Fri·Apr 24, 2020Friday·April 24, 2020

1. 01*

   Self-interacting neutrinos: solution to Hubble tension versus experimental constraints

   Kun-Feng Lyu🇨🇳 · Emmanuel Stamou🇨🇭 · Lian-Tao Wang🇺🇸

   Exotic self-interactions among the Standard-Model neutrinos have been proposed as a potential reason behind the tension in the expansion rate, H0, of the universe inferred from different observations. We constrain this proposal using electroweak precision observables, rare meson decays, and neutrinoless double-\{beta} decay. In contrast to previous works, we emphasize the importance of carrying out this study in a framework with full Standard-Model gauge invariance. We implement this first by working with a relevant set of Standard- Model-Effective-Field-Theory operators and subsequently by considering a UV completion in the inverse See-Saw model. We find that the scenario in which all flavors of neutrinos self-interact universally is strongly constrained, disfavoring a potential solution to the H0 problem in this case. The scenario with self-interactions only among tau neutrinos is the least constrained and can potentially be consistent with a solution to the H0 problem.

   hep-phastro-ph.COPRD(2021)·75 citations
2. 02*

   Spin-$1/2$ invisible particles in heavy meson decays

   Geng Li🇨🇳 · Tianhong Wang🇨🇳 · Yue Jiang🇨🇳 · Jing-Bo Zhang🇨🇳 · Guo-Li Wang🇨🇳

   The flavor-changing neutral current decay processes of the $B$ and $B_c$ mesons with the final states involving spin-$1/2$ particles are investigated. By considering the background of the Standard Model where $\nu \bar{\nu }$ contributes the missing energy and the experimental upper bounds for the branching fractions, we get the constraints of the coupling constants of the quark-antiquark and the assumed invisible particles $\chi \bar{\chi }$. The constraints of the coupling constants are then used to study the similar processes of the $B_c$ meson. At some specific region of $m_{\chi }$, the upper limit of BR($B_c\to D_{(s)}\chi \bar{\chi }$) is of the order of $10^{-6}$, while for BR($B_c\to D_{(s)}^{\ast }\chi \bar{\chi }$), it is $10^{-5}$. The possibility of distinguishing $\chi$ to be a Majorana or Dirac fermion by the differential branching fractions is also discussed.

   hep-phPRD(2020)·12 citations
3. 03*

   $Y(4626)$ as a $P$-wave $[cs][\bar{c}\bar{s}]$ tetraquark state

   Jian-Rong Zhang🇨🇳

   Motivated by the Belle Collaboration's new observation of $Y(4626)$, we investigate the possibility of its configuration as a $P$-wave $[cs][\bar{c}\bar{s}]$ tetraquark state from QCD sum rules. Eventually, the extracted mass $4.60_{-0.19}^{+0.13}\text{mbox}GeV$ for the $P$-wave $cs$-scalar-diquark $\bar{c}\bar{s}$-scalar-antidiquark state agrees well with the experimental data of $Y(4626)$, which could support its interpretation as a $P$-wave scalar-scalar $[cs][\bar{c}\bar{s}]$ tetraquark state.

   hep-phhep-exPRD(2020)·9 citations
4. 04*

   DUNE prospect for leptophobic dark matter

   Sabeeha Naaz🇮🇳 · Jyotsna Singh🇮🇳 · R. B. Singh🇮🇳

   Highly energetic proton/electron beam fixed target experiments extends an opportunity to probe the sub-GeV dark matter and associated interactions. In this work we have explored the sensitivity of DUNE for sub-GeV leptophobic dark matter i.e. this dark matter barely couples with the leptons. Baryon number gauge theory can predicts the existence of a leptophobic cold dark matter particle candidates. In our work, the dark matter candidate is considered to be scalar whose mass is defined by the symmetry breaking of new baryonic gauge group $U(1{)}_B$. In this scenario a light scalar dark matter couples with the standard model candidates via vector boson mediator $V_B$ which belongs to the baryonic gauge group $U(1{)}_B$. This leptophobic dark matter dominantly couples to the quarks. Under this scenario new parameter space for ${\alpha }_B$ is explored by DUNE for leptophobic dark matter candidates. This new parameter space allowed ${\alpha }_B$ to get lower value than the present exiting constraint value of ${\alpha }_B$ i.e. $10^{-6}$.

   hep-phAdv.High Energy Phys.(2020)·5 citations
5. 05*

   Data-driven study of the implications of anomalous magnetic moments and lepton flavor violating processes of $e$, $\mu$ and $\tau$

   Chun-Khiang Chua🇹🇼

   We study anomalous magnetic moments and flavor violating processes of $e$, $\mu$ and $\tau$ leptons. We use a data driven approach to investigate the implications of the present data on the parameters of a class of models, which has spin-0 scalar and spin-1/2 fermion fields. We compare two different cases, which has or does not have a built-in cancelation mechanism. Our findings are as following. Chiral interactions are unable to generate large enough $\Delta a_e$ and $\Delta a_{\mu }$ to accommodate the experimental results. Sizable $\Delta a_e$ and $\Delta a_{\mu }$ can be generated from non-chiral interactions, but they are not contributed from the same source. The upper limit of $\mu \to e\gamma$ decay gives the most severe constraints on photonic penguin contributions in $\mu \to e$ transitions, but the situation may change in considering future experimental sensitivities. The $Z$-penguin diagrams can constrain chiral interaction better than photonic penguin diagrams in $\mu \to e$ transitions. In most of the parameter space, box contributions to $\mu \to 3e$ decay are subleading. In $\tau \to e$ $(\mu )$ transitions, the present $\tau \to e\gamma$ $(\mu \gamma )$ upper limit constrains the photonic penguin contribution better than the $\tau \to 3e$ $(3\mu )$ upper limit, and $Z$-penguin amplitudes constrain chiral interaction better than photonic penguin amplitudes. Box contributions to $\tau \to 3e$ and $\tau \to 3\mu$ decays can sometime be comparable to $Z$-penguin contributions. The ${\tau }^{-}\to e^{-}{\mu }^{+}{e}^{-}$ and ${\tau }^{-}\to {\mu }^{-}{e}^{+}{\mu }^{-}$ rates are highly constrained by $\tau \to e\gamma$, $\mu \to e\gamma$ and $\tau \to \mu \gamma$, $\mu \to e\gamma$ upper limits, respectively. We compare the current experimental upper limits, future sensitivities and bounds from consistency on various muon and tau LFV processes.

   hep-phPRD(2020)·13 citations
6. 06*

   The Supersymmetric $(B-L)$ model with three non-identical right-handed neutrinos

   M. C. Rodriguez🇧🇷

   We build a supersymmetric version with $SU(3{)}_C\otimes SU(2{)}_L\otimes U(1{)}_{Y^{\prime }}\otimes U(1{)}_{(B-L)}$ gauge symmetry, where $Y^{\prime }$ is a new charge and ($B$) and ($L$) are the usual baryonic and leptonic numbers, respectivelly. The model has three right-handed neutrinos with non identical $(B-L)$ charges. We will use the superfield formalism in order to build our lagrangian and it is possible to accommodate all fermion masses at the tree level. In particular, the type-I seesaw mechanism is implemented for the generation of the active neutrino masses and also explain the mixing angle at the fermion sector. There are good candidates to Dark Matter, it can be the lighest righ-handed neutrinos or lighest right-handed sneutrinos or the lighest usual scalar field and due a Majorana phase at sneutrinos right-handed masses, it can induce Leptogenesis in this model.

   hep-phInt.J.Mod.Phys.A(2021)·4 citations
7. 07*

   Momentum broadening of heavy quark in a magnetized thermal QCD medium

   Balbeer Singh🇮🇳 · Manu Kurian🇮🇳 · Surasree Mazumder🇮🇳 · Hiranmaya Mishra🇮🇳 · Vinod Chandra🇮🇳 · Santosh K. Das🇮🇳

   Anisotropic momentum diffusion coefficients of heavy quarks have been computed in a strongly magnetized quark-gluon plasma beyond the static limit within the framework of Langevin dynamics. Depending on the orientation of the motion of the heavy quark with respect to the direction of the magnetic field, five momentum diffusion coefficients of heavy quark have been estimated in the magnetized thermal medium. Specifically, we have focussed our attention to temperature range and strength of magnetic field satisfying the condition, $i.e.$ $M\gg \sqrt{eB}\gg T$, $M$ being the mass of heavy quark. The light quarks/antiquarks follow $1+1-$dimensional lowest Landau level (LLL) kinematics, and heavy quark dynamics are not directly affected by the magnetic field in the medium. The thermal gluon contribution to the diffusion coefficient is proportions to $T^3$, whereas, the contribution of light quarks in the lowest Landau state to the same is seen to be proportional to $T|eB|$. Furthermore, it is observed that for the case of heavy quark motion parallel to the magnetic field, the component of diffusion coefficient transverse both to the field and the heavy quark velocity $({\kappa }_{TT}^{\parallel })$ turns out to be dominant as compared to the component longitudinal to both the field and motion $({\kappa }_{LL}^{\parallel })$, $i.e.$, ${\kappa }_{TT}^{\parallel }\gg {\kappa }_{LL}^{\parallel }$. Further, for the case of heavy quark moving perpendicular to the magnetic field, it is seen that the diffusion coefficients transverse to the magnetic field are dominant, i.e., ${\kappa }_{LT}^{\perp },{\kappa }_{TT}^{\perp }\gg {\kappa }_{TL}^{\perp }$.

   hep-ph17 citations
8. 08*

   Toward establishing the low-lying $P$-wave ${\Sigma }_b$ states

   Li-Ye Xiao🇨🇳 · Xian-Hui Zhong🇨🇳

   In the present work, we analyze the $P$-wave singly-heavy baryon spectrum belonging to $6_F$ by combining the observations of the heavy baryon states, and restudy the strong decays of the $1P$ wave ${\Sigma }_b$ states within the $j$-$j$ coupling scheme using the chiral quark model. We obtain that: (i) the structure ${\Sigma }_b(6097)$ observed in the ${\Lambda }_b\pi$ final state may arise from the overlapping of ${\Sigma }_b|J^P={\frac{3}{2}}^{-},2⟩$ and ${\Sigma }_b|J^P={\frac{5}{2}}^{-},2⟩$. (ii) The broad structure ${\Sigma }_b(6072)$ observed in the ${\Lambda }_b\pi \pi$ final state may arise from the overlapping of ${\Sigma }_b|J^P={\frac{1}{2}}^{-},1⟩$ and ${\Sigma }_b|J^P={\frac{3}{2}}^{-},1⟩$. (iii) The missing state ${\Sigma }_b|J^P={\frac{1}{2}}^{-},0⟩$ is most likely to be a narrow state with a width of $\Gamma \sim 10$ MeV, and mainly decays into ${\Lambda }_b\pi$ channel.

   hep-phPRD(2020)·22 citations
9. 09*

   A Study of New Physics Searches with Tritium and Similar Molecules

   Wolfgang Gregor Hollik🇩🇪 · Matthias Linster🇩🇪 · Mustafa Tabet🇩🇪

   Searches for New Physics focus either on the direct production of new particles at colliders or at deviations from known observables at low energies. In order to discover New Physics in precision measurements, both experimental and theoretical uncertainties must be under full control. Laser spectroscopy nowadays offers a tool to measure transition frequencies very precisely. For certain molecular and atomic transitions the experimental technique permits a clean study of possible deviations. Theoretical progress in recent years allows us to compare ab initio calculations with experimental data. We study the impact of a variety of New Physics scenarios on these observables and derive novel constraints on many popular generic Standard Model extensions. As a result, we find that molecular spectroscopy is not competitive with atomic spectroscopy and neutron scattering to probe new electron-nucleus and nucleus-nucleus interactions, respectively. Molecular and atomic spectroscopy give similar bounds on new electron-electron couplings, for which, however, stronger bounds can be derived from the magnetic moment of the electron. In most of the parameter space H_2 molecules give stronger constraints than T_2 or other isotopologues.

   hep-phEPJC(2020)·8 citations
10. 10*

    Crossed two Higgs-doublet models: reduction of Yukawa parameters in the low-scale limit of left-right symmetry and other avatars

    Gustavo C. Branco🇵🇹 · Dipankar Das🇮🇳 · Miguel Levy🇵🇹 · Palash B. Pal🇮🇳

    We present new variants of the Two Higgs-Doublet Model where all Yukawa couplings with physical Higgs bosons are controlled by the quark mixing matrices of both chiralities, as well as, in one case, the ratio between the two scalar doublets' vacuum expectation values. We obtain these by imposing approximate symmetries on the Lagrangian which, in one of the cases, clearly reveals the model to be the electroweak remnant of the Minimal Left-Right Symmetric Model. We also argue for the benefits of the bidoublet notation in the Two Higgs-Doublet Model context for uncovering new models.

    hep-phPRD(2020)·2 citations
11. 11*

    Prospects of searches for long-lived charged particles with MoEDAL

    B.S. Acharya🇬🇧 · A. De Roeck🇨🇭 · J. Ellis🇬🇧 · D.K. Ghosh🇮🇳 · R. Masełek🇵🇱 · G. Panizzo🇮🇹 · J.L. Pinfold🇨🇦 · K. Sakurai🇵🇱 · A. Shaa🇨🇦 · A. Wall🇺🇸

    We study the prospects of searches for exotic long-lived particles with the MoEDAL detector at the LHC, assuming the integrated luminosity of 30 fb${}^{-1}$ that is expected at the end of Run 3. MoEDAL incorporates nuclear track detectors deployed a few metres away from the interaction point, which are sensitive to any highly-ionizing particles. Hence MoEDAL is able to detect singly- or doubly-charged particles with low velocities $\beta <0.15$ or $<0.3$, respectively, and lifetimes larger than $\mathcal{O}(1)\mathrm{m}/c$. We examine the MoEDAL sensitivity to various singly-charged supersymmetric particles with long lifetimes and to several types of doubly-charged long-lived particles with different spins and SU(2) charges. We compare the prospective MoEDAL mass reaches to current limits from ATLAS and CMS, which involve auxiliary analysis assumptions. MoEDAL searches for doubly-charged fermions are particularly competitive.

    hep-phhep-exEPJC(2020)·31 citations
12. 12*

    Consequences of vector-like quarks of Nelson-Barr type

    A. L. Cherchiglia🇧🇷 · C. C. Nishi🇧🇷

    The Nelson-Barr mechanism to solve the strong CP problem requires vector-like quarks (VLQs) to transmit the spontaneous CP breaking to the SM. We study the scenario where only these VLQs are within reach at the TeV scale while the spontaneous CP breaking sector is inaccessible. We investigate how these VLQs of Nelson-Barr type differ from generic VLQs and find from parameter counting that one less parameter is needed. In particular, for one VLQ of Nelson-Barr type, there is only one CP odd quantity that is responsible for all CP violation. In this case, we solve the technical problem of parametrizing only the new physics parameters while keeping the SM parameters as independent inputs. For one down-type VLQ, the model is largely flavor safe because the VLQ couplings to the SM up quarks and the $W$ are hierarchically smaller for lighter quarks.

    hep-phJHEP(2020)·23 citations
13. 13*

    Higgs-Electroweak Chiral Lagrangian: One-Loop Renormalization Group Equations

    G. Buchalla🇩🇪 · O. Cata🇩🇪 · A. Celis🇩🇪 · M. Knecht🇫🇷 · C. Krause🇺🇸

    Starting from the one-loop divergences we obtained previously, we work out the renormalization of the Higgs-Electroweak Chiral Lagrangian explicitly and in detail. This includes the renormalization of the lowest-order Lagrangian, as well as the decomposition of the remaining divergences into a complete basis of next-to-leading-order counterterms. We provide the list of the corresponding beta functions. We show how our results match the one-loop renormalization of some of the dimension-6 operators in SMEFT. We further point out differences with related work in the literature and discuss them. As an application of the obtained results, we evaluate the divergences of the vacuum expectation value of the Higgs field at one loop and show that they can be appropriately removed by the corresponding renormalization. We also work out the finite renormalization required to keep the no-tadpole condition on the Higgs field at one loop.

    hep-phPRD(2021)·24 citations
14. 14*

    Third-family quark-lepton unification with a fundamental composite Higgs

    Javier Fuentes-Martin🇨🇭 · Peter Stangl🇫🇷

    We present a model for third-family quark-lepton unification at the TeV scale featuring a composite Higgs sector. The model is based on a variant of the Pati-Salam model, the so-called 4321 model, consisting of the gauge group $SU(4)\times SU(3{)}^{\prime }\times SU(2{)}_L\times U(1{)}_X$. The spontaneous symmetry breaking to the SM gauge group is triggered dynamically by a QCD-like confining sector. The same strong dynamics also produces the Higgs as a pseudo Nambu-Goldstone boson, connecting the energy scales of both sectors. The model predicts a massive $U_1$ vector leptoquark coupled dominantly to the third generation, recently put forward as a possible solution to the $B$-meson anomalies.

    hep-phPLB(2020)·99 citations
15. 15*

    Rethinking Jets with Energy Correlators: Tracks, Resummation and Analytic Continuation

    Hao Chen🇨🇳 · Ian Moult🇺🇸 · XiaoYuan Zhang🇨🇳 · Hua Xing Zhu🇨🇳

    We introduce an infinite set of jet substructure observables, derived as projections of $N$-point energy correlators, that are both convenient for experimental studies and maintain remarkable analytic properties derived from their representations in terms of a finite number of light ray operators. We show that these observables can be computed using tracking or charge information with a simple reweighting by integer moments of non-perturbative track or fragmentation functions. Our results for the projected $N$-point correlators are analytic functions of $N$, allowing us to derive resummed results to next-to-leading logarithmic accuracy for all $N$. We analytically continue our results to non-integer values of $N$ and define a corresponding analytic continuation of the observable, which we term a $\nu$-correlator, that can be measured on jets of hadrons at the LHC. This enables observables that probe the leading twist collinear dynamics of jets to be placed into a single analytic family, which we hope will lead to new insights into jet substructure.

    hep-phhep-thnucl-thPRD(2020)·221 citations
16. 16*

    Gravitational wave background from Standard Model physics: Complete leading order

    J. Ghiglieri🇫🇷 · G. Jackson🇨🇭 · M. Laine🇨🇭 · Y. Zhu🇩🇪

    We compute the production rate of the energy density carried by gravitational waves emitted by a Standard Model plasma in thermal equilibrium, consistently to leading order in coupling constants for momenta $k\sim \pi T$. Summing up the contributions from the full history of the universe, the highest temperature of the radiation epoch can be constrained by the so-called $N_{\mathrm{eff}}$ parameter. The current theoretical uncertainty $\Delta N_{\mathrm{eff}}\le 10^{-3}$ corresponds to $T_{\max }\le 2\times 10^{17}$ GeV. In the course of the computation, we show how a subpart of the production rate can be determined with the help of standard packages, even if subsequently an IR subtraction and thermal resummation need to be implemented.

    hep-phastro-ph.COJHEP(2020)·133 citations
17. 17*

    Color dependence of tensor and scalar glueball masses in Yang-Mills theories

    Ed Bennett🇬🇧 · Jack Holligan🇬🇧 · Deog Ki Hong🇰🇷 · Jong-Wan Lee🇰🇷 · C.-J. David Lin🇹🇼 · Biagio Lucini🇬🇧 · Maurizio Piai🇬🇧 · Davide Vadacchino🇮🇹

    We report the masses of the lightest spin-0 and spin-2 glueballs obtained in an extensive lattice study of the continuum and infinite volume limits of $Sp(N_c)$ gauge theories for $N_c=2,4,6,8$. We also extrapolate the combined results towards the large-$N_c$ limit. We compute the ratio of scalar and tensor masses, and observe evidence that this ratio is independent of $N_c$. Other lattice studies of Yang-Mills theories at the same space-time dimension provide a compatible ratio. We further compare these results to various analytical ones and discuss them in view of symmetry-based arguments related to the breaking of scale invariance in the underlying dynamics, showing that a constant ratio might emerge in a scenario in which the $0^{++}$ glueball is interpreted as a dilaton state.

    ↳ hep-lathep-phhep-thPRD(2020)·55 citations
18. 18*

    Thresholds of ultraperipheral processes

    I.M. Dremin🇷🇺

    Threshold behavior of the cross sections of ultraperipheral nuclear interactions is studied. Production of $e^{+}{e}^{-}$ and ${\mu }^{+}{\mu }^{-}$ pairs as well as ${\pi }^0$ and parapositronium is treated. The values of corresponding energy thresholds are presented and the total cross sections of these processes at the newly constructed NICA and FAIR facilities are estimated.

    ↳ nucl-thhep-phInt.J.Mod.Phys.A(2020)·2 citations
19. 19*

    New result on phase shift analysis

    André Martin (CERN)🇨🇭 · Jean-Marc Richard (IP2I, Lyon, France)🇫🇷

    Assuming a certain continuity property, we prove, using the old results of Itzykson and Martin, that, except for an obvious ambiguity, there are only at most two amplitudes reproducing an elastic differential cross section at a given energy.

    ↳ math-phhep-phmath.MPquant-phPRD(2020)·9 citations
20. 20*

    Astrophysics in the Laboratory: The CBM Experiment at FAIR

    P. Senger · for the CBM collaboration

    The future Facility for Antiproton and Ion Research (FAIR) is an accelerator-based international center for fundamental and applied research, which presently is under construction in Darmstadt, Germany. An important part of the program is devoted to questions related to astrophysics, including the origin of elements in the universe and the properties of strongly interacting matter under extreme conditions, which are relevant for our understanding of the structure of neutron stars and the dynamics of supernova explosions and neutron star mergers. The Compressed Baryonic Matter (CBM) experiment at FAIR is designed to measure promising observables in high-energy heavy-ion collisions, which are expected to be sensitive to the high-density equation-of-state (EOS) of nuclear matter and to new phases of QCD matter at high densities. The CBM physics program, the relevant observables and the experimental setup will be discussed.

    ↳ nucl-exastro-ph.IMhep-exhep-ph+1Particles(2020)·15 citations
21. 21*

    The geometry and environment of repeating FRBs

    Shuang Du🇨🇳 · Weihua Wang🇨🇳 · Xuhao Wu🇨🇳 · Renxin Xu🇨🇳

    We propose a geometrical explanation for periodically and nonperiodically repeating fast radio bursts (FRBs) under neutron star (NS)-companion systems. We suggest a constant critical binary separation, $r_{\mathrm{c}}$, within which the interaction between the NS and companion can trigger FRB bursts. For an elliptic orbit with the minimum and maximum binary separations, $r_{\min }$ and $r_{\max }$, a periodically repeating FRB with an active period could be reproduced if $r_{\min }<r_{\mathrm{c}}<r_{\max }$. However, if $r_{\max }<r_{\mathrm{c}}$, the modulation of orbital motion will not work due to persistent interaction, and this kind of repeating FRBs should be nonperiodic. We test relevant NS-companion binary scenarios on the basis of FRB 180916.J0158+65 and FRB 121102 under this geometrical frame. It is found that the pulsar-asteroid belt impact model is more suitable to explain these two FRBs since this model is compatible with different companions (e.g., massive stars and black holes). At last, we point out that FRB 121102-like samples are potential objects which can reveal the evolution of star-forming region.

    ↳ astro-ph.HEhep-phMNRAS(2020)·12 citations
22. 22*

    Superradiant pion clouds around primordial black holes

    Paulo B. Ferraz🇵🇹 · Thomas W. Kephart🇺🇸 · João G. Rosa🇵🇹

    We show that highly spinning primordial black holes of mass $M\sim 10^{12}$ kg, potentially born in a matter-dominated era after inflation, can produce clouds of pions in their vicinity via the superradiant instability, with densities up to that of nuclear matter. We discuss the electromagnetic signatures of this process, via neutral pion decay and charged pion annihilation into photons, computing in particular their contribution to the isotropic gamma-ray background. This allows us to place upper bounds on the abundance of such primordial black holes that are comparable to the ones obtained from Hawking evaporation. We also discuss the possibility of directly observing such clouds in high-redshift superclusters.

    ↳ gr-qcastro-ph.COhep-phJCAP(2022)·29 citations
23. 23*

    SENSEI: Direct-Detection Results on sub-GeV Dark Matter from a New Skipper-CCD

    Liron Barak🇮🇱 · Itay M. Bloch🇮🇱 · Mariano Cababie🇦🇷 · Gustavo Cancelo🇺🇸 · Luke Chaplinsky🇺🇸 · Fernando Chierchie🇺🇸 · Michael Crisler🇺🇸 · Alex Drlica-Wagner🇺🇸 · Rouven Essig🇺🇸 · Juan Estrada🇺🇸 · Erez Etzion🇮🇱 · Guillermo Fernandez Moroni🇺🇸 and 11 other authors

    We present the first direct-detection search for eV-to-GeV dark matter using a new ~2-gram high-resistivity Skipper-CCD from a dedicated fabrication batch that was optimized for dark-matter searches. Using 24 days of data acquired in the MINOS cavern at the Fermi National Accelerator Laboratory, we measure the lowest rates in silicon detectors of events containing one, two, three, or four electrons, and achieve world-leading sensitivity for a large range of sub-GeV dark matter masses. Data taken with different thicknesses of the detector shield suggest a correlation between the rate of high-energy tracks and the rate of single-electron events previously classified as "dark current." We detail key characteristics of the new Skipper-CCDs, which augur well for the planned construction of the ~100-gram SENSEI experiment at SNOLAB.

    ↳ astro-ph.COhep-exhep-phphysics.ins-detPRL(2020)·507 citations
24. 24*

    Lifting the core-collapse supernova bounds on keV-mass sterile neutrinos

    Anna M. Suliga🇩🇰 · Irene Tamborra (Niels Bohr Institute)🇩🇰 · Meng-Ru Wu (Academia Sinica, National Center for Theoretical Sciences)🇹🇼

    We explore the energy and entropy transport as well as the lepton number variation induced from the mixing between electron and sterile neutrinos with keV mass in the supernova core. We develop a radial- and time-dependent treatment of the sterile-electron neutrino mixing, by including ordinary matter effects, reconversions between sterile and electron antineutrinos, as well as the collisional production of sterile particles for the first time. The dynamical feedback due to the production of sterile particles on the composition and thermodynamic properties of the core only leads to major implications for the supernova physics for large mixing angles (${\sin }^{2}2\theta >10^{-10}$). Our findings suggest that a self-consistent appraisal of the electron-sterile conversion physics in the supernova core would relax the bounds on the sterile neutrino mixing parameters reported in the literature for mixing angles smaller than $10^{-6}$, leaving the parameter space of the mass and mixing angles of sterile neutrinos relevant to dark matter searches unconstrained by supernovae.

    ↳ astro-ph.HEhep-phJCAP(2020)·48 citations
25. 25*

    To power the X-ray plateaus of gamma-ray bursts through larger amplitude electromagnetic waves

    Shuang Du🇨🇳

    The origin of gamma-ray burst (GRB) X-ray plateau, especially the internal plateau, is still unclear, but it could be related to GRB's central engine of magnetar. It is generally believed that the spin-down power of the magnetar is injected into forward external shock, however we propose here that most of the power will be dissipated behind the GRB jet through larger amplitude electromagnetic wave (LAEMW). Based on this proposal, the relevant physical conditions and observational implications are analyzed and discussed, and various kinds of X-ray light curves could be reproduced. Although it is still a matter of debate about the chromatic multi-band afterglow in the standard external afterglow fireball model, we can explain naturally this feature under this proposal, i.e., the electrons generating the X-ray plateau and emitting the optical afterglow are accelerated by different mechanisms. %Furthermore, we predict that the X-ray emission of spin-down wind could possibly precede the prompt emission of GRB jet if the energy of LAEMW is dissipated first but shock-induced radiation in the jet is produced later. It is emphasized that both the GRB jet and the spin-down wind should have significant observational consequences in the magnetar scenario, and should be focused equally in GRB physics.

    ↳ astro-ph.HEhep-phApJ(2020)·9 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.