Wed·Jul 8, 2020Wednesday·July 8, 2020

1. 01*

   ScannerS: Parameter Scans in Extended Scalar Sectors

   Margarete Mühlleitner🇩🇪 · Marco O. P. Sampaio🇵🇹 · Rui Santos🇵🇹 · Jonas Wittbrodt🇸🇪

   We present the public code ScannerS-2 that performs parameter scans and checks parameter points in theories beyond the Standard Model (BSM) with extended scalar sectors. ScannerS incorporates theoretical and experimental constraints from many different sources in order to judge whether a parameter point is allowed or excluded at approximately 95% CL. The BSM models implemented in ScannerS include many popular BSM models such as singlet extensions, different versions of the Two-Higgs-Doublet Model, or the different phases of the Next-to Two-Higgs-Doublet Model. The ScannerS framework allows straightforward extensions by additional constraints and BSM models.

   hep-phEPJC(2022)·127 citations
2. 02*

   Renormalisation scale setting for D-mixing

   Alexander Lenz🇬🇧 · Maria Laura Piscopo🇬🇧 · Christos Vlahos🇬🇧

   A naive application of the heavy quark expansion (HQE) yields theory estimates for the decay rate of neutral $D$ mesons that are four orders of magnitude below the experimental determination. It is well known that this huge suppression results from severe GIM cancellations. We find that this mismatch can be solved by individually choosing the renormalisation scale of the different internal quark contributions. For $b$ and $c$ hadron lifetimes, as well as for the decay rate difference of neutral $B$ mesons the effect of our scale setting procedure lies within the previously quoted theory uncertainties, while we get enlarged theory uncertainties for the semi-leptonic CP asymmetries in the $B$ system.

   hep-phhep-exhep-latPRD(2020)·28 citations
3. 03*

   Toward $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}$ annihilation inspired by higher $\rho$ mesonic states around 2.2 GeV

   Li-Ming Wang🇨🇳 · Jun-Zhang Wang🇨🇳 · Xiang Liu🇨🇳

   Very recently, the {\it BABAR} Collaboration indicated that there exist an explicit enhancement structure near 2.2 GeV when focusing on the $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}$ process again, which inspires our interest in studying the production of higher $\rho$ mesonic states. Since the branching ratio of ${\pi }^{+}{\pi }^{-}$ channel of $D-$wave $\rho$ states are much smaller than $S-$wave states, we choose $\rho (1900)$ and $\rho (2150)$ as the intermediate states in $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}$, where $\rho (1900)$ and $\rho (2150)$ are treated as $\rho (3S)$ and $\rho (4S)$ states, respectively. Our result indicates that the $BABAR$'s data of $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}$ around 2 GeV can be depicted well, which shows that this enhancement structure near 2.2 GeV existing in $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}$ can be due to the contribution from two $\rho$ mesons, $\rho (1900)$ and $\rho (2150)$. Additionally, this conclusion can be enforced by the consistence of the extracted values of ${\Gamma }_{e^{+}{e}^{-}}\mathcal{B}({\pi }^{+}{\pi }^{-})$ of $\rho (1900)$ and $\rho (2150)$ in the whole fitting processes and the corresponding theoretical calculations. The present study of $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}$ data may provide valuable information to establish the $\rho$ meson family.

   hep-phhep-exPRD(2020)·13 citations
4. 04*

   Decay properties of beauty and charm mesons within Isgur-Wise function formalism

   C. W. Xiao🇨🇳 · S. Rahmani🇨🇳 · H. Hassanabadi🇮🇷

   We investigate the decay properties of some beauty and charm mesons with a phenomenological potential model. First, we consider the nonrelativistic Hamiltonian of the mesonic system with Coulomb plus exponential terms and study the wave function and the energy of the system using the variational approach. Thereby, we compute the masses, the decay constants, the leptonic branching fractions of heavy-light mesons and the mixing mass parameter $\Delta m_{B_q}$. We study the radiative leptonic decay widths of $D_s\to \gamma \ell \bar{\nu }$, $D^{-}\to \gamma \ell \bar{\nu }$ and the semileptonic decay widths of ${\bar{B}}_{(s)}\to D_{(s)}\ell \bar{\nu }$, ${\bar{B}}_{(s)}\to D_{(s)}^{\ast }\ell \bar{\nu }$. Using Isgur-Wise functions, we calculate the branching ratios of $B\to D^{(\ast )}\pi$ and two-body nonleptonic decay of $D\to K\pi$. Our results are consistent with other theoretical models and the experimental results.

   hep-phEur.Phys.J.Plus(2021)·6 citations
5. 05*

   Direct detection of vector dark matter through electromagnetic multipoles

   Junji Hisano🇯🇵 · Alejandro Ibarra🇩🇪 · Ryo Nagai🇮🇹

   Dark matter particles, even if they are electrically neutral, could interact with the Standard Model particles via their electromagnetic multipole moments. In this paper, we focus on the electromagnetic properties of the complex vector dark matter candidate, which can be described by means of seven form factors. We calculate the differential scattering cross-section with nuclei due to the interactions of the dark matter and nuclear multipole moments, and we derive upper limits on the former from the non-observation of dark matter signals in direct detection experiments. We also present a model where the dark matter particle is a gauge boson of a dark $SU(2)$ symmetry, and which contains heavy new fermions, charged both under the dark $SU(2)$ symmetry and under the electromagnetic $U(1)$ symmetry. The new fermions induce at the one loop level electromagnetic multipole moments, which could lead to detectable signals in direct detection experiments.

   hep-phJCAP(2020)·26 citations
6. 06*

   New physics at nuSTORM

   Kaustav Chakraborty🇮🇳 · Srubabati Goswami🇮🇳 · Kenneth Long🇬🇧

   In this work we investigate the usefulness of nuSTORM as a probe of two new-physics scenarios which are sterile neutrinos and non-unitarity of the neutrino mixing matrix. For the sterile neutrino we show the importance of the neutral current events when combined with the charged current events to constrain the effective mixing angle, ${\theta }_{\mu \mu }$, and the sterile mixing angles ${\theta }_{14}$ and ${\theta }_{24}$. We also study the role nuSTORM will play in the study of neutrino oscillation physics if the three generation neutrino mixing matrix is non-unitary. In this context we elucidate the role of nuSTORM, considering both charged current and neutral current events, in constraining the various non-unitarity parameters such as ${\alpha }_{11}$, $|{\alpha }_{21}|$ and ${\alpha }_{22}$.

   hep-phhep-exPRD(2021)·4 citations
7. 07*

   Process dependence of the gluon Sivers function in $p^{\uparrow }p\to J/\psi +X$ within a TMD approach in NRQCD

   Umberto D'Alesio🇮🇹 · Luca Maxia🇮🇹 · Francesco Murgia🇮🇹 · Cristian Pisano🇮🇹 · Sangem Rajesh🇮🇹

   We consider the transverse single-spin asymmetry (SSA) for $J/\psi$ production in $p^{\uparrow }p\to J/\psi +X$ within a TMD approach in non-relativistic QCD. Extending a previous study [1], we employ here the color-gauge invariant generalized parton model (CGI-GPM), in which spin and intrinsic transverse momentum effects are taken into account, together with leading-order initial- and final-state interactions (ISIs and FSIs). We find that, even when the heavy-quark pair is produced in a color-octet state, ISIs and FSIs lead to a nonvanishing SSA, allowing, in principle, to test the process dependence of the gluon Sivers function (GSF). We show that of the two independent contributions, due to the so-called $f$- and $d$-type GSFs, appearing in the CGI-GPM, the $d$-type one turns out to be dynamically suppressed. Therefore, as already found adopting the Color-Singlet Model approach for the $J/\psi$ formation [2], only the $f$-type GSF could play a role in phenomenology. A comparison with the corresponding results obtained in the generalized parton model, without the inclusion of ISIs and FSIs, is also carried out.

   hep-phPRD(2020)·38 citations
8. 08*

   Density of States of a Coupled-Channel System

   Pok Man Lo🇵🇱

   We demonstrate how an effective density of states can be derived from the S-matrix describing a coupled-channel system. Besides the locations of poles, the phase of the determinant of the S-matrix encodes essential details in characterizing the dynamics of resonant and non-resonant interactions. The density of states is computed for the two channel scattering problem ($\pi \pi ,K\bar{K}$, S-wave), and the influences from the various dynamical structures: poles, roots, branch cuts, and Riemann sheets, are examined.

   hep-phnucl-thPRD(2020)·16 citations
9. 09*

   Flavor anomalies from asymptotically safe gravity

   Kamila Kowalska🇵🇱 · Enrico Maria Sessolo🇵🇱 · Yasuhiro Yamamoto🇵🇱

   We use the framework of asymptotically safe quantum gravity to derive predictions for scalar leptoquark solutions to the $b\to s$ and $b\to c$ flavor anomalies. The presence of an interactive UV fixed point in the system of gauge and Yukawa couplings imposes a set of boundary conditions at the Planck scale, which allows one to determine low-energy values of the leptoquark Yukawa matrix elements. As a consequence, the allowed leptoquark mass range can be significantly narrowed down. We find that a consistent gravity-driven solution to the $b\to s$ anomalies predicts a leptoquark with the mass of 4-7 TeV, entirely within the reach of a future hadron-hadron collider with $\sqrt{s}=100$ TeV. Conversely, in the case of the $b\to c$ anomalies the asymptotically safe gravity framework predicts a leptoquark mass at the edge of the current LHC bounds. Complementary signatures appear in flavor observables, namely the (semi)leptonic decays of B and D mesons and kaons.

   hep-phEPJC(2021)·40 citations
10. 10*

    Signatures of Ultralight Dark Matter in Neutrino Oscillation Experiments

    Abhish Dev🇺🇸 · Pedro A.N. Machado🇺🇸 · Pablo Martínez-Miravé🇪🇸

    We study how neutrino oscillations could probe the existence of ultralight bosonic dark matter. Three distinct signatures on neutrino oscillations are identified, depending on the mass of the dark matter and the specific experimental setup. These are time modulation signals, oscillation probability distortions due to fast modulations, and fast varying matter effects. We provide all the necessary information to perform a bottom-up, model-independent experimental analysis to probe such scenarios. Using the future DUNE experiment as an example, we estimate its sensitivity to ultralight scalar dark matter. Our results could be easily used by any other oscillation experiment.

    hep-phJHEP(2021)·61 citations
11. 11*

    ILC Study Questions for Snowmass 2021

    Keisuke Fujii🇯🇵 · Christophe Grojean🇩🇪 · Michael E. Peskin🇺🇸 · Tim Barklow🇺🇸 · Yuanning Gao🇨🇳 · Shinya Kanemura🇯🇵 · Jenny List🇩🇪 · Mihoko Nojiri🇯🇵 · Maxim Perelstein🇺🇸 · Roman Poeschl🇫🇷 · Juergen Reuter🇩🇪 · Frank Simon🇩🇪 and 23 other authors

    To aid contributions to the Snowmass 2021 US Community Study on physics at the International Linear Collider and other proposed $e^{+}{e}^{-}$ colliders, we present a list of study questions that could be the basis of useful Snowmass projects. We accompany this with links to references and resources on $e^{+}{e}^{-}$ physics, and a description of a new software framework that we are preparing for $e^{+}{e}^{-}$ studies at Snowmass.

    hep-phhep-ex19 citations
12. 12*

    Undulating Dark Matter

    Joe Davighi🇬🇧 · Matthew McCullough🇨🇭 · Joseph Tooby-Smith🇬🇧

    We suggest that an interplay between microscopic and macroscopic physics can give rise to dark matter (DM) whose interactions with the visible sector fundamentally undulate in time, independent of celestial dynamics. A concrete example is provided by fermionic DM with an electric dipole moment (EDM) sourced by an oscillating axion-like field, resulting in undulations in the scattering rate. The discovery potential of light DM searches can be enhanced by additionally searching for undulating scattering rates, especially in detection regions where background rates are large and difficult to estimate, such as for DM masses in the vicinity of 1 MeV where DM-electron scattering dominantly populates the single electron bin. An undulating signal could also reveal precious dark sector information after discovery. In this regard we emphasise that, if the recent XENON1T excess of events is due to light DM scattering exothermically off electrons, future analyses of the time-dependence of events could offer clues as to the microscopic origins of the putative signal.

    hep-phhep-exJHEP(2020)·12 citations
13. 13*

    Precise dark matter relic abundance in decoupled sectors

    Torsten Bringmann🇳🇴 · Paul Frederik Depta🇩🇪 · Marco Hufnagel🇩🇪 · Kai Schmidt-Hoberg🇩🇪

    Dark matter (DM) as a thermal relic of the primordial plasma is increasingly pressured by direct and indirect searches, while the same production mechanism in a decoupled sector is much less constrained. We extend the standard treatment of the freeze-out process to such scenarios and perform precision calculations of the annihilation cross-section required to match the observed DM abundance. We demonstrate that the difference to the canonical value of this 'thermal cross-section' is generally sizeable, and can reach orders of magnitude. Our results directly impact the interpretation of DM searches in hidden sector scenarios.

    hep-phastro-ph.COPLB(2021)·50 citations
14. 14*

    GeV-scale neutrinos: interactions with mesons and DUNE sensitivity

    Pilar Coloma🇪🇸 · Enrique Fernandez-Martinez🇪🇸 · Manuel Gonzalez-Lopez🇪🇸 · Josu Hernandez-Garcia🇭🇺 · Zarko Pavlovic🇺🇸

    The simplest extension of the SM to account for the observed neutrino masses and mixings is the addition of at least two singlet fermions (or right-handed neutrinos). If their masses lie at or below the GeV scale, such new fermions would be produced in meson decays. Similarly, provided they are sufficiently heavy, their decay channels may involve mesons in the final state. Although the couplings between mesons and heavy neutrinos have been computed previously, significant discrepancies can be found in the literature. The aim of this paper is to clarify such discrepancies and provide consistent expressions for all relevant effective operators involving mesons with masses up to 2 GeV. Moreover, the effective Lagrangians obtained for both the Dirac and Majorana scenarios are made publicly available as FeynRules models so that fully differential event distributions can be easily simulated. As an application of our setup, we numerically compute the expected sensitivity of the DUNE near detector to these heavy neutral leptons.

    hep-phhep-exEPJC(2021)·121 citations
15. 15*

    Phenomenology of Magnetic Black Holes with Electroweak-Symmetric Coronas

    Yang Bai🇺🇸 · Joshua Berger🇺🇸 · Mrunal Korwar🇺🇸 · Nicholas Orlofsky🇺🇸

    Magnetically charged black holes (MBHs) are interesting solutions of the Standard Model and general relativity. They may possess a "hairy" electroweak-symmetric corona outside the event horizon, which speeds up their Hawking radiation and leads them to become nearly extremal on short timescales. Their masses could range from the Planck scale up to the Earth mass. We study various methods to search for primordially produced MBHs and estimate the upper limits on their abundance. We revisit the Parker bound on magnetic monopoles and show that it can be extended by several orders of magnitude using the large-scale coherent magnetic fields in Andromeda. This sets a mass-independent constraint that MBHs have an abundance less than $6\times 10^{-3}$ times that of dark matter. MBHs can also be captured in astrophysical systems like the Sun, the Earth, or neutron stars. There, they can become non-extremal either from merging with an oppositely charged MBH or absorbing nucleons. The resulting Hawking radiation can be detected as neutrinos, photons, or heat. High-energy neutrino searches in particular can set a stronger bound than the Parker bound for some MBH masses, down to an abundance $10^{-7}$ of dark matter.

    hep-phastro-ph.HEhep-thJHEP(2020)·57 citations
16. 16*

    Stringent constraints on the light boson model with supermassive black hole spin measurements

    Lei Zu🇨🇳 · Lei Feng🇨🇳 · Qiang Yuan🇨🇳 · Yi-Zhong Fan🇨🇳

    Massive bosons, such as light scalars and vector bosons, can lead to instabilities of rotating black holes by the superradiance effect, which extracts energy and angular momentum from rapidly-rotating black holes effectively. This process results in spinning-down of black holes and the formation of boson clouds around them. In this work, we used the masses and spins of supermassive black holes measured from the ultraviolet/optical or X-ray observations to constrain the model parameters of the light bosons. We find that the mass range of light bosons from $10^{-22}$ eV to $10^{-17}$ eV can be largely excluded by a set of supermassive black holes (including also the extremely massive ones OJ 287, Ton 618 and SDSS J140821.67+025733.2), particularly for the vector boson scenario, which eliminates a good fraction of the so-called fuzzy dark matter parameter regions. For the scalar bosons with self-interaction, most part of the mass range from $\sim 3\times 10^{-19}$ eV to $10^{-17}$ eV with a decay constant $f_a>10^{15}$ GeV can be excluded, which convincingly eliminate the QCD axions at these masses.

    ↳ astro-ph.HEhep-phEur.Phys.J.Plus(2020)·11 citations
17. 17*

    Ab-initio calculation of the proton and the neutron's scalar couplings for new physics searches

    Sz. Borsanyi🇩🇪 · Z. Fodor🇩🇪 · C. Hoelbling🇩🇪 · L. Lellouch🇫🇷 · K.K. Szabo🇩🇪 · C. Torrero🇫🇷 · L. Varnhorst🇩🇪

    Many low-energy, particle-physics experiments seek to reveal new fundamental physics by searching for very rare scattering events on atomic nuclei. The interpretation of their results requires quantifying the non-linear effects of the strong interaction on the spin-independent couplings of this new physics to protons and neutrons. Here we present a fully-controlled, ab-initio calculation of these couplings to the quarks within those constituents of nuclei. We use lattice quantum chromodynamics computations for the four lightest species of quarks and heavy-quark expansions for the remaining two. We determine each of the six quark contributions with an accuracy better than 15%. Our results are especially important for guiding and interpreting experimental searches for our universe's dark matter.

    ↳ hep-lathep-ph46 citations
18. 18*

    Irreducible background of gravitational waves from a cosmic defect network: update and comparison of numerical techniques

    Daniel G. Figueroa🇪🇸 · Mark Hindmarsh🇫🇮 · Joanes Lizarraga🇪🇸 · Jon Urrestilla🇪🇸

    Cosmological phase transitions in the early Universe may produce relics in the form of a network of cosmic defects. Independently of the order of a phase transition, topology of the defects, and their global or gauge nature, the defects are expected to emit gravitational waves (GWs) as the network energy-momentum tensor adapts itself to maintaining {scaling}. We show that the evolution of any defect network (and for that matter any scaling source) emits a GW background with spectrum ${\Omega }_{\mathrm{GW}}\propto f^3$ for $f\ll f_0$, ${\Omega }_{\mathrm{GW}}\propto 1/f^2$ for $f_0\lesssim f\lesssim f_{\mathrm{eq}}$, and ${\Omega }_{\mathrm{GW}}\propto const$ (i.e.~exactly scale-invariant) for $f\gg f_{\mathrm{eq}}$, where $f_0$ and $f_{\mathrm{eq}}$ denote respectively the frequencies corresponding to the present and matter-radiation equality horizons. This background represents an irreducible emission of GWs from any scaling network of cosmic defects, with its amplitude characterized only by the symmetry breaking scale and the nature of the defects. Using classical lattice simulations we calculate the GW signal emitted by defects created after the breaking of a global symmetry $O(N)\to O(N-1)$. We obtain the GW spectrum for $N$ between 2 and 20 with two different techniques: integrating over unequal time correlators of the energy momentum tensor, updating our previous work on smaller lattices, and for the first time, comparing the result with the real time evolution of the tensor perturbations sourced by the same defects. Our results validate the equivalence of the two techniques. Using CMB upper bounds on the defects' energy scale, we discuss the difficulty of detecting this GW background in the case of global defects.

    ↳ astro-ph.COgr-qchep-phhep-thPRD(2020)·59 citations
19. 19*

    Spectral functions and dynamic critical behavior of relativistic $Z_2$ theories

    Dominik Schweitzer🇩🇪 · Sören Schlichting🇩🇪 · Lorenz von Smekal🇩🇪

    We investigate the dynamic critical behaviour of a relativistic scalar field theory with $Z_2$ symmetry by calculating spectral functions of the order parameter at zero and non-vanishing momenta from first-principles classical-statistical lattice simulations in real-time. We find that at temperatures above the critical point $(T>T_c)$, the spectral functions are well described by relativistic quasi-particle peaks. Close to the transition temperature $(T\sim T_c)$, we observe strong infrared contributions building up. In the ordered phase at low temperatures $(T<T_c)$, in addition to the quasi-particle peak, we observe a soft mode with a dispersion relation indicative of collective excitations. Investigating the spectral functions close to $T_c$, we demonstrate that the behavior in the vicinity of the critical point is controlled by dynamic scaling functions and the dynamic critical exponent $z$, which we determine from our simulations. By considering the equations of motion for a closed system and a system coupled to a heat bath, we extract the dynamic critical behavior for two different dynamic universality classes (Models A & C) in two and three spatial dimensions.

    ↳ hep-latcond-mat.stat-mechhep-phnucl-thNPB(2020)·35 citations
20. 20*

    Early recombination as a solution to the $H_0$ tension

    Toyokazu Sekiguchi🇯🇵 · Tomo Takahashi🇯🇵

    We show that the $H_0$ tension can be resolved by making recombination earlier, keeping the fit to cosmic microwave background (CMB) data almost intact. We provide a suite of general necessary conditions to give a good fit to CMB data while realizing a high value of $H_0$ suggested by local measurements. As a concrete example for a successful scenario with early recombination, we demonstrate that a model with time-varying $m_e$ can indeed satisfy all the conditions. We further show that such a model can also be well fitted to low-$z$ distance measurements of baryon acoustic oscillation (BAO) and type-Ia supernovae (SNeIa) with a simple extension of the model. Time-varying $m_e$ in the framework of ${\Omega }_k\Lambda$CDM is found to be a sufficient and excellent example as a solution to the $H_0$ tension, yielding $H_0=72.3_{-2.8}^{+2.7}$km/sec/Mpc from the combination of CMB, BAO and SNeIa data even without incorporating any direct local $H_0$ measurements. Apart from the $H_0$ tension, this model is also favored from the viewpoint of the CMB lensing anomaly.

    ↳ astro-ph.COgr-qchep-phPRD(2021)·156 citations
21. 21*

    Gravitational dark matter production in Palatini preheating

    Alexandros Karam🇪🇪 · Martti Raidal🇪🇪 · Eemeli Tomberg🇪🇪

    We study preheating in plateau inflation in the Palatini formulation of general relativity, in a special case that resembles Higgs inflation. It was previously shown that the oscillating inflaton field returns to the plateau repeatedly in this model, and this leads to tachyonic production of inflaton particles. We show that a minimally coupled spectator scalar field can be produced even more efficiently by a similar mechanism. The mechanism is purely gravitational, and the scalar field mass can be of order $10^{13}$ GeV, larger than the Hubble scale by many orders of magnitude, making this a candidate for superheavy dark matter.

    ↳ astro-ph.COgr-qchep-phhep-thJCAP(2021)·47 citations
22. 22*

    Comparison of Different Methods for Calculation of the Normalized Mott Cross Section

    P.B. Kats🇧🇾 · K.V. Halenka🇧🇾 · O.O. Voskresenskaya🇷🇺

    An intercomparison of some earlier methods for calculating the normalized Mott cross section and also a method proposed by the authors of the present work is carried out. It is demonstrated that applying the given method, along with the method of Lijian et al., is preferable for relevant calculations.

    ↳ nucl-thhep-ph0 citations
23. 23*

    Efficient emulators for scattering using eigenvector continuation

    R.J. Furnstahl🇺🇸 · A.J. Garcia🇺🇸 · P.J. Millican🇺🇸 · Xilin Zhang🇺🇸

    Eigenvector continuation EC has been shown to accurately and efficiently reproduce ground states for targeted sets of Hamiltonian parameters. It uses as variational basis vectors the corresponding ground-state eigensolutions from selected other sets of parameters. Here we extend the EC approach to scattering using the Kohn variational principle. We first test it using a model for S-wave nucleon-nucleon scattering and then demonstrate that it also works to give accurate predictions for non-local potentials, charged-particle scattering, complex optical potentials, and higher partial waves. These proofs-of-principle validate EC as an accurate emulator for applying Bayesian inference to parameter estimation constrained by scattering observables. The efficiency of such emulators is because the accuracy is achieved with a small number of variational basis elements and the central computations are just linear algebra calculations in the space spanned by this basis.

    ↳ nucl-thcond-mat.mtrl-scihep-lathep-ph+1PLB(2020)·79 citations
24. 24*

    Cross sections for coherent elastic and inelastic neutrino-nucleus scattering

    N. Van Dessel🇧🇪 · V. Pandey🇺🇸 · H. Ray🇺🇸 · N. Jachowicz🇧🇪

    The prospects of extracting new physics signals in coherent elastic neutrino--nucleus scattering (CE$\nu$NS) processes are limited by the precision with which the underlying nuclear structure physics, embedded in the weak nuclear form factor, is known. We present calculations of charge and weak nuclear form factors and CE$\nu$NS cross sections on ${}^{12}$C, ${}^{16}$O, ${}^{40}$Ar, ${}^{56}$Fe and ${}^{208}$Pb nuclei. We obtain the proton and neutron densities, and charge and weak form factors by solving Hartree--Fock (HF) equations with a Skyrme (SkE2) nuclear potential. We validate our approach by comparing ${}^{208}$Pb and ${}^{40}$Ar charge form factor predictions with available elastic electron scattering data. Since CE$\nu$NS experiments at stopped--pion sources are also well suited to measure inelastic charged--current and neutral--current neutrino--nucleus cross sections, we also present calculations for these processes, incorporating a continuum Random Phase Approximation (CRPA) description on top of the HF-SkE2 picture of the nucleus. Providing both coherent as well as inelastic cross sections in a consistent framework, we aim at obtaining a reliable and detailed comparison of the strength of these processes in the energy region below ~100 MeV. Furthermore, we attempt to gauge the level of theoretical uncertainty pertaining to the description of the ${}^{40}$Ar form factor and CE$\nu$NS cross sections by comparing relative differences between recent microscopic nuclear theory and widely--used phenomenological form factor predictions. Future precision measurements of CE$\nu$NS will potentially help in constraining these nuclear structure details that will in turn improve prospects of extracting new physics.

    ↳ nucl-thhep-exhep-phUniverse(2023)·33 citations
25. 25*

    Is GW170817 a Multimessenger Neutron Star-Primordial Black Hole Merger?

    Yu-Dai Tsai🇺🇸 · Antonella Palmese🇺🇸 · Stefano Profumo🇺🇸 · Tesla Jeltema🇺🇸

    We investigate the possibility of the gravitational-wave event GW170817 being a light, solar-mass black hole (BH) - neutron star (NS) merger. We explore two exotic scenarios involving primordial black holes (PBH) that could produce such an event, taking into account available observational information on NGC 4993. First, we entertain the possibility of dynamical NS-PBH binary formation where a solar-mass PBH and a NS form a binary through gravitational interaction. We find that while dynamical NS-PBH formation could account for the GW170817 event, the rate is highly dependent on unknown density contrast factors and could potentially be affected by galaxy mergers. We also find that PBH-PBH binaries would likely have a larger merger rate, assuming the density contrast boost factor of an order similar to the NS-PBH case. These exotic merger formations could provide new channels to account for the volumetric rate of compact-object mergers reported by LIGO/Virgo. Secondly, we consider the case where one of the NS's in a binary NS system is imploded by a microscopic PBH. We find that the predicted rate for NS implosion into a BH is very small, at least for the specific environment of NGC 4993. We point out that similar existing (e.g. GW190425 and GW190814) and future observations will shed additional light on these scenarios.

    ↳ astro-ph.HEastro-ph.COastro-ph.GAgr-qc+1JCAP(2021)·30 citations
26. 26*

    Sensitivities of KM3NeT on decaying dark matter

    Kenny C. Y. Ng🇳🇱 · Ariane Dekker🇳🇱 · Shin'ichiro Ando🇳🇱 · Bjarne Bouwer🇳🇱 · Maurice Geijsen🇳🇱 · Claudia Glazener🇳🇱 · June Groothuizen🇳🇱 · Jildou Hollander🇳🇱 · M. J. F. M. Janssen🇳🇱 · Lukas Kemme🇳🇱 · Wessel Krah🇳🇱 · Sancho Luijten Perona🇳🇱 · Mnême Stapel🇳🇱 · Martijn van Hamersveld🇳🇱

    The discovery of high-energy astrophysical neutrinos by IceCube has opened a new window to the Universe. However, the origin of these neutrinos is still a mystery, and some of them could be a result of dark matter interactions such as decay. Next generation gigaton water-Cherenkov neutrino telescope, KM3NeT, is expected to offer significantly improved energy resolution in the cascade channel, and advantageous viewing condition to the Galactic Center; both important for searches of dark matter decay signals. We study the sensitivity of KM3NeT on dark matter decays by performing a mock likelihood analysis for both cascade and track type events, taking into account both angular and energy information. We find that, combining both channels, KM3NeT is expected to produce world leading limits on dark matter decay lifetime in the PeV mass range, and could test some of the dark matter hints in the current IceCube data.

    ↳ astro-ph.HEastro-ph.COhep-ph13 citations
27. 27*

    Soft de Sitter Effective Theory

    Timothy Cohen🇺🇸 · Daniel Green🇺🇸

    Calculating the quantum evolution of a de Sitter universe on superhorizon scales is notoriously difficult. To address this challenge, we introduce the Soft de Sitter Effective Theory (SdSET). This framework holds for superhorizon modes whose comoving momentum is far below the UV scale, which is set by the inverse comoving horizon. The SdSET is formulated using the same approach that yields the Heavy Quark Effective Theory. The degrees of freedom that capture the long wavelength dynamics are identified with the growing and decaying solutions to the equations of motion. The operator expansion is organized using a power counting scheme, and loops can be regulated while respecting the low energy symmetries. For massive quantum fields in a fixed de Sitter background, power counting implies that all interactions beyond the horizon are irrelevant. Alternatively, if the fields are very light, the leading interactions are at most marginal, and resumming the associated logarithms using (dynamical) renormalization group techniques yields the evolution equation for canonical stochastic inflation. The SdSET is also applicable to models where gravity is dynamical, including inflation. In this case, diffeomorphism invariance ensures that all interactions are irrelevant, trivially implying the all-orders conservation of adiabatic density fluctuations and gravitational waves. We briefly touch on the application to slow-roll eternal inflation by identifying novel relevant operators. This work serves to demystify many aspects of perturbation theory outside the horizon, and has a variety of applications to problems of cosmological interest.

    ↳ hep-thastro-ph.COgr-qchep-phJHEP(2020)·106 citations
28. 28*

    Axion and neutrino bounds improved with new calibrations of the tip of the red-giant branch using geometric distance determinations

    Francesco Capozzi (MPP Munich)🇩🇪 · Georg Raffelt (MPP Munich)🇩🇪

    The brightness of the tip of the red-giant branch (TRGB) allows one to constrain novel energy losses that would lead to a larger core mass at helium ignition and thus to a brighter TRGB than expected by standard stellar models. The required absolute TRGB calibrations strongly improve with reliable geometric distances that have become available for the galaxy NGC 4258 that hosts a water megamaser and to the Large Magellanic Cloud based on 20 detached eclipsing binaries. Moreover, we revise a previous TRGB calibration in the globular cluster $\omega$ Centauri with a recent kinematical distance determination based on Gaia DR2 data. All of these calibrations have similar uncertainties and they agree with each other and with recent dedicated stellar models. Using NGC 4258 as the cleanest extra-galactic case, we thus find an updated constraint on the axion-electron coupling of $g_{ae}<1.6\times 10^{-13}$ and ${\mu }_{\nu }<1.5\times 10^{-12}{\mu }_{\mathrm{B}}$ (95\% CL) on a possible neutrino dipole moment, whereas $\omega$ Centauri as the best galactic target provides instead $g_{ae}<1.3\times 10^{-13}$ and ${\mu }_{\nu }<1.2\times 10^{-12}{\mu }_{\mathrm{B}}$. The reduced observational errors imply that stellar evolution theory and bolometric corrections begin to dominate the overall uncertainties.

    ↳ astro-ph.SRastro-ph.GAhep-phPRD(2020)·257 citations
29. 29*

    Stirred and shaken: dynamical behavior of boson stars and dark matter cores

    Lorenzo Annulli🇵🇹 · Vitor Cardoso🇵🇹 · Rodrigo Vicente🇵🇹

    Bosonic fields can give rise to self-gravitating structures. These are interesting hypothetical new "dark matter stars" and good descriptions of dark matter haloes if the fields are very light. We study the dynamical response of Newtonian boson stars (NBS) when excited by external matter (stars, planets or black holes) in their vicinities. Our setup can describe the interaction between a massive black hole and the surrounding environment, shortly after the massive body has undergone a "kick", due to the collapse of baryonic matter at the galactic center, or dark matter depletion as a reaction to an inspiralling binary. We perform the first self-consistent calculation of dynamical friction acting on moving bodies in these backgrounds. Binaries close to coalescence "stir" the NBS core, and backreaction affects gravitational waveforms at leading $-6PN$ order with respect to the dominant quadrupolar term; the coefficient is too small to allow detection by next-generation interferometers. We also show that the gravitational collapse to a supermassive black hole at the center of a NBS is accompanied by only a small change in the surrounding core. The NBS eventually gets accreted, but for astrophysical parameters this occurs only after several Hubble times.

    ↳ astro-ph.HEgr-qchep-phPLB(2020)·61 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.