Fri·Jun 21, 2024Friday·June 21, 2024

1. 01*

   Non-global logarithms up to four loops at finite-N${}_c$ for V/H+jet processes at hadron colliders

   K. Khelifa-Kerfa🇩🇿

   We extend our previous work [1] on calculating non-global logarithms in $e^{+}{e}^{-}$ annihilation to Higgs/vector boson production in association with a single hard jet at hadron colliders. We analytically compute non-global coefficients in the jet mass distribution up to four loops using the anti-k${}_t$ jet algorithm. Our calculations are performed in the eikonal approximation, assuming strong energy ordering for the emitted gluons, thus capturing only the leading logarithms of the distribution. We compare our analytical results with the all-orders large-N${}_c$ numerical solution. In general, the gross features of the non-global logarithm distribution observed in the $e^{+}{e}^{-}$ case remain valid for the V/H+jet processes.

   hep-phhep-thJHEP(2024)·6 citations
2. 02*

   Multi-messenger Astronomy with Quenched Superradiance

   Indra Kumar Banerjee🇮🇳 · Soumya Bonthu🇮🇳 · Ujjal Kumar Dey🇮🇳

   We propose a novel method to study the ultra-light bosons, where compact rotating objects undergo the phenomenon of quenched superradiance to create gravitational waves and neutrino flux signals. The neutrino flux results from appropriate coupling between the ultra-light bosons and the neutrinos. We consider a heavy sterile neutrino generation from ultralight scalar, which later results in active neutrino flux through neutrino oscillations, whereas we consider active neutrino generation directly from the vector bosons. We study the intertwining of gravitational waves and neutrino flux signals produced from a single source and elaborate if and when the signals can be detected in existing and upcoming experiments in a direct manner.

   hep-phastro-ph.HEgr-qcPRD(2025)·6 citations
3. 03*

   Effective theory tower for $\mu \to e$ conversion

   Wick Haxton🇺🇸 · Kenneth McElvain🇺🇸 · Tony Menzo🇺🇸 · Evan Rule🇺🇸 · Jure Zupan🇺🇸

   We present theoretical predictions for $\mu \to e$ conversion rates using a tower of effective field theories connecting the UV to nuclear physics scales. The interactions in nuclei are described using a recently developed nonrelativistic effective theory (NRET) that organizes contributions according to bound nucleon and muon velocities, ${\vec{v}}_N$ and ${\vec{v}}_{\mu }$, with $|{\vec{v}}_N|>|{\vec{v}}_{\mu }|$. To facilitate the top-down matching, we enlarge the set of Lorentz covariant nucleon-level interactions mapped onto the NRET operators to include those mediated by tensor interactions, in addition to the scalar and vector interactions already considered previously, and then match NRET nonperturbatively onto the Weak Effective Theory (WET). At the scale $\mu \approx 2$ GeV WET is formulated in terms of $u$, $d$, $s$ quarks, gluons and photons as the light degrees of freedom, along with the flavor-violating leptonic current. We retain contributions from WET operators up to dimension 7, which requires the full set of 26 NRET operators. The results are encoded in the open-source Python- and Mathematica-based software suite MuonBridge, which we make available to the theoretical and experimental communities interested in $\mu \to e$ conversion.

   hep-phhep-exnucl-thJHEP(2024)·35 citations
4. 04*

   Quasi-Dirac Heavy Neutral Leptons in the Left-Right Symmetric Model

   Oleksii Mikulenko🇳🇱

   We discuss the phenomenology of a pair of degenerate GeV-scale Heavy Neutral Leptons within the Left-Right Symmetric Model (LRSM) framework, with the third fermion serving as a dark matter candidate. We highlight the potential of the recently approved SHiP experiment to test the existence of the light DM species, and the signatures of lepton number violation as a possible experimental probe of the model in various experiments. Our findings include concrete predictions, in some part of the model's parameter space, for the effective right-handed couplings $(V_e^R{)}^2:(V_{\mu }^R{)}^2:(V_{\tau }^R{)}^2=0.16:0.47:0.38$ (normal neutrino hierarchy), $0.489:0.22:0.30$ (inverted hierarchy) of the degenerate pair.

   hep-phJHEP(2025)·4 citations
5. 05*

   Topological amplitudes of charmed baryon decays in the $SU(3{)}_F$ limit

   Di Wang🇨🇳 · Jin-Feng Luo🇨🇳

   Charmed baryon decay plays an important role in studying the weak and strong interactions. Topological diagram is an intuitive tool for analyzing the dynamics of heavy hadron decays. In this work, we investigate the topological diagrams of charmed baryon antitriplet (${\mathcal{B}}_{c\overline{3}}$) decays into a light baryon octet (${\mathcal{B}}_8$) and a light meson ($M$). The topological diagrams of the ${\mathcal{B}}_{c\overline{3}}\to {\mathcal{B}}_8^{S}M$ modes (where ${\mathcal{B}}_8^S$ and ${\mathcal{B}}_8^A$ are the $q_1\leftrightarrow q_2$ symmetric and antisymmetric octets) and the diagrams with a quark loop are presented for the first time. The completeness of topologies is confirmed by permutation. The linear relations of topologies are obtained by deriving the relation between the topological amplitudes constructed by the third- and second-rank octet tensors. The equations of $SU(3)$ irreducible amplitudes decomposed by topologies are derived through two different intermediate amplitudes. However, the inverse solution does not exist since the number of topologies exceeds number of $SU(3)$ irreducible amplitudes. Applying this framework to the Standard Model, it is found there are thirteen independent $SU(3)$ irreducible amplitudes contributing to the ${\mathcal{B}}_{c\overline{3}}\to {\mathcal{B}}_{8}M$ decays. Among these, four amplitudes associated with three-dimensional operators are significant for $CP$ asymmetries. Considering the suppressions due to small Cabibbo-Kobayashi-Maskawa matrix elements $V_{cb}^{\ast }{V}_{ub}$ and the Körner-Pati-Woo theorem, the branching fractions of charmed baryon decays are dominated by five $SU(3)$ irreducible amplitudes in the $SU(3{)}_F$ limit.

   hep-phPRD(2024)·18 citations
6. 06*

   Dynamics of Phase Transition in Quark-Gluon Plasma Droplet Formation under Magnetic Field

   Agam K. Jha🇮🇳 · Aviral Srivastava🇮🇳

   Pre-existing density of states for a Quark-Gluon Phase, based on Thomas-Fermi and Bethe mode, is expanded by incorporation of new variables. Results from recent study indicate that perturbations in the form of a finite non-zero chemical potential T, B, dynamic thermal masses M and of course Temperature T are indeed vital to fully comprehend the formation and dynamics of QGP. Simulations depict an overall increase in the stability of QGP in the paradigm of the statistical model. On the top of Free Energy, Entropy and heat capacity are calculated for the phase transition. The overall qualitative behavior, of entropy or Heat Capacity determines the order of phase transition of the QGP. Investigation of order of phase transition is carried out in this study through Monte-Carlo based differential element, which ensures the inclusion of the randomness of the collisions at the particle colliders.

   hep-phnucl-thInt.J.Mod.Phys.A(2025)·1 citation
7. 07*

   {\pi} Meson-Octet Baryon Coupling Constant Obtained by Hard-Wall AdS/QCD Model

   Mamedov Shahin🇦🇿 · Taghiyeva Shahnaz🇦🇿

   The paper studies a strong coupling constant between {\pi} meson and octet baryon using the hard-wall AdS/QCD model, which considers SU(3)f symmetry-breaking effects. Briefly mentioned are profile functions for pseudoscalar meson and baryon fields. The obtained baryon coupling constants are in agreement with those obtained in theoretical calculations.

   hep-phRuss.Phys.J.(2024)·0 citations
8. 08*

   Exploring new physics via effective interactions

   Ekata Singh🇮🇳 · Hrishabh Bharadwaj🇮🇳 · Devisharan🇮🇳

   We investigate self-conjugate Dark Matter (DM) particles that primarily interact with standard model electroweak gauge bosons within an effective field theoretical framework. Our analysis focuses on effective contact interactions, invariant under the standard model gauge group, between Majorana fermions, and real scalar DM, with SM neutral electroweak gauge bosons. We calculate the Wilson coefficients for interaction terms up to dimension-8 and establish constraints on the theory's parameters. These constraints are derived from the observed relic density, and indirect detection observations. We discuss the potential for dark matter-nucleon scattering in direct detection experiments. Additionally, we utilize low-energy LEP data to assess sensitivity to the pair production of low-mass ($\le$ 80 GeV) DM particles. Furthermore, we highlight the potential of the proposed International Linear Collider (ILC) in probing effective operators through the pair production of DM particles with masses $\ge$ 50 GeV in association with mono-photons.

   hep-phInt.J.Mod.Phys.A(2024)·5 citations
9. 09*

   Complex Dark Photon Dark Matter EFT

   Enrico Bertuzzo🇮🇹 · Tommaso Sassi🇮🇹 · Andrea Tesi🇮🇹

   We construct an effective field theory for complex Stueckelberg dark photon dark matter. Such an effective construction can be realized by writing down a complete set of operators up to dimension six built with the complex dark photon and Standard Model fields. Classifying the effective operators, we find that in order to properly take into account the non-renormalizable nature of an interacting massive vector, the size of the Wilson coefficients should be naturally smaller than naively expected. This can be consistently taken into account by a proper power counting, that we suggest. First we apply this to collider bounds on light dark matter, then to direct detection searches by extending the list of non-relativistic operators to include the case of complex vectors. In the former we correctly find scaling limits for small masses, while in the latter we mostly focus on electric dipole interactions, that are the smoking gun of this type of dark matter. Simple UV completions that effectively realize the above scenarios are also outlined.

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

    Collective description of low energy mesonic states

    Tochtli Yepez-Martinez🇲🇽 · Octavio Rico Trejo🇲🇽 · Peter Otto Hess🇲🇽 · Osvaldo Civitarese🇦🇷

    The phenomenology of hadronic states at high energy is well described in the framework of Quantum Chromodynamics. The theory, well established by now, cannot be applied to the description of quark-antiquark states at low energy unless their degrees of freedom are treated as effective ones, a condition resulting from confinement. Own to the similarities with other quantum many-body systems we have adopted a non-perturbative scheme where quarks are treated as quasiparticles, which further interact between them, allowing meson-like states to be described as collective superposition of quasiparticle-pairs. The results of the calculations, performed in the context of the random phase approximation method, show that this scheme is a suitable one to describe meson states up to energies of the order of couple of GeV.

    hep-phPRD(2024)·1 citation
11. 11*

    Parity and lepton masses in the left-right symmetric model

    Ravi Kuchimanchi🇺🇸

    Curiously in the minimal left right symmetric model, chiral symmetry that protects the electron's mass ($m_e$), due to parity (P), implies in the symmetry limit the vanishing of its neutrino mixing angles. We break the chiral symmetry softly (or spontaneously if it is gauged) to generate the observed large neutrino mixing angles at the tree-level. The electron then acquires its mass on renormalization group equation (RGE) running due to its neutrino's mixing, and in turn determines the $B-L$ gauge symmetry breaking scale ($v_R$) to be $10^{10}GeV\lesssim v_R\le 10^{15}GeV.$ If the muon's mass is also generated radiatively, the $B-L$ breaking scale is $\sim 10^{14-15}$ GeV. Regardless of the high scale of $v_R$, this is a testable model since on RGE running and P breaking, a large strong CP phase ($\bar{\theta }>>10^{-10}$) which depends logarithmically on $v_R$ is generated if there is $\mathcal{O}(1)$ CP violation in leptonic Yukawa couplings. Hence we expect that leptonic CP phases including the Dirac CP phase ${\delta }_{CP}$ of the PMNS matrix must be consistent with $0$ or $180^o$ to within a degree, which can be verified or excluded by neutrino experiments such as DUNE and Hyper-Kamiokande. In lieu of P, if charge conjugation C is used, the same results follow. However with C and no P, axions would likely need to be added anyway, in which case there is no constraint on ${\delta }_{CP}$.

    hep-phhep-exPRD(2024)·5 citations
12. 12*

    Constraints on Heavy Asymmetric and Symmetric Dark Matter from the Glashow Resonance

    Qinrui Liu🇨🇦 · Ningqiang Song🇨🇳 · Aaron C. Vincent🇨🇦

    The decay of asymmetric dark matter (ADM) can lead to distinct neutrino signatures characterized by an asymmetry between neutrinos and antineutrinos. In the high-energy regime, the Glashow resonant interaction ${\bar{\nu }}_e+e^{-}\to W^{-}$ yields an increase in sensitivity to the neutrino flux, and stands out as the only way of discerning the antineutrino component in the diffuse high-energy astrophysical neutrino flux. This offers a unique opportunity in the search for dark matter with masses above the PeV scale. We examine the neutrino signal stemming from ADM decay and set the first stringent constraints on ADM lifetime ${\tau }_X$. For ADM with mass $m_X\gtrsim 10$~PeV, we {exclude} ${\tau }_X\lesssim 10^{29}$s using the data from the recent IceCube search for Glashow resonance events. Our projections further show that sensitivities at the forthcoming IceCube-Gen2 could approach $10^{30}$s, depending on the decay channel. The current constraints on symmetric dark matter decay to neutrinos are also improved by up to a factor of 3 thanks to the Glashow resonance.

    hep-phastro-ph.HEPRD(2025)·9 citations
13. 13*

    Anomalous thresholds in $B\to (P,V){\gamma }^{\ast }$ form factors

    Simon Mutke🇩🇪 · Martin Hoferichter🇨🇭 · Bastian Kubis🇩🇪

    We study the effects of anomalous thresholds on the non-local form factors describing the hadronization of the light-quark contribution to $B\to (P,V){\gamma }^{\ast }$ transitions. Starting from a comprehensive discussion of anomalous thresholds in the triangle loop function for different mass configurations, we detail how the dispersion relation for $\pi \pi$ intermediate states is affected by contour deformations mandated by the anomalous branch points. Phenomenological estimates of the size of the anomalous contributions to the form factors are provided with couplings determined from measured branching fractions and Dalitz plot distributions. Our key finding is that anomalous effects are suppressed on the $\rho (770)$ resonance, while off-peak the effects can become as large as $\mathcal{O}(10\%)$ of the full (light-quark-loop induced) non-local form factors. We comment on future generalizations towards higher intermediate states and the charm loop, outlining how the dispersive framework established in this work could help improve the non-local form factors needed as input for a robust interpretation of $B\to (P,V){\ell }^{+}{\ell }^{-}$ decays.

    hep-phhep-exnucl-thJHEP(2024)·22 citations
14. 14*

    Fusing photons into diphoton resonances at Belle II and beyond

    Francesca Acanfora🇩🇪 · Roberto Franceschini🇮🇹 · Alessio Mastroddi🇮🇹 · Diego Redigolo🇮🇹

    We propose a new search for a diphoton resonance in the $e^{+}{e}^{-}+\gamma \gamma$ final state at Belle II that improves the expected reach compared to the $\gamma +\gamma \gamma$ channel in most of the available mass range. For simplicity we show our results in the simple parameter space of an ALP coupled solely to Standard Model photons. In addition, we show how an extension of the forward coverage of Belle II, or another similar experiment at the high intensity frontier, could improve the reach in our channel. We show that such a forward extension can be advantageous even with a loss of a factor 100 in luminosity compared to Belle II.

    hep-phJHEP(2024)·9 citations
15. 15*

    Thermodynamics of Continuous Spin photons

    Philip Schuster🇺🇸 · Gowri Sundaresan🇺🇸 · Natalia Toro🇺🇸

    Special relativity allows massless particles to have states of different integer (or half-integer) helicities that mix under boosts, much like the spin-states of a massive particle. Such massless particles are known as continuous spin particles (CSPs), a term coined by Wigner, and they are notable for their infinite tower of spin polarizations. The mixing under boosts is controlled by a spin-scale $\rho$ with units of momentum. Normally, we assume $\rho =0$. The interactions of CSPs are known to satisfy certain simple properties, one of which is that the $\rho \to 0$ limit generically recovers familiar interactions of massless scalars, photons, or gravitons, with all other polarizations decoupling in this limit. Thus, one can ask if the photon of the Standard Model is a CSP at small but non-zero $\rho$. One concern about this possibility -- originally raised by Wigner -- is that the infinite tower of polarizations could pose problems for thermodynamics. To address this question, we study the thermal evolution of a CSP photon gas coupled to isothermal matter, across CSP helicity modes and phase space. We find that the structure of the interactions dictated by Lorentz symmetry imply well behaved thermodynamics. When the CSP photon's interactions to charged matter are turned on, the primary $h=\pm 1$ helicity modes thermalize quickly, while the other modes require increasingly long time-scales to thermalize, set by powers of $T/\rho$. In familiar thermal systems, the CSP photon behaves like the QED photon with small $\rho$- and time- dependent corrections to its effective relativistic degrees of freedom. Sizable departures from familiar thermal behavior arise at energy scales comparable to $\rho$ and could have testable experimental consequences.

    hep-phhep-thPRD(2025)·15 citations
16. 16*

    LHC EFT WG Note: SMEFT predictions, event reweighting, and simulation

    Alberto Belvedere🇩🇪 · Saptaparna Bhattacharya (ed.)🇺🇸 · Giacomo Boldrini🇫🇷 · Suman Chatterjee🇦🇹 · Alessandro Calandri🇨🇭 · Sergio Sánchez Cruz🇨🇭 · Jennet Dickinson🇺🇸 · Franz J. Glessgen🇨🇭 · Reza Goldouzian🇺🇸 · Alexander Grohsjean🇩🇪 · Laurids Jeppe🇩🇪 · Charlotte Knight (ed.)🇬🇧 and 7 other authors

    This note gives an overview of the tools for predicting expectations in the Standard Model effective field theory (SMEFT) at the tree level and one loop available through event generators. Methods of event reweighting, the separate simulation of squared matrix elements, and the simulation of the full SMEFT process are compared in terms of statistical efficacy and potential biases.

    hep-phhep-exSciPost Phys.Comm.Rep.(2024)·14 citations
17. 17*

    Gluon radiation inside a flowing medium

    Matvey V. Kuzmin🇷🇺 · Xoán Mayo López🇪🇸

    We compute the spectrum of gluons emitted by a highly energetic quark inside a flowing QCD medium, focusing on the soft gluon limit at first order in the opacity expansion. Specifically, we derive the leading energy-suppressed corrections to the double differential final parton distribution, and show that they are substantial for both static and flowing matter. In particular, we demonstrate that the corrections due to the transverse flow become large even at moderate energies and flow velocities, affecting drastically both the shape and magnitude of the spectrum. We observe that the final transverse momentum of the emitted gluon tends to align along the flow direction, resulting in a non-trivial azimuthal distribution. These results can be directly implemented into the estimation of multiple observables to get a better understanding of the jet-medium interaction processes in HICs.

    hep-phnucl-thPRD(2026)·17 citations
18. 18*

    High-energy Neutrino Emission from NGC 1068 by Outflow-cloud Interactions

    Yong-Han Huang🇺🇸 · Kai Wang🇨🇳 · Zhi-Peng Ma

    As the hottest high-energy neutrino spot, NGC 1068 has received much attention in recent years. Here we focus on the central region of the active galactic nuclei (AGN) and propose an outflow-cloud interaction model that could probably explain the observed neutrino data. Considering the accretion process adjacent to the central supermassive black hole (SMBH) of NGC 1068, strong outflows will be generated, which will likely interact with surrounding clouds floating in the corona region. Particles carried by the outflow will be accelerated to very high energy by the shocks forming during the outflow-cloud interactions. For the accelerated high-energy protons, $p\gamma$ interactions with the background photon field of the corona and disk and $pp$ interaction with the surrounding gas will produce considerable high-energy $\gamma$-rays and neutrino. However, because of the extremely dense photon fields in the corona and disk, the newly generated $\gamma$-rays will be significantly attenuated through the $\gamma \gamma$ absorptions. In our scenario, the expected GeV-TeV $\gamma$-ray emission will be suppressed to a much lower level than the neutrino emission, consistent with the observational characteristics of NGC 1068, while the generated 1-30\,TeV neutrino flux can fit the IceCube data very well.

    ↳ astro-ph.HEhep-ph7 citations
19. 19*

    A Collaborative Explanation of Cosmic Ray Spectrum Based on the Gluon Condensation Model

    Jintao Wu🇨🇳 · Jianhong Ruan🇨🇳

    Based on the Gluon Condensation (GC) model, the relationship between the spectra of electrons, $\gamma$ rays, and neutrinos in cosmic rays can be deduced. It has been found that these particles share the same parameter, ${\beta }_p$, and have an identical GC threshold values. This paper explores the connection between the second excess spectra of electron and the spectra of gamma rays and neutrinos. According to the observed gamma-ray data, it is suggested that the source LHAASO J2108+5157 might contribute to the second excess of electron.

    ↳ astro-ph.HEhep-ph1 citation
20. 20*

    Clocking the End of Cosmic Inflation

    Pierre Auclair🇧🇪 · Baptiste Blachier🇧🇪 · Christophe Ringeval🇧🇪

    Making observable predictions for cosmic inflation requires determining when the wavenumbers of astrophysical interest today exited the Hubble radius during the inflationary epoch. These instants are commonly evaluated using the slow-roll approximation and measured in e-folds $\Delta N=N-N_{\mathrm{end}}$, in reference to the e-fold $N_{\mathrm{end}}$ at which inflation ended. Slow roll being necessarily violated towards the end of inflation, both the approximated trajectory and $N_{\mathrm{end}}$ are determined at, typically, one or two e-folds precision. Up to now, such an uncertainty has been innocuous, but this will no longer be the case with the forthcoming cosmological measurements. In this work, we introduce a new and simple analytical method, on top of the usual slow-roll approximation, that reduces uncertainties on $\Delta N$ to less than a tenth of an e-fold.

    ↳ astro-ph.COgr-qchep-phhep-thJCAP(2024)·8 citations
21. 21*

    Exact solutions for differentially rotating galaxies in general relativity

    Marco Galoppo🇳🇿 · David L. Wiltshire🇳🇿

    Two classes of stationary axisymmetric solutions of Einstein's equations for isolated differentially rotating matter sources are presented. The asymptotic regime is extracted, with attention to quasilocal gravitational energy, shear and angular momentum related by the Raychaudhuri equation. At outer boundaries the quasilocal angular momentum and energy densities vanish, defining novel geometric structures - the vortex surface and the rotosurface. Solutions with a rotosurface present a new notion of asymptotic flatness: vorticity, shear and Kretschmann scalars vanish at a finite radial distance from the symmetry centre. Synthetic rotation curves for the Milky Way are presented, fit to GAIA-DR3 data, and potential astrophysical signatures are suggested. Whether or not abundant collisionless dark matter exists, the new solutions very strongly support suggestions that the phenomenology of galactic rotation curves be fundamentally reconsidered, for consistency with general relativity.

    ↳ gr-qcastro-ph.COastro-ph.GAhep-ph+113 citations
22. 22*

    Covariant quantum field theory of tachyons is unphysical

    Krzysztof Jodłowski🇰🇷

    Tachyons have fascinated generations of physicists due to their peculiar behavior, but they did not solve any real physical problem. This may have changed with the recent works of Dragan et al., who have shown that superluminal observers may be related to the foundations of quantum mechanics (QM) because they require introducing non-determinism and wave-like behavior at the fundamental level. Unfortunately, we show that the tachyon quantum field theory proposed as a part of this program is not quantum since the tachyon field commutes at all points and the canonical commutations relations of a quantum scalar field are not satisfied. We also discuss other authors' theories, e.g., we show that the Dhar-Sudarshan's formula for the Feynman propagator violates unitarity, and we apply the LSZ formalism to tachyons for the first time, where we find that one cannot prove the LSZ asymptotic condition just by replacing plane waves with wavepackets.

    ↳ quant-phgr-qchep-phhep-thPRD(2024)·9 citations
23. 23*

    Black holes with electroweak hair

    Romain Gervalle🇫🇷 · Mikhail S. Volkov🇫🇷

    We construct static and axially symmetric magnetically charged hairy black holes in the gravity-coupled Weinberg-Salam theory. Large black holes merge with the Reissner-Nordström (RN) family, while the small ones are extremal and support a hair in the form of a ring-shaped electroweak condensate carrying superconducting W-currents and up to $22\%$ of the total magnetic charge. The extremal solutions are asymptotically RN with a mass {\it below} the total charge, $M<|Q|$, due to the negative Zeeman energy of the condensate interacting with the black hole magnetic field. Therefore, they cannot decay into RN black holes. As their charge increases, they show a phase transition when the horizon symmetry changes from spherical to oblate. At this point they have the mass typical for planetary size black holes of which $\approx 11\%$ is stored in the hair. Being obtained within a well-tested theory, our solutions are expected to be physically relevant.

    ↳ hep-thgr-qchep-phPRL(2024)·23 citations
24. 24*

    Spin Statistics and Surgeries of Topological Solitons in QCD Matter in Magnetic Field

    Yuki Amari🇯🇵 · Muneto Nitta🇯🇵 · Ryo Yokokura🇯🇵

    The ground state of QCD with two flavors (up and down quarks) at finite baryon density in sufficiently strong magnetic field is in a form of either a chiral soliton lattice(CSL), an array of solitons stacked along the magnetic field, or a domain-wall Skyrmion phase in which Skyrmions are spontaneously created on top of the CSL In the latter, one 2D (baby) Skyrmion in the chiral soliton corresponds to two 3D Skyrmions (baryons) in the bulk. In this paper, we study spin statistics of topological solitons by using the following two methods: the conventional Witten's method by embedding the pion fields of two flavors into those of three flavors with the Wess-Zumino-Witten (WZW) term, and a more direct method by using the two-flavor WZW term written in terms of a spin structure. We find that a chiral soliton of finite quantized size called a pancake soliton and a hole on a chiral soliton are fermions or bosons depending on odd or even quantizations of their surface areas, respectively, and a domain-wall Skyrmion is a boson. We also propose surgeries of topological solitons: a domain-wall Skyrmion (boson) can be cut into a pancake soliton (fermion) and a hole (fermion), and a chiral soliton without Skyrmions can be cut into a pancake soliton (fermion) and a hole (fermion).

    ↳ hep-thhep-phJHEP(2025)·16 citations
25. 25*

    Hydrodynamic-like behaviour of glasma

    Margaret E. Carrington🇨🇦 · Stanislaw Mrowczynski🇵🇱 · Jean-Yves Ollitrault🇫🇷

    At the earliest stage of ultrarelativistic heavy-ion collisions the produced matter is a highly populated system of gluons called glasma which can be approximately described in terms of classical chromodynamic fields. Although the system's dynamics is governed by Yang-Mills equations, glasma evolution is shown to strongly resemble hydrodynamic behaviour.

    ↳ nucl-thhep-phPRC(2024)·10 citations
26. 26*

    Neutrino mass bounds from DESI 2024 are relaxed by Planck PR4 and cosmological supernovae

    Itamar J. Allali🇺🇸 · Alessio Notari🇪🇸

    The recent DESI 2024 Baryon Acoustic Oscillations (BAO) measurements combined with the CMB data from the Planck 18 PR3 dataset and the Planck PR4+ACT DR6 lensing data, with a prior on the sum of the neutrino masses $\sum m_{\nu }>0$, leads to a strong constraint, $\sum m_{\nu }<0.072$ eV, which would exclude the inverted neutrino hierarchy and put some tension on even the standard hierarchy. We show that actually this bound gets significantly relaxed when combining the new DESI measurements with the HiLLiPoP+LoLLiPoP likelihoods, based on the Planck 2020 PR4 dataset, and with supernovae datasets. We note that the fact that neutrino masses are pushed towards zero, and even towards negative values, is known to be correlated with the so-called $A_L$ tension, a mismatch between lensing and power spectrum measurements in the Planck PR3 data, which is reduced by HiLLiPoP+LoLLiPoP to less than 1$\sigma$. We find $\sum m_{\nu }<0.1$ eV and $\sum m_{\nu }<0.12$ eV, with the supernovae Pantheon+ and DES-SN5YR datasets respectively. The shift caused by these datasets is more compatible with the expectations from neutrino oscillation experiments, and both the normal and inverted hierarchy scenarios remain now viable, even with the $\sum m_{\nu }>0$ prior. Finally, we analyze neutrino mass bounds in an extension of $\Lambda$CDM that addresses the $H_0$ tension, with extra fluid Dark Radiation, finding that in such models bounds are further relaxed and the posterior probability for $\sum m_{\nu }$ begins to exhibit a peak at positive values.

    ↳ astro-ph.COhep-phJCAP(2024)·59 citations
27. 27*

    Two-Loop Spacelike Splitting Amplitude for N=4 Super-Yang-Mills Theory

    Johannes Henn🇩🇪 · Rourou Ma🇨🇳 · Yongqun Xu🇨🇳 · Kai Yan🇨🇳 · Yang Zhang🇨🇳 · Hua Xing Zhu🇨🇳

    The study of collinear behavior for gauge theories in the spacelike region is of great phenomenological and theoretical importance. We analytically calculate the two-loop spacelike splitting amplitude for the full color N=4 Super-Yang-Mills theory. The result is derived by two complementary methods starting from the known amplitude: one is based on a discontinuity analysis, while the other one is based on analytic continuation. Our result explicitly shows terms that violate naive factorization. However we show that factorization is restored at the level of color-summed unpolarized squared amplitudes at next-to-next-to-next-to leading order. We conjecture that the two-loop tripole terms in the generalized splitting amplitudes in QCD are identical to what we obtain in N=4 super Yang-Mills theory.

    ↳ hep-thhep-phPRD(2025)·22 citations
28. 28*

    The Tropical Geometry of Subtraction Schemes

    Giulio Salvatori🇩🇪

    We study the construction of local subtraction schemes through the lenses of tropical geometry. We focus on individual Feynman integrals in parametric presentation, and think of them as particular instances of Euler integrals. We provide a necessary and sufficient condition for a combination of Euler integrands to be locally finite, i.e. to be expandable as a Taylor series in the exponent variables directly under sign of integration. We use this to construct a local subtraction scheme that is applicable to a class of Euler integrals that satisfy a certain geometric property. We apply this to compute the Laurent expansion in the dimensional regulator $ϵ$ of various Feynman integrals involving both UV and IR singularities, as well as to generalizations of Feynman integrals that arise in effective field theories and in phase-space integrations, for which we provide new analytic results.

    ↳ hep-thhep-phmath.AG23 citations
29. 29*

    On small Dirac Neutrino Masses in String Theory

    Gonzalo F. Casas🇪🇸 · Luis E. Ibáñez🇪🇸 · Fernando Marchesano🇪🇸

    We study how tiny Dirac neutrino masses consistent with experimental constraints can arise in string theory SM-like vacua. We use as a laboratory 4d $\mathcal{N}=1$ type IIA Calabi--Yau orientifold compactifications, and in particular recent results on Yukawa couplings at infinite field-space distance. In this regime we find Dirac neutrino masses of the form $m_{\nu }\simeq g_{\nu }⟨H⟩$, with $g_{\nu }$ the gauge coupling of the massive $U(1)$ under which the right-handed neutrinos ${\nu }_R$ are charged, and which should be in the range $g_{\nu }\simeq 10^{-14}-10^{-12}$ to reproduce neutrino data. The neutrino mass suppression occurs because the right-handed neutrino kinetic term behaves as $K_{\nu \nu }\simeq 1/g_{\nu }^2$. At the same time a tower of ${\nu }_R$-like states appears with characteristic scale $m_0\simeq g_{\nu }^2{M}_{\mathrm{P}}\simeq 0.1-500$ eV, in agreement with Swampland expectations. Two large hidden dimensions only felt by the ${\nu }_R$ sector arise at the same scale, while the string scale is around $M_s\simeq g_{\nu }{M}_{\mathrm{P}}\simeq 10-700$ TeV. Some phenomenological implications and model building challenges are described. As a byproduct, independently of the neutrino issue, we argue that a single large dimension in the context of SM-like type IIA Calabi--Yau orientifolds leads to too small Yukawa couplings for quarks and charged leptons.

    ↳ hep-thhep-phJHEP(2025)·17 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.