions. Part I. Bipartite Mellin-Barnes representation and reconstruction

<p>Motivated by the possible 95 GeV diphoton excess, we investigate the capability of the Type-I two-Higgs-doublet model (2HDM-I) to explain this signal under current theoretical and experimental constraints. Using full Monte Carlo simulations for the process of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>p</mi><mi>p</mi><mo stretchy="false">→</mo><mi>t</mi><mo stretchy="false">(</mo><mo stretchy="false">→</mo><msup><mi>W</mi><mo>+</mo></msup><mi>b</mi><mo stretchy="false">)</mo><mover accent="true"><mi>t</mi><mo stretchy="false">¯</mo></mover><mo stretchy="false">(</mo><mo stretchy="false">→</mo><msup><mi>W</mi><mo>−</mo></msup><mover accent="true"><mi>b</mi><mo stretchy="false">¯</mo></mover><mo stretchy="false">)</mo><mi>h</mi><mo stretchy="false">(</mo><mo stretchy="false">→</mo><mi>γ</mi><mi>γ</mi><mo stretchy="false">)</mo></math>, we evaluate the discovery potential of a 95 GeV Higgs boson at future colliders. Direct Higgs searches strongly constrain the parameter <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>α</mi></math>, excluding the region with <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>α</mi><mo>≲</mo><mn>0.95</mn></math>. Monte Carlo results indicate that a minimum cross section of 0.3 fb is required to achieve a <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>5</mn><mi>σ</mi></math> signal statistical significance at the high-luminosity LHC (HL-LHC) with <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>L</mi><mo>=</mo><mn>3</mn><mtext> </mtext><mtext> </mtext><msup><mi>ab</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>. For the same luminosity, high-energy LHC (HE-LHC) and future circular collider-hadron-hadron (FCC-hh) require 0.67 fb and 2.36 fb, respectively. At the 14 TeV HL-LHC with an integrated luminosity of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>3</mn><mtext> </mtext><mtext> </mtext><msup><mi>ab</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>, parameter regions with <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>sin</mi><mo stretchy="false">(</mo><mi>β</mi><mo>−</mo><mi>α</mi><mo stretchy="false">)</mo><mo>≳</mo><mn>0.4</mn></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>sin</mi><mo stretchy="false">(</mo><mi>β</mi><mo>−</mo><mi>α</mi><mo stretchy="false">)</mo><mo>≳</mo><mn>0.25</mn></math> can be probed at the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>5</mn><mi>σ</mi></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>2</mn><mi>σ</mi></math> significance levels, respectively. At the 27 TeV HE-LHC with <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>L</mi><mo>=</mo><mn>10</mn><mtext> </mtext><mtext> </mtext><msup><mi>ab</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>, the sensitivity improves to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>sin</mi><mo stretchy="false">(</mo><mi>β</mi><mo>−</mo><mi>α</mi><mo stretchy="false">)</mo><mo>≳</mo><mn>0.25</mn></math> (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>5</mn><mi>σ</mi></math>) and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo>≳</mo><mn>0.15</mn></math> (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>2</mn><mi>σ</mi></math>). For the 100 TeV FCC-hh with <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>L</mi><mo>=</mo><mn>30</mn><mtext> </mtext><mtext> </mtext><msup><mi>ab</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>, even regions with <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>sin</mi><mo stretchy="false">(</mo><mi>β</mi><mo>−</mo><mi>α</mi><mo stretchy="false">)</mo><mo>≳</mo><mn>0.1</mn></math> or <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>sin</mi><mo stretchy="false">(</mo><mi>β</mi><mo>−</mo><mi>α</mi><mo stretchy="false">)</mo><mo>≲</mo><mo>−</mo><mn>0.05</mn></math> can be covered at the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>5</mn><mi>σ</mi></math> level. Parameter regions near <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>sin</mi><mo stretchy="false">(</mo><mi>β</mi><mo>−</mo><mi>α</mi><mo stretchy="false">)</mo><mo>≈</mo><mn>0</mn></math> remain challenging to probe in the diphoton channel, even with increased energy or luminosity.</p>

China

Yabo Dong

Kun Wang

Jingya Zhu

Probing a type I 2HDM light Higgs boson in the top-pair-associated diphoton channel

We propose a methodology to infer the reheat temperature ( <math altimg='si19.svg'><msub><mi>T</mi><mrow><mtext>R</mtext><mi>H</mi></mrow></msub></math>) of the Universe from the collider signal of freezing in dark matter (DM). We demonstrate it for the mono- <math altimg='si11.svg'><mi>&#947;</mi></math> signal at the electron-positron colliders, which indicates to a low-scale <math altimg='si19.svg'><msub><mi>T</mi><mrow><mtext>R</mtext><mi>H</mi></mrow></msub></math>, after addressing observed DM abundance, BBN, and other relevant constraints. The method can be used to correlate different reheating dynamics, DM models, and collider signals.

India

Basabendu Barman

Subhaditya Bhattacharya

Sahabub Jahedi

Dipankar Pradhan

Abhik Sarkar

Lepton collider as a window to reheating via freezing in dark matter detection. Part I

Cryogenic calorimeters are among the leading technologies for searching for rare events. The CUPID experiment is exploiting this technology to deploy a tonne-scale detector to search for neutrinoless double-beta decay of $$^{100}$$ Mo. The CUPID collaboration proposed an innovative approach to assembling cryogenic calorimeters in a stacked configuration, held in position solely by gravity. This gravity-based assembly method is unprecedented in the field of cryogenic calorimeters and offers several advantages, including relaxed mechanical tolerances and simplified construction. To assess and optimize its performance, we constructed a medium-scale prototype hosting 28 Li $$_2$$ MoO $$_4$$ crystals and 30 Ge light detectors, both operated as cryogenic calorimeters at the Laboratori Nazionali del Gran Sasso (Italy). Despite an unexpected excess of noise in the light detectors, the results of this test proved (i) a thermal stability better than ±0.5 mK at 10 mK, (ii) a good energy resolution of Li $$_2$$ MoO $$_4$$ cryogenic calorimeters, (6.6 ± 2.2) keV FWHM at 2615 keV, and (iii) a Li $$_2$$ MoO $$_4$$ light yield measured by the closest light detector of 0.36 keV/MeV, sufficient to guarantee the particle identification requested by CUPID.

K. Alfonso

France

A. Armatol

C. Augier

F. Avignone

Italy

O. Azzolini

A. Barabash

G. Bari

A. Barrera

D. Baudin

F. Bellini

G. Benato

L. Benussi

V. Berest

M. Beretta

L. Bergé

M. Bettelli

M. Biassoni

J. Billard

F. Boffelli

V. Boldrini

E. Brandani

C. Brofferio

C. Bucci

M. Buchynska

J. Camilleri

A. Campani

J. Cao

Switzerland

C. Capelli

S. Capelli

V. Caracciolo

L. Cardani

P. Carniti

N. Casali

E. Celi

C. Chang

M. Chapellier

H. Chen

D. Chiesa

D. Cintas

M. Clemenza

I. Colantoni

S. Copello

O. Cremonesi

R. Creswick

A. D’Addabbo

I. Dafinei

Ukraine

F. Danevich

F. Dominicis

M. Jesus

P. Marcillac

S. Dell’Oro

F. Domizio

S. Lorenzo

V. Dompe

A. Drobizhev

L. Dumoulin

G. Fantini

M. Idrissi

M. Faverzani

E. Ferri

F. Ferri

F. Ferroni

E. Figueros-Feliciamo

J. Formaggio

A. Franceschi

S. Fu

B. Fujikawa

J. Gascon

S. Ghislandi

A. Giachero

M. Girola

L. Gironi

A. Giuliani

P. Gorla

C. Gotti

C. Grant

P. Gras

Germany

P. Guillaumon

T. Gutierrez

K. Han

E. Hansen

K. Heeger

D. Helis

H. Huang

M. Hurst

L. Imbert

A. Juillard

G. Karapetrov

G. Keppel

H. Khalife

V. Kobychev

Yu. Kolomensky

R. Kowalski

H. Lattaud

M. Lefevre

M. Lisovenko

R. Liu

Y. Liu

P. Loaiza

L. Ma

A gravity-based mounting approach for large-scale cryogenic calorimeter arrays

We classify the physical operators of the most general bosonic effective gauge theory up to dimension six using on-shell methods. Based on this classification, we compute the complete one-loop anomalous dimension employing both on-shell unitarity-based and geometric techniques. Our analysis fully accounts for the mixing of operators with different dimensions. The results broadly apply to any Effective Field Theory with arbitrary gauge symmetry and bosonic degrees of freedom. To illustrate their utility, we perform a complete cross-check of results on the renormalization of the Standard Model Effective Field Theory (SMEFT), $\textit{O}$($\textit{n}$) scalar theory, and the SMEFT extended with an axion-like particle. Additionally, we present new results for axion-like particles with CP-violating interactions.

Jason Aebischer

Luigi Bresciani

Nudžeim Selimović

Anomalous dimension of a general effective gauge theory. Part I. Bosonic sector

We introduce the concept of symmetry packaging for quantum field excitations: in a quantum field theory with a gauge group <italic>G</italic>, every local creation operator carries its full set of internal quantum numbers (IQNs) as a single irreducible <italic>G</italic>-block and forbids any partial factorization. We elevate this observation to a symmetry packaging principle, which asserts that packets of IQNs remain intact throughout all physical processes. We analyze a quantum-field excitation in six successive stages: (1) particle creation/annihilation, (2) hybridization with gauge-blind external degrees of freedom (DOFs), (3) tensor-product assembly, (4) isotypic decomposition, (5) packaged superposition/entanglement, and (6) local Gauge-Invariance constraint. We show that packaging survives every stage and culminates in a gauge-invariant physical Hilbert space. These stages unfold within a three packaging layer hierarchy (raw-Fock &#8594; isotypic &#8594; physical) with distinct packaging characters. Packaging alone reproduces familiar charge-superselection rules and, within any fixed-charge sector, admits a new class of packaged entangled states where internal and external DOFs are inseparably locked. We derive necessary and sufficient conditions for such superpositions and show that packaged irreps behave as noise-protected logical qudits. This framework unifies representation theory, superselection, and entanglement under a single mathematical roof and provides a roadmap for constructing and manipulating packaged states in any gauge theory.

Canada

Rongchao Ma

Symmetry packaging I: Irreducible representation blocks, superselection, and packaged entanglement in quantum field theory

The Frolov black hole (BH) is a charged extension of the Hayward BH, having regularity at the central point <math altimg='si1.svg'><mi>r</mi><mo linebreak='goodbreak' linebreakstyle='after'>=</mo><mn>0</mn></math> and an asymptotically Schwarzschild form for large values of <italic>r</italic>. Such a BH is parameterized by a length scale parameter, <math altimg='si2.svg'><msub><mrow><mi>&#945;</mi></mrow><mrow><mn>0</mn></mrow></msub></math>. In this paper, we analyze the thermodynamic properties, null and timelike geodesics, and shadows of a Frolov BH immersed in a quintessence field. Our results indicate that the smaller BH is locally thermodynamically stable yet globally unstable at all horizon radii. Neither the quintessence parameter nor the other model parameters like the charge <italic>q</italic> and length scale parameter <math altimg='si2.svg'><msub><mrow><mi>&#945;</mi></mrow><mrow><mn>0</mn></mrow></msub></math> change this global instability. We extend the study of the null and timelike geodesics to the vicinity of the BH by analyzing how the geodesic motion depends on the model parameters. Finally, we analyze the shadow of the BH system and find that the shadow radii are sensitively dependent on model parameters. In contrast, the influence of the quintessence parameter itself on the size of the shadow is found to be rather weak.

Mrinnoy M. Gohain

Kalyan Bhuyan

Rajnandini Borgohain

Tonmoyee Gogoi

Kakoli Bhuyan

Prabwal Phukon

Frolov black hole surrounded by quintessence - I: Thermodynamics, geodesics and shadows

In a previous paper, we proposed an entropy function for AdS BPS black holes in M-theory with general magnetic charges, resolving a long-standing puzzle about baryonic charges in three-dimensional holography and offering a prediction for the large-$\textit{N}$ limit of several partition functions whose saddle points have yet to be found. The entropy function is constructed from the master volume of the internal manifold. In this paper, we prove that the entropy of a general class of black holes based on toric geometry can indeed be reformulated as an $$ \mathcal{I} $$ -extremization problem, and we provide a set of examples. As an aside, we also simplify existing proofs of the equivalence between $\textit{a}$-, $\textit{c}$-, and $\textit{F}$-extremizations and their gravitational duals.

United Kingdom

Seyed Hosseini

Alberto Zaffaroni

$$ \mathcal{I} $$ -extremization for AdS

We propose a minimal scenario for light thermal dark matter (DM) in sub-GeV to GeV range by incorporating a scalar singlet DM in a type-I seesaw scenario extended by an additional Higgs doublet $\textit{ϕ}$ . The latter permits efficient annihilation of light scalar DM into leptonic final states including right-handed neutrinos (RHN). We keep the charged fermion as well as neutral fermion final states in forbidden regime to avoid bounds from indirect search as well as cosmic microwave background (CMB) data. After studying the purely forbidden DM scenario with neutral and charged fermion final states separately, we discuss the interplay of forbidden and non-forbidden channels in generating light thermal DM relic by considering neutral fermions in non-forbidden mode due to relatively weaker constraints. The model can also explain the anomalous magnetic moment of muon, W-mass anomaly and saturate experimental bounds on charged lepton flavour violation and DM direct detection while offering tantalising detection prospects of RHN, the mass of which is kept approximately in the same range as DM.