We use supersymmetric localization for 3d $$ \mathcal{N} $$ = 2 SCFTs to establish a relation of the form $$ {Z}_{S^1\times {S}^2}\sim {\left|{Z}_{S_b^3}\right|}^2 $$ between the superconformal index and the squashed three-sphere partition function. This applies to general 3d $$ \mathcal{N} $$ = 2 SCFTs and is derived using a saddle point approximation in the Cardy-like limit of small $\textit{S}$ radius and large squashing parameter. We also show a similar relation between the topologically twisted index and the squashed sphere partition function. In the context of holography our results lead to a relation between the partition function of supersymmetric asymptotically AdS black holes and the large $\textit{N}$ limit of $$ {Z}_{S_b^3} $$ of the dual SCFT. Since the latter encodes the gauged supergravity prepotential, this result is akin to the OSV conjecture for asymptotically flat black holes. We confirm this relation in detail for SCFTs arising from M2-branes using recent large $\textit{N}$ results from supersymmetric localization. We also briefly discuss a similar relation for 5d SCFTs and its implications for asymptotically AdS black holes.

Belgium

Nikolay Bobev

Japan

Sunjin Choi

South Korea

Junho Hong

France

Valentin Reys

Towards OSV in AdS

We investigate holographic spectral functions for general Sasaki-Einstein 5-manifolds dual to four-dimensional superconformal field theories, including supersymmetric indices, supersymmetric zeta functions, and supersymmetric determinants. The analytic structure of the supersymmetric zeta function, particularly its residue and special value, allows for the computation of the curvature-squared integral of the Sasaki-Einstein manifold and the subleading holographic anomaly. The reach of this spectral framework is not restricted to toric geometries and accommodates non-toric Sasaki-Einstein manifolds. For toric Sasaki-Einstein manifolds, we develop a combinatorial method to compute the holographic spectral functions and the holographic geometric invariants directly from the toric data.

Yu Nakayama

China

Tadashi Okazaki

Holographic spectral functions for Sasaki-Einstein 5-manifolds

Carrollian amplitudes are scattering amplitudes of massless particles written in position space at null infinity. We study various aspects of Carrollian amplitudes for gauge theory and gravity at loop level using primarily the modified Mellin prescription. Finite one-loop four-point Carrollian amplitudes in gauge theory are shown to maintain an analytic structure similar to tree level results. We compute the one-loop four-point Carrollian MHV amplitudes in planar 𝒩 = 4 super Yang-Mills theory, which are expressed as differential operators acting on tree level Carrollian amplitudes. This result is generalized to all loop orders using the Bern-Dixon-Smirnov (BDS) formula. Similar structures are observed at one-loop for Carrollian MHV amplitudes in 𝒩 = 8 supergravity. We next consider 2 → 2 scattering of massless scalars via gravitational interactions in the eikonal regime and show that the corresponding Carrollian amplitudes exhibit logarithmic behavior in the ‘Carroll time’ $\textit{u}$. We compute the discontinuities of these Carrollian amplitudes up to 𝒪($\textit{G}$ ) and show that they are descendants of Carrollian Born amplitudes. We observe similar logarithmic behavior in Carrollian amplitudes associated with the one-loop scalar box diagram. The dependence of this amplitude on dual scaling dimensions also differs from standard tree level results. Finally, we further study the infrared (IR) divergences of Carrollian amplitudes in massless scalar QED, gravity, and Yang-Mills theory. We show that Carrollian amplitudes in these theories naturally factorize, allowing us to provide an IR-safe definition for these objects.

United Kingdom

Vijay Nenmeli

Bin Zhu

On Carrollian loop amplitudes for gauge theory and gravity

The all-sky very-high-energy (10 − 10 GeV) atmospheric muon flux measured by IceCube shows a spectral hardening at the highest energies, indicating the presence of a prompt component. IceCube has also measured the atmospheric muon neutrino flux at high energy. However, since this flux is dominated by astrophysical neutrinos, only an upper bound can be placed on the prompt atmospheric $${\nu}_{\mu }+{\overline{\nu }}_{\mu }$$ contribution. In this work, we provide a new evaluation of the prompt atmospheric muon flux including an intrinsic charm component in the cosmic ray-air interactions. The latter enhances the forward production of $${\overline{D} }^{0}$$ , $\textit{D}$ , and Λ , which subsequently decay into final states containing muons and muon neutrinos. We show how the increase in the prompt muon flux due to intrinsic charm is accompanied by a corresponding enhancement in the prompt muon neutrino flux. We implement different intrinsic charm production models in MCEq to calculate the resulting lepton fluxes. We discuss the challenges of achieving predictions that are simultaneously consistent with both IceCube’s high-energy atmospheric muon flux measurements and IceCube upper bounds on the prompt muon neutrino flux, and we quantify the resulting discrepancies. As possible solutions, we explore scaling of the unflavored meson contributions to the prompt atmospheric muon flux to assess how such adjustments can reconcile these differences. The tensions emphasized in our work call for a refinement of the hadronic interaction models, especially the production of unflavored mesons, and for new experimental data sensitive to unflavored meson and heavy flavor production with reliable estimates of the associated uncertainties. We suggest that the energy and zenith angle dependence of muon and neutrino flux ratios from future neutrino telescope measurements may help to disentangle different scenarios.

United States

Laksha Das

Diksha Garg

Germany

Maria Garzelli

Mary Reno

Günter Sigl

The role of charm and unflavored mesons in prompt atmospheric lepton fluxes

$\textit{B}$ mesogenesis offers an interesting mechanism to generate the baryon asymmetry of the universe by converting the CP violation of the Standard Model into a net baryon number asymmetry. In this work we extend the $\textit{B}$ mesogenesis framework by incorporating all relevant $\textit{B}$ meson channels active after low-temperature reheating. We first revisit neutral $\textit{B}$ mesogenesis, providing the time-dependent decay rates including electron scattering. We then perform a systematic study of $\textit{B}$ decays, which are basically unexplored. We provide branching-ratio predictions using both leading-order factorization and a data-driven approach inspired by $\textit{D}$ → $\textit{M}$ $\textit{M}$ decays. These estimates allow us to quantify two $\textit{B}$ sources of mesogenesis: the previously discussed $${B}_{c}^{+}\to {B}^{+}{M}^{0}$$ channel and a new mechanism introduced in this work, $${B}_{c}^{+}\to {B}_{q}^{0}M$$ , in which the asymmetry is generated by combining direct CP violation with neutral-meson oscillations. Interestingly, in these channels the charm quark decays. Therefore, these decays give access to $\textit{charm CP violation}$ in modes with percent level branching ratios. With moderate assumptions, we find that $\textit{B}$ mesogenesis can match or exceed the neutral contribution depending on the semileptonic asymmetry and reheating temperature. Finally, we combine all three mechanisms and explore their viability in terms of the direct CP asymmetry, neutral-meson mixing parameters, early-universe fragmentation fractions and reheating temperature. We find that successful $\textit{B}$ mesogenesis requires an enhancement in the fragmentation fraction and semileptonic asymmetry of $${B}_{s}^{0}$$ at low reheating temperatures. For higher reheating temperatures, $\textit{B}$ mesogenesis dominates and can explain the baryon asymmetry with fragmentation fraction and direct CP asymmetry of $\textit{B}$ mesons at the percent level. Future measurements of $\textit{B}$ modes are thus highly anticipated to further probe the viability of unified $\textit{B}$ mesogenesis.

Netherlands

M. Burgos Marcos

A. Verheyden

K. Vos

From $\textit{B}$ $\textit{c}$ mesons to the baryon asymmetry: a unified $\textit{B}$ mesogenesis framework

Using the worldline in-in effective action obtained in [1], we derive the total even-in-velocity $\textit{relative}$ impulse, scattering angle, and time delay at fifth post-Newtonian (5PN) order, including radiation-reaction and hereditary contributions at ($\textit{G}$ $\textit{ν}$ ) and 𝒪($\textit{G}$ $\textit{ν}$ ). We introduce an isotropic-like description which, together with the associated losses of energy and angular momentum, fixes the evolution of the system entirely from scattering data. This framework opens the door to an unambiguous characterization of the underlying two-body dynamics solely in terms of scattering observables. Following [1], we isolate a $\textit{conservative}$ component using Feynman’s $\textit{i}$0 prescription. This sector contains both “tail-like” and “memory-like” contributions, the latter being intrinsically nonlocal in time and described by a double Principal-Value integral. Owing to the local-in-time character of the corresponding (in-in) action, we establish a systematic procedure that is consistent with Feynman’s prescription while preserving the complete local dynamics. This provides a universal contribution to the conservative (isotropic) Hamiltonian at 5PN order and, as a byproduct, also fixes the value of the Effective One Body coefficients $$\left\{{\overline{d} }_{5loc},{a}_{6loc}\right\}$$ consistently with the $\textit{Tutti-Frutti}$ framework. For completeness, we analyse the “$\textit{γ}$-3” prescription introduced in recent post-Minkowskian computations. When implemented in our formalism, we find exact agreement over the overlapping regime of validity. In contrast, Feynman’s prescription yields a (local) memory-like contribution with the $\textit{opposite}$ sign at ($\textit{G}$ $\textit{ν}$ ). We also find that an analogous $\textit{γ}$-3 rerouting at ($\textit{G}$ $\textit{ν}$ ) would be incompatible with the conjecture that all $\textit{π}$ terms arise solely from the potential region, while Feynman’s formulation preserves this expectation.

Rafael Porto

Massimiliano Riva

Black hole dynamics at fifth post-Newtonian order

We use effective field theory to factorize production matrix elements that appear in quarkonium cross sections in NRQCD. By applying a Hubbard-Stratonovich transformation we show that the soft and ultrasoft sectors of NRQCD can be decoupled from the heavy quark and antiquark fields in a hybrid vNRQCD/pNRQCD Lagrangian at leading order in the velocity power counting. This enables us to separate quarkonium production matrix elements in terms of matrix elements of color-singlet composite fields, which we can write as the wavefunction at the origin, and state independent vacuum correlators of chromo-electric and chromo-magnetic gluon fields. This approach verifies powerful connections between the LDMEs of different S-wave vector quarkonium states, originally derived using pNRQCD. Additionally, we find new operator contributions for the color-octet P-wave mechanism, which satisfy a similar set of relationships. Finally, this approach allows us to factorize the production matrix elements that appear in the transverse momentum dependent factorization framework, known as TMD soft transition functions, in terms of state independent gluon correlators. This work restores some universality for TMD production operators and dramatically improves the predictive power of NRQCD in the TMD framework.

Marston Copeland

Ivan Vitev

Factorizing quarkonium production matrix elements using effective field theory

We present the first calculation of the next-to-leading-order electroweak corrections to vector-boson scattering into doubly polarised Z bosons at the LHC in the fully leptonic decay channel. The production and decay of the two polarised Z bosons are consistently modelled in the double-pole approximation, separating polarisation states at the amplitude level and including factorisable real and virtual electroweak corrections. Doubly polarised and unpolarised signals are investigated and confronted with off-shell results. A broad analysis, including results at integrated and differential level, is carried out in a realistic, CMS-inspired fiducial setup. Our study paves the way to upcoming analyses with LHC Run-3 and High-Luminosity data as well as to further phenomenological investigations.

Ansgar Denner

Robert Franken

Santiago Chavez

Italy

Daniele Lombardi

Giovanni Pelliccioli

The cleanest of them all: NLO electroweak corrections to vector-boson scattering into doubly polarised ZZ pairs at the LHC

The difference between the charged and neutral pion masses can be predicted from a well-known dispersion relation involving a weighted integral of the vector-minus-axial spectral function over all energies. This relation, however, holds only in the chiral limit, while phenomenological applications involve physical light-quark masses and spectral input known only up to a finite scale. Here we combine dispersion theory, the operator product expansion and chiral perturbation theory with dynamical photons to determine the form of the corresponding physical finite-energy sum rule, including all corrections linear in the light-quark masses. We test this generalized relation using hadronic tau-decay data.

Sweden

J. Bijnens

N. Hermansson-Truedsson

Spain

A. Rodríguez-Sánchez

Pion mass-difference sum rules beyond the chiral limit

Bi-spinor and G-structure methods are used to classify the possible consistent truncations of type II supergravity to $\textit{d}$ = 6 Einstein-Maxwell (gauged) supergravity, and its consistent sub-sectors. In the absence of R-symmetry gauging and a tensor multiplet we establish that every supersymmetric Mink solution defines an embedding of the $\textit{d}$ = 6 theory. Adding a tensor multiplet places restrictions on these embeddings, but embeddings still exist. In the presence of R-symmetry gauging the internal spaces of the embeddings are neither related to Mink or AdS . Under the assumption that the internal space contains a single U(1) isometry housing the $\textit{d}$ = 6 gauge field we classify the possible embedding manifolds. We find two classes of embedding for the entire theory, one of which is governed by a Toda-like equation and contains at least one prototype bounded embedding, albeit containing likely un-physical singularities. In the absence of a tensor multiple the classes of embeddings become more permissive, though the PDEs governing them become more complicated in general.

Niall Macpherson

Ricardo Stuardo

Type II embeddings for $\textit{d}$ = 6 Einstein-Maxwell gauged supergravity