Thu·Jul 14, 2022Thursday·July 14, 2022

1. 01*

   About the bosonic decays of heavy Higgs states in the (N)MSSM

   Florian Domingo🇩🇪 · Sebastian Paßehr🇩🇪

   The heavy, doublet-dominated Higgs bosons expected in Two-Higgs-Doublet-Model-like extensions of the Standard Model are obvious targets for searches at high-energy colliders, and considerable activity in this sense is currently employed in analyzing the results of the Large Hadron Collider. For sufficiently heavy states, the $SU(2{)}_{\mathrm{L}}$ symmetry drastically constrains the decays of these new scalars. In models that contain only additional Higgs doublets, fermionic decay channels are expected to dominate, although some bosonic modes may lead to cleaner signals. The situation is very different if the Higgs sector is further extended by singlet states and the singlet-dominated scalars are kinematically accessible, in which case the Higgs-to-Higgs widths may even become dominant. Yet, a quantitative interpretation of the experimental data in terms of a specific model also runs through the control of radiative corrections in this model. In this paper, we examine the bosonic decays of the heavy, doublet-dominated Higgs states in the MSSM and the NMSSM at full one-loop order, insisting on the impact of the $SU(2{)}_{\mathrm{L}}$ symmetry and the effects of infrared type, in particular, the emergence of sizable non-resonant contributions to the three-boson final states.

   hep-phEPJC(2022)·8 citations
2. 02*

   Temperature and net baryochemical potential dependence of $\eta /s$ in a hybrid approach

   Niklas Götz🇩🇪 · Hannah Elfner🇩🇪

   In this work, the qualitative impact of the net baryochemical potential dependence of the shear viscosity to entropy density ratio $\eta /s$ in hydrodynamical simulations is studied. The effect of a predicted non-constant $\eta /s$(${\mu }_B$) is largely unexplored in hydrodynamic simulations. Previous studies focus only on a temperature dependence or even only a constant effective shear viscosity. This work addresses this issue by studying qualitatively the effect of a generalized $\eta /s$($T,{\mu }_B$) in the hybrid approach SMASH-vHLLE, composed of the hadronic transport approach SMASH and the (3+1)d viscous hydrodynamic code vHLLE. In order to reduce the bias of the result on the equation of state used in the hydrodynamic part of the model, $\eta /s$ is parameterized directly in the energy density and net baryon number density. The parameterization takes into account the constraints of matching to the transport coefficients in the hadronic phase, as well as pQCD results. This work compares the impact of the density dependence for different system sizes and energies and compares the observables with experimental results in the RHIC - BES region $\sqrt{s_{NN}}$ =7.7 - 39.0 GeV, as the effect of this generalization is especially relevant for intermediate collision energies, for which the system is in equilibrium for a relevant amount of time, but the net baryochemical potential does not vanish. It is shown that the effect of an explicit net baryon number dependence on the elliptic flow is negligible and only relevant in the early stages of the collision. Additionally, we find that the proposed parameterization could be a good proxy for the shear viscosity in the non-equilibrium hadronic transport stage.

   hep-phnucl-exnucl-thPRC(2022)·15 citations
3. 03*

   Muon $g-2$ anomaly in a left-right model with an inverse seesaw mechanism

   M. Ashry🇪🇬 · K. Ezzat🇪🇬 · S. Khalil🇪🇬

   We investigate the possibility of explanation for the muon anomalous magnetic moment $g_{\mu }-2$ in a left-right model with an inverse seesaw mechanism. We emphasize that the observed deviation from the Standard Model predictions can be accommodated in a large part of the parameter space of this class of models, where loops with massive neutrinos and charged Higgs boson as well as the weak $W$ boson contribute significantly to $g_{\mu }-2$. Stringent constraints due to lepton flavor violation $\mu \to e\gamma$, $\mu$-$e$~conversion and the electron anomalous magnetic moment $g_e-2$ are considered, and the results are compatible.

   hep-phPRD(2023)·9 citations
4. 04*

   Real-time hard-thermal-loop gluon self-energy in a semiquark-gluon plasma

   Yubiao Wang🇨🇳 · Qianqian Du🇨🇳 · Yun Guo🇨🇳

   In the real time formalism of the finite-temperature field theory, we compute the one-loop gluon self-energy in a semi-quark-gluon plasma (QGP) where a background filed $\mathcal{Q}$ has been introduced for the vector potential, leading to a non-trivial expectation value for the Polyakov loop in the deconfined phase. Explicit results of the gluon self-energies up to the next-to-leading order in the hard-thermal-loop approximation are obtained. We find that for the retarded/advanced gluon self-energy, the corresponding contributions at next-to-leading order are formally analogous to the well-known result at $\mathcal{Q}=0$ where the background field modification on the Debye mass is entirely encoded in the second Bernoulli polynomials. The same feature is shared by the leading order contributions in the symmetric gluon self-energy where the background field modification becomes more complicated, including both trigonometric functions and the Bernoulli polynomials. These contributions are non-vanishing and reproduce the correct limit as $\mathcal{Q}\to 0$. In addition, the leading order contributions to the retarded/advanced gluon self-energy and the next-to-leading order contributions to the symmetric gluon self-energy are completely new as they only survive at $\mathcal{Q}\ne 0$. Given the above results, we explicitly verify that the Kubo-Martin-Schwinger condition can be satisfied in a semi-QGP with non-zero background field.

   hep-phPRD(2022)·8 citations
5. 05*

   Analysis of the $P_{cs}(4338)$ and related pentaquark molecular states via the QCD sum rules

   Xiu-Wu Wang🇨🇳 · Zhi-Gang Wang🇨🇳

   In this work, we tentatively identify the $P_{cs}(4338)$ as the $\bar{D}{\Xi }_c$ molecular state, and distinguish the isospins of the current operators to explore the $\bar{D}{\Xi }_c$, $\bar{D}{\Lambda }_c$, ${\bar{D}}_s{\Xi }_c$, ${\bar{D}}_s{\Lambda }_c$, ${\bar{D}}^{\ast }{\Xi }_c$, ${\bar{D}}^{\ast }{\Lambda }_c$, ${\bar{D}}_s^{\ast }{\Xi }_c$ and ${\bar{D}}_s^{\ast }{\Lambda }_c$ molecular states without strange, with strange and with double strange in the framework of the QCD sum rules in details. The present explorations favor identifying the $P_{cs}(4338)$ ($P_{cs}(4459)$) as the $\bar{D}{\Xi }_c$ (${\bar{D}}^{\ast }{\Xi }_c$) molecular state with the spin-parity $J^P={\frac{1}{2}}^{-}$ (${\frac{3}{2}}^{-}$) and isospin $(I,I_3)=(0,0)$, the observation of their cousins with the isospin $(I,I_3)=(1,0)$ in the $J/\psi {\Sigma }^0/{\eta }_c{\Sigma }^0$ invariant mass distributions would decipher their inner structures.

   hep-phCPC(2023)·48 citations
6. 06*

   Inclusive $\tau$ Hadronic Decay Rate in a Renormalon-Free Gluon Condensate Scheme

   Miguel A. Benitez-Rathgeb🇦🇹 · Diogo Boito🇧🇷 · André H. Hoang🇦🇹 · Matthias Jamin🇦🇹 · Christoph Regner🇦🇹

   In a recent work by some of us it was shown that the long-standing discrepancy between the QCD perturbation series for the inclusive hadronic tau decay rate computed in the CIPT and FOPT expansion approaches can be understood from the fact that CIPT has an infrared (IR) sensitivity that it not compatible with the standard form of the operator production expansion (OPE). For concrete IR renormalon models for the QCD Adler function the resulting CIPT-FOPT discrepancy, the asymptotic separation, can be calculated analytically from the Borel representation of the CIPT series expansion. If the known perturbative corrections for the QCD Adler function at the 5-loop level already have a sizeable contribution from the asymptotic behavior related to the gluon condensate (GC) renormalon, the asymptotic separation is dominated by that renormalon. This implies that the CIPT expansion can be reconciled with FOPT, when a renormalon-free scheme for the GC is adopted. In this talk we discuss such a renormalon-free scheme for the GC, which involves perturbative subtractions in analogy to using short-distance quark mass schemes instead of the pole mass. Using a concrete realistic high-order Borel model for the Adler function consistent with the known corrections up to 5 loops and containing a sizeable GC renormalon contribution, we show that the CIPT-FOPT discrepancy can be avoided when switching to the renormalon-free GC scheme. At the same time, the perturbative convergence of $\tau$ hadronic spectral funtion moments strongly sensitive to the GC OPE corrections is considerably improved. We show that these improvements may lead to higher precision for strong coupling determinations.

   hep-phPoS(2022)·1 citation
7. 07*

   Flavour anomalies meet flavour symmetry

   Innes Bigaran🇦🇺 · Tobias Felkl🇦🇺 · Claudia Hagedorn🇪🇸 · Michael A. Schmidt🇦🇺

   We construct an extension of the Standard Model with a scalar leptoquark $\varphi \sim (3,1,-\frac{1}{3})$ and the discrete flavour symmetry $G_f=D_{17}\times Z_{17}$ to explain anomalies observed in charged-current semi-leptonic $B$ meson decays and in the muon anomalous magnetic moment, together with the charged fermion masses and quark mixing. The symmetry $Z_{17}^{\mathrm{diag}}$, contained in $G_f$, remains preserved by the leptoquark couplings, at leading order, and efficiently suppresses couplings of the leptoquark to the first generation of quarks and/or electrons, thus avoiding many stringent experimental bounds. The strongest constraints on the parameter space are imposed by the radiative charged lepton flavour violating decays $\tau \to \mu \gamma$ and $\mu \to e\gamma$. A detailed analytical and numerical study demonstrates the feasibility to simultaneously explain the data on the lepton flavour universality ratios $R(D)$ and $R(D^{\star })$ and the muon anomalous magnetic moment, while passing the experimental bounds from all other considered flavour observables.

   hep-phhep-exPRD(2023)·6 citations
8. 08*

   Is the light neutralino thermal dark matter in the pMSSM ruled out?

   Rahool Kumar Barman🇺🇸 · Geneviève Bélanger🇫🇷 · Biplob Bhattacherjee🇮🇳 · Rohini M. Godbole🇮🇳 · Rhitaja Sengupta🇮🇳

   We explore the parameter space of the phenomenological Minimal Supersymmetric Standard Model (pMSSM) with a light neutralino thermal dark matter ($m_{{\tilde{\chi }}_1^0}\le m_h/2$) that is consistent with current collider and astrophysical constraints. We consider both positive and negative values of the higgsino mass parameter ($\mu$). Our investigation shows that the recent experimental results from the LHC as well as from direct detection searches for dark matter by the LUX-ZEPLIN (LZ) collaboration rule out the $Z$-funnel region for the $\mu >0$ scenario. The same results severely restrict the $h$-funnel region for positive $\mu$, however, the allowed points can be probed easily with few more days of data from the LZ experiment. In the $\mu <0$ scenario, we find that very light higgsinos in both the $Z$ and $h$ funnels might survive the present constraints from the electroweakino searches at the LHC, and dedicated efforts from experimental collaborations are necessary to make conclusive statements about their present status.

   hep-phhep-exPRL(2023)·33 citations
9. 09*

   Gluon dipole factorisation for diffractive dijets

   E. Iancu🇫🇷 · A.H. Mueller🇺🇸 · D.N. Triantafyllopoulos🇮🇹 · S.Y. Wei🇨🇳

   Within the colour dipole picture for deep inelastic scattering at small Bjorken $x$, we study the production of a pair of relatively hard jets via coherent diffraction. By "relatively hard" we mean that the transverse momenta of the two jets -- the quark ($q$) and the antiquark ($\bar{q}$) generated by the decay of the virtual photon -- are much larger than the target saturation momentum $Q_s(Y_{\mathbb{P}})$ evaluated at the rapidity gap $Y_{\mathbb{P}}$. We argue that the typical final-state configurations are such that the hard $q\bar{q}$ dijets are accompanied by a semi-hard gluon jet, with a transverse momentum of the order of $Q_s(Y_{\mathbb{P}})$. The presence of this third jet ensures that the scattering is strong and thus avoids the strong suppression of exclusive (hard) dijet production due to colour transparency. For such "2+1" jet configurations, we demonstrate that both the emission of the semi-hard gluon and its scattering with the hadronic target can be factorised in terms of an effective gluon-gluon dipole. This effective description, originally proposed in [1-4], builds a bridge between the colour dipole picture and collinear factorisation: the cross-section for diffractive 2+1 jets can be written as the product between a hard factor describing the $q\bar{q}$ dijets and a semi-hard factor expressing the unintegrated gluon distribution of the Pomeron. The latter is controlled by gluon dipole scattering in the black disk limit and hence is strongly sensitive to gluon saturation. By integrating out the kinematics of the 3 jets, we obtain the $q\bar{q}g$ contribution to the diffractive structure function in collinearly-factorised form.

   hep-phhep-exnucl-thJHEP(2022)·42 citations
10. 10*

    Scale-invariant 3-3-1-1 model with $B-L$ symmetry

    Alex G. Dias🇧🇷 · Julio Leite🇧🇷 · B. L. Sánchez-Vega🇧🇷

    Motivated by a possible interplay between the mechanism of dynamical symmetry breaking and the seesaw mechanism for generating fermion masses, we present a scale-invariant model that extends the gauge symmetry of the Standard Model electroweak sector to SU(3)${}_L\otimes$U(1)${}_X\otimes$U(1)${}_N$, with a built-in $B-L$ symmetry. The model is based on the symmetry structure of the known 3-3-1 models and, thus, it relates the number of the three observed fermion generations with the cancellation of gauge anomalies. Symmetry breaking is triggered via the Coleman-Weinberg mechanism taking into account a minimal set of scalar field multiplets. We establish the stability conditions for the tree-level scalar potential imposing the copositivity criteria and use the method of Gildener-Weinberg for computing the one-loop effective potential when one has multiple scalar fields. With the addition of vectorial fermions, getting their mass mainly through the vacuum expectation value of scalar singlets at $10^3$ TeV, the $B-L$ symmetry leads to textures for the fermion mass matrices, allowing seesaw mechanisms for neutrinos and quarks to take place. In particular, these mechanisms could partly explain the mass hierarchies of the quarks. Once the breakdown of the SU(3)${}_L$ symmetry is supposed to occur around 10 TeV, the model also predicts new particles with TeV-scale masses, such as a neutral scalar, $H_1$, a charged scalar, $H^{\pm }$, and the gauge bosons $Z^{\prime }$, $W^{\prime \pm }$ and $Y^0$, that could be searched with the high-luminosity LHC.

    hep-phPRD(2022)·9 citations
11. 11*

    Modeling early-universe energy injection with Dense Neural Networks

    Yitian Sun🇺🇸 · Tracy R. Slatyer🇺🇸

    We show that Dense Neural Networks can be used to accurately model the cooling of high-energy particles in the early universe, in the context of the public code package DarkHistory. DarkHistory self-consistently computes the temperature and ionization history of the early universe in the presence of exotic energy injections, such as might arise from the annihilation or decay of dark matter. The original version of DarkHistory uses large pre-computed transfer function tables to evolve photon and electron spectra in redshift steps, which require a significant amount of memory and storage space. We present a light version of DarkHistory that makes use of simple Dense Neural Networks to store and interpolate the transfer functions, which performs well on small computers without heavy memory or storage usage. This method anticipates future expansion with additional parametric dependence in the transfer functions without requiring exponentially larger data tables.

    hep-phastro-ph.COastro-ph.HEPRD(2023)·7 citations
12. 12*

    Dark matter from primordial black holes would hold charge

    Ignacio J. Araya🇨🇱 · Nelson D. Padilla🇦🇷 · Marcelo E. Rubio🇮🇹 · Joaquín Sureda🇪🇸 · Juan Magaña🇨🇱 · Loreto Osorio🇨🇱

    We explore the possibility that primordial black holes (PBHs) contain electric charge down to the present day. We find that PBHs should hold a non-zero net charge at their formation, due to either Poisson fluctuations at horizon crossing or high-energy particle collisions. Although initial charge configurations are subject to fast discharge processes through particle accretion or quantum particle emission, we show that maximally rotating PBHs could produce magnetic fields able to shield them from discharge. Moreover, given that electrons are the lightest and fastest charge carriers, we show that the plasma within virialised dark matter haloes can endow PBHs with net negative charge. We report charge-to-mass ratios between $10^{-31}C/\text{mbox}kg$ and $10^{-15}C/\text{mbox}kg$ for PBHs within the mass windows that allow them to constitute the entirety of the dark matter in the Universe.

    ↳ astro-ph.COhep-phJCAP(2023)·23 citations
13. 13*

    Searches for massive neutrinos with mechanical quantum sensors

    Daniel Carney🇺🇸 · Kyle G. Leach🇺🇸 · David C. Moore🇺🇸

    The development of quantum optomechanics now allows mechanical sensors with femtogram masses to be controlled and measured in the quantum regime. If the mechanical element contains isotopes that undergo nuclear decay, measuring the recoil of the sensor following the decay allows reconstruction of the total momentum of all emitted particles, including any neutral particles that may escape detection in traditional detectors. As an example, for weak nuclear decays the momentum of the emitted neutrino can be reconstructed on an event-by-event basis. We present the concept that a single nanometer-scale, optically levitated sensor operated with sensitivity near the standard quantum limit can search for heavy sterile neutrinos in the keV-MeV mass range with sensitivity significantly beyond existing constraints. We also comment on the possibility that mechanical sensors operated well into the quantum regime might ultimately reach the sensitivities required to provide an absolute measurement of the mass of the light neutrino states.

    ↳ hep-exhep-phnucl-exphysics.ins-det+1PRX Quantum(2023)·51 citations
14. 14*

    Radiative stability of tiny cosmological constant from the Swampland and quantized compactification

    Cao H. Nam🇻🇳

    We address a quantization mechanism that can allow us to understand why the cosmological constant is not large under the quantum corrections from studying the circle compactification solution of the Standard Model coupled to Einstein gravity which is subject to the constraint of the Swampland conjectures. A novel result in the present work compared to the previous investigations in the literature is that the radius of the compactified dimension and the 4D cosmological constant ${\Lambda }_4$ must in fact be quantized. The quantization rule of the cosmological constant is given by ${\Lambda }_4\propto n^2$ with $n=1,2,3,4,\dots$, which means that the values of ${\Lambda }_4$ are not arbitrary but only its specific values are allowed. In general, the quantum corrections as well as other effects would break this quantization rule. Hence, it could prevent the quantum fluctuations from generating zero-point energy contributions to the cosmological constant.

    ↳ hep-thgr-qchep-phPRD(2023)·9 citations
15. 15*

    Junction conditions in perfect fluid $f(\mathcal{G},T)$ gravitational theory

    M. Z. Bhatti · Z. Yousaf · M. Yousaf

    This manuscript aims to establish the gravitational junction conditions(JCs) for the $f(\mathcal{G},T)$ gravity. In this gravitational theory, $f$ is an arbitrary function of Gauss-Bonnet invariant $\mathcal{G}$ and the trace of the energy-momentum tensor $T_{\mu \nu }$ i.e., $T$. We start by introducing this gravity theory in its usual geometrical representation and posteriorly obtain a dynamically equivalent scalar-tensor demonstration on which the arbitrary dependence on the generic function $f$ in both $\mathcal{G}$ and $T$ is exchanged by two scalar fields and scalar potential. We then derive the JCs for matching between two different space-times across a separation hyper-surface $\Sigma$, assuming the matter sector to be described by an isotropic perfect fluid configuration. We take the general approach assuming the possibility of a thin-shell arising at $\Sigma$ between the two space-times. However, our results establish that, for the distribution formalism to be well-defined, thin-shells are not allowed to emerge in the general version of this theory. We thus obtain instead a complete set of JCs for a smooth matching at $\Sigma$ under the same conditions. The same results are then obtained in the scalar-tensor representation of the theory, thus emphasizing the equivalence between these two representations. Our results significantly constrain the possibility of developing models for alternative compact structures supported by thin-shells in $f(\mathcal{G},T)$ gravity, e.g. gravastars and thin-shell wormholes, but provide a suitable framework for the search of models presenting a smooth matching at their surface, from which perfect fluid stars are possible examples.

    ↳ gr-qcastro-ph.COhep-phhep-th2 citations
16. 16*

    Seeking for resonances in unitarized one-loop graviton-graviton scattering

    Rafael L. Delgado🇪🇸 · Antonio Dobado🇪🇸 · Domènec Espriu🇪🇸

    Some effective field theories exhibit dynamical resonances that, when properly included, mitigate their bad behaviour at high energies. Unitarization of the partial wave amplitudes is the preferred method to unveil such resonances. Interpreting the Einstein-Hilbert theory in the spirit of effective Lagrangians, we implement the Inverse Amplitude Method and unitarize the one-loop level graviton-graviton scattering in pure gravity. Due to the presence of infrared divergences, the analysis requires a careful treatment of the infrared region and the introduction of infrared regulators, carefully selected in order to fulfil perturbative unitarity. No evidence of any graviball is found, in contradiction with a recent study.

    ↳ hep-thgr-qchep-phPRD(2023)·7 citations
17. 17*

    New Signals in Precision Gravity Tests and Beyond

    Quentin G. Bailey🇺🇸 · Jennifer L. James🇺🇸 · Janessa R. Slone🇺🇸

    We review the status of tests of spacetime symmetries with gravity. Recent theoretical and experimental work has involved gravitational wave signals, precision solar-system tests, and sensitive laboratory tests searching for violations of spacetime symmetries. We present some new theoretical results relevant for short-range gravity tests, with features of multiple length scales, and possible large non-Newtonian forces at short distances.

    ↳ gr-qchep-ph1 citation
18. 18*

    Snowmass White Paper: Belle II physics reach and plans for the next decade and beyond

    Latika Aggarwal · Swagato Banerjee🇺🇸 · Sunil Bansal🇮🇳 · Florian Bernlochner🇩🇪 · Michel Bertemes🇦🇹 · Vishal Bhardwaj🇮🇳 · Alexander Bondar🇷🇺 · Thomas E. Browder🇺🇸 · Lu Cao🇩🇪 · Marcello Campajola🇮🇹 · Giulia Casarosa🇮🇹 · Claudia Cecchi🇮🇹 and 65 other authors

    Belle II is an experiment operating at the intensity frontier. Over the next decades, it will record the decay of billions of bottom mesons, charm hadrons, and tau leptons produced in 10 GeV electron-positron collisions at the SuperKEKB high-luminosity collider at KEK. These data, collected in low-background and kinematically known conditions, will allow us to measure hundreds of parameters that test the standard model (SM) and probe for the existence of new particles, at mass scales orders of magnitudes higher than those studied at the energy frontier. We project our sensitivities for measurements that are of primary relevance and where Belle II will be unique or world leading for data corresponding to 1 to 50 ab${}^{-1}$. Belle II will uniquely probe non-SM contributions in sensitive $b\to q\bar{q}s$ decays and charmless $b\to q\bar{q}d(u)$ decays, semileptonic $b\to s\nu \bar{\nu }$ and $s{\tau }^{+}{\tau }^{-}$ decays, fully leptonic $b\to \ell \nu$ decays, and select $c\to u$ processes. Belle II will lead exploration of non-SM physics in $b\to c\tau \nu$ and $b\to s\gamma$ decays and will most precisely determine the quark-mixing parameters $|V_{ub}|$ and $|V_{cb}|$. Belle II will measure many parameters in $\tau$ physics to precisions that will be world leading for the foreseeable future, including the electric and magnetic dipole moments, branching fractions for charged-lepton-flavor-violating decays, and quantities that test lepton-flavor universality. Belle II will perform unique searches for dark-sector particles with masses in the MeV-GeV range. We will also pursue a broad spectroscopy program for conventional and multiquark $c\bar{c}$ and $b\bar{b}$ states and provide essential inputs to sharpen the interpretation of muon magnetic-anomaly results. Our exploration of uncharted regions of non-SM parameter space with high precision will reveal non-SM particles or set stringent constraints on their existence, guiding future endeavors.

    ↳ hep-exhep-ph154 citations
19. 19*

    Search for Lorentz-Invariance Violation with the first KATRIN data

    M. Aker🇩🇪 · D. Batzler🇩🇪 · A. Beglarian🇩🇪 · J. Behrens🇩🇪 · A. Berlev🇷🇺 · U. Besserer🇩🇪 · B. Bieringer🇩🇪 · F. Block🇩🇪 · S. Bobien🇩🇪 · B. Bornschein🇩🇪 · L. Bornschein🇩🇪 · M. Böttcher🇩🇪 and 121 other authors

    Some extensions of the Standard Model of Particle Physics allow for Lorentz invariance and Charge-Parity-Time (CPT)-invariance violations. In the neutrino sector strong constraints have been set by neutrino-oscillation and time-of-flight experiments. However, some Lorentz-invariance-violating parameters are not accessible via these probes. In this work, we focus on the parameters $(a_{\text{of}}^{(3)}{)}_{00}$, $(a_{\text{of}}^{(3)}{)}_{10}$ and $(a_{\text{of}}^{(3)}{)}_{11}$ which would manifest themselves in a non-isotropic beta-decaying source as a sidereal oscillation and an overall shift of the spectral endpoint. Based on the data of the first scientific run of the KATRIN experiment, we set the first limit on $\left|(a_{\text{of}}^{(3)}{)}_{11}\right|$ of $<3.7\cdot 10^{-6}$ GeV at 90\% confidence level. Moreover, we derive new constraints on $(a_{\text{of}}^{(3)}{)}_{00}$ and $(a_{\text{of}}^{(3)}{)}_{10}$.

    ↳ nucl-exhep-exhep-phPRD(2023)·27 citations
20. 20*

    Confining complex ghost degrees of freedom

    Marco Frasca🇮🇹 · Anish Ghoshal🇵🇱 · Alexey S. Koshelev🇵🇹

    We show a theorem proving that a non-local bosonic field upon a covariant interaction with a confining gauge field undergoes the confinement of its degrees of freedom present in the free theory changing completely the physical mass spectrum following Kugo-Ojima criterion. This is applicable to an infinite number of excitations of the bosonic field including ghosts whereas we pay special attention to the modes with the complex conjugate masses, states appearing in the string field theory motivated infinite-derivative models. The same recipe will obviously work for the Lee-Wick models.

    ↳ hep-thgr-qchep-phPLB(2023)·13 citations
21. 21*

    Probing the initial state of inflation: analytical structure of cosmological correlators

    Diptimoy Ghosh🇮🇳 · Amartya Harsh Singh🇮🇳 · Farman Ullah🇮🇳

    We study the analytic structure of in-in correlation functions in a deSitter background. The aim of this study is to probe the initial conditions for inflation through the features of correlation functions of the field fluctuations, and understand precisely how an in-in correlator responds to particles in the initial state. We emphasize that the choice of vacuua and the corresponding particle interpretation for these fluctuations is flexible, and we clarify the role of this choice at the level of calculations and their diagrammatic interpretation. We consider several possibilities aside from the standard Bunch Davies vacuum prescription for the initial state, and trace the change in pole structure as one begins adding excitations; starting from just a single particle, to highly excited states and special cases such as a coherent state. We illustrate - with the example of coherent states - the subtleties in concluding a Bunch Davies initial state from the absence of physical poles in the bispectrum, which is interesting in light of some recent literature. Initial states with a finite number of excitations are plagued with disconnected diagrams isolated in phase space, and we highlight their implications on the observation of these signals, and how the situation changes as one begins to excite more and more particles. We also comment about the implications of various initial conditions on the squeezed limit of the bispectrum. These new pole structures are a direct consequence of mixing of positive and negative frequency modes which is a characteristic of curved spacetimes; in particular, we see in detail how particles in an initial state replicate mode mixing structures. This study aims to clarify the missing details that link quantum and classical initial conditions, and sharpen our understanding of in-in correlators in inflation.

    ↳ hep-thgr-qchep-phJCAP(2023)·28 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.