Wed·May 18, 2022Wednesday·May 18, 2022

1. 01*

   Constraining the top electroweak sector of the SMEFT through $Z$ associated top pair and single top production at the HL-LHC

   Rahool Kumar Barman🇺🇸 · Ahmed Ismail🇺🇸

   We study the processes $pp\to t\bar{t}Z$ and $pp\to tZj$ in the framework of Standard Model Effective Field Theory (SMEFT), employing conventional cut-and-count as well as machine learning techniques to take advantage of kinematic information in complex final states involving multiple leptons and $b$ jets. We explore the projected sensitivity for two SMEFT operators, ${\mathcal{O}}_{tZ}$ and ${\mathcal{O}}_{tW}$, that induce electroweak dipole moment interactions for top quarks, through direct searches in these electroweak top production processes at the HL-LHC. New physics modifications to dominant backgrounds are also considered. We show that the new physics sensitivity can be enhanced through a combination of differential distributions for relevant kinematic observables and machine learning techniques. Searches in $t\bar{t}Z$ and $tZj$ production result in stronger constraints on ${\mathcal{C}}_{tZ}$ and ${\mathcal{C}}_{tW}$, respectively. At the HL-LHC, ${\mathcal{C}}_{tZ}$ can be probed up to $-0.41\lesssim {\mathcal{C}}_{tZ}\lesssim 0.47$ through searches in the $pp\to t\bar{t}Z+tWZ\to 3\ell +2b+\ge 2j$ channel while ${\mathcal{C}}_{tW}$ can be probed up to $-0.14\lesssim {\mathcal{C}}_{tW}<0.11$ from searches in the $pp\to tZj+t\bar{t}Z+tWZ\to 3\ell +1b+1/2j$ channel, at $95\%$ CL.

   hep-ph10 citations
2. 02*

   Nested Radiative Seesaw Masses for Dark Matter and Neutrinos

   Talal Ahmed Chowdhury🇧🇩 · Shaaban Khalil🇪🇬 · Ernest Ma🇺🇸

   The scotogenic model of neutrino mass is modified so that the dark Majorana fermion singlet $S$ which makes the neutrino massive is itself generated in one loop. This is accomplished by having $Z_6$ lepton symmetry softly broken to $Z_2$ in the scalar sector by a unique quadratic term. It is shown that $S$ is a viable freeze-in dark-matter candidate through Higgs decay.

   hep-phPRD(2022)·0 citations
3. 03*

   Enhanced EDMs from Small Instantons

   Ravneet S. Bedi🇺🇸 · Tony Gherghetta🇺🇸 · Maxim Pospelov🇺🇸

   We show that models in which the strong $CP$ problem is solved by introducing an axion field with a mass enhanced by non-QCD UV dynamics at a scale ${\Lambda }_{\mathrm{SI}}$ exhibit enhanced sensitivity to external sources of $CP$ violation. In the presence of higher-dimensional $CP$-odd sources at a scale ${\Lambda }_{\mathrm{CP}}$, the same mechanisms that enhance the axion mass also modify the axion potential, shifting the potential minimum by a factor $\propto {\Lambda }_{\mathrm{SI}}^2/{\Lambda }_{\mathrm{CP}}^2$. This phenomenon of $CP$-violation enhancement, which puts stringent constraints on the scale of new physics, is explicitly demonstrated within a broad class of "small instanton" models with $CP$-odd sources arising from the dimension-six Weinberg gluonic and four-fermion operators. We find that for heavy axion masses $\gtrsim 100$MeV, arising from new dynamics at ${\Lambda }_{\mathrm{SI}}\lesssim 10^{10}$GeV, $CP$ violation generated up to the Planck scale can be probed by future electric dipole moment experiments.

   hep-phPRD(2022)·22 citations
4. 04*

   Semi-inclusive Diffractive Deep Inelastic Scattering at Small-$x$

   Yoshitaka Hatta🇺🇸 · Bo-Wen Xiao🇨🇳 · Feng Yuan🇺🇸

   Inspired by a recent study of Iancu, Mueller and Triantafyllopoulos [1] and earlier papers by Golec-Biernat and Wusthoff [2,3], we propose semi-inclusive diffractive deep inelastic scattering (SIDDIS) to investigate the gluon tomography in the nucleon and nuclei at small-$x$. The relevant diffractive quark and gluon parton distribution functions (DPDF) can be computed in terms of the color dipole S-matrices in the fundamental and adjoint representations, respectively. Novel correlations from the gluon tomography in the dipole S-matrix can be experimentally studied through the DPDFs in these processes at the future electron-ion collider (EIC).

   hep-phhep-exnucl-exnucl-thPRD(2022)·62 citations
5. 05*

   Linear Sigma Dark Matter

   Dan Kondo🇯🇵 · Robert McGehee🇺🇸 · Tom Melia🇯🇵 · Hitoshi Murayama🇺🇸

   We present a model of self-interacting dark matter based on QCD-like theories and inspired by the proximity of $a_0(980\pm 20)$ to the $K\bar{K}(990)$ threshold. Dark matter is comprised of dark pions which self-scatter via the $\sigma$ resonance close to the $\pi \pi$ threshold. While the linear sigma model serves as a qualitative guide, a fully unitary description of the scattering in the strongly coupled regime is given by effective range theory. The introduction of a kinetically mixed dark photon allows the dark pion to either freeze-out or -in. We study the viable parameter space which explains the observed relic abundance while evading all current constraints. Searches for dark matter self interactions at different scales, (in)direct detection signals, and (in)visibly-decaying dark photons will test this model in the near future.

   hep-phastro-ph.COJHEP(2022)·35 citations
6. 06*

   Nonlinear corrections to the single differential cross section for neutral current e-p scattering at the NLO approximation

   S. Zarrin🇮🇷 · S. Dadfar (Department of Physics, University of Sistan and Baluchestan, Zahedan, Iran)🇮🇷

   We present the effects of nonlinear corrections to the single differential cross section d\sigma/dQ^2 and the reduced cross section \sigma_r (x,Q^2) for the neutral current (NC) e-p scattering at the leading order (LO) and the next-to-leading order (NLO) approximations in perturbative quantum chromo dynamics (QCD). Technically, based on the double Laplace transform method, we first derive the effects of the nonlinear corrections to the proton structure functions F2(x,Q^2) and FL(x,Q^2) and consequently obtain the corresponding single differential and reduced cross sections. Our results clearly indicate the consistency of the nonlinear behavior of the quark and gluon distributions at low x values. Our numerical results ( obtained in a range of the virtuality 8.5 < Q2 < 5000 GeV ^2 and the Bjorken scale 10^(-5)< x < 1) show that the effects of these nonlinear corrections to the proton structure functions are more noticeable at x < 0.001 and, to some extent, control the incremental trend of these functions at low x values. Moreover, a comparison of our numerical results of the single differential and reduced cross sections at the NLO approximations with those of H1 collaboration data shows that the nonlinear corrections increase the accuracy of calculations rather than the linear calculations at low to moderate Q^2 values for low x values.

   hep-phPRD(2022)·2 citations
7. 07*

   Decays of a bino-like particle in the low-mass regime

   Florian Domingo🇩🇪 · Herbi K. Dreiner🇩🇪

   We study the phenomenology associated with a light bino-like neutralino with mass under the tau mass in the context of the R-parity violating Minimal Supersymmetric Standard Model. This is a well-motivated example of scenarios producing potentially light and long-lived exotic particles, which might be testable in far-detector experiments, such as the FASER experiment at the Large Hadron Collider. A quantitative assessment of the discovery potential or the extraction of limits run through a detailed understanding of the interactions of the light exotic fermion with Standard Model matter, in particular, the hadronic sector. Here, we propose a systematic analysis of the decays of such a particle and proceed to a model-independent derivation of the low-energy effects, so that this formalism may be transposed to other UV-completions or even stand as an independent effective field theory. We then stress the diversity of the possible phenomenology and more specifically discuss the features associated with the R-parity violating supersymmetric framework, for example neutron-antineutron oscillations.

   hep-phSciPost Phys.(2023)·16 citations
8. 08*

   Center of mass motion in bag model

   Chia-Wei Liu🇨🇳 · Chao-Qiang Geng🇨🇳

   Despite the great success on the mass spectra, the reputation of the bag model has been closely followed by the embarrassment from the center of mass motion. It leads to severe theoretical inconsistencies. For instance, the masses and the decay constants would no longer be independent of the momentum. In this work, we provide a systematical approach to resolve this problem. The meson decay constants as well as the baryon transition form factors can be computed consistently in our framework. Notably, the form factors in the neutron $\beta$ decays do not depend on any free parameters, and are determined to be $F_1^V=1$ and $F_1^A=1.31$ or $F_1^A/F_1^V=1.31$, which is close the experimental value of $F_1^A/F_1^V=1.27$. In addition, we find that $\mathcal{B}({\Lambda }_b\to \Lambda \gamma )=(6.8\pm 3.3)\times 10^{-6}$, which agrees to the experimental value of $(7.1\pm 1.7)\times 10^{-6}$.

   hep-phCPC(2023)·18 citations
9. 09*

   Restriction on the form of quark anomalous magnetic moment from lattice QCD results

   Mamiya Kawaguchi🇨🇳 · Mei Huang🇨🇳

   The quark anomalous magnetic moment (AMM) is dynamically generated through the spontaneous chiral symmetry breaking. It has been revealed that even though its exact form is still unknown, the quark AMM is essential to explore quark matter properties and QCD phase structure under external magnetic fields. In this study, we take three different forms of the quark AMM and investigate its influence on the chiral phase transition under magnetic field. In general, a negative quark AMM plays the role as magnetic catalyzer and a positive quark AMM plays the role of magnetic inhibition. It is found that a constant quark AMM drives an unexpected 1st order chiral phase transition; a quark AMM proportional to the chiral condensate gives a flip of the sign on the chiral condensate; and a quark AMM proportional to the square of chiral condensate can produce results of chiral condensate as functions of the temperature and the magnetic field in good agreement with the lattice result.

   hep-phhep-latnucl-thCPC(2023)·19 citations
10. 10*

    Confronting the Galactic 511 keV emission with $B-L$ gauge boson dark matter

    Weikang Lin🇨🇳 · Tsutomu Yanagida🇨🇳

    The $B-L$ gauge symmetry motivated from the successful generation of the seesaw mechanism and leptogenesis. We show that if the $B-L$ gauge boson constitutes a small fraction of the dark matter (DM) it can explain the Galactic $511$ keV emission via the decay into an electron-positron pair. We find the model parameter space that is consistent with the seesaw mechanism, cosmologically viable, and accounting for the amplitude of the Galactic positron line. From this parameter space we derive an upper bound of the gauge boson mass and then an bound of the positron injection energy $\lesssim 3$ MeV. This derived energy bound is consistent with the observational upper limit of the injection energy. The resultant model predicts the $B-L$ breaking scale to be in a relatively narrow range, i.e., $V_{B\text{–}L}\sim 10^{15}\text{–}10^{16}$GeV, which is consistent with a Grand Unification (GUT) scale seesaw mechanism. The model is consistent in several phenomenologies, suggesting their common origin from the B-L symmetry breaking.

    hep-phastro-ph.COastro-ph.HEPRD(2022)·8 citations
11. 11*

    Shedding light on the electroweak phase transition from exotic Higgs boson decays at the lifetime frontiers

    Wei Liu🇨🇳 · Aigeng Yang🇨🇳 · Hao Sun🇨🇳

    We study the scenarios where a strongly first-order electroweak phase transition (EWPT) is triggered by a light singlet scalar, which has feeble interactions to the Higgs. Since the singlet scalar is light and has weak couplings, it can decay at a macroscopic distance away from the collision point. Therefore, it can be regarded as a long-lived particles (LLP) in such scenarios. We perform the searches of the LLPs from the exotic Higgs decays, at the FASER, MAPP and CMS-Timing detectors of the 14 TeV HL-LHC, to probe the strongly first-order EWPT. In certain scenarios, we show that the LLP searches can help to reach the parameter space of the strongly first-order EWPT remarkably, where the searches for promptly exotic Higgs decays are not valid.

    hep-phPRD(2022)·10 citations
12. 12*

    Explanations of the Tentative New Physics Anomalies and Dark Matter in the Simple Extension of the Standard Model (SESM)

    Tianjun Li🇨🇳 · Junle Pei🇨🇳 · Xiangwei Yin🇨🇳 · Bin Zhu🇨🇳

    We revisit the Simple Extension of the Standard Model (SESM), which can account for various tentative new physics anomalies and dark matter. The B physics anomalies, muon anomalous magnetic moment, and dark matter can be explained already in SESM. In this work, we study the unitarity constraint on this model and comment the parameter space on the edge of unitarity bounds. Besides, the complete scalar potential is considered which is needed to address the $W$ boson anomaly and more dark matter (co-)annihilation processes are discussed. We perform a systematic study, and find the viable parameter space which can explain these anomalies and evade all the current experimental constraints.

    hep-phNPB(2024)·5 citations
13. 13*

    NNLO anomalous dimension matrix for twist-two flavor-singlet operators

    V.M. Braun🇩🇪 · K.G. Chetyrkin🇩🇪 · A.N. Manashov🇩🇪

    Conformal symmetry of QCD is restored at the Wilson-Fisher critical point in noninteger $4-2ϵ$ space-time dimensions. Correlation functions of multiplicatively renormalizable operators with different anomalous dimensions at the critical point vanish identically. We show that this property allows one to calculate off-diagonal parts of the anomalous dimension matrices for leading-twist operators from a set of two-point correlation functions of gauge-invariant operators which can be evaluated using standard computer algebra techniques. As an illustration, we present the results for the NNLO anomalous dimension matrix for flavor-singlet QCD operators for spin $N\le 8$.

    hep-phPLB(2022)·10 citations
14. 14*

    Natural mass hierarchy among three heavy Majorana neutrinos for resonant leptogenesis under modular $A_4$ symmetry

    Dong Woo Kang🇰🇷 · Jongkuk Kim🇰🇷 · Takaaki Nomura🇨🇳 · Hiroshi Okada🇰🇷

    It is clear that matter is dominant in the Universe compared to antimatter. We call this problem baryon asymmetry. The baryon asymmetry is experimentally determined by both cosmic microwave background and big bang nucleosynthesis measurements. To resolve the baryon number asymmetry of the Universe as well as neutrino oscillations, we study a radiative seesaw model in a modular $A_4$ symmetry. Degenerate heavy Majorana neutrino masses can be naturally realized in an appropriate assignments under modular $A_4$ with large imaginary part of modulus $\tau$, and it can induce measured baryon number via resonant leptogenesis that is valid in around TeV scale energy theory. We also find that the dominant contribution to the CP asymmetry arises from Re[$\tau$] through our numerical analysis satisfying the neutrino oscillation data.

    hep-phJHEP(2022)·28 citations
15. 15*

    Stability of Classical Chromodynamic Fields -- Addendum

    Sylwia Bazak🇵🇱 · Stanislaw Mrowczynski🇵🇱

    A system of chromodynamic fields, which can be treated as classical, is generated at the earliest stage of relativistic heavy-ion collisions. Numerical simulations show that the system is unstable but the nature of the instability is not well understood. We study the problem systematically. In the first paper, we have performed a linear stability analysis of space-time uniform chromoelectric and chromomagnetic fields. There they have been considered the Abelian configurations of single-color potentials linearly depending on coordinates and nonAbelian ones where the fields are generated by the multi-color non-commuting uniform potentials. Here we extend and supplement the analysis. We discuss the parallel chromoelectric and chromomagnetic fields which occur simultaneously. We also consider a general nonAbelian configurations of the uniform fields. Finally, we discuss the gauge dependence of our results.

    hep-phnucl-thPRD(2022)·5 citations
16. 16*

    A Stringy Model of Pointlike Particles

    Risto Raitio🇫🇮

    A previous supersymmetric preon scenario for visible matter particles is extended to the dark sector. In addition, the scenario is reformulated as a Double Field Theory (DFT) with four extra dimensions, to avoid a singular Big Bang in cosmology. T-duality and doubled local Lorentz symmetry of the model are genuine stringy properties. It is proposed that DFT preons may be an approximate pointlike projection of string theory.

    hep-phhep-thNPB(2022)·2 citations
17. 17*

    Probing WIMPs in space-based gravitational wave experiments

    Bo-Qiang Lu🇨🇳 · Cheng-Wei Chiang🇹🇼 · Da Huang🇨🇳

    Although searches for dark matter have lasted for decades, no convincing signal has been found without ambiguity in underground detections, cosmic ray observations, and collider experiments. We show by example that gravitational wave (GW) observations can be a supplement to dark matter detections if the production of dark matter follows a strong first-order cosmological phase transition. We explore this possibility in a complex singlet extension of the standard model with CP symmetry. We demonstrate three benchmarks in which the GW signals from the first-order phase transition are loud enough for future space-based GW observations, for example, BBO, U-DECIGO, LISA, Taiji, and TianQin. While satisfying the constraints from the XENON1T experiment and the Fermi-LAT gamma-ray observations, the dark matter candidate with its mass around $\sim 1$~TeV in these scenarios has a correct relic abundance obtained by the Planck observations of the cosmic microwave background radiation.

    hep-phPLB(2022)·8 citations
18. 18*

    Cosmology-friendly time-varying neutrino masses via the sterile neutrino portal

    Guo-yuan Huang🇩🇪 · Manfred Lindner🇩🇪 · Pablo Martínez-Miravé🇪🇸 · Manibrata Sen🇩🇪

    We investigate a consistent scenario of time-varying neutrino masses, and discuss its impact on cosmology, beta decay, and neutrino oscillation experiments. Such time-varying masses are assumed to be generated by the coupling between a sterile neutrino and an ultralight scalar field, which in turn affects the light neutrinos by mixing. Besides, the scalar could act as an ultralight dark matter candidate. We demonstrate how various cosmological bounds, such as those coming from Big Bang nucleosynthesis, the cosmic microwave background, as well as large scale structures, can be evaded in this model. This scenario can be further constrained using multiple terrestrial experiments. In particular, for beta-decay experiments like KATRIN, non-trivial distortions to the electron spectrum can be induced, even when time-variation is fast and gets averaged out. Furthermore, the presence of time-varying masses of sterile neutrinos will alter the interpretation of light sterile neutrino parameter space in the context of the reactor and gallium anomalies. In addition, we also study the impact of such time-varying neutrino masses on results from the BEST collaboration, which have recently strengthened the gallium anomaly. If confirmed, we find that the time-varying neutrino mass hypothesis could give a better fit to the recent BEST data.

    hep-phastro-ph.COhep-exPRD(2022)·43 citations
19. 19*

    Structure of exotic hadrons by a weak-binding relation with finite-range correction

    Tomona Kinugawa🇯🇵 · Tetsuo Hyodo🇯🇵

    The composite nature of a shallow bound state is studied by using the weak-binding relation, which connects the compositeness of the bound state with observables. We first show that the previous weak-binding relation cannot be applied to the system with a large effective range. To overcome this difficulty, we introduce the finite-range correction by redefining the typical length scale in the weak-binding relation. A method to estimate the uncertainty of the compositeness is proposed. It is numerically demonstrated that the range correction enlarges the applicable region of the weak-binding relation. Finally, we apply the improved weak-binding relation to the actual hadrons, nuclei, and atomic systems [deuteron, $X(3872)$, $D_{s0}^{\ast }(2317)$, $D_{s1}(2460)$, $N\Omega$ dibaryon, $\Omega \Omega$ dibaryon, ${}_{\Lambda }^3\mathrm{H}$, and ${}^4\mathrm{He}$ dimer] to discuss their internal structure from the compositeness. We present a reasonable estimation of the compositeness of the deuteron by properly taking into account the uncertainty. The results of $X(3872)$ and the $N\Omega$ dibaryon show that the range correction is important to estimate the compositeness of physical states.

    hep-phnucl-thPRC(2022)·23 citations
20. 20*

    Tree level Majorana neutrino mass from Type-1 $\times$ Type-2 Seesaw mechanism with Dark Matter

    Chi-Fong Wong🇨🇳 · Yang Chen🇺🇸

    We propose a type of hybrid Seesaw model that combines Type-1 and Type-2 Seesaw mechanism in multiplicative way to generate tree level Majorana neutrino mass and provides a Dark Matter candidate. The model extends the Standard Model by extra gauge symmetry $U(1{)}_D$ and hidden sector consisted of chiral fermions and additional scalar fields. After spontaneous symmetry breaking, light neutrino masses are generated not only by exchange of the new heavy fermions as Type-1 Seesaw, but also by coupling to the naturally small induced vacuum expectation value of new heavy scalar as Type-2 Seesaw. An unbroken residue of $U(1{)}_D$ protects the lightest Dirac fermion required by anomaly cancellation in hidden sector from decaying, therefore giving rise to a Dark Matter candidate. Due to strong enough Seesaw suppression from our hybridization, new physics scale can be as low as TeV in this model and discovering signal from LHC data is possible in near future.

    hep-phPLB(2022)·8 citations
21. 21*

    The Physics potential of the CEPC. Prepared for the US Snowmass Community Planning Exercise (Snowmass 2021)

    Huajie Cheng🇨🇳 · Wen Han Chiu🇺🇸 · Yaquan Fang🇨🇳 · Yu Gao🇨🇳 · Jiayin Gu🇨🇳 · Gang Li🇨🇳 · Lingfeng Li🇺🇸 · Tianjun Li🇨🇳 · Zhijun Liang🇨🇳 · Bo Liu · Jia Liu🇨🇳 · Zhen Liu🇺🇸 and 11 other authors

    The Circular Electron Positron Collider (CEPC) is a large-scale collider facility that can serve as a factory of the Higgs, Z, and W bosons and is upgradable to run at the ttbar threshold. This document describes the latest CEPC nominal operation scenario and particle yields and updates the corresponding physics potential. A new detector concept is also briefly described. This submission is for consideration by the Snowmass process.

    hep-ph139 citations
22. 22*

    Searching for supernova neutrinos with GW memory triggers

    Mainak Mukhopadhyay🇺🇸

    Anisotropic neutrino emission from a core-collapse supernova (CCSN) causes a permanent change in the local space-time metric, called the gravitational wave (GW) memory. Long considered unobservable, this effect will be detectable in the near future, at deci-Hertz GW interferometers. I will present a novel idea, where observations of the neutrino GW memory from CCSNe will enable time-triggered searches of supernova neutrinos at megaton (Mt) scale detectors, which will open a new avenue to studying supernova neutrinos.

    ↳ astro-ph.HEgr-qchep-ph3 citations
23. 23*

    Shaving the Hair of Black Hole with Sagittarius A${}^{\ast }$ from Event Horizon Telescope

    Deng Wang🇨🇳

    Recently, the Event Horizon Telescope collaboration has reported the first image of the supermassive black hole Sagittarius in the Galactic Center. We attempt to test the validity of the no-hair theorem of black holes using this new shadow observation. Considering the Einstein-Maxwell-klein-Gordon theory with a minimally-coupled scalar field, we find that our numerical result is consistent with the prediction of the no-hair theorem. However, we can not rule out the possibility that black holes with scalar hair may exist in some special cases.

    ↳ gr-qchep-ph11 citations
24. 24*

    Gyrohydrodynamics: Relativistic spinful fluid with strong vorticity

    Zheng Cao🇨🇳 · Koichi Hattori🇨🇳 · Masaru Hongo🇯🇵 · Xu-Guang Huang🇨🇳 · Hidetoshi Taya🇯🇵

    We develop a relativistic (quasi-)hydrodynamic framework, dubbed the gyrohydrodynamics, to describe fluid dynamics of many-body systems with spin under strong vorticity based on entropy-current analysis. This framework generalizes the recently-developed spin hydrodynamics to the regime where the spin density is at the leading order in derivatives but suppressed by another small parameter, the Planck constant $\hslash$, due to its quantum nature. Our analysis shows that the complete first-order constitutive relations of gyrohydrodynamics involve seventeen transport coefficients and are highly anisotropic.

    ↳ hep-thhep-phnucl-thPTEP(2022)·56 citations
25. 25*

    A search for two-component Majorana dark matter in a simplified model using the full exposure data of PandaX-II experiment

    Ying Yuan🇨🇳 · Abdusalam Abdukerim🇨🇳 · Zihao Bo🇨🇳 · Wei Chen🇨🇳 · Xun Chen🇨🇳 · Yunhua Chen🇨🇳 · Chen Cheng🇨🇳 · Xiangyi Cui🇨🇳 · Yingjie Fan🇨🇳 · Deqing Fang🇨🇳 · Changbo Fu🇨🇳 · Mengting Fu🇨🇳 and 66 other authors

    In the two-component Majorana dark matter model, one dark matter particle can scatter off the target nuclei, and turn into a slightly heavier component. In the framework of a simplified model with a vector boson mediator, both the tree-level and loop-level processes contribute to the signal in direct detection experiment. In this paper, we report the search results for such dark matter from PandaX-II experiment, using total data of the full 100.7 tonne$\cdot$day exposure. No significant excess is observed, so strong constraints on the combined parameter space of mediator mass and dark matter mass are derived. With the complementary search results from collider experiments, a large range of parameter space can be excluded.

    ↳ hep-exhep-phPLB(2022)·10 citations
26. 26*

    New Way to Resum the Lattice QCD Taylor Series Equation of State at Finite Chemical Potential

    Sabarnya Mitra🇮🇳 · Prasad Hegde🇮🇳 · Christian Schmidt🇩🇪

    Taylor expansion of the thermodynamic potential in powers of the (baryo)chemical potential ${\mu }_B$ is a well-known method to bypass the Sign Problem of Lattice QCD. Due to the difficulty in calculating the higher order Taylor coefficients, various alternative expansion schemes as well as resummation techniques have been suggested to extend the Taylor series to larger values of ${\mu }_B$. Recently, a way to resum the contribution of the first $N$ charge density correlation functions $D_1,\dots ,D_N$ to the Taylor series to all orders in ${\mu }_B$ was proposed in Phys. Rev. Lett. 128, 2, 022001 (2022). The resummation takes the form of an exponential factor. Since the correlation functions are calculated stochastically, the exponential factor contains a bias which can be significant for large $N$ and ${\mu }_B$. In this paper, we present a new method to calculate the QCD equation of state based on the well-known cumulant expansion from statistics. By truncating the expansion at a maximum order $M$, we end up with only finite products of the correlation functions which can be evaluated in an unbiased manner. Although our formalism is also applicable for ${\mu }_B\ne 0$, here we present it for the simpler case of a finite isospin chemical potential ${\mu }_I$ for which there is no Sign Problem. We present and compare results for the pressure and the isospin density obtained using Taylor expansion, exponential resummation and cumulant expansion, and provide evidence that the absence of bias in the latter actually improves the convergence.

    ↳ hep-lathep-phnucl-exnucl-thPRD(2022)·26 citations
27. 27*

    Anisotropic diffusion cannot explain TeV halo observations

    Pedro De La Torre Luque🇸🇪 · Ottavio Fornieri🇮🇹 · Tim Linden🇸🇪

    TeV halos are regions of enhanced photon emissivity surrounding pulsars. While multiple sources have been discovered, a self-consistent explanation of their radial profile and spherically-symmetric morphology remains elusive due to the difficulty in confining high-energy electrons and positrons within ~20 pc regions of the interstellar medium. One proposed solution utilizes anisotropic diffusion to confine the electron population within a "tube" that is auspiciously oriented along the line of sight. In this work, we show that while such models may explain a unique source such as Geminga, the phase space of such solutions is very small and they are unable to simultaneously explain the size and approximate radial symmetry of the TeV halo population.

    ↳ astro-ph.HEastro-ph.GAhep-phPRD(2022)·33 citations
28. 28*

    Novel features of attractors and transseries in non-conformal Bjorken flows

    Syo Kamata🇵🇱 · Jakub Jankowski🇵🇱 · Mauricio Martinez🇺🇸

    In this work we investigate the impact of conformal symmetry breaking on hydrodynamization of a far-from-equilibrium fluid. We find a new kind of transseries solutions for the non-conformal hydrodynamic equations of a longitudinal boost invariant expanding plasma. The new transseries solutions unveil a rich physical structure which arises due to the interplay of different physical scales. In the perfect fluid case the non-conformal speed of sound slows down the cooling of the temperature due to the emergence of logarithmic corrections that depends on the mass of the particle. These terms propagate into the perturbative and non-perturbative sectors of the transseries once viscous corrections are included. The logarithmic mass contributions increase the asymptotic value of the Knudsen number while decreasing the damping rate of the transient non-hydrodynamic modes and thus, yielding to an extremely slow hydrodynamization process where flow lines merge to their forward attractor at extremely late times. The early time free streaming expansion is modified and receives logarithmic mass corrections induced by the shear-bulk couplings. The global flow structure and numerical analyses carried out in our work demonstrate the existence of the early and late-time attractors for the shear viscous tensor and bulk viscous pressure.

    ↳ physics.flu-dyncond-mat.stat-mechhep-phhep-th+1PRD(2023)·16 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.