Fri·Feb 9, 2024Friday·February 9, 2024

1. 01*

   Perturbative analysis of the three gluon vertex in different gauges at one-loop

   A. Alfaro🇲🇽 · L.X. Gutiérrez Guerrero🇲🇽 · L. Albino🇪🇸 · A. Raya🇲🇽

   In this study, we present a perturbative analysis of the three-gluon vertex for a kinematical symmetric configuration in dimension $n=4-2ϵ$ and different covariant gauges.Our study can describe the form factors of the three gluon vertex in a wide range of momentum. We employ a momentum subtraction (MOM) scheme to define the renormalized vertex. We give an in-depth review of three commonly used vector basis for the vertex, and explicitly show the expressions to change from one basis to the other. Although our estimates are valid only in the perturbative regime, we extend our numerical predictions to the infrared domain and show that in $n=4$ some nonperturbative properties are qualitatively present already at perturbation theory. In particular, we find a critical gauge above which the leading form factor displays the so-called zero crossing. We contrast our findings to those of other models and observe a fairly good agreement.

   hep-phhep-thFew Body Syst.(2024)·0 citations
2. 02*

   Systematic investigation of trace anomaly contribution in nucleon mass

   Xiao-Yun Wang🇨🇳 · Jingxuan Bu🇨🇳

   In this work, under the framework of vector meson dominance model, the trace anomaly contribution value inside neutrons are extracted for the first time based on vector meson photoproduction data. Furthermore, we systematically compare and analyze the trace anomaly contributions of protons and neutrons. The results show that the trace anomaly contributions of protons and neutrons are close, which indirectly confirms that their internal structures and dynamic properties may have certain similarities. In addition, the main factors affecting the extraction of the trace anomaly contribution of nucleons are discussed in detail. This study not only provides a theoretical basis for us to better understand the source of nucleon mass, but also makes a useful exploration and discussion on how to extract the trace anomaly contribution of nucleon more accurately in the future.

   hep-phPRC(2024)·1 citation
3. 03*

   NLO QCD corrections to the $B_c$-pair hadroproduction

   Zi-Qiang Chen🇨🇳 · Long-Bin Chen🇨🇳 · Cong-Feng Qiao🇨🇳

   The $B_c$ meson pair, including pairs of pseudoscalar states and vector states, productions in proton-proton collisions are investigated at the next-to-leading order (NLO) accuracy in the nonrelativistic quantum chromodynamics factorization formalism. The corresponding cross sections at the Large Hadron Collider (LHC) with $\sqrt{s}=14\text{TeV}$ are evaluated. Numerical results indicate that the NLO corrections are substantial, and even dominate over the leading order contributions. Considering the predicted cross sections are sizable, the $B_c$-pair production is expected to be observable at the High-Luminosity LHC experiment.

   hep-phPRD(2024)·4 citations
4. 04*

   Possible scenario of dynamical chiral symmetry breaking in the interacting instanton liquid model

   Yamato Suda🇯🇵 · Daisuke Jido🇯🇵

   We compute the vacuum energy density as a function of the quark condensate in the interacting instanton liquid model (IILM) and examine the pattern of dynamical chiral symmetry breaking from its behavior around the origin. This evaluation is performed by using simulation results of the IILM. We find that chiral symmetry is broken in the U(1)_A anomaly assisted way in the IILM with three-flavor dynamical quarks. We call such a symmetry breaking the anomaly-driven breaking which is one of the scenarios of chiral symmetry breaking proposed in the context of the chiral effective theories. We also find that the instanton-quark interaction included in the IILM plays a crucial role for the anomaly-driven breaking by comparing the full and the quenched IILM calculations.

   hep-phnucl-thPRD(2024)·4 citations
5. 05*

   One-loop QCD corrections to heavy quark angular distributions in DIS

   Qing-Song Chang🇨🇳 · Guang-Peng Zhang🇨🇳

   In this paper we calculate the fully differential cross sections for inclusive heavy quark production in deep-inelastic scattering. We construct proper projection operators to give all possible azimuthal angle distributions of the heavy quark for unpolarized and longitudinally polarized scatterings. These projection operators are expressed in terms of momenta of incoming hadron, virtual photon and detected heavy quark. The azimuthal angle distributions are calculated to next-to-leading order of ${\alpha }_s$, i.e., $O({\alpha }_s^2)$, in a unified way. Analytic expressions of the hard coefficients are given. Numerical results on future electron-ion colliders are also given. It is found that at least three azimuthal angle asymmetries can be more than $1\%$ in typical kinematical regions of these colliders.

   hep-phPRD(2024)·1 citation
6. 06*

   Revisiting azimuthal angular asymmetries in diffractive di-jet production

   Ding Yu Shao🇨🇳 · Yu Shi🇨🇳 · Cheng Zhang🇨🇳 · Jian Zhou🇨🇳 · Ya-jin Zhou🇨🇳

   We explore the impact of initial state soft gluon radiations on the azimuthal angle asymmetries in photo-production of hard di-jet via coherent diffraction in ultraperipheral heavy ion collisions, as well as in electron-proton ($ep$) and electron-nucleus ($eA$) collisions. The primary production mechanism is identified as the diffractive production of two hard jets, accompanied by a collinear gluon emission along the beam direction. In contrast, the diffractive exclusive di-jet production, where the initial state radiation is absent, is suppressed due to color transparency. Our analysis shows that azimuthal asymmetries, traditionally attributed to final state gluon emissions, are reduced by the presence of initial state radiations. The sensitivity of azimuthal asymmetries to both initial and final state radiations suggests that they could provide novel insights into the mechanisms of di-jet production in diffractive processes.

   hep-phJHEP(2024)·17 citations
7. 07*

   Light vector mediators at direct detection experiments

   Valentina De Romeri🇪🇸 · Dimitrios K. Papoulias🇬🇷 · Christoph A. Ternes🇮🇹

   Solar neutrinos induce elastic neutrino-electron scattering in dark matter direct detection experiments, resulting in detectable event rates at current facilities. We analyze recent data from the XENONnT, LUX-ZEPLIN, and PandaX-4T experiments and we derive stringent constraints on several $U(1{)}^{\prime }$ extensions of the Standard Model, accommodating new neutrino-electron interactions. We provide bounds on the relevant coupling and mass of light vector mediators for a variety of models, including the anomaly-free $B-L$ model, lepton flavor-dependent interactions like $L_{\alpha }-L_{\beta }$, $B-2L_e-L_{\mu ,\tau }$, $B-3L_{\alpha }$, and $B+2L_{\mu }+2L_{\tau }$ models. We compare our results with other limits obtained in the literature from both terrestrial and astrophysical experiments. Finally, we present forecasts for improving current bounds with a future experiment like DARWIN.

   hep-phhep-exJHEP(2024)·39 citations
8. 08*

   Quark-hadron duality and the determination of ${\alpha }_s$ from hadronic $\tau$ decay: facts vs. myths

   Diogo Boito🇧🇷 · Maarten Golterman🇺🇸 · Kim Maltman🇨🇦 · Santiago Peris🇪🇸

   Non-perturbative effects have a small but non-trivial impact on the determination of the strong coupling from hadronic $\tau$ decay data. Several approaches have been proposed to take these into account, the two most important of which are the ``truncated OPE'' approach and ``DV-model'' approach. Recently, Pich and Rodríguez-Sánchez have raised a number of criticisms of the latter approach, including, most notably, claims of the existence of (i) a supposed instability with respect to variations of the model for incorporating quark-hadron duality violations, and (ii) an alleged redundancy in the fitting strategy employed in the DV-model approach. In this paper, we address these criticisms one by one, showing they fail to survive more detailed scrutiny of the mathematical or numerical arguments that underpin them. We also show that, while the redundancy claim does not apply to the DV-model approach, it does, in fact, apply to the truncated OPE approach. In particular, the ${\alpha }_s$ value determined in the latter turns out to derive purely from perturbation theory, with no role played by the non-perturbative condensates determined in the rest of the analysis. This leads to the conclusion that a revision of the conventional understanding of what is learned from truncated OPE analyses is necessary and that only very limited self-consistency checks are possible within this framework. These observations raise new, non-trivial issues for the truncated OPE approach.

   hep-phPRD(2025)·6 citations
9. 09*

   Interpretation of excess in $H\to Z\gamma$ using a light axion-like particle

   Kingman Cheung🇹🇼 · C.J. Ouseph🇹🇼

   We interpret the recent excess in a rare decay of the Higgs boson, $H\to Z\gamma$, using a light axion-like particle (ALP) in the massrange $0.05-0.1$ GeV.The dominant decay of such a light ALP is into a pair of collimated photons, whose decay is required to happen before reaching the ECAL detector, such that it mimics a single photon in the detector. It can explain the excess with a coupling $C_{aZH}^{\mathrm{eff}}/\Lambda \sim 4\times 10^{-5}{\mathrm{GeV}}^{-1}$, while the decay of the ALP before reaching the ECAL requires the diphoton coupling $C_{\gamma \gamma }^{\mathrm{eff}}/\Lambda \ge 0.35{\mathrm{TeV}}^{-1}(0.1\mathrm{eV}/m_a{)}^2$. A potential test would be the rare decay of the $Z$ boson $Z\to a{H}^{\ast }\to a(b\bar{b})$ at the Tera-$Z$ option of the future FCC and CEPC. However, it has a branching ratio of only $O(10^{-12})$, and thus barely testable. The production cross section for $pp\to Z^{\ast }\to aH$ via the same coupling $C_{aZH}^{\mathrm{eff}}/\Lambda$ at the LHC is too small for detection.

   hep-phhep-exPRD(2024)·15 citations
10. 10*

    Two-index SU(N) theories: QCD, Orientifolds, Super Yang-Mills, Lattice and Steven Weinberg's $\pi \pi$ scattering legacy

    Francesco Sannino🇮🇹

    I review and improve on how two-index SU(N) gauge-fermion theories help access salient information about the large $N$ vacuum and spectrum of QCD, super Yang Mills and meson-meson scattering. The interplay with recent lattice simulations will be employed to deduce the size of $1/N^2$ corrections. Through the meson-meson scattering analysis I will honor Steven Weinberg's memory by showing how two-index extrapolations naturally accommodate the appearance of tetraquarks states crucial to unitarize meson-meson scattering at low energies.

    hep-phhep-lathep-th1 citation
11. 11*

    Explaining the $B^{+}\to K^{+}\nu \bar{\nu }$ excess via a massless dark photon

    E. Gabrielli🇮🇹 · L. Marzola🇪🇪 · K. Müürsepp🇪🇪 · M. Raidal🇪🇪

    The Belle II collaboration has recently observed the rare decay $B^{+}\to K^{+}\nu \bar{\nu }$, finding an excess with respect to the Standard Model prediction. We explore the possibility that the data entails long-distance interactions induced by a massless dark photon, ${\gamma }_D$. This couples at the tree-level to an invisible, dark sector and to the Standard Model via higher-dimensional operators, such as the chromomagnetic-dipole coupling that we use to explain the excess. As the process $B^{+}\to K^{+}{\gamma }_D$ is forbidden by angular momentum conservation, the transition mediated by the off-shell dark photon yields a three-body final state comprising a pair of dark fermions that show as a missing energy continuum in the detector, faking the neutrino signature. We show that the Belle II data is explained for perturbative values of the parameters of the model. This scenario predicts new contributions to the neutral $B$ meson decays $B^0\to K^{\ast }{\gamma }_D$, in which the emission of a on-shell dark photon is allowed, yielding a monochromatic missing energy signature. Analogously, an excess due to the emission of a dark photon is predicted for the $B_s^0\to \varphi +E_{\mathrm{miss}}$ decay that could be scrutinized next at the LHCb experiments.

    hep-phhep-exEPJC(2024)·47 citations
12. 12*

    The Rise and Fall of the Standard-Model Higgs: Electroweak Vacuum Stability during Kination

    Giorgio Laverda🇵🇹 · Javier Rubio🇪🇸

    In this paper we investigate the vacuum stability of the non-minimally coupled Standard-Model Higgs during a phase of kinetic domination following the end of inflation. The non-minimal coupling to curvature stabilises the Higgs fluctuations during inflation while driving them towards the instability scale during kination, when they can classically overcome the potential barrier separating the false electroweak vacuum from the true one at super-Planckian field values. Avoiding the instability of the Standard-Model vacuum sets an upper bound on the inflationary scale that depends both on the strength of the non-minimal interaction and on the top quark Yukawa coupling. Classical vacuum stability is guaranteed if the gravitationally-produced energy density is smaller than the height of barrier in the effective potential. Interestingly enough, thanks to the explosive particle production in the tachyonic phase, the Higgs itself can be also appointed to the role of reheaton field responsible for the onset of the hot Big Bang era, setting an additional lower bound on the inflationary scale ${\mathcal{H}}_{\inf }\gtrsim 10^{5.5}\text{ GeV}$. Overall, these constraints favour lower masses for the top quark, in agreement with the current measurements of the top quark pole mass. We perform our analysis semi-analytically in terms of the one-loop and three-loop running of the Standard-Model Higgs self-coupling and make use of lattice-based parametric formulas for studying the (re)heating phase derived in arXiv:2307.03774. For a specific choice of $m_t=171.3\text{ GeV}$ we perform also an extensive numerical scanning of the parameter space via classical lattice simulations, identifying stable/unstable regions and supporting the previous analytical arguments. For this fiducial value, the heating of the Universe is achieved at temperatures in the range $10^{-2}-10^9\text{ GeV}$.

    hep-phastro-ph.COgr-qcJHEP(2024)·23 citations
13. 13*

    Birefringence tests of gravity with multi-messenger binaries

    Macarena Lagos🇺🇸 · Leah Jenks🇺🇸 · Maximiliano Isi🇺🇸 · Kenta Hotokezaka🇯🇵 · Brian D. Metzger🇺🇸 · Eric Burns🇺🇸 · Will M. Farr🇺🇸 · Scott Perkins🇺🇸 · Kaze W. K. Wong🇺🇸 · Nicolas Yunes🇺🇸

    Extensions to General Relativity (GR) allow the polarization of gravitational waves (GW) from astrophysical sources to suffer from amplitude and velocity birefringence, which respectively induce changes in the ellipticity and orientation of the polarization tensor. We introduce a multi-messenger approach to test this polarization behavior of GWs during their cosmological propagation using binary sources, for which the initial polarization is determined by the inclination and orientation angles of the orbital angular momentum vector with respect to the line of sight. In particular, we use spatially-resolved radio imaging of the jet from a binary neutron star (BNS) merger to constrain the orientation angle and hence the emitted polarization orientation of the GW signal at the site of the merger, and compare to that observed on Earth by GW detectors. For GW170817 we constrain the deviation from GR due to amplitude birefringence to ${\kappa }_A=-0.12_{-0.61}^{+0.60}$, while the velocity birefringence parameter ${\kappa }_V$ remains unconstrained. The inability to constrain ${\kappa }_V$ is due to the fact that Virgo did not detect GW170817, and measurements of the polarization orientation require information from a combination of multiple detectors with different alignments. For this reason, we also mock future BNS mergers with resolved afterglow proper motion and project that ${\kappa }_V$ could be constrained to a precision of $5$rad (corresponding to an angular shift of the GW polarization of $\delta {\varphi }_V\approx 0.2$rad for a BNS at $100$Mpc) by a future network of third-generation ground-based GW detectors such as Cosmic Explorer and the radio High Sensitivity Array. Crucially, this velocity birefringence effect cannot be constrained with dark binary mergers as it requires polarization information at the emission time, which can be provided only by electromagnetic emission.

    ↳ gr-qcastro-ph.COhep-phPRD(2024)·27 citations
14. 14*

    Starobinsky Inflation and beyond in Einstein-Cartan Gravity

    Minxi He🇰🇷 · Muzi Hong🇯🇵 · Kyohei Mukaida🇯🇵

    We show that various types of scalaron-induced inflation, including the Starobinsky inflation, can be realized in the Einstein-Cartan gravity with the Nieh-Yan term and/or the Holst term. Einstein-Cartan $f(R)$ theory is known not to induce an additional scalar degree of freedom, the scalaron, contrary to the case in the metric formalism. However, there exist geometric quantities other than the Ricci scalar in the Einstein-Cartan gravity, such as the Nieh-Yan and the Holst terms. Once we introduce them in addition to the Ricci scalar and allow general combinations up to their quadratic order, the scalaron can become dynamical to realize inflation. With the rank of the associate matrix of the quadratic part to be one, the models are equivalent to the $\alpha$-attractor inflation and its deformation, including the Starobinsky inflation and quadratic chaotic inflation, etc. For more general cases with the rank greater than one, the models fall into the $k$-essence, realizing the rank one case in a particular limit.

    ↳ gr-qcastro-ph.COhep-phJCAP(2024)·25 citations
15. 15*

    Low-Energy Theorems and Linearity Breaking in Anomalous Amplitudes

    José Fernando Thuorst🇧🇷 · Luciana Ebani🇧🇷 · Thalis José Girardi🇧🇷

    This study seeks a better comprehension of anomalies by exploring (n+1)-point perturbative amplitudes in a 2n-dimensional framework. The involved structures combine axial and vector vertices into odd tensors. This configuration enables diverse expressions, considered identities at the integrand level. However, connecting them is not automatic after loop integration, as the divergent nature of amplitudes links to surface terms. The background to this subject is the conflict between the linearity of integration and the translational invariance observed in the context of anomalies. That makes it impossible to simultaneously satisfy all symmetry and linearity properties, constraints that arise through Ward identities and relations among Green functions. Using the method known as Implicit Regularization, we show that trace choices are a means to select the amount of anomaly contributions appearing in each symmetry relation. Such an idea appeared through recipes to take traces in recent works, but we introduce a more complete view. We also emphasize low-energy theorems of finite amplitudes as the source of these violations, proving that the total amount of anomaly remains fixed regardless of any choices.

    ↳ hep-thhep-phmath-phmath.MPAnnals Phys.(2024)·4 citations
16. 16*

    Robust inference of the Galactic centre gamma-ray excess spatial properties

    Deheng Song🇯🇵 · Christopher Eckner🇫🇷 · Chris Gordon🇳🇿 · Francesca Calore🇫🇷 · Oscar Macias🇺🇸 · Kevork N. Abazajian🇺🇸 · Shunsaku Horiuchi🇯🇵 · Manoj Kaplinghat🇺🇸 · Martin Pohl🇩🇪

    The gamma-ray Fermi-LAT Galactic centre excess (GCE) has puzzled scientists for over 15 years. Despite ongoing debates about its properties, and especially its spatial distribution, its nature remains elusive. We scrutinize how the estimated spatial morphology of this excess depends on models for the Galactic diffuse emission, focusing particularly on the extent to which the Galactic plane and point sources are masked. Our main aim is to compare a spherically symmetric morphology - potentially arising from the annihilation of dark matter (DM) particles - with a boxy morphology - expected if faint unresolved sources in the Galactic bulge dominate the excess emission. Recent claims favouring a DM-motivated template for the GCE are shown to rely on a specific Galactic bulge template, which performs worse than other templates for the Galactic bulge. We find that a non-parametric model of the Galactic bulge derived from the VVV survey results in a significantly better fit for the GCE than DM-motivated templates. This result is independent of whether a GALPROP-based model or a more non-parametric ring-based model is used to describe the diffuse Galactic emission. This conclusion remains true even when additional freedom is added in the background models, allowing for non-parametric modulation of the model components and substantially improving the fit quality. When adopted, optimized background models provide robust results in terms of preference for a boxy bulge morphology of the GCE, regardless of the mask applied to the Galactic plane.

    ↳ astro-ph.GAastro-ph.COastro-ph.HEhep-phMNRAS(2024)·29 citations
17. 17*

    Mass dimension one fermions in FLRW space-time

    Cheng-Yang Lee🇨🇳 · Haomin Rao🇨🇳 · Wenqi Yu🇨🇳 · Siyi Zhou🇨🇳

    Cosmelkology is the study of Elko in cosmology. Elko is a massive spin-half field of mass dimension one. Elko differs from the Dirac and Majorana fermions because it furnishes the irreducible representation of the extended Poincare group with a two-fold Wigner degeneracy where the particle and anti-particle states both have four degrees of freedom. Elko has a renormalizable quartic self interaction which makes it a candidate for self-interacting dark matter. We study Elko in the spatially flat FLRW space-time and find exact solutions in the de Sitter space. By choosing the appropriate solutions and phases, the fields satisfy the canonical anti-commutation relations and have the correct time evolutions in the flat space limit.

    ↳ hep-thastro-ph.COgr-qchep-phEPJC(2025)·6 citations
18. 18*

    Interpretations of the ATLAS measurements of Higgs boson production and decay rates and differential cross-sections in $pp$ collisions at $\sqrt{s}=13$ TeV

    ATLAS Collaboration

    Measurements of the Higgs boson production times decay rates and differential cross-sections have recently been performed by the ATLAS experiment in several decay channels using up to 139 fb${}^{-1}$ of proton-proton collision data at $\sqrt{s}=13$ TeV recorded at the Large Hadron Collider. This paper presents multiple interpretations of these Higgs boson measurements. Measurements of production-mode cross-sections, simplified template cross-sections and fiducial differential cross-sections in different decay channels are reparameterised in terms of the impact of Standard Model effective field theory operators, and constraints are reported on the corresponding Wilson coefficients. Production and decay rate measurements are interpreted in UV-complete extensions of the Standard Model, namely the two-Higgs-doublet model (2HDM) near thealignment limit and the Minimal Supersymmetric Standard Model (MSSM) for various MSSM benchmark scenarios. The constraints on the 2HDM parameters $(\cos (\beta -\alpha ),\tan \beta )$ and the MSSM parameters $(m_A,\tan \beta )$ are complementary to those obtained from direct searches for additional Higgs bosons.

    ↳ hep-exhep-phJHEP(2024)·90 citations
19. 19*

    Chiral spin symmetry and hot QCD

    L. Ya. Glozman🇦🇹

    In this talk we overview main results indicating existence in QCD of three qualitatively different regimes connected by smooth crossovers upon heating: a hadron gas, a stringy fluid and a quark-gluon plasma. In the combined large N_c and chiral limit these regimes likely become distinct phases separated by phase transitions: a chiral restoration phase transition around T_{ch} ~ 130 MeV and a deconfinement phase transition around T_d ~ 300 MeV. It should be an important task to verify this issue on the lattice. We will introduce a chiral spin symmetry, which is a symmetry of the electric part of electrodynamics and of QCD with light quarks. It is realized approximately in QCD above the chiral restoration crossover and disappears in the QGP regime. The center symmetry of the pure glue action and the chiral spin symmetry of the electric part of the QCD Lagrangian with light quarks are complementary to distinguish the confining regime and its disappearance. We also address other lattice evidences for stringy fluid: hadron resonances extracted from the lattice correlators; breakdown of the thermal perturbation theory at T < ~ 600 MeV and fluctuations of conserved charges that point out the N_c scaling above T ~ 155 MeV.

    ↳ hep-lathep-phhep-thnucl-thActa Phys.Polon.Supp.(2024)·3 citations
20. 20*

    Transition dynamics in the ${\Lambda }_{\mathrm{s}}$CDM model: Implications for bound cosmic structures

    Evangelos A. Paraskevas🇬🇷 · Arman Cam🇹🇷 · Leandros Perivolaropoulos🇬🇷 · Ozgur Akarsu🇹🇷

    We explore the predictions of ${\Lambda }_{\mathrm{s}}$CDM, a novel framework suggesting a rapid anti-de Sitter (AdS) to de Sitter (dS) vacua transition in the late Universe, on bound cosmic structures. In its simplest version, the cosmological constant, ${\Lambda }_{\mathrm{s}}$, abruptly switches sign from negative to positive, attaining its present-day value at a redshift of $z_{†}\sim 2$. The ${\Lambda }_{\mathrm{s}}$CDM model emerges as a promising solution to major cosmological tensions, particularly the $H_0$ and $S_8$ tensions, as well as other less definite tensions. A key aspect of our investigation is examining the impact of the abrupt ${\Lambda }_{\mathrm{s}}$CDM model on the formation and evolution of bound cosmic structures. We identify three primary influences: (i) the negative cosmological constant (AdS) phase for $z>z_{†}$, (ii) the abrupt transition marked by a type II (sudden) singularity, leading to an abrupt increase in the universe's expansion rate at $z=z_{†}$, and (iii) an increased expansion rate in the late universe under a positive cosmological constant for $z<z_{†}$, compared to $\Lambda$CDM. Utilizing the spherical collapse model, we investigate the non-linear evolution of bound cosmic structures within the ${\Lambda }_{\mathrm{s}}$CDM framework. We find that the virialization process of cosmic structures, and consequently their matter overdensity, varies depending on whether the AdS-dS transition precedes or follows the turnaround. Specifically, structures virialize with either increased or reduced matter overdensity compared to the Planck-$\Lambda$CDM model, contingent on the timing of the transition. Additionally, our results demonstrate that the sudden singularity does not result in the dissociation of bound systems. Despite its profound nature, the singularity exerts only relatively weak effects on such systems, thereby reinforcing the model's viability in this context.

    ↳ astro-ph.COgr-qchep-phhep-thPRD(2024)·52 citations
21. 21*

    The unexpected uses of a bowling pin: exploiting ${}^{20}$Ne isotopes for precision characterizations of collectivity in small systems

    Giuliano Giacalone🇩🇪 · Benjamin Bally🇫🇷 · Govert Nijs🇨🇭 · Shihang Shen🇩🇪 · Thomas Duguet🇫🇷 · Jean-Paul Ebran🇫🇷 · Serdar Elhatisari🇹🇷 · Mikael Frosini🇫🇷 · Timo A. Lähde🇩🇪 · Dean Lee🇺🇸 · Bing-Nan Lu🇨🇳 · Yuan-Zhuo Ma🇺🇸 and 7 other authors

    Whether or not femto-scale droplets of quark-gluon plasma (QGP) are formed in so-called small systems at high-energy colliders is a pressing question in the phenomenology of the strong interaction. For proton-proton or proton-nucleus collisions the answer is inconclusive due to the large theoretical uncertainties plaguing the description of these processes. While upcoming data on collisions of ${}^{16}$O nuclei may mitigate these uncertainties in the near future, here we demonstrate the unique possibilities offered by complementing ${}^{16}$O${}^{16}$O data with collisions of ${}^{20}$Ne ions. We couple both NLEFT and PGCM ab initio descriptions of the structure of ${}^{20}$Ne and ${}^{16}$O to hydrodynamic simulations of ${}^{16}$O${}^{16}$O and ${}^{20}$Ne${}^{20}$Ne collisions at high energy. We isolate the imprints of the bowling-pin shape of ${}^{20}$Ne on the collective flow of hadrons, which can be used to perform quantitative tests of the hydrodynamic QGP paradigm. In particular, we predict that the elliptic flow of ${}^{20}$Ne${}^{20}$Ne collisions is enhanced by as much as 1.170(8)${}_{stat.}$(30)${}_{syst.}$ for NLEFT and 1.139(6)${}_{stat.}$(39)${}_{syst.}$ for PGCM relative to ${}^{16}$O${}^{16}$O collisions for the 1% most central events. At the same time, theoretical uncertainties largely cancel when studying relative variations of observables between two systems. This demonstrates a method based on experiments with two light-ion species for precision characterizations of the collective dynamics and its emergence in a small system.

    ↳ nucl-thhep-phnucl-exPRL(2025)·105 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.