Wed·Jun 15, 2022Wednesday·June 15, 2022

1. 01*

   Symmetry in neutrino oscillation in matter with non-unitarity

   Hisakazu Minakata🇺🇸

   Recently we have developed a method called ``Symmetry Finder'' (SF) for hunting the reparametrization symmetry in the three-neutrino system in matter. Here, we apply SF to the Denton {\it et al.} (DMP) perturbation theory extended by including unitarity violation (UV), a possible low-energy manifestation of physics beyond the $\nu$SM. Implementation of UV into the SF framework yields the additional two very different constraints, which nonetheless allow remarkably consistent solutions, the eight DMP-UV symmetries. Treatment of one of the constraints, the genuine non-unitary part, leads to the key identity which entails the UV $\alpha$ parameter transformation only by rephasing, which innovates the invariance proof of the Hamiltonian. The quantum mechanical nature of the symmetry dictates the both $\nu$SM and UV variables to transform jointly, through which the response of the two sectors are related to reveal their interplay. Thus, the symmetry can serve for a tool for diagnostics, probing the interrelation between the $\nu$SM and a low-energy description of new physics. Problem of SF symmetry in vacuum is revisited to complete eight symmetries akin to DMP's.

   hep-phActa Phys.Polon.B(2023)·3 citations
2. 02*

   When quantum corrections alter the predictions of classical field theory for scalar field dark matter

   Andrew Eberhardt🇺🇸 · Michael Kopp🇸🇪 · Tom Abel🇺🇸

   We investigate the timescale on which quantum corrections alter the predictions of classical field theory for scalar field dark matter. This is accomplished by including second order terms in the evolution proportional to the covariance of the field operators. When this covariance is no longer small compared to the mean field value, we say that the system has reached the ``quantum breaktime" and the predictions of classical field theory will begin to differ from those of the full quantum theory. While holding the classical field theory evolution fixed, we determine the change of the quantum breaktime as total occupation number is increased. This provides a novel numerical estimation of the breaktime based at high occupations $n_{tot}$ and mode number $N=256$. We study the collapse of a sinusoidal overdensity in a single spatial dimension. We find that the breaktime scales as $\log (n_{tot})$ prior to shell crossing and then then as a powerlaw following the collapse. If we assume that the collapsing phase is representative of halos undergoing nonlinear growth, this implies that the quantum breaktime of typical systems may be as large as $\sim 30$ of dynamical times even at occupations of $n_{tot}\sim 10^{100}$.

   hep-phPRD(2022)·15 citations
3. 03*

   Exclusive ${\pi }^0$ production at EIC of China within handbag approach

   S. V. Goloskokov🇷🇺 · Ya-Ping Xie🇨🇳 · Xurong Chen🇨🇳

   The exclusive ${\pi }^0$ electroproduction is analyzed within the handbag approach based on Generalized Parton Distributions (GPDs) factorization. We consider the leading-twist contribution together with the transversity effects. It is shown that the transversity, $H_T$ and ${\bar{E}}_T$ GPDs are essential in the description of ${\pi }^0$ cross section. Predictions for future Electron-Ion Collider of China (EicC) energy range are done. It is found that transversity dominance ${\sigma }_T\gg {\sigma }_L$, observed at low energies is valid up to EicC energy range.

   hep-phCPC(2022)·9 citations
4. 04*

   Single production of vector-like $T$ quark at future high-energy linear $e^{+}{e}^{-}$ collider

   Lin Han🇨🇳 · Liu-Feng Du🇨🇳 · Yao-Bei Liu🇨🇳

   Based on a model-independent framework including the vector-like top partner (VLQ-$T$), we investigate the prospect of discovering the singlet or doublet VLQ-$T$ via the single production process $e^{-}{e}^{+}\to T\bar{t}+t\bar{T}$ with the $T\to Zt$ decay channel at future high energy linear $e^{+}{e}^{-}$ collider with $\sqrt{s}=3$ TeV. We focus on the hadronic decay of the top quark and two types of decay channel for the $Z$ boson: $Z\to {\ell }^{+}{\ell }^{-}$ and $Z\to \nu \bar{\nu }$. By carrying out a full simulation for the signals and the relevant SM backgrounds, the $2\sigma$ exclusion limit and $5\sigma$ discovery prospects are, respectively, obtained on the VLQ-$T$ mass and the coupling strength $g^{\ast }$ with the integrated luminosity of 5 ab${}^{-1}$. In addition, we considered the initial state radiation and beamstrahlung effects as well as the systematic uncertainty effects of backgrounds, which are found to reduce the excluding or discovery capability.

   hep-phPRD(2022)·12 citations
5. 05*

   Lepton masses and mixings, and muon anomalous magnetic moment in an extended $B-L$ model with type I seesaw mechanism

   V. V. Vien🇻🇳 · H. N. Long🇻🇳 · A. E. Cárcamo Hernández🇨🇱

   We propose a $B-L$ model combined with the $S_4\times Z_3\times Z_4$ discrete symmetry which successfully explains the recent $3+1$ sterile - active neutrino data. The smallness of neutrino mass is obtained through the type-I seesaw mechanism. The active-active and sterile-active neutrino mixing angles are predicted to be consistent with the recent constraints in which $0.3401(0.3402)\le {\sin }^2{\theta }_{12}\le 0.3415(0.3416),0.456(0.433)\le {\sin }^2{\theta }_{23}\le 0.544(0.545),2.00(2.018)\le 10^2\times {\sin }^2{\theta }_{13}\le 2.405(2.424),156(140.8)\le {\delta }_{CP}^{(\circ )}\le 172(167.2)$ for normal (inverted) ordering of the three neutrino scenario, and $0.015(0.022)\le s_{14}^2\le 0.045(0.029),0.005(0.0095)\le s_{24}^2\le 0.012(0.012),0.003(0.009)\le s_{34}^2\le 0.011$ for normal (inverted) ordering of the $3+1$ neutrino scenario. Our model predicts flavour conserving leptonic neutral scalar interactions and successfully explains the muon $g-2$ anomaly.

   hep-phPTEP(2022)·5 citations
6. 06*

   Relations for low-energy coupling constants in baryon chiral perturbation theory derived from the chiral quark model

   Jun Jiang🇨🇳 · Shao-Zhou Jiang🇨🇳 · Shi-Yuan Li🇨🇳 · Yan-Rui Liu🇨🇳 · Zong-Guo Si🇨🇳 · Hong-Qian Wang🇨🇳

   The quark model symmetry can be adopted to establish relations between the low-energy constants (LECs) in the baryon chiral perturbation theory ($\chi PT$) if one assumes that a baryon-baryon-meson coupling is described equivalently by a quark-quark-meson coupling at the quark level. Through the correspondence between the $SU(2)$ description and the $SU(3)$ description for the same coupling vertex at the quark level, we find some relations between the LECs in $SU(2{)}_{\chi PT}$ and $SU(3{)}_{\chi PT}$ up to the third chiral order. The $SU(3{)}_{\chi PT}$ LEC relations at the same order are also obtained. The numerical analysis roughly supports these relations. In the situation that the available experimental data are not enough, one may employ such constraints to reduce the number of LECs.

   hep-phhep-latnucl-thPRD(2022)·4 citations
7. 07*

   Fermionic DIS from a deformed string/gauge correspondence model

   Eduardo Folco Capossoli🇧🇷 · Miguel Angel Martín Contreras🇨🇱 · Danning Li🇨🇳 · Alfredo Vega🇨🇱 · Henrique Boschi-Filho🇧🇷

   From a deformed AdS${}_5$ space, we used the string/gauge duality to study the deep inelastic scattering for unpolarized fermions with spin 1/2, considering the large Bjorken $x$ parameter regime. Here, we also took into account an anomalous dimension of an operator which represents fermions at the boundary. From this analysis, we compute the corresponding structure functions, which are dependent on $x$ and on the photon virtuality $q$. The results achieved are in agreement with the experimental data.

   hep-phhep-thRev.Mex.Fis.Suppl.(2022)·2 citations
8. 08*

   Cosmological Collider Signals of Non-Gaussianity from Higgs boson in GUT

   Nobuhito Maru🇯🇵 · Akira Okawa🇯🇵

   Cosmological Collider Physics gives us the opportunity to probe high-energy physics from observing the spacetime fluctuations generated during inflation imprinted on the cosmic microwave background. In other words, it is a method to investigate physics on energy scales that cannot be reached by terrestrial accelerators by means of precise observations of the universe. In this paper, we focus on the case where the GUT scale is close to the energy scale of inflation, and calculate three point function of inflaton by exchanging the Higgs boson in GUT at tree level. The results are found to be consistent with the current observed restrictions on non-Gaussianity without a drastic fine tuning of parameters, and it might be possible to detect the signature of the Higgs boson in GUT by 21cm spectrum, future LSS and future CMB depending on our model parameters.

   hep-phastro-ph.HEgr-qchep-thInt.J.Mod.Phys.A(2023)·14 citations
9. 09*

   Improved White Dwarves Constraints on Inelastic Dark Matter and Left-Right Symmetric Models

   Anirban Biswas (Sogang U. and CQUeST)🇰🇷 · Arpan Kar (Sogang U. and CQUeST)🇰🇷 · Hyomin Kim (Sogang U. and CQUeST)🇰🇷 · Stefano Scopel (Sogang U. and CQUeST)🇰🇷 · Liliana Velasco-Sevilla (Sogang U., CQUeST and KIAS)🇰🇷

   WIMPs can be captured in compact stars such as white dwarves (WDs) leading to an increase in the star luminosity through their annihilation process. We show that when the WIMP interacts with the nuclear targets within the WD through inelastic scattering and its mass exceeds a few tens GeV the data on low-temperature large-mass WDs in the Messier 4 globular cluster can probe values of the mass splitting $\delta \lesssim$ 40 MeV. Such value largely exceeds those ensuing from direct detection and from solar neutrino searches. We apply such improved constraint to the specific DM scenario of a self-conjugate bi-doublet in the Left-Right Symmetric Model (LRSM), where the standard $SU(2{)}_L$ group with coupling $g_L$ is extended by an additional $SU(2{)}_R$ with coupling $g_R$. We show that bounds from WDs significantly reduce the cosmologically viable parameter space of such scenario, in particular requiring $g_R>g_L$. For instance, for $g_R/g_L$ = 1.8 we find the two viable mass ranges 1.2 TeV $\lesssim m_{\chi }\lesssim$ 3 TeV and 5 TeV $\lesssim m_{\chi }\lesssim$ 10 TeV, when the charged $SU(2{)}_R$ gauge boson mass $M_{W_2}$ is lighter than $\simeq$ 12 TeV. We also discuss the ultraviolet completion of the LRSM model, when the latter is embedded in a Grand Unified Theory. We show that such low-energy parameter space and compatibility to proton-decay bounds require a non-trivial extension of the particle content of the minimal model. We provide a specific example where $M_{W_2}\lesssim$ 10 TeV is achieved by extending the LRSM at high energy with color triplets that are singlets under all other groups, and $g_R/g_L>$1 is obtained by introducing $SU(2{)}_L$ triplets with no $SU(2{)}_R$ counterparts, i.e. by breaking the symmetry between the multiplets of $SU(2{)}_L$ and $SU(2{)}_R$.

   hep-phastro-ph.COPRD(2022)·14 citations
10. 10*

    Resolving an ambiguity of Higgs couplings in the FSM, greatly improving thereby the model's predictive range and prospects

    Jose Bordes (1) · HM Chan (2) · ST Tsou (3) ((1) Departament Fisica Teorica and IFIC, Centro Mixto CSIC-Universitat de Valencia, Calle Moliner 50, E-46100 Burjassot (Valencia), Spain, (2) Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, United Kingdom, (3) Mathematical Institute, University of Oxford, Radcliffe Observatory Quarter, Woodstock Road, Oxford, OX2 6GG, United Kingdom)

    We show that, after resolving what was thought to be an ambiguity in the Higgs coupling, the FSM gives, apart from two extra terms (i) and (ii) to be specified below, an effective action in the standard sector which has the same form as the SM action, the two differing only in the values of the mass and mixing parameters of quarks and leptons which the SM takes as inputs from experiment while the FSM obtains as a result of a fit with a few parameters. Hence, to the accuracy that these two sets of parameters agree in value, and they do to a good extent as shown in earlier work, the FSM should give the same result as the SM in all the circumstances wherethe latter has been successfully applied, except for the noted modifications due to (i) and (ii). If so, it would be a big step forward for the FSM. The correction terms are: (i) a mixing between the SM's $\gamma -Z$ with a new vector boson in the hidden sector, (ii) a mixing between the standard Higgs with a new scalar boson also in the hidden sector. And these have been shown a few years back to lead to (i${}^{\prime }$) an enhancement of the $W$ mass over the SM value \cite{zmixed}, and (ii${}^{\prime }$) effects consistent with the $g-2$ and some other anomalies, precisely the two deviations from the SM reported by experiments \cite{Wmassnew,g-2new} recently much in the news.

    hep-phInt.J.Mod.Phys.A(2022)·3 citations
11. 11*

    Inference of neutrino nature and Majorana CP phases from $0\nu \beta \beta$ decays with inverted mass ordering

    Guo-yuan Huang🇩🇪 · Newton Nath🇮🇹

    Whether the neutrino mass ordering is normal or inverted remains an experimentally open issue in neutrino physics. The knowledge of neutrino mass ordering has great importance for neutrinoless double-beta ($0\nu \beta \beta$) decay experiments, which can establish the nature of massive neutrinos, i.e., whether they are Dirac or Majorana fermions. Recently, the KamLAND-Zen 800 measurement has reached for the first time the parameter space of the inverted ordering with a vanishing lightest neutrino mass. By assuming the inverted ordering, we attempt to derive the physical information of the neutrino nature and Majorana CP phases from a negative or positive observation of $0\nu \beta \beta$ decays in the near future. Moreover, the possibility of extracting the nuclear matrix element in the case of a positive observation is also examined. To avoid the ambiguity from unknown priors of neutrino masses, we adopt the maximum likelihood method instead of the Bayesian approach usually considered in previous works.

    hep-phhep-exEPJC(2022)·3 citations
12. 12*

    Neutrino lines from MeV dark matter annihilation and decay in JUNO

    Kensuke Akita🇰🇷 · Gaetano Lambiase🇮🇹 · Michiru Niibo🇯🇵 · Masahide Yamaguchi🇯🇵

    We discuss the discovery potential of JUNO experiment for neutrino lines from MeV dark matter (DM) annihilation and decay in a model independent way. We find that JUNO will be able to give severe constraints on the cross section of DM annihilating into neutrinos and on the lifetime of DM decaying into neutrinos. More concretely, with $20$ years of data-taking in the fiducial volume $17$ kton, the cross section will be constrained smaller than $4\times 10^{-26}\mathrm{c}{\mathrm{m}}^3\mathrm{se}{\mathrm{c}}^{-1}$ for the mass of a DM particle $15\mathrm{MeV}\lesssim m_{\chi }\lesssim 50\mathrm{MeV}$ at $90\%$ C.L., which might be strong enough to test thermal production mechanism of DM particles for such range of DM mass. The lifetime will be constrained as strong as $1\times 10^{24}\sec$ for the mass of a DM particle $m_{\chi }\simeq 100\mathrm{MeV}$ at $90\%$ C.L..

    hep-phastro-ph.COhep-exJCAP(2022)·24 citations
13. 13*

    A Flavour Inspired Model for Dark Matter

    Claudio Andrea Manzari🇨🇭 · Stefano Profumo🇺🇸

    The discrepancies between data on rare $b$-hadron decays, controlled by the underlying neutral-current transitions $b\to s{\ell }^{+}{\ell }^{-}(\ell =e,\mu )$, and the corresponding Standard Model predictions constitute one of the most intriguing hints for new physics. Leptoquarks are prime candidates to solve these anomalies and, in particular, the scalar leptoquark, $S_3$, triplet under $SU(2{)}_L$ with hypercharge $Y=-1/3$, provides a very good fit to data. Here, for the first time, we entertain the possibility that the same scalar leptoquark, responsible for the LFU anomalies, is the portal to a dark sector consisting of two additional vector-like fermions, one of which is a candidate for the cosmological dark matter. We study two scenarios, where the dark matter candidate belongs to an $SU(2{)}_L$ singlet and triplet respectively, and discuss the theory parameter space in the context of the dark matter candidate's relic density and prospects for direct and indirect dark matter searches. Direct detection rates are highly suppressed, and generically below the neutrino floor. Current observations with, and future prospects for, high-energy gamma-ray telescopes such as HESS and the Cherenkov Telescope Array are much more promising, as they already provide powerful constraints on the models under consideration, and will potentially probe the full parameter space in the future.

    hep-phastro-ph.COastro-ph.HEPRD(2022)·7 citations
14. 14*

    Energy loss in low energy nuclear recoils in dark matter detector materials

    Sebastian Sassi🇫🇮 · Matti Heikinheimo🇫🇮 · Kimmo Tuominen🇫🇮 · Antti Kuronen🇫🇮 · Jesper Byggmästar🇫🇮 · Kai Nordlund🇫🇮 · Nader Mirabolfathi🇺🇸

    Recent progress in phonon-mediated detectors with eV-scale nuclear recoil energy sensitivity requires an understanding of the effect of the crystalline defects on the energy spectrum expected from dark matter or neutrino coherent scattering. We have performed molecular dynamics simulations to determine the amount of energy stored in the lattice defects as a function of the recoil direction and energy. This energy can not be observed in the phonon measurement, thus affecting the observed energy spectrum compared to the underlying true recoil energy spectrum. We describe this effect for multiple commonly used detector materials and demonstrate how the predicted energy spectrum from dark matter scattering is modified.

    hep-phcond-mat.mtrl-sciPRD(2022)·23 citations
15. 15*

    Probing non-standard neutrino interactions with a light boson from next galactic and diffuse supernova neutrinos

    Kensuke Akita🇰🇷 · Sang Hui Im🇰🇷 · Mehedi Masud🇰🇷

    Non-standard neutrino interactions with a massive boson can produce the bosons in the core of core-collapse supernovae (SNe). After the emission of the bosons from the SN core, their subsequent decays into neutrinos can modify the SN neutrino flux. We show future observations of neutrinos from a next galactic SN in Super-Kamiokande (SK) and Hyper-Kamiokande (HK) can probe flavor-universal non-standard neutrino couplings to a light boson, improving the previous limit from the SN 1987A neutrino burst by several orders of magnitude. We also discuss sensitivity of the flavor-universal non-standard neutrino interactions in future observations of diffuse neutrinos from all the past SNe, known as the diffuse supernova neutrino background (DSNB). According to our analysis, observations of the DSNB in HK, JUNO and DUNE experiments can probe such couplings by a factor of $\sim 2$ beyond the SN 1987A constraint. However, our result is also subject to a large uncertainty concerning the precise estimation of the DSNB.

    hep-phastro-ph.COastro-ph.HEhep-exJHEP(2022)·67 citations
16. 16*

    Searching for Afterglow: Light Dark Matter Boosted by Supernova Neutrinos

    Yen-Hsun Lin🇹🇼 · Wen-Hua Wu🇹🇼 · Meng-Ru Wu🇹🇼 · Henry Tsz-King Wong🇹🇼

    A novel analysis is performed, incorporating time-of-flight (TOF) information to study the interactions of dark matter (DM) with standard model particles. After supernova (SN) explosions, DM with mass $m_{\chi }\lesssim \mathcal{O}(\mathrm{MeV})$ in the halo can be boosted by SN neutrinos (SN$\nu$) to relativistic speed. The SN$\nu$ boosted DM (BDM) arrives on Earth with TOF which depends only on $m_{\chi }$ and is independent of the cross section. These BDMs can interact with detector targets in low-background experiments and manifest as afterglow events after the arrival of SN$\nu$. The characteristic TOF spectra of the BDM events can lead to large background suppression and unique determination of $m_{\chi }$. New cross section constraints on $\sqrt{{\sigma }_{\chi e}{\sigma }_{\chi \nu }}$ are derived from SN1987a in the Large Magellanic Cloud with data from the Kamiokande and Super-Kamiokande experiments. Potential sensitivities for the next galactic SN with Hyper-Kamiokande are projected. This analysis extends the existing bounds on $\sqrt{{\sigma }_{\chi e}{\sigma }_{\chi \nu }}$ over a broad range of $r_{\chi }={\sigma }_{\chi \nu }/{\sigma }_{\chi e}$. In particular, the improvement is by 1-3 orders of magnitude for $m_{\chi }<\mathcal{O}(100\mathrm{keV})$ for ${\sigma }_{\chi e}\sim {\sigma }_{\chi \nu }$. Prospects of exploiting TOF information in other astrophysical systems to probe exotic physics with other DM candidates are discussed.

    hep-phastro-ph.HEPRL(2023)·43 citations
17. 17*

    Comparative Study of Magnetic Moment of Leptons in Hot and Dense Media

    Samina Masood🇺🇸 · Holly Mein🇺🇸

    We study the magnetic moment of leptons in extremely hot universe and superdense media of stars at high temperatures. Anomalous magnetic moment of charged leptons is inversely proportional to its mass, whereas, the induced dipole moment of neutral leptons is directly proportional to their mass. Neutral massive point particles exert nonzero magnetic moment as a higher order effect, which is smaller than the anomalous magnetic moment of a charged particle of their same flavor partner. All leptons acquire some extra mass due to their interaction with the medium and affect the magnetic moment accordingly. We compare the contribution to the magnetic moment of various leptons due to their temperature and chemical potential dependent masses. It is shown that the magnetic moment contributions are non-ignorable for lighter leptons and heavy neutrinos. These calculations are very important to study particle propagation in the early universe and in superdense stellar media.

    hep-phastro-ph.HEInt.J.Mod.Phys.A(2022)·1 citation
18. 18*

    A Proposed $E_8\times E_8$ Kinematic Scaffolding for the Standard Model with Pre-Gravitation

    Priyank Kaushik🇮🇳 · Vatsalya Vaibhav🇮🇳 · Tejinder P. Singh🇮🇳

    We present a proposed $E_8\times E_8$ kinematic scaffolding for the standard model with pre-gravitation. The notation $E_8\times \omega E_8$ used below records a split-complex exchange grading of two factors; it is not a tensor product of groups. Each factor branches through $SU(3)\times E_6$ and thence through trinification, $E_6\to SU(3{)}^3$. The first factor supplies representation labels associated with the standard-model lineage, and the second supplies a mirror, pre-gravitational lineage. The identification of a single vector-like colour group across the two factors, and the proposed gravitational reading of the right-sector $SU(2)$, remain dynamical hypotheses. Physical chiral fermions are not assigned to the $E_8$ adjoints: they are modelled by minimal ideals of the complex Clifford algebra $C{l}_6(\mathbb{C})$, while the $496$ adjoint dimensions are used only as a representation-label ledger. The numerical split $208+288$ is therefore a declared roster-matching convention, not an invariant decomposition and not a particle count. Spacetime enters through a selected six-dimensional split-biquaternionic vector space with a separately specified quadratic form of signature $(3,3)$. Its full frame group is $SO(3,3)$; deriving a soldering form and the proposed $BF$/Plebański dynamics remains open. The conventional Clifford--Dirac operator is constructed independently and exactly: $J_2({\mathbb{H}}_s)$ realises the vector space ${\mathbb{R}}^{3,3}$ through its determinant, and after choosing ${\mathbb{H}}_s\cong M_2(\mathbb{R})$ its matrix gradient and adjugate act between real four-dimensional Weyl modules and factorise the wave operator in both orderings. The rank-two algebra supplies the quadratic spacetime layer, whereas $J_3({\mathbb{O}}_{\mathbb{C}})$ supplies the proposed internal, generation and cubic spectral layer through the magic-star decomposition of ${\mathfrak{e}}_8^{\mathbb{C}}$.

    hep-phhep-th29 citations
19. 19*

    On Ambiguity of Definition of Shear and Spin-Hall Contributions to $\Lambda$ Polarization in Heavy-Ion Collisions

    Yu. B. Ivanov🇷🇺 · A. A. Soldatov🇷🇺

    Recently proposed thermal-shear and spin-Hall contributions to the particle polarization in heavy-ion collisions are discussed. Alternative definitions of the thermal-shear contribution, i.e. those of Becattini-Buzzegoli-Palermo on the one hand and Liu-Yin on the other, are very similar in the midrapidity region while quite different at forward-backward rapidities, which are measured in fixed-target experiments. It is shown that the thermal-shear contribution to the global polarization with momentum averaging extended to all momenta is very different within these alternative definitions. The spin-Hall contribution to the global polarization, defined similarly to the Liu-Yin shear one, is identically zero, if averaging runs over all momenta. Only application of restrictive momentum acceptance and the boost (to $\Lambda$ rest frame) correction result in nonzero global spin-Hall polarization. If the spin-Hall contribution were defined similarly to Becattini-Buzzegoli-Palermo shear one, the global spin-Hall polarization would be non-zero even without any acceptance and the boost correction.

    hep-phnucl-thPisma Zh.Eksp.Teor.Fiz.(2022)·6 citations
20. 20*

    Infrared Divergences in $e^{+}{e}^{-}\to 2jets$ in the Light Front Coherent State Formalism

    Deepesh Bhamre🇮🇳 · Anuradha Misra🇮🇳

    We study infrared (IR) divergences in light front quantum chromodynamics using a coherent state basis in light front time-ordered Hamiltonian perturbation theory. In computation of the S-matrix elements in Hamiltonian formalism, the IR divergences appear in the form of vanishing energy denominators. We consider the process $e^{+}{e}^{-}\to 2jets$ at $\mathcal{O}(g^2)$ in strong coupling, construct the coherent state representing the outgoing particles, and explicitly show that the `true' IR divergences cancel to this order when the matrix elements are calculated between coherent states instead of Fock states.

    hep-phhep-thPRD(2023)·2 citations
21. 21*

    The quark quasi Sivers function and quasi Boer-Mulders function in a spectator diquark model

    Chentao Tan🇨🇳 · Zhun Lu🇨🇳

    We compute the leading-twist T-odd quasi-distributions of the proton in a spectator model with scalar and axial-vector diquarks: the quasi Sivers function ${\tilde{f}}_{1T}^{\perp }(x,k_T^2;P_z)$ and the quasi Boer-Mulders function ${\tilde{h}}_1^{\perp }(x,k_T^2;P_z)$. We obtain the quark-quark correlators in the four-dimensional Euclidian space by replacing ${\gamma }^{+}$ and ${\sigma }^{i+}$ in the light-cone frame with ${\gamma }_z$ and ${\sigma }_{iz}$. We show by analytical calculation that the results of ${\tilde{f}}_{1T}^{\perp }$ and ${\tilde{h}}_1^{\perp }$ derived from the correlators can reduce to the expressions of the corresponding standard T-odd distributions $f_{1T}^{\perp }(x,k_T^2)$ and $h_1^{\perp }(x,k_T^2)$ in the limit $P_z\to \infty$. The numerical results for these quasi-distributions and their first transverse moments for the $u$ and $d$ quarks in different $x$ and $P_z$ regions are also presented. We find that ${\tilde{f}}_{1T}^{\perp (1)}(x,P_z)$ and ${\tilde{h}}_1^{\perp (1)}(x,P_z)$ in the spectator model are fair approximations to the standard ones (within 20-30\%) in the region $0.1<x<0.5$ when $P_z\ge 2.5-3$ GeV. This supports the idea of using T-odd quasi-distributions to obtain standard distributions in the region $P_z>2.5$ GeV as fair approximation.

    hep-phPRD(2022)·4 citations
22. 22*

    Asymptotic gluon density within the color dipole picture in the light of HERA high-precision data

    D. A. Fagundes🇧🇷 · M.V.T. Machado🇧🇷

    We present an analysis of the most precise set of HERA data within the color dipole formalism, by using an analytical gluon density, based on the double-logarithm approximation of the DGLAP equations in the asymptotic limit of the scaling variable, $\sigma =\log (1/x)\log (\log (Q^2/Q_0^2))\to \infty$. Fits to data, including charm and bottom quarks are performed and demonstrate the efficiency of the model in describing the reduced cross section, ${\sigma }_r$, in the wide range $Q^2:(1.5,500)$ GeV${}^2$ for two dipole models including parton saturation effects. We also give predictions to $F_2^{c\bar{c}}$ , $F_2^{b\bar{b}}$ and $F_L$, all describing the data reasonably well in the range $Q^2:(2.5,120)$ GeV${}^2$. Total cross sections of exclusive photoproduction of $J/\psi$ and $\rho$ are also calculated and successfully compared to HERA data and recent measurements at LHCb.

    hep-phPRD(2023)·13 citations
23. 23*

    Gravitational Wave Pathway to Testable Leptogenesis

    Arnab Dasgupta🇺🇸 · P.S. Bhupal Dev🇺🇸 · Anish Ghoshal🇵🇱 · Anupam Mazumdar🇳🇱

    We analyze the classically scale-invariant $B-L$ model in the context of resonant leptogenesis with the recently proposed mass-gain mechanism. The $B-L$ symmetry breaking in this scenario is associated with a strong first order phase transition that gives rise to detectable gravitational waves (GWs) via bubble collisions. The same $B-L$ symmetry breaking also gives Majorana mass to right-handed neutrinos inside the bubbles, and their out of equilibrium decays can produce the observed baryon asymmetry of the Universe via leptogenesis. We show that the current LIGO-VIRGO limit on stochastic GW background already excludes part of the $B-L$ parameter space, complementary to the collider searches for heavy $Z^{\prime }$ resonances. Moreover, future GW experiments like Einstein Telescope and Cosmic Explorer can effectively probe the parameter space of leptogenesis over a wide range of the $B-L$ symmetry-breaking scales and gauge coupling values.

    hep-phgr-qcPRD(2022)·94 citations
24. 24*

    Searches for heavy neutrinos at multi-TeV muon collider : a resonant leptogenesis perspective

    Indrani Chakraborty🇮🇳 · Himadri Roy🇮🇳 · Tripurari Srivastava🇮🇳

    In this work, the standard model (SM) is extended with two right-handed (RH) neutrinos and two singlet neutral fermions to yield active neutrino masses via (2,2) inverse see-saw mechanism. We first validate the multi-dimensional model parameter space with neutrino oscillation data, obeying the experimental bounds coming from the lepton flavor violating (LFV) decays: $\mu \to e\gamma ,\tau \to e\gamma ,\tau \to \mu \gamma$. Besides we also search for the portion of the parameter space which yield the observed baryon asymmetry of the universe via resonant leptogenesis. Further, we pick up a few benchmark points from the aforementioned parameter space with TeV scale heavy neutrinos and perform an exhaustive collider analysis of the final states: $2l+\text{mET}$ in multi-TeV muon collider.

    hep-phEPJC(2023)·23 citations
25. 25*

    Axion Couplings in Grand Unified Theories

    Prateek Agrawal🇬🇧 · Michael Nee🇬🇧 · Mario Reig🇬🇧

    We show that the couplings of axions to gauge bosons are highly restricted in Grand Unified Theories where the standard model is embedded in a simple 4D gauge group. The topological nature of these couplings allows them to be matched from the UV to the IR, and the ratio of the anomaly with photons and gluons for any axion is fixed by unification. This implies that there is a single axion, the QCD axion, with an anomalous coupling to photons. Other light axion-like particles can couple to photons by mixing through the QCD axion portal and lie to the right of the QCD line in the mass-coupling plane. Axions which break the unification relation between gluon and photon couplings are necessarily charged under the GUT gauge group and become heavy from perturbative mass contributions. A discovery of an axion to the left of the QCD line can rule out simple Grand Unified models. Axion searches are therefore tabletop and astrophysical probes of Grand Unification.

    hep-phJHEP(2022)·77 citations
26. 26*

    On Codimension-one Vacua and String Theory

    Salvatore Raucci🇮🇹

    We investigate codimension-one vacua arising from low energy effective actions inspired by string theory, with an eye to their consistency when localized sources are allowed in the equations of motion. We draw some inspiration from Sugimoto's USp(32) model, the simplest setting for brane supersymmetry breaking, and from the 0'B model, with their Dudas-Mourad solutions. Although the sources that one can thus identify do not have a clear role in string theory, this type of investigation is naturally suggested by the singularities that appear at the endpoints of internal intervals. We also discuss the introduction of sources in deformed D8-like solutions in type IIA, pointing out an analogy with one of the non-supersymmetric models. Finally, we show that an appropriate choice of frame can simplify computations in models with tadpole potentials.

    ↳ hep-thgr-qchep-phNPB(2022)·26 citations
27. 27*

    Coherent state excitations and string-added coherent states in gauge-gravity correspondence

    Hai Lin🇨🇳

    We analyze detailed properties of BPS coherent states and their connection to gravity. We interpret the group integral coherent state as a path integral over auxiliary variables coupled to the elementary letters of the theory. The eigenvalues of coherent state amplitudes can be viewed as collective coordinates of giant gravitons. Inspired by the above coherent states and by the integrability, we construct a new type of coherent states in the SL(2) sectors and their cousin PSU(1,1|2) sectors, analogous to the aforementioned coherent states. The large spin and small spin limits can be obtained by varying coherent state amplitudes. We add string words onto the BPS coherent states, and this gives rise to string-added coherent states. The insertions of string multi-words can be viewed as operator-insertions in this path integral. We describe BPS states and near BPS states building upon these coherent states in gauge-gravity correspondence. For example, string-added coherent states and their near BPS spectra are analyzed. This approach is particularly convenient for heavy excited states.

    ↳ hep-thgr-qchep-phquant-phNPB(2023)·20 citations
28. 28*

    Nucleon D-term in holographic QCD

    Mitsutoshi Fujita🇨🇳 · Yoshitaka Hatta🇺🇸 · Shigeki Sugimoto🇯🇵 · Takahiro Ueda🇯🇵

    The D-term is one of the conserved charges of hadrons defined as the forward limit of the gravitational form factor $D(t)$. We calculate the nucleon's D-term in a holographic QCD model in which the nucleon is described as a soliton in five dimensions. We show that the form factor $D(t)$ is saturated by the exchanges of infinitely many $0^{++}$ and $2^{++}$ glueballs dual to transverse-traceless metric fluctuations on the Wick rotated AdS${}_7$ black hole geometry. We refer to this phenomenon as `glueball dominance', in perfect analogy to the vector meson dominance of the electromagnetic form factors. However, the value at vanishing momentum transfer $D(t=0)$ can be interpreted as due to the exchange of pairs of pions and infinitely many vector and axial-vector mesons without any reference to glueballs. We find that the D-term is slightly negative as a result of a cancellation between the isovector and isoscalar meson contributions.

    ↳ hep-thhep-phPTEP(2022)·54 citations
29. 29*

    Window observable for the hadronic vacuum polarization contribution to the muon $g-2$ from lattice QCD

    Marco Cè🇨🇭 · Antoine Gérardin🇫🇷 · Georg von Hippel🇩🇪 · Renwick J. Hudspith🇩🇪 · Simon Kuberski🇩🇪 · Harvey B. Meyer🇩🇪 · Kohtaroh Miura🇩🇪 · Daniel Mohler🇩🇪 · Konstantin Ottnad🇩🇪 · Srijit Paul🇩🇪 · Andreas Risch🇩🇪 · Teseo San José🇩🇪 · Hartmut Wittig🇩🇪

    Euclidean time windows in the integral representation of the hadronic vacuum polarization contribution to the muon $g-2$ serve to test the consistency of lattice calculations and may help in tracing the origins of a potential tension between lattice and data-driven evaluations. In this paper, we present results for the intermediate time window observable computed using O($a$) improved Wilson fermions at six values of the lattice spacings below 0.1\,fm and pion masses down to the physical value. Using two different sets of improvement coefficients in the definitions of the local and conserved vector currents, we perform a detailed scaling study which results in a fully controlled extrapolation to the continuum limit without any additional treatment of the data, except for the inclusion of finite-volume corrections. To determine the latter, we use a combination of the method of Hansen and Patella and the Meyer-Lellouch-Lüscher procedure employing the Gounaris-Sakurai parameterization for the pion form factor. We correct our results for isospin-breaking effects via the perturbative expansion of QCD+QED around the isosymmetric theory. Our result at the physical point is $a_{\mu }^{\mathrm{win}}=(237.30\pm 0.79_{\mathrm{stat}}\pm 1.22_{\mathrm{syst}})\times 10^{-10}$, where the systematic error includes an estimate of the uncertainty due to the quenched charm quark in our calculation. Our result displays a tension of 3.9$\sigma$ with a recent evaluation of $a_{\mu }^{\mathrm{win}}$ based on the data-driven method.

    ↳ hep-lathep-phPRD(2022)·321 citations
30. 30*

    Octonion Internal Space Algebra for the Standard Model

    Ivan Todorov🇫🇷

    The paper surveys recent progress in the search for an appropriate internal space algebra for the Standard Model (SM) of particle physics. As a starting point serve Clifford algebras involving operators of left multiplication by octonions. A central role is played by a distinguished complex structure which implements the splitting of the octonions $\mathbb{O}=\mathbb{C}\oplus {\mathbb{C}}^3$ reflecting the lepton-quark symmetry. Such a complex structure in $C{\ell }_{10}$ is generated by the $C{\ell }_6(\subset C{\ell }_8\subset C{\ell }_{10})$ volume form, ${\omega }_6={\gamma }_1\cdots {\gamma }_6$, left invariant by the Pati-Salam subgroup of $Spin(10)$, $G_{\mathrm{PS}}=Spin(4)\times Spin(6)/{\mathbb{Z}}_2$. While the $Spin(10)$ invariant volume form ${\omega }_{10}={\gamma }_1...{\gamma }_{10}$ is known to split the Dirac spinors of $C{\ell }_{10}$ into left and right chiral (semi)spinors, $\mathcal{P}=\frac{1}{2}(1-i{\omega }_6)$ is interpreted as the projector on the 16-dimensional \textit{particle subspace} (annihilating the antiparticles). The standard model gauge group appears as the subgroup of $G_{PS}$ that preserves the sterile neutrino (identified with the Fock vacuum). The ${\mathbb{Z}}_2$-graded internal space algebra $\mathcal{A}$ is then included in the projected tensor product: $\mathcal{A}\subset \mathcal{P}C{\ell }_{10}\mathcal{P}=C{\ell }_4\otimes \mathcal{P}C{\ell }_6^0\mathcal{P}$. The Higgs field appears as the scalar term of a superconnection, an element of the odd part, $C{\ell }_4^1$, of the first factor. The fact that the projection of $C{\ell }_{10}$ only involves the even part $C{\ell }_6^0$ of the second factor guarantees that the colour symmetry remains unbroken. As an application we express the ratio $\frac{m_H}{m_W}$ of the Higgs to the $W$-boson masses in terms of the cosine of the {\it theoretical} Weinberg angle.

    ↳ hep-thhep-phmath-phmath.MPUniverse(2023)·16 citations
31. 31*

    The Dark Dimension, the Swampland, and the Dark Matter Fraction Composed of Primordial Black Holes

    Luis Anchordoqui🇺🇸 · Ignatios Antoniadis🇫🇷 · Dieter Lust🇩🇪

    Very recently, it was suggested that combining the Swampland program with the smallness of the dark energy and confronting these ideas to experiment lead to the prediction of the existence of a single extra-dimension (dubbed the dark dimension) with characteristic length-scale in the micron range. We show that the rate of Hawking radiation slows down for black holes perceiving the dark dimension and discuss the impact of our findings in assessing the dark matter fraction that could be composed of primordial black holes. We demonstrate that for a species scale of $\mathcal{O}(10^{10}\mathrm{GeV})$, an all-dark-matter interpretation in terms of primordial black holes should be feasible for masses in the range $10^{14}\le M_{BH}/\mathrm{g}\le 10^{21}$. This range is extended compared to that in the 4D theory by 3 orders of magnitude in the low mass region. We also show that PBHs with $M_{\mathrm{BH}}\sim 10^{12}\mathrm{g}$ could potentially explain the well-known Galactic 511 keV gamma-ray line if they make up a tiny fraction of the total dark matter density.

    ↳ hep-thastro-ph.COhep-phPRD(2022)·85 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.