Fri·Apr 21, 2023Friday·April 21, 2023

1. 01*

   Gluon distributions in the proton in a light-front spectator model

   Dipankar Chakrabarti🇮🇳 · Poonam Choudhary🇮🇳 · Bheemsehan Gurjar🇮🇳 · Raj Kishore🇮🇳 · Tanmay Maji🇮🇳 · Chandan Mondal🇨🇳 · Asmita Mukherjee🇮🇳

   We formulate a light-front spectator model for the proton incorporating the gluonic degree of freedom. In this model, at high energy scattering of the proton, the active parton is a gluon and the rest is viewed as a spin-$\frac{1}{2}$ spectator with an effective mass. The light front wave functions of the proton are constructed using a soft wall AdS/QCD prediction and parameterized by fitting the unpolarized gluon distribution function to the NNPDF3.0nlo data set. We investigate the helicity distribution of gluon in this model. We find that our prediction for the gluon helicity asymmetry agrees well with existing experimental data and satisfies the perturbative QCD constraints at small and large longitudinal momentum regions. We also present the transverse momentum dependent distributions (TMDs) for gluon in this model. We further show that the model-independent Mulders-Rodrigues inequalities are obeyed by the TMDs computed in our model.

   hep-phPRD(2023)·39 citations
2. 02*

   Fully charmed resonance $X(6900)$ and its beauty counterpart

   S. S. Agaev🇦🇿 · K. Azizi🇮🇷 · B. Barsbay🇹🇷 · H. Sundu🇹🇷

   The fully heavy scalar tetraquarks $T_{4Q}=QQ\overline{Q}\overline{Q}$, ($Q=c,b$) are explored in the context of QCD sum rule method. We model $T_{4Q}$ as diquark-antidiquark systems composed of pseudoscalar constituents, and calculate their masses $m^{(\prime )}$ and couplings $f^{(\prime )}$ within the two-point sum rule approach. Our results $m=(6928\pm 50)\mathrm{MeV}$ and $m^{\prime }=(18858\pm 50)\mathrm{MeV}$ for masses of the tetraquarks $T_{4c}$ and $T_{4b}$ prove that they can decay to hidden-flavor heavy mesons. The full width ${\Gamma }_{4c}$ of the $T_{4c}$ is evaluated by taking into account the decay channels $T_{4c}\to J/\psi J/\psi$, $J/\psi {\psi }^{\prime }$, ${\eta }_c{\eta }_c$, ${\eta }_c{\eta }_c(2S)$, ${\eta }_c{\chi }_{c1}(1P)$, and ${\chi }_{c0}{\chi }_{c0}$. The partial widths of these processes depend on strong couplings $g_i$ at vertices $T_{4c}J/\psi J/\psi$, $T_{4c}J/\psi {\psi }^{\prime }$ etc., which are computed using the QCD three-point sum rule method. The decay $T_{4b}\to {\eta }_b{\eta }_b$ is used to find the width ${\Gamma }_{4b}$ of the $T_{4b}$. The predictions for $m$ and ${\Gamma }_{4c}=(128\pm 22)\mathrm{MeV}$ are compared with parameters of the fully charmed resonances reported by the LHCb, ATLAS, and CMS Collaborations. Based on this analysis, we interpret the tetraquark $T_{4c}$ as a candidate to the resonance $X(6900)$. The mass $m^{\prime }$ and width ${\Gamma }_{4b}=(94\pm 28)\mathrm{MeV}$ of the exotic meson $T_{4b}$ can be used in future experimental investigations of these

   hep-phhep-exhep-latNPA(2024)·35 citations
3. 03*

   Heavy quarkonium states with baryonic chemical potential

   Siddhartha Solanki🇮🇳 · Manohar lal🇮🇳 · Vineet Kumar Agotiya🇮🇳

   In this work, we have studied the dissociation behavior of 1S and 2S states of quarkonium using quasi-particle approach where the Debye mass depends on baryonic chemical potential. The binding energies of the quarkonium states has been obtained by using quasi-particle Debye mass which further depends on temperature and baryonic chemical potential ({mu}_b). The effect of {mu}_b on the binding energies and the dissociation temperature have been also studied. The binding energy and dissociation temperature of heavy quarkonia decreases as {mu}_b increases. The effect of {mu}_b on the mass spectra of quarkonium states has been studied well.

   hep-phAdv.High Energy Phys.(2025)·0 citations
4. 04*

   Probing primordial black holes from a first order phase transition through pulsar timing and gravitational wave signals

   Jan Tristram Acuña🇹🇼 · Po-Yan Tseng🇹🇼

   In this work, we assess the sensitivity reach of pulsar timing array (PTA) measurements to probe pointlike primordial black holes (PBHs), with an extended mass distribution, which originate from collapsed Fermi balls that are formed through the aggregation of asymmetric U(1) dark fermions trapped within false vacuum bubbles during a dark first order phase transition (FOPT). The PBH formation scenario is mainly characterized by the dark asymmetry, strength of the FOPT, rate of FOPT, and the percolation temperature. Meanwhile, for PBH masses of interest lying within $10^{-10}{M}_{\odot }-10^2{M}_{\odot }$, the relevant signal for PTA measurements is the Doppler phase shift in the timing signal, due to the velocity change induced by transiting PBHs on pulsars. Taking the dark asymmetry parameter to be $10^{-4}$ and $10^{-5}$, we find that percolation temperatures within the 0.1-10 keV range, FOPT rates above $10^3$ times the Hubble parameter at percolation, and FOPT strengths within $10^{-6}-0.1$ can give rise to PBHs that can be probed by an SKA-like PTA observation. On the other hand, the accompanying gravitational wave (GW) signal from the FOPT can be used as a complementary probe, assuming that the peak frequency lies within the $\mathcal{O}(10^{-10})-\mathcal{O}(10^{-7})$ Hz range, and the peak GW abundance is above the peak-integrated sensitivity curves associated with pulsar timing observations that search for stochastic GWs. At the fundamental level, a quartic effective potential for a dark scalar field can trigger the FOPT. By performing a parameter scan, we obtained the class of effective potentials that lead to FOPT scenarios that can be probed by SKA through pulsar timing and GW observations.

   hep-phastro-ph.HEJHEP(2023)·8 citations
5. 05*

   Analyzing cancellation mechanism of the dark matter-quark scattering in a complex singlet extension of the Standard Model

   Gi-Chol Cho🇯🇵 · Chikako Idegawa🇯🇵

   We investigate a suppression mechanism of dark matter and quark scattering amplitudes in a complex singlet extension of the Standard Model. It has been pointed out that, in a some variant of the model, the scattering amplitudes cancel each other in the limit in which two mediator scalars degenerate in their masses. We study the origin of such the cancellation mechanism and show that the operators describing the Higgs-singlet scalar mixing play essential role. We derive sum rules for couplings in the general scalar potential of the model, which guarantee the cancellation of the scattering amplitudes in the tree and the 1-loop level.

   hep-phNPB(2023)·10 citations
6. 06*

   Dai-Freed anomaly in the standard model and topological inflation

   Masahiro Kawasaki🇯🇵 · Tsutomu T. Yanagida🇯🇵

   When we impose the discrete symmetry in the standard model we have Dai-Freed global anomalies. However, interestingly if we introduce three right-handed neutrinos we can have an anomaly-free discrete $Z_4$ gauge symmetry. This $Z_4$ symmetry should be spontaneously broken down to the $Z_2$ symmetry to generate the heavy Majorana masses for the right-handed neutrinos. We show that this symmetry breaking naturally generates topological inflation, which is consistent with the CMB observations at present and predicts a significant tensor mode with scalar-tensor ratio $r>0.03$. The right-handed neutrinos play an important role in reheating processes. The reheating temperature is as high as $\sim 10^8$GeV, and non-thermal leptogenesis successfully takes place.

   hep-phastro-ph.COhep-thJHEP(2023)·9 citations
7. 07*

   Particles and antiparticles

   Dezső Horváth🇭🇺 · Zoltán Trócsányi🇭🇺

   We review the concept of chirality and charge for particles and antiparticles. We point out that the commonly accepted equivalence of particles and antiparticles - with difference only in the opposite signs of their charges, which follows from the CPT invariance - is valid only for free non-chiral particles. We show that with the weak interaction turned on the equivalence of particles and antiparticles is violated. We also discuss that within the Standard Model even free neutrinos are exceptions, they can be produced only in chiral states. We conclude that in spite of a long history of antiparticles, interesting theoretical and experimental challenges remain in their complete understanding.

   hep-phhep-exMod.Phys.Lett.A(2023)·0 citations
8. 08*

   Exploring the axion potential and axion walls in dense quark matter

   Bonan Zhang🇨🇳 · David E. A. Castillo🇵🇱 · Ana G. Grunfeld🇦🇷 · Marco Ruggieri🇮🇹

   We study the potential of the Quantum Chromodynamics axion in hot and/or dense quark matter, within a Nambu-Jona-Lasinio-like model that includes the coupling of the axion to quarks. Differently from previous studies, we implement local electrical neutrality and $\beta -$equilibrium, which are relevant for the description of the quark matter in the core of compact stellar objects. Firstly we compute the effects of the chiral crossover on the axion mass and self-coupling. We find that the low energy properties of axion are very sensitive to the phase transition of Quantum Chromodynamics, in particular, when the bulk quark matter is close to criticality. Then, for the first time in the literature we compute the axion potential at finite quark chemical potential and study the axion domain walls in bulk quark matter. We find that the energy barrier between two adjacent vacuum states decrease in the chirally restored phase: this results in a lower surface tension of the walls. Finally, we comment on the possibility of production of walls in dense quark matter.

   hep-phnucl-thPRD(2023)·14 citations
9. 09*

   The effects of the widths on the one-loop electroweak corrections to the $pp\to WW$ process

   N. Bekheddouma Abdi🇩🇿 · R. Bouamrane🇩🇿 · K. Khelifa-Kerfa🇩🇿

   In this paper, we study the effects of the widths of unstable particles on the one-loop electroweak corrections for the $pp\to WW$ process at the TeV scale within the framework of the complex mass scheme. We also investigate, for this same process, the unitarity of the theory at high energies.

   hep-phAdv.High Energy Phys.(2023)·0 citations
10. 10*

    Statement from the American Linear Collider Committee to the P5 subpanel

    J.A. Bagger🇺🇸 · S. Belomestnykh🇺🇸 · P.C. Bhat🇺🇸 · J.E. Brau🇺🇸 · M. Demarteau🇺🇸 · D. Denisov🇺🇸 · S. Gori🇺🇸 · P.D. Grannis🇺🇸 · T. Junginger🇨🇦 · A.J. Lankford🇺🇸 · M. Liepe🇺🇸 · T.W. Markiewicz🇺🇸 and 6 other authors

    This statement from the American Linear Collider Committee to the P5 subpanel has three purposes. It presents a brief summary of the case for an $e^{+}{e}^{-}$ Higgs factory that has emerged from Snowmass 2021. It highlights the special virtues of the ILC that are shared with other linear colliders but not with circular colliders. Finally, it calls attention to the resources available in the ILC White Paper for Snowmass (arXiv:2203.07622). The ALCC urges P5 to move the Higgs factory forward as a global project by assigning the idea of an $e^{+}{e}^{-}$ Higgs factory high priority, initiating a global discussion of the technology choice and cost sharing, and offering the option of siting the Higgs factory in the U.S.

    hep-phhep-ex0 citations
11. 11*

    Energy-momentum tensor in the scalar diquark model

    Arturo Amor-Quiroz🇫🇷 · William Focillon🇫🇷 · Cédric Lorcé🇫🇷 · Simone Rodini🇫🇷

    We compute all the gravitational form factors in the scalar diquark model at the one-loop level using two different regularization methods. We check explicitly that all the Poincaré sum rules are satisfied and we discuss in detail the results for the trace of the energy-momentum tensor. Finally we discuss the spatial distributions of energy and pressure in two and three dimensions.

    hep-phEPJC(2023)·16 citations
12. 12*

    Analytic Evolution of DGLAP Equations

    Matthew Markovych🇺🇸 · Asli Tandogan🇺🇸

    We present an analytical method to solve the leading order (LO) Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) evolution equations, which describe how parton distribution functions (PDFs) vary through different energy scales. Our approach utilizes the analytical technique that was previously employed to address the evolution of singular distribution amplitudes. The method is straightforward, mathematically transparent, and requires very little computational power. The approach involves assuming that the PDF can be expanded into a series of terms, which follow a recursion relation that we derive. To demonstrate the efficacy of our method, we utilize a toy model of PDF at initial scale. We initiate with a reasonable approximation of the experimentally calculated PDF and demonstrate that our approach yields the asymptotic behavior of the PDF.

    hep-ph2 citations
13. 13*

    Flavour and Higgs physics in $Z_2$-symmetric 2HD models near the decoupling limit

    Arturo de Giorgi🇪🇸 · Fotis Koutroulis🇵🇱 · Luca Merlo🇪🇸 · Stefan Pokorski🇵🇱

    With no evidence of any exotic particle detected so far beyond the Standard Model, the new physics may lie above the presently accessible energies at colliders and, at low-energies, can be accounted for via an effective description. The interplay of flavour and Higgs physics data allows setting stringent bounds on the parameters of the effective Lagrangian. In this paper, we focus on $Z_2$-symmetric two Higgs doublet models near the decoupling limit: the corresponding effective description relies on only a few parameters, thus predicting many interesting correlations between observables that work as tests of the theory. We present the results of a global fit to the existing data, updating and extending over the past literature. We comment on the triple Higgs coupling as a probe of an extended scalar sector and on the recent CDF II measurement of the $W$-mass.

    hep-phNPB(2023)·12 citations
14. 14*

    Vector-like Singlet Quarks: a Roadmap

    João M. Alves🇵🇹 · G. C. Branco🇵🇹 · A. L. Cherchiglia🇧🇷 · C. C. Nishi🇧🇷 · J. T. Penedo🇵🇹 · Pedro M. F. Pereira🇵🇹 · M. N. Rebelo🇵🇹 · J. I. Silva-Marcos🇵🇹

    We review the theory and phenomenology of isosinglet vector-like quarks (VLQs). In recent years, interest in VLQs has been increasing, due to their contributions to new physics effects that can be tested in experiments at LHC and High-Luminosity LHC. The similarities of models with isosinglet VLQs and the seesaw framework in the leptonic sector are pointed out. The existence of VLQs leads to flavour-changing neutral currents at tree level and deviations from unitarity of the CKM matrix, introducing rich phenomenological implications. These new effects are naturally suppressed by the masses of the new quarks, that are constrained to be above the electroweak scale. In addition, striking new effects can be achieved with the inclusion of an extra complex scalar singlet. Such a minimal extension of the SM can give rise to new sources of CP violation with profound theoretical implications, allowing for a solution to the strong CP problem and a possible explanation for the baryon asymmetry of the Universe. We list and explain strong motivations to consider this class of models. We also briefly review how models with VLQs can be matched to the SM effective field theory (SMEFT). A detailed analysis of flavour observables that can be affected by the presence of VLQs is presented. Current bounds from collider searches of VLQs are summarized. We point out that the discovery of VLQs can be within the reach of present or future colliders being planned.

    hep-phPhys.Rept.(2024)·90 citations
15. 15*

    Violation of the Landau-Yang theorem from Infrared Lorentz Symmetry Breaking

    M. Asorey🇪🇸 · A. P. Balachandran🇺🇸 · Arshad Momen🇧🇩 · B. Qureshi🇵🇰

    Lorentz symmetry forbids decays of massive spin-1 particle like the $Z^0$ into two massless photons, a result known as the Landau-Yang theorem. But it is known that infrared effects can break Lorentz invariance. Employing the construction of Mund et. al. \cite{MRS} which incorporated this Lorentz violation, we propose an interaction leading to the decay $Z^0\to 2\gamma$ and study the dependence of the decay on the parameter of this Lorentz violation.

    hep-phhep-thJHEP(2023)·5 citations
16. 16*

    Black holes in a new gravitational theory with trace anomalies

    Shinji Tsujikawa🇯🇵

    In a new gravitational theory with the trace anomaly recently proposed by Gabadadze, we study the existence of hairy black hole solutions on a static and spherically symmetric background. In this theory, the effective 4-dimensional action contains a kinetic term of the conformal scalar field related to a new scale $barM$ much below the Planck mass. This property can overcome a strong coupling problem known to be present in general relativity supplemented by the trace anomaly as well as in 4-dimensional Einstein-Gauss-Bonnet gravity. We find a new hairy black hole solution arising from the Gauss-Bonnet trace anomaly, which satisfies regular boundary conditions of the conformal scalar and metric on the horizon. Unlike unstable exact black hole solutions with a divergent derivative of the scalar on the horizon derived for some related theories in the literature, we show that our hairy black hole solution can be consistent with all the linear stability conditions of odd- and even-parity perturbations.

    ↳ gr-qchep-phhep-thPLB(2023)·9 citations
17. 17*

    Holography in anomaly flow in orbifold gauge theory

    Yutaka Hosotani🇯🇵

    In orbifold gauge theory and gauge-Higgs unification models, gauge anomaly flows with an Aharonov-Bohm phase ${\theta }_H$ in the fifth dimension. We analyze $SU(2)$ gauge theory with doublet fermions in the flat $M^4\times (S^1/Z_2)$ spacetime and in the Randall-Sundrum (RS) warped space. With orbifold boundary conditions the $U(1)$ part of gauge symmetry remains unbroken at ${\theta }_H=0$ and $\pi$. Chiral anomalies smoothly vary with ${\theta }_H$ in the RS space. Anomaly coefficients associated with this anomaly flow are expressed in terms of the values of the wave functions of gauge fields at the UV and IR branes in the RS space and parity conditions of fermion fields. Holography in anomaly flow is observed. Conditions for the anomaly cancellation turn out independent of ${\theta }_H$.

    ↳ hep-thhep-phPoS(2023)·0 citations
18. 18*

    No evidence for p- or d-wave dark matter annihilation from local large-scale structure

    Andrija Kostić🇩🇪 · Deaglan J. Bartlett🇫🇷 · Harry Desmond🇬🇧

    If dark matter annihilates into standard model particles with a cross-section which is velocity dependent, then Local Group dwarf galaxies will not be the best place to search for the resulting gamma ray emission. A greater flux would be produced by more distant and massive halos, with larger velocity dispersions. We construct full-sky predictions for the gamma-ray emission from galaxy- and cluster-mass halos within $\sim 200\mathrm{Mpc}$ using a suite of constrained $N$-body simulations ($\text{CSiBORG}$) based on the Bayesian Origin Reconstruction from Galaxies algorithm. Comparing to observations from the Fermi Large Area Telescope and marginalising over reconstruction uncertainties and other astrophysical contributions to the flux, we obtain constraints on the cross-section which are two (seven) orders of magnitude tighter than those obtained from dwarf spheroidals for $p$-wave ($d$-wave) annihilation. We find no evidence for either type of annihilation from dark matter particles with masses in the range $m_{\chi }=2-500\mathrm{GeV}/c^2$, for any channel. As an example, for annihilations producing bottom quarks with $m_{\chi }=10\mathrm{GeV}/c^2$, we find $a_1<2.4\times 10^{-21}\mathrm{c}{\mathrm{m}}^3{\mathrm{s}}^{-1}$ and $a_2<3.0\times 10^{-18}\mathrm{c}{\mathrm{m}}^3{\mathrm{s}}^{-1}$ at 95% confidence, where the product of the cross-section, $\sigma$, and relative particle velocity, $v$, is given by $\sigma v=a_{\ell }(v/c{)}^{2\ell }$ and $\ell =1,2$ for $p$-, $d$-wave annihilation, respectively. Our bounds, although failing to exclude the thermal relic cross-section for velocity-dependent annihilation channels, are among the tightest to date.

    ↳ astro-ph.COastro-ph.GAastro-ph.HEhep-phPRD(2026)·11 citations
19. 19*

    Towards a Benchmark for Scientific Understanding in Humans and Machines

    Kristian Gonzalez Barman🇧🇪 · Sascha Caron🇳🇱 · Tom Claassen · Henk de Regt🇳🇱

    Scientific understanding is a fundamental goal of science, allowing us to explain the world. There is currently no good way to measure the scientific understanding of agents, whether these be humans or Artificial Intelligence systems. Without a clear benchmark, it is challenging to evaluate and compare different levels of and approaches to scientific understanding. In this Roadmap, we propose a framework to create a benchmark for scientific understanding, utilizing tools from philosophy of science. We adopt a behavioral notion according to which genuine understanding should be recognized as an ability to perform certain tasks. We extend this notion by considering a set of questions that can gauge different levels of scientific understanding, covering information retrieval, the capability to arrange information to produce an explanation, and the ability to infer how things would be different under different circumstances. The Scientific Understanding Benchmark (SUB), which is formed by a set of these tests, allows for the evaluation and comparison of different approaches. Benchmarking plays a crucial role in establishing trust, ensuring quality control, and providing a basis for performance evaluation. By aligning machine and human scientific understanding we can improve their utility, ultimately advancing scientific understanding and helping to discover new insights within machines.

    ↳ cs.AIcs.CLcs.HChep-ph+1Minds Machines(2024)·2 citations
20. 20*

    Nuclear T-violation search using octupole-deformed nuclei in a crystal

    Harish D. Ramachandran🇨🇦 · Amar C. Vutha🇨🇦

    Precision measurements with atoms and molecules can search for subtle violations of time-reversal symmetry (T) in nuclei, and thereby probe a variety of new physics models. We present a detailed scheme for a nuclear T-violation search experiment using ${}^{153}$Eu${}^{3+}$ ions doped in non-centrosymmetric sites within a Y${}_2$SiO${}_5$ crystal. The ions in this solid contain nuclei that are highly sensitive to T-violation, and avail of large atomic enhancements by being polarized within the solid. But in particular, the system and methods that we discuss here enable the use of vast numbers of nuclei trapped in crystals, while also offering a number of stringent tests to ward off systematic errors. Our approach maps out a path to probe new physics at the PeV energy scale.

    ↳ physics.atom-phhep-exhep-phPRA(2023)·11 citations
21. 21*

    Synchronizing the Consistency Relation

    Keisuke Inomata🇺🇸 · Hayden Lee🇺🇸 · Wayne Hu🇺🇸

    We study the $N$-point function of the density contrast to quadratic order in the squeezed limit during the matter-dominated (MD) and radiation-dominated (RD) eras in synchronous gauge. Since synchronous gauge follows the free-fall frame of observers, the equivalence principle dictates that in the gradient approximation for the long-wavelength mode there is only a single, manifestly time-independent consistency relation for the $N$-point function. This simple form is dictated by the initial mapping between synchronous and local coordinates, unlike Newtonian gauge and its correspondingly separate dilation and Newtonian consistency relations. Dynamical effects only appear at quadratic order in the squeezed limit and are again characterized by a change in the local background, also known as the separate universe approach. We show that for the 3-point function the compatibility between these squeezed-limit relations and second-order perturbation theory requires both the initial and dynamical contributions to match, as they do in single-field inflation. This clarifies the role of evolution or late-time projection effects in establishing the consistency relation for observable bispectra, which is especially important for radiation acoustic oscillations and for establishing consistency below the matter-radiation equality scale in the MD era. Defining an appropriate angle and time average of these oscillations is also important for making separate universe predictions of spatially varying local observables during the RD era, which can be useful for a wider range of cosmological predictions beyond $N$-point functions.

    ↳ astro-ph.COgr-qchep-phhep-thJCAP(2023)·6 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.