HEP Phenomenology·hep-ph

Mon·Apr 1, 2024Monday·April 1, 2024

21 papers—11 primary·10 cross-listed·reconstructed*

01*
Spin asymmetries for $C$ -even quarkonium production as a probe of gluon distributions
Nanako Kato🇮🇹 · Luca Maxia🇳🇱 · Cristian Pisano🇮🇹
Within the framework of transverse momentum dependent factorization in combination with nonrelativistic QCD, we study charmonium and bottomonium production in hadronic collisions. We focus on quarkonium states with even charge conjugation, for which the color-singlet production mechanism is expected to be also dominant in the small transverse momentum region, $q_{T}^{2} ≪ 4 M_{c, b}^{2}$ . It is shown that the distributions of linearly polarized gluons inside unpolarized, longitudinally and transversely polarized protons contribute to the cross sections for scalar and pseudoscalar quarkonia in a very distinctive, parity-dependent way, whereas their effects on higher angular momentum states are strongly suppressed. We derive analytical expressions for single and double spin asymmetries, which would allow for the direct extraction of the gluon transverse momentum dependent distributions, mirroring the phenomenological studies of the Drell-Yan processes aimed at the extraction of their quark counterparts. By adopting Gaussian models for the gluon TMDs, which fulfill without saturating everywhere their positivity bounds, we provide numerical predictions for the transverse single-spin asymmetries. These observables could be measured at LHCSpin, the fixed target experiment planned at the LHC.
hep-phhep-exPRD(2024)·11 citations
02*
Compton scattering in Bandos-Lechner-Sorokin-Townsend nonlinear electrodynamics
Yang Shi🇨🇳 · Towe Wang🇨🇳
The nonlinear electrodynamics proposed by Bandos, Lechner, Sorokin and Townsend is a remarkable theory that unifies Maxwell, Bialynicki-Birula and ModMax theories, which are known theories invariant under conformal transformations and electromagnetic duality transformations. In the Bandos-Lechner-Sorokin-Townsend nonlinear electrodynamics, we calculate the energy flux density, dispersion relations, refractive indices, phase and group velocities of plane waves as well as the changes of the photon wavelength in the Compton scattering process in the presence of a constant uniform electromagnetic background. Our results are useful for testing and constraining this new theory of nonlinear electrodynamics.
hep-phphysics.opticsNPB(2025)·3 citations
03*
The status of New Physics in $b \to c ℓ ν$ transitions
Marco Fedele🇩🇪
Motivated by the recent theoretical and experimental developments in $b \to c ℓ ν$ transitions, the aim of these proceedings is to critically analyse the current situation in this sector. In particular, we will inspect the possibility of explaining the current anomalous pattern by means of New Physics effects coupled with light charged leptons, motivated both by the measurement of the LFUV ratio $R (Λ_{c})$ and by the recent application of the Dispersive Matrix approach to estimate Form Factors in $B \to D^{*}$ transitions. These proceedings are based on Refs.~\cite{Fedele:2022iib,Fedele:2023ewe}.
hep-ph1 citation
04*
Three-particle formalism for multiple channels: the $η π π + K K π$ system in isosymmetric QCD
Zachary T. Draper🇺🇸 · Stephen R. Sharpe🇺🇸
We generalize previous three-particle finite-volume formalisms to allow for multiple three-particle channels. For definiteness, we focus on the two-channel $η π π$ and $K K π$ system in isosymmetric QCD, considering the positive $G$ parity sector of the latter channel, and neglecting the coupling to modes with four or more particles. The formalism we obtain is thus appropriate to study the $b_{1} (1235)$ and $η (1295)$ resonances. The derivation is made in the generic relativistic field theory approach using the time-ordered perturbation theory method. We study how the resulting quantization condition reduces to that for a single three-particle channel when one drops below the upper ( $K K π$ ) threshold. We also present parametrizations of the three-particle K matrices that enter into the formalism.
hep-phhep-latJHEP(2024)·17 citations
05*
Deriving Neutron Star Equation of State from AdS/QCD
Wei Li🇨🇳 · Jing-Yi Wu🇨🇳 · Kilar Zhang🇨🇳
Neutron stars are among the main targets for gravitational wave observatories, however, their equation of state is still not well established. Mainly phenomenological models with many parameters are widely used by far, while theoretical models are not so practical. In arXiv:1902.08477, a theoretical equation of state with only one parameter is derived from Witten-Sakai-Sugimoto model, as an application of AdS/QCD, where pointlike instanton case is taken into consideration. When the tidal deformability constraint from gravitational wave event is satisfied, the maximum mass is about 1.7 solar masses. Now we upgrade this model to instanton gas, with one more variable, the instanton width. This is not naively a free parameter, but a function of the chemical potential. Thus we end up with a more complicated and accurate model, but still with only one adjustable parameter. In this case, we find the maximum mass becomes 1.85 solar masses. This is an encouraging result, as a theoretically derived model.
hep-phastro-ph.HEgr-qchep-thResults Phys.(2024)·6 citations
06*
A realistic theory of $E_{6}$ unification through novel intermediate symmetries
K.S. Babu🇺🇸 · Borut Bajc🇸🇮 · Vasja Susič🇨🇿
We propose a non-supersymmetric $E_{6}$ GUT with the scalar sector consisting of $650 \oplus 35 1^{'} \oplus 27$ . Making use of the first representation for the initial symmetry breaking to an intermediate stage, and the latter two representations for second-stage breaking to the Standard Model and a realistic Yukawa sector, this theory represents the minimal $E_{6}$ GUT that proceeds through one of the intermediate stages that are novel compared to $SU (5)$ or $SO (10)$ GUT: trinification $SU (3)_{C} \times SU (3)_{L} \times SU (3)_{R}$ , $SU (6) \times SU (2)$ and flipped $SO (10) \times U (1)$ . We analyze these possibilities under the choice of vacuum that preserves a $Z_{2}$ ``spinorial parity'', which disentangles the chiral and vector-like fermions of $E_{6}$ and provides a dark matter candidate in the form of a (scalar) inert doublet. Three cases are shown to consistently unify under the extended survival hypothesis (with minimal fine-tuning): trinification symmetry $SU (3)_{C} \times SU (3)_{L} \times SU (3)_{R}$ with either $L R$ or $C R$ parity, and $SU (6)_{C R} \times SU (2)_{L}$ . Although the successful cases give a large range for proton lifetime estimates, all of them include regions consistent with current experimental bounds and within reach of forthcoming experiments. The scenario investigated in this paper essentially represents the unique (potentially) viable choice in the class of $E_{6}$ GUTs proceeding through a novel-symmetry intermediate stage, since non-minimal alternatives seem to be intrinsically non-perturbative.
hep-phJHEP(2024)·8 citations
07*
Probing Heavy Charged Higgs Boson Using Multivariate Technique at Gamma-Gamma Collider
Ijaz Ahmed🇵🇰 · Abdul Quddus🇵🇰 · Jamil Muhammad🇰🇷 · Muhammad Shoaib🇵🇰 · Saba Shafaq🇵🇰
The current study explores the production of charged Higgs particles through photon-photon collisions within the Two Higgs Doublet Model context, including one-loop-level scattering amplitude of Electroweak and QED radiation. The cross-section has been scanned for plane ( $m_{ϕ^{0}}, s$ ) investigating the process of $γ γ \to H^{+} H^{-}$ . Three particular numerical scenarios low- $m_{H}$ , non-alignment, and short-cascade are employed. Hence using $h^{0}$ for low- $m_{H^{0}}$ and $H^{0}$ for non-alignment and short-cascade scenario, the new experimental and theoretical constraints are applied.The decay channels for charged Higgs particles are examined in all the scenarios along with the analysis for cross-sections revealing that at low energy it is consistently higher for all scenarios. However as $s$ increases, it reaches a peak value at 1TeV for all benchmark scenarios. The branching ratio of the decay channels indicates that for non-alignment, the mode of decay $W^{\pm} h^{0}$ takes control %{} when $B R (H^{\pm} \to W^{\pm} H^{0})$ decreases at larger values of $m_{H^{0}}$ .} and for short cascade the prominent decay mode remains $t b ˉ$ , while in the low- $m_{H}$ the dominant decay channel is of $W^{\pm} h^{0}$ . In our research, we employ contemporary machine-learning methodologies to investigate the production of high-energy Higgs Bosons within a 3TeV Gamma-Gamma collider. We have used multivariate approaches such as Boosted Decision Trees (BDT), LikelihoodD, and Multilayer Perceptron (MLP) to show the observability of heavy-charged Higgs Bosons versus the most significant Standard Model backgrounds. The purity of the signal efficiency and background rejection are measured for each cut value.
hep-phCPC(2025)·5 citations
08*
Exploring Constraints on Simplified Dark Matter Model Through Flavour and Electroweak Observables
Lipika Kolay🇮🇳 · Soumitra Nandi🇮🇳
This study focuses on a combined analysis of various available inputs to constrain the parameter spaces of a simplified dark matter (SDM) model featuring a spin-0 mediator and fermionic dark matter (DM). The spin-0 mediator interacts with standard model (SM) fermions, SM gauge bosons, and DM. We constrain the parameter spaces of different relevant couplings, DM mass, and the mediator mass, using the data from flavour-changing charged and neutral current processes, CKM matrices, $W$ and $Z$ -pole observables, DM relic density, direct and indirect detection bounds. We have calculated bounds on the couplings from both separate and simultaneous analyses of the mentioned processes. We identify correlated parameter spaces for all the relevant parameters which include the couplings and the masses. For the DM and mediator masses, we have scanned the region between 100 GeV and 1000 GeV. Using our results, we have obtained bounds on the couplings of possible higher dimensional operators from which we can formulate our SDM.
hep-phJHEP(2024)·8 citations
09*
Resummation phenomenology and PDF determination for precision QCD at the LHC
Federico Silvetti🇮🇹
With the ongoing Run 3 of the LHC and its upcoming High-Luminosity upgrade, there is a growing need to study observables with high precision both experimentally and theoretically. To increase precision on the theory side, improvements of fixed-order perturbative predictions, resummation of logarithmic enhancements and accurate determination of proton structure are required. This thesis explores the latter two topics. We discuss high-energy logarithms and their resummation techniques, introducing an extension of the HELL formalism for multi-differential distributions in transverse momentum, rapidity and invariant mass. We apply this framework to heavy-quark pair production at the LHC, studying the kinematics of both a single quark and the final-state pair. An additional discussion is dedicated to a possible extension of the kt-factorisation framework, which underlies high-energy resummation, to capture next-to-leading logarithmic corrections. To test this hypothesis, we delve into the computation of a NLO off-shell coefficient function using Higgs-induced DIS in the infinite top mass limit as a benchmark process and report a partial result. Beside high-energy logarithms, we consider the determination of transverse-momentum distributions from a high mass system with additional QCD radiation and exclusive production cuts. Specifically, we focus on $H W^{+}$ production with a jet veto and analyse the Higgs transverse momentum spectrum at NNLO, using qt-subtraction. We complement the fixed order study with NNLL resummation of jet-veto logarithms and linear power correction in ptHW using the RadISH formalism. Finally, in the last project pertaining to this thesis we consider the problem of Parton Distribution Function determination. We propose a minimal parametrisation guided by physical arguments and investigate its performance in fitting the HERA dataset with NLO QCD theory predictions.
hep-ph11 citations
10*
Quantum simulation of entanglement and hadronization in jet production: lessons from the massive Schwinger model
Adrien Florio🇺🇸 · David Frenklakh🇺🇸 · Kazuki Ikeda🇺🇸 · Dmitri E. Kharzeev🇺🇸 · Vladimir Korepin🇺🇸 · Shuzhe Shi🇨🇳 · Kwangmin Yu🇺🇸
The possible link between entanglement and thermalization, and the dynamics of hadronization are addressed by studying the real-time response of the massive Schwinger model coupled to external sources. This setup mimics the production and fragmentation of quark jets, as the Schwinger model and QCD share the properties of confinement and chiral symmetry breaking. By using quantum simulations on classical hardware, we study the entanglement between the produced jets, and observe the growth of the corresponding entanglement entropy in time. This growth arises from the increased number of contributing eigenstates of the reduced density matrix with sufficiently large and close eigenvalues. We also investigate the physical nature of these eigenstates, and find that at early times they correspond to fermionic Fock states. We then observe the transition from these fermionic Fock states to meson-like bound states as a function of time. In other words, we observe how hadronization develops in real time. At late times, the local observables at mid-rapidity (such as the fermion density and the electric field) approach approximately constant values, suggesting the onset of equilibrium and approach to thermalization.
hep-phhep-thnucl-thquant-phPRD(2024)·52 citations
11*
N $^{3}$ LO soft-gluon corrections in single-particle-inclusive kinematics and $H^{+} H^{-}$ production
Nikolaos Kidonakis🇺🇸 · Alberto Tonero🇺🇸
We calculate the complete soft-gluon corrections for the production of colorless final states through N $^{3}$ LO in single-particle-inclusive kinematics. We present explicit analytical results and use them to study higher-order QCD corrections for the production of a heavy charged Higgs pair ( $H^{+} H^{-}$ ) via quark-antiquark annihilation in the Two-Higgs-Doublet Model at LHC energies. We calculate the NNLO soft-gluon and virtual QCD corrections as well as the N $^{3}$ LO soft-gluon corrections to the total cross section and the charged-Higgs rapidity distribution. This is the first calculation of complete N $^{3}$ LO soft-gluon corrections for a process in single-particle-inclusive kinematics, and the results can be applied to other processes with colorless final states.
hep-phJHEP(2024)·5 citations
12*
Multi-Messenger Astrology
Gwen Walker · Nick Ekanger🇺🇸 · R. Andrew Gustafson🇺🇸 · Sean Heston🇺🇸
It has long been accepted that the cosmos determine our personalities, relationships, and even our fate. Unlike our condensed matter colleagues - who regularly use quantum mechanics to determine the healing properties of crystals - astrology techniques have been unchanged since the 19th century. In this paper, we discuss how astrophysical messengers beyond starlight can be used to predict the future and excuse an $O (1)$ fraction of our negative personality traits.
↳ astro-ph.HEastro-ph.IMhep-ph0 citations
13*
Handling correlated systematic uncertainties on the CKM angle gamma
Alex Gilman🇬🇧
The current precision on the CKM angle $γ$ is driven by averages of measurements from multiple final states and multiple experiments. As the next generation of experiments targets a total experimental precision on $γ$ less than one degree, systematic uncertainties must be well-controlled and correlated uncertainties between different final states and across experiments must be fully understood. These proceedings examine the systematic uncertainties that arise in direct measurements of $γ$ and discuss the potential of each class of systematic uncertainties to prevent sub-degree precision.
↳ hep-exhep-ph0 citations
14*
Unobserving the Moon: the spurious possibility of orbital decoupling due to solar neutrino Arago spot
Henrik Viitasaari🇫🇮 · Oskari Färdig🇫🇮 · Joona H. Siljander🇫🇮 · A. Petrus Väisänen🇫🇮 · Aapo S. Harju🇫🇮 · Antti V. Nurminen🇫🇮 · Jami J. Kinnunen🇫🇮
The Arago spot is an intensity maximum at the center of a shadow created by constructive interference of diffracted waves around a spherical object. While the study of diffraction patterns usually concerns visible light, de Broglie's wave nature of matter makes diffraction theory applicable for particles, such as neutrinos, as well. During a solar eclipse, some of the neutrinos emitted by the Sun are diffracted by the Moon, resulting in a diffraction pattern that can be observed on Earth. In this paper we consider the theoretically emerging solar neutrino Arago spot as a means to measure the location of the Moon with high accuracy and consider its implication on the orbit of the Moon given Heisenberg's uncertainty principle. Our results indicate that the Moon is not at immediate risk of orbital decoupling due to the observation of a solar neutrino Arago spot.
↳ quant-phastro-ph.EPhep-phphysics.pop-ph0 citations
15*
Echoes from a long time ago: Chewbacca inflation
D. Sidious · S. Arcari🇮🇹 · N. Barbieri🇮🇹 · L. Bazzanini🇮🇹 · L. Caloni🇮🇹 · G. Galloni · R. Impavido · M. Lattanzi🇮🇹 · M. Lembo🇮🇹 · A. Raffaelli · N. Raffuzzi · S. S. Sirletti
The cosmic microwave background (CMB) radiation offers a unique avenue for exploring the early Universe's dynamics and evolution. In this paper, we delve into the fascinating realm of slow-roll inflation, contextualizing the primordial acoustic perturbations as the resonant echoes akin to the iconic sound of Chewbacca from the Star Wars universe. By extrapolating polynomial potentials for these primordial sounds, we illuminate their role in shaping the inflationary landscape. Leveraging this framework, we calculate the scalar spectral index ( $n_{s}$ ) and tensor-to-scalar ratio ( $r$ ), providing insights into the underlying physics governing the inflationary epoch. Employing a rigorous chi-square ( $χ^{2}$ ) analysis, we meticulously scrutinize the Planck data combined with that offered by the BICEP/Keck collaboration to identify the Chewbacca sound profile that best aligns with observational constraints. Our findings not only shed light on the intricate interplay between sound and cosmology but also unveil intriguing parallels between the cosmic symphony of the early universe and beloved cultural icons.
↳ astro-ph.COgr-qchep-phhep-th1 citation
16*
Rare Strange and Charm Decays at LHCb
Paras Naik🇬🇧
Thanks to the large cross-section for the production of strange and charm mesons at the Large Hadron Collider, LHCb has recently performed several new explorations of rare transitions that are highly suppressed or forbidden by the Standard Model: mostly flavour changing neutral current decays, but also lepton flavour violating decays. Physics beyond the Standard Model could contribute at tree and loop levels.
↳ hep-exhep-ph0 citations
17*
A single-bubble source for gravitational waves in a cosmological phase transition
Kfir Blum🇮🇱 · Mehrdad Mirbabayi🇮🇹
We show that quantum fluctuations of an expanding phase transition bubble give rise to gravitational wave (GW) emission, even when considering a single bubble, without bubble collisions or plasma effects. The ratio of GW energy to the total bubble energy reservoir increases with time as $\propto t$ . If the bubble expands for long enough before percolation destroys it, back-reaction due to the GW emission becomes important after $t_{br} \sim (16 π^{5}) m_{pl}^{2} R_{0}^{3}$ , where $R_{0}$ is the bubble nucleation radius and $m_{pl}$ is the reduced Planck mass. As seen by experiments today, the GW energy spectrum would appear blue. However, simple estimates suggest that the signal falls short of detection by even ambitious future experiments.
↳ gr-qcastro-ph.COhep-phJCAP(2024)·6 citations
18*
Circular reasoning: Solving the Hubble tension with a non- $π$ value of $π$
Jonas El Gammal🇳🇴 · Sven Günther · Emil Brinch Holm🇩🇰 · Andreas Nygaard🇩🇰
Recently, cosmology has seen a surge in alternative models that purport to solve the discrepancy between the values of the Hubble constant $H_{0}$ as measured by cosmological microwave background anisotropies and local supernovae, respectively. In particular, many of the most successful approaches have involved varying fundamental constants, such as an alternative value of the fine structure constant and time-varying values of the electron mass, the latter of which showed particular promise as the strongest candidate in several earlier studies. Inspired by these approaches, in this paper, we investigate a cosmological model where the value of the geometric constant $π$ is taken to be a free model parameter. Using the latest CMB data from Planck as well as baryon-acoustic oscillation data, we constrain the parameters of the model and find a strong correlation between $π$ and $H_{0}$ , with the final constraint $H_{0} = 71.3 \pm 1.1 km/s/Mpc$ , equivalent to a mere $1.5 σ$ discrepancy with the value measured by the SH0ES collaboration. Furthermore, our results show that $π = 3.206 \pm 0.038$ at $95%$ C.L., which is in good agreement with several external measurements discussed in the paper. Hence, we conclude that the $π Λ$ CDM model presented in this paper, which has only a single extra parameter, currently stands as the perhaps strongest solution to the Hubble tension.
↳ astro-ph.COhep-ph2 citations
19*
Probing Dark Matter Particles from Evaporating Primordial Black Holes via Electron Scattering in the CDEX-10 Experiment
Z. H. Zhang🇨🇳 · L. T. Yang🇨🇳 · Q. Yue🇨🇳 · K. J. Kang🇨🇳 · Y. J. Li🇨🇳 · H. P. An🇨🇳 · Greeshma C.🇹🇼 · J. P. Chang🇨🇳 · Y. H. Chen🇨🇳 · J. P. Cheng🇨🇳 · W. H. Dai🇨🇳 · Z. Deng🇨🇳 and 72 other authors
Dark matter (DM) is a major constituent of the Universe. However, no definite evidence of DM particles (denoted as `` $χ$ ") has been found in DM direct detection (DD) experiments to date. There is a novel concept of detecting $χ$ from evaporating primordial black holes (PBHs). We search for $χ$ emitted from PBHs by investigating their interaction with target electrons. The examined PBH masses range from 1 $\times$ 10 $^{15}$ to 7 $\times$ 10 $^{16}$ g under the current limits of PBH abundance $f_{P B H}$ . Using 205.4 kg $\cdot$ day data obtained from the CDEX-10 experiment conducted in the China Jinping Underground Laboratory, we exclude the $χ$ --electron ( $χ$ -- $e$ ) elastic-scattering cross section $σ_{χe} \sim 5 \times 1 0^{- 29}$ cm $^{2}$ for $χ$ with a mass $m_{χ} ≲$ 0.1 keV from our results. With the higher radiation background but lower energy threshold (160 eV), CDEX-10 fill a part of the gap in the previous work. If ( $m_{χ}$ , $σ_{χe}$ ) can be determined in the future, DD experiments are expected to impose strong constraints on $f_{P B H}$ for large $M_{P B H}$ s.
↳ hep-exhep-phphysics.ins-detSCPMA(2024)·12 citations
20*
Constraints on the Blazar-Boosted Dark Matter from the CDEX-10 Experiment
R. Xu🇨🇳 · L. T. Yang🇨🇳 · Q. Yue🇨🇳 · K. J. Kang🇨🇳 · Y. J. Li🇨🇳 · H. P. An🇨🇳 · Greeshma C.🇹🇼 · J. P. Chang🇨🇳 · Y. H. Chen🇨🇳 · J. P. Cheng🇨🇳 · W. H. Dai🇨🇳 · Z. Deng🇨🇳 and 72 other authors
We report new constraints on light dark matter (DM) boosted by blazars using the 205.4 kg day data from the CDEX-10 experiment located at the China Jinping Underground Laboratory. Two representative blazars, TXS 0506+56 and BL Lacertae are studied. The results derived from TXS 0506+56 exclude DM-nucleon elastic scattering cross sections from $4.6 \times 1 0^{- 33} c m^{2}$ to $1 \times 1 0^{- 26} c m^{2}$ for DM masses between 10 keV and 1 GeV, and the results derived from BL Lacertae exclude DM-nucleon elastic scattering cross sections from $2.4 \times 1 0^{- 34} c m^{2}$ to $1 \times 1 0^{- 26} c m^{2}$ for the same range of DM masses. The constraints correspond to the best sensitivities among solid-state detector experiments in the sub-MeV mass range.
↳ hep-exhep-phphysics.ins-det9 citations
21*
Deriving Ontological Statements from the Unnatural Higgs Mass
Johannes Branahl🇩🇪
We provide novel, metatheoretical arguments strengthening the position that the naturalness problem of the light Higgs mass is a pseudo-problem: No physics beyond the standard model of particle physics is needed to explain the small value of the Higgs boson. By evaluating previous successes of the guiding principle of technical naturalness, we restrict its applicability to non-fundamental phenomena in the realm of provisional theories within limited energy scales. In view of further breaches of autonomy of scales in apparently fundamental phenomena outside particle physics, the hierarchy problem of the Higgs mass is instead reinterpreted as an indication of the ontologically fundamental status of the Higgs boson. Applying the concept of Selective Realism justifies this seemingly contradictory attribution within the effective theories of the standard model of particle physics. Moreover, we argue that the ongoing naturalness debate about the Higgs mass is partly based on the adherence to the methodology of effective theories (often claimed to be universally applicable), for which there is no justification when dealing with presumably fundamental phenomena such as the Higgs mechanism, even if it is embedded into an effective theory.
↳ physics.hist-phhep-phFound.Phys.(2025)·0 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.