Tue·Dec 6, 2022Tuesday·December 6, 2022

1. 01*

   Search for pair production of the heavy vectorlike top partner in same-sign dilepton signature at the HL-LHC

   Xiao-Min Cui🇨🇳 · Yu-Qi Li🇨🇳 · Yao-Bei Liu🇨🇳

   New vectorlike quarks are predicted in many new physics scenarios beyond the Standard Model~(SM) and could potentially be discovered at the LHC. Based on a simplified model including a singlet vectorlike top partner with charge $2/3$, we investigate the process $pp\to TT$ via a $t$-channel induced by the couplings between the top partner with the first-generation SM quarks. We calculate the production cross section and further study the observability of the heavy top partner in the channel $T\to Wq$ at the high-luminosity LHC (HL-LHC) using final states with same-sign dileptons (electrons or muons), two jets, and missing transverse momentum. At the 14 TeV LHC with an integrated luminosity of 3000 fb${}^{-1}$, the $2\sigma$ exclusion limits, as well as the $5\sigma$ discovery reach in the parameter plane of the two variables $g^{\ast }-R_L$, are respectively obtained at the HL-LHC. We also obtain the $2\sigma$ exclusion limit on the coupling strength parameter $g^{\ast }$ in the case in which the vectorlike top partner is coupled only to the first-generation quarks.

   hep-phPRD(2022)·19 citations
2. 02*

   New physics contributions to $Wtb$ anomalous couplings and top-quark decay

   Apurba Tiwari🇮🇳 · Sudhir Kumar Gupta🇮🇳

   In this work, we study the new physics effects arising due the presence of anomalous $Wtb$ vertex through the semileptonic decay modes of the top-quark at the Large Hadron Collider. An estimate on the sensitivities of the aforementioned interaction at 5$\sigma$ CL in the context of top-quark decay-width measurements and cross-section measurements would also be discussed for the pre-existing 13 TeV LHC data and its projections for the proposed LHC runs at 14 TeV, 27 TeV and 100 TeV. We also incorporate the $\mathcal{C}P$-violating effects to such interactions by constructing the $\mathcal{C}P$-violating asymmetries.

   hep-phhep-exPoS(2022)·0 citations
3. 03*

   Gravitational Coleman-Weinberg Mechanism

   Clara Álvarez-Luna🇪🇸 · Sergio de la Calle-Leal🇪🇸 · José A. R. Cembranos🇪🇸 · Juan José Sanz-Cillero🇪🇸

   The Coleman-Weinberg mechanism provides a procedure by which a scalar field, which initially has no mass parameters, acquires a mass due to the anomalous nature of scale symmetry. Loop corrections trigger a spontaneous symmetry breaking and the appearance of a non-trivial vacuum. We first review the basic example of the ColemanWeinberg mechanism, scalar Quantum Electrodynamics, in a perturbative regime where the scalar particle becomes massive through photon loops. We then present the main results of this article, what we name the gravitational Coleman-Weinberg mechanism: we analyse the same effect in a gravitational theory without explicit energy scales at tree-level. Finally, we also study the mechanism for two scalar fields in the mentioned gravitational theory. We will derive the gravitational Coleman-Weinberg potentials, analyse the parameter space where we have a symmetry breaking, and obtain the value of the corresponding scalar masses.

   hep-phJHEP(2023)·14 citations
4. 04*

   The Higgs impact factor at next-to-leading order

   Michael Fucilla🇮🇹

   We compute at next-to-leading order level the impact factor for the production of a forward Higgs boson from a colliding proton. Combined with other forward impact factors, it can be used to describe, at next-to-leading logarithmic accuracy, processes in which two objects featuring large separation in rapidity are detected at the Large Hadron Collider (LHC). As well, combined with a proper definition of the \textit{unintegrated gluon distribution} (UGD), it can be used to compute small-$x$ corrections to the forward Higgs production.

   hep-phhep-exActa Phys.Polon.Supp.(2023)·10 citations
5. 05*

   Study of CP Violation in $D^{\pm }\to K^{\ast }(892{)}^0{\pi }^{\pm }+{\bar{K}}^{\ast }(892{)}^0{\pi }^{\pm }\to K_{S,L}^0{\pi }^0{\pi }^{\pm }$ Decays

   Ru-Min Wang🇨🇳 · Xiao-Dong Cheng🇨🇳 · Xing-Bo Yuan🇨🇳

   Within the Standard Model, we investigate the CP violations and the $K_S^0-K_L^0$ asymmetries in $D^{\pm }\to K^{\ast }(892{)}^0{\pi }^{\pm }+{\bar{K}}^{\ast }(892{)}^0{\pi }^{\pm }\to K_{S,L}^0{\pi }^0{\pi }^{\pm }$ decays basing on the factorization-assisted topological-amplitude (FAT) approach and the topological amplitude (TA) approach of Cheng and Chiang [Phys. Rev. D 104, 073003 (2021).]. We find that the CP violations in these decays $A_{CP}^{K_{S,L}^0}$ can exceed the order of $10^{-3}$ in the two approaches and consist of three parts: the indirect CP violations in $K^0-{\bar{K}}^0$ mixing $A_{CP,K_{S,L}^0}^{mix}$, the direct CP violations in charm decays $A_{CP,K_{S,L}^0}^{dir}$ and the new CP violation effects $A_{CP,K_{S,L}^0}^{int}$, which are induced from the interference between two tree (Cabibbo-favored and doubly Cabibbo-suppressed) amplitudes with the neutral kaon mixing. The indirect CP violations in $K^0-{\bar{K}}^0$ mixing play a dominant role in $A_{CP}^{K_{S,L}^0}$, the new CP violation effects have a non-negligible contribution to $A_{CP}^{K_{S,L}^0}$. We estimate the numerical results of the $K_S^0-K_L^0$ asymmetries $R_{K_S-K_L}^{D^{\pm }}$ and find that there exist a large difference between the numerical results in the FAT approach and that of the TA approach. We also find that if ones adopt the values of the decay time parameters $t_0=3.0{\tau }_S$ and $t_1=10.0{\tau }_S$, the new CP violation effect $A_{CP,K_S^0}^{int}$ would dominate the CP violation in $D^{\pm }\to K^{\ast }(892{)}^0{\pi }^{\pm }+{\bar{K}}^{\ast }(892{)}^0{\pi }^{\pm }\to K_S^0{\pi }^0{\pi }^{\pm }$ decays and could be observed with $6.7\times 10^6$ and $6.5\times 10^6$ $D^{\pm }$ events-times-efficiency in the FAT approach and the TA approach, respectively. Our results could be tested by the LHCb, Belle II and BESIII experiments.

   hep-phPRD(2023)·3 citations
6. 06*

   Four-body baryonic $B\to {\mathbf{B}}_1{\bar{\mathbf{B}}}_1^{\prime }{\mathbf{B}}_2{\bar{\mathbf{B}}}_2^{\prime }$ decays

   Yu-Kuo Hsiao🇨🇳

   LHCb has recently reported the first observation of a four-body baryonic $B\to {\mathbf{B}}_1{\bar{\mathbf{B}}}_1^{\prime }{\mathbf{B}}_2{\bar{\mathbf{B}}}_2^{\prime }$ decay, where ${\mathbf{B}}_1{\bar{\mathbf{B}}}_1^{\prime }$ and ${\mathbf{B}}_2{\bar{\mathbf{B}}}_2^{\prime }$ represent the two pairs of octet baryon states. In our classification, the measured ${\bar{B}}^0\to p\bar{p}p\bar{p}$ decay is a tree dominated process via internal $W$-boson emission, whose branching fraction is explained as small as $2.2\times 10^{-8}$. We investigate for the first time the phenomenology of other tree and penguin dominated $B\to {\mathbf{B}}_1{\bar{\mathbf{B}}}_1^{\prime }{\mathbf{B}}_2{\bar{\mathbf{B}}}_2^{\prime }$ decays, and predict the presence of a double threshold effect, manifested as two peaks around $m_{{\mathbf{B}}_1{\bar{\mathbf{B}}}_1^{\prime }}\sim m_{{\mathbf{B}}_1}+m_{{\bar{\mathbf{B}}}_1^{\prime }}$ and $m_{{\mathbf{B}}_2{\bar{\mathbf{B}}}_2^{\prime }}\sim m_{{\mathbf{B}}_2}+m_{{\bar{\mathbf{B}}}_2^{\prime }}$ in the invariant mass spectra of ${\mathbf{B}}_1{\bar{\mathbf{B}}}_1^{\prime }$ and ${\mathbf{B}}_2{\bar{\mathbf{B}}}_2^{\prime }$, respectively. Moreover, we predict the following branching fractions: $\mathcal{B}(B^{-}\to n\bar{p}p\bar{p})=(1.7_{-0.2}^{+0.4}\pm 0.1_{-0.4}^{+0.7})\times 10^{-7}$, $\mathcal{B}(B^{-}\to \Lambda \bar{p}p\bar{p})=(7.4_{-0.2}^{+0.6}\pm 0.03_{-2.6}^{+3.6})\times 10^{-7}$, and $\mathcal{B}({\bar{B}}_s^0\to \Lambda \bar{\Lambda }p\bar{p})=(1.9_{-0.1}^{+0.3}\pm 0.01_{-0.6}^{+1.1})\times 10^{-7}$, which are accessible to experimental facilities.

   hep-phhep-exPLB(2023)·11 citations
7. 07*

   Limits on Dark Photons, Scalars, and Axion-Electromagnetodynamics with The ORGAN Experiment

   Ben T. McAllister🇦🇺 · Aaron Quiskamp🇦🇺 · Ciaran O'Hare🇦🇺 · Paul Altin🇦🇺 · Eugene Ivanov🇦🇺 · Maxim Goryachev🇦🇺 · Michael Tobar🇦🇺

   Axions are a well-motivated dark matter candidate, with a host of experiments around the world searching for direct evidence of their existence. The ORGAN Experiment is a type of axion detector known as an axion haloscope, which takes the form of a cryogenic resonant cavity embedded in a strong magnetic field. ORGAN recently completed Phase 1a, a scan for axions around 65 \textmu eV, and placed the most stringent limits to date on the dark matter axion-photon coupling in this region, $|g_{a\gamma \gamma }|\le 3\times 10^{-12}$. It has been shown that axion haloscopes such as ORGAN are automatically sensitive to other kinds of dark matter candidates, such as dark photons, scalar field/dilaton dark matter, and exotic axion-electromagnetic couplings motivated by quantum electromagnetodynamics. We compute the exclusion limits placed on these various dark matter candidates by ORGAN 1a, and project sensitivity for some future ORGAN phases. In particular, the dark photon limits are the most sensitive to date in some regions of the parameter space.

   hep-phhep-exphysics.ins-detAnnalen Phys.·27 citations
8. 08*

   Explanation of Y(4630) as hadronic resonant state

   Xiao-Hui Mei🇨🇳 · Zhuo Yu🇨🇳 · Mao Song🇨🇳 · Jian-You Guo🇨🇳 · Gang Li🇨🇳 · Xuan Luo🇨🇳

   After Y(4630) is discovered, theorists have given various explanations. We find that if Y(4630) is interpreted as the D-wave resonant state of ${\Lambda }_c{\bar{\Lambda }}_c$ system, the particle mass, decay width and all quantum numbers are consistent with experimental observations. We use the Bonn approximation to get the interaction potential of one boson exchange model, then extend the complex scaling method (CSM) to calculate the bound and resonant states. The results indicate that the ${\Lambda }_c{\bar{\Lambda }}_c$ system can form not only the bound state of S wave, but also the resonant state of the high angular momentum, and the ${}^3{D}_1$ wave resonant state can explain the structure of Y(4630) very well.

   hep-phCPC(2023)·4 citations
9. 09*

   Dark sector tensor currents contribution to lepton's anomalous magnetic moment

   M. Naydenov🇧🇬 · V. Kozhuharov🇧🇬

   In this work we consider a model including dark sector bosons interacting through tensor currents with Standard Model leptons. We show that for certain values of the interaction constant this model has the potential of providing an explanation for the discrepancy between theory and experiment, regarding the anomalous magnetic moment of the muon. The effect on the already established measurements for the electron are small and the lepton universality violation is naturally incorporated. Possible experimental searches together with systematic approach to characteristic properties of the final states are discussed.

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

    Re-evaluating Jet Reconstruction Techniques for New Higgs Boson Searches

    Amit Chakraborty🇮🇳 · Srinandan Dasmahapatra🇬🇧 · Henry Day-Hall🇨🇿 · Billy Ford🇬🇧 · Shubhani Jain🇬🇧 · Stefano Moretti🇬🇧 · Emmanuel Olaiya🇬🇧 · Claire Shepherd-Themistocleous🇬🇧

    The ultimate motivation of our study is to look for signs of physics beyond the Standard Model (BSM). We investigate whether different jet clustering techniques might be more or less suited to the particular final states of interest. In particular, we are interested in fully hadronic final states emerging from the decay chain of the Standard Model like Higgs boson into pairs of light Higgs states, the latter in turn decaying into bottom-anti bottom pairs. We show that, the ability of selecting the multi-jet final state and to reconstruct invariant masses of the Higgs bosons from it depend strongly on the choice of acceptance cuts, resolution parameters and reconstruction algorithm as well as its settings. Hence, we indicate the optimal choice of the latter for the purpose of establishing such a benchmark as a BSM signal. We then repeat the exercise for a heavy Higgs boson cascading into two SM-like Higgs states, obtaining similar results.

    hep-phPoS(2022)·1 citation
11. 11*

    Tracing the emergence of collectivity phenomena in small systems

    B Schenke🇺🇸 · S Schlichting🇩🇪 · P Singh🇫🇮

    We study initial state momentum correlations and event-by-event geometry in p+Pb collisions at $\sqrt{s}=5.02\mathrm{TeV}$ by following the approach of extending the IP-Glasma model to 3D using JIMWLK rapidity evolution. On examining the non-trivial rapidity dependence of the observables, we find that the geometry is correlated over large rapidity intervals, while the initial state momentum correlations have a relatively short range in rapidity. Based on our results, we discuss implications for the relevance of both effects in explaining the origin of collective phenomena in small systems.

    hep-phnucl-thActa Phys.Polon.Supp.(2023)·2 citations
12. 12*

    Accelerated Light Dark Matter-Earth Inelastic Scattering in Direct Detection

    Liangliang Su🇨🇳 · Lei Wu🇨🇳 · Ning Zhou🇨🇳 · Bin Zhu🇨🇳

    The Earth-stopping effect plays a crucial role in the direct detection of sub-GeV dark matter. Besides the elastic scattering process, the quasi-elastic and deep inelastic scatterings between dark matter and nucleus that are usually neglected can dominate the interaction, especially in the accelerated dark matter scenarios, which may affect the dark matter detection sensitivity significantly for the underground experiments. We calculate such inelastic scattering contributions in the Earth-stopping effect and illustrate the essence of our argument with the atmospheric dark matter. With the available data, we find that the resulting upper limits on the atmospheric dark matter-nucleus scattering cross-section can differ from those only considering the elastic scattering process by one order of magnitude.

    hep-phhep-exPRD(2023)·25 citations
13. 13*

    Momentum sum rule and factorization of double parton distributions

    Krzysztof Golec-Biernat🇵🇱 · Anna M. Staśto🇺🇸

    We show that the momentum sum rule is a necessary condition for factorization of double parton distributions into a product of two single parton distributions for small values of the parton momentum fractions x and large enough values of the evolution scale Q. This is a somewhat surprising result since the momentum sum rule involves integration over all values of the momentum fraction. In essence, the momentum sum rule provides a proper relation between the double and single parton distributions, which is necessary for the small x factorization at large $Q$.

    hep-phPRD(2023)·7 citations
14. 14*

    Hot and Dense QCD Shear Viscosity at Leading Log

    Isabella Danhoni🇩🇪 · Guy D. Moore🇩🇪

    The leading-order weak-coupling shear viscosity of QCD was computed almost 20 years ago, and the extension to next-to-leading order is 4 years old. But these results have never been applied at finite baryon chemical potential $\mu$, despite the fact that intermediate-energy heavy ion collisions and merging neutron stars may explore the Quark-Gluon Plasma in a regime where baryon chemical potentials are large. Here we extend the leading-log shear viscosity calculation to finite $\mu$, and we argue that the convergence of the weak-coupling expansion, while questionable for achievable plasmas, should be better at $\mu >T$ than at $\mu =0$.

    hep-phJHEP(2023)·17 citations
15. 15*

    Charged Lepton Flavor Violating Radiative Decays $l_i\to l_j\gamma$ in G2HDM

    Van Que Tran🇨🇳 · Tzu-Chiang Yuan🇹🇼

    We compute the electromagnetic form factors of the $l_i{l}_j\gamma$ vertex at one-loop level in the minimal G2HDM which has a sub-GeV vector dark matter candidate. The results are applied to the radiative decay rates for the charged lepton flavor violating processes $l_i\to l_j\gamma$, and the anomalous magnetic dipole moment and the electric dipole moment of the charged lepton. To numerically compute the branching ratio for $\mu \to e\gamma$ and compare with the latest experimental limit from MEG, we adapt our previous parameter space scan that is consistent with the relic density and constraints from direct searches of dark matter, $W$ and $Z$ mass measurements, as well as the LHC Higgs signal strengths and invisible width. While the extra contributions are at least an order of magnitude smaller than required to explain the $\sim 4.2\sigma$ discrepancy in the muon anomaly, the existing MEG limit imposes stringent constraint on the parameter space. The remaining viable parameter space can be further probed by the MEG II sensitivity for $\mu \to e\gamma$ as well as from the direct searches of sub-GeV dark matter in foreseeable future. Higher loop contributions may be significant to resolve the discrepancy in the muon anomaly and generate a non-vanishing electric dipole moments for the standard model quarks and leptons in G2HDM.

    hep-phJHEP(2023)·8 citations
16. 16*

    23, 381, 6242, 103268, 1743183, ...: Hilbert series for CP-violating operators in SMEFT

    Dan Kondo🇯🇵 · Hitoshi Murayama🇺🇸 · Risshin Okabe🇯🇵

    We introduce a systematic method to classify the Standard Model Effective Field Theory (SMEFT) operators based on their CP properties with the Hilbert series techniques. Our method makes it possible to enumerate operators violating CP symmetry in a few seconds. We present the complete classification of dimension eight operators under CP transformation, and the number of CP-odd or CP-violating operators are listed up to dimension 14. We also provide a companion code in FORM that allows anybody to reproduce our results.

    hep-phJHEP(2023)·22 citations
17. 17*

    Properties of kaon at non-zero temperature and baryon chemical potential

    G. Bozkır🇹🇷 · A. Türkan🇹🇷 · K. Azizi🇮🇷

    We investigate the spectroscopic properties of the strange particle kaon in the framework of hot and dense QCD. To this end, first, we find the perturbative spectral density, which is connected with both the temperature $T$ and the baryon chemical potential ${\mu }_B$. We include the non-perturbative operators as functions of temperature and baryon chemical potential up to mass dimension five. We perform the calculations in momentum space and use the quark propagator in the hot and dense medium. The numerical results at non-zero temperature and baryon chemical potential demonstrate that the mass of the particle rises considerably by increasing the baryon chemical potential at a fixed temperature (for both the zero and non-zero temperatures) up to approximately ${\mu }_B=0.4$ GeV. After this point, it starts to fall by increasing the baryon chemical potential and it apparently vanishes at ${\mu }_B=(1.03-1.15)$ GeV for finite temperatures: The point of apparent vanishing moves to lower baryon chemical potentials by increasing the temperature. At zero temperature, the mass reaches to roughly a fixed value at higher baryon chemical potentials. On the other hand, the decay constant decreases considerably with respect to baryon chemical potential up to roughly ${\mu }_B=0.4$ GeV, but after this point, it starts to increase in terms of the baryon chemical potential at finite temperatures. At $T=0$, the decay constant reaches to a fixed value at higher chemical potentials, as well. Regarding the dependence on the temperature we observe that, at fixed values of baryon chemical potentials, the mass and decay constant remain roughly unchanged up to $T=50$ MeV and $T=70$ MeV respectively, but after these points, the mass starts to fall and the decay constant starts to rise up to a critical temperature $T=155$ MeV, considerably.

    hep-phhep-exhep-latEPJA(2023)·12 citations
18. 18*

    Neutrino-tagged jets at the Electron-Ion Collider

    Miguel Arratia🇺🇸 · Zhong-Bo Kang🇺🇸 · Sebouh J. Paul🇺🇸 · Alexei Prokudin🇺🇸 · Felix Ringer🇺🇸 · Fanyi Zhao🇺🇸

    We explore the potential of jet observables in charged-current deep-inelastic scattering (CC DIS) events at the future Electron-Ion Collider (EIC). Tagging jets with a recoiling neutrino, which can be identified by the event's missing transverse momentum, will allow for flavor-sensitive measurements of Transverse Momentum Dependent parton distribution functions (TMDs). We present the first predictions for transverse-spin asymmetries in azimuthal neutrino-jet correlations and hadron-in-jet measurements. We study the kinematic reach and the precision of these measurements and explore their feasibility using parameterized detector simulations. We conclude that jet production in CC DIS, while challenging in terms of luminosity requirements, will complement the EIC experimental program to study the three-dimensional structure of the nucleon encoded in TMDs.

    hep-phhep-exnucl-exnucl-thPRD(2023)·17 citations
19. 19*

    Testing Lepton Flavor Universality at Future $Z$ Factories

    Tin Seng Manfred Ho🇨🇳 · Xu-Hui Jiang🇨🇳 · Tsz Hong Kwok🇨🇳 · Lingfeng Li🇺🇸 · Tao Liu🇨🇳

    As one of the hypothetical principles in the Standard Model (SM), lepton flavor universality (LFU) should be tested with a precision as high as possible such that the physics violating this principle can be fully examined. The run of $Z$ factory at a future $e^{+}{e}^{-}$ collider such as CEPC or FCC-$ee$ provides a great opportunity to perform this task because of the large statistics and high reconstruction efficiencies for $b$-hadrons at $Z$ pole. In this paper, we present a systematic study on the LFU test in the future $Z$ factories. The goal is three-fold. Firstly, we study the sensitivities of measuring the LFU-violating observables of $b\to c\tau \nu$, $i.e.$, $R_{J/\psi }$, $R_{D_s}$, $R_{D_s^{\ast }}$ and $R_{{\Lambda }_c}$, where $\tau$ decays muonically. For this purpose, we develop the strategies for event reconstruction, based on the track information significantly. Secondly, we explore the sensitivity robustness against detector performance and its potential improvement with the message of event shape or beyond the $b$-hadron decays. A picture is drawn on the variation of analysis sensitivities with the detector tracking resolution and soft photon detectability, and the impact of Fox-Wolfram moments is studied on the measurement of relevant flavor events. Finally, we interpret the projected sensitivities in the SM effective field theory, by combining the LFU tests of $b\to c\tau \nu$ and the measurements of $b\to s{\tau }^{+}{\tau }^{-}$ and $b\to s\bar{\nu }\nu$. We show that the limits on the LFU-violating energy scale can be pushed up to $\sim \mathcal{O}(10)$~TeV for $\lesssim \mathcal{O}(1)$ Wilson coefficients at Tera-$Z$.

    hep-phhep-exPRD(2024)·16 citations
20. 20*

    Machine learning-enhanced search for a vectorlike singlet $B$ quark decaying to a singlet scalar or pseudoscalar

    Jai Bardhan🇮🇳 · Tanumoy Mandal🇮🇳 · Subhadip Mitra🇮🇳 · Cyrin Neeraj🇮🇳

    The presence of a new decay mode relaxes the current mass exclusion limits on vectorlike quarks considerably. We consider the case of a weak-singlet vectorlike $B$ quark that can decay to a singlet scalar or pseudoscalar $\Phi$. In an earlier paper [A. Bhardwaj et al., Roadmap to explore vectorlike quarks decaying to a new scalar or pseudoscalar, Phys. Rev. D, 106 (2022) 095014; arXiv:2203.13753], we mapped the possibilities to explore such setups at the LHC. We showed that it is possible for a $B$ quark to decay into $\Phi$ and the $\Phi$ to dominantly decay to a pair of gluons or $b$ quark(s) without fine-tuning the parameters. In this paper, we present a collider search strategy to look for the pair production of singlet $B$ quarks. If both $B$ quarks decay into $b\Phi$ pairs, the final state is fully hadronic: $BB\to (b\Phi )(b\Phi )\to (bgg)(bgg)/(bbb)(bbb)$, which is very challenging to probe. Therefore, we consider a simpler mixed decay specific to the singlet $B$ case, $BB\to (b\Phi )(tW)$ with a lepton in the final state, to achieve the best sensitivity at the high-luminosity LHC. We use a deep neural network with a weighted cross-entropy loss to separate the signal from the huge SM background. Our analysis shows that large areas of the $M_B-M_{\Phi }$ parameter space are discoverable through this signature. We show how the discovery and exclusion regions scale with the branching ratio in the new decay mode. We also estimate the reach in the inclusive monolepton channel with the same network model.

    hep-phhep-exPRD(2023)·25 citations
21. 21*

    Renormalizable Extension of the Abelian Higgs-Kibble Model with a Dim.6 Derivative Operator

    Daniele Binosi🇮🇹 · Andrea Quadri🇮🇹

    We present a new approach to the consistent subtraction of a non power-counting renormalizable extension of the Abelian Higgs-Kibble (HK) model supplemented by a dim.6 derivative-dependent operator controlled by the parameter $z$. A field-theoretic representation of the physical Higgs scalar by a gauge-invariant variable is used in order to formulate the theory by exploiting a novel differential equation, controlling the dependence of the quantized theory on $z$. These results pave the way to the consistent subtraction by a finite number of physical parameters of some non-power-counting renormalizable models possibly of direct relevance to the study of the Higgs potential at the LHC.

    hep-phhep-thSciPost Phys.Proc.(2023)·0 citations
22. 22*

    Jet quenching for heavy flavors in $AA$ and $pp$ collisions

    B.G. Zakharov🇷🇺

    We perform a global analysis of experimental data on jet quenching for heavy flavors for scenarios with and without quark-gluon plasma formation in $pp$ collisions. We find that the theoretical predictions for the nuclear modification factor $R_{AA}$ for heavy flavors at the LHC energies are very similar for these scenarios, and the results for $R_{AA}$ and $v_2$ agree reasonably with the LHC data. The agreement with data at the RHIC top energy becomes somewhat better for the intermediate scenario, in which the quark-gluon plasma formation in $pp$ collisions occurs only at the LHC energies. Our fits to heavy flavor $R_{AA}$ show that description of jet quenching for heavy flavors requires somewhat bigger ${\alpha }_s$ than data on jet quenching for light hadrons.

    hep-phnucl-thJ.Exp.Theor.Phys.(2023)·1 citation
23. 23*

    The WIMP Paradigm: Theme and Variations

    Jonathan L. Feng🇺🇸

    WIMPs, weakly-interacting massive particles, have been leading candidates for particle dark matter for decades, and they remain a viable and highly motivated possibility. In these lectures, I describe the basic motivations for WIMPs, beginning with the WIMP miracle and its under-appreciated cousin, the discrete WIMP miracle. I then give an overview of some of the basic features of WIMPs and how to find them. These lectures conclude with some variations on the WIMP theme that have by now become significant topics in their own right and illustrate the richness of the WIMP paradigm.

    hep-phastro-ph.COhep-exSciPost Phys.Lect.Notes(2023)·61 citations
24. 24*

    Precision Cosmological Constraints on Atomic Dark Matter

    Saurabh Bansal🇺🇸 · Jared Barron🇨🇦 · David Curtin🇨🇦 · Yuhsin Tsai🇺🇸

    Atomic dark matter is a simple but highly theoretically motivated possibility for an interacting dark sector that could constitute some or all of dark matter. We perform a comprehensive study of precision cosmological observables on minimal atomic dark matter, exploring for the first time the full parameter space of dark QED coupling and dark electron and proton masses $({\alpha }_D,m_{e_D},m_{p_D})$ as well as the two cosmological parameters of aDM mass fraction $f_D$ and temperature ratio $\xi$ at time of SM recombination. We also show how aDM can accommodate the $(H_0,S_8)$ tension from late-time measurements, leading to a better fit than $\Lambda$CDM or $\Lambda$CDM + dark radiation. Furthermore, including late-time measurements leads to closed contours of preferred $\xi$ and dark hydrogen binding energy. The dark proton mass is seemingly unconstrained. Our results serve as an important new jumping-off point for future precision studies of atomic dark matter at non-linear and smaller scales.

    hep-phastro-ph.COJHEP(2023)·52 citations
25. 25*

    The analytic structure of three-point functions from contour deformations

    Markus Q. Huber🇩🇪 · Wolfgang J. Kern🇦🇹 · Reinhard Alkofer🇦🇹

    We explore the analytic structure of three-point functions using contour deformations. This method allows continuing calculations analytically from the spacelike to the timelike regime. We first elucidate the case of two-point functions with explicit explanations how to deform the integration contour and the cuts in the integrand to obtain the known cut structure of the integral. This is then applied to one-loop three-point integrals. We explicate individual conditions of the corresponding Landau analysis in terms of contour deformations. In particular, the emergence and position of singular points in the complex integration plane are relevant to determine the physical thresholds. As an exploratory demonstration of this method's numerical implementation we apply it to a coupled system of functional equations for the propagator and the three-point vertex of ${\varphi }^3$ theory. We demonstrate that under generic circumstances the three-point vertex function displays cuts which can be determined from modified Landau conditions.

    hep-phhep-thPRD(2023)·15 citations
26. 26*

    Soft-collinear gravity with fermionic matter

    Martin Beneke🇩🇪 · Patrick Hager🇩🇪 · Dominik Schwienbacher🇩🇪

    We extend the effective field theory for soft and collinear gravitons to interactions with fermionic matter fields. The full theory features a local Lorentz symmetry in addition to the usual diffeomorphisms, which requires incorporating the former into the soft-collinear gravity framework. The local Lorentz symmetry gives rise to Wilson lines in the effective theory that strongly resemble those in SCET for non-abelian gauge interactions, whereas the diffeomorphisms can be treated in the same fashion as in the case of scalar matter. The basic structure of soft-collinear gravity, which features a homogeneous soft background field, giving rise to a covariant derivative and multipole-expanded covariant Riemann-tensor interactions, remains unaltered and generalises in a natural way to fermion fields.

    hep-phhep-thJHEP(2023)·11 citations
27. 27*

    Extractions of $|V_{ub}|/|V_{cb}|$ from a combined study of the exclusive $b\to u(c)\ell {\nu }_{\ell }$ decays

    Aritra Biswas🇮🇳 · Soumitra Nandi🇮🇳 · Ipsita Ray🇮🇳

    We have extracted the ratio $|V_{ub}|/|V_{cb}|$ from a combined study of the available inputs on $\bar{B}\to (\pi ,\rho ,\omega ){\ell }^{-}{\bar{\nu }}_{\ell }$ and $\bar{B}({\bar{B}}_s)\to (D^{(\ast )},D_s^{(\ast )}){\ell }^{-}{\bar{\nu }}_{\ell }$ ($\ell =\mu$ or $e$) decays. We have done our analysis with and without the inclusion of the available experimental results on the branching fraction $\mathcal{B}\mathcal{R}({\bar{B}}_s\to K^{+}{\mu }^{-}{\bar{\nu }}_{\mu })$ or the ratio of the rates $\Gamma ({\bar{B}}_s\to K^{+}{\ell }^{-}{\bar{\nu }}_{\ell })/\Gamma ({\bar{B}}_s\to D_s^{+}{\ell }^{-}{\bar{\nu }}_{\ell })$. We have used all the available experimental data on the branching fractions in different $q^2$-bins, the available theory inputs on the form factors from lattice and the light cone sum rule (LCSR) approach; analysed the data in different possible scenarios and presented the results. From a combined analysis of all the $b\to c{\ell }^{-}{\bar{\nu }}_{\ell }$ exclusive decays, we have obtained $|V_{cb}|=(40.5\pm 0.6)\times 10^{-3}$ and from all the $b\to u{\ell }^{-}{\bar{\nu }}_{\ell }$ modes, we obtain $|V_{ub}|=(3.46\pm 0.12)\times 10^{-3}$ which changes to $|V_{ub}|=(3.51\pm 0.13)\times 10^{-3}$ after dropping $\mathcal{B}\mathcal{R}({\bar{B}}_s\to K^{+}{\mu }^{-}{\bar{\nu }}_{\mu })$. We hence report the values of the ratio $|V_{ub}|/|V_{cb}|=0.085\pm 0.003$ and $0.087\pm 0.003$ with and without the input from ${\bar{B}}_s\to K^{+}{\mu }^{-}{\bar{\nu }}_{\mu }$ modes, respectively. We have also predicted the ratio $\Gamma ({\bar{B}}_s\to K^{+}{\ell }^{-}{\bar{\nu }}_{\ell })/\Gamma ({\bar{B}}_s\to D_s^{+}{\ell }^{-}{\bar{\nu }}_{\ell })$ using the fit results. In addition, we provide the predictions of $\mathcal{B}\mathcal{R}({\bar{B}}_s\to K^{+}{\mu }^{-}{\bar{\nu }}_{\mu })$ and $\mathcal{B}\mathcal{R}(\bar{B}\to (\rho ,\omega ){\ell }^{-}{\bar{\nu }}_{\ell })$ in the Standard Model (SM) in small $q^2$-bins.

    hep-phhep-exhep-latJHEP(2023)·17 citations
28. 28*

    Resolving the Flavor Structure in the MFV-SMEFT

    Sebastian Bruggisser🇩🇪 · Danny van Dyk🇬🇧 · Susanne Westhoff🇩🇪

    We constrain the flavor structure of Wilson coefficients in the Standard Model Effective Field Theory (SMEFT) from data. In the SMEFT, new physics effects in couplings of up-type and down-type quarks are related through the Cabibbo-Kobayashi-Maskawa mixing matrix. We exploit this relation to pin down potential new sources of flavor symmetry breaking in a global analysis of high- and low-energy data from the LHC, LEP, and $b$ factory experiments. We demonstrate the power of such an analysis by performing a combined fit of effective four-quark and two-quark couplings contributing to a large set of flavor, top-quark, electroweak, and dijet observables. All four sectors are needed to fully resolve the flavor structure of the four-quark couplings without leaving blind directions in the parameter space. Although we work in the framework of minimal flavor violation, our strategy applies as well to other flavor patterns, like $U(2)$ flavor symmetry or leptoquark scenarios.

    hep-phhep-exJHEP(2023)·52 citations
29. 29*

    A twisted tale of the transverse-mass tail

    Triparno Bandyopadhyay🇮🇳 · Ankita Budhraja🇮🇳 · Samadrita Mukherjee🇮🇳 · Tuhin S. Roy🇮🇳

    We propose a tantalizing possibility that misinterpretation of the reconstructed missing momentum may have yielded the observed discrepancies among measurements of the $W$-mass in different collider experiments. We introduce a proof-of-principle scenario characterized by a new physics particle, which can be produced associated with the $W$-boson in hadron collisions and contributes to the net missing momentum observed in a detector. We show that these exotic events pass the selection criteria imposed by various collaborations at reasonably high rates. Consequently, in the presence of even a handful of these events, a fit based on the ansatz that the missing momentum is primarily due to neutrinos (as it happens in the Standard Model), yields a $W$-boson mass that differs from its true value. Moreover, the best fit mass depends on the nature of the collider and the center-of-mass energy of collisions. We construct a barebones model that demonstrates this possibility quantitatively while satisfying current constraints. Interestingly, we find that the nature of the new physics particle and its interactions appear as a variation of the physics of Axion-like particles after a field redefinition.

    hep-phhep-exJHEP(2023)·13 citations
30. 30*

    Equation of state and Taylor expansions at nonzero isospin chemical potential

    Bastian B. Brandt🇩🇪 · Francesca Cuteri🇩🇪 · Gergely Endrödi🇩🇪

    We compute the equation of state of isospin asymmetric QCD at zero and non-zero temperatures using direct simulations of lattice QCD with three dynamical flavors at physical quark masses. In addition to the pressure and the trace anomaly and their behavior towards the continuum limit, we will particularly discuss the extraction of the speed of sound. Furthermore, we discuss first steps towards the extension of the EoS to small non-zero baryon chemical potentials via Taylor expansion.

    ↳ hep-lathep-phnucl-thPoS(2023)·12 citations
31. 31*

    Ultra High Energy Cosmic Rays -- an Overview

    Roberto Aloisio🇮🇹

    We review the main experimental evidences on ultra high energy cosmic rays and their implications in the physics of these extremely energetic particles, also in connection with dark matter and cosmology. We discuss the basis of theoretical models aiming at explaining observations, highlighting the most relevant open questions in this fascinating field of research.

    ↳ astro-ph.HEhep-phhep-thJ.Phys.Conf.Ser.(2023)·9 citations
32. 32*

    Inflationary Cosmology in a non-minimal $f(R,T)$ gravity theory using a $RT$ mixing term

    Payel Sarkar🇮🇳 · Ashmita🇮🇳 · Prasanta Kumar Das🇮🇳

    We investigate a class of inflationary models in modified gravity theories which contain a non-minimal coupling between gravity and a scalar field $\varphi$ (inflaton) as $f(R,T)=R(1+\alpha +{\kappa }^4\beta T)+{\kappa }^2\gamma T$ where ${\kappa }^2=8\pi G$ where $G$ is the Newton's constant. We consider two inflaton potentials of the form (i) $V=V_0(1+\ln \varphi )$ and (ii) $V_0\frac{\lambda {\varphi }^p}{1+\lambda {\varphi }^p}$. For a range of potential parameters, we explored the constraints on modified gravity parameters i.e. ($\alpha$, $\beta$ and $\gamma$) in three categories -- (i) $\beta \ne 0$, $\alpha =\gamma =0$ (considering $R$ and $RT$ mixing terms), (ii) $\alpha =0$, $\gamma \ne 0$, $\beta \ne 0$ ($RT$ mixing term along with $T$ and $R$ terms) and (iii) $\gamma =0$, $\alpha \ne 0$, $\beta \ne 0$ ($RT$ mixing term along with $R$ term) for the above two potentials. The inclusion of $RT$ mixing term provides the scalar spectral index $n_s$ up to $3\sigma$ limit of PLANCK data, which is $n_s=0.9649\pm 0.0042$ as well as the tensor-to-scalar ratio $r<0.106$ and the e-fold parameter $40<N<70$ for both the potentials.

    ↳ gr-qchep-phPhys.Dark Univ.(2023)·10 citations
33. 33*

    Asteroseismology: Looking for axions in the red supergiant star Alpha Ori

    Clara Severino🇵🇹 · Ilídio Lopes🇵🇹

    In this work, for the first time, we use seismic data as well as surface abundances to model the supergiant $\alpha$-Ori, with the goal of setting an upper bound on the axion-photon coupling constant $g_{a\gamma }$. We found that, in general, the stellar models with $g_{a\gamma }\in [0.002;2.0]\times 10^{-10}{\mathrm{GeV}}^{-1}$ agree with observational data, but beyond that upper limit, we did not find stellar models compatible with the observational constraints, and current literature. From $g_{a\gamma }=3.5\times 10^{-10}{\mathrm{GeV}}^{-1}$ on, the algorithm did not find any fitting model. Nevertheless, all axionic models considered, presented a distinct internal profile from the reference case, without axions. Moreover, as axion energy losses become more significant, the behaviour of the stellar models becomes more diversified, even with very similar input parameters. Nonetheless, the consecutive increments of $g_{a\gamma }$ still show systematic tendencies, resulting from the axion energy losses. Moreover, we establish three important conclusions: (1) The increased luminosity and higher neutrino production are measurable effects, possibly associated with axion energy losses. (2) Stellar models with axion energy loss show a quite distinct internal structure. (3) The importance of future asteroseismic missions in observing low-degree non-radial modes in massive stars:internal gravity waves probe the near-core regions, where axion effects are most intense. Thus, more seismic data will allow us to constrain $g_{a\gamma }$ better and prove or dismiss the existence of axion energy loss inside massive stars.

    ↳ astro-ph.SRastro-ph.HEhep-phphysics.comp-phApJ(2023)·8 citations
34. 34*

    Periodic charge oscillations in the Proca theory

    Bogdan Damski🇵🇱

    We consider the Proca theory of the real massive vector field. There is a locally conserved 4-current operator in such a theory, which one may use to define the charge operator. Accordingly, there are charged states in which the expectation value of the charge operator is non-zero. We take a close look at the charge operator and study the dynamics of the certain class of charged states. For this purpose, we discuss the mean electric field and 4-current in such states. The mean electric field has the periodically oscillating Coulomb component, whose presence explains the periodic charge oscillations. A complementary insight at such a phenomenon is provided by the mean 4-current, whose discussion leads to the identification of a certain paradox. Last but not least, we show that there is a shock wave propagating in the studied system, which affects analyticity of the mean electric field and 4-current.

    ↳ hep-thhep-phNPB(2023)·4 citations
35. 35*

    The glueball spectrum with $N_f=4$ light fermions

    Andreas Athenodorou🇨🇾 · Jacob Finkenrath🇨🇾 · Adam Lantos🇨🇾 · Michael Teper🇬🇧

    We investigate the glueball spectrum for $N_f=4$ fermions corresponding to low pion masses of $m_{\pi }\sim 250$MeV. We do so by making use of configurations produced with maximally twisted fermions within the framework of the Extended Twisted Mass Collaboration (ETMC). We extract states that belong to irreducible representations of the octahedral group of rotations $R$ in combination with the quantum numbers of charge conjugation $C$ and parity $P$, i.e. $R^{PC}$. We implement the Generalized Eigenvalue Problem (GEVP) using a basis consisting only of gluonic operators. The purpose of this work is to investigate the effect of light dynamical quarks on the glueball spectrum and how this compares to the statistically more accurate spectrum of the pure gauge theory. We employed large ensembles of the order of $\sim \mathcal{O}(10\mathrm{K})$ configurations for each of three different lattice spacings. Our results demonstrate that in the scalar channel $A_1^{++}$ we obtain an additional, lightest state due to the inclusion of light dynamical quarks while the next two states are consistent with the lightest two states in the pure gauge theory. By contrast the mass of the lightest tensor glueball $J^{PC}=2^{++}$ appears to be insensitive to the inclusion of sea quarks, as is the mass of the lightest pseudoscalar. In addition we perform an investigation of the low lying spectrum of the representation $A_1^{++}$ for $N_f=2+1+1$ twisted mass quarks with low masses and demonstrate that the extra lowest state depends strongly on the pion mass. This suggests that the ground state of the scalar glueball has a large quark content, possibly representing the decay of a glueball to two pions.

    ↳ hep-lathep-phPoS(2023)·2 citations
36. 36*

    Charge-dependent anisotropic flow in high-energy heavy-ion collisions from relativistic resistive magneto-hydrodynamic expansion

    Kouki Nakamura🇯🇵 · Takahiro Miyoshi🇯🇵 · Chiho Nonaka🇯🇵 · Hiroyuki R. Takahashi🇯🇵

    We have investigated the charge-dependent anisotropic flow in high-energy heavy-ion collisions, using relativistic resistive magneto-hydrodynamics (RRMHD). We consider the optical Glauber model as an initial model of the quark-gluon plasma (QGP) and the solution of the Maxwell equations with source term of the charged particles in two colliding nuclei as initial electromagnetic fields. The RRMHD simulation is performed with these initial conditions in Au-Au and Cu-Au collisions at $\sqrt{s_{\mathrm{NN}}}=200$ GeV. We have calculated the charge-odd contribution to the directed flow $\Delta v_1$ and elliptic flow $\Delta v_2$ in both collisions based on electric charge distributions as a consequence of RRMHD. Our results show that the $\Delta v_1$ and $\Delta v_2$ are approximately proportional to the electrical conductivity ($\sigma$) of the medium. In the $\sigma =0.023{\mathrm{fm}}^{-1}$ case, our result of $\Delta v_1$ is consistent with STAR data in Au-Au collisions. Furthermore, in Cu-Au collisions, $\Delta v_1$ has a non-zero value at $\eta =0$. We conclude that the charge-dependent anisotropic flow is a good probe to extract the electrical conductivity of the QGP medium in high-energy heavy-ion experiments.

    ↳ nucl-thhep-phnucl-exPRC(2023)·17 citations
37. 37*

    Anomalous transport phenomena on the lattice

    Bastian B. Brandt🇩🇪 · Francesca Cuteri🇩🇪 · Gergely Endrődi🇩🇪 · Eduardo Garnacho Velasco🇩🇪 · Gergely Markó🇩🇪

    The interrelation between quantum anomalies and electromagnetic fields leads to a series of non-dissipative transport effects in QCD. In this work we study anomalous transport phenomena with lattice QCD simulations using improved staggered quarks in the presence of a background magnetic field. In particular, we calculate the conductivities both in the free case and in the interacting case, analysing the dependence of these coefficients with several parameters, such as the temperature and the quark mass.

    ↳ hep-lathep-phPoS(2023)·10 citations
38. 38*

    Particle-dimer approach for the Roper resonance in a finite volume

    Daniel Severt🇩🇪 · Maxim Mai🇺🇸 · Ulf-G. Meißner🇩🇪

    We propose a new finite-volume approach which implements two- and three-body dynamics in a transparent way based on an Effective Field Theory Lagrangian. The formalism utilizes a particle-dimer picture and formulates the quantization conditions based on the self-energy of the decaying particle. The formalism is studied for the case of the Roper resonance, using input from lattice QCD and phenomenology. Finally, finite-volume energy eigenvalues are predicted and compared to existing results of lattice QCD calculations. This crucially provides initial guidance on the necessary level of precision for the finite-volume spectrum.

    ↳ hep-lathep-phnucl-thJHEP(2023)·28 citations
39. 39*

    Influence of hyperon-hyperon interaction on the properties of neutron stars

    R. M. Aguirre🇦🇷

    The properties of neutron stars are studied in a composite model of the strong interaction. In the regime of low to medium baryonic densities a covariant hadronic model is adopted which includes an exclusive channel for the hyperon-hyperon interaction mediated by hidden strangeness mesons, which in turn couple to other mesons through polynomial vertices. The new coupling constants are subject to phenomenological constraints. The presence of free quarks in the core of the star is considered by using the Nambu-Jona Lasinio model supplemented with a vector interaction. The deconfinement process is described by a continuous coexistence of phases. Several structure parameters of neutron stars, such as mass-radius relation, moment of inertia, tidal deformability, and the propagation of nonradial f and g-modes within the relativistic Cowling approximation are studied. The predictions of the model are in good agreement with recent observational data, in particular the maximum inertial mass is greater than the observational lower limit of two solar masses.

    ↳ nucl-thastro-ph.HEhep-phJ.Phys.G(2024)·2 citations
40. 40*

    Lattice determination of the topological susceptibility slope ${\chi }^{\prime }$ of $2d{\mathrm{CP}}^{N-1}$ models at large $N$

    Claudio Bonanno🇮🇹

    We compute the topological susceptibility slope ${\chi }^{\prime }$, related to the second moment of the two-point correlator of the topological charge density, of $2d$ ${\mathrm{CP}}^{N-1}$ models for $N=5,11,21$ and $31$ from lattice Monte Carlo simulations. Our strategy consists in performing a double limit: first, we take the continuum limit of ${\chi }^{\prime }$ at fixed smoothing radius in physical units; then, we take the zero-smoothing-radius limit. Since the same strategy can also be applied to $4d$ gauge theories and full QCD, where ${\chi }^{\prime }$ plays an intriguing theoretical and phenomenological role, this work constitutes a step towards the lattice investigation of this quantity in such models.

    ↳ hep-lathep-phhep-thPRD(2023)·21 citations
41. 41*

    The hadronic running of the electromagnetic coupling and electroweak mixing angle

    Teseo San José🇩🇪 · Hartmut Wittig🇩🇪 · Marco Cè🇨🇭 · Antoine Gérardin🇫🇷 · Georg von Hippel🇩🇪 · Harvey B. Meyer🇩🇪 · Kohtaroh Miura🇩🇪 · Konstantin Ottnad🇩🇪 · Andreas Risch🇩🇪 · Jonas Wilhelm🇩🇪

    We present results for the hadronic running of the electromagnetic coupling and the weak mixing angle from simulations of lattice QCD with $N_f=2+1$ flavours of $O(a)$-improved Wilson fermions. Using two different discretisations of the vector current, we compute the quark-connected and -disconnected contributions to the hadronic vacuum polarisation (HVP) functions ${\bar{\Pi }}^{\gamma \gamma }$ and ${\bar{\Pi }}^{Z\gamma }$ for spacelike squared momenta $Q^2\le 7$ ${\mathrm{GeV}}^2$. Our results are extrapolated to the physical point using ensembles at four lattice spacings, with pion masses ranging from 130 to 420 MeV. We observe a tension of up to 3.5 standard deviations between our lattice results for $\Delta {\alpha }_{\mathrm{had}}^{(5)}(-Q^2)$ and estimates based on the $\text{R}$-ratio for space-like momenta in the range $Q^2=3-7\mathrm{Ge}{\mathrm{V}}^2$. To obtain an estimate for $\Delta {\alpha }_{\mathrm{had}}^{(5)}(M_Z^2)$, we employ the Euclidean split technique. The implications for comparison with global electroweak fits are assessed.

    ↳ hep-lathep-phPoS(2023)·2 citations
42. 42*

    Antipodal Self-Duality for a Four-Particle Form Factor

    Lance J. Dixon🇺🇸 · Ömer Gürdoğan🇬🇧 · Yu-Ting Liu🇺🇸 · Andrew J. McLeod🇨🇭 · Matthias Wilhelm🇩🇰

    We bootstrap the symbol of the maximal-helicity-violating four-particle form factor for the chiral part of the stress-tensor supermultiplet in planar $\mathcal{N}=4$ super-Yang-Mills theory at two loops. When minimally normalized, this symbol involves only 34 letters and obeys the extended Steinmann relations in all partially-overlapping three-particle momentum channels. In addition, the remainder function for this form factor exhibits an antipodal self-duality: it is invariant under the combined operation of the antipodal map defined on multiple polylogarithms -- which reverses the order of the symbol letters -- and a simple kinematic map. This self-duality holds on a four-dimensional parity-preserving kinematic hypersurface. It implies the antipodal duality recently noticed between the three-particle form factor and the six-particle amplitude in this theory.

    ↳ hep-thhep-phPRL(2023)·53 citations
43. 43*

    Revisiting Tests of Lorentz Invariance with Gamma-ray Bursts: Effects of Intrinsic Lags

    Valeri Vardanyan🇯🇵 · Volodymyr Takhistov🇯🇵 · Metin Ata🇯🇵 · Kohta Murase🇺🇸

    Due to their cosmological distances high-energy astrophysical sources allow for unprecedented tests of fundamental physics. Gamma-ray bursts (GRBs) comprise among the most sensitive laboratories for exploring the violation of the central physics principle of Lorentz invariance (LIV), by exploiting spectral time lag of arriving photons. It has been believed that GRB spectral lags are inherently related with their luminosities, and intrinsic source contributions, which remain poorly understood, could significantly impact the LIV results. Using a combined sample of 49 long and short GRBs observed by the Swift telescope, we perform a stacked spectral lag search for LIV effects. We set novel limits on LIV, including limits on quadratic effects, and systematically explore for the first time the impacts of the intrinsic GRB lag-luminosity relation. We find that source contributions can strongly impact resulting LIV tests, modifying their limits by up to a factor of few. We discuss constraints coming from GRB 221009A.

    ↳ astro-ph.HEastro-ph.COhep-phPRD(2023)·17 citations
44. 44*

    Metric anisotropies and nonequilibrium attractor for expanding plasma

    Nisarg Vyas🇮🇳 · Sunil Jaiswal🇮🇳 · Amaresh Jaiswal🇮🇳

    We consider the evolution of a system of chargeless and massless particles in an anisotropic space-time given by the Bianchi type I metric. Specializing to the axis-symmetric case, we derive the framework of anisotropic hydrodynamics from the Boltzmann equation in the relaxation-time approximation. We consider the case of the axis-symmetric Kasner metric and study the approach to the emergent attractor in near and far-off-equilibrium regimes. Further, by relaxing the Kasner conditions on metric coefficients, we study the effect of expansion geometries on the far-off-equilibrium attractor and discuss its implications in the context of relativistic heavy-ion collisions.

    ↳ nucl-thhep-phhep-thPLB(2023)·6 citations
45. 45*

    Prolegomena to a hybrid classical/Rydberg simulator for hadronization (QuPyth)

    Blake Senseman🇺🇸 · Zane Ozzello🇺🇸 · Kenneth Heitritter🇺🇸 · Yannick Meurice🇺🇸 · Stephen Mrenna🇺🇸

    Programmable neutral-atom arrays provide a promising route to real-time analog simulation of strongly interacting quantum systems. We introduce a two leg Rydberg atom ladder that realizes string dynamics and controllable particle production using experimentally accessible parameters. A mapping between local Rydberg occupations and an emergent electric field yields charge anticharge pairs connected by dynamical strings. Classical simulations enforcing Rydberg blockade constraints identify regimes with suppressed entanglement spreading and tunable particle multiplicities, which are seen to be signatures of confinement and string breaking. Particle multiplicities typically grow monotonically with time and system size and depend sensitively on simulator detuning and interaction scales. These results establish the ladder geometry as a viable near-term analog quantum simulator of string fragmentation, and motivate hybrid workflows in which quantum devices contribute nonperturbative real-time dynamics to event generation.

    ↳ quant-phhep-lathep-phPRD(2026)·9 citations
46. 46*

    Boson stars and their relatives in semiclassical gravity

    Miguel Alcubierre🇲🇽 · Juan Barranco🇲🇽 · Argelia Bernal🇲🇽 · Juan Carlos Degollado🇲🇽 · Alberto Diez-Tejedor🇲🇽 · Miguel Megevand🇦🇷 · Darío Núñez🇲🇽 · Olivier Sarbach🇲🇽

    We construct boson star configurations in quantum field theory using the semiclassical gravity approximation. Restricting our attention to the static case, we show that the semiclassical Einstein-Klein-Gordon system for a {\it single real quantum} scalar field whose state describes the excitation of $N$ {\it identical particles}, each one corresponding to a given energy level, can be reduced to the Einstein-Klein-Gordon system for $N$ {\it complex classical} scalar fields. Particular consideration is given to the spherically symmetric static scenario, where energy levels are labeled by quantum numbers $n$, $\ell$ and $m$. When all particles are accommodated in the ground state $n=\ell =m=0$, one recovers the standard static boson star solutions, that can be excited if $n\ne 0$. On the other hand, for the case where all particles have fixed radial and total angular momentum numbers $n$ and $\ell$, with $\ell \ne 0$, but are homogeneously distributed with respect to their magnetic number $m$, one obtains the $\ell$-boson stars, whereas when $\ell =m=0$ and $n$ takes multiple values, the multi-state boson star solutions are obtained. Further generalizations of these configurations are presented, including the multi-$\ell$ multi-state boson stars, that constitute the most general solutions to the $N$-particle, static, spherically symmetric, semiclassical real Einstein-Klein-Gordon system, in which the total number of particles is definite. In spite of the fact that the same spacetime configurations also appear in multi-field classical theories, in semiclassical gravity they arise naturally as the quantum fluctuations associated with the state of a single field describing a many-body system. Our results could have potential impact on direct detection experiments in the context of ultralight scalar field/fuzzy dark matter candidates.

    ↳ gr-qcastro-ph.COhep-phPRD(2023)·33 citations
47. 47*

    Model independent bounds for the number of $e$-folds during the evolution of the universe

    G. German🇲🇽 · R. Gonzalez Quaglia🇲🇽 · A. M. Moran Colorado🇲🇽

    We present a simple procedure to obtain universal bounds for quantities of cosmological interest, such as the number of $e$-folds during inflation, reheating, and radiation, as well as the reheating temperature. The main assumption is to represent each of the various epochs of evolution of the universe as being due to a single substance changing instantaneously into the next, describing a new era of evolution of the universe. This assumption, commonly used to obtain solutions of the Friedmann equations for simple cosmological models, is implemented here to find model-independent bounds on cosmological quantities of interest. In particular, we find that the bound $N_k\approx 56$ for $-\frac{1}{3}<{\omega }_{re}<\frac{1}{3}$ is very robust as an upper bound on the number of $e$-folds during inflation and also as a lower bound when ${\omega }_{re}>\frac{1}{3}$, where ${\omega }_{re}$ is the effective equation of state parameter during reheating. These are model-independent results that any single-field model of inflation should satisfy. As an example, we illustrate the two approaches with the basic $\alpha$ attractor model and show how they complement each other.

    ↳ gr-qcastro-ph.COhep-phhep-thJCAP(2023)·27 citations
48. 48*

    Quantum Electrodynamics of Dicke States: Resonant One-Photon Exchange and Entangled Decay Rate

    U. D. Jentschura🇺🇸 · C. M. Adhikari🇺🇸

    We calculate the one-photon exchange contribution to the interatomic interaction potential between electrically neutral, identical atoms, one of which is assumed to be in an excited state, by matching the scattering matrix (S matrix) element with the effective Hamiltonian. This approach allows us to use covariant perturbation theory, where the two possible time orderings of emission and absorption are summarized in a single Feynman amplitude. Our results encompass the full retardation correction to the one-photon exchange van-der-Waals potential. We employ the temporal gauge for the virtual photon propagator. Based on the Feynman prescription, we obtain the imaginary part of the interaction energy, which leads to an interaction-induced correction to the decay rate. Our results lead to precise formulas for the distance-dependent enhancement and suppression of the decay rates of entangled superradiant and subradiant Dicke state, as a function of the interatomic distance. We apply the result to an example calculation involving two hydrogen atoms, one of which is in the ground state, the other in an excited P state.

    ↳ physics.atom-phhep-phquant-phAtoms(2023)·3 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.