Mon·Jul 6, 2020Monday·July 6, 2020

1. 01*

   Shifted $\mu$-hybrid inflation, gravitino dark matter, and observable gravity waves

   George Lazarides🇬🇷 · Mansoor Ur Rehman🇵🇰 · Qaisar Shafi🇺🇸 · Fariha K. Vardag🇵🇰

   We investigate supersymmetric hybrid inflation in a realistic model based on the gauge symmetry $SU(4{)}_c\times SU(2{)}_L\times SU(2{)}_R$. The minimal supersymmetric standard model (MSSM) $\mu$ term arises, following Dvali, Lazarides, and Shafi, from the coupling of the MSSM electroweak doublets to a gauge singlet superfield which plays an essential role in inflation. The primordial monopoles are inflated away by arranging that the $SU(4{)}_c\times SU(2{)}_L\times SU(2{)}_R$ symmetry is broken along the inflationary trajectory. The interplay between the (above) $\mu$ coupling, the gravitino mass, and the reheating following inflation is discussed in detail. We explore regions of the parameter space that yield gravitino dark matter and observable gravity waves with the tensor-to-scalar ratio $r\sim 10^{-4}-10^{-3}$.

   hep-phastro-ph.COPRD(2021)·25 citations
2. 02*

   Texture zeros flavor neutrino mass matrix and triplet Higgs models

   Teruyuki Kitabayashi🇯🇵

   One- and two-zero textures for the flavor neutrino mass matrix have been successful in explaining mixing in the neutrino sector. Conservatively, six cases of one-zero textures and seven cases of two-zero textures are compatible with observations. We show that one case may be the most natural in the one- and two-zero textures schemes if tiny neutrino masses are generated by the type-II seesaw mechanism in triplet Higgs models.

   hep-phPRD(2020)·13 citations
3. 03*

   Singlet scalar dark matter in the non-commutative space-time: a viable hypothesis to explain the gamma-ray excess in the galactic center

   Zahra Rezaei🇮🇷 · S. Peyman Zakeri🇮🇷

   We explore the non-commutative space-time to revive the idea that gamma-ray excess in the galactic center can be the result of particle dark matter annihilation. In the non-commutative theory, the photon spectrum is produced by direct emission during this annihilation where a photon can be embed in the final state together with other direct products in new vertices. In the various configurations of dark matter phenomenology, we adopt the most common model known as singlet scalar. Calculating the relevant aspects of the model, we can obtain the photon flux in the galactic center. Comparing our numerical achievements with experimental data reveals that non-commutative space-time can be a reliable framework to explain the gamma-ray excess.

   hep-phInt.J.Mod.Phys.A(2023)·5 citations
4. 04*

   A Mixing Coupling Scheme for Spectra of Singly Heavy Baryons with Spin-1 Diquarks in P-waves

   Duojie Jia🇨🇳 · Ji-Hai Pan🇨🇳 · Cheng-Qun Pang🇨🇳

   A new scheme of state classification is proposed and applied to analyze masses of the heavy baryons ${\Omega }_Q$, ${\Sigma }_Q$ and ${\Xi }_Q^{\prime }$ in P-waves. The results confirm all excited ${\Omega }_c$ and ${\Omega }_b$ baryons reported recently by LHCb to be bound states of a P-wave $ss$-diquark and a respective charm or bottom quark, and thereby predict Regge trajectories for more excited ${\Omega }_c$ and ${\Omega }_b$ baryons. We suggest one excited {$J^P=5/2^{-}$} ${\Omega }_b$ state to be unseen by LHCb around $6352$ MeV, and predict P-wave masses of all spin-partners of the odd-parity baryons ${\Sigma }_c(2800)/{\Xi }_c^{\prime }(2942)$ and ${\Sigma }_b(6097)$/${\Xi }_b^{\prime }(6227)$. A computation is further given in a relativized potential quark models to explain matched values of spin couplings of all considered baryons, by which a scaling law for these spin couplings is discussed.

   hep-phEPJC(2021)·22 citations
5. 05*

   Towards muon-electron scattering at NNLO

   C.M. Carloni Calame🇮🇹 · M. Chiesa🇫🇷 · Syed Mehedi Hasan🇮🇹 · G. Montagna🇮🇹 · O. Nicrosini🇮🇹 · F. Piccinini🇮🇹

   The recently proposed MUonE experiment at CERN aims at providing a novel determination of the leading order hadronic contribution to the muon anomalous magnetic moment through the study of elastic muon-electron scattering at relatively small momentum transfer. The anticipated accuracy of the order of 10ppm demands for high-precision predictions, including all the relevant radiative corrections. The theoretical formulation for the fixed-order NNLO photonic radiative corrections is described and the impact of the numerical results obtained with the corresponding Monte Carlo code is discussed for typical event selections of the MUonE experiment. In particular, the gauge-invariant subsets of corrections due to electron radiation as well as to muon radiation are treated exactly. The two-loop contribution due to diagrams where at least two virtual photons connect the electron and muon lines is approximated taking inspiration from the classical Yennie-Frautschi-Suura approach. The calculation and its Monte Carlo implementation pave the way towards the realization of a simulation code incorporating the full set of NNLO corrections matched to multiple photon radiation, that will be ultimately needed for data analysis.

   hep-phhep-exJHEP(2020)·53 citations
6. 06*

   Color Glass Condensate at next-to-leading order meets HERA data

   G. Beuf🇵🇱 · H. Hänninen🇫🇮 · T. Lappi🇫🇮 · H. Mäntysaari🇫🇮

   We perform the first dipole picture fit to HERA inclusive cross section data using the full next-to-leading order (NLO) impact factor combined with an improved Balitsky-Kovchegov evolution including the dominant effects beyond leading logarithmic accuracy at low $x$. We find that three different formulations of the evolution equation that have been proposed in the recent literature result in a very similar description of HERA data, and robust predictions for future deep inelastic scattering experiments. We find evidence pointing towards a significant nonperturbative contribution to the structure function for light quarks, which stresses the need to extend the NLO impact factor calculation to massive quarks.

   hep-phnucl-thPRD(2020)·111 citations
7. 07*

   QED at NNLO with McMule

   P. Banerjee🇨🇭 · T. Engel🇨🇭 · A. Signer🇨🇭 · Y. Ulrich🇨🇭

   McMule is a framework for fully differential higher-order QED calculations of scattering and decay processes involving leptons. It keeps finite lepton masses, which regularises collinear singularities. Soft singularities are treated with dimensional regularisation and using FKS${}^{\ell }$ subtraction. We describe the implementation of the framework in Fortran 95, list the processes that are currently implemented, and give instructions on how to run the code. In addition, we present new phenomenological results for muon-electron scattering and lepton-proton scattering, including the dominant NNLO corrections. While the applications presented focus on MUonE, MUSE, and P2, the code can be used for a large number of planned and running experiments.

   hep-phSciPost Phys.(2020)·102 citations
8. 08*

   Constraints on electron-scattering interpretation of XENON1T excess

   So Chigusa🇯🇵 · Motoi Endo🇯🇵 · Kazunori Kohri🇯🇵

   Recently, the XENON1T experiment has observed an excess in the electronic recoil data in the recoil energy range of $1$-$7$ keV. One of the most favored new physics interpretations is electron scattering with a boosted particle with a velocity of $\sim 0.1$ and a mass of $\gtrsim 0.1\mathrm{MeV}$. If such a particle has a strong interaction with electrons, it may affect the standard scenario of cosmology or be observed at low-threshold direct detection experiments. We study various constraints, mainly focusing on those from the big-bang nucleosynthesis, supernova cooling, and direct detection experiments. We discuss the implication of these constraints on electron-scattering interpretation of the XENON1T excess.

   hep-phastro-ph.COJCAP(2020)·28 citations
9. 09*

   BSMPT v2 A Tool for the Electroweak Phase Transition and the Baryon Asymmetry of the Universe in Extended Higgs Sectors

   P. Basler🇩🇪 · M. Muhlleitner🇩🇪 · J. Müller🇩🇪

   We present the C++ code BSMPT v2 which is an extension of the previous code BSMPT for the calculation of the strength of the electroweak phase transition in extended Higgs sectors. The new version BSMPT v2 includes the features of BSMPT and extends the already implemented models (the 2-Higgs-Doublet model (2HDM) in its CP-conserving and CP-violating versions and the Next-to-2HDM) by the Complex Singlet Extension of the Standard Model (CxSM). The major upgrade is the implementation of the computation of the baryon asymmetry of the Universe (at present for the C2HDM) in two different approximation, called the FH and the VIA approach. Furthermore, the possibility of varying the renormalisation scale in the loop-corrected effective potential has been added. These changes and further smaller modifications are described in this manual. Additionally, a detailed explanation of the procedure for the implementation of new models is given, which has also changed with respect to the previous version.

   hep-phComput.Phys.Commun.(2021)·86 citations
10. 10*

    $\overline{\mathrm{MS}}$ renormalization of $S$-wave quarkonium wavefunctions at the origin

    Hee Sok Chung🇩🇪

    We compute $S$-wave quarkonium wavefunctions at the origin in the $\overline{\mathrm{MS}}$ scheme based on nonrelativistic effective field theories. We include the effects of nonperturbative long-distance behaviors of the potentials, while we determine the short-distance behaviors of the potentials in perturbative QCD. We obtain $\overline{\mathrm{MS}}$-renormalized quarkonium wavefunctions at the origin that have the correct scale dependences that are expected from perturbative QCD, so that the scale dependences cancel in physical quantities. Based on the calculation of the wavefunctions at the origin, we make model-independent predictions of decay constants and electromagnetic decay rates of $S$-wave charmonia and bottomonia, and compare them with measurements. We find that the poor convergence of perturbative QCD corrections are substantially improved when we include corrections to the wavefunctions at the origin in the calculation of decay constants and decay rates.

    hep-phJHEP(2020)·25 citations
11. 11*

    XENON1T signal from transition neutrino magnetic moments

    O. G. Miranda🇲🇽 · D. K. Papoulias🇬🇷 · M. Tórtola🇪🇸 · J. W. F. Valle🇪🇸

    The recent puzzling results of the XENON1T collaboration at few keV electronic recoils could be due to the scattering of solar neutrinos endowed with finite Majorana transition magnetic moments (TMMs). Within such general formalism, we find that the observed excess in the XENON1T data agrees well with this interpretation. The required TMM strengths lie within the limits set by current experiments, such as Borexino, specially when one takes into account a possible tritium contamination.

    hep-phPLB(2020)·57 citations
12. 12*

    Multi-charged TeV scale scalars and fermions in the framework of a radiative seesaw model

    Avnish🇮🇳 · Kirtiman Ghosh🇮🇳

    Explaining the tiny neutrino masses and non-zero mixings have been one of the key motivations for going beyond the framework of the Standard Model (SM). We discuss a collider testable model for generating neutrino masses and mixings via radiative seesaw mechanism. That the model does not require any additional symmetry to forbid tree-level seesaws makes its collider phenomenology interesting. The model includes multi-charged fermions/scalars at the TeV scale to realize the Weinberg operator at 1-loop level. After deriving the constraints on the model parameters resulting from the neutrino oscillation data as well as from the upper bound on the absolute neutrino mass scale, we discuss the production, decay and resulting collider signatures of these TeV scale fermions/scalars at the Large Hadron Collider (LHC). We consider both Drell-Yan and photoproduction. The bounds from the neutrino data indicate the possible presence of a long-lived multi-charged particle (MCP) in this model. We obtain bounds on these long-lived MCP masses from the ATLAS search for abnormally large ionization signature. When the TeV scale fermions/scalars undergo prompt decay, we focus on the 4-lepton final states and obtain bounds from different ATLAS 4-lepton searches. We also propose a 4-lepton event selection criteria designed to enhance the signal to background ratio in the context of this model.

    hep-ph6 citations
13. 13*

    Near-conformal dynamics in a chirally broken system

    Thomas Appelquist🇺🇸 · Richard C. Brower🇺🇸 · Kimmy K. Cushman🇺🇸 · George T. Fleming🇺🇸 · Andrew D. Gasbarro🇨🇭 · Anna Hasenfratz🇺🇸 · Xiao-Yong Jin🇺🇸 · Ethan T. Neil🇺🇸 · James C. Osborn🇺🇸 · Claudio Rebbi🇺🇸 · Enrico Rinaldi🇯🇵 · David Schaich🇬🇧 · Pavlos Vranas🇺🇸 · Oliver Witzel (Lattice Strong Dynamics Collaboration)🇺🇸

    Composite Higgs models must exhibit very different dynamics from quantum chromodynamics (QCD) regardless whether they describe the Higgs boson as a dilatonlike state or a pseudo-Nambu-Goldstone boson. Large separation of scales and large anomalous dimensions are frequently desired by phenomenological models. Mass-split systems are well-suited for composite Higgs models because they are governed by a conformal fixed point in the ultraviolet but are chirally broken in the infrared. In this work we use lattice field theory calculations with domain wall fermions to investigate a system with four light and six heavy flavors. We demonstrate how a nearby conformal fixed point affects the properties of the four light flavors that exhibit chiral symmetry breaking in the infrared. Specifically we describe hyperscaling of dimensionful physical quantities and determine the corresponding anomalous mass dimension. We obtain $y_m=1+{\gamma }^{\ast }=1.47(5)$ suggesting that $N_f=10$ lies inside the conformal window. Comparing the low energy spectrum to predictions of dilaton chiral perturbation theory, we observe excellent agreement which supports the expectation that the 4+6 mass-split system exhibits near-conformal dynamics with a relatively light $0^{++}$ isosinglet scalar.

    hep-phhep-latPRD(2021)·33 citations
14. 14*

    Variational Autoencoders for Anomalous Jet Tagging

    Taoli Cheng🇨🇦 · Jean-François Arguin🇨🇦 · Julien Leissner-Martin🇨🇦 · Jacinthe Pilette🇨🇦 · Tobias Golling🇨🇭

    We present a detailed study on Variational Autoencoders (VAEs) for anomalous jet tagging at the Large Hadron Collider. By taking in low-level jet constituents' information, and training with background QCD jets in an unsupervised manner, the VAE is able to encode important information for reconstructing jets, while learning an expressive posterior distribution in the latent space. When using the VAE as an anomaly detector, we present different approaches to detect anomalies: directly comparing in the input space or, instead, working in the latent space. In order to facilitate general search approaches such as bump-hunt, mass-decorrelated VAEs based on distance correlation regularization are also studied. We find that the naive mass-decorrelated VAEs fail at maintaining proper detection performance, by assigning higher probabilities to some anomalous samples. To build a performant mass-decorrelated anomalous jet tagger, we propose the Outlier Exposed VAE (OE-VAE), for which some outlier samples are introduced in the training process to guide the learned information. OE-VAEs are employed to achieve two goals at the same time: increasing sensitivity of outlier detection and decorrelating jet mass from the anomaly score. We succeed in reaching excellent results from both aspects. Code implementation of this work can be found at https://github.com/taolicheng/VAE-Jet

    hep-phhep-exstat.MLPRD(2023)·108 citations
15. 15*

    Constraints on Axion-Lepton coupling from Big Bang Nucleosynthesis

    Diptimoy Ghosh🇮🇳 · Divya Sachdeva🇮🇳

    In this article, we study the implications of the coupling between Axion-Like-Particles (ALPs) and Leptons to cosmology, in particular, the Big Bang Nucleosynthesis (BBN). We show that the BBN, through the constraint on the effective number of relativistic neutrino species, provides the most stringent bound on the ALP-electron interaction strength for the mass of axion between 20 keV and 1 MeV. For other values of the mass, the BBN bound complements the stellar-evolution and laboratory bounds.

    hep-phastro-ph.COJCAP(2020)·37 citations
16. 16*

    Searching for axion-like particles under strong gravitational lenses

    Aritra Basu🇩🇪 · Jishnu Goswami🇩🇪 · Dominik J. Schwarz🇩🇪 · Yuko Urakawa🇯🇵

    We establish strong gravitational lens systems as robust probes of axion-like particles (ALPs) -- a candidate for dark matter. A tiny interaction of photons with ALPs induces birefringence. Multiple images of gravitationally lensed polarised objects allow differential birefringence measurement, alleviating systematics and astrophysical dependencies. We apply this novel method to the lens system CLASS B1152+199 and constrain ALP-photon coupling $\le 9.2\times 10^{-11}{\mathrm{GeV}}^{-1}\text{ to }7.7\times 10^{-8}{\mathrm{GeV}}^{-1}$ ($95\%$ C.L.) for ALP mass between $3.6\times 10^{-21}\mathrm{eV}$ and $4.6\times 10^{-18}\mathrm{eV}$. A larger sample will improve the constraints.

    ↳ astro-ph.COhep-phPRL(2021)·28 citations
17. 17*

    Lattice QCD evaluation of the Compton amplitude employing the Feynman-Hellmann theorem

    K. U. Can🇦🇺 · A. Hannaford-Gunn🇦🇺 · R. Horsley🇬🇧 · Y. Nakamura🇯🇵 · H. Perlt🇩🇪 · P. E. L. Rakow🇬🇧 · G. Schierholz🇩🇪 · K. Y. Somfleth🇦🇺 · H. Stüben🇩🇪 · R. D. Young🇦🇺 · J. M. Zanotti🇦🇺

    The forward Compton amplitude describes the process of virtual photon scattering from a hadron and provides an essential ingredient for the understanding of hadron structure. As a physical amplitude, the Compton tensor naturally includes all target mass corrections and higher twist effects at a fixed virtuality, $Q^2$. By making use of the second-order Feynman-Hellmann theorem, the nucleon Compton tensor is calculated in lattice QCD at an unphysical quark mass across a range of photon momenta $3\lesssim Q^2\lesssim 7$ GeV${}^2$. This allows for the $Q^2$ dependence of the low moments of the nucleon structure functions to be studied in a lattice calculation for the first time. The results demonstrate that a systematic investigation of power corrections and the approach to parton asymptotics is now within reach.

    ↳ hep-lathep-phhep-thnucl-thPRD(2020)·57 citations
18. 18*

    A comparison of condensate mass of QCD vacuum between Wilson line approach and Schwinger effect

    Sara Tahery🇨🇳 · Liping Zou🇨🇳 · Xurong Chen🇨🇳

    By duality approach, we study condensate mass of QCD vacuum via dilaton wall background in presence of parameter $c$ which represents the gluon condensation in holographic set up. First from Wilson line calculation we find $m_0^2$ (condensate parameter in mixed nonlocal condensation) whose behavior mimics that of QCD. The value of $m_0^2$ that we find by this approach, is in agreement with QCD data. In the second step we consider produced mass m via Schwinger effect mechanism in presence of parameter $c$. We show that generally gluon condensation contribute mass dominantly and produced mass via Schwinger effect is suppressed by $m_0$ .

    ↳ hep-thhep-phCPC(2021)·3 citations
19. 19*

    Constraining the spin-independent elastic scattering cross section of dark matter using the Moon as a detection target and the background neutrino data

    Man Ho Chan🇨🇳 · Chak Man Lee🇨🇳

    Our Moon is a natural giant direct-detection target for constraining dark matter. By considering the dark matter capture rate of the Moon, we obtain some constraints of the spin-independent elastic scattering cross section of dark matter particles on nucleons ${\sigma }_p^{\mathrm{SI}}$ using the background neutrino data. The upper limits of ${\sigma }_p^{\mathrm{SI}}$ can be constrained to $\sim 10^{-38}-10^{-36}$ cm${}^2$ for certain `resonance dark matter mass' ranges. These stringent astrophysical constraints are complementary to the constraints obtained by the direct-detection experiments.

    ↳ astro-ph.HEhep-phPRD(2020)·15 citations
20. 20*

    Pion-mass dependence of the nucleon-nucleon interaction

    Qian-Qian Bai🇨🇳 · Chun-Xuan Wang🇨🇳 · Yang Xiao🇨🇳 · Li-Sheng Geng🇨🇳

    Nucleon-nucleon interactions, both bare and effective, play an important role in our understanding of the non-perturbative strong interaction, as well as nuclear structure and reactions. In recent years, tremendous efforts have been seen in the lattice QCD community to derive nucleon-nucleon interactions from first principles. Because of the daunting computing resources needed, most of such simulations were still performed with larger than physical light quark masses. In the present work, employing the recently proposed covariant chiral effective field theory (ChEFT), we study the light quark mass dependence of the nucleon-nucleon interaction extracted by the HALQCD group. It is shown that the pion-full version of the ChEFT can describe the lattice QCD data with $m_{\pi }=469$ MeV and their experimental counterpart reasonably well, while the pion-less version can describe the lattice QCD data with $m_{\pi }=672,837,1015,1171$ MeV, for both the ${}^1{S}_0$ and ${}^3{S}_1$-${}^3{D}_1$ channels. The slightly better description of the single channel than the triplet channel indicates that higher order studies are necessary for the latter. Our results confirmed previous studies that the nucleon-nucleon interaction becomes more attractive for both the singlet and triplet channels as the pion mass decreases towards its physical value. It is shown that the virtual bound state in the ${}^1{S}_0$ channel remains virtual down to the chiral limit, while the deuteron only appears for a pion mass smaller than about 400 MeV. It seems that proper chiral extrapolations of nucleon-nucleon interaction are possible for pion masses smaller than 500 MeV, similar to the mesonic and one-baryon sectors.

    ↳ nucl-thhep-lathep-phPLB(2020)·19 citations
21. 21*

    Cornering (quasi) degenerate neutrinos with cosmology

    Massimiliano Lattanzi🇮🇹 · Martina Gerbino🇮🇹 · Katherine Freese🇺🇸 · Gordon Kane🇺🇸 · José W. F. Valle🇪🇸

    In light of the improved sensitivities of cosmological observations, we examine the status of quasi-degenerate neutrino mass scenarios. Within the simplest extension of the standard cosmological model with massive neutrinos, we find that quasi-degenerate neutrinos are severely constrained by present cosmological data and neutrino oscillation experiments. % % We find that Planck 2018 observations of cosmic microwave background (CMB) anisotropies disfavour quasi-degenerate neutrino masses at $2.4$ Gaussian $\sigma$'s, while adding Baryon acoustic oscillations (BAO) data brings the rejection to 5.9$\sigma$'s. % The highest statistical significance with which one would be able to rule out quasi-degeneracy would arise if the sum of neutrino masses is $\Sigma m_{\nu }=60$ \meV (the minimum allowed by neutrino oscillation experiments); % indeed a sensitivity of 15 meV, as expected from a combination of future cosmological probes, would further improve the rejection level up to 17$\sigma$. % We discuss the robustness of these projections with respect to assumptions on the underlying cosmological model, and also compare them with bounds from $\beta$ decay endpoint and neutrinoless double beta decay studies.

    ↳ astro-ph.COhep-phJHEP(2020)·17 citations
22. 22*

    Radio-Frequency Searches for Dark Matter in Dwarf Galaxies

    Geoff Beck🇿🇦

    Dwarf spheroidal galaxies have long been discussed as optimal targets for indirect dark matter searches. However, the majority of such studies have been conducted with gamma-ray instruments. In this review, we discuss the very recent progress that has been made in radio-based indirect dark matter searches. We look at existing work on this topic and discuss the future prospects that motivate continued work in this newly developing field that promises to become, in the light of the up-coming Square Kilometre Array, a prominent component of the hunt for dark matter.

    ↳ astro-ph.HEastro-ph.COhep-phGalaxies(2019)·14 citations
23. 23*

    Distinguishing fuzzballs from black holes through their multipolar structure

    Massimo Bianchi🇮🇹 · Dario Consoli🇦🇹 · Alfredo Grillo🇮🇹 · Josè Francisco Morales🇮🇹 · Paolo Pani🇮🇹 · Guilherme Raposo🇮🇹

    Within General Relativity, the unique stationary solution of an isolated black hole is the Kerr spacetime, which has a peculiar multipolar structure depending only on its mass and spin. We develop a general method to extract the multipole moments of arbitrary stationary spacetimes and apply it to a large family of horizonless microstate geometries. The latter can break the axial and equatorial symmetry of the Kerr metric and have a much richer multipolar structure, which provides a portal to constrain fuzzball models phenomenologically. We find numerical evidence that all multipole moments are typically larger (in absolute value) than those of a Kerr black hole with the same mass and spin. Current measurements of the quadrupole moment of black-hole candidates could place only mild constraints on fuzzballs, while future gravitational-wave detections of extreme mass-ratio inspirals with the space mission LISA will improve these bounds by orders of magnitude.

    ↳ hep-thastro-ph.HEgr-qchep-phPRL(2020)·111 citations
24. 24*

    On coalescence as the origin of nuclei in hadronic collisions

    Francesca Bellini🇨🇭 · Kfir Blum🇮🇱 · Alexander Phillip Kalweit🇨🇭 · Maximiliano Puccio🇨🇭

    The origin of weakly-bound nuclear clusters in hadronic collisions is a key question to be addressed by heavy-ion collision (HIC) experiments. The measured yields of clusters are approximately consistent with expectations from phenomenological statistical hadronisation models (SHMs), but a theoretical understanding of the dynamics of cluster formation prior to kinetic freeze out is lacking. The competing model is nuclear coalescence, which attributes cluster formation to the effect of final state interactions (FSI) during the propagation of the nuclei from kinetic freeze out to the observer. This phenomenon is closely related to the effect of FSI in imprinting femtoscopic correlations between continuum pairs of particles at small relative momentum difference. We give a concise theoretical derivation of the coalescence--correlation relation, predicting nuclear cluster spectra from femtoscopic measurements. We review the fact that coalescence derives from a relativistic Bethe-Salpeter equation, and recall how effective quantum mechanics controls the dynamics of cluster particles that are nonrelativistic in the cluster centre of mass frame. We demonstrate that the coalescence--correlation relation is roughly consistent with the observed cluster spectra in systems ranging from PbPb to pPb and pp collisions. Paying special attention to nuclear wave functions, we derive the coalescence prediction for hypertriton and show that it, too, is roughly consistent with the data. Our work motivates a combined experimental programme addressing femtoscopy and cluster production under a unified framework. Upcoming pp, pPb and peripheral PbPb data analysed within such a programme could stringently test coalescence as the origin of clusters.

    ↳ nucl-thhep-exhep-phPRC(2021)·69 citations
25. 25*

    Extraction of baryonia from the lightest anti-protonic atoms

    B. Loiseau🇫🇷 · S. Wycech🇵🇱

    Anti-protonic hydrogen and helium atoms are analyzed. Level shifts and width are expressed in terms of $\bar{p}$-nucleon sub-threshold scattering lengths and volumes. Experimental data are compared to results obtained from the 2009 version of the Paris $N\bar{N}$ interaction potential. Comparison with 1999 version is also made. Effects of $N\bar{N}$ quasi-bound states are discussed. Atomic 2P hyperfine structure is calculated for antiprotonic deuterium and the significance of new measurements is indicated.

    ↳ nucl-thhep-phnucl-exPRC(2020)·8 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.