Mon·Apr 8, 2024Monday·April 8, 2024

1. 01*

   Study of the axial-vector and tensor resonant contributions to the $D\to VP{\ell }^{+}{\nu }_{\ell }$ decays based on SU(3) flavor analysis

   Yi Qiao🇨🇳 · Yue-Xin Liu🇨🇳 · Yuan-Guo Xu🇨🇳 · Ru-Min Wang🇨🇳

   Semileptonic three-body $D\to M{\ell }^{+}{\nu }_{\ell }$ decays, non-leptonic $M\to VP$ decays, and semileptonic four-body $D\to M(M\to VP){\ell }^{+}{\nu }_{\ell }$ decays are analyzed using the SU(3) flavor symmetry/breaking approach, where $\ell =e/\mu$, $M=A/T$, and $A/T/V/P$ denote the axial-vector/tensor/vector/pseudoscalar mesons, respectively. In terms of SU(3) flavor symmetry/breaking, the decay amplitudes of the $D\to M{\ell }^{+}{\nu }_{\ell }$ decays and the vertex coefficients of the $M\to VP$ decays are related. The relevant non-perturbative parameters of the $D\to A{\ell }^{+}{\nu }_{\ell }$, $A\to VP$ and $T\to VP$ decays are constrained by the present experimental data, and the non-perturbative parameters of $D\to T{\ell }^{+}{\nu }_{\ell }$ decays are taken from the results in the light-front quark model since no experimental data are available at present. The branching ratios of the $D\to M{\ell }^{+}{\nu }_{\ell }$, $M\to VP$, and $D\to M(M\to VP){\ell }^{+}{\nu }_{\ell }$ decays are then predicted. We find that some processes receive both tensor and axial-vector resonant contributions, while other processes receive only axial-vector resonant contributions. In cases where both kinds of resonant contributions exist, the axial-vector contributions are dominant. Some branching ratios with axial-vector resonance states are large, and they may be measured experimentally in the near future. In addition, the sensitivities of the branching ratios of $D\to A{\ell }^{+}{\nu }_{\ell }$ and $A\to VP$ decays to the parameters are also investigated, and some decay branching ratios are found to be sensitive to the non-perturbative parameters.

   hep-phEPJC(2024)·9 citations
2. 02*

   Photo-production of ${\eta }_{c,b}$ near Threshold

   Wei-Yang Liu🇺🇸 · Ismail Zahed🇺🇸

   We analyze the photo-production of ${\eta }_{c,b}$ off a proton in the threshold region, in terms of C-odd gluonic correlations in the off-forward proton matrix element. Near threshold, the skewness is large leading to a production amplitude that is dominated by four C-odd twist-3 gluon GPDs. We use the QCD instanton vacuum to estimate these C-odd contributions in the proton. The results are used to estimate the differential cross sections for coherent photo-production of ${\eta }_{c,b}$ in the threshold region, at current electron facilities.

   hep-phnucl-thPRD(2024)·9 citations
3. 03*

   Poles and Poltergeists in $e^{+}{e}^{-}\to D\bar{D}$ Data

   Nils Hüsken🇩🇪 · Richard F. Lebed🇺🇸 · Ryan E. Mitchell🇺🇸 · Eric S. Swanson🇺🇸 · Ya-Qian Wang🇨🇳 · Chang-Zheng Yuan🇨🇳

   A recent report of $e^{+}{e}^{-}\to D\bar{D}$ events by the BESIII Collaboration suggests the presence of a structure $R$ at 3900~MeV\@. We argue that this structure, called $G(3900)$ in the past, is not in fact due to a new $c\bar{c}$ resonance, but rather naturally emerges as a threshold enhancement due to the opening of the $D^{\ast }\bar{D}$ channel. We further find that the appearance of this structure does not require suppression because of a radial node in the $\psi (4040)$ wave function, although a node improves fit quality. The measured $e^{+}{e}^{-}$ coupling of $\psi (4040)$ is found to be substantially smaller than previously estimated. In addition, we report new corrections to the measured cross section $\sigma (e^{+}{e}^{-}\to D\bar{D})$ at energies near $\psi (3770)$.

   hep-phPRD(2024)·27 citations
4. 04*

   Summary of Working Group 4: Mixing and mixing-related $CP$ violation in the B system: $\Delta m$, $\Delta \Gamma$, ${\varphi }_s$, ${\varphi }_1/\alpha$, ${\varphi }_2/\beta$, ${\varphi }_3/\gamma$

   Agnieszka Dziurda🇵🇱 · Felix Erben🇨🇭 · Marc Quentin Führing🇩🇪 · Thibaud Humair🇩🇪 · Thomas Latham🇬🇧 · Eleftheria Malami🇳🇱 · Pascal Reeck🇩🇪 · Vladyslav Shtabovenko🇩🇪 · Melissa Cruz Torres🇧🇷 · Yuma Uematsu · K. Keri Vos🇳🇱

   This summary reviews contributions to the CKM 2023 workshop in Working Group 4: mixing and mixing-related $CP$ violation in B system. The theoretical and experimental progress is discussed.

   hep-phhep-ex5 citations
5. 05*

   Composite Dark Matter with Forbidden Annihilation

   Tomohiro Abe🇯🇵 · Ryosuke Sato🇯🇵 · Takumu Yamanaka🇯🇵

   A dark matter model based on QCD-like $SU(N_c)$ gauge theory with electroweakly interacting dark quarks is discussed. Assuming the dark quark mass $m$ is smaller than the dynamical scale ${\Lambda }_d\sim 4\pi f_d$, the main component of the dark matter is the lightest $G$-parity odd dark pion associated with chiral symmetry breaking in the dark sector. We show that nonzero dark quark mass induces the universal mass contribution to both $G$-parity odd and even pions, and their masses tend to be degenerate. As a result, dark pion annihilation into heavier $G$-parity even dark pion also affects the dark matter relic abundance. Thus, our setup naturally accommodates forbidden dark matter scenario and realizes heavy dark matter whose mass is $\mathcal{O}(1$-$100)\mathrm{TeV}$, which is different from conventional electroweakly interacting dark matter such as minimal dark matter. We also discuss CP-violation from $\theta$-term in the dark gauge sector and find that the predicted size of electron electric dipole moment can be as large as $\sim 10^{-32}e\mathrm{cm}$.

   hep-phastro-ph.COJHEP(2024)·16 citations
6. 06*

   Flavor-spin symmetry of the $P_{\psi }^N/H_{{\Omega }_{ccc}}^N$ and $P_{\psi s}^{\Lambda }/H_{{\Omega }_{ccc}s}^{\Lambda }$ molecular states

   Kan Chen🇨🇳 · Bo Wang🇨🇳

   Based on a contact lagrangian that incorporates the SU(3) flavor and SU(2) spin symmetries, we discuss the symmetry properties of the interactions among the heavy flavor meson-baryon $P_{\psi }^N$, $P_{\psi s}^{\Lambda }$ (with quark components [$n\bar{c}$][$nnc$], [$s\bar{c}$][$nnc$], or [$n\bar{c}$][$nsc$]) systems and di-baryon $H_{{\Omega }_{ccc}}^N$, $H_{{\Omega }_{ccc}s}^{\Lambda }$ (with quark components [$nnc$][$ncc$], [$nnc$][$scc$] or [$nsc$][$ncc$]) systems ($n=u$, $d$). The light quark components of the $P_{\psi }^N$ ($P_{\psi s}^{\Lambda }$) and $H_{{\Omega }_{ccc}}^N$ ($H_{{\Omega }_{ccc}s}^{\Lambda }$) systems have identical flavors, the interactions generated from the exchanges of light mesons in the $P_{\psi }^N$ ($P_{\psi s}^{\Lambda }$) systems should be very similar to that of the $H_{{\Omega }_{ccc}}^N$ ($H_{{\Omega }_{ccc}s}^{\Lambda }$) systems. We perform the single-channel and multi-channel calculations on the $P_{\psi }^N/P_{\psi s}^{\Lambda }/H_{{\Omega }_{ccc}}^N/H_{{\Omega }_{ccc}s}^{\Lambda }$ systems and introduce the SU(3) breaking effect to identify the different mass spectra among the $P_{\psi }^N$ ($H_{{\Omega }_{ccc}}^N$) and $P_{\psi s}^{\Lambda }$ ($H_{{\Omega }_{ccc}s}^{\Lambda }$) systems. We suggest two kinds of evidences for the existence of the flavor-spin symmetry among the heavy flavor $P_{\psi }^N/H_{{\Omega }_{ccc}}^N/P_{\psi s}^{\Lambda }/H_{{\Omega }_{ccc}s}^{\Lambda }$ molecule community, i.e., the mass arrangements of the $P_{\psi }^N/H_{{\Omega }_{ccc}}^N/P_{\psi s}^{\Lambda }/H_{{\Omega }_{ccc}s}^{\Lambda }$ mass spectra and the binding energies of the heavy flavor meson-baryon (di-baryon) systems attributed to the same contact potentials.

   hep-phhep-exPRD(2024)·4 citations
7. 07*

   Vacuum correlations of the stress-energy-momentum tensor with constituent quarks

   Mirko Serino · Wojciech Broniowski🇵🇱 · Enrique Ruiz Arriola🇪🇸

   The two point correlation function of the stress-energy-momentum tensor describes the propagation of a space-time "micro-earthquake" in the vacuum. In the framework of the path integral formulation of field theory in curved space-time, we derive the Ward-Takashi identity for two-point Green's function of the stress-energy-momentum tensor for a general case of a non-conformal theory. The identity constrains the longitudinal part of the correlator, with the vacuum expectation value of the stress-energy-momentum, non-zero in a non-conformal theory. The obtained formula is demonstrated on the free massive Dirac fermion theory, treated at the one-loop level. This example befits a class of phenomenological chiral quarks models which have been used successfully in numerous applications in the soft non-perturbative regime of strong interactions. We discuss the constraints following from the Ward-Takahashi identity for the correlation functions in these models. We also show how the temporal representation of the two-point correlators, which is an object amenable to lattice QCD, displays an expected exponential fall-off.

   hep-phhep-lathep-th0 citations
8. 08*

   Strangeness $+1$ light multiquark baryons

   Brenda B. Malabarba🇧🇷 · K. P. Khemchandani🇧🇷 · A. Martinez Torres🇧🇷 · Seung-il Nam🇰🇷

   In view of the renewing experimental interest for searching strangeness $+1$ baryons at J-PARC, we study the existence of light baryon resonances with strangeness +1 generated in the $K$-$(N^{\ast }/{\Delta }^{\ast })$ system, where $N^{\ast }$ represents either $N^{\ast }(1535)$/$N^{\ast }(1650)$/$N^{\ast }(1700)$, and ${\Delta }^{\ast }$ corresponds to $\Delta (1620)$. The description of the properties of the aforementioned states requires considering the dynamics involved in the coupled pseudoscalar-baryon and vector-baryon systems with strangeness $S=0$ in the s-wave. For the purpose of our current study, we consider the pseudoscalar-baryon (PB) and vector-baryon channels (VB) to which the mentioned $N^{\ast }$ and ${\Delta }^{\ast }$ resonances couple and solve the Faddeev equations for the coupled channel system $K$-$\text{PB}$, $K$-$\text{VB}$, with all interactions being in the s-wave. Despite some strong attraction present in two of the subsystems, we do not find clear evidence supporting the formation of strangeness +1 states, with spin-parity $J^P=1/2^{+}$, in the energy region $2000-2200$ MeV. However, the case of spin-parity $J^P=3/2^{+}$ seems more promising, showing the formation of a resonance with a mass around 2167 MeV, with a width of 90-100 MeV. We suggest that a signal of such a state could be found in processes with final states like $KN$, $K^{\ast }(892)N$.

   hep-phnucl-thPRD(2025)·8 citations
9. 09*

   Center-of-mass energy dependence of intrinsic-$k_T$ distributions obtained from Drell-Yan production

   I. Bubanja🇲🇪 · H. Jung🇩🇪 · A. Lelek🇧🇪 · N. Raicevic🇲🇪 · S. Taheri Monfared🇩🇪

   The internal motion of partons inside hadrons has been studied through its impact on very low transverse momentum spectra of Drell-Yan (DY) pairs created in hadron-hadron collisions. We study DY production at next-to-leading order using the Parton Branching (PB) method which describes the evolution of transverse momentum dependent parton distributions. The main focus is on studying the intrinsic transverse momentum distribution (intrinsic-$k_T$) as a function of the center-of-mass energy $\sqrt{s}$. While collinear parton shower Monte Carlo event generators require intrinsic transverse momentum distributions strongly dependent on $\sqrt{s}$, this is not the case for the PB method. We perform a detailed study of the impact of soft parton emissions. We show that by requiring a minimal transverse momentum, $q_0$, of a radiated parton, a dependence of the width of the intrinsic-$k_T$ distribution as a function of $\sqrt{s}$ is observed. This dependence becomes stronger with increasing $q_0$.

   hep-phhep-exEPJC(2025)·24 citations
10. 10*

    Quantum radiation reaction: Analytical approximations and obtaining the spectrum from moments

    Greger Torgrimsson🇸🇪

    We derive analytical $\chi \ll 1$ approximations for spin-dependent quantum radiation reaction for locally constant and locally monochromatic fields. We show how to factor out fast spin oscillations and obtain the degree of polarization in the plane orthogonal to the magnetic field from the Frobenius norm of the Mueller matrix. We show that spin effects lead to a transseries in $\chi$, with powers ${\chi }^k$, logarithms $(\ln \chi {)}^k$ and oscillating terms, $\cos (\dots /\chi )$ and $\sin (\dots /\chi )$. In our approach we can obtain each moment, $⟨(kP{)}^m⟩$, of the lightfront longitudinal momentum independently of the other moments and without considering the spectrum. We show how to obtain a low-energy expansion of the spectrum from the moments by treating $m$ as a continuous, complex parameter and performing an inverse Mellin transform. We also show how to obtain the spectrum, without making a low-energy approximation, from a handful of moments using the principle of maximum entropy.

    hep-phhep-thphysics.plasm-phPRD(2024)·3 citations
11. 11*

    Jet angularities in dijet production in proton-proton and heavy-ion collisions at RHIC

    Yang-Ting Chien🇺🇸 · Oleh Fedkevych🇺🇸 · Daniel Reichelt🇬🇧 · Steffen Schumann🇩🇪

    We study jet angularities for dijet production at the Relativistic Heavy Ion Collider (RHIC) in proton-proton (pp) and nucleus-nucleus (AA) collisions at 200 GeV nucleon-nucleon center-of-mass collision energy. In particular, we provide $\mathrm{NLL}$ resummed predictions for angularity observables of groomed and ungroomed jets produced in $\mathrm{pp}$ collisions matched to next-to-leading order QCD calculations resulting in $\mathrm{NLO}+\mathrm{NL}{\mathrm{L}}^{\prime }$ accuracy. Our parton-level predictions are corrected for non-perturbative effects, such as hadronization and underlying event, using parton-to-hadron level transfer matrices obtained with the Sherpa event generator. Furthermore, we use the Q-Pythia and JEWEL generators to estimate the impact of the interaction between quarks and gluons produced by the parton shower with the dense medium formed in heavy-ion collisions on the considered jet angularities.

    hep-phhep-exnucl-exnucl-thJHEP(2024)·18 citations
12. 12*

    Spin-orbit entanglement in the Color Glass Condensate

    Shohini Bhattacharya🇺🇸 · Renaud Boussarie🇫🇷 · Yoshitaka Hatta🇺🇸

    We compute the spin-orbit correlations of quarks and gluons at small-$x$ and show that the helicity and the orbital angular momentum of individual partons are strongly anti-aligned even in unpolarized or spinless hadrons and nuclei. Combined with the fact that gluons in the Color Glass Condensate are linearly polarized, our finding indicates that the helicity and the orbital angular momentum of single gluons are maximally entangled in a quantum mechanical sense.

    hep-phPLB(2024)·35 citations
13. 13*

    Exploring orbital angular momentum and spin-orbit correlation for gluons at the Electron-Ion Collider

    Shohini Bhattacharya🇺🇸 · Renaud Boussarie🇫🇷 · Yoshitaka Hatta🇺🇸

    In our previous work [Phys. Rev. Lett. 128, 182002 (2022)], we introduced a pioneering observable aimed at experimentally detecting the orbital angular momentum (OAM) of gluons. Our focus was on the longitudinal double spin asymmetry observed in exclusive dijet production during electron-proton scattering. We demonstrated the sensitivity of the $\cos \varphi$ angular correlation between the scattered electron and proton as a probe for gluon OAM at small-$x$ and its intricate interplay with gluon helicity. This current work provides a comprehensive exposition, diving further into the aforementioned calculation with added elaboration and in-depth analysis. We reveal that, in addition to the gluon OAM, one also gains access to the spin-orbit correlation of gluons. We supplement our work with a detailed numerical analysis of our observables for the kinematics of the Electron-Ion Collider. In addition to dijet production, we also consider the recently proposed semi-inclusive diffractive deep inelastic scattering process which potentially offers experimental advantages over dijet measurements. Finally, we investigate quark-channel contributions to these processes and find an unexpected breakdown of collinear factorization.

    hep-phhep-exPRD(2025)·29 citations
14. 14*

    Understanding the SM gauge group from SMEFT

    Hao-Lin Li🇧🇪 · Ling-Xiao Xu🇮🇹

    We discuss heavy particles that can be used to pin down the faithful Standard Model (SM) gauge group and their patterns in the SM effective field theory (SMEFT). These heavy particles are not invariant under a specific ${\mathbb{Z}}_6$ subgroup of $SU(3{)}_c\times SU(2{)}_L\times U(1{)}_Y$, which however acts trivially on all the SM particles, hence the faithful SM gauge group remains undetermined. Different realizations of the faithful SM gauge group correspond to different spectra of heavy particles, and they also correspond to distinct sets of line operators with one-form global symmetry acting on them. We show that the heavy particles not invariant under the ${\mathbb{Z}}_6$ group cannot appear in tree-level ultraviolet completions of SMEFT, this enforces us to consider one-loop UV completions of SMEFT to identify the ${\mathbb{Z}}_6$ non-invariant heavy particles. We demonstrate with examples that correlations between Wilson coefficients provide an efficient way to examine models with ${\mathbb{Z}}_6$ non-invariant heavy particles. Finally, we prove that all the scalars that can trigger electroweak symmetry breaking must be invariant under the ${\mathbb{Z}}_6$ group, hence they cannot be used to probe the faithful SM gauge group.

    hep-phhep-exhep-thJHEP(2024)·26 citations
15. 15*

    Light-by-light scattering in ultraperipheral collisions of heavy ions with future FoCal and ALICE 3 detectors

    Antoni Szczurek🇵🇱

    I present possible future studies of light-by-light scattering using FoCal@ALICE and ALICE 3 detectors. Different mechanisms are discussed. The PbPb$\to$PbPb$\gamma \gamma$ cross section is calculated within equivalent photon approximation in the impact parameter space. Several differential distributions are presented and discussed. We predict cross section in the (mb-b) range for typical ALICE 3 cuts, a few orders of magnitude larger than for the current ATLAS or CMS experiments. We also consider the two-${\pi }^0$ background which can, in principle, be eliminated at the new kinematical range for the ALICE 3 measurements by imposing dedicated cuts on diphoton transverse momentum and$\text{slash}$or so-called vector asymmetry.

    hep-phnucl-thPhys.Proc.UPC(2024)·0 citations
16. 16*

    Direct-collapse supermassive black holes from relic particle decay

    Yifan Lu🇺🇸 · Zachary S. C. Picker🇺🇸 · Alexander Kusenko🇺🇸

    We investigate the formation of high-redshift supermassive black holes (SMBHs) via the direct collapse of baryonic clouds, where the unwanted formation of molecular hydrogen is successfully suppressed by a Lyman-Werner (LW) photon background from relic particle decay. We improve on existing studies by dynamically simulating the collapse, accounting for the adiabatic contraction of the DM halo, as well as the in-situ production of the LW photons within the cloud which reduce the impact of the cloud's shielding. We find a viable parameter space where the decay of either some of the dark matter or all of a subdominant decaying species successfully allows direct collapse of the cloud to a SMBH.

    ↳ astro-ph.GAastro-ph.COhep-phPRL(2024)·24 citations
17. 17*

    Neutrinos as possible probes for quantum gravity

    Marco Danilo Claudio Torri🇮🇹 · Lino Miramonti🇮🇹

    In this paper, we aim to explore the interplay between neutrinos and quantum gravity, illustrating some proposals about the use of these particles as probes for the supposed quantized structure of spacetime. The residual signatures of a more fundamental theory of quantum gravity can manifest themselves modifying the free particle dispersion relations and the connected velocity. In neutrino sector these supposed effects can modify the time of flight for astrophysical particles with different energies and can affect the usual neutrino oscillation pattern introducing species depending perturbations. We will highlight how perturbations caused by non-standard interactions in the solar neutrino sector can mimic the presumed quantum gravity effects. In fact, the mathematical formulation of non-standard interactions is equivalent to that of CPT-odd perturbations. We will, therefore, emphasize the need to identify the nature of different contributions in order to disentangle them in the search for quantum gravity effects. As a final point we will discuss the possibility to detect in the neutrino sector decoherence effects caused by the quantum gravity supposed perturbations. By reviewing current experimental constraints and observations, we seek to shed light on the intricate relationship between neutrinos and quantum gravity, and discuss the challenges and future directions in this fascinating field of research.

    ↳ gr-qchep-phhep-thClass.Quant.Grav.(2024)·9 citations
18. 18*

    Quadratic Rastall Gravity: from low-mass HESS J1731-347 to high-mass PSR J0952-0607 pulsars

    Waleed El Hanafy🇪🇬

    Similar to Rastall gravity we introduce matter-geometry nonminimal coupling which is proportional to the gradient of quadratic curvature invariants. Those are mimicking the conformal trace anomaly when backreaction of the quantum fields to a curved spacetime geometry is considered. We consider a static spherically symmetric stellar structure with anisotropic fluid and Krori-Barua metric potentials model to examine the theory. Confronting the model with NICER+XMM-Newton observational constraints on the pulsar PSR J0740$+$6620 quantifies the amount of the nonminimal coupling via a dimensionless parameter $ϵ\simeq -0.01$. We verify that the conformal symmetry is broken everywhere inside the pulsar as the trace anomaly $\Delta >0$, or equivalently the trace of the stress-energy tensor $\mathfrak{T}<0$, whereas the adiabatic sound speed does not violate the conjecture conformal upper limit $v_r^2/c^2=1/3$. The maximum compactness accordingly is $C_{\text{max}}=0.752$ which is $4\%$ higher than GR. Notably, if the conformal sound speed constraint is hold, observational data excludes $ϵ\ge 0$ up to $\ge 1.6\sigma$. The stellar model is consistent with the self-bound structure with soft linear equation of state. Investigating possible connection with MIT bag model of strange quarks sets physical bounds from microscopic physics which confirm the negative value of the parameter $ϵ$. We estimate a radius $R=13.21\pm 0.96$ km of the most massive observed compact star PSR J0952$-$0607 with $M=2.35\pm 0.17M_{\odot }$. Finally, we show that the corresponding mass-radius diagram fits well lowest-mass pulsar HESS J1731$-$347 and highest-mass pulsar PSR J0952$-$0607 ever observed as well as the intermediate mass range as obtained by NICER and LIGO/Virgo observations.

    ↳ astro-ph.HEgr-qchep-phEPJC(2024)·17 citations
19. 19*

    Relativistic head-on collisions of $U(1)$ gauged Q-balls

    Michael P. Kinach🇨🇦 · Matthew W. Choptuik🇨🇦

    We investigate the collision dynamics of $U(1)$ gauged Q-balls by performing high-resolution numerical simulations in axisymmetry. Focusing on the case of relativistic head-on collisions, we consider the effects of the initial velocity, relative phase, relative charge, and electromagnetic coupling strength on the outcome of the collision. We find that the collision dynamics can depend strongly on these parameters; most notably, electromagnetic effects can significantly alter the outcome of the collision when the gauge coupling is large. When the gauge coupling is small, we find that the dynamics generally resemble those of ordinary (non-gauged) Q-balls.

    ↳ hep-thgr-qchep-phPRD(2024)·7 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.