Thu·May 16, 2024Thursday·May 16, 2024

1. 01*

   Incorporating Physical Priors into Weakly-Supervised Anomaly Detection

   Chi Lung Cheng🇺🇸 · Gup Singh🇺🇸 · Benjamin Nachman🇺🇸

   We propose a new machine-learning-based anomaly detection strategy for comparing data with a background-only reference (a form of weak supervision). The sensitivity of previous strategies degrades significantly when the signal is too rare or there are many unhelpful features. Our Prior-Assisted Weak Supervision (PAWS) method incorporates information from a class of signal models to significantly enhance the search sensitivity of weakly supervised approaches. As long as the true signal is in the pre-specified class, PAWS matches the sensitivity of a dedicated, fully supervised method without specifying the exact parameters ahead of time. On the benchmark LHC Olympics anomaly detection dataset, our mix of semi-supervised and weakly supervised learning is able to extend the sensitivity over previous methods by a factor of 10 in cross section. Furthermore, if we add irrelevant (noise) dimensions to the inputs, classical methods degrade by another factor of 10 in cross section while PAWS remains insensitive to noise. This new approach could be applied in a number of scenarios and pushes the frontier of sensitivity between completely model-agnostic approaches and fully model-specific searches.

   hep-phhep-exPRL(2025)·21 citations
2. 02*

   Preheating with deep learning

   Jong-Hyun Yoon🇫🇷 · Simon Cléry🇫🇷 · Mathieu Gross🇫🇷 · Yann Mambrini🇫🇷

   We apply deep learning techniques to the late-time turbulent regime in a post-inflationary model where a real scalar inflaton field and the standard model Higgs doublet interact with renormalizable couplings between them. After inflation, the inflaton decays into the Higgs through a trilinear coupling and the Higgs field subsequently thermalizes with gauge bosons via its $SU(2)\times U(1)$ gauge interaction. Depending on the strength of the trilinear interaction and the Higgs self-coupling, the effective mass squared of Higgs can become negative, leading to the tachyonic production of Higgs particles. These produced Higgs particles would then share their energy with gauge bosons, potentially indicating thermalization. Since the model entails different non-perturbative effects, it is necessary to resort to numerical and semi-classical techniques. However, simulations require significant costs in terms of time and computational resources depending on the model used. Particularly, when $SU(2)$ gauge interactions are introduced, this becomes evident as the gauge field redistributes particle energies through rescattering processes, leading to an abundance of UV modes that disrupt simulation stability. This necessitates very small lattice spacings, resulting in exceedingly long simulation runtimes. Furthermore, the late-time behavior of preheating dynamics exhibits a universal form by wave kinetic theory. Therefore, we analyze patterns in the flow of particle numbers and predict future behavior using CNN-LSTM (Convolutional Neural Network combined with Long Short-Term Memory) time series analysis. In this way, we can reduce our dependence on simulations by orders of magnitude in terms of time and computational resources.

   hep-phastro-ph.COJCAP(2024)·1 citation
3. 03*

   Modular Invariant Hilltop Inflation

   Stephen F. King🇬🇧 · Xin Wang🇬🇧

   In this paper we show that it is possible to achieve successful hilltop inflation in which the inflaton is identified as the modulus field in a modular invariant theory. The dilaton plays a crucial role in shaping the potential. Modular invariant gaugino condensation provides the mechanism for the modulus stabilisation after inflation. The inflationary trajectory lies on the lower boundary of the fundamental domain of the modulus field $\tau$. Inflation starts near the fixed point $\tau =\mathrm{i}$, and ends at a point near $\tau =\omega$, which is the global de Sitter vacuum. We investigate the allowed parameter space for successful modular invariant hilltop inflation.

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

   Tetraquarks from Intrinsic Heavy Quarks

   R. Vogt🇺🇸

   A number of new four-quark states containing from one to four charm or anti-charm quarks have been observed recently. Many of these new states have been discovered at the LHC. The production of these states via intrinsic charm in the proton is investigated. The tetraquark masses obtained in this approach, while dependent on the internal transverse momenta of the partons in the state, are shown to agree well with the measured masses. These calculations can provide some insight into the nature of the tetraquark candidates, whether as a bound meson pair or as a looser configuration of four individual partons. The kinematic distributions of these states as a function of rapidity and transverse momentum are also studied. The possible cross sections for these states are finally considered.

   hep-phPRD(2024)·16 citations
5. 05*

   Thermodynamic Signatures and Phase Transitions in High-Energy Au-Au Collisions

   Murad Badshah🇵🇰 · Muhammad Waqas🇨🇳 · Muhammad Ajaz🇵🇰 · Wolfgang Bietenholz🇲🇽 · Haifa I. Alrebdi🇸🇦 · Mohamed Ben Ammar🇸🇦

   In this study, we systematically investigate the dynamics of various hadrons namely \( \pi^+ \), \( \pi^- \), \( K^+ \), \( K^- \), \( p \), \( \bar{p} \), \( \Lambda \), \( \bar{\Lambda} \), \( \Xi^- \) and \( \bar{\Xi}^+ \) produced in central Au-Au collisions. We analyze data of AGS and RHIC, which span a broad range of collision energies, ranging from \( \sqrt{s_{NN}}\) = 1.9 to 200 GeV. To analyze the transverse momentum (\( p_T \)) and transverse mass (\( m_T \)) distributions, we employ a two-component standard distribution function, achieving a very good representation of the experimental data across these energy regimes. We extract key thermodynamic parameters, including the effective temperature \( T \), the mean transverse momentum \( \langle p_T \rangle \), and the initial temperature \( T_i \), and analyze their dependence on the values of collision energy and particle mass. Our findings reveal a distinct transition behaviour around \( \sqrt{s_{NN}} = 19.6 \) GeV. Below \( \sqrt{s_{NN}} = 19.6 \) GeV, the values of \( T \), \( \langle p_T \rangle \), and \( T_i \) increase monotonically for all hadrons due to higher energy transfer into the system. Above this energy threshold, these extracted parameters plateau, suggesting that the additional energy is utilized as latent heat for phase transition rather than increasing the system's temperature. These observations delineate two distinct regions: a hadron-dominated region at lower energies and a parton-dominated region at higher energies, each potentially indicative of different phases of matter, with the latter possibly signalling the onset of a Quark-Gluon Plasma (QGP). The study thus provides critical insights into the complex interplay of thermodynamics, phase transitions, and particle interactions in high-energy Au-Au collisions.

   hep-phJ.Phys.G(2024)·8 citations
6. 06*

   Mass spectra of strange double charm pentaquarks with strangeness $S=-1$

   Zi-Yan Yang🇨🇳 · Qian Wang🇨🇳 · Wei Chen🇨🇳

   The observation of the $T_{c\bar{s}}(2900)$ indicates the potential existence of strange double charm pentaquarks based on the heavy antidiquark symmetry. We systematically study the mass spectra of strange double charm pentaquarks with strangeness $S=-1$ in both molecular and compact structures for quantum numbers $J^P=1/2^{-}$, $3/2^{-}$, $5/2^{-}$. By constructing the interpolating currents, the mass spectra can be extracted from the two-point correlation functions in the framework of QCD sum rule method. In the molecular picture, we find that the ${\Xi }_c^{+}{D}^{\ast +}$, ${\Xi }_c^{{}^{\prime }+}{D}^{\ast +}$, ${\Xi }_c^{\ast +}{D}^{\ast +}$, ${\Xi }_{cc}^{\ast ++}{K}^{\ast 0}$ and ${\Omega }_{cc}^{\ast ++}{\rho }^0$ may form molecular strange double charm pentaquarks. In both pictures, the masses of the $J^P=1/2^{-},3/2^{-}$ pentaquarks locate within the $4.2-4.6\mathrm{GeV}$ and $4.2-4.5\mathrm{GeV}$ regions, respectively. As all of them are above the thresholds of their strong decay channels, they behave as a broad state, making them challenging to be detected in experiment. On the contrary, the mass of the $J^P=5/2^{-}$ strange double charm pentaquark is located at $4.3\mathrm{GeV}$ and below its strong decay channel. This makes it as a narrow state and easy to be identified in experiment. The best observed channel is its semi-leptonic decay to double charm baryon. As the result, we strongly suggest experiments to search for $J^P=5/2^{-}$ strange double charm pentaquarks as a first try.

   hep-phPRD(2024)·12 citations
7. 07*

   Quantum tomography with $\tau$ leptons at the FCC-ee

   M. Fabbrichesi🇮🇹 · L. Marzola🇪🇪

   The Future Circular Collider (FCC) -- in its first incarnation as a lepton collider -- will produce, according to the proposed design, more than 100 billion pairs of $\tau$ leptons after working for four years at the energy of the $Z$-boson resonance. The $\tau$ lepton is special because its relatively long lifetime makes it possible to reconstruct the momenta of neutrinos emitted in the single pion decay mode. The resulting large number of events is an ideal source for a full quantum tomography of the process that will test quantum entanglement and the violation of Bell inequality with unprecedented precision. In addition, the study of polarizations and spin correlations can provide a competitive determination of the Weinberg angle ${\theta }_W$ and constrain possible anomalous couplings in the neutral electroweak current. We utilize analytic results and Monte Carlo simulations to explore to what extent these goals might be accomplished.

   hep-phhep-exquant-phPRD(2024)·56 citations
8. 08*

   Evidence of the low-lying baryon ${\Sigma }^{\ast }(1/2^{-})$ in the process ${\Lambda }_c^{+}\to \eta {\pi }^{+}\Lambda$

   Wen-Tao Lyu🇨🇳 · Sheng-Chao Zhang🇨🇳 · Guan-Ying Wang🇨🇳 · Jia-Jun Wu🇨🇳 · En Wang🇨🇳 · Li-Sheng Geng🇨🇳 · Ju-Jun Xie🇨🇳

   Motivated by the Belle measurements of the process ${\Lambda }_c^{+}\to \eta {\pi }^{+}\Lambda$, we investigate this process by considering the contributions from the $\Lambda (1670)$, $a_0(980)$, and $\Sigma (1385)$. In addition, we also consider the predicted low-lying baryon ${\Sigma }^{\ast }(1/2^{-})$. Our results involving the ${\Sigma }^{\ast }(1/2^{-})$ are favored by fitting to the Belle data of the $\eta \Lambda$ and ${\pi }^{+}\Lambda$ invariant mass distributions. Furthermore, we predict the $\eta {\pi }^{+}$ invariant mass distribution and the angular distribution $d\Gamma /d\cos \theta$, which are significantly different depending on whether or not the contribution from the ${\Sigma }^{\ast }(1/2^{-})$ is considered. Finally, we show that, with the contribution from the ${\Sigma }^{\ast }(1/2^{-})$, the calculated Dalizt plot agrees with the Belle measurements. Future precise measurements of the process ${\Lambda }_c^{+}\to \eta {\pi }^{+}\Lambda$ could shed further light on the existence of the low-lying ${\Sigma }^{\ast }(1/2^{-})$.

   hep-phPRD(2024)·33 citations
9. 09*

   Tentative estimates of $\mathcal{B}(X(3872)\to {\pi }^0{\pi }^0{\chi }_{c1})$ and $\mathcal{B}(X(3872)\to {\pi }^{+}{\pi }^{-}{\chi }_{c1})$

   N. N. Achasov🇷🇺 · G. N. Shestakov🇷🇺

   The rates of the $X(3872)\to {\pi }^0{\pi }^0{\chi }_{c1}$ and $X(3872)\to {\pi }^{+}{\pi }^{-}{\chi }_{c1}$ decays are estimated in the model of the triangle loop diagrams with charmed $D^{\ast }\bar{D}D$ and ${\bar{D}}^{\ast }D\bar{D}$ mesons in the loops. There are the triangle logarithmic singularities in the physical region of the $X(3872)\to {\pi }^0{\pi }^0{\chi }_{c1}$ decay which manifest themselves as narrow peaks in the ${\pi }^0{\chi }_{c1}$ mass spectrum near the $D^0{\bar{D}}^0$ threshold. The model predicts approximately the same branching fractions of the $X(3872)\to {\pi }^0{\pi }^0{\chi }_{c1}$ and $X(3872)\to {\pi }^{+}{\pi }^{-}{\chi }_{c1}$ decays at the level of about (0.8-1.7)$\times 10^{-4}$. A distinct prediction of the model is the value of the ratio $\mathcal{R}=\mathcal{B}(X(3872)\to {\pi }^{+}{\pi }^{-}{\chi }_{c1})/\mathcal{B}(X(3872)\to {\pi }^0{\pi }^0{\chi }_{c1})\approx 1.1$. It weakly depends on the $X(3872)$ resonance parameters and indicates a significant violation of the isotopic symmetry according to which one would expect $\mathcal{R}=2$.

   hep-phhep-exnucl-exnucl-thPRD(2024)·7 citations
10. 10*

    Origin and detection of nontopological soliton dark matter

    Nicholas Orlofsky🇵🇱

    Macroscopic dark matter like nontopological solitons can form either via the fusion and accumulation of free particles or during cosmological phase transitions. Both mechanisms can create dark matter with large masses ranging from TeV to solar mass. This can lead to interesting targets in direct detection, astrophysical, and cosmological searches.

    hep-phastro-ph.COastro-ph.HE0 citations
11. 11*

    Electromagnetic response of dense quark matter around color-superconducting phase transition and QCD critical point

    Toru Nishimura🇯🇵 · Masakiyo Kitazawa🇯🇵 · Teiji Kunihiro🇯🇵

    We explore how the electric conductivity and associated relaxation time are modified near the QCD critical point and the phase transition to a color superconducting phase using the two-flavor Nambu-Jona-Lasinio model with finite current quark masses. We give a comprehensive account of the nature of the soft modes associated with these phase transitions and how they affect the photon self-energy when the system approaches these phase transitions in a combined way with an emphasis on the common and different aspects in the two transitions. The formalism developed for describing the paraconductivity in metallic superconductors is used for the analysis of the photon self-energy. We show that the transport coefficients calculated from the self-energy show anomalous enhancements in both cases with different critical exponents for the individual transitions. We briefly discuss the possibility of detecting the enhancements in the relativistic heavy-ion collisions in the present and future facilities.

    hep-phAnnals Phys.(2024)·7 citations
12. 12*

    Large solitons flattened by small quantum corrections

    Eduard Kim🇷🇺 · Emin Nugaev🇷🇺 · Yakov Shnir🇷🇺

    We propose a general form of the UV-completed Friedberg-Lee-Sirlin (FLS) model. As can be seen from the mechanical interpretation, UV-completion allows thin-wall approximation for non-topological solitons. The 1-loop renormalized effective potential for the UV-completed FLS model is constructed under the assumption of mass hierarchy. By special choice of parameters, we studied how the Coleman-Weinberg mechanism induces a new mass scale ${\omega }_{-}$ in the classical FLS model. It can be expounded in terms of a stable condensate. As a consequence, the asymptotic of a non-topological soliton's energy at large charge is changed from $\sim Q^{3/4}$ to the linear law.

    hep-phhep-thPLB(2024)·11 citations
13. 13*

    How to fit PDFs in the presence of new physics?

    Elie Hammou🇬🇧

    The interpretation of LHC data, and the assessment of possible hints of new physics, require the precise knowledge of the proton structure in terms of parton distribution functions (PDFs). I present a methodology designed to determine whether and how global PDF fits might inadvertently 'fit away' signs of new physics in the high-energy tails of the distributions. I showcase a scenario for the High-Luminosity LHC, in which the PDFs may completely absorb such signs of new physics, thus biasing theoretical predictions and interpretations. I discuss strategies to single out the effects in this scenario and disentangle the inconsistencies that stem from them. This study brings to light the synergy between the high luminosity programme at the LHC and present and future low-energy non-LHC measurements of large-sea quark distributions. I also present the potential of fitting simultaneously the PDFs and the new physics signals.

    hep-ph2 citations
14. 14*

    Charm CP violation and searches

    Stefan Schacht🇬🇧

    Charm CP violation is a unique gate to the physics of up-type quarks and allows searches for physics beyond the Standard Model in new and exciting ways, complementary to kaon and $b$ decays. We review recent advances, focusing on symmetry-based methods and providing an outlook on the next challenges at the intensity frontier of charm physics.

    hep-phhep-ex1 citation
15. 15*

    Exploring $t$-Channel Models for Dark Matter

    David Cabo-Almeida🇮🇹

    We report on a comprehensive study of the Direct Detection phenomenology of singlet Dark Matter $t$-channel portal models. For that purpose, we present a complete computation of the loop-induced direct detection cross-section for both scalar and fermionic Dark Matter candidates. We complete the study by comparing the results with current and future bounds from Direct Detection experiments and requiring the correct Dark Matter relic density.

    hep-ph0 citations
16. 16*

    Renormalization group running triggered tri-resonant leptogenesis within neutrino flavor-symmetry models

    Zhi-Cheng Liu🇨🇳 · Zhen-hua Zhao🇨🇳

    In this paper, we have studied the consequences of some representative neutrino flavor-symmetry models for tri-resonant leptogenesis (which is realized by having three nearly degenerate right-handed neutrinos). To be specific, we have considered a neutrino flavor-symmetry model realizing the TM1 mixing and modular ${\mathrm{A}}_4^{}$, ${\mathrm{S}}_4^{}$ and ${\mathrm{A}}_5^{}$ symmetry models that have a right-handed neutrino mass matrix $M_{\mathrm{R}}^{}$ as shown in Eq.~(\ref{6}) which gives three exactly degenerate right-handed neutrino masses and consequently prohibits the leptogenesis mechanism to work successfully. For these models, we study the scenario that the desired right-handed neutrino mass splittings for leptogenesis to work are generated from the renormalization-group running effects. In such a scenario, we explore the parameter space that allows for the reproduction of the observed baryon-antibaryon asymmetry of the Universe.

    hep-phEPJC(2025)·2 citations
17. 17*

    Odderon contribution in light of the LHC low-$t$ data

    E. G. S. Luna🇧🇷 · M. G. Ryskin🇷🇺 · V. A. Khoze🇬🇧

    We perform the analysis of elastic scattering $pp$ and $\bar{p}p$ data at low momentum transfer $|t|<0.1$ GeV${}^2$ within large collider energy interval $\sqrt{s}=50$ GeV - 13 TeV in order to evaluate quantitatively the possible Odderon contribution. We use the two-channel eikonal model, which naturally accounts for the screening of the Odderon amplitude by $C$-even (Pomeron) exchanges.

    hep-phhep-exPRD(2024)·10 citations
18. 18*

    Refined determination of the weak mixing angle at low energy

    M. Atzori Corona🇮🇹 · M. Cadeddu🇮🇹 · N. Cargioli🇮🇹 · F. Dordei🇮🇹 · C. Giunti🇮🇹

    The weak mixing angle is a fundamental parameter of the electroweak theory of the standard model whose measurement in the low-energy regime is still not precisely determined. Different probes are sensitive to its value, among which atomic parity violation, coherent elastic neutrino-nucleus scattering and parity-violating electron scattering on different nuclei. In this work, we attempt for the first time to combine all these various determinations by performing a global fit that also keeps into account the unavoidable dependence on the experimentally poorly known neutron distribution radius of the nuclei employed, for which a new measurement using proton-cesium elastic scattering became available. By using all present direct determinations of the neutron distribution radius of cesium we find ${\sin }^2{\vartheta }_W=0.2396_{-0.0019}^{+0.0020}$, which should supersede the previous value determined from atomic parity violation on cesium. When including electroweak only, but also indirect, determinations of the neutron distribution radius of cesium the uncertainty reduces to 0.0017 maintaining the same central value, showing an excellent agreement independently of the method used.

    hep-phhep-exnucl-thPRD(2024)·17 citations
19. 19*

    Analytic forms for the $e^{+}{e}^{-}$ annihilation cross sections around a resonance including initial state radiation

    Baoxin Liu🇨🇳 · Zhenyu Zhang🇨🇳 · Xiang Zhou🇨🇳

    The exact analytic form of cross sections including initial state radiation with Kuraev-Fadin radiative function are obtained for $e^{+}{e}^{-}$ annihilation around a resonance. Despite accounting for vacuum polarization and center-of-mass energy spread effects, the precision remains below 0.1\%, meeting the accuracy requirements of quantum electrodynamics corrections up to $\mathcal{O}({\alpha }^2)$. The analytic forms lead to an enhancement in the precision of experimental measurements of physical parameters, such as branching fractions, and demonstrate significantly improved computational efficiency in the regression procedures.

    hep-phPRD(2024)·0 citations
20. 20*

    Study of possible $DN{D}^{\ast }$ bound states

    Victor Montesinos🇪🇸 · Jing Song🇨🇳 · Wei-Hong Liang🇨🇳 · Eulogio Oset🇪🇸 · Juan Nieves🇪🇸 · Miguel Albaladejo🇪🇸

    We start from a recently favored picture in which the ${\Lambda }_c(2940)$ and ${\Lambda }_c(2910)$ correspond mostly to $N{D}^{\ast }$ bound states with $J^P=1/2^{-},3/2^{-}$ and then add a $D$ as a third particle, looking for the possible binding of the $DN{D}^{\ast }$ three body system within the framework of the Fixed Center Approximation. We find that the system is bound with respect to the corresponding ${\Lambda }_c^{\ast }D$ threshold with a binding of about $60$ MeV and a width of about $90$ MeV. Alternatively we assume a cluster of $ND$ and a $D^{\ast }$ meson interacting with the cluster and we find similar results. The observation of these states of $J^P=1/2^{+},3/2^{+}$ would provide new and valuable information concerning the $DN$ and $D^{\ast }N$ interaction, an issue of current debate.

    hep-phnucl-thPRD(2024)·9 citations
21. 21*

    Thermodynamic properties of a relativistic Bose gas under rigid rotation

    E. Siri🇮🇷 · N. Sadooghi🇮🇷

    We study the thermodynamic properties of a rigidly rotating relativistic Bose gas. First, we derive the solution of the equation of motion corresponding to a rotating complex Klein-Gordon field and determine the free propagator of this model utilizing the Fock-Schwinger proper-time method. Using this propagator, we then obtain the thermodynamic potential of this model in the zeroth and first perturbative level. In addition, we compute the nonperturbative ring contribution to this potential. Our focus is on the dependence of these expressions on the angular velocity, which effectively acts as a chemical potential. Using this thermodynamic potential, we calculate several quantities, including the pressure, angular momentum and entropy densities, heat capacity, speed of sound, and moment of inertia of this rigidly rotating Bose gas as functions of temperature ($T$), angular velocity ($\Omega$), and the coupling constant ($\alpha$). We show that certain thermodynamic instabilities appear at high temperatures and large couplings. They are manifested as zero and negative values of the above quantities, particularly the moment of inertia and heat capacity. Zero moment of inertia leads to the phenomenon of supervorticity at certain $T$ or $\alpha$. Supervortical temperatures (couplings) decrease with increasing coupling (temperature). We also observe superluminal sound velocities at high $T$ and for large $\alpha$.

    hep-phhep-lathep-thnucl-thPRD(2024)·9 citations
22. 22*

    Resonances in $D^0\to {\pi }^{+}{\pi }^{-}{\ell }^{+}{\ell }^{-}$ and sensitivity to New Physics

    Eleftheria Solomonidi🇪🇸

    The study of processes involving the weak decays of the charm quark offers unique possibilities to test the Standard Model from the up-type sector and to probe different New Physics scenarios. In here we focus on the rare decays $D^0\to {\pi }^{+}{\pi }^{-}{\ell }^{+}{\ell }^{-}$. The effectiveness of the Glashow-Iliopoulos-Maiani mechanism in charm results in a series of observables that serve as null tests of the Standard Model. Simultaneously, the dominant Standard Model contribution to such decays comes from long-distance dynamics. Following previous literature we describe this with the mediation of resonances. Motivated by recent experimental results on analogous semileptonic decays we investigate the effect of the $S$-wave of the pion pair by considering the scalar resonance $f_0(500)$. The experimental mass distributions and angular observables are described well with our model and there is a significant improvement on the agreement when accounting for $f_0(500)$, which amounts to around 20\% of the total branching ratio. Furthermore, we propose and estimate the size of a series of additional observables to be measured, which can help probe the $S$-wave and act as complementary null tests of the Standard Model.

    hep-phhep-ex0 citations
23. 23*

    Nonperturbative aspects of the electromagnetic pion form factor at high energies

    Joint Physics Analysis Center: K. Quirion🇺🇸 · C. Fernández-Ramírez🇪🇸 · V. Mathieu🇪🇸 · G. Montaña🇺🇸 · R.J. Perry🇪🇸 · A. Pilloni🇮🇹 · A. Rodas🇺🇸 · V. Shastry🇺🇸 · W.A. Smith🇺🇸 · A.P. Szczepaniak🇺🇸 · D. Winney🇩🇪

    The structure of hadronic form factors at high energies and their deviations from perturbative quantum chromodynamics provide insight on nonperturbative dynamics. Using an approach that is consistent with dispersion relations, we construct a model that simultaneously accounts for the pion wave function, gluonic exchanges, and quark Reggeization. In particular, we find that quark Reggeization can be investigated at high energies by studying scaling violation of the form factor.

    hep-phPRD(2025)·3 citations
24. 24*

    Forward & Far-Forward Heavy Hadrons with JETHAD: A High-energy Viewpoint

    Francesco Giovanni Celiberto🇪🇸

    Inspired by the recent finding that semi-inclusive detections of heavy hadrons exhibit fair stabilization patterns in high-energy resummed distributions against (missing) higher-order corrections, we review and extend our studies on the hadroproduction of light and heavy hadrons tagged in forward and far-forward rapidity ranges. We analyze the NLL/NLO+ behavior of rapidity rates and angular multiplicities via the JETHAD method, where the resummation of next-to-leading energy logarithms and beyond is consistently embodied in the collinear picture. We explore kinematic regions that are within LHC typical acceptances, as well as novel sectors accessible thanks the combined tagging of a far-forward light or heavy hadron at future Forward Physics Facilities and a of central particle at LHC experiments via a precise timing-coincidence setup.

    hep-phhep-exnucl-exnucl-thParticles(2024)·18 citations
25. 25*

    Gravitational wave spectrum from expanding string loops on domain walls: Implication for nanohertz pulsar timing array signal

    Yu Hamada🇩🇪 · Wakutaka Nakano🇯🇵

    We analytically calculate the spectrum of stochastic gravitational waves (GWs) emitted by expanding string loops on domain walls in the scenario where domain walls decay by nucleation of string loops. By introducing macroscopic parameters characterizing the nucleation of the loops, the stochastic GW spectrum is derived in a way that is independent of the details of particle physics models. In contrast to GWs emitted from bubble collisions of the false vacuum decay, the string loops do radiate GWs even when they are perfectly circular before their collisions, resulting in that more and more contribution to the spectrum comes from the smaller and smaller loops compared to the typical size of the collided loops. Consequently, the spectrum is linearly proportional to the frequency at the high-frequency region, which is peculiar to this GW source. Furthermore, the results are compared with the recent nano-Hertz pulsar timing array signal, as well as the projected sensitivity curves of future gravitational wave observatories.

    hep-phastro-ph.COgr-qcPRD(2024)·5 citations
26. 26*

    Fundamental Tests of P and CP Symmetries Using Octet Baryons at the $J/\psi$ Threshold

    Yong Du🇨🇳 · Xiao-Gang He🇨🇳 · Jian-Ping Ma🇨🇳 · Xin-Yu Du🇨🇳

    We systematically investigate tests of the parity P and the combined parity and charge-conjugate CP symmetries from differential angular distributions of $J/\psi$ decaying into the lowest-lying baryon pairs at BESIII and the next-generation super tau-charm facilities (STCFs). Large corrections from $Z$ and $W$ exchange induced parity violating effects are found for $J/\psi$ decays with large logarithms resummed up to $\mathcal{O}({\alpha }_s)$. The parity-violating asymmetries on the production and the decay sides of $J/\psi$ are both estimated to be of $\mathcal{O}(10^{-4})$, thus barely observable with the 10 billion $J/\psi$ events currently collected at BESIII. Nevertheless, these asymmetries utilizing the current BESIII data already permit a measurement of the weak mixing angle with an absolute uncertainty $\delta s_w^2\approx 0.09$, corresponding to the first determination of $s_w^2$ at the $J/\psi$ threshold. In the future, STCFs are estimated to improve this bound by a factor of $\sim 20$ to $\delta s_w^2\approx 0.005$ within one year based on luminosity rescaling. We also obtain the 95% confidence level upper bounds on the electric dipole moments of the octet baryons, which are of $\mathcal{O}(10^{-18})e\mathrm{cm}$ for BESIII and $\mathcal{O}(10^{-19})e\mathrm{cm}$ for STCFs. These bounds are improved by two to three orders of magnitude in comparison with the only existing one on $\Lambda$ from Fermilab. The method discussed in this work also paves a way for a first and direct measurement of the $\Xi$ and $\Sigma$ electric dipole moments.

    hep-phhep-exPRD(2024)·16 citations
27. 27*

    CaloDREAM -- Detector Response Emulation via Attentive flow Matching

    Luigi Favaro🇩🇪 · Ayodele Ore🇩🇪 · Sofia Palacios Schweitzer🇩🇪 · Tilman Plehn🇩🇪

    Detector simulations are an exciting application of modern generative networks. Their sparse high-dimensional data combined with the required precision poses a serious challenge. We show how combining Conditional Flow Matching with transformer elements allows us to simulate the detector phase space reliably. Namely, we use an autoregressive transformer to simulate the energy of each layer, and a vision transformer for the high-dimensional voxel distributions. We show how dimension reduction via latent diffusion allows us to train more efficiently and how diffusion networks can be evaluated faster with bespoke solvers. We showcase our framework, CaloDREAM, on datasets 2 and 3 of the CaloChallenge.

    hep-phSciPost Phys.(2025)·60 citations
28. 28*

    Atmospheric muons and their variations with temperature

    Stef Verpoest🇺🇸 · Dennis Soldin🇺🇸 · Paolo Desiati🇺🇸

    Seasonal variations of atmospheric muons are traditionally interpreted in terms of an effective temperature that relates the atmospheric temperature profile at a given time to the dependence of muon production on atmospheric depth. This paper aims to review and generalize the treatment of muon production and effective temperature that has been used to interpret seasonal variations of atmospheric muons by many experiments. The formalism is developed both in integral form -- for application to compact detectors at a fixed depth that record all muons with $E_{\mu }>E_{\mu }^{\min }$ -- and in differential form -- for application to extended detectors like IceCube, KM3NeT, and Baikal-GVD, where the rates are proportional to energy-dependent effective areas.

    ↳ astro-ph.HEhep-phAstropart.Phys.(2024)·15 citations
29. 29*

    Vacuum energy in the effective field theory of general relativity with a scalar field

    E. Epelbaum🇩🇪 · J. Gegelia🇩🇪 · Ulf-G. Meißner🇩🇪 · L. Neuhaus🇩🇪

    A consistency condition of general relativity as an effective field theory in Minkowskian background uniquely fixes the value of the cosmological constant. In two-loop calculations, including the interaction of gravitons with matter fields, it has been shown that this value of the cosmological constant leads to vanishing vacuum energy, under the assumption that the energy-momentum tensor of the gravitational field is given by the pseudotensor of Landau-Lifshitz's classic textbook. Here, we demonstrate that this result also holds when the self-interaction of a scalar field is taken into account. That is, our two-loop-order calculation suggests that in an effective field theory of metric and scalar fields, one arrives at a consistent theory with massless gravitons if the cosmological constant is fixed from the condition of vanishing vacuum energy. Vice versa, imposing the consistency condition in Minkowskian background leads to a vanishing vacuum energy.

    ↳ hep-thgr-qchep-phPRD(2024)·1 citation
30. 30*

    Exponential Quintessence: curved, steep and stringy?

    David Andriot🇫🇷 · Susha Parameswaran🇬🇧 · Dimitrios Tsimpis🇫🇷 · Timm Wrase🇺🇸 · Ivonne Zavala🇬🇧

    We explore the possibility that our universe's current accelerated expansion is explained by a quintessence model with an exponential scalar potential, $V=V_0{e}^{-\lambda \varphi }$, keeping an eye towards $\lambda \ge \sqrt{2}$ and an open universe, favorable to a string theory realisation and with no cosmological horizon. We work out the full cosmology of the model, including matter, radiation, and optionally negative spatial curvature, for all $\lambda >0$, performing an extensive analysis of the dynamical system and its phase space. The minimal physical requirements of a past epoch of radiation domination and an accelerated expansion today lead to an upper bound $\lambda \lesssim \sqrt{3}$, which is driven slightly up in the presence of observationally allowed spatial curvature. Cosmological solutions start universally in a kination epoch, go through radiation and matter dominated phases and enter an epoch of acceleration, which is only transient for $\lambda >\sqrt{2}$. Field distances traversed between BBN and today are sub-Planckian. We discuss possible string theory origins and phenomenological challenges, such as time variation of fundamental constants. We provide theoretical predictions for the model parameters to be fitted to data, most notably the varying dark energy equation of state parameter, in light of recent results from DES-Y5 and DESI.

    ↳ hep-thastro-ph.COgr-qchep-phJHEP(2024)·62 citations
31. 31*

    Revealing the Production Mechanism of High-Energy Neutrinos from NGC 1068

    Abhishek Das🇺🇸 · B. Theodore Zhang🇯🇵 · Kohta Murase🇺🇸

    The detection of high-energy neutrino signals from the nearby Seyfert galaxy NGC 1068 provides us with an opportunity to study nonthermal processes near the center of supermassive black holes. Using the IceCube and latest Fermi-LAT data, we present general multimessenger constraints on the energetics of cosmic rays and the size of neutrino emission regions. In the photohadronic scenario, the required cosmic-ray luminosity should be larger than about 1-10 percent of the Eddington luminosity, and the emission radius should be less than about 15 Schwarzschild radii in low-beta plasma and less than about 3 Schwarzschild radii in high-beta plasma. The leptonic scenario overshoots the NuSTAR or Fermi-LAT data for any emission radii we consider, and the required gamma-ray luminosity is much larger than the Eddington luminosity. The beta decay scenario also violates not only the energetics requirement but also gamma-ray constraints especially when the Bethe-Heitler and photomeson production processes are consistently considered. Our results rule out the leptonic and beta decay scenarios in a nearly model-independent manner, and support hadronic mechanisms in magnetically-powered coronae if NGC 1068 is a source of high-energy neutrinos.

    ↳ astro-ph.HEastro-ph.GAhep-phApJ(2024)·45 citations
32. 32*

    Orbital Stability Study of the Taiji Space Gravitational Wave Detector

    Yu-Yang Zhang🇨🇳 · Geng Li🇨🇳 · Bo Wen🇨🇳

    Space-based gravitational wave detection is extremely sensitive to disturbances. The Keplerian configuration cannot accurately reflect the variations in spacecraft configuration. Planetary gravitational disturbances are one of the main sources. Numerical simulation is an effective method to investigate the impact of perturbation on spacecraft orbits. This study shows that, in the context of the Taiji project, Earth's gravity is an essential factor in the change in heliocentric formation configuration, contributing to the relative acceleration between spacecrafts in the order of $\mathcal{O}(10^{-6})\mathrm{m}\cdot {\mathrm{s}}^{-2}$. Considering 00:00:00 on 27 October 2032 as the initial orbiting moment, under the influence of Earth's gravitational perturbation, the maximum relative change in armlengths and variation rates of armlengths for Taiji is $1.6\times 10^5\mathrm{km}$, $32\mathrm{m}\cdot {\mathrm{s}}^{-1}$, respectively, compared with the unperturbed Keplerian orbit. Additionally, by considering the gravitational perturbations of Venus and Jupiter, the armlength and relative velocity for Taiji are reduced by $16.01\%$ and $17.45\%$, respectively, compared with when only considering that of Earth. The maximum amplitude of the formation motion indicator changes with the orbit entry time. Results show that the relative velocity increase between the spacecrafts is minimal when the initial orbital moment occurs in July. Moreover, the numerical simulation results are inconsistent when using different ephemerides. The differences between ephemerides DE440 and DE430 are smaller than those between DE440 and DE421.

    ↳ gr-qchep-exhep-phUniverse(2024)·3 citations
33. 33*

    Study of charged Lepton Flavor Violation in electron muon interactions

    Ran Ding🇨🇳 · Jingshu Li🇨🇳 · Meng Lu🇨🇳 · Zhengyun You🇨🇳 · Zijian Wang🇨🇳 · Qiang Li🇨🇳

    With the improvement of muon acceleration technology, it has received great interest to exploit high-energy muon beams for collision or target experiments. We investigate possible charged Lepton Flavor Violation (cLFV) processes mediated by an extra massive neutral gauge boson Zprime in electron muon interactions, either at a proposed electron muon collider or in a fixed target experiment with high-energy muon beam hitting electrons in the target. Based on Monte Carlo calculations and fast detector simulations, we study in detail our signal and possible backgrounds, giving the sensitivity results of cLFV signals at the 90% confidence level. Compared with current and prospective limits set by other experiments, electron muon interactions demonstrate significant advantages in the cLFV coupling strength sensitivity with tau in the final states. In addition, a special cLFV coupling combination, lambda_emu * lambda_mumu, can also be probed in our proposal.

    ↳ hep-exhep-phJHEP(2025)·11 citations
34. 34*

    Constraining UV freeze-in of light relics with current and next-generation CMB observations

    Luca Caloni🇮🇹 · Patrick Stengel🇮🇹 · Massimiliano Lattanzi🇮🇹 · Martina Gerbino🇮🇹

    Cosmological observations allow to measure the abundance of light relics produced in the early Universe. Most studies focus on the thermal freeze-out scenario, yet light relics produced by freeze-in are generic for models in which new light degrees of freedom do not couple strongly enough to the Standard Model (SM) plasma to allow for full thermalization in the early Universe. In ultraviolet (UV) freeze-in scenarios, rates for light relic production associated with non-renormalizable interactions typical of beyond the SM (BSM) models grow with temperature more quickly than the Hubble rate. Thus, relatively small couplings to the SM can be probed by current and next-generation cosmic microwave background (CMB) experiments. We investigate several representative benchmark BSM models, such as axion-like particles from Primakoff production, massless dark photons and light right-handed neutrinos. We calculate contributions to the effective number of neutrino species, $\Delta N_{\mathrm{eff}}$, in corners of parameter space not previously considered and discuss the sensitivity of CMB experiments compared to other probes. In contrast to freeze-out scenarios, $\Delta N_{\mathrm{eff}}$ from UV freeze-in is more dependent on both the specific BSM physics model and the reheating temperature. Depending on the details of the BSM scenario, we find that the sensitivity of next-generation CMB experiments can complement or surpass the current astrophysical, laboratory or collider constraints on the couplings of the SM to the light relic.

    ↳ astro-ph.COhep-phJCAP(2024)·9 citations
35. 35*

    Robust inference of gravitational wave source parameters in the presence of noise transients using normalizing flows

    Chun-Yu Xiong🇨🇳 · Tian-Yang Sun🇨🇳 · Jing-Fei Zhang🇨🇳 · Xin Zhang🇨🇳

    Gravitational wave (GW) detection is of paramount importance in fundamental physics and GW astronomy, yet it presents formidable challenges. One significant challenge is the removal of noise transient artifacts known as glitches, which greatly impact the search and identification of GWs. Recent research has achieved remarkable results in data denoising, often using effective modeling methods to remove glitches. However, for glitches from uncertain or unknown sources, current methods cannot completely eliminate them from the GW signal. In this work, we leverage the inherent robustness of machine learning to obtain reliable posterior parameter distributions directly from GW data contaminated by glitches. Our network model provides reasonable and rapid parameter inference even in the presence of glitches, without needing to remove them. We also investigate various factors affecting the rationality of parameter inference in our normalizing flow network, including glitch and GW parameters. The results demonstrate that the normalizing flow can reasonably infer the source parameters of GWs even with unknown contamination. We find that the nature of the glitch itself is the only factor that can affect the rationality of the inferred results. With improvements to our model, we anticipate accelerating the localization of electromagnetic counterparts and providing priors for more accurate deglitching, thereby speeding up subsequent data processing procedures.

    ↳ gr-qcastro-ph.COastro-ph.IMhep-phPRD(2025)·17 citations
36. 36*

    On the absence of the Chiral Magnetic Effect in equilibrium QCD

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

    In this paper we investigate the chiral magnetic effect (CME): the generation of an electric current due to a homogeneous background magnetic field and a homogeneous chiral imbalance in QCD. We demonstrate that the leading coefficient describing the CME vanishes in equilibrium, both for free fermions as well as in full QCD. Our full QCD results are based on continuum extrapolated lattice simulations using dynamical staggered quarks with physical masses as well as quenched Wilson quarks. We show that it is crucial that a gauge invariant ultraviolet regularization is used to compute the CME and elaborate on why some of the existing in-equilibrium calculations of this effect gave a nonzero result. We stress that our findings imply the absence of a time-independent CME current flowing in equilibrium QCD, but do not concern the CME as an out-of-equilibrium, time-dependent effect.

    ↳ hep-lathep-exhep-phhep-th+1JHEP(2024)·22 citations
37. 37*

    Probing Dark Matter Isocurvature with Primordial Non-Gaussianity

    Michael Geller🇮🇱 · Soubhik Kumar🇺🇸 · Lian-Tao Wang🇺🇸

    Multiple fields can become dynamical during the inflationary epoch. We consider an example where a light field acquires isocurvature fluctuations during inflation and contributes to the dark matter abundance at late times. Interactions between the light field and the adiabatic sector contribute to mixed adiabatic-isocurvature non-Gaussianity (NG). We show the resulting form of NG has a different kinematic dependence than the 'local shape' commonly considered, and highlight the parameter space where a dedicated search is expected to significantly improve the current $\text{Planck}$ sensitivity. We interpret our results in the context of the QCD axion and illustrate how the proposed NG searches can improve upon the existing searches for isocurvature power spectrum and bispectrum.

    ↳ astro-ph.COgr-qchep-phJCAP(2024)·2 citations
38. 38*

    All-order splits and multi-soft limits for particle and string amplitudes

    Nima Arkani-Hamed🇺🇸 · Carolina Figueiredo🇺🇸

    The most important aspects of scattering amplitudes have long been thought to be associated with their poles. But recently a very different sort of "split" factorizations for a wide range of particle and string tree amplitudes have been discovered away from poles. In this paper, we give a simple, conceptual origin for these splits arising from natural properties of the binary geometry of the curve integral formulation for scattering amplitudes for Tr$({\Phi }^3)$ theory. The most natural way of "joining" smaller surfaces to build larger ones directly produces a choice of kinematics for which higher amplitudes factor into lower ones. This gives a generalization of splits to all orders in the topological expansion. These splits allow us to access and compute loop-integrated multi-soft limits for particle and string amplitudes, at all loop orders. This includes split factorizations and multi-soft limits for pion and gluon amplitudes, that are related to Tr$({\Phi }^3)$ theory by a simple kinematical shift.

    ↳ hep-thhep-phJHEP(2025)·55 citations
39. 39*

    Probing Reheating with Gravitational Waves from Graviton Bremsstrahlung

    Basabendu Barman🇮🇳 · Nicolás Bernal🇦🇪 · Simon Cléry🇫🇷 · Yann Mambrini🇫🇷 · Yong Xu🇩🇪 · Óscar Zapata🇨🇴

    In this talk, based on arXiv:2301.11345, arXiv:2305.16388, arXiv:2311.12694, we discuss the production of primordial gravitational waves (GW) sourced by graviton bremsstrahlung during inflationary reheating. For reheating, we consider inflaton decays and annihilations into pairs of bosons or fermions, assuming an inflaton $\varphi$ that oscillates around a generic monomial potential $V(\varphi )\propto {\varphi }^n$. The GW spectrum exhibits distinct features depending on the underlying reheating dynamics, which is controlled by the inflaton potential and the type of coupling between the inflaton and the matter fields. We show that the produced stochastic GW background could be probed in next-generation GW detectors, especially at high frequencies. We further highlight the potential of bremsstrahlung-induced GW to probe the underlying dynamics of reheating.

    ↳ astro-ph.COhep-ph12 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.