Mon·Feb 19, 2024Monday·February 19, 2024

1. 01*

   Variational Autoencoders for Regression: Recovering Fully Leptonic $b\bar{b}{W}^{+}{W}^{-}$ in Di-Higgs Searches

   Alexandre Alves🇧🇷 · Eduardo da Silva Almeida🇧🇷 · Igor Neiva Mesquita🇧🇷

   The search for double Higgs production in $b\bar{b}{W}^{+}{W}^{-}$, where both $W$ bosons decay to leptons, has been rehabilitated as a good option to look for that key process to the Standard Model scalar sector study in the LHC. The missing neutrinos, however, hinder the reconstruction of useful information like the Higgs pair mass, which is very sensitive to the trilinear Higgs self-coupling. We present a solution to that problem using a Variational Autoencoder for Regression (VAER) to reconstruct the Higgs and top pairs decays $hh,t\bar{t}\to b\bar{b}{W}^{+}{W}^{-}\to b\bar{b}{\ell }^{+}{\ell }^{\prime -}{\nu }_{\ell }{\bar{\nu }}_{{\ell }^{\prime }}$. The algorithm predicts the invariant mass of non-resonant $hh$ irrespective of the trilinear coupling, even for events whose Higgs self-couplings were never presented to it. VAER is also able to identify a new Higgs resonance in an unsupervised way, showing generalization power for events not presented in its training phase. Finally, we demonstrate that VAER prediction is as useful to statistical inference as ground truth simulated distributions by computing a ${\chi }^2$ between trilinear coupling hypotheses based on binned invariant mass distributions of $b\bar{b}{\ell }^{+}{\ell }^{\prime -}{\nu }_{\ell }{\bar{\nu }}_{{\ell }^{\prime }}$.

   hep-phJHEP(2024)·3 citations
2. 02*

   Gravitational signatures of ALP dark matter fragmentation

   Aleksandr Chatrchyan🇩🇪 · Cem Eröncel🇹🇷 · Matthias Koschnitzke🇩🇪 · Géraldine Servant🇩🇪

   The misalignment mechanism for axion-like particles (ALPs) is a leading explanation for dark matter. In this work we investigate ALPs with non-periodic potentials, which allow for large misalignment of the field from the minimum and make it possible for ALPs to match the relic density of dark matter in a large part of the parameter space. Such potentials give rise to self-interactions which can trigger an exponential growth of fluctuations in the ALP field via parametric resonance, leading to the fragmentation of the field. The fluctuations later collapse to halos that can be dense enough to produce observable gravitational effects. These effects would provide a probe of dark matter even if it does not couple to the Standard Model (or too feebly). We determine the relevant regions of parameter space in the (ALP mass, decay constant)-plane and compare predictions in different axion fragmentation models. These proceedings are a short version of arXiv:2305.03756

   hep-phPoS(2024)·2 citations
3. 03*

   Study of $B_s\to \varphi ({\rho }^0,\omega )$ Decays in Standard Model and Family Non-universal $Z^{\prime }$ Model

   Ying Li🇨🇳 · Yue Sun🇨🇳 · Zhi-Tian Zou🇨🇳

   Within QCD factorization approach, we employ the new results of form factors of $B_s\to \varphi$ and calculate the branching fractions, CP asymmetries (CPAs) and polarization fractions of the decay modes $B_s\to \varphi ({\rho }^0,\omega )$ in both the standard model (SM) and the family non-universal $Z^{\prime }$ model. We find that in SM the above observables are relate to two parameters ${\rho }_H$ and ${\varphi }_H$, which characterize the end-point divergence in the hard spectator-scattering amplitudes. When setting ${\rho }_H=0.5$ and ${\varphi }_H\in [-180,180{]}^{\circ }$, the theoretical uncertainties are large. By combining the experimental data, our results can be used to constrain these two parameters. Supposing ${\rho }_H=0$, we study the effects of $Z^{\prime }$ boson on the concerned observables. With the available branching fraction of $B_s\to \varphi {\rho }^0$, the possible ranges of parameter spaces are obtained. Within the allowed parameter spaces, the branching fraction of $B_s\to \varphi \omega$ can be enlarged remarkably. Furthermore, the new introduced weak phase plays important roles in significantly affecting the CPAs and polarization fractions, which are important observables for probing the effects of NP. If these decay modes were measured in the on-going LHC-b and Belle-II experiments in future, the peculiar deviation from SM could provide a signal of the family non-universal $Z^{\prime }$ model, which can also be used to constrain the mass of $Z^{\prime }$ boson in turn.

   hep-phPRD(2024)·0 citations
4. 04*

   The Standard Model quark/lepton masses and the Cabibbo-Kobayashi-Maskawa mixing in an $\mathrm{SU}(8)$ theory

   Ning Chen🇨🇳 · Ying-nan Mao🇨🇳 · Zhaolong Teng🇨🇳

   The observed Standard Model (SM) quark/lepton mass hierarchies and the Cabibbo-Kobayashi-Maskawa (CKM) mixing pattern are described in an $\mathrm{SU}(8)$ theory through its realistic symmetry breaking pattern with three intermediate stages, which rely on a set of $d=5$ gravity-induced operators that break the emergent global symmetries in the chiral fermion sector, as well as the precise identifications of all non-trivially embedded SM flavors.

   hep-phhep-exhep-thJHEP(2024)·9 citations
5. 05*

   Automated resummation of electroweak Sudakov logarithms in diboson production at future colliders

   Ansgar Denner🇩🇪 · Stefan Rode🇩🇪

   At energies that are large with respect to the electroweak scale, the electroweak corrections to scattering processes involve large logarithms that have to be resummed to obtain decent predictions. Soft-collinear effective theory (SCET) has been proposed as a suitable framework to allow for this resummation, while retaining non-logarithmic corrections in a consistent way. In this paper, we investigate the approximations needed to use this approach for the calculation of electroweak corrections to off-shell diboson production at high-energy colliders. Upon implementing the method into a Monte-Carlo integration code, we provide resummed predictions for cross sections and distributions at a 3 TeV lepton collider and a 100 TeV proton collider.

   hep-phEPJC(2024)·21 citations
6. 06*

   Probing the Gauge-boson Couplings of Axion-like Particle at the LHC and High-Luminosity LHC

   Kingman Cheung🇹🇼 · Wanyon Hsiao🇹🇼 · C.J. Ouseph🇹🇼 · Chen Wang🇹🇼

   In this work, we calculate the sensitivities on the gauge-boson couplings $g_{aZZ}$, $g_{aZ\gamma }$, and $g_{aWW}$ of an axion-like particle (ALP) that one can achieve at the LHC with $\sqrt{s}=14$ TeV and integrated luminosities of 300 fb${}^{-1}$ (current run) and 3000 fb${}^{-1}$ (High-Luminosity LHC). We focus on the associated production processes $pp\to Za\to (l^{+}{l}^{-})(\gamma \gamma )$ and $pp\to W^{\pm }a\to (l^{\pm }\nu )(\gamma \gamma )$. We show that better sensitivities on these gauge couplings can be achieved at the LHC for $M_a=1-100$ GeV, down to the level of $10^{-4}{\mathrm{GeV}}^{-1}$. In conclusion, this study emphasizes the significance of the investigated channels in constraining the ALP couplings at the LHC, offering valuable insights for future experiments dedicated to ALP detection.

   hep-phJHEP(2024)·10 citations
7. 07*

   Right-handed neutrino as a common progenitor of baryon number asymmetry and dark matter

   Daijiro Suematsu🇯🇵

   Cosmological and astrophysical observations suggest that both energy densities of baryon and dark matter take the same order values in the present Universe. We propose a scenario to give an answer for this problem in a scotogenic model and its extension. The model naturally provides dark matter candidates as its crucial ingredients to explain the small neutrino mass. If a neutral component of an inert doublet scalar plays a role of dark matter and leptogenesis occurs at TeV scales, both dark matter abundance and baryon number asymmetry could be explained with a same mother particle. Coincidence between the order of their energy densities might be understood through such a background.

   hep-phPRD(2024)·5 citations
8. 08*

   Strong decays of the ${\Lambda }_c(2910)$ and ${\Lambda }_c(2940)$ in the $N{D}^{\ast }$ molecular frame

   Zi-Li Yue🇨🇳 · Quan-Yun Guo🇨🇳 · Dian-Yong Chen🇨🇳

   Stimulated by the observation of a new structure, named ${\Lambda }_c(2910)$, in the ${\Sigma }_c(2455{)}^{0,++}{\pi }^{+,-}$ decay channel from B meson decay process by the Belle Collaboration, and the similarity of the ${\Lambda }_c(2910)/{\Lambda }_c(2940)$ and $P_c$ states, we investigate the decay behavior of the ${\Lambda }_c(2910)$ and ${\Lambda }_c(2940)$ in the $N{D}^{\ast }$ molecular frame with the possible $J^P$ quantum numbers to be $1/2^{-}$ and $3/2^{-}$. We employ an effective Lagrangian approach to evaluate the partial widths of $ND$, ${\Sigma }_c\pi$ and ${\Sigma }_c^{\ast }\pi$ channels. The estimations in the present work indicate that the $J^P$ quantum numbers of ${\Lambda }_c(2910)$ and ${\Lambda }_c(2940)$ are preferred to be $1/2^{-}$ and $3/2^{-}$, respectively. From the present estimations, we also find the branching ratio of ${\Lambda }_c(3/2)\to {\Sigma }_c^{\ast }\pi$ is much larger than that of ${\Lambda }_c(1/2)\to {\Sigma }_c^{\ast }\pi$, thus ${\Sigma }_c^{\ast }\pi$ could be a good channel to distinguish the $J^P$ quantum numbers of ${\Lambda }_c(2910)$ and ${\Lambda }_c(2940)$. Therefore, we suggest to searching for the structure in ${\Sigma }_c^{\ast }\pi$ invariant mass distribution in Belle $⨿$.

   hep-phPRD(2024)·19 citations
9. 09*

   M1 Radiative and spin-nonflip $\pi \pi$ transitions of $B_c$ states in the Cornell potential model

   Zhi-bin Gao🇨🇳 · Yan-yue Fan🇨🇳 · Hao Chen🇨🇳 · Cheng-qun Pang🇨🇳

   In this paper, we mainly predict the rates of $M$1 radiative and spin-nonflip $\pi \pi$ transitions of the $B_c$-meson under the nonrelativistic Cornell potential model with a screening potential effect. We employ the numerical wave function to determine the $M$1 radiative transition widths of $B_c$ excited states and utilize the Kuang-Yan proposed method for the spin-nonflip $\pi \pi$ transitions among $B_c$ states. Our theoretical results are valuable for studying the $M$1 radiative and spin-nonflip $\pi \pi$ transition processes of $B_c$ states in experiments.

   hep-phPRD(2024)·5 citations
10. 10*

    Gravitational Waves: Echoes of the Biggest Bangs since the Big Bang and/or BSM Physics?

    John Ellis🇬🇧

    "If one could ever prove the existence of gravitational waves, the processes responsible for their generation would probably be much more curious and interesting than even the waves themselves." (Gustav Mie, 1868 - 1957) The discovery of gravitational waves has opened new windows on astrophysics, cosmology and physics beyond the Standard Model (BSM). Measurements by the LIGO, Virgo and KAGRA Collaborations of stellar-mass binaries and neutron star mergers have shown that gravitational waves travel at close to the velocity of light, and also constrain BSM possibilities such as a graviton mass and Lorentz violation in gravitational wave propagation. Follow-up measurements of neutron star mergers have provided evidence for the production of heavy elements, possibly including some essential for human life. The gravitational waves in the nanoHz range observed by Pulsar Timing Arrays (PTAs) may have been emitted by supermassive black hole binaries, but might also have originated from BSM cosmological scenarios such as cosmic strings, or phase transitions in the early Universe. The answer to the question in the title may be provided by gravitational-wave detectors at higher frequencies, such as LISA and atom interferometers.

    hep-phastro-ph.COgr-qchep-exUniverse(2025)·3 citations
11. 11*

    Understanding perturbative and non-perturbative contributions to jets at RHIC

    Isaac Mooney🇺🇸

    Jets, as collections of multi-scale objects, allow for insight into perturbative (high-momentum) processes, but gaining an understanding of the non-perturbative structure within jets such as hadronization effects and the underlying event has been more difficult. In observables sensitive to these non-perturbative effects, a large discrepancy is observed between partonic calculations and experimental data at RHIC. Grooming techniques such as SoftDrop reduce the impact of these non-perturbative effects and isolate the hard radiation associated with the hard scattering for more direct comparison to perturbative calculations. By analogy, CollinearDrop can be used to isolate non-perturbative contributions from a different region of the emission phase space, or the Lund plane, although no measurement of a CollinearDrop observable has yet been published. In these proceedings, we review recent progress on experimentally accessing the perturbative and non-perturbative contributions to jets and their substructure, and discuss potential future measurements at RHIC as a road map toward precision QCD at the EIC.

    hep-phhep-exnucl-ex0 citations
12. 12*

    Global Fit of Electron and Neutrino Elastic Scattering Data to Determine the Strange Quark Contribution to the Vector and Axial Form Factors of the Nucleon

    S.F. Pate🇺🇸 · V. Papavassiliou🇺🇸 · J.P. Schaub🇺🇸 · D.P. Trujillo🇺🇸 · M.V. Ivanov🇧🇬 · M.B. Barbaro🇮🇹 · C. Giusti🇮🇹

    We present a global fit of neutral-current elastic (NCE) neutrino-scattering data and parity-violating electron-scattering (PVES) data with the goal of determining the strange quark contribution to the vector and axial form factors of the proton. Previous fits of this form included data from a variety of PVES experiments (PVA4, HAPPEx, G0, SAMPLE) and the NCE neutrino and anti-neutrino data from BNL E734. These fits did not constrain the strangeness contribution to the axial form factor $G_A^s(Q^2)$ at low $Q^2$ very well because there was no NCE data for $Q^2<0.45$ GeV${}^2$. Our new fit includes for the first time MiniBooNE NCE data from both neutrino and anti-neutrino scattering; this experiment used a hydrocarbon target and so a model of the neutrino interaction with the carbon nucleus was required. Three different nuclear models have been employed: a relativistic Fermi gas model, the SuperScaling Approximation model, and a spectral function model. We find a tremendous improvement in the constraint of $G_A^s(Q^2)$ at low $Q^2$ compared to previous work, although more data is needed from NCE measurements that focus on exclusive single-proton final states, for example from MicroBooNE.

    hep-phhep-exnucl-exnucl-thPRD(2024)·12 citations
13. 13*

    Exploring the Frontiers: Challenges and Theories Beyond the Standard Model

    Dhananjay Saikumar🇬🇧

    Quantum Field Theory (QFT) forms the bedrock of the Standard Model (SM) of particle physics, a powerful framework that delineates the fundamental constituents and interactions of the universe. However, the SM's narrative is incomplete, as it conspicuously fails to account for several empirical phenomena that challenge our current understanding of particle physics. This review meticulously examines three paramount anomalies that elude SM predictions: the elusive nature of dark matter, the Higgs boson's anomalously low mass, and the intricate puzzle of neutrino masses. Through a critical analysis, it delves into the forefront of theoretical advancements proposed to bridge these gaps, notably the Weakly Interacting Massive Particles (WIMPs), Supersymmetry (SUSY), and the intriguing hypothesis of right-handed neutrinos. By synthesizing current research and theoretical models, this review not only elucidates these profound mysteries but also underscores the imperative for a more comprehensive and unified theory of particle physics, setting the stage for future discoveries and theoretical breakthroughs.

    hep-ph7 citations
14. 14*

    New Chinese Facilities for Short-Range Correlation Physics

    Zhihong Ye🇨🇳 · Haojie Zhang🇨🇳 · Yaopeng Zhang🇨🇳 · Haocen Zhao🇨🇳

    This article explores the significant advancements in Short-Range Correlation (SRC) research enabled by the latest Chinese nuclear physics facilities- CSR at HIRFL, HIAF, SHINE, and the upcoming EicC. These facilities introduce cutting-edge technologies and methodologies, addressing existing challenges and broadening the scope for SRC studies. By providing detailed insights into the capabilities and expected contributions of each facility, the paper highlights China's emerging role in the global nuclear physics landscape. The collaborative potential, alongside complementary global efforts, positions these facilities to deeply influence our understanding of nuclear matter's fundamental properties and interactions.

    ↳ nucl-exhep-phEPJA(2024)·7 citations
15. 15*

    In-medium static inter-quark potential on high resolution quenched lattices

    Rasmus N. Larsen🇳🇴 · Gaurang Parkar🇳🇴 · Alexander Rothkopf🇳🇴 · Johannes Heinrich Weber🇩🇪

    We re-investigate the interactions between static color sources in a finite temperature gluonic medium using both high resolution isotropic and anisotropic quenched lattice QCD ensembles. The underlying ill-posed inverse problem, related to the extraction of spectral functions, is attacked with a range of different methods, including Bayesian inference, Padé interpolation and model fits. Among the latter we include a tail amended Gaussian ansatz and a HTL-inspired fit ansatz. We reconfirm the presence of a dominant low-lying spectral feature that supports the existence of a potential picture for the in-medium evolution of the static charges at late real times. Using the raw unmodified lattice data, all applicable methods show clear signs of screening of the real-part of the potential. After applying a subtraction procedure featured in a previous study we find however that screening disappears from the extracted potential. Paths towards the resolution of this puzzle are discussed.

    ↳ hep-lathep-phnucl-thPRD(2024)·9 citations
16. 16*

    Prompt Black Hole Formation in Binary Neutron Star Mergers

    Christian Ecker🇩🇪 · Konrad Topolski🇩🇪 · Matti Järvinen🇰🇷 · Alina Stehr🇩🇪

    We carry out an in-depth analysis of the prompt-collapse behaviour of binary neutron star (BNS) mergers. To this end, we perform more than $80$ general relativistic BNS merger simulations using a family of realistic Equations of State (EOS) with different stiffness, which feature a first order deconfinement phase transition between hadronic and quark matter. From these simulations we infer the critical binary mass $M_{\mathrm{crit}}$ that separates the prompt from the non-prompt collapse regime. We show that the critical mass increases with the stiffness of the EOS and obeys a tight quasi-universal relation, $M_{\mathrm{crit}}/M_{\mathrm{TOV}}\approx 1.41\pm 0.06$, which links it to the maximum mass $M_{\mathrm{TOV}}$ of static neutron stars, and therefore provides a straightforward estimate for the total binary mass beyond which prompt collapse becomes inevitable. In addition, we introduce a novel gauge independent definition for a one-parameter family of threshold masses in terms of curvature invariants of the Riemann tensor which characterizes the development toward a more rapid collapse with increasing binary mass. Using these diagnostics, we find that the amount of matter remaining outside the black hole sharply drops in supercritical mass mergers compared to subcritical ones and is further reduced in mergers where the black hole collapse is induced by the formation of a quark matter core. This implies that $M_{\mathrm{crit}}$, particularly for merger remnants featuring quark matter cores, imposes a strict upper limit on the emission of any detectable electromagnetic counterpart in BNS mergers.

    ↳ astro-ph.HEgr-qchep-phnucl-thPRD(2025)·23 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.