Tue·Sep 13, 2022Tuesday·September 13, 2022

1. 01*

   Gauge bosons masses in the context of the Supersymmetric $SU(3{)}_C\otimes SU(3{)}_L\otimes U(1{)}_N$ Model

   M. C. Rodriguez🇧🇷

   In this article, we present a detailed study of the masses of all gauge bosons, as well as explaing recent experimental data regarding the $W$-boson mass presented by the CDF collaboration and even possible changes that these data can bring to experimental measurements of the masses of $Z$-boson mass in the context of the Minimal Supersymmetric $SU(3{)}_C\otimes SU(3{)}_L\otimes U(1{)}_N$ Model. We also intend to show a phenomenological analysis of possible mixtures of gauge bosons in this model. We will show that our numerical predictions for the masses of the physical gauge bosons are within the current experimental limits.

   hep-phInt.J.Mod.Phys.A(2024)·6 citations
2. 02*

   Dark Sector Physics at High-Intensity Experiments

   Stefania Gori🇺🇸 · Mike Williams🇺🇸 · Phil Ilten🇺🇸 · Nhan Tran🇺🇸 · Gordan Krnjaic🇺🇸 · Natalia Toro🇺🇸 · Brian Batell🇺🇸 · Nikita Blinov🇨🇦 · Christopher Hearty🇨🇦 · Robert McGehee🇺🇸 · Philip Harris🇺🇸 · Philip Schuster🇺🇸 · Jure Zupan🇺🇸

   Is Dark Matter part of a Dark Sector? The possibility of a dark sector neutral under Standard Model (SM) forces furnishes an attractive explanation for the existence of Dark Matter (DM), and is a compelling new-physics direction to explore in its own right, with potential relevance to fundamental questions as varied as neutrino masses, the hierarchy problem, and the Universe's matter-antimatter asymmetry. Because dark sectors are generically weakly coupled to ordinary matter, and because they can naturally have MeV-to-GeV masses and respect the symmetries of the SM, they are only mildly constrained by high-energy collider data and precision atomic measurements. Yet upcoming and proposed intensity-frontier experiments will offer an unprecedented window into the physics of dark sectors, highlighted as a Priority Research Direction in the 2018 Dark Matter New Initiatives (DMNI) BRN report. Support for this program -- in the form of dark-sector analyses at multi-purpose experiments, realization of the intensity-frontier experiments receiving DMNI funds, an expansion of DMNI support to explore the full breadth of DM and visible final-state signatures (especially long-lived particles) called for in the BRN report, and support for a robust dark-sector theory effort -- will enable comprehensive exploration of low-mass thermal DM milestones, and greatly enhance the potential of intensity-frontier experiments to discover dark-sector particles decaying back to SM particles.

   hep-phastro-ph.COhep-exhep-th84 citations
3. 03*

   An economical model for $B$-flavour and $a_{\mu }$ anomalies from SO(10) grand unification

   Ufuk Aydemir🇹🇷 · Tanumoy Mandal🇮🇳 · Subhadip Mitra🇮🇳 · Shoaib Munir🇷🇼

   We investigate an $\mathrm{SO}(10)$ grand unification scenario where the complex 10-dimensional scalar multiplet, containing the Standard Model (SM) Higgs boson, resides at the TeV scale altogether. The resulting low-energy model is a 2-Higgs-doublet model augmented with two $S_1$-type leptoquarks. The gauge-coupling unification is achieved with only one intermediate scale at which the Pati-Salam gauge group is broken down to the SM. Proton stability is ensured by a discrete symmetry, leftover from the breaking of the U(1)${}_{\mathrm{PQ}}$ global symmetry. The axion corresponding to this broken U(1)${}_{\mathrm{PQ}}$ provides a solution to the strong CP problem, and also serves as an important dark matter candidate. We discuss how the simultaneous explanation for the $R_{D^{(\ast )}}$ and $a_{\mu }$ anomalies comes about in the model, and investigate some of its phenomenological implications.

   hep-ph12 citations
4. 04*

   Singlet vector leptoquark model facing recent LHCb and BABAR measurements

   Cristian H. García-Duque🇨🇴 · J. M. Cabarcas🇨🇴 · J. H. Muñoz🇨🇴 · Néstor Quintero🇨🇴 · Eduardo Rojas🇨🇴

   Very recently the LHCb experiment released the first measurement of the ratio $R({\Lambda }_c)=\mathrm{BR}({\Lambda }_b\to {\Lambda }_c\tau {\bar{\nu }}_{\tau })/\mathrm{BR}({\Lambda }_b\to {\Lambda }_c\mu {\bar{\nu }}_{\mu })$. Moreover, the BABAR experiment reported a new result of the leptonic decay ratio of Upsilon meson ${\rm Y}(3S)$, namely, $R_{{\rm Y}(3S)}=\mathrm{BR}({\rm Y}(3S)\to {\tau }^{+}{\tau }^{-})/\mathrm{BR}({\rm Y}(3S)\to {\mu }^{+}{\mu }^{-})$. Both measurements are below their corresponding Standard Model predictions (deficit), deviating by $\sim 1.1\sigma$ and $\sim 1.8\sigma$, respectively. Moreover, the LHCb recently presented the first search of the lepton flavor violating decay $B^0\to K^{\ast 0}{\mu }^{\pm }{\tau }^{\mp }$. Motivated by these new data, in this work we study their impact on the phenomenology of the singlet vector leptoquark ($U_1$) model addressing the hints of lepton flavor universality violation in the semileptonic decays of $B$ mesons ($B$ meson anomalies), by carrying out a global fit analysis. In general, we found that a minimal version of the $U_1$ model with a mass of 1.8 TeV can successfully explain the $B$ meson anomalies, while being compatible with all other flavor observables and LHC bounds. Interestingly, our study shows that the new observables $R({\Lambda }_c)$ and $R_{{\rm Y}(3S)}$ generate strong tension, leading to non-trivial effects on the global fit. Future improvements at the LHCb and Belle II experiments would help to understand their complementarity. Moreover, we also analyze the impact of the expected sensitivity on flavor observables at Belle II to provide a further test of the $U_1$ model. Finally, we study the minimal assumptions under which the $U_1$ model could, in addition, provide a combined explanation of the anomalous magnetic moment of the muon.

   hep-phNPB(2023)·7 citations
5. 05*

   Asymmetric Dark Matter from Gravitational Waves

   Bartosz Fornal🇺🇸 · Erika Pierre🇺🇸

   We investigate the prospects for probing asymmetric dark matter models through their gravitational wave signatures. We concentrate on a theory extending the Standard Model gauge symmetry by a non-Abelian group, under which leptons form doublets with new fermionic partners, one of them being a dark matter candidate. The breaking of this new symmetry occurs at a high scale, and results in a strong first order phase transition in the early Universe. The model accommodates baryogenesis in an asymmetric dark matter setting and predicts a gravitational wave signal within the reach of near-future experiments.

   hep-phPRD(2022)·11 citations
6. 06*

   Exploring and exploiting various regimes within the jet shower

   Raghav Kunnawalkam Elayavalli🇺🇸

   The last few years have seen community-wide excitement in the study of jet substructure derived from the inner workings of clustering algorithms. Such efforts have resulted in the design of new observables which are related to partonic processes from final state hadrons. Since jets are multi-scale objects, they necessarily encode information about both the perturbative (pQCD) parton shower and non-perturbative (npQCD) physics including hadronization. Recent high precision measurements of jet substructure in proton-proton (pp) collisions have pushed the theoretical community into extending their predictions to higher orders resulting in the observation of large theoretical uncertainties from the non-perturbative regime of the calculations. We emphasize the importance of understanding a jet shower from a multi-dimensional point of view and highlight a recent measurement focused on distinguishing the pQCD vs. npQCD regimes within a jet shower. We introduce and discuss the utility of the formation time evaluated at varying stages of the jet shower in pp collisions. Finally, we present a monte-carlo study of the formation time of charged particles within the jet to gain a handle on hadronization mechanisms including string-breaking, and outline a path forward for such observables in heavy ion collisions.

   hep-phhep-exRev.Mex.Fis.Suppl.(2022)·2 citations
7. 07*

   The effective potential of the Polyakov loop in the Hamiltonian approach to QCD

   Markus Quandt🇩🇪 · Hugo Reinhardt🇩🇪

   We investigate the effective potential of the Polyakov loop, which is the order parameter for the deconfinement phase transition in finite temperature QCD. Our work is based on the Hamiltonian approach in Coulomb gauge where finite temperature $T$ is introduced by compactifying one space direction. We briefly review this approach and extend earlier work in the Yang-Mills sector by including dynamical quarks. In a first approximation, we follow the usual functional approach and include only one-loop contributions to the energy, with the finite temperature propagators replaced by their $T=0$ counter parts. It is found that this gives a poor description of the phase transition, in particular for the case of full QCD with $N_f=3$ light flavours. The physical reasons for this unexpected result are discussed, and pinned down to a relative weakness of gluon confinement compared to the deconfining tendency of the quarks. We attempt to overcome this issue by including the relevant gluon contributions from the two-loop terms to the energy. We find that the two-loop corrections have indeed a tendency to strengthen the gluon confinement and weaken the unphysical effects in the confining phase, while slightly increasing the (pseudo-)critical temperature $T^{\ast }$ at the same time. To fully suppress artifacts in the confining phase, we must tune the parameters to rather large values, increasing the critical temperature to $T^{\ast }\approx 340\mathrm{MeV}$ for $G=SU(2)$.

   hep-phhep-lathep-thPRD(2022)·1 citation
8. 08*

   Evolution of charm-meson ratios in an expanding hadron gas

   Eric Braaten🇺🇸 · Roberto Bruschini🇪🇸 · Li-Ping He🇩🇪 · Kevin Ingles🇺🇸 · Jun Jiang🇨🇳

   We study the time evolution of the numbers of charm mesons after the kinetic freeze-out of the hadron gas produced by a central heavy-ion collision. The $\pi D^{\ast }\to \pi D^{\ast }$ reaction rates have $t$-channel singularities that give contributions inversely proportional to the thermal width of the $D$. The ratio of the $D^0$ and $D^{+}$ production rates can differ significantly from those predicted using the measured $D^{\ast }$ branching fractions.

   hep-phPRD(2023)·4 citations
9. 09*

   Exploration of trace anomaly contribution to proton mass based on light vector meson photoproduction

   Chen Dong🇨🇳 · Jiyuan Zhang🇨🇳 · Jingxuan Bu🇨🇳 · Huifang Zhou🇨🇳 · Xiao-Yun Wang🇨🇳

   In the quantum chromodynamics, the mass source of the proton is decomposed into four parts by the energy momentum tensor : quark energy term, gluon energy term, quark mass term and trace anomaly term. And the trace anomaly term is the most crucial contribution for studying the internal structure of the proton. In this work, under the definition of the vector meson dominant model, the trace anomaly contribution of the proton is extracted from the experimental datas of light vector mesons $\rho$, $\omega$ and $\varphi$ photoproduction at the near-threshold, which are ($1.15\pm 0.08$)$\%$, ($2.70\pm 0.04$)$\%$ and ($5.58\pm 0.25$)$\%$, respectively. Eventually, the average trace anomaly contribution of the proton is ($4.36\pm 0.40$) $\%$, which only account for a small fraction of the total proton mass. The result of this work will provide theoretical information support for further study of proton internal structure.

   hep-phnucl-thEPJC(2023)·4 citations
10. 10*

    Unitarity and Dilaton effective theory

    Deog Ki Hong🇰🇷 · Gyurin Kim🇰🇷 · Jun Beom Park🇰🇷

    From the low-energy effective theory of dilatons, consistent with the scale anomaly, we calculate the $2\to 2$ scattering amplitudes of dilatons. We find that the one-loop amplitude violates the unitarity bound as the scattering energy approaches the cutoff of the effective theory, $\sqrt{s}=\sqrt{4\pi }{f}_D$. We then show that the inclusion of the next-to-lightest state, namely the spin-2 state, of mass around the cutoff improves the unitarity. The unitarity argument suggests that the mass ratio of the dilaton and the spin-2 state is proportional to the square of the Miransky-BKT scaling of the near conformal dynamics.

    hep-phhep-thJ.Korean Phys.Soc.(2022)·0 citations
11. 11*

    Machine-enhanced CP-asymmetries in the electroweak sector

    Noah Clarke Hall🇬🇧 · Isaac Criddle🇬🇧 · Archie Crossland🇬🇧 · Christoph Englert🇬🇧 · Patrick Forbes🇬🇧 · Robert Hankache🇬🇧 · Andrew D. Pilkington🇬🇧

    The violation of charge conjugation (C) and parity (P) symmetries are a requirement for the observed dominance of matter over antimatter in the Universe. As an established effect of beyond the Standard Model physics, this could point towards additional CP violation in the Higgs-gauge sector. The phenomenological footprint of the associated anomalous couplings can be small, and designing measurement strategies with the highest sensitivity is therefore of the utmost importance in order to maximise the discovery potential of the Large Hadron Collider (LHC). There are, however, very few measurements of CP-sensitive observables in processes that probe the weak-boson self-interactions. In this article, we study the sensitivity to new sources of CP violation for a range of experimentally-accessible electroweak processes, including $W\gamma$ production, $WW$ production via photon fusion, electroweak $Zjj$ production, electroweak $ZZjj$ production, and electroweak $W^{\pm }{W}^{\pm }jj$ production. We study simple angular observables as well CP-sensitive observables constructed using the outputs of machine-learning (ML) algorithms. We find that the ML-constructed CP-sensitive observables improve the sensitivity to CP-violating effects by up to a factor of five, depending on the process. We also find that inclusive $W\gamma$ and electroweak $Zjj$ production have the potential to set the best possible constraints on certain CP-odd operators in the Higgs-gauge sector of dimension-six effective field theories.

    hep-phhep-exPRD(2023)·16 citations
12. 12*

    Charmoniumlike resonant explanation on the newly observed $X(3960)$

    Rui Chen🇨🇳 · Qi Huang🇨🇳

    Stimulated by the observation of the newly $X(3960)$ observed by the LHCb collaboration, we adopt the one-boson-exchange model and consider the $S-D$ wave mixing effects to study the $D_s{\bar{D}}_s/D^{\ast }{\bar{D}}^{\ast }/D_s^{\ast }{\bar{D}}_s^{\ast }$ interactions with $I(J^{PC})=0(0^{++})$. After producing the phase shifts of this coupled channel systems, our results show that there can exist a charmoniumlike resonance, whose obtained mass and width can both well match with the experimental data of the newly observed $X(3960)$. We also find that the $D^{\ast }{\bar{D}}^{\ast }$ system plays an important role in the formation of the newly observed $X(3960)$ as a charmoniumlike resonance, and the $D_s^{\ast }{\bar{D}}_s^{\ast }$ system makes a significant contribution to the resonant width. As a byproduct, we perform a coupled channel analysis on the $D^{\ast }{\bar{D}}^{\ast }/D_s{\bar{D}}_s^{\ast }/D_s^{\ast }{\bar{D}}_s^{\ast }$ interactions with $I(J^{PC})=0(1^{+-})$, our results can predict the existence of the $D_s{\bar{D}}_s^{\ast }$ molecule with $1^{+-}$ and the $D_s^{\ast }{\bar{D}}_s^{\ast }$ molecule with $1^{+-}$. Their widths are around several and several to several tens MeV, respectively. Experimental searches for these two possible charmoniumlike molecular candidates can be helpful to verify our proposal.

    hep-phPLB(2023)·18 citations
13. 13*

    FCNC $B$ and $K$ Meson Decays with Light Bosonic Dark Matter

    Xiao-Gang He🇨🇳 · Xiao-Dong Ma🇨🇳 · German Valencia🇦🇺

    We consider decays of $B$ and $K$ mesons into a pseudo-scalar or vector meson plus missing energy. Within the SM, these modes originate from flavor changing neutral current (FCNC) processes with two neutrinos in the final state. In this paper we consider the experimental upper bounds on these modes and interpret the difference between these bounds and the SM prediction as a window into new light invisible particles. In particular we consider the case where some new symmetry requires the new particles to be produced in pairs. We first construct the general low energy effective Lagrangian coupling an FCNC with two dark sector particles of spin zero, one-half and one. We then present numerical estimates for the constraints that can be placed on these interactions, finding that an effective new physics scale from $\mathcal{O}(10)$-$\mathcal{O}(10^{11})$ GeV can be probed, with the exact value strongly depending on the interaction structure as well as the mass of the invisible particle. For $K^{+}\to {\pi }^{+}/E$ we incorporate into our constraints the effect of using only the signal regions of NA62, and for $B^{+}\to K^{+}/E$ the $q^2$-dependent efficiency of Belle II.

    hep-phhep-exJHEP(2023)·42 citations
14. 14*

    Imprints of scalar NSI on the CP-violation sensitivity using synergy among DUNE, T2HK and T2HKK

    Abinash Medhi🇮🇳 · Moon Moon Devi🇮🇳 · Debajyoti Dutta🇮🇳

    The Non-Standard Interactions (NSIs) are subdominant effects, often appearing in various extensions of SM, which may impact the neutrino oscillations through matter. It is important and interesting to explore the impact of NSIs in the ongoing and upcoming precise neutrino oscillations experiments. In this work, we have studied the imprints of a scalar-mediated NSI in three upcoming long-baseline (LBL) experiments (DUNE, T2HK, T2HKK). The effects of scalar NSI appears as a medium-dependent correction to the neutrino mass term. Its contribution scales linearly with matter density, making LBL experiments a suitable candidate to probe its effects. We show that the scalar NSI may significantly impact the oscillation probabilities, event rates at the detectors and the ${\chi }^2$-sensitivities of ${\delta }_{CP}$ measurements. We present the results of a combined analysis involving the LBL experiments (DUNE+T2HK, DUNE+T2HKK, DUNE+T2HK+T2HKK) which offer a better capability of constraining the scalar NSI parameters as well as an improved sensitivity towards CP-violation.

    hep-phhep-exJHEP(2023)·23 citations
15. 15*

    Semileptonic weak Hamiltonian to $\mathcal{O}(\alpha {\alpha }_s({\mu }_{\mathrm{Lattice}}))$ in momentum-space subtraction schemes

    M. Gorbahn🇬🇧 · S. Jäger🇬🇧 · F. Moretti🇬🇧 · E. van der Merwe🇬🇧

    The CKM unitarity precision test of the Standard Model requires a systematic treatment of electromagnetic and strong corrections for semi-leptonic decays. Electromagnetic corrections require the renormalization of a semileptonic four-fermion operator. In this work we calculate the $\mathcal{O}(\alpha {\alpha }_s)$ perturbative scheme conversion between the $\overline{\mathrm{MS}}$ scheme and several momentum-space subtraction schemes, which can also be implemented on the lattice. We consider schemes defined by MOM and SMOM kinematics and emphasize the importance of the choice of projector for each scheme. The conventional projector, that has been used in the literature for MOM kinematics, generates QCD corrections to the conversion factor that do not vanish for $\alpha =0$ and which generate an artificial dependence on the lattice matching scale that would only disappear after summing all orders of perturbation theory. This can be traced to the violation of a Ward identity that holds in tha $\alpha =0$ limit. We show how to remedy this by judicious choices of projector, and prove that the Wilson coefficients in those schemes are free from pure QCD contributions. The resulting Wilson coefficients (and operator matrix elements) have greatly reduced scale dependence. Our choice of the $\overline{\mathrm{MS}}$ scheme over the traditional $W$-mass scheme is motivated by the fact that, besides being more tractable at higher orders, unlike the latter it allows for a transparent separation of scales. We exploit this to obtain renormalization-group-improved leading-log and next-to-leading-log strong corrections to the electromagnetic contributions and study the (QED-induced) dependence on the lattice matching scale.

    hep-phhep-latJHEP(2023)·15 citations
16. 16*

    Accessing GPDs through the exclusive photoproduction of a $\gamma$-meson pair

    Goran Duplančić🇭🇷 · Saad Nabeebaccus🇫🇷 · Kornelija Passek-Kumerički🇭🇷 · Bernard Pire🇫🇷 · Lech Szymanowski🇵🇱 · Samuel Wallon🇫🇷

    We consider the exclusive photo-production of a photon-meson pair with a large invariant mass, working in the QCD factorisation framework. Explicitly, we consider a $\rho$-meson or a charged $\pi$ in the final state. This process gives access both to chiral-even GPDs and chiral-odd GPDs, which are not well-known experimentally, especially the latter ones. The computation is performed at leading order and leading twist. We discuss the prospects of measuring them in experiments, focusing on the kinematics at the JLab 12-GeV experiment, and pPb ultra-peripheral collisions at LHC. In particular, the latter gives access to the small $\xi$ regime of GPDs.

    hep-phhep-exnucl-exnucl-th2 citations
17. 17*

    Gluon Transverse-Momentum-Dependent Distributions from Large-Momentum Effective Theory

    Ruilin Zhu🇨🇳 · Yao Ji🇩🇪 · Jian-Hui Zhang🇨🇳 · Shuai Zhao🇺🇸

    We demonstrate that gluon transverse-momentum-dependent parton distribution functions (TMDPDFs) can be extracted from lattice calculations of appropriate Euclidean correlations in large-momentum effective theory (LaMET). Based on perturbative calculations of gluon unpolarized and helicity TMDPDFs, we present a matching formula connecting them and their LaMET counterparts, where the latter are renormalized in a scheme facilitating lattice calculations and converted to the $\overline{\mathrm{MS}}$ scheme. The hard matching kernel is given up to one-loop level. We also show that the perturbative result is independent of the prescription used for the pinch-pole singularity in the relevant correlations. Our results offer a guidance for the extraction of gluon TMDPDFs from lattice simulations, and have the potential to greatly facilitate perturbative calculations of the hard matching kernel.

    hep-phhep-latnucl-thJHEP(2023)·26 citations
18. 18*

    Black holes don't source fast Higgs vacuum decay

    Alessandro Strumia🇮🇹

    We argue that the rate of Standard Model vacuum or thermal decay seeded by primordial black holes is negligible (because non-perturbatively suppressed by the small quartic Higgs coupling) and independent of the non-minimal coupling of the Higgs to gravity.

    hep-phhep-thJHEP(2023)·31 citations
19. 19*

    Structure Formation and the Global 21-cm Signal in the Presence of Coulomb-like Dark Matter-Baryon Interactions

    Trey Driskell🇺🇸 · Ethan O. Nadler🇺🇸 · Jordan Mirocha🇨🇦 · Andrew Benson🇺🇸 · Kimberly K. Boddy🇺🇸 · Timothy D. Morton🇺🇸 · Jack Lashner🇺🇸 · Rui An🇺🇸 · Vera Gluscevic🇺🇸

    Many compelling dark matter (DM) scenarios feature Coulomb-like interactions between DM particles and baryons, in which the cross section for elastic scattering scales with relative particle velocity as $v^{-4}$. Previous studies have invoked such interactions to produce heat exchange between cold DM and baryons and alter the temperature evolution of hydrogen. In this study, we present a comprehensive study of the effects of Coulomb-like scattering on structure formation, in addition to the known effects on the thermal history of hydrogen. We find that interactions which significantly alter the temperature of hydrogen at Cosmic Dawn also dramatically suppress the formation of galaxies that source the Lyman-$\alpha$ background, further affecting the global 21-cm signal. In particular, an interaction cross section at the current observational upper limit leads to a decrease in the abundance of star-forming halos by a factor of $\sim 2$ at $z\sim 20$, relative to cold, collisionless DM. We also find that DM that is 100% millicharged cannot reproduce the depth and the timing of the reported EDGES anomaly in any part of the parameter space. These results critically inform modeling of the global 21-cm signal and structure formation in cosmologies with DM-baryon scattering, with repercussions for future and upcoming cosmological data analysis.

    ↳ astro-ph.COhep-phPRD(2022)·30 citations
20. 20*

    Universal horizons and black hole spectroscopy in gravitational theories with broken Lorentz symmetry

    Chao Zhang🇨🇳 · Anzhong Wang🇺🇸 · Tao Zhu🇨🇳

    The violation of Lorentz invariance (LI) in gravitational theories, which allows superluminal propagations, dramatically alters the causal structure of the spacetime and modifies the notion of black holes (BHs). Instead of metric horizons, now universal horizons (UHs) define the boundaries of BHs, within which a particle cannot escape to spatial infinities even with an infinitely large speed. Then, a natural question is how the quasi-normal modes (QNMs) of a BH are modified, if one considers the UH as its causal boundary. In this paper, we study in detail this problem in Einstein-aether theory, a vector-tensor theory that violates LI but yet is self-consistent and satisfies all observations to date. Technically, this poses several challenges, including singularities of the perturbation equations across metric horizons and proper identifications of ingoing modes at UHs. After overcoming these difficulties, we show that the QNMs of the Schwarzschild BH, also a solution of Einstein-aether theory, consist of two parts, the metric and aether parts. The QNMs of the metric perturbations are quite similar to those obtained in general relativity and are consistent with current observations of gravitational waves. But the ones from aether perturbations are different, and our numerical studies indicate that they are even not stable. The latter is consistent with our previous studies, which showed that the stealth Schwarzschild BH suffers a Laplacian instability along the angular direction. The method and techniques developed in this paper can be applied to the studies of QNMs in other theories of gravity with broken LI.

    ↳ gr-qchep-phhep-thmath-ph+1EPJC(2023)·7 citations
21. 21*

    Global and local polarization of $\Lambda$ ($\bar{\Lambda }$) hyperons in Pb--Pb collisions in ALICE at the LHC

    Debojit Sarkar🇺🇸

    The global polarization of the $\Lambda$ and $\bar{\Lambda }$ hyperons ($P_{\mathrm{H}}$) has been measured in Pb--Pb collisions at $\text{sNN}=$ 2.76 TeV and 5.02 TeV in ALICE at the Large Hadron Collider (LHC). The hyperon global polarization is found to be consistent with zero at both collision energies. The local polarization of the $\Lambda$ and $\bar{\Lambda }$ hyperons along the beam ($z$) direction, $P_{\mathrm{z}}$, has also been measured in Pb--Pb collisions at $\text{sNN}=5.02$ TeV. The $P_{\mathrm{z}}$, measured as a function of the hyperon emission angle relative to the second harmonic symmetry plane, exhibits a second harmonic sine modulation, as expected due to elliptic flow. The measurements of global and local hyperon polarization are reported for different collision centralities and as a function of transverse momentum in semicentral collisions. These results show the first experimental evidence of a non-zero hyperon $P_{\mathrm{z}}$ in Pb--Pb collisions at the LHC.

    ↳ hep-exhep-phnucl-exphysics.data-anEPJ Web Conf.(2022)·2 citations
22. 22*

    Holographic Non-local Rotating Observables and their Renormalization

    Vangelis Giantsos🇬🇷 · Dimitrios Giataganas🇹🇼

    We analyse non-local rotating observables in holography corresponding to spinning bound states. To renormalize their energies and momenta we suggest and discuss different holographic renormalization schemes motivated by the static non-local observables. Namely the holographic renormalization and the rotating color singlet mass subtraction scheme. In the holographic renormalization we identify the infinite boundary terms and subtract them. In the mass subtraction scheme we evaluate the energy of a spinning trailing string corresponding to the color charged singlet which experiences dragging phenomena and we subtract it from the energy of the bound state to obtain the renormalized finite energy. Then we apply our generic framework to certain strongly coupled thermal theories with broken rotational symmetry. We find numerical solutions corresponding to spinning bound states with a fixed size while varying their angular frequency. By applying numerically the renormalization schemes, we find that there is a critical frequency where the bound state ceases to exist or dissociates. We also note that bound states require lower angular frequencies to dissociate when the theory has less symmetry.

    ↳ hep-thhep-phPRD(2022)·6 citations
23. 23*

    Gravitational waves from rapid structure formation on microscopic scales before matter-radiation equality

    Marcos M. Flores🇺🇸 · Alexander Kusenko🇺🇸 · Misao Sasaki🇯🇵

    The existence of scalar fields can be probed by observations of stochastic gravitational waves. Scalar fields mediate attractive forces, usually stronger than gravity, on the length scales shorter than their Compton wavelengths, which can be non-negligible in the early Universe, when the horizon size is small. These attractive forces exhibit an instability similar to the gravitational instability, only stronger. They can, therefore, lead to the growth of structures in some species. We identify a gravitational waves signature of such processes and show that it can be detected by future gravitational waves experiments.

    ↳ astro-ph.COgr-qchep-phPRL(2023)·16 citations
24. 24*

    Geometry of Spin(10) Symmetry Breaking

    Kirill Krasnov🇬🇧

    We provide a new characterisation of the Standard Model gauge group GSM as a subgroup of Spin(10). The new description of GSM relies on the geometry of pure spinors. We show that GSM is the subgroup that stabilises a pure spinor Psi_1 and projectively stabilises another pure spinor Psi_2, with Psi_1, Psi_2 orthogonal and such that their arbitrary linear combination is still a pure spinor. Our characterisation of GSM relies on the facts that projective pure spinors describe complex structures on R^{10}, and the product of two commuting complex structures is a what is known as a product structure. For the pure spinors Psi_1, Psi_2 satisfying the stated conditions the complex structures determined by Psi_1, Psi_2 commute and the arising product structure is R^{10} = R^6 + R^4, giving rise to a copy of Pati-Salam gauge group inside Spin(10). Our main statement then follows from the fact that GSM is the intersection of the Georgi-Glashow SU(5) that stabilises Psi_1, and the Pati-Salam Spin(6) x Spin(4) arising from the product structure determined by Psi_1, Psi_2. We have tried to make the paper self-contained and provided a detailed description of the creation/annihilation operator construction of the Clifford algebras Cl(2n) and the geometry of pure spinors in dimensions up to and including ten.

    ↳ hep-thhep-phmath.DGJ.Math.Phys.(2024)·9 citations
25. 25*

    Empirical determination of the Bohr-Weisskopf effect in cesium and improved tests of precision atomic theory in searches for new physics

    G. Sanamyan🇦🇺 · B. M. Roberts🇦🇺 · J. S. M. Ginges🇦🇺

    The finite distribution of the nuclear magnetic moment across the nucleus gives a contribution to the hyperfine structure known as the Bohr-Weisskopf (BW) effect. We have obtained an empirical value of -0.24(18)% for this effect in the ground and excited s states of atomic Cs-133. This value is found from historical muonic-atom measurements in combination with our muonic-atom and atomic many-body calculations. The effect differs by 0.5% in the hyperfine structure from the value found using the uniform magnetization distribution, which has been commonly employed in the precision heavy-atom community over the last several decades. We also deduce accurate values for the BW effect in other isotopes and states of cesium. These results enable cesium atomic wave functions to be tested in the nuclear region at an unprecedented 0.2% level, and are needed for the development of precision atomic many-body methods. This is important for increasing the discovery potential of precision atomic searches for new physics, in particular for atomic parity violation in cesium.

    ↳ physics.atom-phhep-phnucl-exnucl-thPRL(2023)·17 citations
26. 26*

    Constraints on the positron emission from pulsar populations with AMS-02 data

    Silvia Manconi🇩🇪

    Electron and positron fluxes in cosmic rays are currently measured with unprecedented precision by AMS-02 up to TeV energies, and represent unique probes for the local properties of our Galaxy. The interpretation of their spectra is at present still debated, especially for the excess of positrons above 10 GeV. The hypothesis that pulsars can significantly contribute to this excess has been consolidated after the observation of gamma-ray halos at TeV energies of a few degree size around Geminga and Monogem pulsars. However, the spatial and energetic Galactic distribution of pulsars and the details of the positron production, acceleration and release from these sources are not yet fully understood. I will describe how we can use the high-precision AMS-02 positron data to constrain the main properties of the Galactic pulsar population and of the positron acceleration needed to explain the observed fluxes. This is achieved by simulating a large number of Galactic pulsar populations, following the most recent self-consistent modelings for the pulsar spin-down and evolution properties, calibrated on catalog observations. By fitting the positron AMS-02 data together with a secondary component due to collisions of primary cosmic rays with the interstellar medium, we determine the physical parameters of the pulsars dominating the positron flux, and assess the impact of different assumptions on radial distributions, spin-down properties, Galactic propagation scenarios and positron emission time.

    ↳ astro-ph.HEhep-ph0 citations
27. 27*

    Squeezed spectra and elliptic flow of bosons and anti-bosons with in-medium mass splitting

    Yong Zhang🇨🇳 · Shi-Yao Wang🇨🇳 · Peng Ru🇨🇳 · Wei-Hua Wu🇨🇳

    We study the impact of the in-medium mass splitting between bosons and anti-bosons on their spectra and elliptic flow. The in-medium mass splitting may cause a separation in the transverse momentum spectra, as well as a division in the elliptic flow between bosons and anti-bosons. The magnitude of this effect becomes greater as the in-medium mass splitting increases. With the increasing rapidity, the splitting effect of the spectra increases and the splitting effect of the elliptic flow decreases. These phenomena may provide a way to differentiate whether the influences on boson and anti-boson in the medium are consistent.

    ↳ nucl-thhep-phIJMPE(2023)·0 citations
28. 28*

    Enhanced dilepton emission from a phase transition in dense matter

    O. Savchuk🇺🇦 · A. Motornenko🇩🇪 · J. Steinheimer🇩🇪 · V. Vovchenko🇺🇸 · M. Bleicher🇩🇪 · M. Gorenstein🇺🇦 · T. Galatyuk🇩🇪

    It is demonstrated that the presence of a phase transition in heavy ion collisions, at beam energies that probe dense QCD matter, leads to a significant enhancement of the dilepton yield per produced pion due to the extended emission time. In addition, the temperature of low mass dileptons shows a modest decrease due to the mixed phase. The emission of dileptons in the SIS18-SIS100 beam energies range is studied by augmenting the UrQMD transport model with a realistic density dependent equation of state, as well as two different phase transitions. This is achieved by extending the molecular dynamics interaction part of the UrQMD model to a density dependent interaction potential with a high density minimum leading to a phase transition and metastable coexisting high density states. Together with a high precision measurement these simulations will be able to constrain the existence of a phase transition in QCD up to densities of several times nuclear saturation density.

    ↳ nucl-thhep-exhep-phnucl-exJ.Phys.G(2023)·29 citations
29. 29*

    Yangian-invariant fishnet integrals in 2 dimensions as volumes of Calabi-Yau varieties

    Claude Duhr🇩🇪 · Albrecht Klemm🇩🇪 · Florian Loebbert🇩🇪 · Christoph Nega🇩🇪 · Franziska Porkert🇩🇪

    We argue that $\ell$-loop Yangian-invariant fishnet integrals in 2 dimensions are connected to a family of Calabi-Yau $\ell$-folds. The value of the integral can be computed from the periods of the Calabi-Yau, while the Yangian generators provide its Picard-Fuchs differential ideal. Using mirror symmetry, we can identify the value of the integral as the quantum volume of the mirror Calabi-Yau. We find that, similar to what happens in string theory, for $\ell =1$ and 2 the value of the integral agrees with the classical volume of the mirror, but starting from $\ell =3$, the classical volume gets corrected by instanton contributions. We illustrate these claims on several examples, and we use them to provide for the first time results for 2- and 3-loop Yangian-invariant traintrack integrals in 2 dimensions for arbitrary external kinematics.

    ↳ hep-thhep-phmath-phmath.MPPRL(2023)·71 citations
30. 30*

    Snowmass Neutrino Frontier: NF02 Topical Group Report on Understanding Experimental Neutrino Anomalies

    Georgia Karagiorgi🇺🇸 · Bryce R. Littlejohn🇺🇸 · Pedro Machado🇺🇸 · Alexandre Sousa (on behalf of the NF02 Topical Group Community)🇺🇸

    This report has been prepared as part of the US Community Study on the Future of Particle Physics (Snowmass 2021) by the Snowmass Neutrino Frontier Topical Group NF02 Conveners, and it is based on the NF02 Topical Group-contributed White Paper on Light Sterile Neutrino Searches and Related Phenomenology.

    ↳ hep-exhep-ph6 citations
31. 31*

    Electromagnetic Structure of Spin-$\frac{1}{2}$ Doubly Charmed Baryons in Lattice QCD

    H. Bahtiyar🇹🇷

    We compute the electromagnetic properties of spin-$\frac{1}{2}$ doubly charmed baryons on 2+1 flavor lattices that have a pion mass of $\sim$ 156 MeV. The Tsukuba action is employed for the charm quark in addition to the standard isotropic Clover action to quantify the $\mathcal{O}(m_{q}a)$ effects. We calculate the electric and magnetic Sachs form factors and extract the magnetic moments and electric and magnetic charge radii. We also investigate the individual quark sector contributions to the charge radii and the magnetic moments. The results provide vital information to understand the size and shape of the doubly charmed baryons. We find that the two heavy charm quarks drive the charge radii and the magnetic moments to smaller values than that of light baryons. The central values of the observables that are obtained using the relativistic action for the charm quark are $5$ to $10\%$ larger than those obtained using the Clover action. Utilizing the available lattice data, we reexamine the quark mass dependence of the observables.

    ↳ hep-lathep-phPRD(2023)·6 citations
32. 32*

    Generalized Parton Distributions from Lattice QCD with Asymmetric Momentum Transfer: Unpolarized Quarks

    Shohini Bhattacharya🇺🇸 · Krzysztof Cichy🇵🇱 · Martha Constantinou🇺🇸 · Jack Dodson🇺🇸 · Xiang Gao🇺🇸 · Andreas Metz🇺🇸 · Swagato Mukherjee🇺🇸 · Aurora Scapellato🇺🇸 · Fernanda Steffens🇩🇪 · Yong Zhao🇺🇸

    Traditionally, lattice QCD computations of generalized parton distributions (GPDs) have been carried out in a symmetric frame, where the transferred momentum is symmetrically distributed between the incoming and outgoing hadrons. However, such frames are inconvenient since they require a separate calculation for each value of the momentum transfer, increasing significantly the computational cost. In this work, by focusing on the quasi-distribution approach, we lay the foundation for faster and more effective lattice QCD calculations of GPDs exploiting asymmetric frames, with freedom in the transferred momentum distribution. An important ingredient of our approach is the Lorentz covariant parameterization of the matrix elements in terms of Lorentz-invariant amplitudes, which allows one to relate matrix elements in different frames. We also use this amplitude approach to propose a new definition of quasi-GPDs that is frame-independent and, more importantly, may lead to smaller power corrections in the matching relations to the light-cone GPDs. We demonstrate the efficacy of the formalism through numerical calculations using one ensemble of $N_f$=2+1+1 twisted mass fermions with a clover improvement. The value of the light-quark masses lead to a pion mass of about 260 MeV. Concentrating on the proton, and limiting ourselves to a vanishing longitudinal momentum transfer to the target, we extract the invariant amplitudes from matrix element calculations in both the symmetric and asymmetric frame, and obtain results for the twist-2 light-cone GPDs for unpolarized quarks, that is, $H$ and $E$.

    ↳ hep-lathep-phPRD(2022)·93 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.