Tue·Apr 6, 2021Tuesday·April 6, 2021

1. 01*

   New $X_{0,1}(2900)$-like exotic states in $b$-baryon decays

   Yu-Kuo Hsiao🇨🇳 · Yao Yu🇨🇳

   In the $B^{+}\to D^{+}{D}^{-}{K}^{+}$ decay, LHCb has reported the observation of the open-charm exotic states $X_{0,1}^0\equiv X_{0,1}(2900{)}^0$ with four different quark flavors~$(ud\bar{s}\bar{c})$, where the subscripts (0,1) denote the spins. To confirm the discovery, we propose ${\Lambda }_b\to {\Sigma }_c^{0(++)}{X}_{0,1}^{\prime 0(--)}$ in the final state interaction, where $X_{0,1}^{\prime 0(--)}$ with $su\bar{d}\bar{c}$ ($ds\bar{u}\bar{c}$) are the new $X_{0,1}$-like exotic states. More specifically, ${\Lambda }_c^{+}{D}_s^{-}$ in ${\Lambda }_b\to {\Lambda }_c^{+}{D}_s^{-}$ are transformed as ${\Sigma }_c^{0(++)}{X}_{0,1}^{\prime 0(--)}$, by exchanging ${\pi }^{+(-)}$. As the order of magnitude estimates, we calculate $\mathcal{B}({\Lambda }_b\to {\Sigma }_c^{0(++)}{X}_{0,1}^{\prime 0(--)})=(2.3\pm 0.6,4.3\pm 0.8_{-2.5}^{+3.3})\times 10^{-4}$. In addition, we estimate other $b$-baryon decays with the $X_{0,1}$-like states, such as $\mathcal{B}({\Xi }_b^{0(-)}\to {\Xi }_c^{0(+)}(2645)X_0^{\prime 0(--)},{\Lambda }_b\to {\Xi }_c^{\prime 0}{X}_{0,1}^0)\sim 10^{-5}$. While one needs ${\Lambda }_b\to {\Sigma }_c^{0(++)}{M}_{c}M$ to observe $X_{0,1}^{\prime 0(--)}\to M_{c}M$ with $M_{c}M=D_s^{-}{\pi }^{+}$, ${\bar{D}}^0{\bar{K}}^0$ $(D_s^{-}{\pi }^{-}$, $D^{-}{K}^{-})$, $\mathcal{B}({\Lambda }_b\to {\Sigma }_c^{0(++)}{X}_{0,1}^{\prime 0(--)},X_{0,1}^{\prime 0(--)}\to M_{c}M)\sim 10^{-4}$ are accessible to the LHCb experiment.

   hep-phhep-exPRD(2021)·11 citations
2. 02*

   Axion-Sterile-Neutrino Dark Matter

   Alberto Salvio🇮🇹 · Simone Scollo🇮🇹

   Extending the Standard Model with three right-handed neutrinos and a simple QCD axion sector can account for neutrino oscillations, dark matter and baryon asymmetry; at the same time, it solves the strong CP problem, stabilizes the electroweak vacuum and can implement critical Higgs inflation (satisfying all current observational bounds). We perform here a general analysis of dark matter (DM) in such a model, which we call the $a\nu$MSM. Although critical Higgs inflation features a (quasi) inflection point of the inflaton potential we show that DM cannot receive a contribution from primordial black holes in the $a\nu$MSM. This leads to a multicomponent axion-sterile-neutrino DM and allows us to relate the axion parameters, such as the axion decay constant, to the neutrino parameters. We include several DM production mechanisms: the axion production via misalignment and decay of topological defects as well as the sterile-neutrino production through the resonant and non-resonant mechanisms and in the recently proposed CPT-symmetric universe.

   hep-phastro-ph.COhep-thUniverse(2021)·12 citations
3. 03*

   Possible Assignment of Excited Light ${}^3{S}_1$ Vector Mesons

   Jie-Cheng Feng🇨🇳 · Xian-Wei Kang🇨🇳 · Qi-Fang Lü🇨🇳 · Feng-Shou Zhang🇨🇳

   We reanalyze the problems in the assignment of 3${}^3{S}_1$ and 4${}^3{S}_1$ light mesons, which have not yet been well established with the $q\bar{q}$ quark model. Regge trajectories and the ${}^3{P}_0$ decay model are used respectively to study the mass and width of the observed states and predict the missing ones. By comparing our calculations with the latest experiments, we suggest that the inconsistent data of $\rho (2150)$ may include two similar structures $\rho (4^3{S}_1)$ and $\omega (4^3{S}_1)$. In addition, the problem of the $K^{\ast }(2^3{S}_1)$ assignment, with two observed states $K^{\ast }(1410)$ and $K^{\ast }(1680)$, is investigated, with several possible explanations.

   hep-phhep-exnucl-thPRD(2021)·24 citations
4. 04*

   The cross section of the process $e^{+}{e}^{-}\to p\bar{p}$ in the vicinity of charmonium $\psi (3770)$ including three-gluon and $D$-meson loop contributions

   Yu.M. Bystritskiy🇷🇺

   The total cross section of the process $e^{+}{e}^{-}\to p\bar{p}$ is calculated within the energy range close to the mass of $\psi (3770)$ charmonium state. It was shown that the main contribution to this cross section comes from three gluon mechanism which is also responsible of the large phase with respect to the Born amplitude. This phase provides the characteristic dip behaviour of the cross section in contrast to the usual Breit-Wigner peak shape. OZI-allowed mechanism with D-mesons in the intermediate state was also estimated and gives relatively small contribution to the cross section and to the phase.

   hep-phPRD(2021)·7 citations
5. 05*

   Possible nature of Dark Matter

   Wasif Husain🇦🇺 · Anthony W. Thomas🇦🇺

   {We present a study of neutron star models that contain dark matter (DM) in the core. The DM is assumed to have a particle nature and to be self-interacting. Using constraints on the mass and radius of neutron stars, we investigate the allowed properties of either bosonic or fermionic DM particles. We consider cases where it constitutes up to 15\% of the mass of the star, even though conventional mechanisms cannot generate such large fractions. For this purpose three different models of neutron stars are considered, the first involving nucleons only, the second including hyperons, and the last involving strange matter in the core. Different EoSs are constructed for the various cases of fermionic and bosonic DM. These EoSs are solved for selected properties of the DM particles and the results are tested against mass, radius and tidal deformability constraints for neutron stars. The distribution of energy density of DM and ordinary matter inside the neutron stars is also presented. It is found that if the DM is fermionic in nature it does not just sit in the core but it is present everywhere in the star, from the centre to outside the surface and may even envelop it.

   hep-phastro-ph.COastro-ph.GAastro-ph.HE+1JCAP(2021)·16 citations
6. 06*

   Factorization of radiative leptonic D-meson decay with sub-leading power corrections

   Long-Sheng Lu🇨🇳

   In this work, we calculate the sub-leading power contributions to the radiative leptonic $D\to \gamma \ell \nu$ decay. For the first time, we provide the analytic expressions of next-to-leading power contributions and the error estimation associated with the power expansion of $\mathcal{O}({\Lambda }_{\mathrm{QCD}}/m_c)$. In our calculation, we adopt two different models of the $D$-meson distribution amplitudes ${\varphi }_{D,\mathrm{I}}^{+}$ and ${\varphi }_{D,\mathrm{II}}^{+}$. Within the framework of the QCD factorization as well as the dispersion relation, we evaluate the soft contribution up to the next-to-leading logarithmic accuracy, and the higher-twist contribution from the two-particle and three-particle distribution amplitudes is also considered. Finally, we find that all the sub-leading power contributions are significant at ${\lambda }_D({\mu }_0)=354\mathrm{MeV}$, and the next-to-leading power contributions will lead to $143\%$ in ${\varphi }_{D,\mathrm{I}}^{+}$ and $120\%$ in ${\varphi }_{D,\mathrm{II}}^{+}$ corrections to leading power vector form factors with $E_{\gamma }=0.5\mathrm{GeV}$. As the corrections from the higher-twist and local sub-leading power contributions will be enhanced with the growing of the inverse moment, it is difficult to extract an appropriate inverse moment of the $D$-meson distribution amplitude. The predicted branching fractions are $(1.88_{-0.29}^{+0.36})\times 10^{-5}$ for ${\varphi }_{D,\mathrm{I}}^{+}$ and $(2.31_{-0.54}^{+0.65})\times 10^{-5}$ for ${\varphi }_{D,\mathrm{II}}^{+}$, respectively.

   hep-phCPC(2021)·10 citations
7. 07*

   General structure of a gauge boson propagator and pressure of deconfined QCD matter in a weakly magnetized medium

   Bithika Karmakar🇮🇳 · Aritra Bandyopadhyay🇧🇷 · Najmul Haque🇮🇳 · Munshi G Mustafa🇮🇳

   We have systematically constructed the general structure of the gauge boson self-energy and the effective propagator in presence of a nontrivial background like hot magnetized material medium. Based on this as well as the general structure of fermion propagator in weakly magnetized medium we have calculated pressure of deconfined QCD matter within HTL approximation.

   hep-phSpringer Proc.Phys.(2021)·0 citations
8. 08*

   Study of the $Y(4660)$ from a light-quark perspective

   Yun-Hua Chen🇨🇳

   In this paper, we try to reveal the structure of the $Y(4660)$ from the light-quark perspective. We study the dipion invariant mass spectrum and the helicity angular distributions of the $e^{+}{e}^{-}\to Y(4660)\to \psi (2S){\pi }^{+}{\pi }^{-}$ process. In particular, we consider the effects of different light-quark SU(3) eigenstates inside the $Y(4660)$. The strong pion-pion final-state interactions as well as the $K\bar{K}$ coupled channel in the $S$-wave are taken into account model independently by using dispersion theory. We find that the light-quark SU(3) octet state plays a significant role in this transition, implying that the $Y(4660)$ contains a large light-quark component and thus might not be a pure conventional charmonium state. In the fit scheme considering both the SU(3) singlet and SU(3) octet states, two solutions are found, and both solutions reproduce the $\pi \pi$ invariant mass spectra well. New measurement data with higher statistics in the future will be helpful to better distinguish these two solutions.

   hep-phhep-exPRD(2021)·3 citations
9. 09*

   The implication of $J/\psi \to (\gamma +)\mathrm{invisible}$ for the effective field theories of neutrino and dark matter

   Tong Li🇨🇳 · Xiao-Dong Ma🇨🇳 · Michael A. Schmidt🇦🇺 · Rui-Jia Zhang🇨🇳

   We study the implication of $J/\psi$ decay into invisible particles for light sterile neutrino and sub-GeV dark matter (DM). The low-energy effective field theories (EFTs) are used for the description of general neutrino interactions and the Dirac fermion DM coupled to charm quark. For $J/\psi \to \gamma +\mathrm{invisible}$, we perform the likelihood fits for the individual neutrino and DM operators with distinct Lorentz structures and photon spectra. The limits on the decay branching fractions are obtained for different neutrino or DM scenarios and then converted to the lower bounds on the new energy scales. The most stringent bounds on the energy scale in neutrino and DM EFTs are 12.8 GeV and 11.6 GeV, respectively. The purely invisible decay $J/\psi \to \mathrm{invisible}$ provides complementary constraints on the effective operators. The relevant bound on the energy scale is above 100 GeV for the dipole operators. We also evaluate the limit on the DM-nucleon scattering cross section converted from $J/\psi$ data. The data of $J/\psi$ invisible decays are sensitive to the light DM mass range where the DM direct detection experiments cannot probe yet. The future Super Tau Charm Factory after one year run can push the limits down by two orders of magnitude.

   hep-phPRD(2021)·10 citations
10. 10*

    Effective Theories with Dark Matter Applications

    Subhaditya Bhattacharya (IIT Guwahati)🇮🇳 · Jose Wudka (UC Riverside)🇺🇸

    Standard Model (SM) of particle physics has achieved enormous success in describing the interactions among the known fundamental constituents of nature, yet it fails to describe phenomena for which there is very strong experimental evidence, such as the existence of dark matter, and which point to the existence of new physics not included in that model; beyond its existence, experimental data, however, have not provided clear indications as to the nature of that new physics. The effective field theory (EFT) approach, the subject of this review, is designed for this type of situations; it provides a consistent and unbiased framework within which to study new physics effects whose existence is expected but whose detailed nature is known very imperfectly. We will provide a description of this approach together with a discussion of some of its basic theoretical aspects. We then consider applications to high-energy phenomenology and conclude with a discussion of the application of EFT techniques to the study of dark matter physics and it possible interactions with the SM. In several of the applications we also briefly discuss specific models that are ultraviolet complete and may realize the effects described by the EFT.

    hep-phInt.J.Mod.Phys.D(2021)·22 citations
11. 11*

    Coherent neutrino scattering and the Migdal effect on the quenching factor

    Jiajun Liao🇨🇳 · Hongkai Liu🇺🇸 · Danny Marfatia🇺🇸

    Recent measurements of the germanium quenching factor deviate significantly from the predictions of the standard Lindhard model for nuclear recoil energies below a keV. This departure may be explained by the Migdal effect in neutron scattering on germanium. We show that the Migdal effect on the quenching factor can mimic the signal of a light Z' or light scalar mediator in coherent elastic neutrino nucleus scattering experiments with reactor antineutrinos. It is imperative that the quenching factor of nuclei with low recoil energy thresholds be precisely measured close to threshold to avoid such confusion. This will also help in experimental searches of light dark matter.

    hep-phhep-exnucl-exnucl-thPRD(2021)·25 citations
12. 12*

    Large $(g-2{)}_{\mu }$ and signals of decays $e_b\to e_a\gamma$ in a 3-3-1 model with inverse seesaw neutrinos

    L. T. Hue🇻🇳 · H. T. Hung🇻🇳 · N. T. Tham🇻🇳 · H. N. Long🇻🇳 · T.Phong Nguyen🇻🇳

    We show that under current experimental bound of the decays $e_a\to e_b\gamma$, the recent experimental data of the muon anomalous magnetic dipole moment $(g-2{)}_{\mu }$ can be explained in the framework of the 3-3-1 model with right handed neutrinos. In addition, all of these branching ratios can reach closely the recent experimental upper bounds.

    hep-phPRD(2021)·19 citations
13. 13*

    Hunting for QCD Instantons at the LHC in Events with Large Rapidity Gaps

    V.A. Khoze🇬🇧 · V.V. Khoze🇬🇧 · D.L. Milne🇬🇧 · M.G. Ryskin🇷🇺

    We outline a strategy of how to search for QCD instantons of invariant mass 20 -- 60 GeV in diffractive events in low luminosity runs at the LHC. We show that by imposing appropriate selection criteria on the final states, one can select the kinematic regime where the instanton signal exceeds the background by a factor of at least 8. In spite of the relatively strong cuts that we impose on the total transverse energy and the number of charged tracks, ${\sum }_i{E}_{T,i}>15$ GeV, $N_{\mathrm{ch}}>20$ measured within the $0<\eta <2$ interval and excluding events with high $p_T$ particles, the expected cross-section is sufficiently large to study the instanton production in the events with Large Rapidity Gaps at low luminosities, thus avoiding problems with pile-up. The paper also includes an updated computation of instanton cross-sections and other parameters relevant for the ongoing studies.

    hep-phhep-exhep-thPRD(2021)·13 citations
14. 14*

    Radiative Interactions between New Non-Abelian Gauge Sector and the Standard Model

    Takaaki Nomura🇨🇳 · Hiroshi Okada🇰🇷

    We discuss one loop generation of the term connecting gauge fields from a local hidden $SU(2{)}_H$ and the standard model $U(1{)}_Y$ introducing an $SU(2{)}_H$ doublet fermion with non-zero hypercharge and a scalar field in adjoint representation. Then we obtain a kinetic mixing term between $SU(2{)}_H$ and $U(1{)}_Y$ gauge fields after the adjoint scalar field developing vacuum expectation value. We illustrate such a concrete scenario introducing a dark matter model in an ultraviolet (UV) completion with local $SU(2{)}_H$ symmetry where the scalar doublet is our dark matter candidate and its stability is guaranteed by remnant $Z_2$ symmetry from $SU(2{)}_H$. Relic density of dark matter is calculated focusing on the case in which dark matter annihilate into known particles via $SU(2{)}_H$ gauge interactions with radiatively induced kinetic mixing.

    hep-phPLB(2021)·6 citations
15. 15*

    First Saturation Correction in High Energy Proton-Nucleus Collisions: II. Single Inclusive Semi-Hard Gluon Production

    Ming Li🇺🇸 · Vladimir V. Skokov🇺🇸

    Exploiting recently obtained analytic solutions of classical Yang-Mills equations for higher order perturbations in the field of the dilute object (proton), we derive the complete first saturation correction to the single inclusive semi-hard gluon production in high energy proton-nucleus collisions by applying the Lehmann-Symanzik-Zimmermann reduction formula. We thus finalize the program started by Balitsky (see Ref.~\cite{Balitsky:2004rr}) and independently by Chirilli, Kovchegov and Wertepny (see Ref.~\cite{Chirilli:2015tea}) albeit using a very different approach to carry out our calculations. We extracted the functional dependence of gluon spectrum on the color charge densities of the colliding objects; thus our results can be used to evaluate complete first saturation correction to the double/multiple inclusive gluon productions.

    hep-phnucl-thJHEP(2021)·14 citations
16. 16*

    Spectral Clustering for Jet Physics

    G. Cerro (1)🇬🇧 · S. Dasmahapatra (1)🇬🇧 · H.A. Day-Hall (1, 2 and 3)🇬🇧 · B. Ford (1)🇬🇧 · S. Moretti (1)🇬🇧 · C.H. Shepherd-Themistocleous (2) ((1) University of Southampton, UK, (2) Rutherford Appleton laboratory, UK, (3) Czech Technical University, Prague)🇬🇧

    We present a new approach to jet definition alternative to clustering methods, such as the anti-$k_T$ scheme, that exploit kinematic data directly. Instead the new method uses kinematic information to represent the particles in a multidimensional space, as in spectral clustering. After confirming its Infra-Red (IR) safety, we compare its performance in analysing $qq\to H_{125\text{GeV}}\to H_{40\text{GeV}}{H}_{40\text{GeV}}\to b\bar{b}b\bar{b}$, $qq\to H_{500\text{GeV}}\to H_{125\text{GeV}}{H}_{125\text{GeV}}\to b\bar{b}b\bar{b}$ and $gg,q\bar{q}\to t\bar{t}\to b\bar{b}{W}^{+}{W}^{-}\to b\bar{b}jj\ell {\nu }_{\ell }$ events from Monte Carlo (MC) samples, specifically, in reconstructing the relevant final states, to that of the anti-kT algorithm. Finally, we show that the results for spectral clustering are obtained without any change in the parameter settings of the algorithm, unlike the anti-kT case, which requires the cone size to be adjusted to the physics process under study.

    hep-phhep-exJHEP(2022)·8 citations
17. 17*

    Anisotropic pressure and quark number susceptibility of strongly magnetized QCD medium

    Bithika Karmakar🇮🇳 · Ritesh Ghosh🇮🇳 · Aritra Bandyopadhyay🇨🇳 · Najmul Haque🇮🇳 · Munshi G Mustafa🇮🇳

    In this work, we compute the hard thermal loop pressure of quark-gluon plasma within strong magnetic field approximation at one-loop order. Magnetic field breaks the rotational symmetry of the system. As a result, the pressure of QGP becomes anisotropic and one finds two different pressures along the longitudinal (along the magnetic field direction) and transverse direction. Similarly, the second-order quark number susceptibility, which represents the fluctuation of the net quark number density, also becomes anisotropic. We compute the second order QNS of deconfined QCD matter in strong field approximation considering same chemical potential for two quark flavors.

    hep-phSpringer Proc.Phys.(2022)·1 citation
18. 18*

    Cosmic Strings, Inflation, and Gravity Waves

    George Lazarides🇬🇷 · Rinku Maji🇮🇳 · Qaisar Shafi🇺🇸

    We investigate the impact of Coleman-Weinberg inflation on the stochastic gravity wave background spectrum emitted by intermediate scale cosmic strings. The string network is partially inflated and re-enters the horizon at later times after the end of inflation, such that the short string loops are not produced. This leads to a significant modification of the gravity wave spectrum that we explore in detail. We find that Coleman-Weinberg inflation can help to satisfy the Parkes Pulsar Timing Array (PPTA) bound for dimensionless string tension values in the range $G\mu >1.1\times 10^{-10}$. We also identify the modified gravity wave spectra which, in the case of inflation, are compatible with the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) data. We then discuss the formation of monopoles and strings at the same breaking scale and the compatibility of the Monopole, Astrophysics and Cosmic Ray Observatory (MACRO) bound with the PPTA bound, and also with the NANOGrav data. Finally, an example of a realistic non-supersymmetric $E_6$ model incorporating successful Coleman-Weinberg inflation is presented in which monopoles and strings both survive inflation and are present at an observable level.

    hep-phastro-ph.COPRD(2021)·46 citations
19. 19*

    Imprint of the seesaw mechanism on feebly interacting dark matter and the baryon asymmetry

    Arghyajit Datta🇮🇳 · Rishav Roshan🇮🇳 · Arunansu Sil🇮🇳

    We show that the type-I seesaw, responsible for generating the light neutrino mass, itself is capable of accommodating one of the three right handed neutrinos as a freeze-in type of dark matter (DM) where the required smallness of the associated coupling is connected to the lightness of the (smallest) active neutrino mass. It turns out that (a) the non-thermal production of DM having mass $\lesssim \mathcal{O}(1)$ MeV (via decays of $W,Z$ bosons and SM Higgs) consistent with relic density as well as (b) its stability determine this smallest active neutrino mass uniquely $\sim \mathcal{O}(10^{-12})$ eV. On the other hand, the study of flavor leptogenesis in this scenario (taking into account the latest neutrino data and Higgs vacuum stability issue) fixes the scale of two other right handed neutrinos.

    hep-phPRL(2021)·76 citations
20. 20*

    The Structure of the Oscillon: The Dynamics of Attractive Self-Interaction

    David Cyncynates🇺🇸 · Tudor Giurgica-Tiron🇺🇸

    Real scalar fields with attractive self-interaction may form self-bound states, called oscillons. These dense objects are ubiquitous in leading theories of dark matter and inflation; of particular interest are long-lived oscillons which survive past $14$ Gyr, offering dramatic astrophysical signatures into the present day. We introduce a new formalism for computing the properties of oscillons with improved accuracy, which we apply to study the internal structure of oscillons and to identify the physical mechanisms responsible for oscillon longevity. In particular, we show how imposing realistic boundary conditions naturally selects a near-minimally radiating solution, and how oscillon longevity arises from its geometry. Further, we introduce a natural vocabulary for the issue of oscillon stability, which we use to predict new features in oscillon evolution. This framework allows for new efficient algorithms, which we use to address questions of whether and to what extent long-lived oscillons are fine-tuned. Finally, we construct a family of potentials supporting ultra-long-lived oscillons, with lifetimes in excess of $10^{17}$ years.

    hep-phastro-ph.COhep-thnlin.PSPRD(2021)·43 citations
21. 21*

    Phenomenology of a Fake Inert Doublet Model

    Damiano Anselmi🇮🇹 · Kristjan Kannike🇪🇪 · Carlo Marzo🇪🇪 · Luca Marzola🇪🇪 · Aurora Melis🇪🇪 · Kristjan Müürsepp🇪🇪 · Marco Piva🇪🇪 · Martti Raidal🇪🇪

    We introduce a new way of modeling the physics beyond the Standard Model by considering fake, strictly off-shell degrees of freedom: the fakeons. To demonstrate the approach and exemplify its reach, we re-analyze the phenomenology of the Inert Doublet Model under the assumption that the second doublet is a fakeon. Remarkably, the fake doublet avoids the most stringent $Z$-pole constraints regardless of the chosen mass scale, thereby allowing for the presence of new effects well below the electroweak scale. Furthermore, the absence of on-shell propagation prevents fakeons from inducing missing energy signatures in collider experiments. The distinguishing features of the model appear at the loop level, where fakeons modify the Higgs boson $h\to \gamma \gamma$ decay width and the Higgs trilinear coupling. The running of Standard Model parameters proceeds as in the usual Inert Doublet Model case. Therefore, the fake doublet can also ensure the stability of the Standard Model vacuum. Our work shows that fakeons are a valid alternative to the usual tools of particle physics model building, with the potential to shape a new paradigm, where the significance of the existing experimental constraints towards new physics must necessarily be reconsidered.

    hep-phhep-exJHEP(2021)·12 citations
22. 22*

    Direct Detection of Mirror Matter in Twin Higgs Models

    Zackaria Chacko🇺🇸 · David Curtin🇨🇦 · Michael Geller🇮🇱 · Yuhsin Tsai🇺🇸

    We explore the possibility of discovering the mirror baryons and electrons of the Mirror Twin Higgs model in direct detection experiments, in a scenario in which these particles constitute a subcomponent of the observed DM. We consider a framework in which the mirror fermions are sub-nano-charged, as a consequence of kinetic mixing between the photon and its mirror counterpart. We consider both nuclear recoil and electron recoil experiments. The event rates depend on the fraction of mirror DM that is ionized, and also on its distribution in the galaxy. Since mirror DM is dissipative, at the location of the Earth it may be in the form of a halo or may have collapsed into a disk, depending on the cooling rate. For a given mirror DM abundance we determine the expected event rates in direct detection experiments for the limiting cases of an ionized halo, an ionized disk, an atomic halo and an atomic disk. We find that by taking advantage of the complementarity of the different experiments, it may be possible to establish not just the multi-component nature of mirror dark matter, but also its distribution in the galaxy. In addition, a study of the recoil energies may be able to determine the masses and charges of the constituents of the mirror sector. By showing that the mass and charge of mirror helium are integer multiples of those of mirror hydrogen, these experiments have the potential to distinguish the mirror nature of the theory. We also carefully consider mirror plasma screening effects, showing that the capture of mirror dark matter particles in the Earth has at most a modest effect on direct detection signals.

    hep-phastro-ph.HEhep-exJHEP(2021)·38 citations
23. 23*

    Gravitational Waves and Dark Photon Dark Matter from Axion Rotations

    Raymond T. Co🇺🇸 · Keisuke Harigaya🇺🇸 · Aaron Pierce🇺🇸

    An axion rotating in field space can produce dark photons in the early universe via tachyonic instability. This explosive particle production creates a background of stochastic gravitational waves that may be visible at pulsar timing arrays or other gravitational wave detectors. This scenario provides a novel history for dark photon dark matter. The dark photons may be warm at a level detectable in future 21-cm line surveys. For a consistent cosmology, the radial direction of the complex field containing the axion must be thermalized. We explore a concrete thermalization mechanism in detail and also demonstrate how this setup can be responsible for the generation of the observed baryon asymmetry.

    hep-phastro-ph.COJHEP(2021)·99 citations
24. 24*

    Comparing Weak- and Unsupervised Methods for Resonant Anomaly Detection

    Jack H. Collins🇺🇸 · Pablo Martín-Ramiro🇪🇸 · Benjamin Nachman🇺🇸 · David Shih🇺🇸

    Anomaly detection techniques are growing in importance at the Large Hadron Collider (LHC), motivated by the increasing need to search for new physics in a model-agnostic way. In this work, we provide a detailed comparative study between a well-studied unsupervised method called the autoencoder (AE) and a weakly-supervised approach based on the Classification Without Labels (CWoLa) technique. We examine the ability of the two methods to identify a new physics signal at different cross sections in a fully hadronic resonance search. By construction, the AE classification performance is independent of the amount of injected signal. In contrast, the CWoLa performance improves with increasing signal abundance. When integrating these approaches with a complete background estimate, we find that the two methods have complementary sensitivity. In particular, CWoLa is effective at finding diverse and moderately rare signals while the AE can provide sensitivity to very rare signals, but only with certain topologies. We therefore demonstrate that both techniques are complementary and can be used together for anomaly detection at the LHC.

    hep-phhep-exphysics.data-anstat.MLEPJC(2021)·60 citations
25. 25*

    Hybrid stars can be self-bound

    Li-Qun Su🇨🇳 · Yan Yan🇨🇳 · Cheng-Ming Li🇨🇳 · Yong-Feng Huang🇨🇳 · Hongshi Zong🇨🇳

    Based on the properties of uniform nuclear matter at the nuclear saturation density and basic thermodynamic relations, we first re-study the composition of matter on the surface of normal neutron stars and hybrid stars. It is found that the hybrid stars are composed of uniform hadronic matter on the surface rather than heavy nuclei. Then we use the Walceka model and the self-consistent NJL model to describe the equation of state of low-density hadrons and quark matter at high densities respectively, and the P--interpolation method is employed to connect the equation of state at the extreme densities to study hybrid stars. As a result, we find that the obtained hybrid star mass-radius relation and tidal deformability meet the latest astronomical data. More importantly, we find that the hybrid stars we obtained can be self-bound rather than gravitationally bound, which is completely different from previous related studies.

    ↳ nucl-thhep-phPRD(2021)·6 citations
26. 26*

    Neutrino energy reconstruction from semi-inclusive samples

    R. González-Jiménez🇪🇸 · M. B. Barbaro🇮🇹 · J. A. Caballero🇪🇸 · T. W. Donnelly🇺🇸 · N. Jachowicz🇧🇪 · G. D. Megias🇪🇸 · K. Niewczas🇧🇪 · A. Nikolakopoulos🇧🇪 · J. W. Van Orden🇺🇸 · J. M. Udías🇪🇸

    We study neutrino-nucleus charged-current reactions on finite nuclei for the situation in which an outgoing muon and a proton are detected in coincidence, i.e., we focus on semi-inclusive cross sections. We limit our attention to one-body current interactions (quasielastic scattering) and assess the impact of different nuclear effects in the determination of the neutrino energy. We identify the regions in phase space where the neutrino energy can be reconstructed relatively well, and study whether the cross section in those regions is significant. Our results indicate that it is possible to filter more than 50% of all events according to the muon and proton kinematics, so that for the DUNE and T2K fluxes the neutrino energy can be determined with an uncertainty of less than 1% and 3%, respectively. Furthermore, we find that the reconstructed neutrino energy does not depend strongly on how one treats the final-state interactions and is not much affected by the description of the initial state. On the other hand, the estimations of the uncertainty on the neutrino energy show important sensitivity to the modeling of the initial state.

    ↳ nucl-thhep-exhep-phnucl-exPRC(2022)·35 citations
27. 27*

    Nonvanishing Finite Scalar Mass in Flux Compactification

    Takuya Hirose🇯🇵 · Nobuhito Maru🇯🇵

    We study possibilities to realize a nonvanishing finite Wilson line (WL) scalar mass in flux compactification. Generalizing loop integrals in the quantum correction to WL mass at one-loop, we derive the conditions for the loop integrals and mode sums in one-loop corrections to WL scalar mass to be finite. We further guess and classify the four-point and three-point interaction terms satisfying these conditions. As an illustration, the nonvanishing finite WL scalar mass is explicitly shown in a six dimensional scalar QED by diagrammatic computation and effective potential analysis. This is the first example of finite WL scalar mass in flux compactification.

    ↳ hep-thhep-phJHEP(2021)·10 citations
28. 28*

    Spin(11,3), particles and octonions

    Kirill Krasnov🇬🇧

    The fermionic fields of one generation of the Standard Model, including the Lorentz spinor degrees of freedom, can be identified with components of a single real 64-dimensional semi-spinor representation S of the group Spin(11,3). We describe an octonionic model for Spin(11,3) in which the semi-spinor representation gets identified with S=OxO', where O,O' are the usual and split octonions respectively. It is then well-known that choosing a unit imaginary octonion u in Im(O) equips O with a complex structure J. Similarly, choosing a unit imaginary split octonion u' in Im(O') equips O' with a complex structure J', except that there are now two inequivalent complex structures, one parametrised by a choice of a timelike and the other of a spacelike unit u'. In either case, the identification S=OxO' implies that there are two natural commuting complex structures J, J' on S. Our main new observation is that the subgroup of Spin(11,3) that commutes with both J, J' on S is the direct product Spin(6) x Spin(4) x Spin(1,3) of the Pati-Salam and Lorentz groups, when u' is chosen to be timelike. The splitting of S into eigenspaces of J corresponds to splitting into particles and anti-particles. The splitting of S into eigenspaces of J' corresponds to splitting of Lorentz Dirac spinors into two different chiralities. We also study the simplest possible symmetry breaking scenario with the "Higgs" field taking values in the representation that corresponds to 3-forms in R^{11,3}. We show that this Higgs can be designed to transform as the bi-doublet of the left/right symmetric extension of the SM, and thus breaks Spin(11,3) down to the product of the SM, Lorentz and U(1)_{B-L} groups, with the last one remaining unbroken. This 3-form Higgs field also produces the Dirac mass terms for all the particles.

    ↳ hep-thhep-phJ.Math.Phys.(2022)·18 citations
29. 29*

    A complete set of Lorentz-invariant wave packets and modified uncertainty relation

    Kin-ya Oda🇯🇵 · Juntaro Wada🇯🇵

    We define a set of fully Lorentz-invariant wave packets and show that it spans the corresponding one-particle Hilbert subspace, and hence the whole Fock space as well, with a manifestly Lorentz-invariant completeness relation (resolution of identity). The position-momentum uncertainty relation for this Lorentz-invariant wave packet deviates from the ordinary Heisenberg uncertainty principle, and reduces to it in the non-relativistic limit.

    ↳ hep-thhep-phquant-phEPJC(2021)·9 citations
30. 30*

    Effective field theory for shallow P-wave states

    E. Epelbaum🇩🇪 · J. Gegelia🇩🇪 · H.P. Huesmann🇩🇪 · U.-G. Meißner🇩🇪 · X.-L. Ren🇩🇪

    We discuss the formulation of a non-relativistic effective field theory for two-body P-wave scattering in the presence of shallow states and critically address various approaches to renormalization proposed in the literature. It is demonstrated that the consistent renormalization involving only a finite number of parameters in the well-established formalism with auxiliary dimer fields corresponds to the inclusion of an infinite number of counterterms in the formulation with contact interactions only. We also discuss the implications from the Wilsonian renormalization group analysis of P-wave scattering.

    ↳ nucl-thhep-phhep-thFew Body Syst.(2021)·15 citations
31. 31*

    Manipulating strong electromagnetic fields with the average transverse momentum of relativistic nuclear collisions

    Giuliano Giacalone🇩🇪 · Chun Shen🇺🇸

    We show that an event-shape engineering based on the mean transverse momentum of charged hadrons, $[p_t]$, provides an optimal handle on the strength of the magnetic field created in central heavy-ion collisions at high energy. This is established through quantitative evaluations of the correlation existing between the event-by-event magnetic field produced by the spectator protons in 5.02 TeV Pb+Pb collisions and the event-by-event $[p_t]$ at a given collision centrality. We argue that the event selection based on $[p_t]$ provides a better handle on the magnetic field than the more traditional selection based on the event ellipticities. Advantages brought by this new method for the experimental search of the chiral magnetic effect are discussed.

    ↳ nucl-thhep-exhep-phnucl-exEPJA(2021)·4 citations
32. 32*

    Two-body wave functions and compositeness from scattering amplitudes: II. Application to the physical $N^{\ast }$ and ${\Delta }^{\ast }$ resonances

    Takayasu Sekihara🇯🇵

    The meson-baryon molecular components for the $N^{\ast }$ and ${\Delta }^{\ast }$ resonances are investigated in terms of the compositeness, which is defined as the norm of the two-body wave function from the meson-baryon scattering amplitudes. The scattering amplitudes are constructed in a $\pi N$-$\eta N$-$\sigma N$-$\rho N$-$\pi \Delta$ coupled-channels problem in a meson exchange model together with several bare $N^{\ast }$ and ${\Delta }^{\ast }$ states, and parameters are fitted so as to reproduce the on-shell $\pi N$ partial wave amplitudes up to the center-of-mass energy 1.9 GeV with the orbital angular momentum $L\le 2$. As a result, the Roper resonance $N(1440)$ is found to be dominated by the $\pi N$ and $\sigma N$ molecular components while the bare-state contribution is small. The squared wave functions in coordinate space imply that both in the $\pi N$ and $\sigma N$ channels the separation between the meson and baryon is about more than 1 fm for the $N(1440)$ resonance. On the other hand, dominant meson-baryon molecular components are not observed in any other $N^{\ast }$ and ${\Delta }^{\ast }$ resonances in the present model, although they have some fractions of the meson-baryon clouds.

    ↳ nucl-thhep-exhep-phnucl-exPRC(2021)·10 citations
33. 33*

    Determination of shear forces inside the proton

    V. D. Burkert🇺🇸 · L. Elouadrhiri🇺🇸 · F.X. Girod🇺🇸

    We report on the first determination of the shear forces quarks inside the proton from experimental data on deeply virtual Compton scattering. The maximum shear force of approximately 40 MeV/fm occurs near 0.6 fm from the proton center, indicating where confinement forces may be strongest. On the macroscopic scale of the earth surface, this force corresponds to the weight of a mass of about 650 kg. The shear forces in the proton reverse direction at r = 0.45 fm from the center.

    ↳ nucl-exhep-exhep-lathep-ph+164 citations
34. 34*

    First Analysis of Jupiter in Gamma Rays and a New Search for Dark Matter

    Rebecca K. Leane🇺🇸 · Tim Linden🇸🇪

    We present the first dedicated $\gamma$-ray analysis of Jupiter, using 12 years of data from the Fermi Telescope. We find no robust evidence of $\gamma$-ray emission, and set upper limits of $\sim 10^{-9}$GeV cm${}^{-2}$s${}^{-1}$ on the Jovian $\gamma$-ray flux. We point out that Jupiter is an advantageous dark matter (DM) target due to its large surface area (compared to other solar system planets), and cool core temperature (compared to the Sun). These properties allow Jupiter to both capture and retain lighter DM, providing a complementary probe of sub-GeV DM. We therefore identify and perform a new search for DM-sourced $\gamma$-rays in Jupiter, where DM annihilates to long-lived particles, which can escape the Jovian surface and decay into $\gamma$-rays. We consequently constrain DM-proton scattering cross-sections as low as about $10^{-40}$cm${}^2$, showing Jupiter is up to ten orders of magnitude more sensitive than direct detection. This sensitivity is reached under the assumption that the mediator decay length is sufficient to escape Jupiter, and the equilibrium between DM capture and annihilation; sensitivities can be lower depending on the DM model. Our work motivates follow-up studies with upcoming MeV telescopes such as AMEGO and e-ASTROGAM.

    ↳ astro-ph.HEastro-ph.EPhep-phPRL(2023)·71 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.