Tue·Aug 27, 2024Tuesday·August 27, 2024

1. 01*

   Search for Stochastic GW Signal as a Complementary Approach to Multi-Higgs Productions at the Hadron Colliders to Probe Dimension Six Operator

   Dilruba Gazi🇮🇳 · Abhi Mukherjee🇮🇳 · Saurabh Niyogi🇮🇳 · Sujoy Poddar🇮🇳

   We have considered an effective field theory framework in which the Standard Model is extended by a non-renormalizable dimension six operator ($\frac{1}{{\Lambda }^2}(H^{†}H{)}^3$) respecting the symmetries of the Standard Model. Such an operator can affect the dynamics of Higgs field and the electroweak phase transition. Presence of such term modifies the triple Higgs coupling which is already under the lens from di-Higgs searches in various channels at the LHC. Constraint on the scale parameter $\Lambda$ is obtained from the di-Higgs data at the LHC Run II. Additionally, such dimension six terms will give rise to additional couplings which will affect tri-Higgs and four-Higgs productions at future high energy, high luminosity hadron colliders. The shape of the scalar potential also gets modified due to such higher dimensional term composed of Higgs field. It is worthwhile to study the impact of such higher-dimensional operators at suitable gravitational wave (GW) interferometry experiments since GW astronomy has become a good probe for new physics searches. Bounds obtained on the scale parameter $\Lambda$ from the allowed first-order electroweak phase transition is $450\lesssim \Lambda \lesssim 590$~GeV. On the other hand, di-Higgs results from the LHC Run II put a lower bound on $\Lambda \gtrsim 340$~GeV.

   hep-phhep-ex5 citations
2. 02*

   Evidence of Dark Energy Prior to its Discovery

   Geoffrey W. Marcy🇰🇷

   This is a review and statistical analysis of the evidence supporting the existence of a cosmological constant in the early 1990s, before its discovery made with distant supernovae in 1998. The earlier evidence was derived from newly precise measurements of the Universe, including its mass density, the Hubble constant, the age of the oldest stars, the filamentary large-scale structure, and the anisotropy of the cosmic microwave background. These measurements created tension for models assuming the cosmological constant was zero. This tension was alleviated by several insightful papers published before 1996, which proposed a cosmological constant that increased the expansion rate. Statistical analysis here shows that the probability of the cosmological constant being zero was demonstrably less than a few percent. Some models identified a best-fit value close to the modern estimate of Omega_Lambda ~ 0.7.

   hep-phastro-ph.COphysics.hist-ph2 citations
3. 03*

   Power corrections to quasi-distribution amplitudes of a heavy meson

   Chao Han🇨🇳 · Wei Wang🇨🇳 · Jia-Lu Zhang🇨🇳 · Jian-Hui Zhang🇨🇳

   It has been recently demonstrated that lightcone distribution amplitudes (LCDAs) for a heavy meson, defined in the heavy quark limit, can be extracted by simulating quasi-distribution amplitudes on the lattice with a large meson momentum $P^z$. This extraction involves a two-step procedure. In the first-step, the quasi-distribution amplitudes are matched onto the QCD LCDAs in the large $P^z$ limit. In the second step, the QCD LCDAs are matched onto the desired LCDAs defined in HQET. In this work, we present the $m_H^{2n}/(P^z{)}^{2n}$ and ${\Lambda }_{\text{QCD}}^2/(P^z{)}^2$ corrections in the first step with $m_H$ being the heavy meson mass. To account for $m_H^{2n}/(P^z{)}^{2n}$ corrections, we employ two methods: the moment relation that can provide mass corrections to all orders, and a leading-twist projector that gives the leading-order mass corrections. For the ${\Lambda }_{\text{QCD}}^2/(P^z{)}^2$ corrections, we employ a renormalon model that addresses the renormalon ambiguity stemming from the divergence of the perturbative series. We adopt two parametrizations for QCD LCDAs to conduct a numerical analysis. The results suggest that these corrections are typically smaller than 20\% in most regions, and should be included in a precision analysis. These findings will serve as a valuable guide for future studies on heavy meson LCDAs, particularly in the context of Lattice QCD, where accounting for such corrections is crucial for improving the accuracy and reliability of the results.

   hep-phPRD(2024)·19 citations
4. 04*

   $\rho$ meson transverse momentum dependent parton distributions

   Jin-Li Zhang🇨🇳 · Jun Wu🇨🇳

   In this paper, the light-front wave functions (LFWFs) of $\rho$ meson are evaluated in the framework of Nambu--Jona-Lasinio model using the proper time regularization scheme. The transverse momentum dependent parton distributions (TMDs) of the $\rho$ meson are derived from the overlap representations of the LFWFs. We investigate the ${\mathbf{k}}_{\perp }$-weighted moments and the $x$-dependent average transverse momentum $⟨k_{\perp }^n(x){⟩}_{\alpha }$ of $\rho$ meson TMDs, $⟨k_{\perp }^n(x){⟩}_{\alpha }$ shows the typical transverse momenta of quark TMDs in our model. Our findings indicate that the average transverse momenta of $⟨k_{\perp }(x){⟩}_{\alpha }$ fall within the range of $[0.3,0.45]$ GeV, while $⟨k_{\perp }^2(x){⟩}_{\alpha }$ are in the region of $[0.15,0.30]$ GeV${}^2$. Our TMDs and parton distribution function (PDFs) exhibit excellent adherence to positive constraints. The investigation of spin densities within the $\rho$ meson in transverse momentum space reveals axially symmetric distributions for quarks and targets polarized in either longitudinal or transverse directions. Conversely, unpolarized symmetric distributions occur when the quark is longitudinally polarized and the target is transversely polarized, while exhibiting dipolar distortions in the opposite scenario. A comparison between TMDs from LFWFs and those from a covariant approach demonstrates that TMDs from LFWFs more effectively satisfy positive constraints than their counterparts from the covariant approach. Furthermore, the $x$-moments of $\rho$ meson PDFs indicate that $⟨x{⟩}_{g_L}$ is larger using LFWFs compared to the covariant approach.

   hep-phEPJC(2025)·9 citations
5. 05*

   Vacuum (in)stability in 2HDMS vs N2HDM

   Jayita Lahiri🇩🇪 · Gudrid Moortgat-Pick🇩🇪

   In this work, we examine the criteria for vacuum stability in two models with extended scalar sectors namely, the N2HDM and the 2HDMS and make a detailed comparison between the two. For the purpose of demonstration, we choose a scenario which can accommodate the recently observed 95 GeV excess in both models. We further explore the impact of the measurement of the Yukawa couplings, the gauge boson couplings and most importantly the trilinear self-couplings of the scalars, in distinguishing the vacuum structure in both models. We further investigate the constraints from vacuum stability on the 2HDMS scenario that accommodates a viable dark matter candidate and compare it with the N2HDM case.

   hep-ph3 citations
6. 06*

   Spin-dependent dark matter interactions at loop-level in Ar and Xe

   Nassim Bozorgnia🇨🇦 · Muping Chen🇺🇸 · Graciela B. Gelmini🇺🇸 · Alvine C. Kamaha🇺🇸 · Yongheng Xu🇺🇸

   Xenon and argon are the two noble gases used in tonne scale dark matter direct detection experiments. We compare the detection capability of both target elements for interactions due to a pseudoscalar mediator including loop-level contributions to the cross section. At tree-level this type of interaction depends on the nuclear spin and would thus not be detectable in argon-based detectors, since Ar has spin zero. However, at the loop-level the same interaction yields spin-independent contributions that would be detectable in an argon target and are not negligible with respect to the tree-level interactions in xenon, because these are momentum suppressed. In fact, the loop-level contributions are also important for xenon-based experiments at low recoil energies, which could change their discovery reach for this interaction.

   hep-phastro-ph.COJCAP(2025)·3 citations
7. 07*

   Study of the semileptonic decays ${\rm Y}(1S)\to B_{(c)}\ell {\bar{\nu }}_{\ell }$

   Chien-Thang Tran🇻🇳 · Mikhail A. Ivanov🇷🇺 · Pietro Santorelli🇮🇹 · Hai-Cat Tran🇻🇳

   We study the exclusive semileptonic decays ${\rm Y}(1S)\to B_{(c)}\ell {\bar{\nu }}_{\ell }$, where $\ell =e,\mu ,\tau$. The relevant hadronic form factors are calculated using the Covariant Confined Quark Model developed previously by our group. We predict the branching fractions $\mathcal{B}({\rm Y}(1S)\to B_{(c)}\ell {\bar{\nu }}_{\ell })$ to be of the order of $10^{-13}$ and $10^{-10}$ for the case of $B$ and $B_c$, respectively. Our predictions agree well with other theoretical calculations. We also consider the effects of possible New Physics in the case of ${\rm Y}(1S)\to B_c\tau {\bar{\nu }}_{\tau }$. We show that the branching fraction of this decay can be enhanced by an order of magnitude using constraints from the $B\to D^{(\ast )}\ell {\bar{\nu }}_{\ell }$ and $B_c\to J/\psi \ell {\bar{\nu }}_{\ell }$ experimental data.

   hep-phCPC(2025)·9 citations
8. 08*

   The ground states of hidden-charm tetraquarks and their radial excitations

   Guo-Liang Yu🇨🇳 · Zhen-Yu Li🇨🇳 · Zhi-Gang Wang🇨🇳 · Bin WU🇨🇳 · Ze Zhou🇨🇳 · Jie Lu🇨🇳

   Inspired by the great progress in the observations of charmonium-like states in recent years, we perform a systematic analysis about the ground states and the first radially excited states of $qc\bar{q}\bar{c}$ ($q$=$u/d$ and $s$) tetraquark systems. Their mass spectra, root mean square (r.m.s.) radii and radial density distributions are predicted within the framework of relativized quark model. By comparing with experimental data, some potential candidates for hidden-charm tetraquark states are suggested. For $qc\bar{q}\bar{c}$ ($q$=$u/d$) system, if $Z_c(3900)$ is supposed to be a compact tetraquark state with $J^{PC}=1^{+-}$, $Z(4430)$ can be interpreted as the first radially excited states of $Z_c(3900)$. Another broad structure $Z_c(4200)$ can also be explained as a partner of $Z_c(3900)$, and it arise from a higher state with $J^{PC}=1^{+-}$. In addition, theoretical predictions indicate that the possible assignments for $X(3930)$, $X(4050)$ and $X(4250)$ are low lying $0^{++}$ tetraquark states. As for the $sc\bar{s}\bar{c}$ system, $X(4140)$ and $X(4274)$ structures can be interpreted as this type of tetraquark states with $J^{PC}=1^{++}$, and $X(4350)$ can be described as a $sc\bar{s}\bar{c}$ tetraquark with $J^{PC}=0^{++}$. With regard to $qc\bar{s}\bar{c}$ ($q$=$u/d$) system, we find two potential candidates for this type of tetraquark, which are $Z_{cs}(4000)$ and $Z_{cs}(4220)$ structures. The measured masses of these two structures are in agreement with theoretical predictions for the $1^{+}$ state.

   hep-phEPJC(2024)·7 citations
9. 09*

   Theoretical results for top-pair and top+$W$ production

   Nikolaos Kidonakis🇺🇸

   I present theoretical results for top-pair production as well as for the associated production of top quarks with $W$ bosons. Soft-gluon corrections from resummation are calculated through approximate N${}^3$LO and added to fixed-order QCD results, and electroweak corrections are included at NLO. Top-quark transverse-momentum and rapidity distributions are also presented. In all cases the higher-order corrections are large, they reduce the scale dependence, and they improve agreement with recent data.

   hep-phPoS(2025)·2 citations
10. 10*

    Tetraquark nature of the $a_0(980)$ meson in hadronic $D$ decays

    Hai-Yang Cheng🇹🇼 · Cheng-Wei Chiang🇹🇼 · Fanrong Xu🇨🇳

    The internal structure of the light scalar meson $a_0(980)$ is explored in the three-body $D$ decays of $D\to a_0(980)P\to P_1{P}_{2}P$ through the intermediate state $a_0(980)$, where $P$ denotes a pseudoscalar meson. The quasi-two-body $D\to a_0(980{)}^{+}P$ decays are governed by the external $W$-emission diagram in which $a_0(980{)}^{+}$ is emitted. The predicted branching fractions in the $q\bar{q}$ model of $a_0(980)$ are too small by one to two orders of magnitude compared to experiment as the amplitude is suppressed by the smallness of the $a_0(980{)}^{+}$ decay constant, while those for $D^{+}\to a_0(980{)}^{0}P$ and $D^0\to a_0(980{)}^{-}P$ are usually too large. These discrepancies can be resolved provided that $a_0(980)$ is a tetraquark state. In this case, there exist two additional $T$-like topological amplitudes, denoted by $\overline{T}$ and $\tilde{T}$ which readily account for the discrepancies. An important implication of the tetraquark model is that the $D_s^{+}\to a_0(980{)}^{+}{\pi }^0+a_0(980{)}^0{\pi }^{+}$ decay is not a purely $W$-annihilation process as in the diquark model of $a_0(980)$; it receives dominant contributions from $\overline{T}$ newly noticed in this work. Therefore, measurements of $(D,D_s^{+})\to a_0(980)P$ decays lend strong support to the tetraquark picture of $a_0(980)$.

    hep-phhep-exPRD(2024)·14 citations
11. 11*

    Associated charged Higgs production within the 2HDM: $e^{-}{e}^{+}$ versus ${\mu }^{-}{\mu }^{+}$ colliders

    Brahim Ait Ouazghour🇲🇦 · Abdesslam Arhrib🇲🇦 · Kingman Cheung🇹🇼 · Es-said Ghourmin🇲🇦 · Larbi Rahili🇲🇦

    Our goal is to investigate the charged Higgs phenomenology in the framework of 2HDM at the upcoming $e^{+}{e}^{-}$ and muon colliders. We are primarily concerned with the associated production processes with a fermion pair: ${\ell }^{+}{\ell }^{-}\to {\tau }^{+}{\nu }_{\tau }{H}^{-}$ and ${\ell }^{+}{\ell }^{-}\to t\bar{b}{H}^{-}$, as well as with the W boson and a neutral Higgs boson: ${\ell }^{+}{\ell }^{-}\to W^{\pm }{H}^{\mp }S$ ($S=h,H,A$) and ${\ell }^{+}{\ell }^{-}\to W^{\pm }{H}^{\mp }Z$. We first update the results for $e^{+}{e}^{-}\to \{{\tau }^{+}{\nu }_{\tau }{H}^{-},t\bar{b}{H}^{-}\}$ and then discuss our findings for $e^{+}{e}^{-}\to \{W^{\pm }{H}^{\mp }S\}$ for various center of mass energies 500 GeV, 1 TeV, 1.5 TeV and 3 TeV. In the case of muon collider, we show that the new s-channel and t-channel diagrams can increase the cross sections by virtue of their Yukawa couplings. We systematically compare our results for the muon collider with those obtained at the International Linear (ILC) and Compact Linear (CLIC) colliders. We select benchmark points and conduct signal-background analyses, incorporating detector simulations. For a 3 TeV muon collider, our results show an exclusion region at the 2$\sigma$ level and a discovery region at the 5$\sigma$ level.

    hep-phPRD(2024)·13 citations
12. 12*

    Spontaneous CP violation, sterile neutrino dark matter, and leptogenesis

    Yanjin Jiang🇨🇳 · Norimi Yokozaki🇨🇳

    We constructed a model for spontaneous CP symmetry breaking in five-dimensional space-time that has a potential to solve the strong CP problem. To explain the nature of dark matter and the baryon asymmetry of the universe, three right-handed neutrinos and $U(1{)}_{B-L}$ gauge interaction are introduced in the bulk, in addition to the field contents of the Bento-Branco-Parada model. The wave-function profiles in the fifth dimension can suppress dangerous operators allowed by symmetries, and the scale of spontaneous CP symmetry breaking can be sufficiently large to be consistent with thermal leptogenesis. In this model, the lightest right-handed neutrino serves as dark matter with a mass of $\mathcal{O}(10)$ keV. This small mass and the necessarily small mixing are explained by the exponentially localized wave-function in the fifth dimension due to a bulk mass term. The correct relic abundance is achieved thanks to the $U(1{)}_{B-L}$ gauge interaction. The other heavy right-handed neutrinos explain the baryon asymmetry of the universe through leptogenesis, with the required CP violating phases generated by interactions involving heavy leptons.

    hep-phhep-exPLB(2025)·3 citations
13. 13*

    The effect of vorticity on the dynamical magnetic fields in heavy-ion collisions

    Anping Huang🇨🇳 · Xiang-Yu Wu🇨🇦 · Mei Huang🇨🇳

    Magnetic fields in heavy-ion collisions are pivotal and subject to diverse factors. In this study, we quantitatively investigate the impact of fluid vorticity on the evolution of magnetic fields in the 20-50\% centrality class in Au+Au collisions, with collision energies of $\sqrt{s_{NN}}=(7.7,14.5,19.6,27,39,62.4,200)$ GeV. Our results indicate that fluid vorticity leads to a delay in the evolution of the magnetic field, in which this effect becomes more pronounced as the collision energy decreases. Additionally, we have calculated the mean magnetic field values on the freeze-out hypersurface for various collision energies. Our simulation results align with the values inferred from experimental data of $\bar{\Lambda }-\Lambda$, within the error margins.

    hep-phhep-thnucl-thPRD(2024)·6 citations
14. 14*

    Predictions for $h_c$ and $h_b$ production at the LHC

    Sudhansu S. Biswal🇮🇳 · Sushree S. Mishra🇮🇳 · Monalisa Mohanty🇮🇳 · K. Sridhar🇮🇳

    The production cross sections of $h_c$ and $h_b$, the ${}^1{P}_1$ quarkonia can be predicted in Non-Relativistic Quantum Chromodynamics (NRQCD) using heavy quark symmetry. Our study includes predictions for both the integrated cross-section and the transverse momentum ($p_T$) distribution of $h_c$ ($h_b$) production at the Large Hadron Collider (LHC), using the decay process $h_c(h_b)\to {\eta }_c({\eta }_b)+\gamma$, ${\eta }_c({\eta }_b)\to p\overline{p}$. We demonstrate substaintial discrepancies in integrated cross-section and the $p_T$ distribution of ${}^1{P}_1$ quarkonia production at the LHC using Colour-Singlet Model (CSM), NRQCD and modified NRQCD. Measuring these resonances at the LHC could discriminate between these models, thereby offering further insights into the dynamics of quarkonium production. In addition, we compare the recent LHCb data for the integrated cross-section of $h_c$ production at $\sqrt{s}$ = 13 TeV in the kinematic range 5.0 $<$ $p_T$ $<$ 20.0 GeV and 2.0 $<$ $y$ $<$ 4.0 with the theoretical predictions using NRQCD and modified NRQCD. Modified NRQCD gives an agreement with the recent LHCb experimental data.

    hep-phhep-exPLB(2024)·4 citations
15. 15*

    Dirac Neutrinos and Dark Matter within a Minimal Discrete Symmetry Model

    Yakefu Reyimuaji🇨🇳 · Murat Abdughani🇨🇳

    We present a model that extends the standard model by incorporating the simplest discrete symmetry groups, $Z_2$ and $Z_3$. This model introduces vector-like leptons and a real scalar singlet. Based on this framework, we generate Dirac neutrino masses and explain the neutrino normal mass ordering. The model also aligns well with current oscillation data regarding theoretical values of the leptonic mixing angles and the Dirac CP-violating phase. Furthermore, it predicts that the atmospheric mixing angle falls in the higher octant and proposes a viable dark matter candidate. We also discuss other phenomenological aspects and future testability of the model.

    hep-phPLB(2025)·3 citations
16. 16*

    Composite heavy axion-like dark matter

    Pierluca Carenza🇸🇪 · Roman Pasechnik🇸🇪 · Zhi-Wei Wang🇨🇳

    We propose a novel class of Dark Matter (DM) candidates in the form of a heavy composite Axion-Like Particle (ALP) with highly suppressed electromagnetic interactions populating vast yet unexplored domains in the ALP parameter space. This is achieved for the first time in the simplest dark confining gauge theory yielding a new composite glueball ALP (GALP) DM coupling-mass relation found in terms of two distinct fundamental scales -- the large dark fermion mass scale and the dynamical scale of dark confinement. The presence of a heavy fermion portal between the visible (photons) and dark (GALPs) sectors ensures a strong radiative suppression of the GALP-photon coupling naturally without any fine-tuning. The observable features of heavy GALP DM in a minimal realization are controlled by only three physical parameters. Our work paves the road for a novel research field exploring the theory and phenomenology of composite ALPs in multi-messenger astrophysics and cosmology.

    hep-phastro-ph.COhep-thPRL(2025)·8 citations
17. 17*

    Kinetic Mixing, Proton Decay and Gravitational Waves in SO(10)

    Rinku Maji🇰🇷 · Qaisar Shafi🇺🇸

    We present an $SO(10)$ model in which a dimension five operator induces kinetic mixing at the GUT scale between the abelian subgroups $U(1{)}_{B-L}$ and $U(1{)}_R$. We discuss in this framework gauge coupling unification and proton decay, as well as the appearance of superheavy quasistable strings with $G\mu \sim 10^{-8}-10^{-5}$, where $\mu$ denotes the dimensionless string tension parameter. We use Bayesian analysis to show that for $G\mu$ values $\sim 4\times 10^{-7}-10^{-5}$, the gravitational wave spectrum emitted from the quasistable strings is in good agreement with the recent pulsar timing array data. Corresponding to $G\mu$ values $\sim 10^{-8}-2\times 10^{-7}$, proton decay is expected to occur at a rate accessible in the Hyper-Kamiokande experiment. Finally, we present the gravitational wave spectrum emitted by effectively stable strings with $G\mu \approx 10^{-8}$ that have experienced a certain amount of inflation. This can be tested with future detectors in the $\mu$Hz frequency range.

    hep-phastro-ph.COhep-thJHEP(2024)·10 citations
18. 18*

    Discovering an invisible Z' at the muon collider

    Anjan Kumar Barik🇮🇳 · Santosh Kumar Rai🇮🇳 · Aviral Srivastava🇮🇳

    We show in this letter how a heavy $(\mathcal{O}(TeV))$ invisible $Z^{\prime }$ gauge boson that will practically be out of reach of the Large Hadron Collider (LHC), can be discovered at the future muon collider. The new force carrier has a relatively stronger coupling with the beyond standard model (BSM) sector, while its interaction with the SM fields is much weaker. This weaker coupling is induced through mixing mechanisms, specifically via gauge kinetic mixing and the $Z-Z^{\prime }$ mixing. We consider a scenario where the new gauge boson decays mostly to charge-neutral long-lived particles and/or dark matter (DM). We show how producing and detecting this heavier invisible $Z^{\prime }$, that will be beyond the reach of even the very high luminosity LHC, becomes possible if it is produced in association with an energetic photon at the future muon collider. The on-shell production of the $Z^{\prime }$ will lead to a peak in the photon energy distribution, following the so-called radiative return phenomena and can lead to the accurate determination of the $Z^{\prime }$ mass and its interaction with SM particles.

    hep-phPLB(2025)·15 citations
19. 19*

    The Theoretical Study of ${\pi }^{+}p\to p{a}_0^{+}\varphi$ Reaction

    Aojia Xu🇨🇳 · Ruitian Li🇨🇳 · Xuan Luo🇨🇳 · Hao Sun🇨🇳

    We study the production of hyperon resonances in the ${\pi }^{+}p\to p{a}_0^{+}\varphi$ reaction within an effective Lagrangian approach. The model includes the production of $\Delta (1940)$ and $\Delta (1920)$ in the intermediate state excited by the $\rho$ and $p$ exchanges between the initial proton and $\pi$ meson. Due to the large contribution of $\rho$ exchange in $\Delta (1940)$ production, $\Delta (1940)$ is found a significant contribution near the threshold in this reaction. We provide total and differential cross section predictions for the reation and discuss the possible influence of model parameters, off-shell effects and branching ratios for $\Delta (1940)\to p{a}_0$ and $\Delta (1920)\to p{a}_0$ decays, which will be useful in future experimental studies. This reaction can provide a platform for studying the features of $\Delta (1940)$ resonance, especially the coupling to $p{a}_0$ channel.

    hep-phPRD(2024)·1 citation
20. 20*

    Relativistic spin hydrodynamics with momentum and spin-dependent relaxation time

    Samapan Bhadury🇵🇱

    Using the extended relaxation time approximation (ERTA) along with the theory of semi-classical spin, we develop a framework of relativistic dissipative spin hydrodynamics such that the relaxation time can depend on the momenta and spin of the constituent spin-1/2 particles. We also consider a general definition of the fluid four-velocity allowing the theory to be valid in a general frame and matching conditions. Consequently, we construct the frame-invariant bulk, shear, particle diffusion, and spin transport coefficients, showing that the evolution of fluid remains unaffected by spin in the limit of small polarization as was the case where the relaxation time was independent of spin or momentum.

    hep-phhep-thnucl-thPRC(2025)·18 citations
21. 21*

    The Sign of Gauge-Higgs Couplings at Future Lepton Colliders

    Carlos Henrique de Lima🇨🇦 · Douglas Tuckler🇨🇦

    This work investigates the capability of future lepton colliders to determine the sign of the gauge-Higgs coupling through the vector boson fusion (VBF) $Zh$ process. This channel offers a model-independent way to probe the sign of the gauge-Higgs coupling. Its sensitivity to interference effects and universal coupling with new physics makes it particularly effective. We show that a high-energy lepton collider such as CLIC can fully determine the sign of the gauge-Higgs coupling in a model-independent way and with high confidence.

    hep-phhep-exPRD(2025)·3 citations
22. 22*

    Collider and CMB complementarity of leptophilic dark matter with light Dirac neutrinos

    Debasish Borah🇮🇳 · Nayan Das🇮🇳 · Sahabub Jahedi🇮🇳 · Bhavya Thacker🇮🇳

    We study the discovery prospects of leptophilic dark matter (DM) in future lepton colliders by considering the light neutrinos to be of Dirac type. Adopting an effective field theory (EFT) approach, we write down dimension six operators connecting the standard model (SM) fields, light Dirac neutrinos and DM. Considering DM relic to be generated via the thermal freeze-out, we check the discovery prospects at future lepton colliders via mono-photon plus missing energy searches. The right chiral parts of light Dirac neutrinos get thermalised due to their interactions with the bath as well as leptophilic DM, leading to enhanced effective relativistic degrees of freedom $N_{\mathrm{eff}}$ within reach of future cosmic microwave background (CMB) experiments. The interplay of existing bounds from cosmological observations related to DM relic and $N_{\mathrm{eff}}$, direct and indirect detection of DM, astrophysics and collider observations leave promising discovery prospects at future electron and muon colliders along with complementary signatures at future CMB experiments.

    hep-phJHEP(2025)·18 citations
23. 23*

    Investigating the Timelike Compton scattering in photon-proton interactions at the EIC

    Ya-Ping Xie🇨🇳 · V. P. Gonçalves🇧🇷

    Information about the 3-dimensional description of the quark and gluon content of hadrons, described by the generalized parton distributions (GPDs), can be probed by exclusive processes in electron - proton ($ep$) collisions. In this letter, we investigate the timelike Compton scattering (TCS) in $ep$ collisions at the future electron - ion collider (EIC). Such process is characterized by the exclusive dilepton production through the subprocess $\gamma p\to {\gamma }^{\ast }p\to l^{+}{l}^{-}p$, with the real photon in the initial state being emitted by the incoming electron. Assuming a given model for the GPDs, the TCS differential cross-section is estimated, as well the contribution associated to the interference between the TCS and Bethe - Heitler (BH) amplitudes. Predictions for the TCS, BH and interference contributions are presented considering the kinematical range expected to be covered by the EIC detectors. Moreover, the polarized photon asymmetry is also studied. Our results indicated that a future experimental analysis, considering photon circular polarizations, can be useful to probe the interference contribution and constrain the description of the GPDs for the proton.

    hep-phEPJC(2024)·3 citations
24. 24*

    Neutral pion polarizabilities from four-point functions in lattice QCD

    Frank X. Lee🇺🇸 · Walter Wilcox🇺🇸 · Andrei Alexandru🇺🇸 · Chris Culver🇬🇧 · Shayan Nadeem🇺🇸

    We report a proof-of-principle lattice QCD simulation of the electric and magnetic polarizabilities for a neutral pion in the four-point function method. The results are based on the same quenched Wilson ensembles on a $24^3\times 48$ lattice at $\beta =6.0$ with pion mass from 1100 to 370 MeV previously used for a charged pion. For electric polarizability, the results are largely consistent with those from the background field method and ChPT. In contrast, there are significant differences for magnetic polarizability among the four-point function method, the background field method, and ChPT. The situation points to the potentially important role of disconnected diagrams for a neutral pion. We elucidate a transparent quark decomposition in the four-point function method that can be used to shed light on the issue.

    ↳ hep-lathep-phnucl-thNPB(2024)·5 citations
25. 25*

    Gravitational Waves from High Temperature Strings

    Andrew R. Frey🇨🇦 · Ratul Mahanta🇨🇦 · Anshuman Maharana🇮🇳 · Fernando Quevedo🇬🇧 · Gonzalo Villa🇬🇧

    We study finite temperature effects in string cosmology and their potential gravitational wave signature. Expanding on our recent work arXiv:2310.11494 , we consider a general configuration of highly excited open and closed strings at high enough temperature to be in the Hagedorn phase in 3+1 dimensions, in order to explore its cosmological implications. We find conditions, which can be satisfied in compactifications with moduli stabilization, that allow the long strings to remain in equilibrium in a controlled effective field theory, with equilibration driven by the joining and splitting of the dominant open string population. We calculate the emission rate of gravitons by long open strings, which we show is determined by ten dimensional flat space transition amplitudes available in the literature, and then find the total gravitational wave spectrum generated by the gas of long strings. The gravitational wave spectrum has robust characteristics. It peaks at frequencies of order 50-100 GHz, the same as for gravitational waves from the reheating epoch of the Standard Model. But the amplitude of the string signal is significantly larger than predicted by the Standard Model and its field theoretic extensions. The amplitude and other physical observables (such as the contribution to $\Delta N_{\text{e}ff}$) are directly proportional to the string scale $M_s$; indicating that a potential signal may also determine the string scale. Our calculations provide one of the few examples of a signal of stringy origin that dominates over the field theory predictions. We give a physical explanation of our results and discuss further implications.

    ↳ hep-thastro-ph.COhep-phJHEP(2024)·20 citations
26. 26*

    On the conformal limit of a QED-inspired model

    O Oliveira🇵🇹 · T Frederico🇧🇷 · W de Paula🇧🇷

    A conformal invariant QED-inspired model is solved for a general covariant linear gauge using the Dyson-Schwinger equations for the propagators assuming a pure vector like interaction. The leading corrections to the asymptotic solutions and the exponents, that characterize the corrections to each of the two fermion propagator functions, are computed as a function of the coupling and gauge fixing parameter $\xi$. For the scalar component of the fermion propagator our findings generalizes for linear covariant gauges previous results found in the literature and reproduce the outcome of the perturbative analysis of quenched QED in the Landau gauge. Our solution for the exponent associated with vector component of the fermion propagator is new and, in the weak coupling regime, agrees with the estimation based on the perturbative analysis of quenched QED. Of the two critical exponents describing the conformal limit of the vector interaction, one of them is, in QED, associated with the regime where chiral symmetry is broken dynamically, which demands one mass scale, namely the Miransky scaling. A second mass scale has to be introduced at larger coupling constants and is associated with a change on the nature of the fermion wave function. This provides one example, that it is possible to find two interwoven cycles in Quantum Field Theory, albeit in a truncated framework, as it is known in the quantum few-body problem in the limit of a zero-range interaction.

    ↳ hep-thhep-phEPJC(2024)·3 citations
27. 27*

    Non-invertible flavor symmetries in magnetized extra dimensions

    Tatsuo Kobayashi🇯🇵 · Hajime Otsuka🇯🇵

    We discuss non-invertible symmetries in toroidal compactifications of higher dimensional Yang-Mills theory with magnetic fluxes, which can be regarded as an effective action of type IIB string theory with magnetized D-branes. Specifically, we derive fusion rules of discrete isometry operators, which are invariant under the ${\mathbb{Z}}_N$ orbifold twist. It turns out that degenerate chiral zero-modes non-trivially transform under the non-invertible symmetries in the context of quantum mechanics. Hence, non-invertible symmetries correspond to flavor symmetries of chiral zero modes and determine their flavor structure. We explicitly show the representations and selection rules of chiral zero modes on their wave functions. These zero modes may correspond to generations of quarks and leptons in four-dimensional low-energy effective field theory.

    ↳ hep-thhep-phJHEP(2024)·45 citations
28. 28*

    Flea on the elephant: Tidal Love numbers in subsolar primordial black hole searches

    Valerio De Luca🇺🇸 · Gabriele Franciolini🇨🇭 · Antonio Riotto🇨🇭

    Detecting subsolar objects in black hole binary mergers is considered a smoking gun signature of primordial black holes. Their supposedly vanishing tidal Love number is generically thought to help distinguish them from other subsolar and more deformable compact objects, such as neutron stars. We show that a large and detectable Love number of primordial black holes can be generated in the presence of even small disturbances of the system, thus potentially jeopardizing their discovery. However, such small perturbations are not tightly bound and are therefore disrupted before the mergers. We show that they leave a characteristic signature in the gravitational waveform that could be observed with current and future gravitational wave detectors. Thus, they may still hint towards the primordial nature of the black holes in the merger. Finally, we demonstrate that disregarding possible environmental effects in the matched-filter search for subsolar gravitational wave events can lead to a decreased sensitivity in the detectors.

    ↳ gr-qcastro-ph.COhep-phhep-thPRD(2024)·27 citations
29. 29*

    Tidal deformability of black holes surrounded by thin accretion disks

    Enrico Cannizzaro🇵🇹 · Valerio De Luca🇺🇸 · Paolo Pani🇮🇹

    The tidal Love numbers of self-gravitating compact objects describe their response to external tidal perturbations, such as those from a companion in a binary system, offering valuable insights into their internal structure. For static tidal fields, asymptotically flat black holes in vacuum exhibit vanishing Love numbers in general relativity, even though this property is sensitive to the presence of an external environment. In this work we study the tidal deformability of black holes surrounded by thin accretion disks, showing that the Love numbers could be large enough to mask any effect of modified gravity and to intrinsically limit tidal tests of black-hole mimickers. Furthermore, we investigate the measurability of the tidal parameters with next-generation gravitational wave experiments, like LISA and Einstein Telescope. Our findings suggest that these parameters could be measured with high precision, providing a powerful tool to probe the environment around coalescing binary systems.

    ↳ astro-ph.HEastro-ph.COgr-qchep-ph+1PRD(2024)·33 citations
30. 30*

    Cosmology and nuclear-physics implications of a subsolar gravitational-wave event

    Francesco Crescimbeni🇮🇹 · Gabriele Franciolini🇨🇭 · Paolo Pani🇮🇹 · Massimo Vaglio🇮🇹

    Detecting a compact subsolar object would have profound implications in physics, the reach of which depends on the nature of the object. Here we explore such consequences for a putative subsolar-mass gravitational wave event detected by the LIGO-Virgo-KAGRA Collaboration. We forecast that the nature of a subsolar binary (made of light neutron stars, primordial black holes, or more exotic compact objects) can be inferred with a great statistical confidence level already during the ongoing fourth observing run, based on the large tidal deformability effects on the signal. The detection of a primordial black hole would have implications for cosmology and dark matter scenarios, while the measurement of the tidal deformability of a subsolar neutron star could rule out or confirm the existence of strange stars made of quarks.

    ↳ astro-ph.HEgr-qchep-phnucl-thPRD(2025)·19 citations
31. 31*

    The asymptotic Hopf Algebra of Feynman Integrals

    Mrigankamauli Chakraborty🇩🇪 · Franz Herzog🇬🇧

    The method of regions is an approach for developing asymptotic expansions of Feynman Integrals. We focus on expansions in Euclidean signature, where the method of regions can also be formulated as an expansion by subgraph. We show that for such expansions valid around small/large masses and momenta the graph combinatorial operations can be formulated in terms of what we call the asymptotic Hopf algebra. This Hopf algebra is closely related to the motic Hopf algebra underlying the $R^{\ast }$ operation, an extension of Bogoliubov's $R$ operation, to subtract both IR and UV divergences of Feynman integrals in the Euclidean. We focus mostly on the leading power, for which the Hopf algebra formulation is simpler. We uncover a close connection between Bogoliubov's $R$ operation in the Connes-Kreimer formulation and the remainder $\mathcal{R}$ of the series expansion, whose Hopf algebraic structure is identically formalised in the corresponding group of characters. While in the Connes-Kreimer formulation the UV counterterm is formalised in terms of a twisted antipode, we show that in the expansion by subgraph a similar role is played by the integrand Taylor operator. To discuss the structure of higher power expansions we introduce a novel Hopf monoid formulation.

    ↳ hep-thhep-phmath-phmath.MPJHEP(2025)·5 citations
32. 32*

    Nucleon Transversity from lattice QCD

    Constantia Alexandrou (Univ. of Cyprus)🇨🇾

    We give a brief overview of recent progress in lattice QCD simulations that is enabling precision studies of the three-dimensional structure of the nucleon. We present results on nucleon charges and second Mellin moments of parton distribution functions and generalized parton distributions, highlighting results obtained at the continuum limit using only gauge ensembles simulated with physical quark masses. The tensor charge and transversity moments are determined with controlled systematics and used to extract nucleon transverse density distributions. We also discuss progress towards the direct evaluation of generalized parton distributions in lattice QCD and the impact they are having on phenomenology.

    ↳ hep-lathep-exhep-phPoS(2024)·3 citations
33. 33*

    Collisional and radiative energy loss in small systems

    Coleridge Faraday🇿🇦 · W. A. Horowitz🇿🇦

    We present an energy loss model which includes small system size corrections to both the radiative and elastic energy loss. Our model is used to compute the nuclear modification factor $R_{AB}$ of light and heavy flavor hadrons, averaged over realistic collision geometries for central and peripheral $A+A$ and central $p/d/{}^3\text{He}+A$ collisions at LHC and RHIC. We find that the predicted suppression in small systems is almost entirely due to elastic energy loss. Our results are keenly sensitive to the crossover between elastic energy loss calculated with hard thermal loop propagators and vacuum propagators, respectively, which leads to a large theoretical uncertainty. We find that the $R_{AB}$ is largely insensitive to the form of the elastic energy loss distribution - Gaussian or Poisson - surprisingly so in small systems where the central limit theorem is inapplicable. We present an expansion of the $R_{AB}$ in terms of the moments of the energy loss probability distribution, which allows for a rigorous understanding of the dependence of the $R_{AB}$ on the underlying energy loss distribution.

    ↳ nucl-thhep-phPRC(2025)·11 citations
34. 34*

    Evidence of Coulomb liquid phase in few-electron droplets

    Jashwanth Shaju🇫🇷 · Elina Pavlovska🇱🇻 · Ralfs Suba🇱🇻 · Junliang Wang🇨🇳 · Seddik Ouacel🇫🇷 · Thomas Vasselon🇫🇷 · Matteo Aluffi🇫🇷 · Lucas Mazzella🇫🇷 · Clément Geffroy🇫🇷 · Arne Ludwig🇩🇪 · Andreas D. Wieck🇩🇪 · Matias Urdampilleta🇫🇷 and 3 other authors

    Emergence of universal collective behaviour from interactions within a sufficiently large group of elementary constituents is a fundamental scientific paradigm. In physics, correlations in fluctuating microscopic observables can provide key information about collective states of matter such as deconfined quark-gluon plasma in heavy-ion collisions or expanding quantum degenerate gases. Mesoscopic colliders, through shot-noise measurements, have provided smoking-gun evidence on the nature of exotic electronic excitations such as fractional charges, levitons and anyon statistics. Yet, bridging the gap between two-particle collisions and the emergence of collectivity as the number of interacting particles increases remains a challenging task at the microscopic level. Here we demonstrate all-body correlations in the partitioning of electron droplets containing up to N = 5 electrons, driven by a moving potential well through a Y-junction in a semiconductor device. Analyzing the partitioning data using high-order multivariate cumulants and finite-size scaling towards the thermodynamic limit reveals distinctive fingerprints of a strongly-correlated Coulomb liquid. These fingerprints agree well with a universal limit where the partitioning of a droplet is predicted by a single collective variable. Our electron-droplet collider provides critical insight into the interplay of confinement and interaction effects in small electron systems and highlights a new way to study engineered states of matter.

    ↳ cond-mat.mes-hallcond-mat.str-elhep-exhep-phNature(2025)·3 citations
35. 35*

    Quasitopological Lifshitz dilaton black brane

    A. Bazrafshan🇮🇷 · M. Ghanaatian🇮🇷 · S. Rezaei🇮🇷 · Gh. Forozani🇮🇷

    We construct a new class of $(n+1)$-dimensional Lifshitz dilaton black brane solutions in the presence of the cubic quasitopological gravity for a flat boundary. The related action supports asymptotically Lifshitz solutions by applying some conditions which are used throughout the paper. We have to add a new boundary term and some new counterterms to the bulk action to have finite solutions. Then we define a finite stress tensor complex by which we can calculate the energy density of the quasitopological Lifshitz dilaton black brane. It is not possible to obtain analytical solutions, and so we use some expantions to probe the functions behaviors near the horizon and at the infinity. Combining the equations, we can attain a total constant along the coordinate $r$. At the horizon, this constant is proportional to the product of the temperature and the entropy and at the infinity, the total constant shows the energ density of the quasitopological Lifshitz dilaton black brane. Therefore, we can reach to a relation between the conserved quantities temperature, entropy and the energy density and get a smarr-type formula. Using the first law of thermodynamics, we can find a relation between the entropy and the temperature and then ontain the heat capacity. Our results show that the quasitopological Lifshitz dilaton black brane solutions are thermally stable for each positive values of the dynamical critiacl exponent, $z$.

    ↳ hep-thgr-qchep-ph0 citations
36. 36*

    Cosmological Parameter Estimation with a Joint-Likelihood Analysis of the Cosmic Microwave Background and Big Bang Nucleosynthesis

    Cara Giovanetti🇺🇸 · Mariangela Lisanti🇺🇸 · Hongwan Liu🇺🇸 · Siddharth Mishra-Sharma🇺🇸 · Joshua T. Ruderman🇺🇸

    We present the first joint-likelihood analysis of Big Bang Nucleosynthesis (BBN) and Cosmic Microwave Background (CMB) data. Bayesian inference is performed on the baryon abundance and the effective number of neutrino species, $N_{\mathrm{eff}}$, using a CMB Boltzmann solver in combination with LINX, a new flexible and efficient BBN code. We marginalize over Planck nuisance parameters and nuclear rates to find $N_{\mathrm{eff}}=3.08_{-0.13}^{+0.13},2.94_{-0.16}^{+0.16},$ or $2.98_{-0.13}^{+0.14}$, for three separate reaction networks. This framework enables robust testing of the Lambda Cold Dark Matter paradigm and its variants with CMB and BBN data.

    ↳ astro-ph.COhep-phPRD(2025)·13 citations
37. 37*

    Confronting Cold New Early Dark Energy and its Equation of State with Updated CMB, Supernovae, and BAO Data

    Aleksandr Chatrchyan🇸🇪 · Florian Niedermann🇸🇪 · Vivian Poulin🇫🇷 · Martin S. Sloth🇩🇰

    Cold New Early Dark Energy (Cold NEDE) addresses the Hubble tension through a triggered vacuum phase transition in the dark sector. In this paper, we constrain a phenomenological fluid model using recent cosmic microwave background likelihoods based on Planck NPIPE data alongside baryonic acoustic oscillations (BAO) and supernovae data from Pantheon+. Exploiting the enhanced constraining power of the datasets, we introduce and study an extended version of the NEDE fluid model in which the equation of state parameter $w_{\mathrm{NEDE}}$, characterizing the post-phase transition fluid, is allowed to evolve with non-vanishing derivatives $d{w}_{\mathrm{NEDE}}/d\ln a$ and $d^2{w}_{\mathrm{NEDE}}/d(\ln a{)}^2$. Our results indicate that data is compatible with a rather simple time dependence that could arise from a mixture of radiation and a stiff fluid. With the updated datasets, the base and extended models still show a significant reduction of the DMAP tension from $6.3\sigma$ in $\Lambda$CDM down to $3.5\sigma$ with a small simultaneous reduction of the $S_8$ tension, slightly improving over recent findings for the axion-like early dark energy model. Finally, we also provide a first test of the model against new BAO data from the Dark Energy Spectroscopic Instrument (DESI) survey. Replacing the previous BAO constraints in our analysis with the new ones, the tension is further reduced to $2.6\sigma$, reaffirming the Cold NEDE model as a promising solution to the Hubble tension.

    ↳ astro-ph.COhep-phPRD(2025)·34 citations
38. 38*

    LINX: A Fast, Differentiable, and Extensible Big Bang Nucleosynthesis Package

    Cara Giovanetti🇺🇸 · Mariangela Lisanti🇺🇸 · Hongwan Liu🇺🇸 · Siddharth Mishra-Sharma🇺🇸 · Joshua T. Ruderman🇺🇸

    We introduce LINX (Light Isotope Nucleosynthesis with JAX), a new differentiable public Big Bang Nucleosynthesis (BBN) code designed for fast parameter estimation. By leveraging JAX, LINX achieves both speed and differentiability, enabling the use of Bayesian inference, including gradient-based methods. We discuss the formalism used in LINX for rapid primordial elemental abundance predictions and give examples of how LINX can be used. When combined with differentiable Cosmic Microwave Background (CMB) power spectrum emulators, LINX can be used for joint CMB and BBN analyses without requiring extensive computational resources, including on personal hardware.

    ↳ astro-ph.COhep-phPRD(2025)·26 citations
39. 39*

    Cosmic Rays: High Energy Particle Interactions in the Atmosphere -- Memorial Issue for Prof. Dr. Thomas K. Gaisser (Editorial)

    Frank G. Schröder🇺🇸 · Serap Tilav🇺🇸

    This special issue of the Astroparticle Physics journal is dedicated to the memory of Thomas Korff Gaisser, the Martin A. Pomerantz Professor Emeritus of Physics at the University of Delaware. Tom was one of the most prominent scientists in cosmic-ray and astroparticle physics, and also one of the founding editors of this very journal. A theoretical particle physicist by training, he dedicated his career to cosmic-ray physics. He worked on the phenomenology of high-energy particle interactions in the atmosphere, modeling extensive air showers, including the famous 'Gaisser-Hillas' function describing their longitudinal profile. A focus of his work were muon and neutrino fluxes resulting from cosmic-ray showers in the atmosphere, and their measurement with specialized experiments at the South Pole.

    ↳ astro-ph.HEhep-phAstropart.Phys.(2024)·0 citations
40. 40*

    Prospects for searching for sterile neutrinos with gravitational wave and $\gamma$-ray burst joint observations

    Lu Feng🇨🇳 · Tao Han🇺🇸 · Jing-Fei Zhang🇺🇸 · Xin Zhang🇺🇸

    Sterile neutrinos can influence the evolution of the universe, and thus cosmological observations can be used to detect them. Future gravitational wave (GW) observations can precisely measure absolute cosmological distances, helping to break parameter degeneracies generated by traditional cosmological observations. This advancement can lead to much tighter constraints on sterile neutrino parameters. This work provides a preliminary forecast for detecting sterile neutrinos using third-generation GW detectors in combination with future short $\gamma$-ray burst observations from a THESEUS-like telescope, an approach not previously explored in the literature. Both massless and massive sterile neutrinos are considered within the $\Lambda$CDM cosmology. We find that using GW data can greatly enhance the detection capability for massless sterile neutrinos, reaching 3$\sigma$ level. For massive sterile neutrinos, GW data can also greatly assist in improving the parameter constraints, but it seems that effective detection is still not feasible.

    ↳ astro-ph.HEastro-ph.COgr-qchep-phCommun.Theor.Phys.(2025)·14 citations
41. 41*

    Study of the relativistic charged particle beam propagation in Earth's magnetic field

    Meihua Fang🇺🇸 · Zheng liang · Yingkui Gong🇨🇳 · Jianfei Chen🇨🇳 · Guiping Zhu🇺🇸 · Ting Liu🇨🇳 · Yu Tian🇺🇸 · Yu Zhou🇯🇵

    Relativistic charged particle beam can be used as destructive beam weapons in space for debris removal tasks. The trajectories of charged particles are affected by both electric and magnetic forces in the Earth's magnetic field. In this paper, we firstly analyzed the correlation parameters of the charged particle beam as a weapon when it propagated in the geomagnetic field. Then the models were constructed based on COMSOL Multiphysics and the IGRF model was adopted in the simulation. The gyro-radius and the related uncertainty were analyzed by simulation of the charged particle transport in the geomagnetic field at different altitudes. The charged beam spot radius divergency was also simulated. The magnetic field pinch effect can be found and can limit the beam spreading.

    ↳ physics.space-phastro-ph.IMhep-phAdv.High Energy Phys.(2024)·0 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.