PaperPanorama

HEP Phenomenology·hep-ph

Thu·Nov 30, 2023

45 papers29 primary·16 cross-listed·reconstructed*

  1. 01*

    Probing nuclear properties and neutrino physics with current and future CE{\nu}NS experiments

    R. R. Rossi🇧🇷 · G. Sanchez Garcia🇪🇸 · M. Tórtola🇪🇸

    The recent observation of Coherent Elastic Neutrino Nucleus Scattering (CE{\nu}NS) with neutrinos from pion decay at rest ({\pi}-DAR) sources by the COHERENT Collaboration has raised interest in this process in the search for new physics. Unfortunately, current uncertainties in the determination of nuclear parameters relevant to those processes can hide new physics effects. This is not the case for processes involving lower-energy neutrino sources such as nuclear reactors. Note, however, that a CE{\nu}NS measurement with reactor neutrinos depends largely on the determination of the quenching factor, making its observation more challenging. In the upcoming years, once this signal is confirmed, a combined analysis of {\pi}-DAR and reactor CE{\nu}NS experiments will be very useful to probe particle and nuclear physics, with a reduced dependence on the nuclear uncertainties. In this work, we explore this idea by simultaneously testing the sensitivity of current and future CE{\nu}NS experiments to neutrino non-standard interactions (NSI) and the neutron root mean square (rms) radius, considering different neutrino sources as well as several detection materials. We show how the interplay between future reactor and accelerator CE{\nu}NS experiments can help to get robust constraints on the neutron rms, and to break degeneracies between the NSI parameters. Our forecast could be used as a guide to optimize the experimental sensitivity to the parameters under study.

    hep-phPRD(2024)·8 citations
  2. 02*

    Third-generation-philic Hidden Naturalness

    Yi Chung🇩🇪 · Florian Goertz🇩🇪

    We present a solution to the electroweak hierarchy problem, where the relevant new particles are third-generation-philic and hidden in SM processes with third-generation fermions. Due to this feature, the mass bounds from direct searches are much weaker and the required fine-tuning can be reduced drastically. A concrete model is constructed based on a fundamental composite Higgs model with collective symmetry breaking and extended hypercolor mechanism. The construction allows to raise the scale to TeV, corresponding to resonances at TeV, without much tuning - employing ingredients that are naturally inherent in the (composite) Goldstone-Higgs framework. The experimental signatures are discussed in detail. It is found that current bounds allow for a model with negligible tuning.

    hep-phPRD(2024)·9 citations
  3. 03*

    Kicking it Off(-shell) with Direct Diffusion

    Anja Butter🇫🇷 · Tomas Jezo🇩🇪 · Michael Klasen🇩🇪 · Mathias Kuschick🇩🇪 · Sofia Palacios Schweitzer🇩🇪 · Tilman Plehn🇩🇪

    Off-shell effects in large LHC backgrounds are crucial for precision predictions and, at the same time, challenging to simulate. We present a novel method to transform high-dimensional distributions based on a diffusion neural network and use it to generate a process with off-shell kinematics from the much simpler on-shell one. Applied to a toy example of top pair production at LO we show how our method generates off-shell configurations fast and precisely, while reproducing even challenging on-shell features.

    hep-phSciPost Phys.Core(2024)·36 citations
  4. 04*

    Dynamical origin of Type-I Seesaw with large mixing

    Yi Chung🇩🇪

    We investigate Type-I Seesaw models where the right-handed neutrino masses are dynamically generated by strong interactions. Using horizontal gauge symmetry as the source of strong dynamics, a nontrivial flavor structure can also be introduced dynamically. We find that the right-handed neutrino mass matrix with a strongly anti-diagonal structure emerges when the three right-handed neutrinos are in the triplet representation of horizontal gauge symmetry. With an assumption of a Dirac neutrino mass matrix with hierarchical eigenvalues and small mixing angles, analogous to the up-type quark sector, and certain substructures, the resulting light neutrino mass matrix from the type-I seesaw mechanism can accommodate the large mixing and weak hierarchy observed in low-energy neutrino data. The neutrino puzzles can, therefore, be understood as the consequence of strong horizontal gauge interactions. We also discuss the potential UV completion and the phenomenology that could be tested in the future.

    hep-ph2 citations
  5. 05*

    TorchAmi: Generalized CPU/GPU Implementation of Algorithmic Matsubara Integration

    M. D. Burke🇨🇦 · J. P. F. LeBlanc🇨🇦

    We present torchami, an advanced implementation of algorithmic Matsubara integration (AMI) that utilizes pytorch as a backend to provide easy parallelization and GPU support. AMI is a tool for analytically resolving the sequence of nested Matsubara integrals that arise in virtually all Feynman perturbative expansions. In this implementation we present a new AMI algorithm that creates a more natural symbolic representation of the Feynman integrands. In addition, we include peripheral tools that allow for import and labelling of simple graph structures and conversion to torchami input. The code is written in c++ with python bindings provided.

    hep-phcond-mat.otherphysics.comp-phComput.Phys.Commun.(2025)·4 citations
  6. 06*

    Exploring the Electromagnetically Interacting Dark Matter at the International Linear Collider

    Manish Kumar Sharma🇮🇳 · Saumyen Kundu🇮🇳 · Prasanta Kumar Das🇮🇳

    Dark Matter being electrically neutral does not participate in electromagnetic interactions at leading order. However, we discuss here fermionic dark matter (DM) with permanent magnetic and electric dipole moment that interacts electromagnetically with photon at loop-level through a dimension-5 operator. We discuss the search prospect of the dark matter at the proposed International Linear Collider (ILC) and constrain the parameter space in the plane of the DM mass and the cutoff scale . At the 500 GeV ILC with ab of integrated luminosity we probed the mono-photon channel and utilizing the advantages of beam polarization we obtained an upper bound on the cutoff scale that reaches up to TeV.

    hep-ph2 citations
  7. 07*

    The Principle of Maximum Conformality Correctly Resolves the Renormalization-Scheme-Dependence Problem

    Jiang Yan · Stanley J. Brodsky · Leonardo Di Giustino · Philip G. Ratcliffe · Sheng-Quan Wang · Xing-Gang Wu

    In this paper, we clarify a serious misinterpretation and consequent misuse of the Principle of Maximum Conformality (PMC), which also can be served as a mini review of PMC. We emphasize that the purpose of the PMC is to achieve precise fixed-order pQCD predictions, free from conventional renormalization scheme and scale ambiguities. We demonstrate that the PMC predictions satisfy all of the self-consistency conditions of the renormalization group and standard renormalization-group invariance; the PMC predictions are thus independent of any initial choice of renormalization scheme and scale. The scheme independence of the PMC is also ensured by commensurate scale relations which relate different observables to each other. Moreover, in the Abelian limit, the PMC dovetails into the well-known Gell-Mann--Low framework, a method universally revered for its precision in QED calculations. Due to the elimination of factorially-divergent renormalon terms, the PMC series not only attains a convergence behavior far superior to that of its conventional counterparts but also deftly curtails any residual scale dependence caused by the unknown higher-order terms. This refined convergence, coupled with its robust suppression of residual uncertainties, furnishes a sound and reliable foundation for estimating the contributions from unknown higher-order terms. Anchored in the bedrock of standard renormalization group invariance, the PMC simultaneously eradicates the factorial divergences and eliminates superfluous systematic errors, which inversely provides a good foundation for achieving high-precision pQCD predictions. Consequently, owing to its rigorous theoretical underpinnings, the PMC is eminently applicable to virtually all high-energy hadronic processes.

    hep-phhep-thSymmetry(2025)·8 citations
  8. 08*

    Axion minicluster streams in the solar neighbourhood

    Ciaran A. J. O'Hare🇦🇺 · Giovanni Pierobon🇦🇺 · Javier Redondo🇪🇸

    A consequence of QCD axion dark matter being born after inflation is the emergence of small-scale substructures known as miniclusters. Although miniclusters merge to form minihalos, this intrinsic granularity is expected to remain imprinted on small scales in our galaxy, leading to potentially damaging consequences for the campaign to detect axions directly on Earth. This picture, however, is modified when one takes into account the fact that encounters with stars will tidally strip mass from the miniclusters, creating pc-long tidal streams that act to refill the dark matter distribution. Here we ask whether or not this stripping rescues experimental prospects from the worst-case scenario in which the majority of axions remain bound up in unobservably small miniclusters. We find that the density sampled by terrestrial experiment on mpc-scales will be, on average, around 70--90\% of the average local DM density, and at a typical point in the solar neighbourhood, we expect most of the dark matter to be comprised of debris from -- overlapping streams. If haloscopes can measure the axion signal with high-enough frequency resolution, then these streams are revealed in the form of an intrinsically spiky lineshape, in stark contrast with the standard assumption of a smooth, featureless Maxwellian distribution -- a unique prediction that constitutes a way for experiments to distinguish between pre and post-inflationary axion cosmologies.

    hep-phastro-ph.COPRL(2024)·32 citations
  9. 09*

    Electroweak Strings in the Standard Model

    Liping Zou🇨🇳 · Pengming Zhang🇨🇳 · Yongmin Cho🇰🇷

    We argue that the existence of the electroweak monopole predicts the existence of the electroweak string in the standard model made of monopole-antimonopole pair separated infinitely apart, which carry the quantized magnetic flux . We show how to construct such quantized magnetic flux string solution. Our result strongly indicates that genuine fundamental electromagnetic string could exist in nature which could actually be detected. We discuss the physical implications of our result in cosmology.

    hep-phEPJC(2024)·1 citation
  10. 10*

    Probing entanglement and testing Bell inequality violation with at Belle II

    Karl Ehatäht🇪🇪 · Marco Fabbrichesi🇮🇹 · Luca Marzola🇪🇪 · Christian Veelken🇪🇪

    We present a feasibility study to probe quantum entanglement and Belle inequality violation in the process at a center-of-mass energy of GeV. The sensitivity of the analysis is enhanced by applying a selection on the scattering angle in the center-of-mass frame. We analyze events in which both leptons decay to hadrons, using a combination of decay channels , , and . The spin orientation of the leptons in these decays is reconstructed using the polarimeter-vector method. Assuming a dataset of million events and accounting for experimental resolutions, we expect the observation of quantum entanglement and Bell inequality violation by the Belle-II experiment will be possible with a significance well in excess of five standard deviations.

    hep-phhep-exquant-phPRD(2024)·93 citations
  11. 11*

    Dependence of the structure of the elastic scattering amplitude on Mandelstam variables at high energies

    O.V. Selyugin🇷🇺

    Analysis of new experimental data obtained by the TOTEM and ATLAS Collaborations at the LHC together with old data obtained at the SPS and Tevatron colliders at small momentum transferin the framework of the high energy generalized structure (HEGS) model allows one to determine the dependence of different parts of the hadron elastic scattering amplitude on the mandelstam kinematic variables the and

    hep-phPhys.Part.Nucl.(2024)·0 citations
  12. 12*

    Illuminating the impact-parameter dependence of UPC dijet photoproduction

    Kari J. Eskola🇫🇮 · Vadim Guzey🇫🇮 · Ilkka Helenius🇫🇮 · Petja Paakkinen🇫🇮 · Hannu Paukkunen🇫🇮

    We present new NLO pQCD predictions for photoproduction of dijets in ultraperipheral PbPb collisions at 5.02 TeV with a realistic photon flux and up-to-date nuclear PDFs. Our calculation of the impact parameter dependence of the photon flux includes the effects of the nuclear form factor in the photon-emitting nucleus and the spatial dependence of nuclear PDFs of the target nucleus, which are estimated using the Wood-Saxon nuclear density profile. We show that a significant portion of the measured dijets at large originate from events with impact parameters of the order of a few nuclear radii, and that the cross section predictions therefore become sensitive to the modelling of the nuclear geometry and photon flux close to the source nucleus.

    hep-phEPJ Web Conf.(2024)·1 citation
  13. 13*

    Multiple soft-photon emission at next-to-leading power to all orders

    Tim Engel🇩🇪

    This paper derives a next-to-leading power (NLP) soft theorem for multi-photon emission to all orders in the electromagnetic coupling constant, generalising the leading-power theorem of Yennie, Frautschi, and Suura. Working in the QED version of heavy-quark effective theory, multi-emission amplitudes are shown to reduce to single- and double-radiation contributions only. Single soft-photon emission, in turn, is described by the recent all-order extension of the Low-Burnett-Kroll theorem, where the tree-level formula is supplemented with a one-loop exact soft function. The same approach is used in this article to prove that the genuine double-emission contribution is tree-level exact. As a validation and a first non-trivial application of the multi-photon theorem, the real-real-virtual electron-line corrections to muon-electron scattering are calculated at NLP in the soft limit.

    hep-phhep-thJHEP(2024)·14 citations
  14. 14*

    Ellipticity of dilepton production from a hot and magnetized hadronic medium

    Rajkumar Mondal🇮🇳 · Nilanjan Chaudhuri🇮🇳 · Snigdha Ghosh🇮🇳 · Sourav Sarkar🇮🇳 · Pradip Roy🇮🇳

    We study the azimuthal angle and transverse momentum dependence of dilepton production from hot and magnetized hadronic matter using -meson dominance. The thermomagnetic spectral function of the is evaluated using the real time method of thermal field theory and Schwinger proper-time formulation. A continuous spectrum is obtained in which there is sizeable Landau cut contributions in the low invariant mass region as a consequence of finite background field. The emission rate of the dileptons is found to be significantly anisotropic in this region and the later effectively increases with the strength of the background field. In addition, we also evaluate the elliptic flow parameter () as a function of invariant mass for different values of magnetic field and temperature. We find that in low invariant mass region remains positive at lower values of signifying that the production rate could be larger along the direction transverse to the background field. This behaviour is consistent with the angular dependence of dilepton production rate.

    hep-phnucl-thEPJA(2023)·7 citations
  15. 15*

    Quark matter with an anisotropic momentum distribution

    Wei-bo He🇨🇳 · Guo-yun Shao🇨🇳

    Motivated by the anisotropic momentum distribution of particles in heavy-ion collisions, we study the angular dependence of quark average momentum and quark distribution function in the Polyakov-Nambu--Jona-Lasinio (PNJL) quark model. We also investigate the phase transitions and net baryon number fluctuations in anisotropic quark matter. The numerical results suggest that the QCD phase structure and isentropic trajectories are sensitive to the anisotropic parameter at finite density, in particular, in the area near the critical region and the first-order phase transition. Compared with the isotropic quark matter, the values of baryon number kurtosis and skewness at lower collision energies are possibly enhanced with the anisotropic momentum distribution squeezed along the direction of nucleus-nucleus collision in experiments.

    hep-phPRD(2023)·2 citations
  16. 16*

    Phenomenological analysis of the quasi-two-body decays in PQCD Approach

    Wen-Sheng Fang🇨🇳 · Zhi-Tian Zou🇨🇳 · Ying Li🇨🇳

    The quasi-two-body decays are calculated in PQCD approach based on the factorization by introducing the wave functions of pair associated with the resonances , and . The results show that most branching fractions are at the order of or even smaller. However, for decays enhanced by the CKM element , their branching fractions are at the order of , which are measurable in the current ongoing experiments. Based on the narrow-width-approximation we also extract the branching fractions of the corresponding two-body decays and the results are in good agreement with previous predictions. Because these decays are only governed by the tree operators, there are no asymmetries in these decays in the standard model.

    hep-phPRD(2023)·5 citations
  17. 17*

    Cosmological perturbations from five-dimensional inflation

    Ignatios Antoniadis🇫🇷 · Jules Cunat🇫🇷 · Anthony Guillen🇫🇷

    It was recently proposed that five-dimensional inflation can relate the causal size of the observable universe to the present weakness of gravitational interactions by blowing up an extra compact dimension from the microscopic fundamental length of gravity to a large size in the micron range, as required in the Dark Dimension proposal. Here, we compute the power spectrum of all primordial fluctuations emerging from a 5-dimensional inflaton in a slow-roll region of its potential, showing an interesting change of behaviour at large scales corresponding to angles larger than about 10 degrees in the sky.

    hep-phastro-ph.COhep-thJHEP(2024)·20 citations
  18. 18*

    A neutrino floor for the Migdal effect

    Gonzalo Herrera🇩🇪

    Neutrino-nucleus scatterings in the detector could induce electron ionization signatures due to the Migdal effect. We derive prospects for a future detection of the Migdal effect via coherent elastic solar neutrino-nucleus scatterings in liquid xenon detectors, and discuss the irreducible background that it constitutes for the Migdal effect caused by light dark matter-nucleus scatterings. Furthermore, we explore the ionization signal induced by some neutrino electromagnetic and non-standard interactions on nuclei. In certain scenarios, we find a distinct peak on the ionization spectrum of xenon around 0.1 keV, in clear contrast to the Standard Model expectation.

    hep-phhep-exJHEP(2024)·38 citations
  19. 19*

    Molecular-type pentaquarks predicted by an extended hidden gauge symmetry approach

    Zhong-Yu Wang🇨🇳 · Chu-Wen Xiao🇨🇳 · Zhi-Feng Sun🇨🇳 · Xiang Liu🇨🇳

    In this work, we investigate the double-heavy molecular pentaquark states with the quark contents , , and by using the coupled channel approach. The extended local hidden gauge Lagrangians are used to obtain the meson-baryon interactions by exchanging the vector mesons. We predict some candidates for the molecular states with the quantum numbers , whose binding energies are of the order of MeV and whose widths are all less than MeV. These predicted exotic double-heavy molecular pentaquark states may be accessible in future experiments such as LHCb.

    hep-phPRD(2024)·11 citations
  20. 20*

    Charged Hadron Fragmentation Functions at High Energy Colliders

    Ignacio Borsa🇩🇪 · Daniel de Florian🇦🇷 · Rodolfo Sassot🇦🇷 · Marco Stratmann🇩🇪

    We update our extraction of parton-to-charged hadron fragmentation functions at next-to-leading order accuracy in QCD, focusing on the wealth of data collected at the Large Hadron Collider over the past decade. We obtain an accurate description of single-inclusive processes involving unidentified charged hadrons produced at different rapidities and transverse momenta in proton-proton collisions in a wide range of center-of-mass system energies between 0.9 and 13 TeV, along with measurements performed in proton-antiproton collisions at the Tevatron Collider in the past. NLO estimates of charged hadron production rates agree best with data when the theoretical factorization scales are selected similar to those optimized for identified pions, kaons, and protons in a recent global QCD analysis.

    hep-phPRD(2024)·12 citations
  21. 21*

    Constraining Gamma-ray Lines from Dark Matter Annihilation using Fermi-LAT and H.E.S.S. data

    Lucia Angel🇧🇷 · Guillermo Gambini🇧🇷 · Leticia Guedes🇧🇷 · Farinaldo S. Queiroz🇧🇷 · Vitor de Souza🇧🇷

    Using 14 years of Fermi-LAT data and 10 years of H.E.S.S. observations in the direction of the galactic center, we derive limits on gamma-ray lines originated from dark matter annihilations for fermionic and scalar fields. We describe the dark matter annihilation into or final states in terms of effective operators and place limits on the energy scale as a function of the dark matter mass taking into account the energy resolution of the instruments. For the Fermi-LAT data, we considered an NFW and a contracted NFW dark matter density profile, the latter being preferred by the Fermi GeV excess. For the H.E.S.S. observation, we used an NFW and Einasto profile. Fermi-LAT yields the most stringent constraints for dark matter masses below 300 GeV, whereas H.E.S.S. has the strongest ones for dark matter masses above 1 TeV. The telescopes share similar sensitivities for dark matter masses between 300 GeV and 1 TeV. We conclude that Fermi-LAT (H.E.S.S.) can probe energy scales up to ~TeV for scalar and fermionic dark matter particles.

    hep-phJCAP(2024)·4 citations
  22. 22*

    Heavy vector-like quarks decaying to exotic scalars: a case study with triplets

    Avik Banerjee🇸🇪 · Venugopal Ellajosyula🇸🇪 · Luca Panizzi🇮🇹

    We investigate the pair production of a vector-like quark triplet with hypercharge 5/3 decaying into top quark and a complex scalar triplet with hypercharge 1 at the LHC. This novel scenario, featuring particles with exotic charges - two quarks with charge 8/3 and 5/3 and a scalar with charge 2 - serves as a unique window to models based on the framework of partial compositeness, where these particles naturally emerge as bound states around the TeV scale. Leveraging on the LHC data we establish exclusion limits on the masses of the vector-like quark and the scalar triplet. Subsequently, we design an analysis strategy aimed at improving sensitivity in the region which is still allowed. Our analysis focuses on two specific regions in the parameter space: the first entails a large mass gap between the vector-like quarks and the scalars, so that the vector-like quarks can decay into the scalars; the second involves a small mass gap, such that this decay is forbidden. To simplify the parameter space, both vector-like quarks and scalars are assumed to be degenerate or almost degenerate within the triplets, such that chain decays between fermions and scalars are suppressed. As a result, we found that final states characterized by a same-sign lepton pair, multiple jets, and high net transverse momentum (i.e. effective mass) will play a pivotal role to unveil this model and, more in general, models characterised by multiple vector-like quarks around the same mass scale during the high luminosity LHC phase.

    hep-phhep-exJHEP(2024)·18 citations
  23. 23*

    Baryon Transport in Color Flux Tubes

    Scott Pratt🇺🇸

    Color flux tubes are a standard perspective from which to understand stopping in high-energy collisions. Mechanisms for baryon transport and polarization within a tube are considered here, both in regards to the the transport of baryons from the target and projectile toward mid-rapidity, and in regards to the correlations of baryon-antibaryon pairs created in the tube. The roles of tube merging and gluon radiation with a tube are emphasized.

    hep-phnucl-thPRC(2024)·5 citations
  24. 24*

    Angling for Insights: Illuminating Light New Physics at Mu3e through Angular Correlations

    Simon Knapen🇺🇸 · Kevin Langhoff🇺🇸 · Toby Opferkuch🇺🇸 · Diego Redigolo🇮🇹

    We examine the capability of Mu3e to probe light new physics scenarios that produce a prompt electron-positron resonance and demonstrate how angular observables are instrumental in enhancing the experimental sensitivity. We systematically investigate the effect of Mu3e's expected sensitivity on the parameter space of the dark photon, as well as on axion-like particles and light scalars with couplings to muons and electrons.

    hep-phJHEP(2024)·15 citations
  25. 25*

    A Robust Search for Lepton Flavour Violating Axions at Mu3e

    Simon Knapen🇺🇸 · Kevin Langhoff🇺🇸 · Toby Opferkuch🇺🇸 · Diego Redigolo🇮🇹

    We propose a search at Mu3e for lepton flavor violating axion(-like) particles in decays. By requiring an additional pair from internal conversion, one can circumvent the calibration challenges which plague the channel for axions lighter than 20 MeV. Crucially, the corresponding reduction in signal rate is to a large extent compensated for by Mu3e's ability to resolve highly collimated tracks. For phase I of Mu3e, we project a sensitivity to decay constants as high as GeV which probes uncharted parameter space in scenarios of axion dark matter. The sensitivity to axions which couple primarily to right-handed leptons can be further improved by leveraging the polarisation of the muon beam.

    hep-phJHEP(2025)·38 citations
  26. 26*

    Closing the dark photon window to thermal dark matter

    Leon M. G. de la Vega🇲🇽 · R. Ferro-Hernandez🇩🇪 · A. García-Viltres🇲🇽 · Eduardo Peinado🇲🇽 · E. Vázquez-Jáuregui🇲🇽

    The nature of dark matter remains a central question in particle physics, cosmology, and astrophysics. The prevailing hypothesis postulates that dark matter consists of particles that interact only weakly with Standard Model particles. However, the knowledge of dark matter properties beyond these interactions is limited. This study explores a scenario involving a dark photon as a mediator between dark matter and the Standard Model, akin to the photon's role in electromagnetism. Recent cosmological and experimental evidence impose constraints on this scenario, focusing on results from direct detection experiments such as PICO-60, XENON-1T, and PANDAX-4T. The results reveal severe constraints, effectively closing the window for laboratory searches for dark photons as mediators between the Standard Model and the dark sector (dark electrons) in the secluded dark matter scenario. The findings underscore the need for alternative explanations and offer fresh perspectives on the ongoing quest to understand dark matter and its interactions since they are nearly independent of the dark electron fraction content for the total dark matter. This analysis significantly narrows down the parameter space for thermal dark matter scenarios involving a dark photon portal, reinforcing the urgency of exploring alternative models and designing new experiments to unravel the mysteries surrounding the nature of dark matter.

    hep-phhep-exhep-th5 citations
  27. 27*

    Bounding the Dimension-5 Seesaw Portal with Non-Pointing Photon Searches

    L. Duarte🇺🇾 · J. Jones-Pérez🇵🇪 · C. Manrique-Chavil🇵🇪

    The addition of operators to the Seesaw model leads to the Dimension-5 Seesaw Portal. Here, two new operators provide interactions for the heavy sterile neutrinos. In particular, the Higgs boson can have a large branching ratio into two heavy neutrinos, meaning that these states can be searched for at the LHC. Moreover, the heavy neutrinos can now decay dominantly into light neutrinos and photons. If the heavy neutrinos are long-lived, then searches for delayed, non-pointing photons can constrain the model. In this work, we carry out a detailed recast of an ATLAS search for such displaced photons, triggered by a charged lepton produced in association to the Higgs, placing bounds on the branching ratio for Higgs decay into two heavy neutrinos as low as 2%.

    hep-phhep-exJHEP(2024)·23 citations
  28. 28*

    Constraining the Higgs Trilinear Coupling from an Quadruplet with Bounded-from-Below Conditions

    Kristjan Kannike🇪🇪

    Integrating out a heavy scalar can cause the Higgs trilinear coupling to deviate from its Standard Model value: a good example is provided by an quadruplet. Constraints on the full theory, however, can limit the size of the deviation. We show that the bounded-from-below conditions for the Standard Model extended by an quadruplet strongly constrain the -breaking Higgs portal and can bound the Higgs trilinear coupling close to its Standard Model value. For TeV-scale quadruplet masses in models with custodial symmetry violation, these constraints can be a few times stronger than constraints from electroweak precision measurements. For the custodial quadruplet, these are the strongest theoretical constraints available.

    hep-phJHEP(2024)·7 citations
  29. 29*

    A closer look at the explanation of the ATOMKI nuclear anomalies

    P. M. Ferreira🇵🇹 · B. L. Gonçalves🇵🇹 · F. R. Joaquim🇵🇹

    We revisit the gauged explanation of the ATOMKI nuclear anomalies, in which the new gauge boson is the hypothetical particle. It is known that the vanilla scenario is unable to account for appropriate couplings, namely the suppression of the couplings of to neutrinos, which motivates adding vector-like leptons. The simplest case, in which the new fields have charges equal to , is highly disfavoured since it requires large mixing with the Standard Model fields. One solution recently put forward is to consider large charges to counterbalance small mixing. We show that, in this scenario, and after taking into account several phenomenological constraints, the dominant contribution to the muon anomalous magnetic moment is expected to be extremely large and with a negative sign, being thus excluded by experiment.

    hep-phJHEP(2024)·3 citations
  30. 30*

    A model-independent tripartite test of cosmic distance relations

    Isabela Matos🇬🇧 · Miguel Quartin🇩🇪 · Luca Amendola🇩🇪 · Martin Kunz🇨🇭 · Riccardo Sturani🇧🇷

    Cosmological distances are fundamental observables in cosmology. The luminosity (), angular diameter () and gravitational wave () distances are all trivially related in General Relativity assuming no significant absorption of photons in the extragalactic medium, also known as cosmic opacity. Supernovae have long been the main cosmological standard candle, but bright standard sirens are now a proven alternative, with the advantage of not requiring calibration with other astrophysical sources. Moreover, they can also measure deviations from modified gravity through discrepancies between and . However, both gravitational and cosmological parameters are degenerate in the Hubble diagram, making it hard to properly detect beyond standard model physics. Finally, recently a model-independent method named FreePower was proposed to infer angular diameter distances from large-scale structure which is independent of the knowledge of both early universe and dark energy physics. In this paper we propose a tripartite test of the ratios of these three distances with minimal amount of assumptions regarding cosmology, the early universe, cosmic opacity and modified gravity. We proceed to forecast this test with a combination of LSST and Roman supernovae, Einstein Telescope bright sirens and a joint DESI-like + Euclid-like galaxy survey. We find that even in this very model-independent approach we will be able to detect, in each of many redshift bins, percent-level deviations in these ratios of distances, allowing for very precise consistency checks of CDM and standard physics. It can also result in sub-percent measurements of .

    astro-ph.COgr-qchep-phJCAP(2024)·17 citations
  31. 31*

    The four-gluon vertex in Landau gauge

    Manuel Colaço🇵🇹 · Orlando Oliveira🇵🇹 · Paulo J. Silva🇵🇹

    The Landau gauge four-gluon vertex is studied using high statistical lattice simulations for several momentum configurations. Furthermore, the outcome of the lattice QCD simulations is compared with calculations performed with continuum Schwinger-Dyson equations.

    hep-lathep-phPoS(2024)·4 citations
  32. 32*

    Amplifying the Chirp: Using Deep Learning (U-Nets) to filter signal from noise in LIGO data

    Akshay Ghalsasi🇺🇸

    The direct detection of gravitational waves by LIGO has heralded a new era for astronomy and physics. Typically the gravitational waves observed by LIGO are dominated by noise. In this work we use Deep Convolutional Neural Networks (specifically U-Nets) to filter a clean signal from noisy data. We present two realizations of U-Net filters, the Noise2Clean U-Net filter which is trained using noisy and clean realizations of the same signal, as well as Noise2Noise U-Net which is trained on two separate noisy realization of the same signal. We find that the U-Nets successfully filter signal from noise. We also benchmark the performance of U-Nets by using them to detect the binary presence or absence of gravitational wave signals in data.

    gr-qcastro-ph.COastro-ph.IMhep-ph2 citations
  33. 33*

    Fourier Neural Differential Equations for learning Quantum Field Theories

    Isaac Brant🇬🇧 · Alexander Norcliffe🇬🇧 · Pietro Liò🇬🇧

    A Quantum Field Theory is defined by its interaction Hamiltonian, and linked to experimental data by the scattering matrix. The scattering matrix is calculated as a perturbative series, and represented succinctly as a first order differential equation in time. Neural Differential Equations (NDEs) learn the time derivative of a residual network's hidden state, and have proven efficacy in learning differential equations with physical constraints. Hence using an NDE to learn particle scattering matrices presents a possible experiment-theory phenomenological connection. In this paper, NDE models are used to learn theory, Scalar-Yukawa theory and Scalar Quantum Electrodynamics. A new NDE architecture is also introduced, the Fourier Neural Differential Equation (FNDE), which combines NDE integration and Fourier network convolution. The FNDE model demonstrates better generalisability than the non-integrated equivalent FNO model. It is also shown that by training on scattering data, the interaction Hamiltonian of a theory can be extracted from network parameters.

    cs.LGhep-phquant-ph0 citations
  34. 34*

    Magnetic field simulations and measurements on the mini-ICAL detector

    Honey Khindri (HBNI, IMSc)🇮🇳 · B. Satyanarayana (TIFR)🇮🇳 · D. Indumathi (HBNI, IMSc)🇮🇳 · V.M. Datar (HBNI, IMSc)🇮🇳 · R. Shinde (TIFR)🇮🇳 · N. Dalal (BARC)🇮🇳 · S. Prabhakar (BARC)🇮🇳 · S. Ajith (BARC)🇮🇳

    The ICAL (Iron Calorimeter) is a 51 kTon magnetized detector proposed by the INO collaboration. It is designed to detect muons with energies in the 1-20 GeV range. A magnetic field of about 1.5 T in the ICAL detector will be generated by passing a DC current through suitable copper coils. This will enable it to distinguish between muons and anti-muons that will be generated from the interaction of atmospheric muon neutrinos and anti-neutrinos with iron. This will help in resolving the open question of mass ordering in the neutrino sector. Apart from charge identification, the magnetic field will be used to reconstruct the muon momentum (direction and magnitude). Therefore it is important to know the magnetic field in the detector as accurately as possible. We present here an (indirect) measurement of the magnetic field in the 85 ton prototype mini-ICAL detector working in Madurai, Tamil Nadu, for different coil currents. A detailed 3-D finite element simulation was done for the mini-ICAL geometry using Infolytica MagNet software and the magnetic field was computed for different coil currents. This paper presents, for the first time, a comparison of the magnetic field measured in the air gaps with the simulated magnetic field, to validate the simulation using real time data. Using the simulations the magnetic field inside the iron is estimated.

    hep-exhep-phJINST(2024)·2 citations
  35. 35*

    Generation of Isocurvature from Curvature Inhomogeneities on Super-Horizon Scales

    Albert Stebbins🇺🇸

    Here it is shown 1) how isocurvature inhomogeneities correlated on causally disconnected (super-horizon) scales are generated from curvature inhomogeneities which are known to be correlated on these scales 2) that super-horizon isocurvature generation is nearly inevitable for non-equilibrium chemical processes 3) that the amplitude of the compositional isocurvature correlations a) can be large for production of rare objects, b) falls off rapidly with separation c) falls off at scales below the horizon when these modes are generated. These two fall-offs results in an "isocurvature bump" in the power spectrum. Isocurvature generation is illustrated by the process of dark matter freeze-in, computed here with both separate universe modelling and linear perturbation theory. For freeze-in the most prominent isocurvature modes are inhomogeneities in the ratio of dark matter to standard model matter. Much smaller inhomogeneities in the ratio of baryons to standard model entropy are also produced. Previous constraints on freeze-in from Ly- clouds limit the bump enhancement to on comoving scales Mpc. Current observations are not sensitive to the isocurvature modes generated in viable freeze-in models. Results are obtained using a somewhat novel framework to describe cosmological inhomogeneities.

    astro-ph.COhep-ph6 citations
  36. 36*

    Study on Lambda(1405) in the flavor SU(3) limit in the HAL QCD method

    Kotaro Murakami🇯🇵 · Sinya Aoki🇯🇵

    We study interactions between the S-wave octet pseudo-scalar (PS) meson and octet baryon in the flavor SU(3) limit using the HAL QCD method at the PS meson mass . We focus on the singlet and two octet channels, where the poles corresponding to have been predicted in the chiral unitary model. For calculations with -baryon source operators with zero momentum, we employ the conventional stochastic calculation combined with the covariant-approximation averaging to calculate the all-to-all propagators. Due to a zero of the R-correlator (a kind of wave function), the leading order (LO) potential obtained by the single channel analysis has a singular point in all channels, which makes it difficult to obtain reliable binding energies. To overcome this problem, we take a linear combination of two octet R-correlators with a relative weight such that it does not cross zero, as two octet channels are suggested to couple to the same low-energy states with different weights. The potential calculated from such the linear combination shows strong attraction without singularities, though its shape depends on the relative weight. Our estimation for the binding energy in the octet channel is , which is consistent with 156(8) MeV estimated from the two-point correlation function within errors.

    hep-lathep-phnucl-thPoS(2024)·4 citations
  37. 37*

    Revisiting stochastic inflation with perturbation theory

    Gonzalo A. Palma🇨🇱 · Spyros Sypsas🇹🇭

    A long-standing problem in primordial cosmology is to understand the precise relation between the stochastic formalism and standard perturbation theory for light scalar fields in inflationary spacetimes. A complete correspondence between the two frameworks has remained elusive, even for a single self-interacting spectator field on a fixed de Sitter background. In this Letter, we revisit the assumptions underlying the derivation of the Langevin and Fokker-Planck equations that form the basis of the stochastic approach. We show that the standard stochastic treatment is effectively equivalent to neglecting super-long-wavelength modes beyond the observable range described by these equations. Using perturbation theory, we quantify how these modes enter through virtual loop effects and demonstrate that, once treated consistently, they induce definite corrections to both the Langevin and Fokker-Planck equations.

    hep-thastro-ph.COhep-ph9 citations
  38. 38*

    The maximal frequency of cosmic gravitons

    Massimo Giovannini🇨🇭

    We show that the maximal frequency of cosmic gravitons must not exceed the THz domain. From a classical viewpoint, both in conventional inflationary scenarios and in bouncing models the largest frequency of the spectrum overshoots the MHz band even if its specific signature is model dependent. According to a quantum mechanical perspective the maximal frequency is instead associated with the range of energies where a single pair of gravitons with opposite (comoving) three-momenta is produced. The upper limit on the largest frequency determines the minimal chirp amplitude [typically ] required for a direct detection of a cosmic signal in the THz band. Below this limiting frequency the minimal chirp amplitude can be enhanced so that the optimal range ultimately depends on the physical properties of the diffuse backgrounds. In case a hypothetical instrument (at present just a figment of a hopeful imagination) would reach chirp amplitudes down to in the MHz or GHz bands, the Bose-Einstein correlations could be used to probe the properties of cosmic gravitons and their super-Poissonian statistics.

    gr-qcastro-ph.COhep-exhep-ph+1PLB(2024)·10 citations
  39. 39*

    Primordial Black Holes and Induced Gravitational Waves from a Smooth Crossover beyond Standard Model

    Albert Escrivà🇯🇵 · Yuichiro Tada🇯🇵 · Chul-Moon Yoo🇯🇵

    Gravitational waves (GWs) induced by primordial fluctuations can be affected by the modification of the sound speed and the equation of state parameter once the curvature fluctuations reenter the cosmological horizon. That softening can also significantly boost the production of Primordial Black Holes (PBHs) at the mass scale where the softening arises. In this work, we consider a hypothetical softening of and caused by a smooth crossover beyond Standard Model theories, for what we numerically compute the secondary induced GW considering the case of a flat scale-invariant power spectrum. We find that if the amplitude of the power spectrum is sufficiently large, the characteristic feature of the GW signal caused by the smooth crossover can be detected by future space-based gravitational wave interferometers and differentiated from the pure radiation case. At the same time, depending on the mass scale where the crossover occurs, such a scenario can have compatibility with PBHs being all the dark matter when , with a mass function very sharply peaked around the horizon mass scale of the minimum of the sound speed. Our results show that the GW signal can be used to resolve the existing degeneracy of sharply peaked mass function caused by peaked power spectrums and broad ones in the presence of softenings of and .

    astro-ph.COgr-qchep-phPRD(2024)·18 citations
  40. 40*

    Polarization Measurements of and He Beams at RHIC and Future EIC Using the Polarized Atomic Hydrogen Gas Jet Target

    Andrei Poblaguev🇺🇸

    At the Relativistic Heavy-Ion Collider (RHIC), the Polarized Atomic Hydrogen Gas Jet Target polarimeter (HJET) is employed for the precise measurement of the absolute transverse (vertical) polarization of proton beams, achieving low systematic uncertainties of approximately . The acquired experimental data not only facilitated the determination of single and double spin analyzing powers for 100 and 255 GeV proton beams but also revealed a non-zero Pomeron spin-flip contribution through a Regge fit. Preliminary results obtained for forward inelastic and elastic analyzing powers will be discussed. The success of HJET at RHIC suggests its potential application for proton beam polarimetry at the upcoming Electron-Ion Collider (EIC), aiming for an accuracy of 1\%. Moreover, the provided analysis indicates that the RHIC HJET target can serve as a tool for the precision calibration, with the required accuracy, of the He beam polarization at the EIC.

    nucl-exhep-exhep-phUniverse(2024)·4 citations
  41. 41*

    Fixed point actions from convolutional neural networks

    Kieran Holland🇺🇸 · Andreas Ipp🇦🇹 · David I. Müller🇦🇹 · Urs Wenger🇨🇭

    Lattice gauge-equivariant convolutional neural networks (L-CNNs) can be used to form arbitrarily shaped Wilson loops and can approximate any gauge-covariant or gauge-invariant function on the lattice. Here we use L-CNNs to describe fixed point (FP) actions which are based on renormalization group transformations. FP actions are classically perfect, i.e., they have no lattice artifacts on classical gauge-field configurations satisfying the equations of motion, and therefore possess scale invariant instanton solutions. FP actions are tree-level Symanzik-improved to all orders in the lattice spacing and can produce physical predictions with very small lattice artifacts even on coarse lattices. We find that L-CNNs are much more accurate at parametrizing the FP action compared to older approaches. They may therefore provide a way to circumvent critical slowing down and topological freezing towards the continuum limit.

    hep-latcs.LGhep-phstat.MLPoS(2024)·8 citations
  42. 42*

    Coexistence Test of Primordial Black Holes and Particle Dark Matter from Diffractive Lensing

    Han Gil Choi🇰🇷 · Sunghoon Jung🇰🇷 · Philip Lu🇰🇷 · Volodymyr Takhistov🇯🇵

    If dark matter (DM) consists of primordial black holes (PBHs) and particles simultaneously, PBHs are generically embedded within particle DM halos. Such ``dressed PBHs'' (dPBHs) are subject to modified constraints compared to PBHs and can contribute to significant DM abundance in the mass range . We show that diffractive lensing of chirping gravitational waves (GWs) from binary mergers can not only discover, but can also identify dPBH lenses and discriminate them from bare PBHs on the event-by-event basis, with potential to definitively establish the coexistence of subdominant PBHs and particle DM.

    astro-ph.COastro-ph.HEgr-qchep-phPRL(2024)·27 citations
  43. 43*

    Detecting cosmological scalar fields using orbital networks of quantum sensors

    Yu Li🇨🇦 · Ruolin Liu🇨🇦 · Conner Dailey🇨🇦 · Niayesh Afshordi🇨🇦

    In this Letter, we propose to detect the interaction of a hypothetical coherently evolving cosmological scalar field with an orbital network of quantum sensors, focusing on the GPS satellite network as a test example. Cosmological scenarios, such as a scalar-tensor theory for dark energy or the axi-Higgs model, suggest that such a field may exist. As this field would be (approximately) at rest in the CMB frame, it would exhibit a dipole as a result of the movement of our terrestrial observers relative to the CMB. While the current sensitivity of the GPS network is insufficient to detect a cosmological dipole, future networks of quantum sensors on heliocentric orbits, using state-of-the-art atomic clocks, can reach and exceed this requirement.

    gr-qcastro-ph.COastro-ph.IMhep-ph+1PRD(2024)·3 citations
  44. 44*

    On the IR Divergences in de Sitter Space: loops, resummation and the semi-classical wavefunction

    Sebastián Céspedes🇬🇧 · Anne-Christine Davis🇬🇧 · Dong-Gang Wang🇬🇧

    In this paper, we revisit the infrared (IR) divergences in de Sitter (dS) space using the wavefunction method, and explicitly explore how the resummation of higher-order loops leads to the stochastic formalism. In light of recent developments of the cosmological bootstrap, we track the behaviour of these nontrivial IR effects from perturbation theory to the non-perturbative regime. Specifically, we first examine the perturbative computation of wavefunction coefficients, and show that there is a clear distinction between classical components from tree-level diagrams and quantum ones from loop processes. Cosmological correlators at loop level receive contributions from tree-level wavefunction coefficients, which we dub classical loops. This distinction significantly simplifies the analysis of loop-level IR divergences, as we find the leading contributions always come from these classical loops. Then we compare with correlators from the perturbative stochastic computation, and find the results there are essentially the ones from classical loops, while quantum loops are only present as subleading corrections. This demonstrates that the leading IR effects are contained in the semi-classical wavefunction which is a resummation of all the tree-level diagrams. With this insight, we go beyond perturbation theory and present a new derivation of the stochastic formalism using the saddle-point approximation. We show that the Fokker-Planck equation follows as a consequence of two effects: the drift from the Schrödinger equation that describes the bulk time evolution, and the diffusion from the Polchinski's equation which corresponds to the exact renormalization group flow of the coarse-grained theory on the boundary. Our analysis highlights the precise and simple link between the stochastic formalism and the semi-classical wavefunction.

    hep-thastro-ph.COgr-qchep-phJHEP(2024)·83 citations
  45. 45*

    Theoretical Developments in Lattice Gauge Theory for Applications in Double-beta Decay Processes and Quantum Simulation

    Saurabh V. Kadam🇺🇸

    Double beta decays are rare nuclear processes that can occur in two modes: two-neutrino double beta decay, observed in the Standard Model, and neutrinoless double beta decay, a hypothetical process with profound implications for Particle Physics. To draw reliable conclusions from their experimental constraints, it is necessary to have accurate predictions of the underlying hadronic interactions described by quantum chromodynamics (QCD), a non-Abelian gauge theory with the symmetry group SU(3). QCD predictions require non-perturbative methods for calculating observables, and lattice QCD (LQCD), a numerical method based on QCD formulated on a finite space-time grid, is the only reliable first-principles technique for obtaining quantitative results. However, LQCD needs formal prescriptions to match numerical results with observables. This thesis provides such prescriptions for double beta decays using the finite volume effects in the LQCD framework. Matching relations that connect two-nucleon double beta decay amplitudes to quantities accessible via LQCD calculations, namely the nuclear matrix elements and two-nucleon energy spectra in a finite volume are provided. The impact of uncertainties is examined on the precision with which low-energy constants of the corresponding effective field theories can be determined from future LQCD calculations. Hamiltonian simulation of QCD is another non-perturbative method of solving QCD which can be more suitable in some cases than the conventional LQCD. The rise of tensor network methods and quantum simulation has made Hamiltonian simulation of lattice gauge theories (LGTs) a reality. Towards the goal of simulating QCD, a loop-string-hadron (LSH) formulation of an SU(3) LGT with matter in 1+1 dimensions is developed in this thesis, motivated by recent studies that showed the LSH formulation of an SU(2) LGT to be advantageous over other formulations.

    hep-lathep-phnucl-thquant-ph6 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.