Tue·Feb 15, 2022Tuesday·February 15, 2022

1. 01*

   Picking the low-hanging fruit: testing new physics at scale with active learning

   Juan Rocamonde🇬🇧 · Louie Corpe🇨🇭 · Gustavs Zilgalvis🇬🇧 · Maria Avramidou🇬🇧 · Jon Butterworth🇬🇧

   Since the discovery of the Higgs boson, testing the many possible extensions to the Standard Model has become a key challenge in particle physics. This paper discusses a new method for predicting the compatibility of new physics theories with existing experimental data from particle colliders. Using machine learning, the technique obtained comparable results to previous methods (>90% precision and recall) with only a fraction of their computing resources (<10%). This makes it possible to test models that were impossible to probe before, and allows for large-scale testing of new physics theories.

   hep-phSciPost Phys.(2022)·10 citations
2. 02*

   Constrained Vector-like quark model with perturbative unitarity

   E. Accomando🇬🇧 · J. Brannigan🇬🇧 · J. Gunn🇬🇧 · Y. Huyan🇬🇧 · S. Mulligan🇬🇧

   We propose a Vector-like quark (VLQ) model constrained by the requirement of perturbative unitarity. In this scenario, the neutral and charged couplings of the new heavy VLQs to SM quarks and bosons are strictly related. We derive the corresponding sum rules and display the definite structure of the couplings. We analyse, qualitatively, the phenomenological consequences of this model in terms of expected width, production mechanism and decay channels. We show that the upcoming LHC run 3 could have sensitivity to such particles but the search strategy should be adapted to cover wide resonances decaying mainly in the charged channel T(B) -> Wq.

   hep-ph3 citations
3. 03*

   Generators and the (Accelerated) Future

   Joshua Isaacson🇺🇸

   With the High Luminosity LHC coming online in the near future, event generators will need to provide very large event samples to match the experimental precision. Currently, the estimated cost to generate these events exceeds the computing budget of the LHC experiments. To address these issues, the computing efficiency of event generators need to be improved. Many different approaches are being taken to achieve this goal. I will cover the ongoing work on implementing event generators on the GPUs, machine learning the matrix element, machine learning the phase space, and minimizing the number of negative weight events.

   hep-phJ.Phys.Conf.Ser.(2023)·0 citations
4. 04*

   Production of $\psi (4040)$, $\psi (4160)$, and $\psi (4415)$ mesons in hadronic matter

   Li-Yuan Li🇨🇳 · Xiao-Ming Xu🇨🇳 · H. J. Weber🇺🇸

   We present the first study of production of $\psi (4040)$, $\psi (4160)$, and $\psi (4415)$ mesons in hadronic matter. Quark interchange between two colliding charmed mesons leads to the production of the three mesons. We calculate unpolarized cross sections for the reactions, $D\bar{D}\to \rho R$, $D{\bar{D}}^{\ast }\to \pi R$, $D{\bar{D}}^{\ast }\to \rho R$, $D^{\ast }\bar{D}\to \pi R$, $D^{\ast }\bar{D}\to \rho R$, $D^{\ast }{\bar{D}}^{\ast }\to \pi R$, and $D^{\ast }{\bar{D}}^{\ast }\to \rho R$, where $R$ stands for $\psi (4040)$, $\psi (4160)$, and $\psi (4415)$. In the temperature region covering hadronic matter the peak cross sections of producing $\psi (4040)$ are similar to or larger than the ones of producing $\psi (4415)$, and the latter are generally larger than those of producing $\psi (4160)$. With the cross sections we establish new master rate equations for $\psi (4040)$, $\psi (4160)$, and $\psi (4415)$. The equations are solved for central Pb-Pb collisions at $\sqrt{s_{NN}}=5.02$ TeV at the Large Hadron Collider. Solutions of the equations show that the $\psi (4040)$ number density at kinetic freeze-out of hadronic matter is larger than the $\psi (4415)$ number density which is larger than the $\psi (4160)$ number density.

   hep-phhep-exnucl-exnucl-thPRD(2022)·2 citations
5. 05*

   Bounds on sterile neutrino lifetime and mixing angle with active neutrinos by global 21 cm signal

   Pravin Kumar Natwariya🇮🇳 · Alekha C. Nayak🇮🇳

   Sterile neutrinos can be a possible candidate for dark matter. Sterile neutrinos are radiatively unstable and can inject photon energy into the intergalactic medium (IGM). The injection of photon energy into IGM can modify the temperature and ionization history of IGM gas during cosmic dawn. Theoretical models based on the {\Lambda}CDM framework predict an absorption profile in the 21 cm line during the cosmic dawn era. Recently, the Experiment to Detect the Global Epoch of Reionization Signature (EDGES) collaboration confirmed such an adsorption signal. Injection of energy into IGM can modify the absorption amplitude in the 21 cm signal. Considering the 21 cm absorption signal at cosmic dawn, we constrain the lifetime of sterile neutrinos and the mixing angle of sterile neutrinos with active neutrinos. We also compare these bounds with other astrophysical observational bounds.

   hep-phastro-ph.COPLB(2022)·11 citations
6. 06*

   Artificial Dynamical Effects in Quantum Field Theory

   S. J. Brodsky🇺🇸 · A. Deur🇺🇸 · C. D. Roberts🇨🇳

   In Newtonian mechanics, inertial pseudoforces - or fictitious forces - appear in systems studied in non-Galilean reference frames; e.g., a centrifugal force seems to arise if the dynamics is analyzed in a rotating reference frame. The equivalent of Galilean invariance for relativistic kinematics is Poincaré invariance; analogous artificial effects may arise in relativistic quantum field theory (QFT) if a system is studied in a framework violating Poincaré invariance. We highlight how such issues complicate the traditional canonical quantization of QFTs and can lead to a subjective description of natural phenomena. In fact, if the system involves the strong interaction, obtaining objective results can become an intractable problem using canonical quantization because the pseudoforces are essentially nonperturbative. In contrast, the treatment of the same problem using light-front (LF) quantization is free of spurious pseudoeffects because Poincaré invariance is manifest; thus the treatment of strong interaction problems becomes simpler. These statements are illustrated using several examples: the Gerasimov-Drell-Hearn (GDH) relation, a fundamental feature of QFT; the absence of any measurable impact of Lorentz contraction in high-energy collisions; and the fictitious character of vacuum fluctuation contributions to the cosmological constant.

   hep-phhep-lathep-thnucl-thNature Rev.Phys.(2022)·27 citations
7. 07*

   Comment on "$Z_c$-like spectra from QCD Laplace sum rules at NLO"

   Zhi-Gang Wang🇨🇳

   In Phys. Rev. {\bf D103} (2021) 074015 (arXiv:2101.07281), huge (or largest) mass gaps between the ground states and first radial excited states for the tetraquark molecular states are obtained, $\Delta =1.70\sim 2.35\mathrm{GeV}$. We explore the problems in the operator product expansion, Borel windows, etc, in details.

   hep-ph1 citation
8. 08*

   Weak Radiative Decays of Anti-triplet Bottomed Baryons in Light-Front Quark Model

   Chao-Qiang Geng🇨🇳 · Chia-Wei Liu🇨🇳 · Zheng-Yi Wei🇨🇳 · Jiabao Zhang🇨🇳

   We study the weak radiative decays of ${\mathbf{B}}_b\to {\mathbf{B}}_n\gamma$ with ${\mathbf{B}}_{b(n)}$ the anti-triplet-bottom (octet) baryons in the light front quark model. We obtain that $\mathcal{B}({\Lambda }_b\to \Lambda \gamma )=(7.1\pm 0.3)\times 10^{-6}$, which agrees well with the current experimental value of $(7.1\pm 1.7)\times 10^{-6}$. We predict that $\mathcal{B}({\Xi }_b^0\to {\Xi }^0\gamma )=(1.0\pm 0.1)\times 10^{-5}$ and $\mathcal{B}({\Xi }_b^{-}\to {\Xi }^{-}\gamma )=(1.1\pm 0.1)\times 10^{-5}$, which are consistent with the latest upper limits set by the LHCb collaboration. In addition, we find that the $SU(3{)}_F$ flavor symmetry breaking effects for the modes related to the $b\to d\gamma$ transition can be as large as $20\%$.

   hep-phPRD(2022)·15 citations
9. 09*

   Constraining the Cosmic Strings Gravitational Wave Spectra in No Scale Inflation with Viable Gravitino Dark matter and Non Thermal Leptogenesis

   Waqas Ahmed🇨🇳 · M. Junaid🇵🇰 · Salah Nasri🇦🇪 · Umer Zubair🇺🇸

   We revisit the hybrid inflation model gauged by $U(1{)}_{B-L}$ extension of the Minimal Supersymmetric Standard Model (MSSM) in a no-scale background. Considering a single predictive framework, we study inflation, leptogenesis, gavitino cosmology, and the stochastic background of gravitational waves produced by metastable cosmic strings. The spontaneous breaking of $U(1{)}_{B-L}$ at the end of inflation produces a network of metastable cosmic strings while, the interaction between $U(1{)}_{B-L}$ Higgs field and the neutrinos generate heavy Majorana masses for the right-handed neutrinos. The heavy Majorana masses explain the tiny neutrino masses via the seesaw mechanism, a realistic scenario for reheating and non-thermal leptogenesis. We show that a successful non-thermal leptogenesis and a stable gravitino as a dark matter candidate can be achieved for a wide range of reheating temperatures and $U(1{)}_{B-L}$ symmetry breaking scales. The possibility of realizing metastable cosmic strings in a grand unified theory (GUT) setup is briefly discussed. We find that a successful reheating with non-thermal leptogenesis and gravitino dark matter restrict the allowed values of string tension to a narrow range $10^{-9}\lesssim G{\mu }_{CS}\lesssim 8\times 10^{-6}$, predicting a stochastic gravitational-wave background that lies within the 1-$\sigma$ bounds of the recent NANOGrav 12.5-yr data, as well as within the sensitivity bounds of future GW experiments.

   hep-phgr-qcPRD(2022)·28 citations
10. 10*

    Muon g-2, Neutralino Dark Matter and Stau NLSP

    Mario E. Gomez🇪🇸 · Qaisar Shafi🇺🇸 · Amit Tiwari🇺🇸 · Cem Salih Un🇹🇷

    We explore the implications of resolving the muon g-2 anomaly in a SU(4)_c x SU(2)_L x SU(2)_R model, where the soft supersymmetry breaking scalar and gaugino masses break the left-right (LR) symmetry. A 2 sigma resolution of the anomaly requires relatively light sleptons, chargino and LSP neutralino. The stau turns out to be the NLSP of mass <~ 400 GeV, and the sleptons from the first two families can be as heavy as about 800 GeV. The chargino is also required to be lighter than about 600 GeV to accommodate the muon g-2 solutions consistent with the dark matter relic density constraint. The dominant right-handed nature of the light slepton states suppress the sensitivity of possible signals which can be probed in Run3 experiments at the LHC. We also discuss the impact of accomodating the Higgs boson mass and the vacuum stability of the scalar potential for these solutions. The Higgsinos are heavier than about 4 TeV, and the LSP neutralino has the correct relic density if it is Bino-like. We identify stau-neutralino coannihilation as the dominant mechanism for realizing the desired dark matter relic density, with sneutrino-neutralino coannihiliation playing a minor role. These bino-like dark matter solutions can yield a spin-independent scattering cross-section on the order of 10^{-3} pb which hopefully, can be expected to be tested in the near future.

    hep-phEPJC(2022)·24 citations
11. 11*

    Doubly heavy tetraquarks in a chiral-diquark picture

    Yonghee Kim🇯🇵 · Makoto Oka🇯🇵 · Kei Suzuki🇯🇵

    Energy spectrum of doubly heavy tetraquarks, $T_{QQ}$ ($QQ\bar{q}\bar{q}$ with $Q=c,b$ and $q=u,d,s$), is studied in the potential chiral-diquark model. Using the chiral effective theory of diquarks and the quark-diquark-based potential model, the $T_{bb}$, $T_{cc}$, and $T_{cb}$ tetraquarks are described as a three-body system composed of two heavy quarks and an antidiquark. We find several $T_{bb}$ bound states, while no $T_{cc}$ and $T_{cb}$ (deep) bound state is seen. We also study the change of the $T_{QQ}$ tetraquark masses under restoration of chiral symmetry.

    hep-phhep-exnucl-thPRD(2022)·54 citations
12. 12*

    Accessing Polarized Fragmentation Functions at the Unpolarized EIC and BELLE Experiments

    Shu-yi Wei🇨🇳

    We briefly report our recent progress on the study of the polarized fragmentation functions of $\Lambda$ hyperon in unpolarized semi-inclusive deep-inelastic scatterings and electron-positron annihilations at low energies. In particular, we present a simple but practical method on how to measure the azimuthal-angle-dependent longitudinal polarization and the transverse polarization inside the production plane and bridge these observables to the corresponding structure functions and fragmentation functions at the leading twist. Our work diversifies the high energy reactions that can probe the polarized fragmentation functions.

    hep-phhep-exJPS Conf.Proc.(2022)·0 citations
13. 13*

    Energy dependence of the proton geometry in exclusive vector meson production

    Arjun Kumar🇮🇳 · Tobias Toll🇮🇳

    The gluon radius of the proton is expected to increase at small gluon momentum fractions $x$, an effect which has hitherto not been considered in the dipole model framework. We investigate the energy dependence of exclusive $J/\psi$, $\varphi$, and $\rho$ production by introducing three models for $x$ dependence of the gluon thickness function. We allow the transverse width of the proton to increase as $x$ decreases, using novel parametrisations in the spherical proton and the hotspot model. We compare these with a model where the number of hotspots increases as $x$ decreases and confront the models with HERA data. The models exhibit clear differences in the slope of the $t$-spectra and in the cross section ratios between coherent and incoherent events. Comparisons to $t$-slopes and $W_{\gamma p}$ measurements show a preference for models where the proton's size increases as $x$ decreases.

    hep-phnucl-thPRD(2022)·20 citations
14. 14*

    Recent progress for five-particle two-loop scattering amplitudes with an off-shell leg

    Jakub Kryś🇮🇹

    We report on the advances in the calculation of the two-loop scattering amplitudes for five-particle processes with one off-shell leg. Focusing on the production of a Higgs boson in association with a bottom quark pair, we outline how the newly developed technology allows us to overcome the computational bottlenecks. In particular, we discuss the use of finite field arithmetic and elucidate a convenient way to evaluate numerically the special functions appearing in the amplitudes.

    hep-phJ.Phys.Conf.Ser.(2023)·2 citations
15. 15*

    Heavy neutrinos at future linear e${}^{+}$e${}^{-}$ colliders

    Krzysztof Mękała🇵🇱 · Jürgen Reuter🇩🇪 · Aleksander Filip Żarnecki🇵🇱

    Neutrinos are among the most mysterious particles in nature. Their mass hierarchy and oscillations, as well as their antiparticle properties, are being intensively studied in experiments around the world. Moreover, in many models of physics beyond the Standard Model, the baryon asymmetry or the dark matter density in the Universe are explained by introducing new species of neutrinos. Among others, heavy neutrinos of Dirac or Majorana nature were proposed to solve open questions in High Energy Physics. Such neutrinos with masses above the EW scale could be produced at future linear e${}^{+}$e${}^{-}$ colliders, like the Compact LInear Collider (CLIC) or the International Linear Collider (ILC). We studied the possibility of observing decays of heavy Dirac and Majorana neutrinos in the $qq\ell$ final state with ILC running at 500 GeV and 1 TeV, and CLIC at 3 TeV. The analysis is based on the Whizard event generation and fast simulation of detector response with Delphes. Neutrinos with masses from 200 GeV to 3.2 TeV were considered. We estimated the limits on the production cross sections, interpreted them in terms of the neutrino-lepton coupling parameter $V_{\ell N}^2$ (effectively the neutrino mixing angle) and compared them with current limits coming from the LHC running at 13 TeV, as well as the expected limits from future hadron colliders. The limits for the future lepton colliders, extending down to the coupling values of $10^{-7}-10^{-6}$, are stricter than any other limit estimates published so far.

    hep-phhep-exJHEP(2022)·54 citations
16. 16*

    Stimulated vacuum emission and photon absorption in strong electromagnetic fields

    I. A. Aleksandrov🇷🇺 · A. Di Piazza🇩🇪 · G. Plunien🇩🇪 · V. M. Shabaev🇷🇺

    According to quantum electrodynamics (QED), a strong external field can make the vacuum state decay producing electron-positron pairs. Here we investigate emission of soft photons which accompanies a nonperturbative process of pair production. Our analysis is carried out within the Furry picture to first order in the fine-structure constant. It is shown that the presence of photons in the initial state gives rise to an additional (stimulated) channel of photon emission besides the pure vacuum one. On the other hand, the number of final (signal) photons includes also a negative contribution due to photon absorption within the pair production process. These contributions are evaluated and compared. To obtain quantitative predictions in the domain of realistic field parameters, we employ the WKB approach. We propose to use an optical probe photon beam, whose intensity changes as it traverses a spatial region where a strong electric component of a background laser field is present. It is demonstrated that relative intensity changes on the level of $1\%$ can be experimentally observed once the intensity of the strong background field exceeds $10^{27}{\text{W/cm}}^2$ within a large laser wavelength interval. This finding is expected to significantly support possible experimental investigations of nonlinear QED phenomena in the nonperturbative regime.

    hep-phhep-thPRD(2022)·10 citations
17. 17*

    The Higgs Boson Mass as Fundamental Parameter of the Minimal Supersymmetric Standard Model

    Rima El-Kosseifi🇫🇷 · Jean-Loic Kneur🇫🇷 · Gilbert Moultaka🇫🇷 · Dirk Zerwas🇫🇷

    In the Minimal Supersymmetric Standard Model (MSSM) the mass of the lightest neutral Higgs boson is determined by the supersymmetric parameters. In the $m_h$MSSM the precisely measured Higgs boson replaces the trilinear coupling $A_t$ as input parameter. Expressions are derived to extract $A_t$ in a semi-analytical form as a function of the light Higgs boson (pole) mass. An algorithm is developed and implemented at two--loop precision, generalizable to higher orders, to perform this inversion consistently. The result of the algorithm, implemented in the SuSpect spectrum calculator, is illustrated on a parameter set compatible with LHC measurements.

    hep-phhep-exEPJC(2022)·5 citations
18. 18*

    Semi-Equivariant GNN Architectures for Jet Tagging

    Daniel Murnane🇺🇸 · Savannah Thais🇺🇸 · Jason Wong🇺🇸

    Composing Graph Neural Networks (GNNs) of operations that respect physical symmetries has been suggested to give better model performance with a smaller number of learnable parameters. However, real-world applications, such as in high energy physics have not born this out. We present the novel architecture VecNet that combines both symmetry-respecting and unconstrained operations to study and tune the degree of physics-informed GNNs. We introduce a novel metric, the \textit{ant factor}, to quantify the resource-efficiency of each configuration in the search-space. We find that a generalized architecture such as ours can deliver optimal performance in resource-constrained applications.

    hep-phcs.LGhep-exphysics.comp-phJ.Phys.Conf.Ser.(2023)·9 citations
19. 19*

    Purity correction for cumulants of hyperon number distribution

    Toshihiro Nonaka🇯🇵

    We propose a purity correction to subtract effects of combinatorial backgrounds from cumulants of hyperon number distributions. We argue that cumulants and mix-cumulants of sidebands, whose yield is comparable with that of background particles in the signal region, can be used for the correction. The method is demonstrated in a simple toy model by introducing effects of reconstruction efficiencies and backgrounds. We show that topological cut parameters for hyperon reconstructions can be optimized to achieve the best statistical significance after purity and efficiency corrections. The method will enable us to measure cumulants of net-baryon, net-strangenss, and their correlations with better figure of merit than the conventional approach.

    hep-phhep-exnucl-exphysics.data-anNucl.Instrum.Meth.A(2022)·5 citations
20. 20*

    Dark Matter Effective Field Theory and an Application to Vector Dark Matter

    Jason Aebischer🇨🇭 · Wolfgang Altmannshofer🇺🇸 · Elizabeth E. Jenkins🇺🇸 · Aneesh V. Manohar🇺🇸

    The Standard Model Effective Field Theory (SMEFT) and the Low Energy Effective Field Theory (LEFT) can be extended by adding additional spin 0, 1/2 and 1 dark matter particles which are singlets under the Standard Model (SM) gauge group. We classify all gauge invariant interactions in the Lagrangian up to terms of dimension six, and present the tree-level matching conditions between the two theories at the electroweak scale. The most widely studied dark matter models, such as those based on the Higgs portal or on kinetic mixing between the photon and a dark photon, are based on dimension-four interactions with the SM sector. We consider a model with dark vector particles with a ${\mathbb{Z}}_2$ symmetry, so that the lightest dark matter particle is stable. The leading interaction with the SM is through dimension-six operators involving two dark vector field-strength tensors and the electromagnetic field-strength tensor. This model is a viable dark matter model in the freeze-in scenario for a wide range of parameters.

    hep-phJHEP(2022)·48 citations
21. 21*

    Probing Neutrino Mass Models through Resonances at Neutrino Telescopes

    K.S. Babu🇺🇸 · P.S. Bhupal Dev🇺🇸 · Sudip Jana🇩🇪

    We study the detection prospects of relatively light charged scalars in radiative Majorana neutrino mass models, such as the Zee model and its variants using scalar leptoquarks, at current and future neutrino telescopes. In particular, we show that these scalar mediators can give rise to Glashow-like resonance features in the ultra-high energy neutrino (UHE) event spectrum at the IceCube neutrino observatory and its high-energy upgrade IceCube-Gen2. The same scalars can also give rise to observable non-standard neutrino interactions (NSI), and we show that the UHE neutrinos provide a complementary probe of NSI. We also discuss an interesting possibility of producing such resonances by incoming sterile neutrino components in the case where neutrinos are pseudo-Dirac particles.

    hep-phastro-ph.HEhep-exInt.J.Mod.Phys.A(2022)·15 citations
22. 22*

    Particle production during inflation: A Bayesian analysis with CMB data from Planck 2018

    Suvedha Suresh Naik🇮🇳 · Kazuyuki Furuuchi🇮🇳 · Pravabati Chingangbam🇮🇳

    A class of inflationary models that involve rapid bursts of particle productions predict observational signatures, such as bump-like features in the primordial scalar power spectrum. In this work, we analyze such models by comparing their predictions with the latest CMB data from Planck 2018. We consider two scenarios of particle production. The first one is a simple scenario consisting of a single burst of particle production during observable inflation. The second one consists of multiple bursts of particle production that lead to a series of bump-like features in the primordial power spectrum. We find that the second scenario of the multi-bump model gives better fit to the CMB data compared to the concordance $\Lambda$CDM model. We carried out model comparisons using Bayesian evidences. From the observational constraints on the amplitude of primordial features of the multi-bump model, we find that the coupling parameter $g$ responsible for particle production is bound to be $g<0.05$.

    ↳ astro-ph.COhep-phhep-thJCAP(2022)·16 citations
23. 23*

    Generalized Symmetry Breaking Scales and Weak Gravity Conjectures

    Clay Cordova🇺🇸 · Kantaro Ohmori🇯🇵 · Tom Rudelius🇺🇸

    We explore the notion of approximate global symmetries in quantum field theory and quantum gravity. We show that a variety of conjectures about quantum gravity, including the weak gravity conjecture, the distance conjecture, and the magnetic and axion versions of the weak gravity conjecture can be motivated by the assumption that generalized global symmetries should be strongly broken within the context of low-energy effective field theory, i.e. at a characteristic scale less than the Planck scale where quantum gravity effects become important. For example, the assumption that the electric one-form symmetry of Maxwell theory should be strongly broken below the Planck scale implies the weak gravity conjecture. Similarly, the violation of generalized non-invertible symmetries is closely tied to analogs of this conjecture for non-abelian gauge theory. This reasoning enables us to unify these conjectures with the absence of global symmetries in quantum gravity.

    ↳ hep-thhep-phJHEP(2022)·105 citations
24. 24*

    Scaling properties of exclusive vector meson production cross section from gluon saturation

    Gregory Matousek🇺🇸 · Vladimir Khachatryan🇺🇸 · Jinlong Zhang🇨🇳

    It is already known from phenomenological studies that in exclusive deep-inelastic scattering off nuclei there appears to be a scaling behavior of vector meson production cross section in both nuclear mass number, $A$, and photon virtuality, $Q^2$, which is strongly modified due to gluon saturation effects. In this work we continue those studies in a realistic setup based upon using the Monte Carlo event generator Sar{\em t}re. We make quantitative predictions for the kinematics of the Electron-Ion Collider, focusing on this $A$ and $Q^2$ scaling picture, along with establishing a small region of squared momentum transfer, $t$, where there are signs of this scaling that may potentially be observed at the EIC. Our results are represented as pseudo-data of vector meson production diffractive cross section and/or their ratios, which are obtained by parsing data collected by the event generator through smearing functions, emulating the proposed detector resolutions for the future EIC.

    ↳ nucl-thhep-phnucl-exEur.Phys.J.Plus(2023)·2 citations
25. 25*

    Theory of kaon-nuclear systems

    Tetsuo Hyodo🇯🇵 · Wolfram Weise🇩🇪

    The strong interaction between an antikaon and a nucleon is at the origin of various interesting phenomena in kaon-nuclear systems. In particular, the interaction in the isospin $I=0$ channel is sufficiently attractive to generate a quasi-bound state, the $\Lambda (1405)$ resonance, below the $\bar{K}N$ threshold. Based on this picture, it may be expected that the $\bar{K}N$ interaction also generates quasi-bound states in kaon-nuclear systems, sometimes called kaonic nuclei. At the same time, the $\bar{K}N$ quasi-bound picture of the $\Lambda (1405)$ is also related to the discussion of hadronic molecules in hadron spectroscopy. Here an overview is presented of the theoretical studies developed for kaon-nucleon and kaon-nuclear systems. We start from the modern understanding of the $\Lambda (1405)$ resonance. We then discuss the $\bar{K}N$ interaction and various aspects of few-body kaonic nuclei. Heavier kaon-nuclear systems are examined from the viewpoint of nuclear many-body physics, with focus on the properties of antikaons in nuclear matter. Related topics, such as the $K^{-}p$ momentum correlation functions in high-energy collisions and the studies of kaonic atoms, are also discussed.

    ↳ nucl-thhep-ph15 citations
26. 26*

    Neutrinos from Gamma-ray Bursts

    Shigeo S. Kimura🇯🇵

    Gamma-ray bursts (GRBs) are the most luminous electromagnetic burst in the Universe. They occur when a rapidly rotating massive star collapses or a binary neutron star merges. These events leave a newborn central compact object, either a black hole or neutron star, which launches relativistic jets that emit the luminous gamma-ray signals. These jets can accelerate non-thermal protons, which are expected to produce high-energy neutrinos via photohadronic interactions. This Chapter briefly summarizes the current physical picture of GRBs, and discusses neutrino emissions from GRBs, including both prompt and afterglow phases. Neutrinos from sub-classes of GRBs, including low-luminosity GRBs and short GRBs, are also discussed.

    ↳ astro-ph.HEhep-ph52 citations
27. 27*

    Polynomial $\alpha$-attractors

    Renata Kallosh🇺🇸 · Andrei Linde🇺🇸

    Inflationary $\alpha$-attractor models can be naturally implemented in supergravity with hyperbolic geometry. They have stable predictions for observables, such as $n_s=1-2/N_e$, assuming that the potential in terms of the original geometric variables, as well as its derivatives, are not singular at the boundary of the hyperbolic disk, or half-plane. In these models, the potential in the canonically normalized inflaton field $\phi$ has a plateau, which is approached exponentially fast at large $\phi$. We call them exponential $\alpha$-attractors. We present a closely related class of models, where the potential is not singular, but its derivative is singular at the boundary. The resulting inflaton potential is also a plateau potential, but it approaches the plateau polynomially. We call them polynomial $\alpha$-attractors. Predictions of these two families of attractors completely cover the sweet spot of the Planck/BICEP/Keck data. The exponential ones are on the left, the polynomial are on the right.

    ↳ astro-ph.COgr-qchep-phhep-thJCAP(2022)·64 citations
28. 28*

    On-Shell Covariance of Quantum Field Theory Amplitudes

    Timothy Cohen🇺🇸 · Nathaniel Craig🇺🇸 · Xiaochuan Lu🇺🇸 · Dave Sutherland🇮🇹

    Scattering amplitudes in quantum field theory are independent of the field parameterization, which has a natural geometric interpretation as a form of `coordinate invariance.' Amplitudes can be expressed in terms of Riemannian curvature tensors, which makes the covariance of amplitudes under non-derivative field redefinitions manifest. We present a generalized geometric framework that extends this manifest covariance to $all$ allowed field redefinitions. Amplitudes satisfy a recursion relation that closely resembles the application of covariant derivatives to increase the rank of a tensor. This allows us to argue that (tree-level) amplitudes possess a notion of `on-shell covariance,' in that they transform as a tensor under any allowed field redefinition up to a set of terms that vanish when the equations of motion and on-shell momentum constraints are imposed. We highlight a variety of immediate applications to effective field theories.

    ↳ hep-thhep-phPRL(2023)·50 citations
29. 29*

    Geometry-Kinematics Duality

    Clifford Cheung🇺🇸 · Andreas Helset🇺🇸 · Julio Parra-Martinez🇺🇸

    We propose a mapping between geometry and kinematics that implies the classical equivalence of any theory of massless bosons -- including spin and exhibiting arbitrary derivative or potential interactions -- to a nonlinear sigma model (NLSM) with a momentum-dependent metric in field space. From this kinematic metric we construct a corresponding kinematic connection, covariant derivative, and curvature, all of which transform appropriately under general field redefinitions, even including derivatives. We show explicitly how all tree-level on-shell scattering amplitudes of massless bosons are equal to those of the NLSM via the replacement of geometry with kinematics. Lastly, we describe how the recently introduced geometric soft theorem of the NLSM, which universally encodes all leading and subleading soft scalar theorems, also captures the soft photon theorems.

    ↳ hep-thhep-phPRD(2022)·73 citations
30. 30*

    Hidden Variables of Gravity and Geometry and the Cosmological Constant Problem

    Nemanja Kaloper🇺🇸

    We extend General Relativity by promoting Planck scale and the cosmological constant into integration constants, interpreted as fluxes of $4$-forms hiding in the theory. When we include the charges of the $4$-forms, these `constants' can vary discretely from region to region. We explain how the cosmological constant problem can be solved in this new framework. When the cosmological constant picks up contributions from two different $4$-forms, with an irrational ratio of charges, the spectrum of its values is a very fine discretuum. When the charges are mutually irrational, $\frac{2{\kappa }_{\mathtt{eff}}^2{\kappa }^2|{\mathcal{Q}}_i|}{3{\mathcal{T}}_i^2}<1$, the discharge processes populating our discretuum will dynamically relax $\Lambda$, ceasing as $\Lambda$ approaches zero. Thus the theory exponentially favors a huge hierarchy $\Lambda /{\text{mpl}}^4\ll 1$ instead of $\Lambda /{\text{mpl}}^4\simeq 1$.

    ↳ hep-thastro-ph.COgr-qchep-phPRD(2022)·22 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.