Wed·Aug 12, 2020Wednesday·August 12, 2020

1. 01*

   A Minimal Approach to Baryogenesis via Affleck-Dine and Inflaton Mass Terms

   Amy Lloyd-Stubbs🇬🇧 · John McDonald🇬🇧

   We present a minimal approach to the generation of the baryon ($B$) asymmetry of the Universe, in which the asymmetry is generated in a complex inflaton condensate via $B$-violating quadratic inflaton potential terms using the Affleck-Dine (AD) mechanism. We show that the $B$-violating quadratic mass terms create an oscillating asymmetry in the complex inflaton condensate at late times. The final asymmetry transferred to the Standard Model sector at reheating is naturally reduced to the magnitude of the observed $B$ asymmetry by the effect of averaging over the $B$ oscillations. This approach to baryogenesis can easily be realised in a wide range of inflation models. We also show that AD baryogenesis via inflaton mass terms is free of the tuning of field dynamics required by the conventional AD mechanism.

   hep-phastro-ph.COastro-ph.HEhep-thPRD(2021)·32 citations
2. 02*

   Transverse spin sum rule of the proton

   Xiangdong Ji🇺🇸 · Feng Yuan🇺🇸

   The transversely-polarized state of a proton with arbitrary momentum is not an eigenstate of transverse angular momentum operator. The latter does not commute with the QCD Hamiltonian. However, the expectation value of the transverse angular momentum in the state is well-defined and grows proportionally to the energy of the particle. The transverse spin content of the proton is analyzed in terms of the QCD angular momentum structure. In particular, we reconfirm that the generalized parton distributions $H+E$ provide transverse orbital angular momentum densities of quarks and gluons in the infinite momentum frame.

   hep-phhep-latnucl-thPLB(2020)·16 citations
3. 03*

   Inclusive prompt photon-jet correlations as a probe of gluon saturation in electron-nucleus scattering at small $x$

   Isobel Kolbé🇺🇸 · Kaushik Roy🇺🇸 · Farid Salazar🇺🇸 · Bjoern Schenke🇺🇸 · Raju Venugopalan🇺🇸

   We compute the differential cross-section for inclusive prompt photon$+$quark production in deeply inelastic scattering of electrons off nuclei at small $x$ ($e+A$ DIS) in the framework of the Color Glass Condensate effective field theory. The result is expressed as a convolution of the leading order (in the strong coupling ${\alpha }_{\mathrm{s}}$) impact factor for the process and universal dipole matrix elements, in the limit of hard photon transverse momentum relative to the nuclear saturation scale $Q_{s,A}(x)$. We perform a numerical study of this process for the kinematics of the Electron-Ion Collider (EIC), exploring in particular the azimuthal angle correlations between the final state photon and quark. We observe a systematic suppression and broadening pattern of the back-to-back peak in the relative azimuthal angle distribution, as the saturation scale is increased by replacing proton targets with gold nuclei. Our results suggest that photon+jet final states in inclusive $e+A$ DIS at high energies are in general a promising channel for exploring gluon saturation that is complementary to inclusive and diffractive dijet production. They also provide a sensitive empirical test of the universality of dipole matrix elements when compared to identical measurements in proton-nucleus collisions. However because photon+jet correlations at small $x$ in EIC kinematics require jet reconstruction at small $k_{\perp }$, it will be important to study their feasibility relative to photon-hadron correlations.

   hep-phnucl-thJHEP(2021)·39 citations
4. 04*

   Gravitational formfactors of the $\rho$ meson in QCD sum rules

   T. M. Aliev · T. Barakat · K. Şimşek

   By using the quark part of the energy-momentum tensor current, the gravitational formfactors of the $\rho$ meson are calculated within the light-cone sum rules method. In the considered version, the energy-momentum tensor current is not conserved and as a result, there appear nine formfactors, six (three) of which correspond to the conservation (nonconservation) of the energy-momentum tensor current. We also compare our results with the one existing in the literature.

   hep-phPhys. Rev. D 103, 054001 (2021)
5. 05*

   Fermi-ball dark matter from a first-order phase transition

   Jeong-Pyong Hong🇰🇷 · Sunghoon Jung🇰🇷 · Ke-Pan Xie🇰🇷

   We propose a novel dark matter (DM) scenario based on a first-order phase transition in the early universe. If dark fermions acquire a huge mass gap between true and false vacua, they can barely penetrate into the new phase. Instead, they get trapped in the old phase and accumulate to form macroscopic objects, dubbed Fermi-balls. We show that Fermi-balls can explain the DM abundance in a wide range of models and parameter space, depending most crucially on the dark-fermion asymmetry and the phase transition energy scale (possible up to the Planck scale). They are stable by the balance between fermion's quantum pressure against free energy release, hence turn out to be macroscopic in mass and size. However, this scenario generally produces no detectable signals (which may explain the null results of DM searches), except for detectable gravitational waves (GWs) for electroweak scale phase transitions; although the detection of such stochastic GWs does not necessarily imply a Fermi-ball DM scenario.

   hep-phastro-ph.COPRD(2020)·121 citations
6. 06*

   Flavon Magneto-Baryogenesis

   Fatemeh Elahi🇮🇷 · Shiva Rostam Zadeh🇮🇷

   In this paper, we explore the evolution of baryon asymmetry as well as the hypermagnetic field in the early universe with an assumption that the flavon of the Froggatt-Nielsen carries an asymmetry. Through the decay of the flavon to Standard Model fermions, this asymmetry is transferred to fermions, where the right-handed electron keeps its asymmetry while its Yukawa interaction is out of thermal equilibrium. Through the existence of the flavon, we can ensure that the freezing-in temperature of the right-handed electron is closer to the electroweak phase transition than the Standard cosmology scenario. With this trick, the asymmetry in the right-handed electron is saved for a longer time. Moreover, the injection of the asymmetry to the right-handed electron is gradual, which helps the preservation of the asymmetry in the right-handed sector significantly. Due to the intimate relationship between fermion number violation and the helicity of the hypermagnetic field, some of the asymmetry is used to amplify the hypermagnetic field which itself helps to preserve the remnant asymmetry through keeping the Yukawa processes out of thermal equilibrium. We find the sweet region of the parameter space that can produce the right asymmetry in the baryons while generating a large hypermagnetic field by the time of the electroweak phase transition.

   hep-phPRD(2020)·9 citations
7. 07*

   Looking for a vector charmonium-like state $Y$ in $e^{+}{e}^{-}\to \bar{D}{D}_1(2420)+c.c.$

   Jian-Rong Zhang🇨🇳

   Inspired by the first observation of a vector charmonium-like state $Y(4626)$ decaying to a meson pair $D_s^{+}{D}_{s1}(2536{)}^{-}$, which could be viewed as a $P$-wave scalar-scalar $[cs][\bar{c}\bar{s}]$ tetraquark state, we predict a potential vector charmonium-like state $Y$ with $P$-wave scalar-scalar $[cq][\bar{c}\bar{q}]$ configuration. The corresponding mass spectrum of $Y$ state is calculated to be $4.33_{-0.23}^{+0.16}\text{mbox}GeV$ in the framework of QCD sum rules. We suggest that the predicted $Y$ state could be looked for in an open-charm $e^{+}{e}^{-}\to \bar{D}{D}_1(2420)+c.c.$ process.

   hep-phhep-exPRD(2020)·1 citation
8. 08*

   Neutral-current background induced by atmospheric neutrinos at large liquid-scintillator detectors: I. model predictions

   Jie Cheng🇨🇳 · Yu-Feng Li🇨🇳 · Liang-Jian Wen🇨🇳 · Shun Zhou🇨🇳

   The experimental searches for diffuse supernova neutrino background and proton decay in next-generation large liquid-scintillator (LS) detectors are competitive with and complementary to those in the water-Cherenkov detectors. In this paper, we carry out a systematic study of the dominant background induced by atmospheric neutrinos via their neutral-current (NC) interactions with the ${}^{12}\mathrm{C}$ nuclei in the LS detectors. The atmospheric neutrino fluxes at the location of Jiangmen Underground Neutrino Observatory (JUNO) are used, as the JUNO detector is obviously a suitable representative for future LS detectors. Then, we implement the sophisticated generators \texttt{GENIE} and \texttt{NuWro} to simulate the neutrino interactions with the carbon nuclei, and the package \texttt{TALYS} to deal with the deexcitations of final-state nuclei. Finally, the event rates for the production of additional nucleons, $\gamma$'s, $\alpha$'s, pions and kaons are obtained and categorized, and the systematic uncertainty of the NC background represented by a variety of data-driven nuclear models is estimated. The implications of the NC background from atmospheric neutrinos for the detection of diffuse supernova neutrino background and proton decay are also discussed.

   hep-phastro-ph.HEhep-exnucl-thPRD(2021)·27 citations
9. 09*

   Dark Matter EFT, the Third -- Neutrino WIMPs

   Ingolf Bischer🇩🇪 · Tilman Plehn🇩🇪 · Werner Rodejohann🇩🇪

   Sterile neutrinos coupling only to third-generation fermions are attractive dark matter candidates. In an EFT approach we demonstrate that they can generate the observed relic density without violating constraints from direct and indirect detection. Such an EFT represents a gauged third-generation $B-L$ model, as well as third-generation scalar or vector leptoquarks. LHC measurements naturally distinguish the different underlying models.

   hep-phSciPost Phys.(2021)·6 citations
10. 10*

    Coherence and mixedness of neutrino oscillations in a magnetic field

    P. Kurashvili🇵🇱 · L. Chotorlishvili🇩🇪 · K. A. Kouzakov🇷🇺 · A. I. Studenikin🇷🇺

    The radical departure from classical physics implies quantum coherence, i.e., coherent superposition of eigenstates of Hermitian operators with a discrete spectrum. In resource theory, quantum coherence is a resource for quantum operations. Typically the stochastic phenomenon induces decoherence effects. However, in the present work, we prove that nonunitary evolution leads to the generation of quantum coherence in some cases. Specifically, we consider the neutrino propagation in the dissipative environment, namely in a magnetic field with a stochastic component, and focus on neutrino flavor, spin and spin-flavor oscillations. We present exact analytical results for quantum coherence in neutrino oscillations quantified in terms of the relative entropy. Starting from an initial zero coherence state, we observe persistent oscillations of coherence during the dissipative evolution. We found that after dissipative evolution, the initial spin-polarized state entirely thermalizes, and in the final steady state, the spin-up/down states have the same probabilities. On the other hand, neutrino flavor states also thermalize, byt the populations of two flavor states do not equate to each other. The initial flavor still dominates in the final steady state

    hep-phEPJC(2021)·13 citations
11. 11*

    Next-to-Next-to-Leading-Order Radiative Corrections to $e^{+}{e}^{-}\to {\chi }_{cJ}+\gamma$ at $B$ factory

    Wen-Long Sang🇨🇳 · Feng Feng🇨🇳 · Yu Jia🇨🇳

    Within the nonrelativistic QCD (NRQCD) factorization framework, we have computed the $\mathcal{O}({\alpha }_s^2)$ corrections to the exclusive production of $P$-wave spin-triplet charmonia ${\chi }_{cJ}(J=0,1,2)$ accompanied by a hard photon at $B$ factories. For the first time, we have explicitly verified the validity of NRQCD factorization for exclusive $P$-wave quarkonium production at two-loop order. Unlike the ${\chi }_{cJ}$ electromagnetic decay processes, the $\mathcal{O}({\alpha }_s^2)$ corrections are found to be smaller than the $\mathcal{O}({\alpha }_s)$ corrections in all three channels $e^{+}{e}^{-}\to {\chi }_{c0,1,2}+\gamma$. In particular, the $\mathcal{O}({\alpha }_s^2)$ corrections appear moderate for ${\chi }_{c1}$ case, and insignificant for ${\chi }_{c0}$. In addition, the next-to-next-to-leading order (NNLO) predictions for the production rates of ${\chi }_{c0,1}+\gamma$ are insensitive to the renormalization and factorization scales. All of these features may indicate that perturbative expansion in these two channels exhibits a decent convergence behavior. By contrast, both the $\mathcal{O}({\alpha }_s)$ and $\mathcal{O}({\alpha }_s^2)$ corrections to the ${\chi }_{c2}+\gamma$ production cross section are sizable, which even reduces the Born order cross section by one order of magnitude after including the NNLO perturbative correction. Taking the values of the long-distance NRQCD matrix elements from nonrelativistic potential model, our prediction to ${\chi }_{c1}+\gamma$ production rate is consistent with the recent {\tt Belle} measurement. The NNLO predictions for the ${\chi }_{c0,2}+\gamma$ production rates are much smaller than that for ${\chi }_{c1}+\gamma$, which seems to naturally explain why the $e^{+}{e}^{-}\to {\chi }_{c0,2}+\gamma$ channels have escaped experimental detection to date.

    hep-phJHEP(2020)·22 citations
12. 12*

    Remarks on an anomalous triple gauge boson couplings

    Patricio Gaete🇨🇱 · J. A. Helayël-Neto🇧🇷 · L. P. R. Ospedal🇧🇷

    We address the effect of an anomalous triple gauge boson couplings on a physical observable for the electroweak sector of the Standard Model, when the $SU(2{)}_L\otimes U(1{)}_Y$ symmetry is spontaneously broken by the Higgs mechanism to $U(1{)}_{em}$. Our calculation is done within the framework of the gauge-invariant, but path-dependent variable formalism which is alternative to the Wilson loop approach. Our result shows that the interaction energy is the sum of a Yukawa and a linear potential, leading to the confinement of static probe charges. The point we wish to emphasize, however, is that the anomalous triple gauge boson couplings ($Z\gamma \gamma$) contributes to the confinement for distances on the intranuclear scale.

    hep-phhep-thAdv.High Energy Phys.(2021)·5 citations
13. 13*

    Energy Flow in Particle Collisions

    Eric M. Metodiev🇺🇸

    In this thesis, I introduce a new bottom-up approach to quantum field theory and collider physics, beginning from the observable energy flow: the energy distribution produced by particle collisions. First, I establish a metric space for collision events by comparing their energy flows. I unify many ideas spanning multiple decades, such as observables and jets, as simple geometric objects in this new space. Second, I develop a basis of observables by systematically expanding in particle energies and angles, encompassing many existing observables and uncovering new analytic structures. I highlight how the traditional criteria for theoretical calculability emerge as consistency conditions, due to the redundancy of describing an event using particles rather than its energy flow. Finally, I propose a definition of particle type, or flavor, which makes use of only observable information. This definition requires refining the notion of flavor from a per-event label to a statistical category, and I showcase its direct experimental applicability at colliders. Throughout, I synthesize concepts from particle physics with ideas from statistics and computer science to expand the theoretical understanding of particle interactions and enhance the experimental capabilities of collider data analysis techniques.

    hep-phhep-th0 citations
14. 14*

    Heavy axion-like particles and core-collapse supernovae: constraints and impact on the explosion mechanism

    Giuseppe Lucente (Bari Univ.)🇮🇹 · Pierluca Carenza (Bari Univ. and INFN Bari)🇮🇹 · Tobias Fischer (Wroclaw Univ.)🇵🇱 · Maurizio Giannotti (Barry Univ.)🇺🇸 · Alessandro Mirizzi (Bari Univ. and INFN Bari)🇮🇹

    Heavy axion-like particles (ALPs), with masses $m_a\gtrsim 100$ keV, coupled with photons, would be copiously produced in a supernova (SN) core via Primakoff process and photon coalescence. Using a state-of-the-art SN model, we revisit the energy-loss SN 1987A bounds on axion-photon coupling. Moreover, we point out that heavy ALPs with masses $m_a\gtrsim 100$ MeV and axion-photon coupling $g_{a\gamma }\gtrsim 4\times 10^{-9}$ GeV${}^{-1}$ would decay into photons behind the shock-wave producing a possible enhancement in the energy deposition that would boost the SN shock revival.

    hep-phastro-ph.HEJCAP(2020)·136 citations
15. 15*

    Medium-induced fragmentation and equilibration of highly energetic partons

    Soeren Schlichting🇩🇪 · Ismail Soudi🇩🇪

    We investigate the energy loss and equilibration of highly energetic particles/jets inside a QCD medium. Based on an effective kinetic description of QCD, including $2\leftrightarrow 2$ elastic processes, radiative $1\leftrightarrow 2$ processes, as well as the back-reaction of jet constituents onto the thermal medium, we describe the in-medium evolution of jets from the energy scale of the jet $\sim E$ all the way to the medium scale $\sim T$. While elastic processes and back-reaction are important to describe the equilibration of soft fragments of the jet, we find that the energy loss is dominated by an inverse turbulent cascade due to successive radiative branchings, which has interesting implications for the energy spectra and chemistry of jet fragments.

    hep-phnucl-thJHEP(2021)·53 citations
16. 16*

    Renormalizable $SO(10)$ GUT with Suppressed Dimension-5 Proton Decays

    Naoyuki Haba🇯🇵 · Yukihiro Mimura🇯🇵 · Toshifumi Yamada🇯🇵

    We study a renormalizable SUSY $SO(10)$ GUT model where the Yukawa couplings of single $10$, single $\overline{126}$ and single $120$ fields, $Y_{10},Y_{126},Y_{120}$, account for the quark and lepton Yukawa couplings and the neutrino mass. We pursue the possibility that $Y_{10},Y_{126},Y_{120}$ reproduce the correct quark and lepton masses, CKM and PMNS matrices and neutrino mass differences, and at the same time suppress dimension-5 proton decays (proton decays via colored Higgsino exchange) through their texture, so that the soft SUSY breaking scale can be reduced as much as possible without conflicting the current experimental bound on proton decays. We perform a numerical search for such a texture, and investigate implications of that texture on unknown neutrino parameters, the Dirac CP phase of PMNS matrix, the lightest neutrino mass and the $(1,1)$-component of the neutrino mass matrix in the charged lepton basis. Here we concentrate on the case when the active neutrino mass is generated mostly by the Type-2 seesaw mechanism, in which case the correlation between the suppression of dimension-5 proton decays and the neutrino parameters is expected to be most direct.

    hep-phPTEP(2021)·3 citations
17. 17*

    $B_{d,s}^0\to f_1{f}_1$ decays with $f_1(1285)-f_1(1420)$ mixing in the perturbative QCD approach

    Zewen Jiang🇨🇳 · De-Hua Yao🇨🇳 · Zhi-Tian Zou🇨🇳 · Xin Liu🇨🇳 · Ying Li🇨🇳 · Zhen-Jun Xiao🇨🇳

    We investigate the $B_{d,s}^0\to f_1{f}_1$ decays in the framework of perturbative QCD(PQCD) approach with a referenced value ${\varphi }_{f_1}\sim 24^{\circ }$. Here, $f_1$ denotes the axial-vector mesons $f_1(1285)$ and $f_1(1420)$ with mixing angle ${\varphi }_{f_1}$ in the quark-flavor basis. The observables such as branching ratios, direct CP violations, and polarization fractions of the $B_s^0\to f_1{f}_1$ decays are predicted for the first time. We find that: (i) the almost pure penguin modes $B_s^0\to f_1{f}_1$ have large branching ratios in the order of $10^{-6}\sim 10^{-5}$ due to the Cabibbo-Kobayashi-Maskawa enhancement and generally constructive interferences between the amplitudes of $B_s^0\to f_n{f}_s$ and $B_s^0\to f_s{f}_s$ with $f_n$ and $f_s$ being the quark-flavor states of $f_1$ mesons; (ii) The observables receive important contributions from the weak annihilation diagrams in the PQCD approach. In particular, without the annihilation contributions, the $B_s^0\to f_1(1420)f_1(1420)$ branching ratio will decrease about 81% and its longitudinal polarization fraction will reduce around 43%. And (iii) the dependence of the $B_{d,s}^0\to f_1{f}_1$ decay rates on ${\varphi }_{f_1}$ exhibits some interesting line shapes, whose confirmations would be helpful to constrain the determination of ${\varphi }_{f_1}$ inversely. All the PQCD predictions await for the (near) future examinations at Large Hadron Collider beauty and/or Belle-II experiments to further understand the properties of the axial-vector mesons and the perturbative dynamics released from the considered decay modes.

    hep-phPRD(2020)·5 citations
18. 18*

    Towards reconciling the holographic and lattice descriptions of radially excited hadrons

    S. S. Afonin🇷🇺

    Within the framework of AdS/QCD models, the spectra of radially excited hadrons are identified with towers of Kaluza-Klein (KK) states in a putative dual theory. The infinite number of KK states is indispensable to provide correct high energy asymptotics of correlation functions in QCD. It is known, however, that the KK modes of dual theory must be qualitatively different from real hadrons. And what is more important, the radially excited states appear in lattice calculations not as "excitations" of some ground state, but rather as independent states coupled to higher dimensional QCD operators - the larger is a basis of interpolating operators, the larger set of states can be resolved. A question arises whether it is possible to reconcile the holographic and lattice descriptions of radially excited hadrons? We propose a new phenomenological "consistency test" for bottom-up holographic models: If the KK spectrum of massive 5D fields corresponding to higher dimensional operators in QCD coincides with the conventional radial KK spectrum, then the holographic KK states can be identified with real excited mesons in the large-Nc limit of QCD - as in the lattice QCD, they become a superposition of several states interpolated by operators of different canonical dimensions. We demonstrate that the Soft Wall holographic model passes this test while the Hard Wall model does not.

    hep-phhep-thEPJC(2020)·13 citations
19. 19*

    Exciting Prospects for Detecting Late-Time Neutrinos from Core-Collapse Supernovae

    Shirley Weishi Li🇺🇸 · Luke F. Roberts🇺🇸 · John F. Beacom🇺🇸

    The importance of detecting neutrinos from a Milky Way core-collapse supernova is well known. An under-studied phase is proto-neutron star cooling. For SN 1987A, this seemingly began at about 2 s, and is thus probed by only 6 of the 19 events (and only the ${\bar{\nu }}_e$ flavor) in the Kamiokande-II and IMB detectors. With the higher statistics expected for present and near-future detectors, it should be possible to measure detailed neutrino signals out to very late times. We present the first comprehensive study of neutrino detection during the proto-neutron star cooling phase, considering a variety of outcomes, using all flavors, and employing detailed detector physics. For our nominal model, the event yields (at 10 kpc) after 10 s -- the approximate duration of the SN 1987A signal -- far exceed the entire SN 1987A yield, with $\simeq$250 ${\bar{\nu }}_e$ events (to 50 s) in Super-Kamiokande, $\simeq$110 ${\nu }_e$ events (to 40 s) in DUNE, and $\simeq$10 ${\nu }_{\mu },{\nu }_{\tau },{\bar{\nu }}_{\mu },{\bar{\nu }}_{\tau }$ events (to 20 s) in JUNO. These data would allow unprecedented probes of the proto-neutron star, including the onset of neutrino transparency and hence its transition to a neutron star. If a black hole forms, even at very late times, this can be clearly identified. But will the detectors fulfill their potential for this perhaps once-ever opportunity for an all-flavor, high-statistics detection of a core collapse? Maybe. Further work is urgently needed, especially for DUNE to thoroughly investigate and improve its MeV capabilities.

    ↳ astro-ph.HEhep-phnucl-thPRD(2021)·82 citations
20. 20*

    Probing the QCD phase structure using event-by-event fluctuations

    Tapan K. Nayak🇨🇭

    Heavy-ion collisions at relativistic energies probe matter at extreme conditions of temperatures and energy densities. The study of event-by-event fluctuations of experimental observables is crucial to probe the QCD phase transition, locate the critical point, and learn about the associated critical phenomena. At the critical point, all thermodynamic quantities behave anomalously. Fluctuation measurements provide access to thermodynamic response functions. We discuss the methods for obtaining the isothermal compressibility using particle multiplicity fluctuation, and specific heat using fluctuations in mean transverse momentum, temperature, and energy. Lattice QCD calculations have predicted non-monotonic behavior in the higher-order cumulants of conserved quantities at the critical point. Fluctuations in the multiplicity of charged to neutral particles have been measured to understand the formation of domains of disoriented chiral condensates. We review the recent fluctuation results as a function of collision centrality and energy from experiments at SPS, RHIC, and LHC. In addition, we propose to map the temperature fluctuations in eta-phi plane to probe local fluctuations of temperature and energy density.

    ↳ nucl-exhep-exhep-phnucl-thJ.Phys.Conf.Ser.(2020)·10 citations
21. 21*

    ${}^3$He Universe 2020

    G.E. Volovik🇫🇮

    The latest news from ${}^3$He Universe are presented together with the extended map of the Universe.

    ↳ cond-mat.othergr-qchep-phJ.Low Temp.Phys.(2021)·15 citations
22. 22*

    Comparison of the Lindhard-Sorensen and Mott-Bloch corrections to the Bethe stopping formula at moderately relativistic energies

    P.B. Kats🇧🇾 · K.V. Halenka🇧🇾 · O.O. Voskresenskaya🇷🇺

    The results of numerical calculating the total Mott-Bloch correction to the Bethe stopping formula and the Lindhard-Sorensen correction in the point nucleus approximation, as well as the Mott correction and the difference between the Lindhard-Sorensen and Bloch corrections, which were obtained by some rigorous and approximate methods, are compared for the ranges of a gamma factor of approximately from 1 to 10 and the ion nuclear charge number Z from 6 to 114. It is shown that the accurate calculation of the Mott-Bloch corrections based on the Mott exact cross section using a method previously proposed by one of the authors gives excellent agreement between its values and the values of the Lindhard-Sorensen corrections in the gamma and Z ranges under consideration. In addition, it is demonstrated that the results of stopping power calculations obtained by the two above-mentioned rigorous methods coincide with each other up to the seventh significant digit and provide the best agreement with experimental data in contrast with the results of some approximate methods, such as the methods of Ahlen, Jackson-McCarthy, etc.

    ↳ nucl-thhep-phPhys.Part.Nucl.Lett.(2021)·1 citation
23. 23*

    Decomposition of Feynman Integrals by Multivariate Intersection Numbers

    Hjalte Frellesvig🇮🇹 · Federico Gasparotto🇮🇹 · Stefano Laporta🇮🇹 · Manoj K. Mandal🇮🇹 · Pierpaolo Mastrolia🇮🇹 · Luca Mattiazzi🇮🇹 · Sebastian Mizera🇺🇸

    We present a detailed description of the recent idea for a direct decomposition of Feynman integrals onto a basis of master integrals by projections, as well as a direct derivation of the differential equations satisfied by the master integrals, employing multivariate intersection numbers. We discuss a recursive algorithm for the computation of multivariate intersection numbers and provide three different approaches for a direct decomposition of Feynman integrals, which we dub the straight decomposition, the bottom-up decomposition, and the top-down decomposition. These algorithms exploit the unitarity structure of Feynman integrals by computing intersection numbers supported on cuts, in various orders, thus showing the synthesis of the intersection-theory concepts with unitarity-based methods and integrand decomposition. We perform explicit computations to exemplify all of these approaches applied to Feynman integrals, paving a way towards potential applications to generic multi-loop integrals.

    ↳ hep-thhep-phJHEP(2021)·150 citations
24. 24*

    Tidal effects in quantum field theory

    Kays Haddad🇩🇰 · Andreas Helset🇩🇰

    We apply the Hilbert series to extend the gravitational action for a scalar field to a complete, non-redundant basis of higher-dimensional operators that is quadratic in the scalars and the Weyl tensor. Such an extension of the action fully describes tidal effects arising from operators involving two powers of the curvature. As an application of this new action, we compute all spinless tidal effects at the leading post-Minkowskian order. This computation is greatly simplified by appealing to the heavy limit, where only a severely constrained set of operators can contribute classically at the one-loop level. Finally, we use this amplitude to derive the $\mathcal{O}(G^2)$ tidal corrections to the Hamiltonian and the scattering angle.

    ↳ hep-thgr-qchep-phJHEP(2020)·102 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.