Tue·Sep 19, 2023Tuesday·September 19, 2023

1. 01*

   Constraining the low-energy S=-2 meson-baryon interaction with two-particle correlations

   V. Mantovani Sarti🇩🇪 · A. Feijoo🇪🇸 · I. Vidaña🇮🇹 · A. Ramos🇪🇸 · F. Giacosa🇵🇱 · T. Hyodo🇯🇵 · Y. Kamiya🇩🇪

   The two-particle correlation technique applied to $K^{-}\Lambda$ pairs in pp collisions at LHC recently provided the most precise data on the strangeness $S=-2$ meson-baryon interaction. In this letter, we use for the first time femtoscopic data to constrain the parameters of a low-energy effective QCD Lagrangian. The tuned model delivers new insights on the molecular nature of the $\Xi (1620)$ and $\Xi (1690)$ states. This procedure opens the possibility to determine higher order corrections, directly constraining QCD effective models particularly in the multi-strange and charm sectors.

   hep-phnucl-thPRD(2024)·41 citations
2. 02*

   Renormalization Group Improvement and QCD Sum Rules

   M. S. A. Alam Khan🇮🇳

   We summarize the results obtained for the quark masses (u,d,s,c, and b) in Refs.~\cite{AlamKhan:2023ili,AlamKhan:2023kgs} and strong coupling (${\alpha }_s$) using renormalization group (RG) improvement of the theoretical expressions and experimental inputs that enter in the QCD sum rules. We obtain $m_u(2GeV)=2.00_{-0.40}^{+0.33}$ MeV, $m_d(2GeV)=4.21_{-0.45}^{+0.48}$ MeV, and $m_s(2GeV)=104.34_{-4.24}^{+4.32}$ MeV using Borel Laplace sum rules for the divergence of the axial vector currents. The relativistic sum rules for the moments of the heavy quark currents lead to the determination of ${\alpha }_s(M_Z)=0.1171(7)$, ${\overline{m}}_c=1281.1(3.8)$ MeV and ${\overline{m}}_b=4174.3(9.5)$ MeV.

   hep-phhep-latNucl.Part.Phys.Proc.(2024)·1 citation
3. 03*

   Constraints on Asymmetric Dark Matter Self Annihilation Cross Sections in Non-standard Cosmological Scenarios

   Fangyu Liu🇨🇳 · Hoernisa Iminniyaz🇨🇳

   We investigate the relic abundance of asymmetric dark matter in the non-standard cosmological scenarios when the annihilation cross section includes self annihilations. Here we discuss the kination model and brane world cosmology. When the self annihilation is permitted for asymmetric dark matter, there is possibility of washing out the pre-existed asymmetry. We find the constraints on the cross section to avoid the complete washing out of the asymmetry in the non-standard cosmological scenarios. The enhanced cosmic expansion rate causes the freeze out point of wash-out to be earlier. The larger self annihilation cross sections are allowed to exist in kination model and brane world cosmology. Then, in the case of left-handed sneutrino asymmetric dark matter, we find the value of the lower bound on winos mass is smaller than that in the standard cosmological scenario.

   hep-phChin.J.Phys.(2024)·1 citation
4. 04*

   Axion detection via superfluid ${}^3$He ferromagnetic phase and quantum measurement techniques

   So Chigusa🇺🇸 · Dan Kondo🇯🇵 · Hitoshi Murayama🇺🇸 · Risshin Okabe🇯🇵 · Hiroyuki Sudo🇯🇵

   We propose to use the nuclear spin excitation in the ferromagnetic A1 phase of the superfluid ${}^3$He for the axion dark matter detection. This approach is striking in that it is sensitive to the axion-nucleon coupling, one of the most important features of the QCD axion introduced to solve the strong CP problem. We review a quantum mechanical description of the nuclear spin excitation and apply it to the estimation of the axion-induced spin excitation rate. We also describe a possible detection method of the spin excitation in detail and show that the combination of the squeezing of the final state with the Josephson parametric amplifier and the homodyne measurement can enhance the sensitivity. It turns out that this approach gives good sensitivity to the axion dark matter with the mass of $O(1)\mu \mathrm{eV}$ depending on the size of the external magnetic field. We estimate the parameters of experimental setups, e.g., the detector volume and the amplitude of squeezing, required to reach the QCD axion parameter space.

   hep-phcond-mat.supr-conhep-exJHEP(2024)·9 citations
5. 05*

   The $U(1{)}_{L_{\mu }-L_{\tau }}$ breaking phase transition, muon $g-2$, dark matter, collider and gravitational wave

   Jie Wang🇨🇳 · Jinghong Ma🇨🇳 · Jing Gao🇨🇳 · Xiao-Fang Han🇨🇳 · Lei Wang🇨🇳

   Combining the dark matter and muon $g-2$ anomaly, we study the $U(1{)}_{L_{\mu }-L_{\tau }}$ breaking phase transition, gravitational wave spectra, and the direct detection at the LHC in an extra $U(1{)}_{L_{\mu }-L_{\tau }}$ gauge symmetry extension of the standard model. The new fields includes vector-like leptons ($E_1,E_2,N$), $U(1{)}_{L_{\mu }-L_{\tau }}$ breaking scalar $S$ and gauge boson $Z^{\prime }$, as well as the dark matter candidate $X_I$ and its heavy partner $X_R$. A joint explanation of the dark matter relic density and muon $g-2$ anomaly excludes the region where both $min(m_{E_1},m_{E_2},m_N,m_{X_R})$ and $min(m_{Z^{\prime }},m_S)$ are much larger than $m_{X_I}$. In the parameter space accommodating the DM relic density and muon $g-2$ anomaly, the model can achieve a first order $U(1{)}_{L_{\mu }-L_{\tau }}$ breaking phase transition, whose strength is sensitive to the parameters of Higgs potential. The corresponding gravitational wave spectra can reach the sensitivity of U-DECIGO. In addition, the direct searches at the LHC impose stringent bound on the mass spectra of the vector-like leptons and dark matter.

   hep-phCPC(2024)·2 citations
6. 06*

   Probing invisible vector meson decay mode with hadronic beam in the NA64 experiment at SPS/CERN

   Alexey S. Zhevlakov🇷🇺 · Dmitry V. Kirpichnikov🇷🇺 · Sergei N. Gninenko🇷🇺 · Sergey Kuleshov🇨🇱 · Valery E. Lyubovitskij🇩🇪

   We test a novel idea of using a ${\pi }^{-}$ beam in the fixed-target experiments to search for New Physics in the events with missing energy. Bounds for invisible vector $\rho$ meson decay were derived, analyzed, and compared with the current limits on searching Dark Matter in the accelerator based experiments. We demonstrate that the new approach can be effective tool to probe sub-GeV Dark Matter parameter space.

   hep-phPRD(2023)·10 citations
7. 07*

   Electron electric dipole moment and electroweak baryogenesis in a complex singlet extension of the Standard Model with degenerate scalars

   Chikako Idegawa🇯🇵 · Eibun Senaha

   We study the possibility of electroweak baryogenesis in the standard model with a complex scalar field, focusing mainly on a degenerate scalar scenario. In our setup, CP violation is provided by dimensional-5 Yukawa interactions involving the complex scalar field. In contrast to previous studies in the literature, we exemplify a case in which a complex phase in the singlet scalar potential is transmitted to the fermion sector via the higher-dimensional operators and drives BAU. We point out that an electric dipole moment of the electron can be suppressed due to the Higgs mass degeneracy and the presence of a new electron Yukawa coupling. Thus, viable parameter space for electroweak baryogenesis is still wide open for the latest experimental bound set by the JILA Collaboration.

   hep-phPLB(2024)·12 citations
8. 08*

   Correlations of dihadron polarization in central, peripheral and ultraperipheral heavy-ion collisions

   Xiaowen Li🇨🇳 · Zhao-Xuan Chen🇨🇳 · Shanshan Cao🇨🇳 · Shu-Yi Wei🇨🇳

   While jet quenching in relativistic heavy-ion collisions has been extensively studied over decades, the polarization of quenched hadrons has rarely been discussed. It has recently been proposed that the correlations of dihadron polarization in $e^{+}{e}^{-}$ and $pp$ collisions provide a novel probe of the longitudinal spin transfer from hard partons to hadrons without requiring the colliding beams to be polarized. To support realistic experimental measurement of dihadron polarization with sufficient luminosity, we extend the aforementioned study to relativistic heavy-ion collisions by convoluting the vacuum fragmentation of partons with their energy loss inside the quark-gluon plasma (QGP). We find that while the correlation functions of $\Lambda$-$\Lambda$ (or $\Lambda$-$\bar{\Lambda }$) polarization in peripheral collisions is consistent with those in $pp$ collisions, clear enhancement can be seen in central collisions. These correlation functions appear sensitive to different assumptions in the DSV parameterization of parton fragmentation functions, and therefore could place additional constraints on the spin-dependent fragmentation functions of quarks and gluons. The correlation of dihadron polarization has also been explored in ultraperipheral heavy-ion collisions, which provides a cleaner probe of fragmentation functions of quarks produced by energetic photon-photon and photon-pomeron interactions.

   hep-phhep-exPRD(2024)·15 citations
9. 09*

   Effect of event classifiers on jet quenching-like signatures in high-multiplicity $p+p$ collisions at $\sqrt{s}=13$ TeV

   Hushnud Hushnud🇮🇳 · Omveer Singh · Srikanta Kumar Tripathy🇵🇱 · Aditya Nath Mishra🇮🇳 · Kalyan Dey🇮🇳

   The motivation behind exploring jet quenching-like phenomena in small systems arises from the experimental observation of heavy-ion-like behavior of particle production in high-multiplicity proton-proton ($p+p$) collisions. Quantifying the jet quenching in $p+p$ collisions is a challenging task, as the magnitude of the nuclear modification factor ($R_{\mathrm{AA}}$ or $R_{\mathrm{CP}}$), which is used to quantify jet quenching, is influenced by several factors, such as the estimation of centrality and the scaling factor. The most common method of centrality estimation employed by the ALICE collaboration is based on measuring charged-particle multiplicity with the V0 detector situated at the forward rapidity. This technique of centrality estimation makes the event sample biased towards hard processes like multijet final states. This bias of the V0 detector towards hard processes makes it difficult to study the jet quenching effect in high-multiplicity $p+p$ collisions. In the present article, we propose to explore the use of a new and robust event classifier, flattenicity which is sensitive to both the multiple soft partonic interactions and hard processes. The ${\mathcal{P}}_{\mathrm{CP}}$, a quantity analogous to $R_{\mathrm{CP}}$, has been estimated for high-multiplicity $p+p$ collisions at $\sqrt{s}=13$ TeV using \texttt{PYTHIA8} model for both the V0M (the multiplicity classes selected based on V0 detector acceptance) as well as flattenicity. The evolution of ${\mathcal{P}}_{\mathrm{CP}}$ with $p_{\mathrm{T}}$ shows a heavy-ion-like effect for flattencity which is attributed to the selection of softer transverse momentum particles in high-multiplicity $p+p$ collisions.

   hep-ph0 citations
10. 10*

    The LHC as a Neutrino-Ion Collider

    Juan M. Cruz-Martinez🇨🇭 · Max Fieg🇺🇸 · Tommaso Giani🇳🇱 · Peter Krack🇳🇱 · Toni Mäkelä🇵🇱 · Tanjona Rabemananjara🇳🇱 · Juan Rojo🇳🇱

    Proton-proton collisions at the LHC generate a high-intensity collimated beam of neutrinos in the forward (beam) direction, characterised by energies of up to several TeV. The recent observation of LHC neutrinos by FASER$\nu$ and SND@LHC signals that this hitherto ignored particle beam is now available for scientific inquiry. Here we quantify the impact that neutrino deep-inelastic scattering (DIS) measurements at the LHC would have on the parton distributions (PDFs) of protons and heavy nuclei. We generate projections for DIS structure functions for FASER$\nu$ and SND@LHC at Run III, as well as for the FASER$\nu$2, AdvSND, and FLArE experiments to be hosted at the proposed Forward Physics Facility (FPF) operating concurrently with the High-Luminosity LHC (HL-LHC). We determine that up to one million electron- and muon-neutrino DIS interactions within detector acceptance can be expected by the end of the HL-LHC, covering a kinematic region in $x$ and $Q^2$ overlapping with that of the Electron-Ion Collider. Including these DIS projections into global (n)PDF analyses, specifically PDF4LHC21, NNPDF4.0, and EPPS21, reveals a significant reduction of PDF uncertainties, in particular for strangeness and the up and down valence PDFs. We show that LHC neutrino data enables improved theoretical predictions for core processes at the HL-LHC, such as Higgs and weak gauge boson production. Our analysis demonstrates that exploiting the LHC neutrino beam effectively provides CERN with a "Neutrino-Ion Collider" without requiring modifications in its accelerator infrastructure.

    hep-phhep-exnucl-exnucl-thEPJC(2024)·71 citations
11. 11*

    On the high-energy instability of quarkonium production

    Maxim Nefedov🇫🇷

    The perturbative instability of NLO collinear factorisation (CF) computations of $p_T$-integrated cross sections of heavy quarkonium production at high hadronic or photon-hadron collision energy is discussed. We resolve this problem via the matching of NLO CF computation with the resummation of higher-order corrections $\propto {\alpha }_s^n{\ln }^{n-1}(\hat{s}/M^2)$ at high partonic center of mass energies $\hat{s}\gg M^2$. The resummation is performed in the Doubly-Logarithmic Approximation(DLA) of High-Energy Factorisation(HEF) formalism. We also report the results of the first computation of one-loop corrections to impact-factors involving heavy quark-antiquark pair in the intermediate states considered in the Non-Relativistic QCD (NRQCD) factorisation formalism for quarkonium production: $Q\bar{Q}\left[{}^1{S}_0^{[8]}\right]$ and $Q\bar{Q}\left[{}^1{S}_0^{[1]}\right]$. These results are necessary for the extension of our resummation formalism beyond DLA.

    hep-phhep-exNucl.Part.Phys.Proc.(2024)·4 citations
12. 12*

    Effectively flat potential in the Friedberg-Lee-Sirlin model

    Eduard Kim🇷🇺 · Emin Nugaev🇷🇺

    The Friedberg-Lee-Sirlin (FLS) model is a well-known renormalizable theory of scalar fields that provides for the existence of non-topological solitons. Since this model was proposed, numerous works have been dedicated to studying its classical configurations and its general suitability for various physical problems in cosmology, quantum chromodynamics, etc. In this paper, we study how Q-balls in effective field theory (EFT) reproduce non-topological solitons in full FLS theory. We obtain an analytical description of the simplified model and compare results with numerical calculations and perturbation theory. We also study the condensation of charged bosons on the domain wall. A full numerical solution allows us to check the EFT methods for this problem. The latter analysis is based on the application of EFT methods to significantly inhomogeneous configurations. We give an interpretation of the results in terms of the shifted boson mass and the vacuum rearrangement.

    hep-phhep-thEPJC(2024)·7 citations
13. 13*

    Dynamical Chiral Symmetry Breaking in Quantum Chromo Dynamics: Delicate and Intricate

    Reinhard Alkofer🇦🇹

    Dynamical Chiral Symmetry Breaking (DCSB) in Quantum Chromo Dynamics (QCD) for the light quarks is an indispensable concept for understanding hadron physics, i.e., the spectrum and the structure of hadrons. In Functional Approaches to QCD the respective role of the quark propagator has been evident since the seminal work of Nambu and Jona-Lasinio has been recast in QCD's terms. It not only highlights one of the most important aspects of DCSB, the dynamical generation of constituent quark masses, but also makes plausible that DCSB is a robustly occurring phenomenon in QCD. The latter impression, however, changes when higher $n$-point functions are taken into account. In particular, the quark-gluon vertex, i.e., the most elementary $n$-point function describing the full, non-perturbative quark-gluon interaction, plays a dichotomous role: It is subject to DCSB as signalled by its scalar and tensor components but it is also a driver of DCSB due to the infrared enhancement of most of its components. Herein, the relevant self-consistent mechanism is elucidated. It is pointed out that recently obtained results imply that, at least in the covariant gauge, DCSB in QCD is located close to the critical point and is thus a delicate effect. And, requiring a precise determination of QCD's three-point functions, DCSB is established, in particular in view of earlier studies, by an intricate interplay of the self-consistently determined magnitude and momentum dependence of various tensorial components of the gluon-gluon and the quark-gluon interactions.

    hep-phSymmetry(2023)·10 citations
14. 14*

    Triangle and box diagrams in coupled-channel systems from the chiral Lagrangian

    Tobias Isken🇩🇪 · Xiao-Yu Guo🇨🇳 · Yonggoo Heo🇩🇪 · Csaba L. Korpa🇭🇺 · Matthias F.M. Lutz🇩🇪

    We perform an analysis of triangle- and box-loop contributions to the generalized potential in the scattering of Goldstone bosons off the J^P= 0^- and 1^- charmed mesons. Particular emphasis is put on the use of on-shell mass parameters in such contributions in terms of a renormalization scheme that ensures the absence of power-counting violating terms. This is achieved with a systematically extended set of Passarino--Veltman basis functions, that leads to manifest power-counting conserving one-loop expressions and avoids the occurrence of superficial kinematical singularities. Compact expressions to chiral order three and four are presented that are particularly useful in coding such coupled-channel systems. Our formal results are generic and prepare analogous computations for other systems, like meson-baryon scattering from the chiral Lagrangian.

    hep-phnucl-thPRD(2024)·8 citations
15. 15*

    Probing Light DM through Migdal Effect with Spherical Proportional Counter

    Yuchao Gu🇨🇳 · Jie Tang🇨🇳 · Lei Wu🇨🇳 · Bin Zhu🇨🇳

    Owing to its low electronic noise and flexible target materials, the Spherical Proportional Counter (SPC) with a single electron detection threshold can be utilized to search for sub-GeV dark matter (DM). In this work, we investigate the prospects for light DM direct detection through the DM-nucleus Migdal effect in the DARKSPHERE detector. We consider the different DM velocity distributions and momentum-transfer effects. For Xenon and Neon targets, we find that the DM mass $m_{DM}$ can be probed down to as low as $m_{DM}\sim \mathcal{O}$(10) MeV, and the derived bounds on the DM-nucleus scattering cross section ${\bar{\sigma }}_n$ are sensitive to the high-velocity tails of the DM velocity distribution, which can be altered by orders of magnitude for the different DM velocity distributions in the region $m_{DM}<10$ MeV.

    hep-phCPC(2023)·10 citations
16. 16*

    Heavy resonances and the oblique parameters S and T

    Ignasi Rosell🇪🇸 · Antonio Pich🇪🇸 · Juan Jose Sanz-Cillero🇪🇸

    It has been confirmed experimentally the existence of a mass gap between Standard Model (SM) and eventual Beyond Standard Model (BSM) fields. Therefore, the use of effective approaches to search for fingerprints of New Physics is very appealing. A non-linear realizations of the Electroweak Symmetry Breaking is considered here, where the Higgs is a singlet with free couplings and the SM fields are also coupled to bosonic heavy resonances. A one-loop-level calculation of the oblique S and T parameters is presented here. This analysis allows us to constrain resonance masses to be above the TeV scale, $M_R>3$TeV, in good agreement with our previous determinations, where these observables were computed with a more simplified Lagrangian.

    hep-phNucl.Part.Phys.Proc.(2024)·3 citations
17. 17*

    The NFLikelihood: an unsupervised DNNLikelihood from Normalizing Flows

    Humberto Reyes-Gonzalez🇮🇹 · Riccardo Torre🇮🇹

    We propose the NFLikelihood, an unsupervised version, based on Normalizing Flows, of the DNNLikelihood proposed in Ref.[1]. We show, through realistic examples, how Autoregressive Flows, based on affine and rational quadratic spline bijectors, are able to learn complicated high-dimensional Likelihoods arising in High Energy Physics (HEP) analyses. We focus on a toy LHC analysis example already considered in the literature and on two Effective Field Theory fits of flavor and electroweak observables, whose samples have been obtained throught the HEPFit code. We discuss advantages and disadvantages of the unsupervised approach with respect to the supervised one and discuss possible interplays of the two.

    hep-phcs.LGhep-exSciPost Phys.Core(2024)·6 citations
18. 18*

    Exclusive photoproduction of $D$-meson pairs with large invariant mass

    Marat Siddikov🇨🇱 · Iván Schmidt🇨🇱

    In this paper we analyze the exclusive photoproduction of the $D$-meson pairs with large invariant mass. We perform evaluations in the collinear factorization framework and in the leading order of the strong coupling ${\alpha }_s$, expressing the cross-section in terms of generalized parton distributions (GPDs) of different parton flavors in the proton. We focus on the photoproduction of the pseudoscalar-vector pairs, like e.g. $D^{\pm }{D}^{\ast \mp }$, $D^0{\overline{D}}^{\ast 0}$, $D_s^{+}{D}_s^{\ast -}$, which gets the dominant contribution from the chiral even GPDs of the target, and estimate the cross-section in the kinematics of the future Electron Ion Collider (EIC). In all channels the amplitude of the process obtains comparable contributions from gluons and only one of the light quark flavors. This finding signals that the process potentially could be used to single out the contributions of the individual chiral even GPDs of light flavors. We found that the process is mostly sensitive to the behavior of GPDs in the so-called Efremov-Radyushkin-Brodsky-Lepage (ERBL) region. Numerically, the cross-section of the process is sufficiently large for experimental studies and thus can be used as a complementary probe for studies of the partons GPDs.

    hep-phPRD(2023)·16 citations
19. 19*

    Detecting High-Energy Neutrinos from Galactic Supernovae with ATLAS

    Alex Y. Wen🇺🇸 · Carlos A. Argüelles🇺🇸 · Ali Kheirandish🇺🇸 · Kohta Murase🇺🇸

    We show that ATLAS, a collider detector, can measure the flux of high-energy supernova neutrinos, which can be produced from days to months after the explosion. Using Monte Carlo simulations for predicted fluxes, we find at most $\mathcal{O}(0.1-1)$ starting events and $\mathcal{O}(10-100)$ throughgoing events from a supernova 10 kpc away. Possible Galactic supernovae from Betelgeuse and Eta Carinae are further analyzed as demonstrative examples. We argue that even with limited statistics, ATLAS has the ability to discriminate among flavors and between neutrinos and antineutrinos, making it an unique neutrino observatory so far unmatched in this capability.

    hep-phastro-ph.HEhep-exPRL(2024)·10 citations
20. 20*

    Possible large CP violation in charmed ${\Lambda }_b$ decays

    Yin-Fa Shen🇨🇳 · Jian-Peng Wang🇨🇳 · Qin Qin🇨🇳

    We propose that the cascade decay ${\Lambda }_b\to D(\to K^{+}{\pi }^{-})N(\to p{\pi }^{-})$ may serve as the discovery channel for baryonic CP violation. This decay chain is contributed by, dominantly, the amplitudes with the intermediate $D$ state as $D^0$ or ${\bar{D}}^0$. The large weak phase between the two kinds of amplitudes suggests the possibility of significant CP violation. While the presence of undetermined strong phases may complicate the dependence of CP asymmetry, our phenomenological analysis demonstrates that CP violation remains prominent across a broad range of strong phases. The mechanism also applies to similar decay modes such as ${\Lambda }_b\to D(\to K^{+}{K}^{-})\Lambda$. Considering the anticipated luminosity of LHCb, we conclude that these decay channels offer a promising opportunity to uncover CP violation in the baryon sector.

    hep-phPRD(2023)·9 citations
21. 21*

    Cut structures and an observable singularity in the three-body threshold dynamics: the $T_{cc}^{+}$ case

    Jun-Zhang Wang🇨🇳 · Zi-Yang Lin🇨🇳 · Shi-Lin Zhu🇨🇳

    The three-body threshold effect, the distinctive and intriguing non-perturbative dynamics in the low-energy hadron-hadron scattering, has acquired compelling significance in the wake of the recent observation of the double-charm tetraquark $T_{cc}^{+}$. This dynamics is characterized by the emergence of singular points and branch cuts within the interaction potential, occurring when the on-shell condition of the mediated particle is satisfied. The presence of these potential singularities indicates that the system is no longer Hermitian and also poses intractable challenges in obtaining exact solutions for dynamical scattering amplitudes. In this work, we develop a complex scaled Lippmann-Schwinger equation as an operation of analytical continuation of the $T$ matrix to resolve this problem. Through a practical application to the $D{D}^{\ast }\to D{D}^{\ast }$ process, we reveal complicated cut structures of the three-body threshold dynamics in the complex plane, primarily stemming from the one-pion exchange. Notably, our methodology succeeds in reproducing the $T_{cc}^{+}$ structure, in alignment with the quasi-bound pole derived from the complex scaling method within the Schrödinger equation framework. More remarkably, after solving the on-shell $T$ matrix on the positive real axis of momentum plane, we find an extra new structure in the $D{D}^{\ast }$ mass spectrum, which arises from a right-hand cut at a physical pion mass and should be observable in Lattice QCD simulations and future high-energy experiments.

    hep-phhep-latnucl-thPRD(2024)·15 citations
22. 22*

    Analysis of $b\to c\tau {\bar{\nu }}_{\tau }$ anomalies using weak effective Hamiltonian with complex couplings

    Muhammad Arslan🇵🇰 · Tahira Yasmeen🇵🇰 · Saba Shafaq🇵🇰 · Ishtiaq Ahmed🇵🇰 · Muhammad Jamil Aslam🇵🇰

    Recently, the experimental measurements of the branching ratios and different polarization asymmetries for the processes occurring through flavor-changing-charged current $b\to c\tau {\overline{\nu }}_{\tau }$ transitions by BABAR, Belle, and LHCb show some sparkling differences with the corresponding SM predictions. Assuming the left handed neutrinos, we add the dimension-six vector, (pseudo-)scalar, and tensor operators with complex WCs to the SM WEH. Together with 60%, 30% and 10% constraints coming from the branching ratio of $B_c\to \tau {\bar{\nu }}_{\tau }$, we analyze the parametric space of these new physics WCs accommodating the current anomalies in the purview of the most recent HFLAV data of $R_{\tau /\mu ,e}\left(D\right)$, $R_{\tau /\mu ,e}\left(D^{\ast }\right)$ and Belle data of $F_L\left(D^{\ast }\right)$ and $P_{\tau }\left(D^{\ast }\right)$. Furthermore, we derive the sum rules which correlate these observables with $R_{\tau /\mu ,e}\left(D\right)$ and $R_{\tau /\mu ,e}\left(D^{\ast }\right)$. Using the best-fit points of the new complex WCs along with the latest measurements of $R_{\tau /\mu ,e}\left(D^{(\ast )}\right)$, we predict the numerical values of the observable $R_{\tau /\ell }\left({\Lambda }_c\right)$, $R_{\tau /\mu }\left(J/\psi \right)$ and $R_{\tau /\ell }\left(X_c\right)$ from the sum rules. Apart from finding the correlation matrix among the observables under consideration, we plot them graphically which is useful to discriminate different NP scenarios. Finally, we study the impact of these NP couplings on various angular and the CP triple product asymmetries, that could be measured in some ongoing and future experiments. The precise measurements of these observables are important to check the SM and extract the possible NP.

    hep-phhep-exhep-latCPC(2024)·5 citations
23. 23*

    Gravitational Wave Resonance in Ultra-Light Dark Matter Halos

    Paola C. M. Delgado🇵🇱

    Ultra-Light Dark Matter (ULDM) halos constituted by Ultra-Light Axions (ULAs) generate gravitational potentials that oscillate in time. In this paper I show these potentials interact with gravitational waves, resonantly amplifying them. For all ULA masses considered, the resonance in the solar region is currently negligible, while in a denser dark matter environment, which may arise in different scenarios, it might become significant. The frequency of the amplified gravitational wave is equal to the ULA mass in the case of first resonance band, which represents the most efficient scenario.

    hep-phastro-ph.COgr-qcPRD(2023)·8 citations
24. 24*

    A Resolution of the Monopole Problem in the R_h=ct Universe

    Fulvio Melia🇺🇸

    Spontaneous symmetry breaking in grand unified theories is thought to have produced an exceedingly large number of magnetic monopoles in the early Universe. In the absence of suppression or annihilation, these very massive particles should be dominating the cosmic energy budget today, but none has ever been found. Inflation was invented in part to dilute their number, thereby rendering their density undetectable by current instruments. Should the inflationary paradigm not survive, however, the ensuing disagreement between theory and observation would constitute a cosmological `monopole problem' and create further tension for any extension to the standard model of particle physics. But as is also true for all horizon problems, a monopole overabundance emerges only in cosmologies with an initial period of deceleration. We show that the alternative Friedmann-Lemaitre-Robertson-Walker cosmology known as the R_h=ct universe completely eliminates all such anomalies rather trivially and naturally, without the need for an inflated expansion. We find that the monopole energy density today would be completely undetectable in R_h=ct. Evidence continues to grow that the zero active mass condition from general relativity ought to be an essential ingredient in LCDM.

    hep-phastro-ph.COgr-qcPhys.Dark Univ.(2023)·6 citations
25. 25*

    Searching for axion forces with spin precession in atoms and molecules

    Prateek Agrawal🇬🇧 · Nicholas R. Hutzler🇺🇸 · David E. Kaplan🇺🇸 · Surjeet Rajendran🇺🇸 · Mario Reig🇬🇧

    We propose to use atoms and molecules as quantum sensors of axion-mediated monopole-dipole forces. We show that electron spin precession experiments using atomic and molecular beams are well-suited for axion searches thanks to the presence of co-magnetometer states and single-shot temporal resolution. Experimental strategies to detect axion gradients from localised sources and the earth are presented, taking ACME III as a prototype example. Other possibilities including atomic beams, and laser-cooled atoms and molecules are discussed.

    hep-phphysics.atom-phJHEP(2024)·15 citations
26. 26*

    Custodial Symmetry Breaking and Higgs Signatures at the LHC

    Jon Butterworth🇬🇧 · Hridoy Debnath🇺🇸 · Pavel Fileviez Perez🇺🇸 · Francis Mitchell🇬🇧

    We discuss the simplest model that predicts a tree level modification of the $\rho$ parameter from a shift in the $W$-mass without changing the prediction for the $Z$ mass. This model predicts a new neutral Higgs and two charged Higgses, with very similar masses and suppressed couplings to the Standard Model fermions. We discuss the decay properties of these new scalar bosons, and the main signatures at the Large Hadron Collider. Comparing these signatures for the first time to the latest measurements, we show that while masses around 200 GeV are excluded for some scenarios, over a wide range of model parameter space the new bosons can have a mass close to the electroweak scale without violating existing limits from experimental searches or destroying the agreement with measurements. We investigate the scenario where the new neutral Higgs is fermiophobic and has a large branching ratio into $W$ gauge bosons and/or photons, and show that this could lead to a signal in the diphoton mass spectrum at low Higgs masses. We discuss the different signatures that can motivate new measurements and searches at the Large Hadron Collider.

    hep-phhep-exPRD(2024)·16 citations
27. 27*

    Neutrinos from Earth-Bound Dark Matter Annihilation

    Maxim Pospelov🇺🇸 · Anupam Ray🇺🇸

    A sub-component of dark matter with a short collision length compared to a planetary size leads to efficient accumulation of dark matter in astrophysical bodies. We analyze possible neutrino signals from the annihilation of such dark matter and conclude that in the optically thick regime for dark matter capture, the Earth provides the largest neutrino flux. Using the results of the existing searches, we consider two scenarios for the neutrino flux, from stopped mesons and prompt higher-energy neutrinos. In both cases we exclude some previously unexplored parts of the parameter space (dark matter mass, its abundance, and the scattering cross section on nuclei) by recasting the existing neutrino searches.

    hep-phastro-ph.COastro-ph.EPJCAP(2024)·13 citations
28. 28*

    X-rays constraints on sub-GeV Dark Matter

    Jordan Koechler🇫🇷

    We present updated constraints on 'light' Dark Matter (DM) particles with masses between 1 MeV and 5 GeV. In this range, we can expect DM-produced $e^{\pm }$ pairs to up-scatter low-energy ambient photons in the Milky Way via the Inverse Compton process, and produce a flux of X-rays that can be probed by a range of space observatories. Using diffuse X-ray data from XMM-Newton, INTEGRAL, NuSTAR and Suzaku, we compute the strongest constraints to date on annihilating DM for 200 MeV $<m_{\mathrm{DM}}<$ 5 GeV and decaying DM for 100 MeV $<m_{\mathrm{DM}}<$ 5 GeV.

    hep-phastro-ph.COastro-ph.HEPoS(2024)·11 citations
29. 29*

    Medium modification of pion production in low energy Au+Au collisions

    Christian Kummer🇩🇪 · Kai Gallmeister🇩🇪 · Lorenz von Smekal🇩🇪

    There is a major mismatch between the charged pion yields in Au+Au collisions at low energies calculated by various transport models and the experimental measured values from the Hades collaboration. In this work, reasonable improvements on the equation of state, in-medium modification of cross sections, and the influence of the nuclear potential for Delta resonances will be investigated in the framework of the GiBUU transport model. As a result, we demonstrate that theoretical calculations can indeed describe the charged pion yields measured by Hades for Au+Au collisions rather well, but that a mismatch then remains between calculations and data for the yields of neutral pions extracted from dileptons within the same experiment.

    ↳ nucl-thhep-phPRC(2024)·6 citations
30. 30*

    Energy-dependent flavour ratios in neutrino telescopes from charm

    Atri Bhattacharya🇧🇪 · Rikard Enberg🇸🇪 · Mary Hall Reno🇺🇸 · Ina Sarcevic🇺🇸

    The origin of the observed diffuse neutrino flux is not yet known. Studies of the relative flavour content of the neutrino flux detected at Earth can give information on the production mechanisms at the sources and on flavour mixing, complementary to measurements of the spectral index and normalisation. Here we demonstrate the effects of neutrino fluxes with different spectral shapes and different initial flavour compositions dominating at different energies, and we study the sensitivity of future measurements with the IceCube Neutrino Observatory. Where one kind of flux gives way to another, this shows up as a non-trivial energy dependence in the flavour compositions. We explore this in the context of slow-jet supernovae and magnetar-driven supernovae -- two examples of astrophysical sources where charm production may be effective. Using current best-fit neutrino mixing parameters and their projected 2040 uncertainties, we use event ratios of different event morphologies at IceCube to illustrate the possibilities of distinguishing the energy dependence of neutrino flavour ratios.

    ↳ astro-ph.HEhep-phJCAP(2024)·9 citations
31. 31*

    Search for the production of dark gauge bosons in the framework of Einstein-Cartan portal in the simulation of proton-proton collisions at $\sqrt{s}=13.6$ TeV

    S. Elgammal🇪🇬

    In this study, we investigate the potential production of a heavy torsion field (TS) at the LHC, which stems from a simplified model rooted in Einstein-Cartan gravity, in connection with dark matter. Within this framework, the torsion field is capable of decaying into pairs of dark matter (DM) particles. Notably, one of these DM particles is heavy enough to decay into dark neutral gauge bosons (A${}^{\prime }$) alongside another DM particle. The Analysis has been performed by studying events with dimuon plus missing transverse energy produced in the simulated proton-proton collisions at the Large Hadron Collider, at 13.6 TeV center of mass energy and integrated luminosity of 52 fb${}^{-1}$ corresponding to the LHC run 3 circumstances during 2022 and 2023. We provide upper limits, in case no new physics has been discovered, on the masses of various particles in the model as (A${}^{\prime }$), as well as the heavy mediator (torsion field).

    ↳ hep-exhep-phChin.J.Phys.(2025)·1 citation
32. 32*

    Study of the effects of external imaginary electric field and chiral chemical potential on quark matter

    Ji-Chong Yang🇨🇳 · Xin Zhang🇨🇳 · Jian-Xing Chen🇨🇳

    The behavior of quark matter with both external electric field and chiral chemical potential is theoretically and experimentally interesting to consider. In this paper, the case of simultaneous presence of imaginary electric field and chiral chemical potential is investigated using the lattice QCD approach with $N_f=1+1$ dynamical staggered fermions. We find that overall both the imaginary electric field and the chiral chemical potential can exacerbate chiral symmetry breaking, which is consistent with theoretical predictions. However we also find a non-monotonic behavior of chiral condensation at specific electric field strengths and chiral chemical potentials. In addition to this, we find that the behavior of Polyakov loop in the complex plane is not significantly affected by chiral chemical potential in the region of the parameters consider in this paper.

    ↳ hep-latcs.NAhep-phmath.NA+1EPJC(2024)·6 citations
33. 33*

    Analytical structure of the binary collision integral and the ultrarelativistic limit of transport coefficients of an ideal gas

    David Wagner🇩🇪 · Victor E. Ambrus🇷🇴 · Etele Molnar🇩🇪

    In this paper we discuss the analytical properties of the binary collision integral for a gas of ultrarelativistic particles interacting via a constant cross-section. Starting from a near-equilibrium expansion over a complete basis of irreducible tensors in momentum space we compute the linearized collision matrices analytically. Using these results we then numerically compute all transport-coefficients of relativistic fluid dynamics with various power-counting schemes that are second-order in Knudsen and/or inverse Reynolds numbers. Furthermore, we also exactly compute the leading-order contribution with respect to the particle mass to the coefficient of bulk viscosity, the relaxation time, and other second-order transport coefficients of the bulk viscous pressure.

    ↳ physics.flu-dynhep-phnucl-thPRD(2024)·16 citations
34. 34*

    Dark matter searches in dwarf spheroidal galaxies with the Cherenkov Telescope Array

    Francesco Gabriele Saturni · Michele Doro · Aldo Morselli · Gonzalo Rodríguez-Fernández (for the CTA Consortium)

    Dark matter (DM) is one of the major components in the Universe. However, at present its existence is still only inferred through indirect astronomical observations. DM particles can annihilate or decay, producing final-state Standard Model pairs that subsequently annihilate into high-energy $\gamma$-rays. The dwarf spheroidal galaxies (dSphs) in the Milky Way DM halo have long been considered optimal targets to search for annihilating DM signatures in GeV-to-TeV $\gamma$-ray spectra due to their high DM densities (hence high astrophysical factors), as well as the expected absence of intrinsic $\gamma$-ray emission of astrophysical origin. For such targets, it is important to compute the amount of DM in their halos in a consistent way to optimize the $\gamma$-ray data analysis. Such estimates directly affect the observability of DM signals in dSphs, as well as the DM constraints that can be derived in case of null detection. In this contribution, we present the results on the sensitivity of the Cherenkov Telescope Array (CTA) for DM annihilation and decay searches using planned observations of the Milky Way dSphs. We select the most promising targets among all presently known dwarf satellites, providing new determinations of their expected DM signal. This study shows an improvement of approximately an order of magnitude in sensitivity compared to current searches in similar targets. We also discuss the results in terms of cuspy and cored DM models, and investigate the sensitivity obtained by the combination of observations from different dSphs. Finally, we explore the optimal strategies for CTA observations of dSphs.

    ↳ astro-ph.HEastro-ph.IMhep-phPoS(2023)·5 citations
35. 35*

    Lattice Correlation Functions from Differential Equations

    Federico Gasparotto🇩🇪 · Andreas Rapakoulias🇩🇪 · Stefan Weinzierl🇩🇪 · Xiaofeng Xu🇩🇪

    We discuss how methods developed in the context of perturbation theory can be applied to the computation of lattice correlation functions, in particular in the non perturbative regime. The techniques we consider are integration-by-parts identities (supplemented with symmetry relations) and the method of differential equations, cast in the framework of twisted co-homology. We report on calculations of correlation functions for a scalar $\lambda {\varphi }^4$ theory and lattices of small size, both in Euclidean and Minkowskian signature.

    ↳ hep-thhep-lathep-phPoS(2024)·0 citations
36. 36*

    Radiative transition decay width of ${\psi }_2(3823)\to \gamma {\chi }_{c1}$ from lattice QCD

    Ning Li🇨🇳 · Yan Gao🇨🇳 · Feiyu Chen🇨🇳 · Ying Chen🇨🇳 · Xiangyu Jiang🇨🇳 · Chunjiang Shi🇨🇳 · Wei Sun🇨🇳

    We present an exploratory $N_f=2$ lattice QCD study of ${\psi }_2(3823)\to \gamma {\chi }_{c1}$ at a pion mass $m_{\pi }\approx 350$~MeV. The related two-point and three-piont functions are calculated using the distillation method. The electromagnetic multipole form factor $\hat{V}(0)=2.083(11)$ for $J/\psi \to \gamma {\eta }_c$ is consistent with previous lattice results, the form factors ${\hat{E}}_1(0)$, ${\hat{M}}_2(0)$ and ${\hat{E}}_3(0)$ for $\Gamma ({\chi }_{c2}\to \gamma J/\psi )$ have the same hierarchy as that derived from experiments and the predicted decay width $\Gamma ({\chi }_{c2}\to \gamma J/\psi )=368(5)\text{keV}$ is in excellent agreement with the PDG value $374(10)\text{keV}$ and previous lattice QCD results in the quenched approximation. The same strategy is applied to the study of the process ${\psi }_2(3823)\to \gamma {\chi }_{c1}$ and the partial decay width is predicted to be $337(27)\text{keV}$. According to the BESIII constraints on the ${\psi }_2(3823)$ decay channels and some phenomenological results, we estimate the total width $\Gamma ({\psi }_2(3823))=520(100)\text{keV}$.

    ↳ hep-lathep-phPRD(2024)·6 citations
37. 37*

    TeV gamma-ray sensitivity to velocity-dependent dark matter models in the Galactic Center

    Alessandro Montanari🇩🇪 · Oscar Macias🇺🇸 · Emmanuel Moulin🇫🇷

    The center of the Milky Way is a prime site to search for signals of dark matter (DM) annihilation due to its proximity and expected high concentration of DM. The amplification of the dispersion velocity of DM particles in the Galactic center (GC), caused by baryonic contraction and feedback, makes this particular region of the sky an even more promising target for exploring velocity-dependent DM models. Here we demonstrate that current GC observations with the H.E.S.S. telescope, presently the most sensitive TeV-scale gamma-ray telescope in operation in this region of the sky, set the strongest constraints on velocity-dependent annihilating DM particles with masses above 200 GeV. For p-wave annihilations, they improve the current constraints by a factor of $\sim$4 for a DM mass of 1 TeV. For the spatial distribution of DM, we use the results of the latest FIRE-2 zoom cosmological simulation of Milky Way-size halos. In addition, we utilize the newest version of the GALPROP cosmic-ray propagation framework to simulate the Galactic diffuse gamma-ray emission in the GC. We have found that p-wave (d-wave) DM particles with a mass of approximately 1.7 TeV and annihilating into the $W^{+}$$W^{-}$ channel exhibit a velocity-weighted annihilation cross-section upper limit of 4.6$\times$ 10${}^{-22}$ cm${}^3$s${}^{-1}$ (9.2$\times$10${}^{-17}$ cm${}^3$s${}^{-1}$) at a 95\% confidence level. This is about 460 (2$\times$ 10${}^6$) times greater than the thermal relic cross-section for p-wave (d-wave) DM models.

    ↳ astro-ph.HEastro-ph.COastro-ph.GAhep-phPRD(2023)·5 citations
38. 38*

    CMB constraints on inflection-point inflation with a pseudo-scalar dark matter

    Jamerson G. Rodrigues🇧🇷 · Vinícius Oliveira🇧🇷 · Rodrigo von Marttens🇧🇷 · Carlos A. de S. Pires🇧🇷 · Jailson Alcaniz🇧🇷

    In this work, we investigate the physical aspects of the inflection-point inflation scenario and assess its observational viability in light of current Cosmic Microwave Background (CMB) data. The model we consider encapsulates the inflaton with a pseudo-scalar (the dark matter candidate) in a complex neutral scalar singlet. The cosmological constraints on the parameters of inflation derived at a high energy scale are translated to a low energy scale by running these parameters. Ensuring the entire Lagrangian to be invariant under a $Z_3$ symmetry with the adequate transformation of the fields, the imaginary part of the singlet decouples from the other scalars of the model. We then investigate if the observational viability of inflation is also compatible with this pseudo-scalar being the dark matter component.We show that the CMB constraints on the inflationary parameters assure that the pseudo-scalar is stable and provides the correct relic dark matter abundance only when the pseudo-scalar is thermally produced.

    ↳ astro-ph.COhep-phPRD(2024)·2 citations
39. 39*

    Thorne-Żytkow objects with mirror neutron star cores?

    Z.K. Silagadze🇷🇺

    A Thorne-Żytkow object can be formed when a neutron star is absorbed by the envelope of its giant companion star, spirals toward the center of the giant star due to the drag from the surrounding envelope, and merges with the star's core. During in-spiral, dynamical friction is the main drag force acting on a neutron star inside the star envelope. However, dynamical friction is caused by the neutron star's gravitational interaction with its own gravitationally induced wake. Therefore, exactly the same gravitational drag force will act on a mirror neutron star, and if a significant part of the dark matter is in the form of mirror matter, then we expect the formation of Thorne-Żytkow objects with a mirror neutron star inside. We explore the plausibility of the existence of such exotic Thorne-Żytkow objects.

    ↳ astro-ph.HEgr-qchep-phMod.Phys.Lett.A(2024)·1 citation

* 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.