Fri·Jun 4, 2021Friday·June 4, 2021

1. 01*

   Dark matter electromagnetic dipoles: the WIMP expectation

   Thomas Hambye🇧🇪 · Xun-Jie Xu🇧🇪

   We perform a systematic study of the electric and magnetic dipole moments of dark matter (DM) that are induced at the one-loop level when DM experiences four-fermion interactions with Standard Model (SM) charged fermions. Related to their loop nature these moments can largely depend on the UV completion at the origin of the four-fermion operators. We illustrate this property by considering explicitly two simple ways to generate these operators, from $t$- or $s$-channel tree-level exchange. Fixing the strength of these interactions from the DM relic density constraint, we obtain in particular a magnetic moment that, depending on the interaction considered, lies typically between $10^{-20}$ to $10^{-23}$ ecm or identically vanishes. These non-vanishing values induce, via photon exchange, DM-nucleus scattering cross sections that could be probed by current or near future direct detection experiments.

   hep-phastro-ph.COJHEP(2021)·23 citations
2. 02*

   The axial-vector contributions in two-photon reactions: pion transition form factor and deeply-virtual Compton scattering at NNLO in QCD

   V. M. Braun🇩🇪 · A. N. Manashov🇩🇪 · S. Moch🇩🇪 · J. Schoenleber🇩🇪

   Using the approach based on conformal symmetry we calculate the two-loop coefficient function for the axial-vector contributions to two-photon processes in the $\overline{\mathrm{MS}}$ scheme. This is the last missing element for the complete next-to-next-to-leading order (NNLO) calculation of the the pion transition form factor ${\gamma }^{\ast }\gamma \to \pi$ in perturbative QCD. The corresponding high-statistics measurement is planned by the Belle II collaboration and will allow one to put strong constraints on the pion light-cone distribution amplitude. The calculated NNLO corrections prove to be rather large and have to be taken into account. The same coefficient function determines the contribution of the axial-vector generalized parton distributions to deeply-virtual Compton scattering which is investigated at the JLAB 12 GeV accelerator, by COMPASS at CERN, and in the future will be studied at the Electron Ion Collider EIC.

   hep-phPRD(2021)·37 citations
3. 03*

   Muon g-2 and a type-X two Higgs doublet scenario: some studies in high-scale validity

   Atri Dey🇮🇳 · Jayita Lahiri🇮🇳 · Biswarup Mukhopadhyaya🇮🇳

   We study the high-scale validity of a Type-X two Higgs doublet scenario which provides an explanation of the observed value of muon $(g-2)$. This region admits of a pseudoscalar physical state, which is well below the observed 125-GeV scalar in mass. A second neutral scalar particle can be both above and below 125 GeV in such a scenario. Admissible regions in the parameter space are obtained by using the most recent data on muon $(g-2)$, theoretical constraints such as low-scale perturbativity and vacuum stability, and also all experimental constraints, including the available LHC results. Among other things, both the aforesaid orders of CP-even neutral scalar masses are included in our benchmark studies. Two-loop renormalisation group equations are used to predict the values of various couplings at high scales, and the regions in the space spanned by low-scale parameters, which retain perturbative unitarity as well as vacuum stability upto various scales are identified. We thus conclude that such a scenario, while successfully explaining the observed muon $(g-2)$, can be valid upto energy scales ranging from $10^4$ GeV to the Planck scale, thus opening up directions of thought on its ultraviolet completion.

   hep-phPRD(2022)·26 citations
4. 04*

   Axial Anomaly in Galaxies and the Dark Universe

   Janning Meinert🇩🇪 · Ralf Hofmann🇩🇪

   Motivated by the SU(2)${}_{\mathrm{CMB}}$ modification of the cosmological model $\Lambda$CDM, we consider isolated fuzzy-dark-matter lumps, made of ultralight axion particles whose masses arise due to distinct SU(2) Yang-Mills scales and the Planck mass $M_P$. In contrast to SU(2)${}_{\mathrm{CMB}}$, these Yang-Mills theories are in confining phases (zero temperature) throughout most of the Universe's history and associate with the three lepton flavours of the Standard Model of particle physics. As the Universe expands, axionic fuzzy dark matter comprises a three-component fluid which undergoes certain depercolation transitions when dark energy (a global axion condensate) is converted into dark matter. We extract the lightest axion mass $m_{a,e}=0.675\times 10^{-23}$eV from well motivated model fits to observed rotation curves in low-surface-brightness galaxies (SPARC catalogue). Since the virial mass of an isolated lump solely depends on $M_P$ and the associated Yang-Mills scale the properties of an e-lump predict those of $\mu$- and $\tau$-lumps. As a result, a typical e-lump virial mass $\sim 6.3\times 10^{10}{M}_{\odot }$ suggests that massive compact objects in galactic centers such as Sagittarius A${}^{\ast }$ in the Milky Way are (merged) $\mu$- and $\tau$-lumps. In addition, $\tau$-lumps may constitute globular clusters. SU(2)${}_{\mathrm{CMB}}$ is always thermalised, and its axion condensate never has depercolated. If the axial anomaly indeed would link leptons with dark matter and the CMB with dark energy then this would demystify the dark Universe through a firmly established feature of particle physics.

   hep-phastro-ph.COhep-thUniverse(2021)·15 citations
5. 05*

   Closing the Neutrino "BSM Gap": Physics Potential of Atmospheric Through-Going Muons at DUNE

   Austin Schneider🇺🇸 · Barbara Skrzypek🇺🇸 · Carlos A. Argüelles🇺🇸 · Janet M. Conrad🇺🇸

   Many Beyond-Standard Model physics signatures are enhanced in high-energy neutrino interactions. To explore these signatures, ultra-large Cherenkov detectors such as IceCube exploit event samples with charged current muon neutrino interactions > 1 TeV. Most of these interactions occur below the detector volume, and produce muons that enter the detector. However, the large spacing between detectors leads to inefficiency for measuring muons with energies below or near the critical energy of 400 GeV. In response, IceCube has built a densely instrumented region within the larger detector. This provides large samples of well-reconstructed interactions that are contained within the densely instrumented region, extending up to energies of ~50 GeV. This leaves a gap of relatively unexplored atmospheric-neutrino events with energies between 50 GeV and 1 TeV in the ultra-large detectors. In this paper we point out that interesting Beyond Standard Model signatures may appear in this energy window, and that early running of the DUNE far detectors can give insight into new physics that may appear in this range.

   hep-phhep-exPRD(2021)·11 citations
6. 06*

   Unification of L${}_{\mu }$-L${}_{\tau }$ and the standard model gauge group

   Joe Sato🇯🇵

   In this letter we show a kind of \mt gauge symmetry can be unified into a simple group with the standard model gauge symmetry in the context of coset space unification. We also discuss some implication from one of this kind of unification.

   hep-phJHEP(2022)·3 citations
7. 07*

   Higher-order behaviour of two-point current correlators

   Matthias Jamin🇦🇹

   Estimates of higher-order contributions for perturbative series in QCD, in view of their asymptotic nature, are delicate, though indispensable for a reliable error assessment in phenomenological applications. In this work, the Adler function and the scalar correlator are investigated, and models for Borel transforms of their perturbative series are constructed, which respect general constraints from the operator product expansion and the renormalisation group. As a novel ingredient, the QCD coupling is employed in the so-called $C$-scheme, which has certain advantages. For the Adler function, previous results obtained directly in the $\overline{\mathrm{MS}}$ scheme are supported. Corresponding results for the scalar correlation function are new. It turns out that the substantially larger perturbative corrections for the scalar correlator in $\overline{\mathrm{MS}}$ are dominantly due to this scheme choice, and can be largely reduced through more appropriate renormalisation schemes, which are easy to realise in the $C$-scheme.

   hep-phEur.Phys.J.ST(2021)·12 citations
8. 08*

   Drell-Yan $p_{\perp }$ spectra from fixed-target to LHC energies based on Parton Branching TMDs matched with NLO

   Aleksandra Lelek🇧🇪

   The theoretical description of Drell-Yan (DY) transverse momentum spectra over wide kinematic regions in energy, mass and transverse momentum requires not only fixed-order perturbative QCD calculations but also soft-gluon QCD resummations to all orders of perturbation theory. The latter are traditionally accomplished either by Parton Showers (PS) with Monte Carlo event generators or by (different versions of) analytical procedures. In this work we focus on issues involved in the matching of the fixed-order calculation and resummation, especially in the moderate to low mass and $p_{\perp }$ region. In particular we address the DY region accessible at fixed target experiments. We present a Parton Branching (PB) formulation in which transverse momentum dependent (TMD) evolution is matched with MCatNLO calculations of NLO matrix elements. Using this formulation, we show a good theoretical description of DY data from experiments in very different kinematic ranges: NuSea, R209, Phenix, LHC $8\text{TeV}$ and $13\text{TeV}$.

   hep-ph0 citations
9. 09*

   Physics from Photons at the LHC

   L. A. Harland-Lang🇬🇧

   LHC collisions can act as a source of photons in the initial state. This mechanism plays an important role in the production of particles with electroweak couplings, and a precise account of photon-initiated (PI) production at the LHC is a key ingredient in the LHC precision physics programme. I will discuss the possibility of modelling PI processes directly via the structure function approach. This can provide percent level precision in the production cross sections, and is therefore well positioned to account for LHC precision requirements. This formalism in addition allows one to make use of another useful feature of photons, namely that they are colour-singlet and can often be emitted elastically (or quasi-elastically) from the proton. I will discuss recent work on applications of the structure function approach to precision calculations of PI production in the inclusive mode, and to 'exclusive' processes with rapidity gaps, which can provide a unique probe of the Standard Model and physics beyond it.

   hep-phSciPost Phys.Proc.(2022)·0 citations
10. 10*

    Gluon pseudo-distributions at short distances

    I. Balitsky🇺🇸 · W. Morris🇺🇸 · A. Radyushkin🇺🇸

    We present the results that are necessary in the ongoing lattice calculations of the gluon parton distribution functions (PDFs) within the pseudo-PDF approach. We identify the two-gluon correlator functions that contain the invariant amplitude determining the gluon PDF in the light-cone $z^2\to 0$ limit, and perform one-loop calculations in the coordinate representation in an explicitly gauge-invariant form. Ultraviolet (UV) terms, which contain $\ln (-z^2)$-dependence cancel in the reduced Ioffe-time distribution (ITD), and we obtain the matching relation between the reduced ITD and the light-cone ITD. Using a kernel form, we get a direct connection between lattice data for the reduced ITD and the normalized gluon PDF.

    hep-phhep-latSciPost Phys.Proc.(2022)·11 citations
11. 11*

    Conformal Portal to Dark Matter

    Kunio Kaneta🇰🇷 · Pyungwon Ko🇰🇷 · Wan-Il Park🇰🇷

    We propose a new portal coupling to dark matter by taking advantage of the nonminimally coupled portal sector to the Ricci scalar. Such a portal sector conformally induces couplings to the trace of the energy-momentum tensor of matters including highly secluded dark matter particles. The portal coupling is so feeble that dark matter is produced by freeze-in processes of scatterings and/or the decay of the mediator. We consider two concrete realizations of the portal: conformally induced Higgs portal and conformally induced mediator portal. The former case is compatible with the Higgs inflation, while the latter case can be tested by dark matter direct detection experiments.

    hep-phastro-ph.COPRD(2021)·13 citations
12. 12*

    Early kinetic decoupling and a pseudo-Nambu-Goldstone dark matter model

    Tomohiro Abe🇯🇵

    We study the early kinetic decoupling effect in a pseudo-Nambu-Goldstone (pNG) dark matter (DM) model. The pNG DM scattering processes with particles in the thermal bath in the early Universe are suppressed by the small momentum transfer. As a result, kinetic equilibrium is not maintained, and the temperature of DM is different from the temperature of the thermal bath at the freeze-out era. This temperature difference affects the thermal relic abundance of DM. We investigate the early kinetic decoupling in the Higgs resonance region, 50 GeV $\lesssim m_{\chi }\lesssim m_h/2$, where $m_{\chi }$ is the mass of the DM, and $m_h/2\simeq$ 62.5 GeV. We find that the DM-Higgs coupling determined to obtain the measured value of the DM energy density is underestimated in the literature. The enhancement in the coupling leads larger value of the Higgs invisible decay rate. It enlarges the capability to discover the DM signals from the decay of the Higgs bosons at collider experiments.

    hep-phPRD(2021)·29 citations
13. 13*

    Mixing and $CP$ violation in $D^0\to K^{-}{\pi }^{+}$ decays

    Tommaso Pajero🇬🇧 · Michael Joseph Morello🇮🇹

    We review the experimental methods to measure mixing and time-dependent $CP$ violation in $D^0$ decays into two hadrons. While these phenomena are usually neglected for $D^0\to K^{-}{\pi }^{+}$ decays, this approximation is not always justified. In particular, it produces a bias on the measurement of the parameter $y_{CP}$, when this is performed by relying on $D^0\to K^{-}{\pi }^{+}$ decays as a normalisation channel, whose size is around 40% of the precision of the current world average. Finally, we estimate the sensitivity to the weak mixing phases achievable by studying $D^0\to K^{-}{\pi }^{+}$ and untagged $D\to K^{-}{\pi }^{+}$ decays, where $D$ stands for either of the $D^0$ and ${\bar{D}}^0$ mesons. Contrary to Cabibbo-suppressed $D^0\to h^{+}{h}^{-}$ decays, these decay channels allow to measure these phases without final-state dependent nuisance contributions from the decay amplitudes, but their sensitivity is lower by a factor of six.

    hep-phhep-exJHEP(2022)·18 citations
14. 14*

    Next-to-leading-order QCD corrections to heavy quark fragmentation into ${}^1{S}_0^{(1,8)}$ quarkonia

    Feng Feng (China University of Mining and Technology)🇨🇳 · Yu Jia (Institute of High Energy Physics, Chinese Academy of Sciences)🇨🇳 · Wen-Long Sang (Southwest University)🇨🇳

    Within NRQCD factorization framework, in this work we compute, at the lowest order in velocity expansion, the next-to-leading-order (NLO) perturbative corrections to the short-distance coefficients associated with heavy quark fragmentation into the ${}^1{S}_0^{(1,8)}$ components of a heavy quarkonium. Starting from the Collins and Soper's operator definition of the quark fragmentation function, we apply the sector decomposition method to facilitate the numerical manipulation. It is found that the NLO QCD corrections have a significant impact.

    hep-phEPJC(2021)·9 citations
15. 15*

    Thermal WIMPs and the Scale of New Physics: Global Fits of Dirac Dark Matter Effective Field Theories

    The GAMBIT Collaboration: Peter Athron🇨🇳 · Neal Avis Kozar🇨🇦 · Csaba Balázs🇦🇺 · Ankit Beniwal🇧🇪 · Sanjay Bloor🇬🇧 · Torsten Bringmann🇳🇴 · Joachim Brod🇺🇸 · Christopher Chang🇦🇺 · Jonathan M. Cornell🇺🇸 · Ben Farmer🇦🇺 · Andrew Fowlie🇨🇳 · Tomás E. Gonzalo🇦🇺 and 14 other authors

    We assess the status of a wide class of WIMP dark matter (DM) models in light of the latest experimental results using the global fitting framework $\text{GAMBIT}$. We perform a global analysis of effective field theory (EFT) operators describing the interactions between a gauge-singlet Dirac fermion and the Standard Model quarks, the gluons and the photon. In this bottom-up approach, we simultaneously vary the coefficients of 14 such operators up to dimension 7, along with the DM mass, the scale of new physics and several nuisance parameters. Our likelihood functions include the latest data from $Planck$, direct and indirect detection experiments, and the LHC. For DM masses below 100 GeV, we find that it is impossible to satisfy all constraints simultaneously while maintaining EFT validity at LHC energies. For new physics scales around 1 TeV, our results are influenced by several small excesses in the LHC data and depend on the prescription that we adopt to ensure EFT validity. Furthermore, we find large regions of viable parameter space where the EFT is valid and the relic density can be reproduced, implying that WIMPs can still account for the DM of the universe while being consistent with the latest data.

    hep-phastro-ph.COEPJC(2021)·52 citations
16. 16*

    Extended reduced-order surrogate models for scalar-tensor gravity in the strong field and applications to binary pulsars and gravitational waves

    Minghao Guo🇨🇳 · Junjie Zhao🇨🇳 · Lijing Shao🇨🇳

    Statistically sound tests of scalar-tensor gravity theories in the strong-field regime usually involves computationally intensive calculations. In this study, we construct a reduced order surrogate model for the scalar-tensor gravity of Damour and Esposito-Farèse (DEF) with spontaneous scalarization phenomena developed for neutron stars (NSs). This model allows us to perform a rapid and comprehensive prediction of NS properties, including mass, radius, moment of inertia, effective scalar coupling, and two extra coupling parameters. We code the model in the pySTGROMX package, as an extension of our previous work, that speeds up the calculations at two and even three orders of magnitude and yet still keeps accuracy of $\sim 1\%$. Using the model, we can calculate all the post-Keplerian parameters in the timing of binary pulsars conveniently, which provides a quick approach for us to place comprehensive constraints on the DEF theory. We perform Markov-chain Monte Carlo simulations with the model to constrain the parameters of the DEF theory with well-timed binary pulsars. Utilizing five NS-white dwarf and three NS-NS binaries, we obtain the most stringent constraints on the DEF theory up to now. Our work provides a public tool for quick evaluation of NSs' derived parameters to test gravity in the strong-field regime.

    ↳ gr-qcastro-ph.HEhep-phPRD(2021)·22 citations
17. 17*

    Boson stars and their radial oscillations

    Ben Kain🇺🇸

    We review the derivation of the pulsations equations for spherically symmetric boson stars and then make a thorough study of the radial oscillation frequencies for the fundamental and first excited modes. We do this for self-interacting boson stars and consider a range of values for the self-coupling constant. We also numerically evolve boson stars and Fourier transform the dynamic solutions. The Fourier transform gives an independent computation of the radial oscillation frequencies and allows us to verify our results obtained from the pulsation equations. We find excellent agreement between the two methods.

    ↳ gr-qcastro-ph.HEhep-phPRD(2021)·23 citations
18. 18*

    Lattice gauge theory computation of the static force

    Nora Brambilla🇩🇪 · Viljami Leino🇩🇪 · Owe Philipsen🇩🇪 · Christian Reisinger🇩🇪 · Antonio Vairo🇩🇪 · Marc Wagner🇩🇪

    We explore a novel approach to compute the force between a static quark and a static antiquark with lattice gauge theory directly. The approach is based on expectation values of Wilson loops or Polyakov loops with chromoelectric field insertions. We discuss theoretical and technical aspects in detail, in particular, how to compensate large discretization errors with a multiplicative renormalization factor and the evaluation using a multilevel algorithm. We also compare numerical results for the static force to corresponding results obtained in the traditional way, i.e., by computing first the static potential and then taking the derivative.

    ↳ hep-lathep-phhep-thPRD(2022)·26 citations
19. 19*

    Towards a theory of bottom-up holographic models for linear Regge trajectories of light mesons

    S.S. Afonin🇷🇺 · T.D. Solomko🇷🇺

    We advance in constructing a bottom-up holographic theory of linear meson Regge trajectories that generalizes and unites into one logical framework various bottom-up holographic approaches proposed in the past and scattered in the literature. The starting point of the theory is a quadratic in fields holographic five-dimensional action in which the Poincaré invariance along the holographic coordinate is violated in the most general way compatible with the linear Regge behavior of the discrete spectrum in four dimensions. It is further demonstrated how different Soft Wall (SW) like holographic models existing in the literature plus some new ones emerge from our general setup. Various interrelations between the emerging models are studied. These models include the known SW models with different sign in the exponential background, the SW models with certain generalized backgrounds, with modified metrics, and No Wall models with 5D mass depending on the holographic coordinate in a simple polynomial way. We argue that this dependence allows to describe the effects caused by the main non-local phenomena of strongly coupled 4D gauge theory, the confinement and chiral symmetry breaking, in terms of a local 5D dual field theory in the AdS space. We provide a detailed comparison of our approach with the Light Front holographic QCD, with the spectroscopic predictions of the dual Veneziano like amplitudes, and with the experimental Regge phenomenology. We apply our general approach to a holographic study of confinement, chiral symmetry breaking, and the pion form factor.

    ↳ hep-thhep-phEPJC(2022)·22 citations
20. 20*

    How can gravitational-wave standard sirens and 21 cm intensity mapping jointly provide a precise late-universe cosmological probe?

    Shang-Jie Jin🇨🇳 · Ling-Feng Wang🇨🇳 · Peng-Ju Wu🇨🇳 · Jing-Fei Zhang🇨🇳 · Xin Zhang🇨🇳

    In the next decades, the gravitational-wave (GW) standard siren observations and the neutral hydrogen 21-cm intensity mapping (IM) surveys, as two promising cosmological probes, will play an important role in precisely measuring cosmological parameters. In this work, we make a forecast for cosmological parameter estimation with the synergy between the GW standard siren observations and the 21-cm IM surveys. We choose the Einstein Telescope (ET) and the Taiji observatory as the representatives of the GW detection projects and choose the Square Kilometre Array (SKA) phase I mid-frequency array as the representative of the 21-cm IM experiments. In the simulation of the 21-cm IM data, we assume perfect foreground removal and calibration. We find that the synergy of the GW standard siren observations and the 21-cm IM survey could break the cosmological parameter degeneracies. The joint ET+Taiji+SKA data give $\sigma (H_0)=0.28\mathrm{km}{\mathrm{s}}^{-1}\mathrm{Mp}{\mathrm{c}}^{-1}$ in the $\Lambda$CDM model, $\sigma (w)=0.028$ in the $w$CDM model, which are better than the results of $Planck$+BAO+SNe, and $\sigma (w_0)=0.077$ and $\sigma (w_a)=0.295$ in the CPL model, which are comparable with the results of $Planck$+BAO+SNe. In the $\Lambda$CDM model, the constraint precision of $H_0$ and ${\Omega }_{\mathrm{m}}$ is less than or rather close to 1%, indicating that the magnificent prospects for precision cosmology with these two promising cosmological probes are worth expecting.

    ↳ astro-ph.COgr-qchep-phPRD(2021)·67 citations
21. 21*

    Reply to "Comment on: Cosmological black holes are not described by the Thakurta metric"

    Gert Hütsi🇪🇪 · Tomi Koivisto🇪🇪 · Martti Raidal🇪🇪 · Ville Vaskonen🇪🇸 · Hardi Veermäe🇪🇪

    In this reply, we address the comment [arXiv:2105.14908] to our recent paper [arXiv:2105.09328], where we argued that the Thakurta metric does not describe cosmological black holes. We clarify that the mass growth of Thakurta black holes is due to an influx of energy (i.e. accretion), which, by definition, is not a feature of geometry. The conclusions of [arXiv:2105.09328] are independent of the interpretation of this energy flux. We show that the average energy density of primordial Thakurta black holes scales as $a^{-2}$ and requires an unrealistic and fine-tuned energy transfer from a smooth dark matter component to the primordial black hole sector.

    ↳ astro-ph.COgr-qchep-phhep-th10 citations
22. 22*

    A very high energy hadron collider on the Moon

    James Beacham🇺🇸 · Frank Zimmermann🇨🇭

    The long-term prospect of building a hadron collider around the circumference of a great circle of the Moon is sketched. A Circular Collider on the Moon (CCM) of $\sim$11000 km in circumference could reach a proton-proton center-of-mass collision energy of 14 PeV -- a thousand times higher than the Large Hadron Collider at CERN -- optimistically assuming a dipole magnetic field of 20 T. Several aspects of such a project are presented, including siting, construction, availability of necessary materials on the Moon, and powering, as well as a discussion of future studies and further information needed to determine the more concrete feasibility of each. Machine parameters and vacuum requirements are explored, and an injection scheme is delineated. Other unknowns are set down. Due to the strong interest from multiple organizations in establishing a permanent Moon presence, a CCM could be the (next-to-) next-to-next-generation discovery machine for high-energy particle physics and a natural successor to next-generation machines, such as the proposed Future Circular Collider at CERN or a Super Proton-Proton Collider in China, and other future machines, such as a Collider in the Sea, in the Gulf of Mexico. A CCM would serve as an important stepping stone towards a Planck-scale collider sited in our Solar System.

    ↳ hep-exhep-phphysics.acc-phNew J.Phys.(2022)·13 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.