Tue·May 28, 2024Tuesday·May 28, 2024

1. 01*

   Improving Neutrino Energy Reconstruction with Machine Learning

   Joachim Kopp🇨🇭 · Pedro Machado🇺🇸 · Margot MacMahon🇬🇧 · Ivan Martinez-Soler🇬🇧

   Faithful energy reconstruction is foundational for precision neutrino experiments like DUNE, but is hindered by uncertainties in our understanding of neutrino--nucleus interactions. Here, we demonstrate that dense neural networks are very effective in overcoming these uncertainties by estimating inaccessible kinematic variables based on the observable part of the final state. We find improvements in the energy resolution by up to a factor of two compared to conventional reconstruction algorithms, which translates into an improved physics performance equivalent to a 10-30% increase in the exposure.

   hep-phhep-ex8 citations
2. 02*

   New Higgses at the Electroweak Scale and Differential $t\bar{t}$ Distributions

   Andreas Crivellin🇨🇭

   Indications for new Higgs bosons at 95\,GeV and 152\,GeV with significance of 3.8$\sigma$ and $4.3\sigma$, respectively, have been obtained. While the former contains the inclusive $\gamma \gamma$ channel, the latter is obtained by combining several modes of associated di-photon production, i.e. $\gamma \gamma +X$ with $X=\ell ,\ell b,\mathrm{MET},\tau ,...$, within the $\Delta$SM (the Standard Model extended by a real triplet). Such a triplet predicts a positive definite shift in the $W$ mass, in agreement with the current global electroweak fit, and its neutral component decays dominantly to $W$ bosons (for small mixing angles). This offers a connection to $t\bar{t}$ differential distributions whose experimental signature is $WWb\bar{b}$: A simplified model with a new scalar $H$, produced via gluon fusion and decaying to $S$ and $S^{\prime }$ with subsequent (dominant) decays to $WW$ and $b\bar{b}$, respectively, has the same final state. In fact, adding this new physics polution to the Standard Model describes the leptonic $t\bar{t}$ distributions better by at least $5.8\sigma$. Furthermore, assuming that $S^{\prime }$ is an $SU(2{)}_L$ singlet, the resulting di-photon signal strength is compatible with the 95\,GeV $\gamma \gamma$ measurements. A possible UV completion of this simplified model is the $\Delta$2HDMS, i.e. a 2HDM supplemented with a singlet and a real triplet, which can successfully accommodate electroweak scale Baryogenesis.

   hep-phhep-ex1 citation
3. 03*

   Gauss-Bonnet Cosmology: large-temperature behaviour and bounds from Gravitational Waves

   Anirban Biswas (Yonsei U.)🇰🇷 · Arpan Kar (CQUeST, Seoul)🇰🇷 · Bum-Hoon Lee (CQUeST, Seoul and Sogang U.)🇰🇷 · Hocheol Lee (CQUeST, Seoul and Sogang U.)🇰🇷 · Wonwoo Lee (CQUeST, Seoul)🇰🇷 · Stefano Scopel (CQUeST, Seoul and Sogang U.)🇰🇷 · Liliana Velasco-Sevilla (CQUeST, Seoul and Sogang U.)🇰🇷 · Lu Yin (CQUeST, Seoul and APCTP, Pohang)🇰🇷

   We provide a transparent discussion of the high temperature asymptotic behaviour of Cosmology in a dilaton-Einstein-Gauss-Bonnet (dEGB) scenario of modified gravity with vanishing scalar potential. In particular, we show that it has a clear interpretation in terms of only three attractors (stable critical points) of a set of autonomous differential equations: $w=-\frac{1}{3}$, $w=1$ and $1<w<\frac{7}{3}$, where $w\equiv p/\rho$ is the equation of state, defined as the ratio of the total pressure and the total energy density. All the possible different high-temperature evolution histories of the model are exhausted by only eight paths in the flow of the set of the autonomous differential equations. Our discussion clearly explains why five out of them are characterized by a swift transition of the system toward the attractor, while the remaining three show a more convoluted evolution, where the system follows a meta-stable equation of state at intermediate temperatures before eventually jumping to the real attractor at higher temperatures. Compared to standard Cosmology, the regions of the dEGB parameter space with $w=-\frac{1}{3}$ show a strong enhancement of the expected Gravitational Wave stochastic background produced by the primordial plasma of relativistic particles of the Standard Model. This is due to the very peculiar fact that dEGB allows to have an epoch when the energy density ${\rho }_{\mathrm{rad}}$ of the relativistic plasma dominates the energy of the Universe while at the same time the rate of dilution with $T$ of the total energy density is slower than what usually expected during radiation dominance. This allows to use the bound from BBN to put in dEGB a constraint $T_{\mathrm{RH}}\lesssim 10^8-10^9$ GeV on the reheating temperature of the Universe $T_{\mathrm{RH}}$. Such BBN bound is complementary to late-time constraints from compact binary mergers.

   hep-phastro-ph.COgr-qcJCAP(2024)·6 citations
4. 04*

   The Higgs boson decay $h\to bs$ in the $U(1{)}_X$SSM

   Song Gao🇨🇳 · Shu-Min Zhao🇨🇳 · Ming-Yue Liu🇨🇳 · Xing-Yu Han🇨🇳 · Xi Wang🇨🇳 · Tai-Fu Feng🇨🇳

   In the $U(1{)}_X$SSM, we delve into the flavor violation of $h\to bs$, where $h$ is identified with the SM-like Higgs boson discovered at the LHC. As the U(1) extension of the minimal supersymmetric standard model (MSSM), the U(1)XSSM has new super fields such as right-handed neutrinos and three Higgs singlets. We conduct a thorough analysis of the underlying mechanisms and parameter dependencies of $h\to bs$ in the $U(1{)}_X$SSM. In the $U(1{)}_X$SSM, we discover that the Br$(h\to bs)$ for the Higgs decay to $bs$ could significantly differ from the expectation in the standard model (SM), depending on the values of the new parameters introduced in the model. Our research not only contributes to a deeper understanding of Higgs physics within the $U(1{)}_X$SSM, but also provides valuable guidance for new physics (NP).

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

   A phenomenological estimate of rescattering effects in $B_s\to K^{\ast 0}{\bar{K}}^{\ast 0}$

   Yao Yu🇨🇳 · Hai-Bing Fu🇨🇳 · Han Zhang🇨🇳 · Bai-Cian Ke🇨🇳

   The measurements in $b\to s$ penguin-dominated decays are widely recognized as a powerful test for searching for New Physics by studying the deviation from theoretical estimations within the Standard Model. We examine the final-state rescattering effects on the decay $B_s\to K^{\ast 0}{\bar{K}}^{\ast 0}$ and provide estimations of the branching ratio and longitudinal polarization of $B_s\to K^{\ast 0}{\bar{K}}^{\ast 0}$, which is consistent with experimental observations. Our conclusion is that both short- and long-distance interactions contribute significantly in this decay. The small longitudinal polarization in $B\to VV$ modes may not be a signal for New Physics.

   hep-phEPJC(2025)·7 citations
6. 06*

   Heavy-quark dominance and fine structure of excited heavy baryons ${\Sigma }_Q$, ${\Xi }_Q^{\prime }$ and ${\Omega }_Q$

   Zhen-Yu Li🇨🇳 · Guo-Liang Yu🇨🇳 · Zhi-Gang Wang🇨🇳 · Jian-Zhong Gu🇨🇳

   In the framework of the relativized quark model, the calculation of spin-orbit interactions is improved by considering the contribution from the light quark cluster in a singly heavy baryon. It modifies the energy level splitting of the orbital excitation significantly and causes the emergence of fine structures for ${\Sigma }_Q$, ${\Xi }_Q^{\prime }$ and ${\Omega }_Q$ baryons. Based on this improvement, we systematically analyze the fine structures and retest the heavy quark dominance mechanism. This mechanism is found to be violated in the $1P$-wave states of the ${\Sigma }_c$, ${\Xi }_c^{\prime }$ and ${\Omega }_c$ baryons although it remains effective overall, which may help to understand the nature of the heavy quarks and strong interactions. With the predicted fine structures, we make the precise assignments of those observed heavy baryons which once could not be accurately explained due to their close mass values. The method used in this work is instructive and applicable for the study of more complex exotic hadrons, such as the heavy tetraquarks and pentaquarks.

   hep-phEPJC(2024)·15 citations
7. 07*

   General Discussions on the SU(2) Vector Boson Dark Matter Model with a Single Higgs Multiplet -- Lagrangian, Discrete Subgroups, and Scalar Classifications

   Chun-Xue Yuan🇨🇳 · Zhao Zhang🇨🇳 · Chengfeng Cai🇨🇳 · Yi-Lei Tang🇨🇳 · Hong-Hao Zhang🇨🇳

   The vector boson dark matter particles which stem from some broken gauge symmetries usually requires some unbroken symmetries to keep themselves stable. In the previous literature, some simplest cases have been discussed, in which the unbroken symmetry is provided by a remnant subgroup of the gauge group. It would be interesting to ask whether all the possible remnant subgroups as well as all the possible coupling forms can be enumerated. Classifying all the Higgs components into different mass degenerate representations to simplify the diagonalization processes is also necessary. Rather than the ambitious target of providing a general solution to all kinds of gauge groups configured with all forms of the Higgs multiplets, in this paper, we concentrate on the case of ${\text{SU(2)}}_{\text{D}}$ gauge group together with a single Higgs multiplet. We enumerate all possible discrete subgroups that can survive up to $n=21$, where $n$ is the dimension of the Higgs multiplet. We also provide the general algorithms to enumerate all possible renormalizable operators, to write down the general forms of the vacuum expectation value (VEV) configurations, and to give the detailed results of all the mass degenerate irreducible representations embedded in the Higgs multiplet.

   hep-phhep-thPRD(2025)·2 citations
8. 08*

   Scalar Leptoquark Contribution to Two Photon Elastic Scattering

   Muhammad Omar Nadeem🇵🇰

   We study the contribution of Scalar Leptoquark (SLQ) loops to the two photon scattering cross section at high energies. The leading order helicity amplitudes are discussed at coupling O(e4) for Standard Model (SM) fermions, weak bosons and SLQs. Helicity amplitudes for the different types of loops are calculated for photon center of mass energies being much higher than weak boson mass scale but still much lower than the predicted Leptoquark mass scales. Finally, the cross section due to the SLQ loops is presented in conjunction with the known SM contribution.

   hep-ph0 citations
9. 09*

   Proposal for a Quantum Mechanical Test of Gravity at Millimeter Scale

   Yu Cheng🇨🇳 · Jiadu Lin🇺🇸 · Jie Sheng🇨🇳 · Tsutomu T. Yanagida🇯🇵

   The experimental verification of the Newton law of gravity at small scales has been a longstanding challenge. Recently, torsion balance experiments have successfully measured gravitational force at the millimeter scale. However, testing gravity force on quantum mechanical wave function at small scales remains difficult. In this paper, we propose a novel experiment that utilizes the Josephson effect to detect the different evolution of quantum phase induced from the potential difference caused by gravity. We demonstrate that this experiment can test gravity quantum mechanically at the millimeter scale, and also has a potential to investigate the parity invariance of gravity at small scales.

   hep-phquant-phSci.Rep.(2024)·7 citations
10. 10*

    Revisiting the Higgs Boson Decay into a Photon and a Neutrino Pair

    Aliaksei Kachanovich🇧🇪 · Ivan Nišandžić🇭🇷

    We present new calculations of the leading-order one-loop amplitude and the decay rate for $H\to \nu \bar{\nu }\gamma$ within the standard model, employing reduction to a set of basic Passarino-Veltman functions resulting in more concise expressions compared to prior works. Our result for the total decay rate is $\Gamma (H\to \nu \bar{\nu }\gamma )=1.33\text{keV}$, in close agreement with the narrow width approximation (NWA) for the intermediate Z boson. A comparison with previous results available in the literature is also provided. We evaluate the differential decay rate with respect to the energy of the photon and find that the non-resonant contributions from box diagrams beyond the NWA notably affect the kinematic region associated with high-energy photons, where the intermediate Z boson is offshell. This suggests potential implications for searches of dark sector mediators, particularly in future lepton collider experiments.

    hep-phMod.Phys.Lett.A(2025)·6 citations
11. 11*

    Single and Double Diffractive Production of Dilepton and Photon at LHC

    Gongming Yu🇨🇳 · Rabia Hameed🇨🇳 · Liyuan Hu🇨🇳 · Qiang Hu🇨🇳

    We have investigated the single and double diffractive production of dileptons and photons in ultra-peripheral collisions at the Large Hadron Collider (LHC). Utilizing advanced theoretical models that integrate quantum electrodynamics (QED) and Quantum Chromodynamics (QCD) frameworks, we analyze the differential cross sections of these processes, with particular emphasis on the role of the Pomeron and resolved Pomeron structures, as well as resolved photon structures. Our research employs diffractive production mechanisms to predict dilepton and photon production rates under various LHC energy scenarios. Our results demonstrate distinct production patterns for single and double diffractive processes, highlighting their potential as probes for studying the electromagnetic structure of heavy ions and the dynamics of soft interactions in high-energy collisions. This paper provides new insights into the photon-mediated and Pomeron-mediated production mechanisms and sets the stage for future experimental investigations at collider facilities.

    hep-ph0 citations
12. 12*

    Pion gravitational form factors in the QCD instanton vacuum II

    Wei-Yang Liu🇺🇸 · Edward Shuryak🇺🇸 · Ismail Zahed🇺🇸

    We revisit the hard QCD contributions to the pion gravitational form factors (GFFs), in terms of the twist-2,3 pion distribution amplitudes (DA), including novel semi-hard contributions from the instantons. The pion DAs are evaluated in the QCD instanton vacuum, and then properly evolved to higher resolution. The results are compared to our recent results from the QCD instanton vacuum, as well as Bethe-Salpeter calculations and recent lattice data. The interpolated hard and soft contributions to the pion D-form-factor, are used to derive the (gravitational) pressure and shear within the pion, with a clear delineation of their range.

    hep-phhep-thnucl-thPRD(2024)·25 citations
13. 13*

    An innovative model for coupled fermion-antifermion pairs

    Abdullah Guvendi🇹🇷 · Omar Mustafa🇹🇷

    Understanding the behavior of fermion-antifermion (\(f\overline{f}\)) pairs is crucial in modern physics. These systems, governed by fundamental forces, exhibit complex interactions essential for particle physics, high-energy physics, nuclear physics, and solid-state physics. This study introduces a novel theoretical model using the many-body Dirac equation for \(f\overline{f}\) pairs with an effective position-dependent mass (i.e., \(m \rightarrow m + \mathcal{S}(r)\)) under the influence of an external magnetic field. To validate our model, we show that by modifying the mass with a Coulomb-like potential, \(m(r) = m - \alpha/r\), where \(-\alpha/r\) is the Lorentz scalar potential \(\mathcal{S}(r)\), our results match the well-established energy eigenvalues for \(f\overline{f}\) pairs interacting through the Coulomb potential, without approximation. By applying adjustments based on the Cornell potential (i.e., \(\mathcal{S}(r) = kr - \alpha/r\)), we derive a closed-form energy expression. We believe this unique model offers significant insights into the dynamics of \(f\overline{f}\) pairs under various interaction potentials, with potential applications in particle physics. Additionally, it could be extended to various \(f\overline{f}\) systems, such as positronium, relativistic Landau levels for neutral mesons, excitons in monolayer transition metal dichalcogenides, and Weyl pairs in monolayer graphene sheets.

    hep-phEPJC(2024)·17 citations
14. 14*

    Magnetic field effect on hadron yield ratios and fluctuations in a hadron resonance gas

    Volodymyr Vovchenko🇺🇸

    This work studies the influence of an external magnetic field on hadron yields and fluctuations in a hadron resonance gas by performing calculations within an updated version of the open-source Thermal-FIST package. The presence of the magnetic field has a sizable influence on certain hadron yield ratios. Most notably, it leads to enhanced $p/\pi$ and suppressed $n/p$ ratios, which may serve as a magnetometer in heavy-ion collisions. By attributing the centrality dependence of the $p/\pi$ ratio in Pb-Pb collisions at 5.02~TeV measured by the ALICE Collaboration entirely to the magnetic field, its maximal strength at freeze-out is estimated to be $eB\simeq 0.12$~GeV${}^2\simeq 6.3m_{\pi }^2$ in peripheral collisions. The magnetic field also enhances various conserved charge susceptibilities, which is qualitatively consistent with recent lattice QCD data and is driven in the HRG model by the increase of hadron densities. However, the variances of hadrons do not show any enhancement when normalized by the means, therefore, measurements of second-order fluctuations in heavy-ion collisions appear to offer limited additional information about the magnetic field relative to mean multiplicities.

    hep-phnucl-thPRC(2024)·21 citations
15. 15*

    Nuclear deformation effects in photoproduction of $\rho$ mesons in ultraperipheral isobaric collisions

    Shuo Lin🇨🇳 · Jin-Yu Hu🇨🇳 · Hao-Jie Xu🇨🇳 · Shi Pu🇨🇳 · Qun Wang🇨🇳

    We have investigated the ${\rho }^0$ meson photoproduction in ultraperipheral isobaric collisions between ${}_{44}^{96}\text{Ru}{+}_{44}^{96}\text{Ru}$ and ${}_{40}^{96}\text{Zr}{+}_{40}^{96}\text{Zr}$ at $\sqrt{s_{NN}}=200$ GeV, employing the dipole model with the equivalent photon approximation. By implementing the Woods-Saxon distribution to represent the nuclear mass density, which is derived from density functional theory with an inclusion of nuclear deformation effects, we have calculated the transverse momentum $q_T$ spectra in isobaric collisions. We observe the characteristic dip behavior in these spectra, indicative of diffraction phenomena in high-energy physics. We notice that the deformation effects cause a nearly linear increase with $q_T^2$ for $q_T^2\lesssim 0.015$ ${\text{GeV}}^2$, aligning with experimental observations. We offer a simple explanation for the observed behavior in these spectra by introducing the effective width of the nuclei in the thickness function. We also extend our discussion on the ${\rho }^0$ meson photoproduction with the targets ${}^{63}\text{Cu}$,${}^{197}\text{Au}$, and ${}^{238}\text{U}$.

    hep-phnucl-thPRD(2025)·12 citations
16. 16*

    Boosting probes of CP violation in the top Yukawa coupling with Deep Learning

    Waleed Esmail🇩🇪 · A. Hammad🇯🇵 · Adil Jueid🇰🇷 · Stefano Moretti🇬🇧

    The precise measurement of the top-Higgs coupling is crucial in particle physics, offering insights into potential new physics Beyond the Standard Model (BSM) carrying {\cal CP} Violation (CPV) effects. In this paper, we explore the {\cal CP} properties of a Higgs boson coupling with a top quark pair, focusing on events where the Higgs state decays into a pair of $b$-quarks and the top-antitop system decays leptonically. The novelty of our analysis resides in the exploitation of two conditional Deep Learning (DL) networks: a Multi-Layer Perceptron (MLP) and a Graph Convolution Network (GCN). These models are trained for selected CPV phase values and then used to interpolate all possible values ranging from $0$ to $\pi /2$. This enables a comprehensive assessment of sensitivity across all {\cal CP} phase values, thereby streamlining the process as the models are trained only once. Notably, the conditional GCN exhibits superior performance over the conditional MLP, owing to the nature of graph-based Neural Network (NN) structures. Specifically, for Higgs top coupling modifier set to 1, with $\sqrt{s}=13.6$ TeV and integrated luminosity of $3$ ab${}^{-1}$ GCN excludes the {\cal CP} phase larger than $5^{\circ }$ at $95.4\%$ Confidence Level (C.L). Our Machine Learning (ML) informed findings indicate that assessment of the {\cal CP} properties of the Higgs coupling to the $t\bar{t}$ pair can be within reach of the High Luminosity Large Hadron Collider (HL-LHC), quantitatively surpassing the sensitivity of more traditional approaches.

    hep-phhep-exJHEP(2025)·14 citations
17. 17*

    Entanglement and Bell inequality violation in vector diboson systems produced in decays of spin-0 particles

    Alexander Bernal🇪🇸 · Paweł Caban🇵🇱 · Jakub Rembieliński🇵🇱

    We discuss entanglement and the violation of the CGLMP inequality in a system of two vector bosons produced in the decay of a spin-0 particle. We assume the most general CPT conserving, Lorentz-invariant coupling of the spin-0 particle with the daughter bosons. We compute the most general two-boson density matrix obtained by averaging over kinematical configurations with an appropriate probability distribution (which can be obtained when both bosons subsequently decay into fermion-antifermion). We show that the two-boson state is entangled and violates the CGLMP inequality for all values of the (anomalous) coupling constants and that in this case the state is entangled iff it can violate the CGLMP inequality. As an exemplary process of this kind we use the decay $H\to ZZ$ with anomalous coupling.

    hep-phhep-thquant-phSci.Rep.(2025)·40 citations
18. 18*

    The Phase Space Distance Between Collider Events

    Tianji Cai🇺🇸 · Junyi Cheng🇺🇸 · Nathaniel Craig🇺🇸 · Giacomo Koszegi🇺🇸 · Andrew J. Larkoski🇺🇸

    How can one fully harness the power of physics encoded in relativistic $N$-body phase space? Topologically, phase space is isomorphic to the product space of a simplex and a hypersphere and can be equipped with explicit coordinates and a Riemannian metric. This natural structure that scaffolds the space on which all collider physics events live opens up new directions for machine learning applications and implementation. Here we present a detailed construction of the phase space manifold and its differential line element, identifying particle ordering prescriptions that ensure that the metric satisfies necessary properties. We apply the phase space metric to several binary classification tasks, including discrimination of high-multiplicity resonance decays or boosted hadronic decays of electroweak bosons from QCD processes, and demonstrate powerful performance on simulated data. Our work demonstrates the many benefits of promoting phase space from merely a background on which calculations take place to being geometrically entwined with a theory's dynamics.

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

    X(3872) revisited: the roles of OPEP and the quark degrees of freedom

    Sachiko Takeuchi🇯🇵 · Yasuhiro Yamaguchi🇯🇵 · Atsushi Hosaka🇯🇵 · Makoto Takizawa🇯🇵

    The $X(3872)$ is investigated by employing the quark-hadron hybrid model, that consists of the $c\bar{c}$ core, $D^{(\ast )}\bar{D}{}^{\ast }$, $J/\psi \omega$, and $J/\psi \rho$ two-meson states. Due to the attraction from the $c\bar{c}$-$D\bar{D}{}^{\ast }$ coupling and from the OPEP tensor coupling, a very thin peak can appear at the $D^0\bar{D}{}^{\ast 0}$ threshold. The energy of the corresponding pole of the scattering matrix is $E=(+0.06-0.14i)$ MeV, which is on the physical sheet and above the threshold, the same as the one of the poles from the LHCb data analysis.

    hep-phFew Body Syst.(2021)·4 citations
20. 20*

    The neutrino force in neutrino backgrounds: Spin dependence and parity-violating effects

    Mitrajyoti Ghosh🇺🇸 · Yuval Grossman🇺🇸 · Walter Tangarife🇺🇸 · Xun-Jie Xu🇨🇳 · Bingrong Yu🇺🇸

    The neutrino force results from the exchange of a pair of neutrinos. A neutrino background can significantly influence this force. In this work, we present a comprehensive calculation of the neutrino force in various neutrino backgrounds with spin dependence taken into account. In particular, we calculate the spin-independent and spin-dependent parity-conserving neutrino forces, in addition to the spin-dependent parity-violating neutrino forces with and without the presence of a neutrino background for both isotropic and anisotropic backgrounds. Compared with the vacuum case, the neutrino background can effectively violate Lorentz invariance and lead to additional parity-violating terms that are not suppressed by the velocity of external particles. We estimate the magnitude of the effect of atomic parity-violation experiments, and it turns out to be well below the current experimental sensitivity.

    hep-phastro-ph.COhep-exJHEP(2024)·14 citations
21. 21*

    Complementary Search of Fermionic Absorption Operators at Hadron Collider and Direct Detection Experiments

    Kai Ma🇨🇳 · Shao-Feng Ge🇨🇳 · Lin-Yun He🇨🇳 · Ning Zhou🇨🇳

    Instead of the energy recoil signal at direct detection experiments, dark fermion appears as missing energy at hadron colliders. For a fermionc dark sector particle that coupled with quarks and neutrino via absorption operators, its production at collider is accompanied by an invisible neutrino. We study in details the mono-$X$ (photon, jet, and $Z$) productions at the Large Hadron Collider (LHC). We start from the quark-level absorption operators to make easy comparison between the collider and direct detection experiments. In other words, we study the model-independent constraints on a dark fermion with absorption operator. In addition, the interplay and comparison with the possible detection at the neutrino experiments, especially Borexino, is also briefly discussed. We find that light nuclear target can provide the stronger constraints on both spin-dependent and spin-independent absorption operators.

    hep-phhep-exPRD(2026)·6 citations
22. 22*

    Exploring the Dark Sector of the inspired FNSM at the LHC

    Amit Chakraborty🇮🇳 · Dilip Kumar Ghosh🇮🇳 · Najimuddin Khan🇮🇳 · Stefano Moretti🇬🇧

    We establish the possibility of having a pseudo-Nambu-Goldstone boson (pNGB) Dark Matter (DM) candidate in the inspired Froggatt-Nielsen Singlet Model (iFNSM) wherein a direct connection exists between the DM mass and new flavon symmetry-breaking scale. We find a considerable allowed region of parameter space for the ensuing pseudoscalar DM, which is dependent upon the flavon Vacuum Expectation Value (VEV) and Yukawa couplings, over which it may be possible to explain the fermion mass hierarchy. Finally, we choose a Benchmark Point (BP) and perform detailed collider analyses to probe this DM state in the context of Run 3 of the Large Hadron Collider (LHC). Specifically, in this model, one obtains large missing transverse energy ($\text{slashed}{E}_T$) when the DM particle is resonantly produced from the decay of a heavy Higgs field, along with multiple jets from Initial State Radiation (ISR). Thus, the ensuing $\text{slashed}{E}_T$ + $n\mathrm{jets}(n\ge 1)$ signature is an excellent probe of DM in this construct.

    hep-phNPB(2026)·3 citations
23. 23*

    Electron form factors in Basis Light-front Quantization

    Lingdi Meng🇨🇳 · Shuo Tang🇺🇸 · Zhi Hu🇯🇵 · Guo-Li Wang🇨🇳 · Yang Li🇨🇳 · Xingbo Zhao🇨🇳 · James P. Vary🇺🇸

    In this paper, we evaluate the electromagnetic and gravitational form factors as well as the corresponding generalized parton distributions of the electron using the Basis Light-front Quantization approach to QED. We compare our results with those from light-front perturbation theory. We adopt a novel basis with its scale depending on the constituents' longitudinal momentum fraction. We show that this basis improves convergence of the form factors with increasing basis dimension, compared to that calculated in the original basis with fixed scale. These results both validate the BLFQ approach and provide guidance for its efficient implementation in solving light-front Hamiltonian mass eigenstates for more complex systems in QED and QCD.

    hep-phnucl-th2 citations
24. 24*

    Apparent fake neutrino mixture due to seesaw mechanism responsible for oscillation

    Xiao-Yan Wang🇨🇳

    This paper assumes that neutrino flavor conversion is induced by right-handed neutrino mixture via seesaw mechanism, which leads to apparent fake neutrino mixture with neutrino mass eigenstate consistent with flavor state of left-handed neutrino rather than mixture of flavor state. The transition probability between right-handed neutrinos due to mixture can be explained well by boson intermediating flavor flip interaction between right-handed neutrinos and neutrino oscillation can be considered macro phenomenon before all flavor flip interactions arrive at balance.

    hep-ph0 citations
25. 25*

    Next-to-Next-to-Leading Order Evolution of Polarized Parton Densities in the Larin Scheme

    J. Blümlein🇩🇪 · M. Saragnese🇩🇪

    In many calculations involving polarized twist-2 parton densities to higher order in the strong coupling constant one uses the Larin scheme to describe chiral effects in dimensional regularization. Upon forming observables, the scheme dependence cancels. Still one needs a corresponding regularization scheme to compute the contributing building blocks, like massless and massive Wilson coefficients, as well as the massive 3-loop operator matrix elements used in the variable flavor number scheme. These are matched to the evolved parton distribution functions in the Larin scheme. Starting with suitable input distributions we provide the solution of scale evolution of the different polarized parton distribution functions in Bjorken $x$ space for a wide range of virtualities $Q^2$ in the Larin scheme, at next-to-leading, and to next-to-next-to-leading order for the first time. We also illustrate the deviation between the parton distributions in the Larin and $\overline{\mathrm{MS}}$ schemes numerically.

    hep-phPRD(2024)·10 citations
26. 26*

    Gravity induced CP violation

    J-M Rax🇫🇷

    The impact of earth's gravity on neutral kaons oscillations is analyzed. The main effect of a Newtonian potential is to couple the strangeness oscillation and the strange quarks zitterbewegung. This coupling is responsible for the observed CP violations. Gravity induced CP violation is in fact a CPT violation with T conservation rather than a T violation with CPT conservation, but the finite lifetime of the short-lived kaons induces a rotation of the imaginary CPT parameter such that it becomes real and the effect is observed as a CP and T violation. Both indirect and direct violation parameters are predicted in agreement with the experimental data.

    hep-ph2 citations
27. 27*

    Searching for signatures of new physics in $B\to K\nu \overline{\nu }$ to distinguish between Dirac and Majorana neutrinos

    C. S. Kim🇰🇷 · Dibyakrupa Sahoo🇵🇱 · K. N. Vishnudath🇨🇱

    We conduct a model-independent analysis of the distinct signatures of various generic new physics possibilities in the decay $B\to K\nu \overline{\nu }$ by analyzing the branching ratio as well as the missing mass-square distribution. Considering the final neutrinos to be of the same flavor with non-zero mass, we discuss the new physics contributions for both Dirac and Majorana neutrino possibilities. In our study, we utilize the analytical relations among form factors in semi-leptonic $B\to K$ transitions, which are consistent with current lattice QCD predictions to a very high numerical accuracy. We provide constraints on different new physics parameters, taking into account the recent measurement of $B^{+}\to K^{+}\nu \overline{\nu }$ branching ratio by the Belle-II collaboration. In future, if the missing mass-square distribution for $B^{+}\to K^{+}\nu \overline{\nu }$ decay gets reported by Belle-II with analysis of more events than their present data set, one can not only investigate possible new physics effects in these decays, but also probe the Dirac/Majorana nature of the neutrinos using quantum statistics, since a difference between the two cases is known to exist in the presence of non-standard neutrino interactions.

    hep-phEPJC(2024)·22 citations
28. 28*

    QCD predictions for vector boson plus hadron production at the LHC

    Simone Caletti🇨🇭 · Aude Gehrmann-De Ridder🇨🇭 · Alexander Huss🇨🇭 · Adrian Rodriguez Garcia🇨🇭 · Giovanni Stagnitto🇮🇹

    The identification of a hadron in the final state of hadron-collider events that feature a leptonically decaying vector boson can provide essential information on the parton content of the colliding protons. Moreover, the study of hadrons inside jets can provide deeper insights into the fragmentation dynamics. We provide theoretical predictions for specific observables involving either the production of a $Z$ boson in association with light charged hadrons inside a jet or the production of a $W$ boson together with a charmed hadron. We present results for various fragmentation functions and compare our predictions with measurements by LHCb and ATLAS at $\sqrt{s}=13$ TeV. Our predictions are obtained using the antenna subtraction formalism which has been extended to cope with infrared singularities associated to the fragmentation processes in a hadron-collider environment at NLO accuracy.

    hep-phJHEP(2024)·14 citations
29. 29*

    Adiabatic Hydrodynamization and the Emergence of Attractors: a Unified Description of Hydrodynamization in Kinetic Theory

    Krishna Rajagopal🇺🇸 · Bruno Scheihing-Hitschfeld🇺🇸 · Rachel Steinhorst🇺🇸

    "Attractor" solutions for the pre-hydrodynamic, far-from-equilibrium, evolution of the matter produced in relativistic heavy ion collisions have emerged as crucial descriptors of the rapid hydrodynamization of quark-gluon plasma (QGP). Adiabatic Hydrodynamization (AH) has been proposed as a framework with which to describe, explain, and predict attractor behavior that draws upon an analogy to the adiabatic approximation in quantum mechanics. In this work, we systematize the description of pre-hydrodynamic attractors in kinetic theory by showing how to use the AH framework to identify these long-lived solutions to which varied initial conditions rapidly evolve, demonstrating the robustness of this framework. In a simplified QCD kinetic theory in the small-angle scattering limit, we use AH to explain both the early- and late-time scaling behavior of a longitudinally expanding gluon gas in a unified framework. In this context, we show that AH provides a unified description of, and intuition for, all the stages of what in QCD would be bottom-up thermalization, starting from a pre-hydrodynamic attractor and ending with hydrodynamization. We additionally discuss the connection between the notions of scaling behavior and adiabaticity and the crucial role of time-dependent coordinate redefinitions in identifying the degrees of freedom of kinetic theories that give rise to attractor solutions. The tools we present open a path to the intuitive explanation of how attractor behavior arises and how the attractor evolves in all stages of the hydrodynamization of QGP in heavy ion collisions.

    hep-phnucl-thJHEP(2025)·16 citations
30. 30*

    Resonant or asymmetric: The status of sub-GeV dark matter

    Sowmiya Balan🇩🇪 · Csaba Balázs🇦🇺 · Torsten Bringmann🇳🇴 · Christopher Cappiello🇨🇦 · Riccardo Catena🇸🇪 · Timon Emken🇸🇪 · Tomás E. Gonzalo🇩🇪 · Taylor R. Gray🇸🇪 · Will Handley🇬🇧 · Quan Huynh🇦🇺 · Felix Kahlhoefer🇩🇪 · Aaron C. Vincent🇨🇦

    Sub-GeV dark matter (DM) particles produced via thermal freeze-out evade many of the strong constraints on heavier DM candidates but at the same time face a multitude of new constraints from laboratory experiments, astrophysical observations and cosmological data. In this work we combine all of these constraints in order to perform frequentist and Bayesian global analyses of fermionic and scalar sub-GeV DM coupled to a dark photon with kinetic mixing. For fermionic DM, we find viable parameter regions close to the dark photon resonance, which expand significantly when including a particle-antiparticle asymmetry. For scalar DM, the velocity-dependent annihilation cross section evades the strongest constraints even in the symmetric case. Using Bayesian model comparison, we show that both asymmetric fermionic DM and symmetric scalar DM are preferred over symmetric fermionic DM due to the reduced fine-tuning penalty. Finally, we explore the discovery prospects of near-future experiments both in the full parameter space and for specific benchmark points. We find that the most commonly used benchmark scenarios are already in tension with existing constraints and propose a new benchmark point that can be targeted with future searches.

    hep-phastro-ph.COJCAP(2025)·55 citations
31. 31*

    Explicit estimate of charm rescattering in $B^0\to K^0\bar{\ell }\ell$

    Gino Isidori🇨🇭 · Zachary Polonsky🇨🇭 · Arianna Tinari🇨🇭

    We analyze $B^0\to K^0\bar{\ell }\ell$ long-distance contributions induced by the rescattering of a pair of charmed and charmed-strange mesons. We present an explicit estimate of these contributions using an effective description in terms of hadronic degrees of freedom, supplemented by data on the $B^0\to D^{\ast }{D}_s(D_s^{\ast }D)$ transition in order to reproduce the corresponding discontinuity in the $B^0\to K^0\bar{\ell }\ell$ amplitude. The $D^{\ast }{D}_s(D_s^{\ast }D)K$ vertex is estimated using heavy-hadron chiral perturbation theory, obtaining an accurate description of the whole rescattering process in the low-recoil (or high-$q^2$) limit. We also present an extrapolation to the whole kinematical region introducing hadronic form factors. The explicit estimate of the leading $D^{\ast }{D}_s(D_s^{\ast }D)$ intermediate state leads to a long-distance amplitude which does not exceed a few percent relative to the short-distance one. The consequences of this result for the extraction of the short-distance coefficient $C_9$ are discussed.

    hep-phPRD(2025)·46 citations
32. 32*

    New realisation of light thermal dark matter with enhanced detection prospects

    Amit Adhikary🇫🇷 · Debasish Borah🇮🇳 · Satyabrata Mahapatra🇰🇷 · Indrajit Saha🇮🇳 · Narendra Sahu🇮🇳 · Vicky Singh Thounaojam🇮🇳

    Light dark matter (DM) with mass around the GeV scale faces weaker bounds from direct detection experiments. If DM couples strongly to a light mediator, it is possible to have observable direct detection rate. However, this also leads to a thermally under-abundant DM relic due to efficient annihilation into light mediators. We propose a novel scenario where a first-order phase transition (FOPT) occurring at MeV scale can restore GeV scale DM relic by changing the mediator mass sharply at the nucleation temperature. The MeV scale FOPT predicts stochastic gravitational waves with nano-Hz frequencies within reach of pulsar timing array (PTA) based experiments like NANOGrav. In addition to enhancing direct detection rate, the light mediator can also give rise to the required DM self-interactions necessary to solve the small scale structure issues of cold dark matter. The existence of light scalar mediator and its mixing with the Higgs keep the scenario verifiable at different particle physics experiments.

    hep-phastro-ph.COJCAP(2024)·12 citations
33. 33*

    Dual Inflation and Bounce Cosmologies Interpretation of Pulsar Timing Array Data

    Changhong Li🇨🇳 · Junrong Lai🇨🇳 · Jinjie Xiang🇨🇳 · Chaofan Wu🇨🇳

    We explore a dual scenario of generalized inflation and bounce cosmologies, producing a scale-invariant curvature perturbation spectrum. Bayesian analysis with pulsar timing array data identifies, for the first time, viable regions from inflation and bounce that simultaneously explain stochastic gravitational wave background (SGWB) signals and CMB anisotropies. Bayes factor calculations strongly favor this dual scenario over conventional sources and provide initial evidence of a duality between inflation and bounce regarding SGWB, offering new insights for early universe model-building and future observations.

    ↳ astro-ph.COgr-qchep-phJHEP(2024)·9 citations
34. 34*

    Vavilov-Cherenkov radiation for parallel motion in three-dimensional topological insulators

    O. J. Franca🇩🇪 · Stefan Yoshi Buhmann🇩🇪

    Our study delves into the modifications observed in Vavilov-Cherenkov radiation when its generating charged particle moves parallel to an interface formed by two generic magnetoelectric media, focusing on topological insulators. We compute the electromagnetic field through the Green's function. Applying the far-field approximation and the steepest descent method, we derive analytical expressions for the electric field, revealing contributions from spherical and lateral waves with topological origins. Subsequently, we analyze the angular distribution of the radiation, particularly focusing on parallel motions in close proximity to the interface. Our findings indicate that the radiation along the Vavilov-Cherenkov cone is inhomogeneous and asymmetric. We analyze the radiated energy at both sides of the interface. Finally, we discuss the particle's retarding force, which is notably enhanced in the ultrarelativistic regime. We illustrate these results for the topological insulator TlBiSe${}_2$ and the magnetoelectric TbPO${}_4$.

    ↳ cond-mat.mes-hallhep-phhep-thPRB(2024)·5 citations
35. 35*

    Charm physics at the Belle and Belle II experiments

    Longke Li🇺🇸

    We present recent results on charm physics at the Belle and Belle II experiments, covering measurements of charm lifetimes, branching fractions of the decays of charmed mesons and baryons and the decay asymmetry parameters of two-body decays of charmed baryons, searches for rare and forbidden decays, and measurements of $CP$ violating parameters in the four-body decays of charmed mesons and two-body decays of charmed baryons.

    ↳ hep-exhep-ph0 citations
36. 36*

    Localization of $q$-form field on squared curvature gravity domain wall brane coupling with gravity and background scalar

    Xin-Nuo Zhang🇨🇳 · Heng Guo🇨🇳 · Yong-Tao Lu🇨🇳

    Unlike the duality in four-dimensional spacetime, where the $q-$form fields corresponds to the scalar fields or the vector fields, in higher dimensional spacetime, they denote new types of particles. In this paper, we investigate the localization of the KK modes of the $q$-form fields in a five dimensional brane world. We introduce the coupling between the $q-$form fields and both the gravity and the background scalar field. This consideration enables the localization of the $q$-form fields on the five-dimensional RS-2 thick brane, leading to the derivation of zero modes, Schrödinger-like equations, and a four-dimensional effective action. We suggest a new function $F(R,\phi )$ to stand for the coupling of the $q$-form field with gravity and background scalar fields. Our analysis highlights the significance of the parameters ${\text{C}}_2$ and $t$ in the localization processes.

    ↳ hep-thgr-qchep-phEPJC(2025)·0 citations
37. 37*

    Monte-Carlo Study Of Higher-Order Cumulants of Net-Particle Distributions in $p+p$ Collisions at $\sqrt{s}$ = 13 TeV

    Abdussamad M🇮🇳 · Rahul Verma🇮🇳 · Nirbhay Kumar Behera🇮🇳 · Sadhana Dash🇮🇳 · Basanta Kumar Nandi🇮🇳

    Measurement of higher order cumulants of the distributions of conserved quantities, like net-charge, net-baryon and net-strangeness in heavy-ion collisions, is proposed as a sensitive tool to determine the freeze-out parameters and the nature of phase transitions at the LHC energies. Baseline measurements for heavy-ion collisions are essential to understand the experimental measurements. Recently, several experimental observations have shown some QGP-like scenarios in small systems (pp collisions). We report the first Monte-Carlo study of the measurements of cumulants and their ratios for net-charge, net-hadron, net-kaon, net-baryon, and net-proton distributions in pp collisions at $\sqrt{s}$=13 TeV using pQCD models like Pythia8 and Herwig. We also discuss the effect of different particle production mechanisms on the higher-order cumulants. This simulation study will serve as a baseline for future measurements at the LHC. Furthermore, it will shed more light on the measurement of cumulants and the connection between small systems and heavy-ion collisions at the LHC.

    ↳ nucl-exhep-exhep-phPRC(2025)·0 citations
38. 38*

    Four-nucleon clustering near the QCD critical point: theory versus experiment

    Edward Shuryak🇺🇸

    This letter relates theoretical predictions made previously with recently announced RHIC BES-II experimental data on multi-baryon fluctuations. We conclude that new statistically significant effect is observed, and its features are in good agreement with predictions.

    ↳ nucl-thhep-ph2 citations
39. 39*

    Bounding the Cosmological Constant using Galactic Rotation Curves from the SPARC Dataset

    David Benisty🇩🇪 · David Vasak🇩🇪 · Jürgen Struckmeier🇩🇪 · Horst Stöcker🇩🇪

    Dark energy (and its simplest model, the Cosmological Constant or $\Lambda$) acts as a repulsive force that opposes gravitational attraction. Assuming galaxies maintain a steady state over extended periods, the estimated upper limit on $\Lambda$ studies its pushback to the attractive gravitational force of dark matter. From the SPARC dataset, we select galaxies that are best fitted by the Navarro-Frenk-White (NFW) and Hernquist density models. Introducing the presence of $\Lambda$ in these galaxies helps to establish the upper limit on its repulsive force. This upper limit on $\Lambda$ is around ${\rho }_{\left(<\Lambda \right)}\sim 10^{-25}$~kg/m${}^3$, only two orders of magnitude higher than the one measured by Planck. {We show that for galaxies with detectable velocities far from the galaxy core, the upper limit on $\Lambda$ is lower. Furthermore, we show that galaxies and other systems follow the same principle: for larger orbital periods the upper limit on $\Lambda$ is lower. Consequently, we address the implications for future measurements on the upper limit and the condition for detecting the impact of $\Lambda$ on galactic scales.

    ↳ astro-ph.COastro-ph.GAgr-qchep-ph+1PRD(2024)·7 citations
40. 40*

    Thin-wall vacuum decay in the presence of a compact dimension

    Ignatios Antoniadis🇹🇭 · Daniele Bielli🇹🇭 · Auttakit Chatrabhuti🇹🇭 · Hiroshi Isono🇹🇭

    We study the problem of false vacuum decay in arbitrary dimensions, in the presence of gravity, and compute the transition probability within the thin-wall approximation, generalising the results of Coleman and de Luccia. In the particular case of one compact dimension, we present explicit formulae for the Euclidean Bounce configuration that drives the transition from a de Sitter to Minkowski or from a Minkowski to anti-de Sitter vacua.

    ↳ hep-thgr-qchep-phJHEP(2024)·5 citations
41. 41*

    Jet substructure measurements in heavy-ion collisions

    Robert Vertesi (for the ATLAS, CMS, and ALICE Collaborations)🇭🇺

    Jet substructure in heavy-ion collisions is a rapidly evolving area with lots of intriguing new measurements. This contribution presents a selection of recent jet-substructure measurements from experiments at the LHC, in particular, soft-drop groomed radii of jets and reclustered large-radius jets from ATLAS, jet axis difference and generalized jet angularities from ALICE, as well as dijet shapes and b-jet shapes from the CMS experiment.

    ↳ nucl-exhep-phnucl-thInt.J.Mod.Phys.A(2025)·5 citations
42. 42*

    An alternative method for searching for dimuon displaced vertices in the short-range region with ATLAS and CMS

    Attilio Santocchia🇮🇹

    Search for BSM phenomena is one of the fundamental goals of the LHC experiments. Many BSM models foresee long-lived particles which decay far from the production vertex and a big effort has been done both by the ATLAS and CMS collaborations to detect these long-lived particles. A specific, widely studied, example for such searches is made through the measurement of displaced vertices produced by a narrow resonance decaying to a muon pair. This paper will first analyze what has been done so far and will try to evaluate if there are improvements which may allow enhancing the discovery potential at LHC for such particles. The outcome of this work is that while long-lived particles decaying more than 1 cm from the primary vertex have been carefully studied by ATLAS and CMS, the region within a few millimeters from the primary vertex may have been partially neglected. A new approach for searching such resonances, fully based on data, will then be proposed which allows minimizing systematic uncertainties while keeping at a maximum the discovery potentiality for long-lived neutral resonances which decay a few millimeters from the primary vertex.

    ↳ hep-exhep-phPLB(2025)·2 citations
43. 43*

    Ultraheavy Ultrahigh-Energy Cosmic Rays

    B. Theodore Zhang🇯🇵 · Kohta Murase🇺🇸 · Nick Ekanger🇺🇸 · Mukul Bhattacharya🇺🇸 · Shunsaku Horiuchi🇺🇸

    We investigate the propagation of ultraheavy (UH) nuclei as ultrahigh-energy cosmic rays (UHECRs). We show that their energy loss lengths at $\lesssim 300$ EeV are significantly longer than those of protons and intermediate-mass nuclei, and that the highest-energy cosmic rays with energies beyond $\sim 100$ EeV, including the Amaterasu particle, may be UH-UHECRs. For the first time, we derive constraints on the contribution of UH-UHECR sources, and find that the current data are consistent with energy generation rate densities of UHECRs from collapsars and neutron star mergers. Our model predicts that the mean value of the depth of shower maximum is lower than that for iron nuclei beyond 100 EeV, which can be tested with future composition measurements, e.g., AugerPrime and the Global Cosmic Ray Observatory. In addition, the spectral tension between the Telescope Array (TA) and the Pierre Auger Observatory can be alleviated by considering the enhanced contribution of UHECRs -- including UH nuclei -- from a nearby transient.

    ↳ astro-ph.HEhep-phnucl-thPRL(2026)·39 citations
44. 44*

    A universal constraint on axion non-Abelian dynamics during inflation

    Ema Dimastrogiovanni🇳🇱 · Matteo Fasiello🇪🇸 · Martino Michelotti🇳🇱 · Ogan Özsoy🇪🇸

    Inflationary models equipped with Chern-Simons coupling between their axion and gauge sectors exhibit an array of interesting signals including a testable chiral gravitational wave spectrum. The energy injection in the gauge sector triggered by the rolling axion leads to a well-studied enhancement of gauge field fluctuations. These may in turn affect observables such as the scalar and tensor spectra and also account for non-linear corrections to field propagators. In this work, we focus on non-Abelian gauge sectors. We show that gauge field self-interactions and axion-gauge field non-linear couplings significantly renormalize the gauge field mode function. Operating within the regime of validity of the perturbative treatment places strong constraints on the accessible parameter space of this class of models. We calculate corrections to the gauge field propagator that are universally present in these scenarios. Enforcing perturbativity on such propagators leads to bounds that are competitive with those stemming from analytical estimates on the onset of the strong backreaction regime.

    ↳ astro-ph.COgr-qchep-phhep-thJCAP(2025)·14 citations
45. 45*

    A black hole effective theory for strongly interacting matter

    Matti Jarvinen🇰🇷 · Dorin Weissman🇰🇷

    We establish a new tool for studying strongly coupled matter: an effective theory of black holes in gravity, which maps to a hydrodynamic description of field theories via the gauge-gravity duality. Our approach is inspired by previously known effective theories found in the limit of high number of dimensions. We argue that the new approach can accurately describe phase transitions in a wide class of theories, such as the Yang-Mills and other nearly critical field theories. As an application, we analyze the interface between confining and deconfining phases in holographic Yang-Mills theory.

    ↳ hep-thgr-qchep-phPRD(2025)·3 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.