Fri·Nov 5, 2021Friday·November 5, 2021

1. 01*

   The Effective Vector Boson Approximation in High-Energy Muon Collisions

   Richard Ruiz🇵🇱 · Antonio Costantini🇧🇪 · Fabio Maltoni🇧🇪 · Olivier Mattelaer🇧🇪

   Due to the inclination for forward gauge radiation, lepton colliders beyond a few TeV are effectively electroweak (EW) boson colliders, suggesting the treatment of EW bosons as constituents of high-energy leptons. In the context of a muon collider, we revisit the validity of $W$ and $Z$ parton distribution functions (PDFs) at leading order in $2\to n$ process. We systematically investigate universal and quasi-universal power-law and logarithmic corrections that arise when deriving (polarized) weak boson PDFs in the collinear limit. We go on to survey a multitude of $2\to n$ processes at $\sqrt{s}=2-30$ TeV via polarized and unpolarized EW boson fusion/scattering. To conduct this study, we report a public implementation of the Effective $W/Z$ and Weizsäcker-Williams Approximations, which we collectively call the Effective Vector Boson Approximation, into the Monte Carlo event generator \texttt{MadGraph5\_aMC@NLO}. This implementation lays the groundwork for developing matrix-element matching prescriptions involving EW parton showers and renormalized EW PDFs. To further with this agenda, we give recommendations on using $W/Z$ PDFs.

   hep-phhep-exJHEP(2022)·105 citations
2. 02*

   Does the $J^{PC}=1^{+-}$ counterpart of the $X(3872)$ exist?

   Pablo G. Ortega🇪🇸 · David R. Entem🇪🇸 · Francisco Fernandez🇪🇸

   We explore the possible existence of the $J^{PC}=1^{+-}$ counterpart of the $X(3872)$ state in a coupled-channels calculation within a constituent quark model, with the aim of confirming the existence of the so-called $\tilde{X}(3872)$ state observed by the COMPASS Collaboration. Two states are found in the energy region of the $\tilde{X}(3872)$ signal, both with almost equal mixture of $c\bar{c}$ $2^1{P}_1$ state and $D^{\ast }{\bar{D}}^{(\ast )}$ channels: One that can be identified as the dressed $c\bar{c}$ $2^1{P}_1$ and a bound state below the $D{\bar{D}}^{\ast }$ threshold. We provide predictions of strong and radiative decays that could help to clarify the existence of such structures.

   hep-phPLB(2022)·10 citations
3. 03*

   Neutrino Interactions with Matter and the MiniBooNE anomaly

   Luis Alvarez-Ruso🇪🇸 · Eduardo Saul-Sala🇪🇸

   The excess of electron-like events measured by MiniBooNE challenges our understanding of neutrinos and their interactions. We review the status of this open problem and ongoing efforts to resolve it. After introducing the experiment and its results, we consider the main experimental backgrounds and the related physics of neutrino interactions with matter such as quasielastic-like scattering and weak pion production on nucleons and nuclei. Special attention is paid to single photon emission in neutral current interactions and, in particular, its coherent channel. The difficulties to reconcile the MiniBooNE anomaly with global oscillation analysis is then highlighted. We finally outline some of the proposed solutions of the puzzle involving unconventional neutrino-interaction mechanisms.

   hep-phhep-exnucl-thEur.Phys.J.ST(2021)·27 citations
4. 04*

   (New) Physics at a multi-TeV $\mu$ Collider

   Antonio Costantini🇧🇪

   We present the results of the physics reach of a multi-TeV muon collider for popular models of physics beyond the Standard Model. We include also details about a model predicting the scalar dark matter in the spectrum. Finally we present some preliminary results about the Effective Vector Approximation and its implementation in the Monte Carlo generator {\sc MadGraph5\_aMC@NLO}.

   hep-phPoS(2022)·3 citations
5. 05*

   Status of negative coupling modifiers for extended Higgs sectors

   Carlos Henrique de Lima🇨🇦 · Daniel Stolarski🇨🇦 · Yongcheng Wu🇺🇸

   In this work, we study the status of negative coupling modifiers in extended Higgs sectors, focusing on the ratio of coupling modifiers that probes custodial symmetry violation ${\lambda }_{WZ}={\kappa }_W/{\kappa }_Z$. Higgs sectors with multiplets larger than doublets are the only weakly coupled models that give tree-level modifications to ${\lambda }_{WZ}$, and we explore all such models allowed by the constraint from the $\rho$ parameter and perturbative unitarity. This class of models has a custodial symmetry violating potential, while the vacuum configuration preserves the symmetry. We apply precision measurements from ATLAS and CMS and show that each data set can exclude a vast set of models with ${\lambda }_{WZ}<0$ at greater than 95\% confidence level. We give evidence that ${\lambda }_{WZ}<0$ is excluded in all weakly coupled models. [Erratum for this work on page 19 changing our claims of complete exclusion of negative ${\lambda }_{WZ}$ to a softer version where only the minimal models are excluded.]

   hep-phPRD(2022)·9 citations
6. 06*

   Leptonic Meson Decays into Invisible ALP

   Jorge Alda Gallo🇪🇸 · Alfredo Walter Mario Guerrera🇮🇹 · Siannah Peñaranda🇪🇸 · Stefano Rigolin🇮🇹

   The theoretical calculation of pseudo-scalar leptonic decay widths into an invisible ALP, $M\to \ell {\nu }_{\ell }a$, is reviewed. Assuming generic flavour-conserving ALP couplings to SM fermions and a generic ALP mass, $m_a$, the latest experimental results for pseudo-scalar leptonic decays are used to provide updated bounds on the ALP-fermion Lagrangian sector. Constrains on the ALP-quark couplings obtained from these channels are not yet competitive with the ones derived from FCNC processes, like $M\to Pa$ decays. These leptonic decays can, however, provide the most stringent model-independent upper bounds on ALP-leptons couplings for $m_a$ in the (sub)-GeV range.

   hep-phNPB(2022)·25 citations
7. 07*

   Systematic study of the $SU(3{)}_c\otimes SU(3{)}_L\otimes U(1{)}_X$ local gauge symmetry

   Richard H. Benavides🇨🇴 · Yithsbey Giraldo🇨🇴 · Luis Muñoz🇨🇴 · William A. Ponce🇨🇴 · Eduardo Rojas🇨🇴

   We review in a systematic way how anomaly free $SU(3{)}_c\otimes SU(3{)}_L\otimes U(1{)}_x$ models without exotic electric charges can be constructed, using as basis closed sets of fermions which includes each one the particles and antiparticles of all the electrically charged fields. Our analysis reproduce not only the known models in the literature, but also shows the existence of several more independent models for one and three families not considered so far. A phenomenological analysis of the new models is done, where the lowest limits at a 95\% CL on the gauge boson masses are presented.

   hep-phJ.Phys.G(2022)·5 citations
8. 08*

   Enhanced Radiation ? from (Super) Conductor by Dark Matter Axion

   Aiichi Iwazaki🇯🇵

   In our previous paper we have shown that enhanced radiations arise from (super) conductor by dark matter axion under strong magnetic field. We have recalculated the radiation by carefully treating boundary conditions between vacuum and the conductor. We show that the radiation is never enhanced. We interpret it such that electromagnetic field induced by axion collides the conductor and it is reflected by the conductor. The reflecting wave is the radiation from the conductor. It is reasonable that the amplitude of the reflection wave is identical to that of the incoming wave, i.e. radiation induced by axion.

   hep-ph1 citation
9. 09*

   Anomaly detection from mass unspecific jet tagging

   J. A. Aguilar-Saavedra🇪🇸

   We introduce a novel anomaly search method based on (i) jet tagging to select interesting events, which are less likely to be produced by background processes; (ii) comparison of the untagged and tagged samples to single out features (such as bumps produced by the decay of new particles) in the latter. We demonstrate the usefulness of this method by applying it to a final state with two massive boosted jets: for the new physics benchmarks considered, the signal significance increases an order of magnitude, up to a factor of 40. We compare to other anomaly detection methods in the literature and discuss possible generalisations.

   hep-phhep-exEPJC(2022)·26 citations
10. 10*

    The h(125) decays to c cbar, b bbar, b sbar, photon photon and gluon gluon in the light of the MSSM with quark flavor violation

    Keisho Hidaka (1)🇯🇵 · Helmut Eberl (2)🇦🇹 · Elena Ginina (2) ((1) Tokyo Gakugei U., (2) HEPHY, Vienna)🇦🇹

    We study the Higgs boson decays $h^0\to c\bar{c},b\bar{b},b\bar{s},\gamma \gamma ,gg$ in the Minimal Supersymmetric Standard Model (MSSM) with general quark flavor violation (QFV), identifying the $h^0$ as the Higgs boson with a mass of 125 GeV. We compute the widths of the $h^0$ decays to $c\bar{c},b\bar{b},b\bar{s}(s\bar{b})$ at full one-loop level. For the $h^0$ decays to photon photon and gluon gluon we compute the widths at NLO QCD level. We perform a systematic MSSM parameter scan respecting all the relevant constraints, i.e. theoretical constraints from vacuum stability conditions and experimental constraints, such as those from K- and B-meson data and electroweak precision data, as well as recent limits on Supersymmetric (SUSY) particle masses and the 125 GeV Higgs boson data from LHC experiments. From the parameter scan, we find that the deviations of these MSSM widths from the Standard Model (SM) values can be quite sizable. All of these large deviations in the $h^0$ decays are due to large scharm-stop mixing, large scharm/stop involved trilinear couplings $T_{U23},T_{U32},T_{U33}$, large sstrange-sbottom mixing, and large sstrange/sbottom involved trilinear couplings $T_{D23},T_{D32},T_{D33}$. International Linear Collider (ILC) can observe such large deviations from the SM at high signal significance. In case the deviation pattern shown here is really observed at ILC, then it would strongly suggest the discovery of QFV SUSY (the MSSM with QFV).

    hep-phPoS(2022)·1 citation
11. 11*

    Electric current on surface of a metal/superconductor in axion/hidden-photon background

    Yasuhiro Kishimoto🇯🇵 · Kazunori Nakayama🇯🇵

    We derive the electric current on surface of a normal metal or superconductor induced by the light bosonic dark matter, such as axion or hidden photon, by appropriately taking account of the boundary condition of the electric and magnetic field at the surface. We discuss detection possibility of such an electric current.

    hep-phPLB(2022)·3 citations
12. 12*

    (Reply to)${}^{\text{2}}$ "Comment on 'Flavor invariants and renormalization-group equations in the leptonic sector with massive Majorana neutrinos' "

    Jianlong Lu🇸🇬

    We respectfully reply to Wang et al.'s reply to our comment to their [JHEP $\text{09}$ (2021) 053]. Some more subtleties and details are discussed for hopefully better clarification and understanding, especially about the conditions in Hilbert's finiteness theorem. We also disprove Wang et al.'s incorrect assertion in their reply [arXiv:2110.13865 [hep-ph]] that there is an isomorphism between $\mathrm{U}(n,\mathbb{C})$ and $\mathrm{GL}(n,\mathbb{C})$. We give two proofs for our argument. One proof is in the context of Lie group for arbitrary positive integer $n$, and the other proof is in the context of abstract group for $n=3$ which can also be generalized to $n\ge 3$. In order to better illustrate the intrinsic differences between a compact Lie group and its complexification, we choose $\mathrm{SU}(n,\mathbb{C})$ and $\mathrm{SL}(n,\mathbb{C})$ as a pair of examples and give two proofs for the generally non-isomorphic relation between them. One proof is in the context of Lie group for integers $n\ge 2$, and the other proof is in the context of abstract group for $n=3$ which can again be generalized to $n\ge 3$.

    hep-ph12 citations
13. 13*

    Boer-Mulders function of the pion and pretzelosity distribution of the proton in the polarized pion-proton Drell-Yan process at COMPASS

    Xiaonan Liu🇨🇳 · Bo-Qiang Ma🇨🇳

    We present a phenomenological analysis of the $q_{\mathrm{T}}$-weighted transverse spin dependent azimuthal asymmetry recently measured by the COMPASS Collaboration in polarized pion-proton Drell-Yan process. In the kinematical regimes explored by experiments, we consider the leading-twist contributions from the Boer-Mulders distribution functions $h_1^{\perp }(x,k_{\mathrm{T}}^2)$ of both the pion and the proton, the transversity distribution $h_1(x,k_{\mathrm{T}}^2)$ and the pretzelosity distribution $h_{1\mathrm{T}}^{\perp }(x,k_{\mathrm{T}}^2)$ of the proton, with the unpolarized transverse-momentum-dependent distribution function $f_1(x,k_{\mathrm{T}}^2)$ of the proton being also involved in the calculation. By comparing the data reported by the COMPASS Collaboration with theoretical calculated results, we find that the COMPASS measurements represent the first experimental evidence of the Boer-Mulders effect in polarized Drell-Yan process. We also test the universality between proton and pion Boer-Mulders functions.

    hep-phEPJC(2021)·3 citations
14. 14*

    Comparison of lattice QCD results for inclusive semi-leptonic decays of $B$ mesons with the OPE

    Paolo Gambino🇮🇹 · Shoji Hashimoto🇯🇵 · Sandro Mächler

    A recently proposed approach to compute the inclusive semi-leptonic decay rate on the lattice allows for the calculation of various quantities (differential distributions and moments) in different subchannels. We systematically compare the lattice QCD results for an unphysically light bottom quark with OPE-based predictions, including leading order perturbative and $\mathcal{O}\left(1/m^3\right)$ power corrections, and explore possible strategies to decrease the systematic uncertainty.

    hep-phhep-latPoS(2022)·5 citations
15. 15*

    Slope of the topological charge, proton spin and $0^{-+}$ pseudoscalar di-gluonia spectra

    Stephan Narison (LUPM-CNRS-Montpellier-FR and iHEPMAD-Antananarivo-MG)🇫🇷

    We discuss the topics mentioned in the title by scrutinizing and improving the $0^{-+}$ di-gluonia sum rules within the standard SVZ-expansion at N2LO without instantons. First, we reconsider the estimate of the slope of the topological charge ${\chi }^{\prime }(0)=24.3(3.4)$ MeV which imply $0.144(5)[\mathrm{data}:0.145(13)]$ for the first moment of the polarized proton structure function (proton spin) and $G_A^{(0)}=0.337(50)[\mathrm{data}=0.330(39)]$ for the singlet form factor of the axial current. Second, we work with high degree moments and parametrize the spectral function beyond the minimal duality ansatz: "One resonance plus QCD continuum" to get the $0^{-+}$ di-gluonia spectra. Then, we obtain three groups of gluonia: The familiar light ${\eta }_1$ [singlet gluon component of the ${\eta }^{\prime }(958)$] with $[M_{{\eta }_1},f_{{\eta }_1}]=[825,905(72)]$; The two new medium gluonia with $M_{P_{1a}}=1338(112)$ MeV and $[M_{P_{1b}}=1462(117)$ MeV or their mean $[M_{P_1},f_{P_1}]=[1397(81),594(144)]$ MeV which support the gluonium nature of the candidate $\eta (1405)$ and may bring a small gluon piece to the $\eta (1295)$; Their 1st radial excitations: $M_{P_{1a}^{\prime }}=1508(226)$ MeV and $M_{P_{1b}^{\prime }}=1553(139)$ MeV with their mean: $[M_{P_1^{\prime }},f_{P_1^{\prime }}]=[1541(118),205(282)]$ MeV which may be identified (up to some eventual mixings with $\bar{q}q$ states) with the $\eta (1475,1700)$ states; The heavy gluonium with : $[M_{P_2},f_{P_2}]=[2751(140),500(43)]$ MeV comparable with the lattice results. One can remark the (natural) one to one correspondence between the pseudoscalar gluonia and their chiral scalar analogue from Ref.1: $\sigma (1)\to {\eta }_1;G_1(1.55)\to P_1;[{\sigma }^{\prime }(1.1),G^{\prime }(1.56)]\to P_{1a,1b}^{\prime };G_2(3)\to P_2$ which is mainly due to the importance of QCD PT in the sum rule analysis that are almost equal in these two channels. Results for the spectra are in Table 2.

    hep-phhep-exhep-latNPA(2022)·8 citations
16. 16*

    A data-based parametrization of parton distribution functions

    Stefano Carrazza🇮🇹 · Juan M. Cruz-Martinez🇮🇹 · Roy Stegeman🇮🇹

    Since the first determination of a structure function many decades ago, all methodologies used to determine structure functions or parton distribution functions (PDFs) have employed a common prefactor as part of the parametrization. The NNPDF collaboration pioneered the use of neural networks to overcome the inherent bias of constraining the space of solution with a fixed functional form while still keeping the same common prefactor as a preprocessing. Over the years various, increasingly sophisticated, techniques have been introduced to counter the effect of the prefactor on the PDF determination. In this paper we present a methodology to remove the prefactor entirely, thereby significantly simplifying the methodology, without a loss of efficiency and finding good agreement with previous results.

    hep-phEPJC(2022)·22 citations
17. 17*

    Leptophilic Dark Matter at Linear Colliders

    P. S. Bhupal Dev🇺🇸

    We discuss model-independent collider constraints on the effective couplings of leptophilic dark matter (LDM), considering its production at a future electron-positron linear collider, with both polarized and unpolarized beam options, in the mono-photon and mono-$Z$ channels. We show that the future collider constraints are largely complementary to the direct and indirect detection limits on LDM, and can potentially provide the best-ever LDM sensitivity in the low-mass regime (below $\sim$ 10 GeV).

    hep-phThe Sixteenth Marcel Grossmann Meeting, p…·1 citation
18. 18*

    Non-standard interactions from the future neutrino solar sector

    P. Martínez-Miravé🇪🇸 · S. Molina Sedgwick🇪🇸 · M.Tórtola🇪🇸

    The next-generation neutrino experiment JUNO will determine the solar oscillation parameters - ${\sin }^2{\theta }_{12}$ and $\Delta m_{21}^2$ - with great accuracy, in addition to measuring ${\sin }^2{\theta }_{13}$, $\Delta m_{31}^2$, and the mass ordering. In parallel, the continued study of solar neutrinos at Hyper-Kamiokande will provide complementary measurements in the solar sector. In this paper, we address the expected sensitivity to non-universal and flavour-changing non-standard interactions (NSI) with $d$-type quarks from the combination of these two future neutrino experiments. We also show the robustness of their measurements of the solar parameters ${\sin }^2{\theta }_{12}$ and $\Delta m_{21}^2$ in the presence of NSI. We study the impact of the exact experimental configuration of the Hyper-Kamiokande detector, and conclude it is of little relevance in this scenario. Finally, we find that the LMA-D solution is expected to be present if no additional input from non-oscillation experiments is considered.

    hep-phhep-exPRD(2022)·16 citations
19. 19*

    Screening models and neutrino oscillations

    H. Yazdani Ahmadabadi🇮🇷 · H. Mohseni Sadjadi🇮🇷

    In screening models with scalar-matter conformal coupling, we study the flavor transition of neutrinos. We employ an analytical method for studying the oscillation phase in a spherically symmetric spacetime filled by a scalar field. Since the ambient matter density determines the scalar field's behavior, an indirect environmental effect contributes to the flavor conversion inside matter. We evaluate the survival probabilities and show that the existence of the scalar field affects the oscillations of neutrinos. We discuss the results in the framework of screening mechanisms and the end, confront our results with observational data.

    hep-phgr-qchep-thPhys.Dark Univ.(2022)·7 citations
20. 20*

    Galactic rotation curves versus ultralight dark matter: A systematic comparison with SPARC data

    Nitsan Bar🇮🇱 · Kfir Blum🇮🇱 · Chen Sun🇮🇱

    We look for and place observational constraints on the imprint of ultralight dark matter (ULDM) soliton cores in rotation-dominated galaxies. Extending previous analyses, we find a conservative constraint which disfavors the soliton-host halo relation found in some numerical simulations over a broad range in the ULDM particle mass $m$. Combining the observational constraints with theoretical arguments for the efficiency of soliton formation via gravitational dynamical relaxation, and assuming that the soliton-halo relation is correct, our results disfavor ULDM from comprising 100\% of the total cosmological dark matter in the range $10^{-24}\mathrm{eV}\lesssim m\lesssim 10^{-20}\mathrm{eV}$. The constraints probe the ULDM fraction down to $f\lesssim 0.3$ of the total dark matter.

    hep-phastro-ph.COastro-ph.GAPRD(2022)·90 citations
21. 21*

    Single top production in association with a $WZ$ pair at the LHC in the SMEFT

    Hesham El Faham🇧🇪 · Fabio Maltoni🇧🇪 · Ken Mimasu🇬🇧 · Marco Zaro🇮🇹

    We study single top quark production in association with a $WZ$ pair at the LHC in the context of the Standard Model (SM) and the Standard Model Effective Field Theory (SMEFT). A significant advantage of $tWZ$ compared to other EW top production processes is its sensitivity to unitarity-violating behaviour induced in its $2\to 2$ sub-amplitudes through modified EW interactions. At NLO in QCD, $tWZ$ interferes with $t\bar{t}Z$ and $t\bar{t}$ and a method to meaningfully separate it from these overlapping processes needs to be employed. In order to define $tWZ$ production for total rates and differential distributions, we consider the approaches proposed in the literature for similar cases and find that diagram-removal procedures provide reliable results both for the SM and the SMEFT in a suitably defined phase-space region. We provide robust results for total and differential cross sections for $tWZ$ at 13 TeV, including the six relevant dimension-6 operators (${\mathcal{O}}_{tW}$,${\mathcal{O}}_{tZ}$,${\mathcal{O}}_{tG}$,${\mathcal{O}}_{\varphi Q}^{(-)}$,${\mathcal{O}}_{\varphi Q}^{(3)}$,${\mathcal{O}}_{\varphi t}$), also matching short-distance events to parton shower.

    hep-phJHEP(2022)·34 citations
22. 22*

    Leptoflavorgenesis: baryon asymmetry of the Universe from lepton flavor violation

    Kyohei Mukaida🇯🇵 · Kai Schmitz🇨🇭 · Masaki Yamada🇯🇵

    Charged-lepton flavor violation (CLFV) is a smoking-gun signature of physics beyond the Standard Model. The discovery of CLFV in upcoming experiments would indicate that CLFV processes must have been efficient in the early Universe at relatively low temperatures. In this letter, we point out that such efficient CLFV interactions open up new ways of creating the baryon asymmetry of the Universe. First, we quote the two-loop corrections from charged-lepton Yukawa interactions to the chemical transport in the Standard Model plasma, which imply that nonzero lepton flavor asymmetries summing up to $B-L=0$ are enough to generate the baryon asymmetry. Then, we describe two scenarios of what we call {\it leptoflavorgenesis}, where efficient CLFV processes are responsible for the generation of primordial lepton flavor asymmetries that are subsequently converted to a baryon asymmetry by weak sphaleron processes. Here, the conversion factor from lepton flavor asymmetry to baryon asymmetry is suppressed by charged-lepton Yukawa couplings squared, which provides a natural explanation for the smallness of the observed baryon-to-photon ratio.

    hep-phastro-ph.COPRL(2022)·26 citations
23. 23*

    NuFIT: Three-Flavour Global Analyses of Neutrino Oscillation Experiments

    M.C. Gonzalez-Garcia🇪🇸 · Michele Maltoni🇪🇸 · Thomas Schwetz🇩🇪

    In this contribution, we summarise the determination of neutrino masses and mixing arising from global analysis of data from atmospheric, solar, reactor, and accelerator neutrino experiments performed in the framework of three-neutrino mixing and obtained in the context of the NuFIT collaboration. Apart from presenting the latest status as of autumn 2021, we discuss the evolution of global-fit results over the last 10 years, and mention various pending issues (and their resolution) that occurred during that period in the global analyses.

    hep-phhep-exUniverse(2021)·156 citations
24. 24*

    Cosmological implications of EW vacuum instability: constraints on the Higgs-curvature coupling from inflation

    Andreas Mantziris🇬🇧

    The current experimentally measured parameters of the Standard Model (SM) suggest that our Universe lies in a metastable electroweak vacuum, where the Higgs field is prone to vacuum decay to a lower state with catastrophic consequences. Our measurements dictate that such an event has not taken place yet, despite the many different mechanisms that could have triggered it in our past light-cone. The focus of our work has been to calculate the probability of the false vacuum to decay during the period of inflation and use it to constrain the last unknown renormalisable SM parameter $\xi$, which couples the Higgs field with space-time curvature. More specifically, we derived lower $\xi$-bounds from vacuum stability in three inflationary models: quadratic and quartic chaotic inflation, and Starobinsky-like power-law inflation. We also took the time-dependence of the Hubble rate into account both in the geometry of our past light-cone and in the Higgs effective potential, which is approximated with three-loop renormalisation group improvement supplemented with one-loop curvature corrections.

    ↳ astro-ph.COgr-qchep-phhep-thPoS(2022)·3 citations
25. 25*

    On the cosmological implications of the electroweak vacuum instability: constraining the non-minimal coupling with inflation

    Andreas Mantziris🇬🇧

    Our current measurements of the Standard Model parameters imply that the Higgs field resides in a metastable electroweak vacuum, where the vacuum can decay to a lower ground state, with cataclysmic repercussions for our Universe. According to our observations, no such event has happened in the observable universe, in spite of the various energetic processes that could have triggered it. This work serves as an overview of a method that uses the metastability of the false vacuum during cosmological inflation to provide constraints on the Higgs curvature coupling $\xi$. Considering also the effects of the time-dependent Hubble rate on the effective Higgs potential and on our past light-cone space-time geometry, results in state-of-the-art lower $\xi$-bounds from quadratic and quartic chaotic inflation, and Starobinsky-like power-law inflation.

    ↳ astro-ph.COgr-qchep-phhep-thJ.Phys.Conf.Ser.(2021)·3 citations
26. 26*

    Espectroscopia Mesónica Moderna: o Papel Fundamental da Unitariedade

    Eef van Beveren🇵🇹 · George Rupp🇵🇹

    The importance of implementing unitarity constraints in meson spectroscopy is very briefly outlined for Portuguese students of engineering sciences and therefore non-experts in the field. After explaining the profound differences between meson spectroscopy and atomic spectroscopy, attention is paid to the shortcomings of standard Breit-Wigner parametrisations in the case of broad and/or overlapping resonances. Finally, the manifestly unitary Resonance-Spectrum-Expansion model, which lies at the heart of a recent invited review paper by the present authors, is graphically presented, together with a simple yet typical application to the long-controversial $K_0^{\star }(700)$ resonance.

    ↳ physics.pop-phhep-phT\'{e}cnica, Vol. 504, pp. 24-27 (2021)·0 citations
27. 27*

    Origin and evolution of the multiply-quantised vortex instability

    Sam Patrick🇨🇦 · August Geelmuyden🇬🇧 · Sebastian Erne🇬🇧 · Carlo F. Barenghi🇬🇧 · Silke Weinfurtner🇬🇧

    We show that the dynamical instability of quantum vortices with more than a single quantum of angular momentum results from a superradiant bound state inside the vortex core. Our conclusion is supported by an analytic WKB calculation and numerical simulations of both linearised and fully non-linear equations of motion for a doubly-quantised vortex at the centre of a circular bucket trap. In the late stage of the instability, we reveal a striking novel behaviour of the system in the non-linear regime. Contrary to expectation, in the absence of dissipation the system never enters the regime of two well-separated phase defects described by Hamiltonian vortex dynamics. Instead, the separation between the two defects undergoes modulations which never exceed a few healing lengths, in which compressible kinetic energy and incompressible kinetic energy are exchanged. This suggests that, under the right conditions, pairs of vortices may be able to form meta-stable bound states.

    ↳ cond-mat.quant-gashep-phhep-thphysics.flu-dynPRResearch(2022)·18 citations
28. 28*

    Unusual Emission Variations Near the Eclipse of A Black Widow PSR J1720$-$0533

    S.Q.Wang🇨🇳 · J.B.Wang🇨🇳 · N.Wang🇨🇳 · J.M.Yao🇨🇳 · G.Hobbs🇦🇺 · S.Dai🇦🇺 · F.F.Kou🇨🇳 · C.C.Miao🇨🇳 · D.Li🇨🇳 · Y. Feng🇨🇳 · S.J. Dang🇨🇳 · D.H. Wang🇨🇳 and 6 other authors

    We report on an {unusually} bright observation of PSR J1720$-$0533 using the Five-hundred-meter Aperture Spherical radio Telescope (FAST). The pulsar is in a black widow system that {was discovered by the Commensal Radio Astronomy FAST Survey (CRAFTS). By coincidence, a bright scintillation maximum was simultaneous with the eclipse in our observation which allowed for precise measurements of flux density variations, as well as dispersion measure (DM) and polarization.} We found that there are quasi-periodic pulse emission variations with a modulation period of $\sim$ {22\,s} during the ingress of the eclipse, which could be caused by plasma lensing. {No such periodic modulation was found during the egress of the eclipse. } {The linear polarization of the pulsar disappears before the eclipse, even before there is a visually obvious change in DM. We also found that the pulse scattering maybe play an important role in the eclipse of PSR J1720$-$0533.}

    ↳ astro-ph.HEhep-phApJL(2021)·17 citations
29. 29*

    Misinterpreting Modified Gravity as Dark Energy: a Quantitative Study

    Yuewei Wen🇺🇸 · Eva Nesbit🇺🇸 · Dragan Huterer🇺🇸 · Scott Watson🇺🇸

    Standard cosmological data analyses typically constrain simple phenomenological dark-energy parameters, for example the present-day value of the equation of state parameter, $w_0$, and its variation with scale factor, $w_a$. However, results from such an analysis cannot easily indicate the presence of modified gravity. Even if general relativity does not hold, experimental data could still be fit sufficiently well by a phenomenological $w_0{w}_a$CDM, unmodified-gravity model. Hence, it would be very useful to know if there are generic signatures of modified gravity in standard analyses. Here we present, for the first time to our knowledge, a quantitative mapping showing how modified gravity models look when (mis)interpreted within the standard unmodified-gravity analysis. Scanning through a broad space of modified-gravity (Horndeski) models, and assuming a near-future survey consisting of CMB, BAO, and SNIa observations, we report values of the best-fit set of cosmological parameters including $(w_0,w_a)$ that would be inferred if modified gravity were at work. We find that modified gravity models that can masquerade as standard gravity lead to very specific biases in standard-parameter spaces. We also comment on implications for measurements of the amplitude of mass fluctuations described by the parameter $S_8$.

    ↳ astro-ph.COgr-qchep-phJCAP(2022)·8 citations
30. 30*

    Constraining the nucleon size with relativistic nuclear collisions

    Giuliano Giacalone🇩🇪 · Björn Schenke🇺🇸 · Chun Shen🇺🇸

    The notion of the "size" of nucleons and their constituents plays a pivotal role in the current paradigm of the formation and the fluctuations of the quark-gluon plasma produced in high-energy nuclear collision experiments. We report on state-of-the-art hydrodynamic results showing that the correlation between anisotropic flow, $v_n^2$, and the mean transverse momentum of hadrons, $[p_t]$, possesses a unique sensitivity to the nucleon size in off-central heavy-ion collisions. We argue that existing experimental measurements of this observable support a picture where the relevant length scale characterizing the colliding nucleons is of order 0.5 fm or smaller, and we discuss the broad implications of this finding for future global Bayesian analyses aimed at extracting initial-state and medium properties from nucleus-nucleus collision data, including $v_n^2$-$[p_t]$ correlations. Determinations of the nucleon size in heavy-ion collisions will provide a solid independent constraint on the initial state of small system collisions, and will establish a deep connection between collective flow data in nucleus-nucleus experiments and data on deep inelastic scattering on protons and nuclei.

    ↳ nucl-thhep-exhep-phnucl-exPRL(2022)·43 citations
31. 31*

    Charmonium-like resonances in coupled $D\bar{D}$-$D_s{\bar{D}}_s$ scattering

    S. Prelovsek🇸🇮 · S. Collins🇩🇪 · D. Mohler🇩🇪 · M. Padmanath🇩🇪 · S. Piemonte

    Charmonium-like resonances and bound states with isospin zero and $J^{PC}=0^{++},1^{--},2^{++},3^{--}$ are extracted on the lattice. Coupled $D\bar{D}$ and $D_s{\bar{D}}_s$ scattering suggests three charmonium-like states with $J^{PC}=0^{++}$ in addition to ${\chi }_{c0}(1P)$: a so far unobserved $D\bar{D}$ bound state just below threshold, a conventional resonance likely related to ${\chi }_{c0}(3860)/{\chi }_{c0}(2P)$ and a narrow resonance just below the $D_s{\bar{D}}_s$ threshold with a large coupling to $D_s{\bar{D}}_s$ likely related to $X(3915)/{\chi }_{c0}(3930)$. One-channel $D\bar{D}$ scattering renders resonances and bound states with $J^{PC}=1^{--},2^{++},3^{--}$ related to the observed conventional charmonia. Lattice QCD ensembles from the CLS consortium with $m_{\pi }\simeq 280$ MeV are utilized.

    ↳ hep-lathep-phPoS(2022)·3 citations
32. 32*

    Muonphilic Dark Matter explanation of gamma-ray galactic center excess: a comprehensive analysis

    Murat Abdughani🇨🇳 · Yi-Zhong Fan🇨🇳 · Chih-Ting Lu🇰🇷 · Tian-Peng Tang🇨🇳 · Yue-Lin Sming Tsai🇨🇳

    The Galactic center gamma-ray excess (GCE) is a long-standing unsolved problem. One of candidate solutions, the dark matter (DM) annihilation, has been recently tested with other astrophysical observations, such as AMS-02 electron-positron spectra, Fermi Dwarf spheroidal galaxies gamma-ray data, and so on. By assuming that the DM particles annihilate purely into a normal charged fermion pair, Di Mauro and Winkle (2021) claimed that only a muon-pair is compatible with the null detection of all the corresponding astrophysical measurements and can explain GCE simultaneously. On the other hand, a muonphilic DM model may also lead to a signal in the recent Fermilab muon $g-2$ measurement or be constrained by the latest PandaX-4T limit. In this work, we comprehensively study interactions between DM and muon, including various combinations of DM and mediator spins. In agreement with GCE (not only $2\mu$ but also $4\mu$ final states), we test these interactions against all the thermal DM constraints. Our results show that only the parameter space near the resonance region of mediator can explain GCE and relic density simultaneously, and larger parameter spaces are still allowed if other poorly-known systematic uncertainties are included. Regardless of the DM spin, only the interactions with the spin-0 mediator can explain the recent muon $g-2$ excess on top of GCE, relic density, and other DM and mediator constraints.

    ↳ astro-ph.HEhep-phJHEP(2022)·19 citations
33. 33*

    Full-color three-loop three-point form factors in N=4 SYM

    Guanda Lin🇨🇳 · Gang Yang🇨🇳 · Siyuan Zhang🇨🇳

    We present the detailed computation of full-color three-loop three-point form factors of both the stress-tensor supermultiplet and a length-three BPS operator in N=4 SYM. The integrands are constructed based on the color-kinematics (CK) duality and generalized unitarity method. An interesting observation is that the CK-dual integrands contain a large number of free parameters. We discuss the origin of these free parameters in detail and check that they cancel in the simplified integrands. We further perform the numerical evaluation of the integrals at a special kinematics point using public packages FIESTA and pySecDec based on the sector-decomposition approach. We find that the numerical computation can be significantly simplified by expressing the integrals in terms of uniformly transcendental basis, although the final three-loop computations still require large computational resources. Having the full-color numerical results, we verify that the non-planar infrared divergences reproduce the non-dipole structures, which firstly appear at three loops. As for the finite remainder functions, we check that the numerical planar remainder for the stress-tensor supermultiplet is consistent with the known result of the bootstrap computation. We also obtain for the first time the numerical results of the three-loop non-planar remainder for the stress-tensor supermultiplet as well as the three-loop remainder for the length-three operator.

    ↳ hep-thhep-phJHEP(2022)·36 citations
34. 34*

    LHC experiments for long-lived particles of the dark sector

    Vasiliki A. Mitsou🇪🇸

    Dark matter scenarios are being tested at the LHC in the general-purpose experiments through promptly decaying states. In parallel, new dedicated detectors have been proposed for the LHC to probe dark matter portal theories predicting long-lived particles that decay away from the interaction point: MoEDAL-MAPP, MoEDAL-MALL, FASER, SND@LHC, CODEX-b, MATHUSLA, AL3X, ANUBIS, FACET, milliQan, FORMOSA. In addition, the SHiP beam-dump experiment is planned to operate with the SPS beam to extend the discovery reach for such particles. The detector design and expected physics sensitivity of these experiments is presented with emphasis on scenarios explaining the nature of dark matter.

    ↳ hep-exhep-phphysics.ins-det15 citations
35. 35*

    Geometric Soft Theorems

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

    We derive a universal soft theorem for every scattering amplitude with at least one massless particle in an arbitrary theory of scalars. Our results follow from the geometry of field space and are valid for any choice of mass spectrum, potential terms, and higher-derivative interactions. For a vanishing potential, the soft limit of every amplitude is equal to the field-space covariant derivative of an amplitude with one fewer particle. Furthermore, the Adler zero and the dilaton soft theorem are special cases of our results. We also discuss more exotic scenarios in which the soft limit is non-trivial but still universal. Last but not least, we derive new theorems for multiple-soft limits which directly probe the field-space curvature, as well as on-shell recursion relations applicable to two-derivative scalar field theories exhibiting no symmetries whatsoever.

    ↳ hep-thhep-phJHEP(2022)·85 citations
36. 36*

    Cosmic Filament Spin from Dark Matter Vortices

    Stephon Alexander🇺🇸 · Christian Capanelli🇺🇸 · Elisa G. M. Ferreira🇩🇪 · Evan McDonough🇨🇦

    The recent observational evidence for cosmic filament spin on megaparsec scales (Wang et al, Nature Astronomy 5, 839-845 (2021)) demands an explanation in the physics of dark matter. Conventional collisionless cold particle dark matter is conjectured to generate cosmic filament spin through tidal torquing, but this explanation requires extrapolating from the quasi-linear regime to the non-linear regime. Meanwhile no alternative explanation exists in the context of ultra-light (e.g., axion) dark matter, and indeed these models would naively predict zero spin for cosmic filaments. In this Letter we study cosmic filament spin in theories of ultra-light dark matter, such as ultra-light axions, and bosonic and fermionic condensates, such as superfluids and superconductors. These models are distinguished from conventional particle dark matter models by the possibility of dark matter vortices. We take a model agnostic approach, and demonstrate that a collection of dark vortices can explain the data reported in Wang et al. Modeling a collection of vortices with a simple two-parameter analytic model, corresponding to an averaging of the velocity field, we find an excellent fit to the data. We perform a Markov Chain Monte Carlo analysis and find constraints on the number of vortices, the dark matter mass, and the radius of the inner core region where the vortices are distributed, in order for ultra-light dark matter to explain spinning cosmic filaments.

    ↳ astro-ph.COgr-qchep-phhep-thPLB(2022)·21 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.