We investigate the frame dependence of distribution functions within the framework of generalized chiral kinetic theory. Based on the derived transformation rules governing the choice of frame, we analytically obtain the global equilibrium solutions in the presence of vorticity and electromagnetic fields. Our results show that, under the assumption of varying electromagnetic fields, these equilibrium solutions can be uniquely determined.

China

Shu-Xiang Ma

Jian-Hua Gao

Frame dependence in generalized chiral kinetic theory * Supported in part by the National Natural Science Foundation of China (12575147, 12321005, 12175123)

A one-loop resummation scheme, inspired by Dyson–Schwinger (DS) formalism of strongly coupled quantum field theories, is applied to spin-1/2 magnetic monopoles (MMs), in the context of an effective field theory (EFT), invariant under the gauge group $$\mathrm U(1)_{em}\otimes U(1)^\prime $$ , where $$\mathrm U(1)^\prime $$ is a dual strongly coupled Abelian interaction, associated with a ‘dark photon’. The latter leads to a MM appearing as a limiting case of a ‘dyon’, with a tiny ‘electric charge’, compensated by a huge wave-function renormalization of the MM, thereby leading to a finite renormalized MM–photon coupling. An ultra-violet fixed point structure is found in the resummed theory, which is purely non-perturbative due to different boundary conditions of the resummation equations, compared to the weak coupling (perturbative) case. The renormalized coupling of the MM to the electromagnetic photon in the fixed-point theory is identified with the magnetic charge, compatible with the Dirac quantization condition. This provides for the first time a formal justification of the use of tree-level Drell–Yan and photon-fusion MM production processes in collider searches, and of the corresponding cross sections and MM mass bounds thereof. The latter provide a means to constrain the resummed-EFT parameters experimentally. The DS resummation applies here primarily to elementary MMs. However, this approach may also be applied to the last stage (collapse) of the formation of composite MM pairs at colliders, in case they behave as quantum excitations, with their core radius comparable to the Compton wavelength, thereby avoiding the extreme suppression of their production.

United Kingdom

Jean Alexandre

Spain

Greece

Nick Mavromatos

Vasiliki Mitsou

United States

Emanuela Musumeci

Magnetic-monopole resummation justifies perturbatively calculated collider production cross sections

A search is performed for a new resonance <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi></math> decaying into a Higgs boson and a new scalar boson <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Y</mi></math> (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>H</mi><mi>Y</mi></math>) including the case where <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Y</mi></math> is assumed to be a second Higgs boson (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>H</mi><mi>H</mi></math>), using proton-proton collision data collected at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>13</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></math>, corresponding to an integrated luminosity of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>138</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>. This study performs a comprehensive exploitation of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>b</mi><mi>b</mi><mi>Z</mi><mi>Z</mi></math> events, encompassing the following decay topologies. One <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>H</mi></math> candidate is identified through its decay into a bottom quark-antiquark pair, while the other <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>H</mi></math> or the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Y</mi></math> candidate is selected through its decay into a pair of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Z</mi></math> bosons. One <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Z</mi></math> boson is required to decay leptonically and the other, to decay into a pair of quarks or neutrinos. Events of interest are categorized based on the Lorentz boosts of the hadronically decaying <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>H</mi></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Z</mi></math> bosons. Machine-learning-based discriminants, together with the reconstructed resonance mass, are employed across the different categories to separate signal from backgrounds, and their corresponding distributions are included in a simultaneous fit. No significant deviations from the standard model predictions are observed. Upper limits at the 95% confidence level are set on the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>H</mi><mi>Y</mi></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>H</mi><mi>H</mi></math> production cross sections. For <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>H</mi><mi>Y</mi></math> production, the upper limit on the cross section of the process <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>p</mi><mi>p</mi><mo stretchy="false">→</mo><mi>X</mi><mo stretchy="false">→</mo><mrow><mi>H</mi><mi>Y</mi></mrow><mo stretchy="false">→</mo><mi>b</mi><mi>b</mi><mi>Z</mi><mi>Z</mi></math> ranges from 500 to 5 fb, with the most stringent constraints achieved for high-mass <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi></math> resonances and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Y</mi></math> masses near the threshold for decay into a pair of massive vector bosons. This is comparable to the sensitivity achieved in other analyses, which focus on <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>H</mi></math> decays to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>γ</mi><mi>γ</mi></math> or <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>τ</mi><mi>τ</mi></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Y</mi></math> decays into a pair of bottom quarks or massive vector bosons. For resonant <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>H</mi><mi>H</mi></math> production, the upper limit on the cross section of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>p</mi><mi>p</mi><mo stretchy="false">→</mo><mi>X</mi><mo stretchy="false">→</mo><mrow><mi>H</mi><mi>H</mi></mrow></math> production is 1 pb for a high-mass resonance.

Armenia

A. Hayrapetyan

V. Makarenko

A. Tumasyan

Austria

W. Adam

L. Benato

T. Bergauer

M. Dragicevic

P.S. Hussain

M. Jeitler

N. Krammer

A. Li

D. Liko

M. Matthewman

J. Schieck

R. Schöfbeck

M. Shooshtari

M. Sonawane

N. Van Den Bossche

W. Waltenberger

C.E. Wulz

Belgium

T. Janssen

H. Kwon

D. Ocampo Henao

T. Van Laer

P. Van Mechelen

D. Ahmadi

J. Bierkens

N. Breugelmans

J. D’Hondt

S. Dansana

A. De Moor

M. Delcourt

C. Gupta

F. Heyen

Y. Hong

P. Kashko

S. Lowette

I. Makarenko

S. Nandakumar

S. Tavernier

M. Tytgat

G.P. Van Onsem

S. Van Putte

D. Vannerom

A. Beshr

B. Bilin

F. Caviglia Roman

B. Clerbaux

A.K. Das

I. De Bruyn

G. De Lentdecker

E. Ducarme

H. Evard

L. Favart

A. Khalilzadeh

A. Malara

M.A. Shahzad

A. Sharma

L. Thomas

M. Vanden Bemden

C. Vander Velde

P. Vanlaer

F. Zhang

A. Cauwels

M. De Coen

D. Dobur

C. Giordano

G. Gokbulut

K. Kaspar

D. Kavtaradze

D. Marckx

K. Skovpen

A.M. Tomaru

J. van der Linden

J. Vandenbroeck

H. Aarup Petersen

S. Bein

A. Benecke

A. Bethani

G. Bruno

A. Cappati

J. De Favereau De Jeneret

C. Delaere

F. Gameiro Casalinho

A. Giammanco

A.O. Guzel

V. Lemaitre

J. Lidrych

P. Malek

S. Turkcapar

Brazil

G.A. Alves

M. Barroso Ferreira Filho

E. Coelho

C. Hensel

D. Matos Figueiredo

T. Menezes De Oliveira

C. Mora Herrera

P. Rebello Teles

M. Soeiro

E.J. Tonelli Manganote

Search for a new resonance decaying to a Higgs boson and a scalar boson in events with two <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>b</mi></math> jets and two <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Z</mi></math> bosons in proton-proton collisions at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>13</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></math>

We investigate the spreading of entanglement, and entanglement memory effects, in two-dimensional conformal field theory (CFT) propagating on evaporating black hole backgrounds. Memory effects leading to late-time spikes in mutual information for widely separated intervals are well known in CFTs admitting a quasiparticle description. In this work we examine the effect of black hole scrambling on late time mutual information spikes for disjoint intervals in free fermion CFT prepared in a thermofield double state. Late-time entanglement revival is driven by island-induced purification of modes in the union of the intervals. We show across two distinct 2D gravity models, Jackiw-Teitelboim (JT) gravity and the Russo-Susskind-Thorlacius (RST) model, that parametrically dialing up black hole scrambling time smooths out and suppresses entanglement spikes until they disappear at a critical scale, interpolating between free quasiparticle and maximal scrambling pictures. At the critical point, the interval lengths are exponential in black hole scrambling time. We further find a very closely related effect manifest as an entanglement dip for a single interval in a single-sided evaporating RST black hole.

Levy B.N. Batista

Nicolò Bragagnolo

Rhys Holmes

S. Prem Kumar

Entanglement revivals and scrambling for evaporating black holes

In this paper, we derive the upper bounds on the coupling of axionlike particles (ALPs) with photon as a function of the mass by considering axion-photon conversion in the Crab Nebula. Previous studies have not considered the influence of the magnetic field within the Crab Nebula. The magnetic field plays a crucial role through the synchrotron self-Compton process, in which high-energy electrons produce synchrotron radiation that is subsequently upscattered by the same electrons via inverse Compton scattering to generate <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>γ</mi></math> rays. Therefore, neglecting the magnetic field in modeling leads to theoretical inconsistencies. In this work, we investigate the significance of the magnetic field effect and demonstrate that even differences in magnetic field modeling can substantially alter the conversion probability. We thus, for the first time, point out that proper consideration of the magnetic field is essential in ALP searches using <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>γ</mi></math> rays from the Crab Nebula. The resulting constraints reach up to a coupling of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>g</mi><mrow><mi>a</mi><mi>γ</mi><mi>γ</mi></mrow></msub><mo>≲</mo><mn>1</mn><mo>×</mo><msup><mn>10</mn><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></math> for ALP masses in the range <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mn>10</mn><mrow><mo>−</mo><mn>10</mn></mrow></msup><mtext> </mtext><mtext> </mtext><mi>eV</mi><mo>≲</mo><msub><mi>m</mi><mi>a</mi></msub><mo>≲</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>6</mn></mrow></msup><mtext> </mtext><mtext> </mtext><mi>eV</mi></math>.

Japan

Kazunori Kohri

Haruki Takahashi

New constraints on axions with gamma-ray observations of the Crab Nebula

Recent lattice evidence may suggest the chiral phase transition in QCD is second order for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>N</mi></mrow><mrow><mi>f</mi></mrow></msub><mo>≥</mo><mn>2</mn></mrow></math> massless flavors. We constrain conformal field theory (CFT) descriptions of a critical line in temperature <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>T</mi></mrow></math> and imaginary baryon chemical potential <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>θ</mi></mrow><mrow><mi>B</mi></mrow></msub><mo>=</mo><mi>i</mi><msub><mrow><mi>μ</mi></mrow><mrow><mi>B</mi></mrow></msub><mo>/</mo><mi>T</mi></mrow></math>. An ’t Hooft anomaly at general <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>θ</mi><mi>B</mi></msub></math> constrains the transition even at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>θ</mi><mi>B</mi></msub><mo>=</mo><mn>0</mn></math>, leaving only three minimal scenarios. The best-motivated scenario for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>N</mi><mi>f</mi></msub><mo>≥</mo><mn>3</mn></math>, and perhaps also <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>N</mi><mi>f</mi></msub><mo>=</mo><mn>2</mn></math>, is beyond Ginzburg-Landau, featuring a conformal manifold of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>θ</mi><mi>B</mi></msub></math>-dependent universality classes with an exactly marginal operator related to baryon density.

Shi Chen

Aleksey Cherman

Robert D. Pisarski

Does Hot QCD Have a Conformal Manifold in the Chiral Limit?

We show that the direction of renormalization in effective field theory is constrained by fundamental principles in the infrared—unitarity, analyticity, and Lorentz invariance. Our theorem, in the spirit of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>a</mi></math> theorem in conformal field theory, determines the sign of the one-loop running of couplings in the forward limit, when one inserts two operators whose mass dimensions are identical and even. The theorem holds for a broad class of effective field theories with arbitrary ultraviolet completions. The constraint directly applies to linear positivity bounds derived using tree-level amplitudes in the infrared, providing a criterion for whether renormalization effects can preserve the positivity bounds or lead to their apparent violation. We discuss the phenomenological implications of our theorem in chiral perturbation theory and the Standard Model effective field theory, where our theorem is particularly constraining for the running at dimension eight. We provide several examples and show various extensions and applications even at dimension six.

Taiwan

You-Peng Liao

Jasper Roosmale Nepveu

Sweden

Chia-Hsien Shen

Positivity in the renormalization of effective field theory

The Wigner distributions (WDs) in boost-invariant longitudinal space for unpolarized, longitudinally polarized, and linearly polarized gluons within a proton are presented in the framework of the light-front gluon spectator model inspired by AdS/QCD. The boost-invariant longitudinal space defined by the coordinate <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>σ</mi><mo>=</mo><mfrac><mn>1</mn><mn>2</mn></mfrac><msup><mi>b</mi><mo>−</mo></msup><msup><mi>P</mi><mo>+</mo></msup></math>, can be accessed through the Fourier transformation over skewness <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>ξ</mi></math> to the gluon-gluon correlator of generalized transverse momentum dependent distributions (GTMDs). The model results for gluon WDs in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>σ</mi></math>-space show an oscillatory behavior analogous to the diffraction scattering of a wave in optics. The diffraction pattern is more sensitive to the momentum fraction <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>x</mi></math> and passively varies with the total energy transfer to the electron-proton scattering <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo>−</mo><mi>t</mi></math>, both of which are analogous to an effective slit width. The leading-twist gluon WDs in the impact-parameter space and their skewness sensitivity are investigated extensively for unpolarized, longitudinally polarized, and transversely polarized protons. The gluon spin-orbital angular momentum correlation is also reported and compared with existing models and lattice results.

India

 Sonia

Tanmay Maji

Hemant Kumar

Gluon Wigner distributions in boost-invariant longitudinal position space

We present a systematic study of the masses of light excited <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>q</mi><mover accent="true"><mi>q</mi><mo stretchy="false">¯</mo></mover></math> mesons using quantum chromodynamics (QCD) sum rules at next-to-leading order (NLO). To probe excited states, we construct several interpolating currents with covariant derivatives inserted. The calculation is carried out up to dimension-8 condensates, including NLO perturbative and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>m</mi><mo stretchy="false">⟨</mo><mover accent="true"><mi>q</mi><mo stretchy="false">¯</mo></mover><mi>q</mi><mo stretchy="false">⟩</mo></math> corrections. Employing Gaussian sum rules, we obtain several <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>J</mi><mi>P</mi></msup><mo>=</mo><msup><mn>2</mn><mo>±</mo></msup></math> nonets with masses that agree well with experiments. Several <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>J</mi><mo>=</mo><mn>0</mn></math>, 1 states compatible with experiments are also obtained using both Gaussian and Laplace sum rules. In particular, the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>J</mi><mrow><mi>P</mi><mi>C</mi></mrow></msup><mo>=</mo><msup><mn>2</mn><mrow><mo>+</mo><mo>+</mo></mrow></msup></math> current couples to two distinct <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mn>2</mn><mrow><mo>+</mo><mo>+</mo></mrow></msup></math> resonances. This work demonstrates the efficacy of operators with covariant derivatives for studying excited hadrons.

Shuang-Hong Li

Wei-Yang Lai

Hong-Ying Jin

Probing excited <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>q</mi><mover accent="true"><mi>q</mi><mo stretchy="false">¯</mo></mover></math> mesons via QCD sum rules

We develop a framework for testing quantum gravity through the stochastic gravitational-wave background produced by evaporating near-Planck-mass primordial black holes. Because gravitons freestream from the emission region without rescattering, they preserve a direct spectral record of the black-hole temperature–mass relation <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>T</mi><mo stretchy="false">(</mo><mi>M</mi><mo stretchy="false">)</mo></math>, a relation that is erased for all other Hawking-radiated species by rapid thermalization. We translate six representative phenomenological beyond-semiclassical frameworks (the generalized uncertainty principle, loop quantum gravity, noncommutative geometry, asymptotic safety, string/Hagedorn physics, and tunneling backreaction) into distinct <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>T</mi><mo stretchy="false">(</mo><mi>M</mi><mo stretchy="false">)</mo></math> parameterizations and compute the resulting gravitational-wave spectra numerically within a hybrid semiclassical-phenomenological framework. Modifications that suppress <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>T</mi><mo stretchy="false">(</mo><mi>M</mi><mo stretchy="false">)</mo></mrow></math> shift the spectral peak by up to 10 decades in frequency, in some cases into the sensitivity bands of next-generation interferometers or resonant-cavity detectors, while models imposing a hard evaporation cutoff produce distinctive peak morphologies that distinguish between phenomenological classes of modified evaporation. We further discuss the impact of different choices for post-inflationary conditions in the very early Universe and note that breaking the remaining cosmological degeneracies and connecting these signatures to specific quantum-gravity theories requires complementary observables. We find that the relative spectral displacement between the standard Hawking prediction and any modified model is cosmology-independent, and hence spectral shape rather than absolute peak frequency provides the cleanest probe of Planck-scale physics.

Stefano Profumo

Probing Planck-scale physics with high-frequency gravitational waves