Tue·Aug 23, 2022Tuesday·August 23, 2022

1. 01*

   Electromagnetic probes of the Quark-Gluon Plasma

   Gojko Vujanovic🇺🇸

   The penetrating nature of electromagnetic probes makes them an ideal candidate to study properties of the Quark-Gluon Plasma (QGP). A selection of recent developments in the theory and phenomenology of electromagnetic probes is discussed, with an emphasis given towards how these probes can be used to constrain QGP trapnsport coefficients. A Bayesian treatment of electromagnetic radiation, similar to the one of soft hadronic observables and jets, is suggested as a path towards imposing more stringent constraints on various transport coefficients of the QCD medium.

   hep-phnucl-exnucl-thActa Phys.Polon.Supp.(2023)·2 citations
2. 02*

   Predicting the Masses of Exotic Hadrons with Data Augmentation Using Multilayer Perceptron

   Huseyin Bahtiyar🇹🇷

   Recently, there have been significant developments in neural networks, which led to the frequent use of neural networks in the physics literature. This work is focused on predicting the masses of exotic hadrons, doubly charmed and bottomed baryons using neural networks trained on meson and baryon masses that are determined by experiments. The original data set has been extended using the recently proposed artificial data augmentation methods. We have observed that the neural network's predictive ability increases with the use of augmented data. The results indicated that data augmentation techniques play an essential role in improving neural network predictions; moreover, neural networks can make reasonable predictions for exotic hadrons, doubly charmed, and doubly bottomed baryons. The results are also comparable to Gaussian Process and Constituent Quark Model.

   hep-phcs.LGhep-latInt.J.Mod.Phys.A(2023)·4 citations
3. 03*

   Primordial black holes and mirror dark matter

   Teruyuki Kitabayashi🇯🇵

   If mirror matter exists but cannot comprise all of the dark matter (DM) in the universe, we can expect that the additional DM component may only interact with the other sectors gravitationally. One of the natural candidate of a gravitationally interacting component is a primordial black hole (PBH). Therefore, if mirror matter exists but cannot comprise all of the DM in the universe, the existence of PBH may be expected as a candidate of the additional DM component. In this case, the remaining DM components may be PBHs or $SU(3)\times SU(2)\times U(1)$ singlet particles from PBH. We show constraints on PBH with the mirror DM. Particularly, the initial PBH mass is estimated to be $10^{17}\mathrm{g}\lesssim M_{\mathrm{PBH}}\lesssim 10^{23}\mathrm{g}$, if the DM comprises mirror baryons and PBHs.

   hep-phastro-ph.COInt.J.Mod.Phys.A(2022)·9 citations
4. 04*

   Extra dimensions with light and heavy neutral leptons: An application to CE$\nu$NS

   Amir N. Khan🇩🇪

   We explore the possibility of relating extra dimensions with light and heavy Dirac-type neutral leptons and develop a framework for testing them in various laboratory experiments. The Kaluza-Klein modes in the large extra dimension models of the light neutral leptons could mix with the standard model neutrinos and produce observable effects in the oscillation experiments. We show that the chirality flipping up-scattering processes occurring through either neutrino magnetic dipole moment or the weakly coupled scalar interactions can also produce heavy Kaluza-Klein modes of the corresponding right-handed neutral leptons propagating in one or more extra dimensions. However, to conserve the four-dimensional energy-momentum, their masses must be below the maximum energy of the neutrinos in the initial state. The appreciable size of extra dimensions connected with these heavy neutral leptons can thus affect the cross-sections of these processes. This framework applies to any up-scattering process. Our work here focuses only on its application to the coherent elastic neutrino-nucleus scattering process. We derive constraints on the size of extra dimensions using the COHERENT data in oscillation and up-scattering processes. For model with one large extra dimension for the light neutral leptons, we obtain the limits, $R\sim 3\mu$m (NH) and $R\sim 2.5\mu$m (IH), on the size of extra dimension corresponding to the absolute mass limit, $m_0\le 3\times 10^{-3}$ eV at 90$\%$ C.L. from the short-baseline oscillations. Using the up-scattering process for heavy neutral leptons, we obtain new parameter spaces between the size of extra dimensions and parameters of the dipole or scalar interactions.

   hep-phhep-exJHEP(2023)·12 citations
5. 05*

   The electromagnetic decays of $X(3823)$ as the ${\psi }_2(1^3{D}_2)$ state and its radial excited states

   Wei Li🇨🇳 · Su-Yan Pei🇨🇳 · Tianhong Wang🇨🇳 · Ying-Long Wang🇨🇳 · Tai-Fu Feng🇨🇳 · Guo-Li Wang🇨🇳

   We study the electromagnetic (EM) decays of $X(3823)$ as the ${\psi }_2(1^3{D}_2)$ state by using the relativistic Bethe-Salpeter method. Our results are $\Gamma [X(3823)\to {\chi }_{{}_{c0}}\gamma ]=1.2$ keV, $\Gamma [X(3823)\to {\chi }_{{}_{c1}}\gamma ]=265$ keV, $\Gamma [X(3823)\to {\chi }_{{}_{c2}}\gamma ]=57$ keV and $\Gamma [X(3823)\to {\eta }_{{}_c}\gamma ]=1.3$ keV. The ratio $\mathcal{B}[X(3823)\to {\chi }_{{}_{c2}}\gamma ]/\mathcal{B}[X(3823)\to {\chi }_{{}_{c1}}\gamma ]=0.22$, agrees with the experimental data. Similarly, the EM decay widths of ${\psi }_{{}_2}(n^3{D}_{{}_2})$, $n=2,3$, are predicted, and we find the dominant decays channels are ${\psi }_{{}_2}(n^3{D}_{{}_2})\to {\chi }_{{}_{c1}}(nP)\gamma$, where $n=1,2,3$. The wave function include different partial waves, which means the relativistic effects are considered. We also study the contributions of different partial waves.

   hep-phhep-exPRD(2023)·12 citations
6. 06*

   Tree-level new physics in $R(K^{(\ast )})$

   Jong-Phil Lee🇰🇷

   We implement the ${\chi }^2$ fit for $R(K^{(\ast )})$ with possible tree-level new physics in a model-independent parametrization. Relevant Wilson coefficients are decomposed into the new physics scale, its power, and the fermionic couplings. Constraints from the branching ratio of $B_s\to {\mu }^{+}{\mu }^{-}$ can be naturally incorporated with the scheme. For a reasonable set of the parameter ranges it is found that the new physics is less than $\sim 5\mathrm{TeV}$. Some new physics models including the leptoquark, $Z^{\prime }$, etc. can be embraced within our framework. We give comments on new LHCb data which are close to the standard model predictions.

   hep-phMod.Phys.Lett.A(2023)·2 citations
7. 07*

   Zoom in muon survival probability with sterile neutrino for CP and T-violation

   Kiran Sharma🇮🇳 · Sudhanwa Patra (IIT Bhilai)🇮🇳

   We present the approximated analytic expressions for the muon survival probability in a $3+1$ mixing scenario in the presence of matter effect using the S-matrix formalism. We find that all the individual terms contributing to the muon survival probability can significantly reduce to just three contributions. The leading order contribution comes from the three flavor muon survival probability followed by the two sub-leading contributions arising from active-sterile mixing. Furthermore, to more simplify the results we adopt the well known series expansion relations about mass-hierarchy parameter $\alpha =\Delta m_{21}^2/\Delta m_{31}^2$ and the mixing angle $\sin {\theta }_{13}$ in the vanishing limit of ${\alpha }^2$. We discuss the relevance of muon survival probability to probe the CP and T-violation studies coming from the new physics. We also compare the analytic relation between vacuum and matter contributions to the muon survival probability at the leading order. Finally, we comment on the probability behavior at the various long baselines relevant to understand the atmospheric-neutrino sector and to resolve the existing mass-hierarchy problem.

   hep-ph1 citation
8. 08*

   Fireball baryogenesis from early structure formation due to Yukawa forces

   Marcos M. Flores🇺🇸 · Alexander Kusenko🇺🇸 · Lauren Pearce🇺🇸 · Graham White🇯🇵

   We show that viable electroweak baryogenesis can be realized without a first-order phase transition if plasma is heated inhomogeneously by nongravitational structure formation in some particle species. Yukawa interactions can mediate relatively long-range attractive forces in the early Universe. This creates an instability and leads to growth of structure in some species even during the radiation dominated era. At temperatures below the electroweak scale, the collapsing and annihilating halos can heat up plasma in fireballs that expand and create the out-of-equilibrium high-temperature environment suitable for generating the baryon asymmetry. The plasma temperature at the time of baryogenesis can be as low as a few MeV, making it consistent with both standard and low-reheat cosmologies.

   hep-phastro-ph.COPRD(2023)·18 citations
9. 09*

   A Lagrangian with $E_8\times E_8$ symmetry for the standard model and pre-gravitation I. -- The bosonic Lagrangian, and a theoretical derivation of the weak mixing angle

   Sherry Raj🇮🇳 · Tejinder P. Singh🇮🇳

   Building on earlier work, we propose an elementary Lagrangian for the unification of the standard model with pre-gravitation, assumed to have an unbroken $E_8\times E_8$ symmetry. The Lagrangian is patterned after the kinetic energy of a free particle in Newtonian dynamics, generalising it to the matrix-valued Lagrangian dynamics of a 2-brane on a split bioctonionic space. Symmetry breaking gives rise to the standard model quarks and leptons of three generations along with the known gauge interactions, and a novel right-handed counterpart $SU(3{)}_{grav}\times SU(2{)}_R\times U(1{)}_g$ identified as pre-gravitation. The goal of the present series of papers is to investigate if this pre-quantum, pre-spacetime matrix-valued Lagrangian dynamics can lead to the emergence of quantum field theory for the standard model, and classical general relativity, possibly with some additional corrections. In this paper we work out the bosonic part of the Lagrangian, and show how the anticipated 32 gauge bosons are recovered from the elementary Lagrangian. As an application, we show that the asymptotic low energy weak mixing angle ${\theta }_W$ is given by a solution of the equation $1=(1/2)\sqrt{\cos ({\theta }_W/2)}+\sqrt{\sin ({\theta }_W/2)}$, yielding ${\sin }^2{\theta }_W\approx 0.24996$.

   hep-phhep-th16 citations
10. 10*

    Open Charm mesons in magnetized nuclear matter -- effects of (inverse) magnetic catalysis

    Sourodeep De · Amruta Mishra

    The in-medium masses of the open charm ($D$ and $\bar{D}$) mesons in magnetized isospin asymmetric nuclear matter are investigated within a chiral effective model, including the contributions of the Dirac sea (DS) to the self-energies of the nucleons. Within the model, the masses of these mesons are calculated from their interactions with the nucleons and the scalar ($\sigma \sim (⟨\bar{u}u⟩+⟨\bar{d}d⟩)$, $\zeta \sim ⟨\bar{s}s⟩$ and $\delta \sim (⟨\bar{u}u⟩-⟨\bar{d}d⟩)$) fields. The Dirac sea contributions are observed to lead to an enhancement (reduction) of the quark condensates with increase in magnetic field, an effect called `(inverse) magnetic catalysis'. These contributions are observed to appreciably modify the open charm meson masses calculated within the chiral effective model. In the presence of an external magnetic field, there is mixing of the pseudoscalar and the vector mesons (PV mixing), leading to as a drop (increase) in the mass of the pseudoscalar (longitudinal component of the vector) meson. The effects of the (inverse) magnetic catalysis, in addition to the PV mixing and Landau level contribtuions (for charged mesons) are observed to lead to significant modifications to the masses of the open charm mesons. These can modify the decay widths of the charmonium states to open charm mesons, e.g., $\psi (3770)\to D\bar{D}$, as well as $D^{\ast }\to D\pi$ (and $\overline{D^{\ast }}\to \bar{D}\pi$), which can affect the production of the open charm and charmonium states in ultra relativistic peripheral heavy ion collision experiments, where the created magnetic field is huge.

    hep-phnucl-thPRC(2023)·18 citations
11. 11*

    Corrections to the Gyromagnetic Factor in Very Special Relativity

    Benjamin Koch🇦🇹 · Enrique Muñoz🇨🇱 · Alessandro Santoni🇨🇱

    We consider Very Special Relativity corrections to the energy spectrum of a $C-$invariant Dirac Fermion in a static and homogeneous magnetic field $\vec{B}$. First, in the case of $\vec{B}$ parallel to the spatial VSR preferred direction $\vec{n}$, finding that the expression for the energy spectrum stays the same, except for a correction to the mass arising from the VSR contribution. Then, we relax the parallelism condition, finding a new equation for the energy spectrum. We solve this equation perturbatively. With a Penning trap's experiment in mind, we derive the first order VSR corrections to the electron's $g-2$ factor. Finally, using the current errors on the electron's $g$-factor measurements in Penning trap's experiments, we obtain an upper bound to the VSR electron mass parameter, and therefore also to the VSR electronic neutrino mass, of $0.824eV$. This result does not contradict the possibility for VSR to be the origin of neutrino masses.

    hep-phhep-thPRD(2022)·4 citations
12. 12*

    Importance of higher harmonics and $v_4$ puzzle in quark-gluon plasma tomography

    Dusan Zigic🇷🇸 · Jussi Auvinen🇷🇸 · Igor Salom🇷🇸 · Pasi Huovinen🇷🇸 · Magdalena Djordjevic🇷🇸

    QGP tomography aims to constrain the parameters characterizing the properties and evolution of Quark-Gluon Plasma (QGP) formed in heavy-ion collisions, by exploiting low and high-$p_{\perp }$ theory and data. Higher-order harmonics $v_n$ ($n>2$) are an important -- but seldom explored -- part of this approach. However, to take full advantage of them, several issues have to be addressed: i) consistency of different methods for calculating $v_n$, ii) importance of event-by-event fluctuations to high-$p_{\perp }$ $R_{AA}$ and $v_2$ predictions, iii) sensitivity of higher harmonics to the initial state of fluid-dynamical evolution. We obtain that i) several methods for calculating harmonics are compatible with each other, ii) event-by-event calculations are important in mid-central collisions, and iii) various initializations of the evolution of the medium lead to quantitatively and qualitatively different predictions, likely to be distinguished by future measurements. We also find that the present high-$p_{\perp }$ $v_4$ data cannot be reproduced using initial states for fluid-dynamical evolution given by state-of-the-art models. We call this discrepancy high-$p_{\perp }$ $v_4$ puzzle at the LHC.

    hep-phPRC(2022)·10 citations
13. 13*

    Semileptonic baryonic $B$ decays

    Yu-Kuo Hsiao🇨🇳

    We study the semileptonic $B\to \mathbf{B}{\bar{\mathbf{B}}}^{\prime }L{\bar{L}}^{\prime }$ decays with $\mathbf{B}{\bar{\mathbf{B}}}^{\prime }$ ($L{\bar{L}}^{\prime }$) representing a baryon (lepton) pair. Using the new determination of the $B\to \mathbf{B}{\bar{\mathbf{B}}}^{\prime }$ transition form factors, we obtain $\mathcal{B}(B^{-}\to p\bar{p}{\mu }^{-}{\bar{\nu }}_{\mu })=(5.4\pm 2.0)\times 10^{-6}$ agreeing with the current data. Besides, $\mathcal{B}(B^{-}\to \Lambda \bar{p}\nu \bar{\nu })=(3.5\pm 1.0)\times 10^{-8}$ is calculated to be 20 times smaller than the previous prediction. In particular, we predict $\mathcal{B}({\bar{B}}_s^0\to p\bar{\Lambda }{e}^{-}{\bar{\nu }}_e,p\bar{\Lambda }{\mu }^{-}{\bar{\nu }}_{\mu },p\bar{\Lambda }{\tau }^{-}{\bar{\nu }}_{\tau })=(2.1\pm 0.6,2.1\pm 0.6,1.7\pm 1.0)\times 10^{-6}$ and $\mathcal{B}({\bar{B}}_s^0\to \Lambda \bar{\Lambda }\nu \bar{\nu })=(0.8\pm 0.2)\times 10^{-8}$, which can be accessible to the LHCb experiment.

    hep-phhep-exEPJC(2023)·7 citations
14. 14*

    On the question of quark confinement in the Abelian U(1) QED gauge interaction

    Cheuk-Yin Wong🇺🇸

    If we approximate light quarks as massless and apply the Schwinger confinement mechanism to light quarks, we will reach the conclusion that a light quark $q$ and its antiquark $\bar{q}$ will be confined as a $q\bar{q}$ boson in the Abelian U(1) QED gauge interaction in (1+1)D, as in an open string. From the work of Coleman, Jackiw, and Susskind, we can infer further that the Schwinger confinement mechanism persists even for massive quarks in (1+1)D. Could such a QED-confined $q\bar{q}$ one-dimensional open string in (1+1)D be the idealization of a flux tube in the physical world in (3+1)D, similar to the case of QCD-confined $q\bar{q}$ open string? If so, the QED-confined $q\bar{q}$ bosons may show up as neutral QED mesons in the mass region of many tens of MeV (PRC81(2010)064903 & JHEP2020(8)165). Is it ever possible that a quark and an antiquark be produced and interact in QED alone to form a confined QED meson? Is there any experimental evidence for the existence of a QED meson (or QED mesons)? The observations of the anomalous soft photons, the X17 particle, and the E38 particle suggest that they may bear the experimental evidence for the existence of such QED mesons. Further confirmation and investigations on the X17 and E38 particles will shed definitive light on the question of quark confinement in QED in (3+1)D. Implications of quark confinement in the QED interaction are discussed.

    hep-phhep-thnucl-thFront.Phys.(Beijing)(2023)·5 citations
15. 15*

    Gravitational Waves-Tomography of Low-Scale-Leptogenesis

    Satyabrata Datta🇮🇳 · Rome Samanta🇨🇿

    A long-lived scalar field ($\Phi$) which couples weakly to the right-handed (RH) neutrinos ($N_{Ri}$), generates small RH neutrino masses ($M_i$) in Low-Scale-Leptogenesis (LSL) mechanisms, despite having a large vacuum expectation value $v_{\Phi }$. In this case, the correlation shared by the $M_i$s and the duration of the non-standard cosmic history driven by the $\Phi$ provides an excellent opportunity to study LSL signatures on primordial gravitational waves (GWs). We find it engaging, specifically for the gravitational waves that originate due to the inflationary blue-tilted tensor power spectrum and propagate through the non-standard cosmic epoch. Depending on $M_i$, broadly, the scenario has two significant consequences. First, if LSL is at play, GWs with a sizeable blue tilt do not contradict the Big-Bang-Nucleosynthesis (BBN) bound even for the post-inflationary models with very high-scale reheating. Second, it opens up a possibility to probe LSLs via a low-frequency and a complementary high-frequency measurement of GW-spectral shapes which are typically double-peaked. For a case study, we consider the recent results on GWs from the Pulsar-Timing-Arrays (PTAs) as a `measurement' at the low frequencies and forecast the signatures of LSL mechanisms at the higher frequencies.

    hep-phastro-ph.COJHEP(2022)·29 citations
16. 16*

    Discovering neutrinoless double-beta decay in the era of precision neutrino cosmology

    Manuel Ettengruber🇩🇪 · Matteo Agostini🇬🇧 · Allen Caldwell🇩🇪 · Philipp Eller🇩🇪 · Oliver Schulz🇩🇪

    We evaluate the discovery probability of a combined analysis of proposed neutrinoless double-beta decay experiments in a scenario with normal ordered neutrino masses. The discovery probability strongly depends on the value of the lightest neutrino mass, ranging from zero in case of vanishing masses and up to 80-90\% for values just below the current constraints. We study the discovery probability in different scenarios, focusing on the exciting prospect in which cosmological surveys will measure the sum of neutrino masses. Uncertainties in nuclear matrix element calculations partially compensate each other when data from different isotopes are available. Although a discovery is not granted, the theoretical motivations for these searches and the presence of scenarios with high discovery probability strongly motivates the proposed international, multi-isotope experimental program.

    hep-phhep-exPRD(2022)·9 citations
17. 17*

    $1/(M_R{)}_{33}$ expansion of the type-I seesaw mechanism and partial $Z_2$ symmetry for TM${}_{1,2}$ mixing

    Masaki J. S. Yang🇯🇵

    We consider an expansion of the type-I seesaw mechanism by the inverse of the 3-3 matrix element $1/(M_R{)}_{33}$ of the mass matrix of right-handed neutrinos $M_R$. Conditions of such a situation are obtained for $M_R$ and the Dirac mass matrix $m_D$. In this case, a partial $Z_2$ symmetry such as $S{m}_D{P}_{}=\pm m_D{P}_{}$ with a projection matrix $P_{}=\mathrm{diag}(1,1,0)$ leads to an approximate $Z_2$ symmetry by $S$ for the neutrino mass matrix $m_{\nu }$. Such a partial $Z_2$ symmetry is desirable in the context of unified theories because it allows hierarchical $m_D$ and the large mixing of $m_{\nu }$ simultaneously.

    hep-ph1 citation
18. 18*

    Open bottom mesons in magnetized matter -- effects of (inverse) magnetic catalysis

    Sourodeep De🇮🇳 · Pallabi Parui🇮🇳 · Amruta Mishra🇮🇳

    In-medium masses of the pseudoscalar and vector open bottom mesons ($B$, $\bar{B}$, $B_s$ and $B^{\ast }$, ${\bar{B}}^{\ast }$, $B_s^{\ast }$) are studied in the magnetized nuclear matter by considering the effects of Dirac sea, within the chiral effective model. The mass modifications arise due to the interactions of the open bottom mesons with the nucleons and the scalar mesons, calculated in terms of the scalar and number densities of the nucleons and the scalar fields fluctuations. The effects of the magnetized Dirac sea lead to the considerable changes in the scalar fields with magnetic field, which are related to the light quark condensates. There is observed to be a (reduction) enhancement in the light quark condensates with magnetic field, a phenomenon called (inverse) magnetic catalysis.The contribution of the magnetic field on the Fermi sea of nucleons are taken into account through the Landau energy levels of protons and anomalous magnetic moments (AMMs) of the nucleons. The additional contribution of the lowest Landau level for the charged mesons are considered. The spin-magnetic field interaction between the longitudinal component of the vector and the pseudoscalar mesons ($B^{\ast ||}({\bar{B}}^{\ast ||})-B(\bar{B}))$ and ($B_s^{\ast ||}-B_s$) are studied, which lead to a level repulsion between their masses with magnetic field. Magnetic fields are observed to have significant contribution on the in-medium masses of the open bottom mesons through the Dirac sea effect as comparedto the case when this effect is not considered. In vacuum, considerable changes are obtained only due to the magnetized Dirac sea at zero and finite nucleonic AMMs.

    hep-phIJMPE(2022)·10 citations
19. 19*

    Learning to Identify Semi-Visible Jets

    Taylor Faucett🇺🇸 · Shih-Chieh Hsu🇺🇸 · Daniel Whiteson🇺🇸

    We train a network to identify jets with fractional dark decay (semi-visible jets) using the pattern of their low-level jet constituents, and explore the nature of the information used by the network by mapping it to a space of jet substructure observables. Semi-visible jets arise from dark matter particles which decay into a mixture of dark sector (invisible) and Standard Model (visible) particles. Such objects are challenging to identify due to the complex nature of jets and the alignment of the momentum imbalance from the dark particles with the jet axis, but such jets do not yet benefit from the construction of dedicated theoretically-motivated jet substructure observables. A deep network operating on jet constituents is used as a probe of the available information and indicates that classification power not captured by current high-level observables arises primarily from low-$p_{\text{T}}$ jet constituents.

    hep-phJHEP(2022)·18 citations
20. 20*

    Subcritical regime of hybrid inflation with modular $A_4$ symmetry

    Yoshihiro Gunji🇯🇵 · Koji Ishiwata🇯🇵 · Takahiro Yoshida🇯🇵

    We consider a supergravity model that has the modular $A_4$ symmetry and discuss the interplay between the neutrino mixing and inflation. The model contains right-handed neutrinos that have the Majorana masses and additional Yukawa couplings to the waterfall field. In the model an active neutrino is massless and we find that only the inverted hierarchy is allowed and the Majorana phase is predicted to be around $\pm (120\text{–}180{)}^{\circ }$ from the observed neutrino mixing data. In the early universe, one of right-handed sneutrinos plays the role of the inflaton field. Focusing on the subcritical regime of the hybrid inflation that is consistent with the cosmic microwave background data, we analyze the dynamics of the scalar sector and derive an upper bound $\mathcal{O}(10^{10})\mathrm{GeV}$ on the scale of the Majorana mass.

    hep-phastro-ph.COJHEP(2022)·20 citations
21. 21*

    The strong decays of the low-lying $\rho$-mode $1P$-wave singly heavy baryons

    Wen-Jia Wang🇨🇳 · Li-Ye Xiao🇨🇳 · Xian-Hui Zhong🇨🇳

    We have systematically calculated the strong decays of the low-lying $\rho$-mode $1P$-wave ${\Lambda }_{c(b)}$, ${\Sigma }_{c(b)}$, ${\Xi }_{c(b)}$, ${\Xi }_{c(b)}^{{}^{\prime }}$, ${\Omega }_{c(b)}$ baryons using the chiral quark model within the $j$-$j$ coupling scheme. For the controversial states, our results indicate: (i) For the singly charmed heavy baryons, the newly observed ${\Lambda }_c(2910{)}^{+}$ is a good candidate of the $J^P=5/2^{-}$ state ${\Lambda }_c|J^P={\frac{5}{2}}^{-},2{⟩}_{\rho }$. (ii) For the singly bottom heavy baryons, the ${\Xi }_b(6227{)}^{-}$ favors the $J^P=5/2^{-}$ state ${\Xi }_b|J^P={\frac{5}{2}}^{-},2{⟩}_{\rho }$. (iii) The other missing $\rho$-mode $1P$-wave excitations in ${\Lambda }_b$, ${\Sigma }_{c(b)}$ and ${\Xi }_{c(b)}^{{}^{\prime }}$ families appear to be broad structures with $\Gamma$$\sim$(100-200) MeV, and their strong decay widths are sensitive to their masses. (iv) The $\rho$-mode $1P$-wave ${\Xi }_{c(b)}$ and ${\Omega }_{c(b)}$ baryons have a relatively narrow decay width of a few MeV or a few tens of MeV, and have a good potential to be observed in forthcoming experiments.

    hep-phPRD(2022)·15 citations
22. 22*

    $Z$ boson radiative decays to a $P$-wave quarkonium at NNLO and LL accuracy

    Wen-Long Sang (SWU)🇨🇳 · De-Shan Yang (UCAS)🇨🇳 · Yu-Dong Zhang (SWU)🇨🇳

    In this work, we study the radiative decay of $Z$ boson to a $P$-wave quarkonium $H$ in association with a photon, where $H$ can be ${\chi }_{QJ}$, $h_Q$ with $Q=c,b$ and $J=0,1,2$. The helicity amplitudes and the unpolarized decay widths are evaluated up to QCD next-to-next-to-leading order (NNLO) within the framework of nonrelativistic QCD (NRQCD). For the first time, we check the NRQCD factorization for $h_Q$ exclusive production at two-loop order. The leading logarithms (LL) of $m_Z^2/m_Q^2$ in the leading-twist short-distance coefficients, which may potentially ruin the perturbative convergence, are resummed to all orders of ${\alpha }_s$ by employing the light-cone factorization. We find the radiative corrections are considerable for ${\chi }_{Q2}$ and $h_Q$ productions, while are moderate or even minor for other channels. We also notice that the LL resummation can change the leading-order predictions for decay widths by more than 25\% for ${\chi }_{c0,2}$ and $h_c$ productions, and by around 50\% for ${\chi }_{c1}$ production. However, effects of the LL resummation on the next-to-leading-order and NNLO predictions are notably mitigated. Some phenomenological explorations are also performed.

    hep-phPRD(2022)·13 citations
23. 23*

    Search for Mono-Higgs Signals in $b\bar{b}$ Final States Using Deep Neural Networks

    A. Hammad🇰🇷 · S. Khalil🇪🇬 · S. Moretti🇬🇧

    We study mono-Higgs signatures emerging in an illustrative new physics scenario involving Standard Model Higgs boson decays to bottom quark pairs using Hybrid Deep Neural Networks. We use a Multi-Layer Perceptron to analyze the kinematic observables and optimize the signal-to-background discrimination. The global color flow structure of hard jets emerging from the decay of heavy particles with different color charges is crucial to single out the mono-Higgs signature. Upon embedding the different color flow structures for signal and backgrounds into constructed images, we use a Convolution Neural Network to analyze the latter. Specifically, the approach takes initially a mono-type data as input, frittering away invaluable multi-source and multi-scale information. We then discuss a general architecture of Hybrid Deep Neural Networks that supports instead mixed input data. In comparison with single input Deep Neural Networks, like MultiLayers Perceptron or Convolution Neural Network, the Hybrid Deep Neural Networks provide higher capacity in feature extraction and thus in signal vs background classification performance. We provide reference results for the case of the High-Luminosity Large Hadron Collider.

    hep-phPRD(2023)·10 citations
24. 24*

    Twist-2 light-quark distribution functions in a singly heavy baryon in the large $N_c$ limit

    Hyeon-Dong Son🇰🇷 · Hyun-Chul Kim🇰🇷

    A singly heavy baryon can be considered as a state consisting of the $N_c-1$ light valence quarks that create the pion mean field in the large $N_c$ limit. In the limit of the infinitely heavy quark mass, a heavy quark inside a singly heavy baryon is regarded as a mere static color source. It is required only to make the singly heavy baryon a color singlet. Thus, the $N_c-1$ valence quarks govern quark dynamics inside the singly heavy baryon. Within this pion mean field framework, we investigate the twist-2 unpolarized and longitudinally polarized light-quark distribution functions inside charmed and bottom baryons at a low renormalization point. We observe that the light quarks inside a heavy baryon carry less momentum than those inside a nucleon. This feature is more prominent as the heavy quark mass increases. We discuss the baryon sum rule, momentum sum rule, and the Bjorken spin sum rule for singly heavy baryons. We also discuss the inequality conditions for the quark distribution functions. In addition, we present the results for the light-quark quasi-distribution functions.

    hep-phhep-latPTEP(2023)·1 citation
25. 25*

    From the isovector molecular explanation of the newly $T_{c\bar{s}}^{a0(++)}(2900)$ to possible charmed-strange molecular pentaquarks

    Rui Chen🇨🇳 · Qi Huang🇨🇳

    In this work, we adopt the one-boson-exchange model to study the $D^{(\ast )}{K}^{(\ast )}$ interactions. With the same parameters, we can simultaneously reproduce the masses of the $D_{s0}(2317)$, $D_{s1}(2460)$, and $T_{c\bar{s}}^{a0(++)}(2900)$ recently observed by the LHCb collaboration in the hadronic molecular picture, where the $D_{s0}(2317)$, $D_{s1}(2460)$, and $T_{c\bar{s}}^{a0(++)}(2900)$ are regarded as the $DK[I(J^P)=0(0^{+})]$, $D^{\ast }K[0(1^{+})]$, and $D^{\ast }{K}^{\ast }[1(0^{+})]$ charmed-strange molecular states, respectively. In addition, we extend to study the ${\Lambda }_c{K}^{(\ast )}$ and ${\Sigma }_c{K}^{(\ast )}$ interactions and predict two possible charmed-strange molecular pentaquarks, the single ${\Sigma }_c{K}^{\ast }$ state with $I(J^P)=1/2(1/2^{-})$ and $3/2(3/2^{-})$. After considering the coupled channel effects, our results show that the coupled ${\Lambda }_c{K}^{\ast }/{\Sigma }_c{K}^{\ast }$ molecular state with $I(J^P)=1/2(1/2^{-})$ and the coupled ${\Sigma }_{c}K/{\Lambda }_c{K}^{\ast }$ molecular state with $I(J^P)=1/2(1/2^{-})$ can be good hadronic molecular candidates, the ${\Lambda }_c{K}^{\ast }({}^2{S}_{1/2})$ and ${\Sigma }_{c}K({}^2{S}_{1/2})$ are the dominant channels, respectively.

    hep-ph29 citations
26. 26*

    Study of the $\omega$/${\omega }_3$, $\rho$/${\rho }_3$ and the newly observed $\omega$-like state $X(2220)$

    Ya-Rong Wang🇨🇳 · Ting-Yan Li🇨🇳 · Zheng-Yuan Fang🇨🇳 · Hao Chen🇨🇳 · Cheng-Qun Pang🇨🇳

    We study the excited states of $\omega$ and ${\omega }_3$ by comparison with the $\rho$ and ${\rho }_3$ families, and discuss the possibility of $X(2220)$ as $\omega$ excitation by analyzing the mass spectra and strong decay behaviors. In addition, we predict the masses and widths of $\omega (2D)$ and ${\omega }_3$and ${\rho }_3(4D)$, ${\rho }_3(1G)$, ${\omega }_3$ and ${\rho }_3(2G)$ and ${\omega }_3(3G)$ and ${\rho }_3(3G)$. The abundant information of their two-body strong decays predicted in this work will be helpful to further study of these $\omega$ and ${\omega }_3$ and $\rho$ and ${\rho }_3$ states in experiment and theory.

    hep-phPRD(2022)·13 citations
27. 27*

    Medium effects for hadron-tagged jets in proton-proton collisions

    B.G. Zakharov

    We study the medium modification factor $I_{pp}$ within the light-cone path integral approach to induced gluon emission. We use parametrization of the running coupling ${\alpha }_s(Q,T)$ which has a plateau around $Q\sim \kappa T$. We calculate $I_{pp}$ with no free parameters using $\kappa$ fitted to the LHC data on the nuclear modification factor $R_{AA}$. We find that the theoretical multiplicity dependence of the ratio $I_{pp}/⟨I_{pp}⟩$ for $5.02$ TeV $pp$ collisions agrees reasonably with the recent preliminary data from ALICE [1].

    hep-phnucl-thPisma Zh.Eksp.Teor.Fiz.(2022)·6 citations
28. 28*

    Texture of Two Vanishing Subtraces in Neutrino Mass Matrix and Current Experimental Tests

    A. Ismael🇪🇬 · E. I. Lashin🇪🇬 · N. Chamoun🇸🇾

    We present a full phenomenological and analytical study for the neutrino mass matrix characterized by two vanishing $2\times 2$ subtraces. We update one past result in light of the recent experimental data. Out of the fifteen possible textures, we find seven cases can accommodate the experimental data instead of eight ones in the past study. We also introduce few symmetry realizations for viable and nonviable textures based on non-abelian ($A_4$ or $S_4$) flavor symmetry within type II seesaw scenario.

    hep-phPRD(2023)·6 citations
29. 29*

    Charmed baryon ${\Omega }_c^0\to {\Omega }^{-}{l}^{+}{\nu }_l$ and ${\Omega }_c^0\to {\Omega }_c^{-}{\pi }^{+}({\rho }^{+})$ decays in light cone sum rules

    T.M.Aliev🇹🇷 · S.Bilmis🇹🇷 · M.Savci🇹🇷

    The semileptonic ${\Omega }_c^0\to {\Omega }^{-}l\nu$ and non-leptonic ${\Omega }_c^0\to {\Omega }^{-}{\pi }^{+}$, ${\Omega }_c^0\to {\Omega }^{-}{\rho }^{+}$ decays of charmed ${\Omega }_c$ baryon are studied within the light cone sum rules. The form factors responsible for ${\Omega }_c\to \Omega$ transitions are calculated using the distribution amplitudes of ${\Omega }_c$ baryon. With the obtained form factors, the branching ratios of ${\Omega }_c^0\to {\Omega }^{-}{l}^{+}{\nu }_l$, ${\Omega }_c^0\to {\Omega }^{-}{\pi }^{+}$, and ${\Omega }_c^0\to {\Omega }^{-}{\rho }^{+}$ decays are estimated. The results are compared with Belle data as well as the findings of the other approaches.

    hep-phPRD(2022)·16 citations
30. 30*

    The Big Bang as a Mirror: a Solution of the Strong CP Problem

    Latham Boyle🇨🇦 · Martin Teuscher🇨🇦 · Neil Turok🇨🇦

    We argue that the Big Bang can be understood as a type of mirror. We show how reflecting boundary conditions for spinors and higher spin fields are fixed by local Lorentz and gauge symmetry, and how a temporal mirror (like the Bang) differs from a spatial mirror (like the AdS boundary), providing a possible explanation for the observed pattern of left- and right-handed fermions. By regarding the Standard Model as the limit of a minimal left-right symmetric theory, we obtain a new, cosmological solution of the strong $CP$ problem, without an axion.

    hep-phastro-ph.COgr-qchep-th14 citations
31. 31*

    The radiation emitted from axion dark matter in a homogeneous magnetic field, and possibilities for detection

    Shuo Xu🇨🇳 · Siyu Chen🇨🇳 · Hong-Hao Zhang🇨🇳 · Guangbo Long🇨🇳

    We study the direct radiation excited by oscillating axion (or axion-like particle) dark matter in a homogenous magnetic field and its detection scheme. We concretely derive the analytical expression of the axion-induced radiated power for a cylindrical uniform magnetic field. In the long wave limit, the radiation power is proportional to the square of the B-field volume and the axion mass $m_a$, whereas it oscillate as approaching the short wave limit and the peak powers are proportional to the side area of the cylindrical magnetic field and $m_a^{-2}$. The maximum power locates at mass $m_a\sim \frac{3\pi }{4R}$ for fixed radius $R$. Based on this characteristic of the power, we discuss a scheme to detect the axions in the mass range $1-10^4$\,neV, where four detectors of different bandwidths surround the B-field. The expected sensitivity for $m_a\lesssim 1\mu$eV under typical-parameter values can far exceed the existing constraints.

    hep-phastro-ph.COastro-ph.HEPRD(2022)·1 citation
32. 32*

    Probing compressed higgsinos with forward protons at the LHC

    Hang Zhou🇨🇳 · Ning Liu🇨🇳

    Supersymmetric models with nearly-degenerate light higgsinos provide a consistent solution to the naturalness problem under rigorous constraints from current experimental searches for sparticles. However, it is challenging to probe the compressed scenarios at collider experiments due to the hard-to-detect soft final states. To overcome this issue, strategies have been proposed to take advantage of the photon fusion along the ultraperipheral collision at the Large Hadron Collider, which are feasible with the forward detectors installed at the ATLAS and CMS detectors. In this paper, we demonstrate a search strategy for the chargino pair production via photon fusion at the 13 TeV LHC, realizing a good sensitivity that can exclude $m_{{\tilde{\chi }}_1^{\pm }}$ up to 270 GeV (308 GeV) for a mass splitting $\Delta m({\tilde{\chi }}_1^{\pm },{\tilde{\chi }}_1^0)\in [1,15]$ GeV with an integrated luminosity of 100 fb${}^{-1}$ (3 ab${}^{-1}$) at 95% C.L.

    hep-phJHEP(2022)·8 citations
33. 33*

    The carbon footprint of proposed ${\mathrm{e}}^{+}{\mathrm{e}}^{-}$ Higgs factories

    Patrick Janot🇨🇭 · Alain Blondel🇫🇷

    The energy consumption of any of the ${\mathrm{e}}^{+}{\mathrm{e}}^{-}$ Higgs factory projects that can credibly operate immediately after the end of LHC, namely three linear colliders (CLIC, operating at $\sqrt{s}=380$GeV; and ILC and ${\mathrm{C}}^3$, operating at $\sqrt{s}=250$ GeV) and two circular colliders (CEPC and FCC-ee, operating at $\sqrt{s}=240$ GeV), will be everything but negligible. Future Higgs boson studies may therefore have a significant environmental impact. This note proposes to include the carbon footprint for a given physics performance as a top-level gauge for the design optimization and, eventually, the choice of the future facility. The projected footprints per Higgs boson produced, evaluated using the 2021 carbon emission of available electricity, are found to vary by a factor 100 depending on the considered Higgs factory project.

    hep-phhep-exphysics.acc-phphysics.soc-phEur.Phys.J.Plus(2022)·15 citations
34. 34*

    Dark Grand Unification in the Axiverse: Decaying Axion Dark Matter and Spontaneous Baryogenesis

    Joshua W. Foster🇺🇸 · Soubhik Kumar🇺🇸 · Benjamin R. Safdi🇺🇸 · Yotam Soreq🇮🇱

    The quantum chromodynamics axion with a decay constant near the Grand Unification (GUT) scale has an ultralight mass near a neV. We show, however, that axion-like particles with masses near the keV - PeV range with GUT-scale decay constants are also well motivated in that they naturally arise from axiverse theories with dark non-abelian gauge groups. We demonstrate that the correct dark matter abundance may be achieved by the heavy axions in these models through the misalignment mechanism in combination with a period of early matter domination from the long-lived dark glueballs of the same gauge group. Heavy axion dark matter may decay to two photons, yielding mono-energetic electromagnetic signatures that may be detectable by current or next-generation space-based telescopes. We project the sensitivity of next-generation telescopes including $\text{Athena,}$ AMEGO, and e-ASTROGAM to such decaying axion dark matter. If the dark sector contains multiple confining gauge groups, then the observed primordial baryon asymmetry may also be achieved in this scenario through spontaneous baryogenesis. We present explicit orbifold constructions where the dark gauge groups unify with the SM at the GUT scale and axions emerge as the fifth components of dark gauge fields with bulk Chern-Simons terms.

    hep-phastro-ph.COhep-thJHEP(2022)·41 citations
35. 35*

    Baryogenesis from spontaneous CP violation in the early Universe

    S. J. Huber🇬🇧 · K. Mimasu🇬🇧 · J. M. No🇪🇸

    We propose a variant of electroweak-scale baryogenesis characterized by the spontaneous breaking of the charge-parity (CP) symmetry in the early Universe driven by the vacuum expectation value of a CP-odd scalar. This CP breaking period in the early Universe would be ended by the electroweak phase transition, with CP being (approximately) conserved at present, thus avoiding the stringent electric dipole moment experimental constraints on beyond-the-Standard-Model sources of CP violation. We study an explicit realization via a non-minimal Higgs sector consisting of two Higgs doublets and a singlet pseudoscalar (2HDM + $a$). We analyze the region of the 2HDM + $a$ parameter space where such an early Universe period of CP violation occurs, and show that the required thermal history and successful baryogenesis lead to a predictive scenario, testable by a combination of LHC searches and low-energy flavour measurements.

    hep-phPRD(2023)·22 citations
36. 36*

    One-loop Fierz Transformations

    Jason Aebischer🇨🇭 · Marko Pesut🇨🇭

    Fierz transformations for four-fermion operators are generalized to the one-loop level. A general renormalization scheme is used to compute QCD and QED corrections to the tree-level relations, which result from Fierz-evanescent operators. The results can be used to perform general one-loop basis transformations involving four-fermi and evanescent operators. We illustrate the usefulness of our results by discussing two examples from a matching calculation and a one-loop basis change.

    hep-phJHEP(2022)·28 citations
37. 37*

    On the nature of cosmic strings in the brane world

    Chia-Min Lin🇹🇼

    We investigate a static, cylindrically symmetric cosmic string on the brane without a perturbative approximation. We find there could be a (large) enhancement of the (effective) string tension when the energy density at the center of the string is (much) larger than twice the brane tension. We also point out a new way to evade the cosmic string problem when the energy density at the center of the string approaches twice the brane tension. These findings could have experimental and theoretical implications for searching for cosmic strings on the brane, in particular for cosmic strings generated after inflation (such as D-term inflation) on the brane.

    ↳ hep-thastro-ph.COgr-qchep-phChin.J.Phys.(2023)·4 citations
38. 38*

    Hadro-chemistry effects on charm decayed leptons in heavy-ion collisions

    Kai Lu🇨🇳 · Min He🇨🇳

    Charm-hadrons possess versatile hadro-chemistry as characterized by various transverse-momentum-dependent ratios between their different species. In particular, the charm hadro-chemistry may be modified in relativistic heavy-ion collisions with respect to proton-proton collisions at the same energy, as caused by novel diffusion and hadronization mechanisms of charm quarks in the environment of the created quark-gluon plasma (QGP) in the former. Inspired by recent measurements of leptons from charm-hadron decays (separated from bottom decays) in Pb-Pb and Au-Au collisions, we investigate the effects of the charm hadro-chemistry on the leptonic observables. We find that full consideration of charm hadro-chemistry in both proton-proton and heavy-ion collisions causes only mild change of charm-leptons' suppression factor with respect to previous calculations hadronizing charm quarks into $D$ mesons only, whereas the resulting change (increase) in the charm-leptons' elliptic flow turns out to be more pronounced as a consequence of the larger collectivity of ${\Lambda }_c$ baryons than $D$ mesons.

    ↳ nucl-thhep-phnucl-exPRC(2022)·0 citations
39. 39*

    High-precision QCD physics at FCC-ee

    Francesco Giuli🇨🇭

    The Future Circular Collider (FCC) is a post-LHC project aiming at direct and indirect searches for physics beyond the SM in a new 100 km tunnel at CERN. In addition, the FCC-ee offers unique possibilities for high-precision studies of the strong interaction in the clean environment provided by $e^{+}{e}^{-}$ collisions, thanks to its broad span of center-of-mass energies ranging from the Z pole to the top-pair threshold, and its huge integrated luminosities yielding $10^{12}$ and $10^8$ jets from Z and W bosons decays, respectively, as well as $10^5$ pure gluon jets from Higgs boson decays. In this contribution, we will summarize studies on the impact the FCC-ee will have on our knowledge of the strong force including: (i) QCD coupling extractions with per-mille uncertainties, (ii) parton radiation and parton-to-hadron fragmentation functions, (iii) jet properties (ligh-quark-gluon discrimination, $e^{+}{e}^{-}$ event shapes and multijet rates, jet substructure, etc.), (iv) heavy-quark jets (dead cone effect, charm-bottom separation, gluon $\to c\bar{c}$, $b\bar{b}$ splitting, etc.); and (v) non-perturbative QCD phenomena (color reconnection, baryon and strangeness production, Bose-Einstein and Fermi-Dirac final-state correlations, etc.).

    ↳ hep-exhep-phPoS(2022)·1 citation
40. 40*

    Effects of gravity in extra dimensions in atomic phenomena

    V. A. Dzuba🇦🇺 · V. V. Flambaum🇦🇺 · P. Munro-Laylim🇦🇺

    We use the difference between theory and experiment for energy intervals in simple atomic systems (hydrogen, muonium, positronium and deuteron) to find limits on the size of extra space dimensions in the Arkani-Hamed - Dimopoulos - Dvali model for gravitation potential on short distances. As an additional experimental fact we use absence of the small size gravitational bound states of elementary particles. We demonstrate that the perturbation theory approach does not work and more reliable results are obtained by solving the Dirac equations for an electron in Coulomb and gravitational fields. These results probe smaller distances than distance between nuclei in molecules and the limits are significantly stronger than the limits on the size of extra dimensions obtained using spectra of hydrogen molecules.

    ↳ physics.atom-phhep-phhep-thPRA(2022)·8 citations
41. 41*

    Analysis of the interaction between $\varphi$ meson and nucleus

    Xiao-Yun Wang🇨🇳 · Chen Dong🇨🇳 · Quanjin Wang🇨🇳

    In this work, we systematically study the $\varphi$ meson and nucleus interaction by analyzing and fitting the cross sections of $\gamma N$$\to \varphi$$N$ ($N$ represent the nucleus) reactions near the threshold. With the help of vector meson dominant model, the distribution of $\varphi$-$N$ scattering length as a function of energy is presented, and the results show that there is a slight increase in scattering length with increasing energy. Based on this, the average scattering length of $\varphi$-proton is obtained as $0.10\pm 0.01$ fm by combining experimental data and theoretical models. Moreover, the average scattering length of $\varphi$-deuteron interaction is derived to be $0.014\pm 0.002$ fm for the first time. Further, the effect of the momentum transfer $|t_{min}|$ on the $\varphi$-$N$ scattering length at the threshold is discussed. The obtained results not only provide important theoretical information for a more comprehensive and accurate study of the $\varphi$-$N$ scattering length, but also provide a basis for future experimental measurements of $\varphi$ meson production.

    ↳ nucl-thhep-phCPC(2023)·9 citations
42. 42*

    Gauge Theory Couplings on Anisotropic Lattices

    Marcela Carena🇺🇸 · Erik J. Gustafson🇺🇸 · Henry Lamm🇺🇸 · Ying-Ying Li🇺🇸 · Wanqiang Liu🇺🇸

    The advantage of simulating lattice field theory with quantum computers is hamstrung by the limited resources that induce large errors from finite volume and sizable lattice spacings. Previous work has shown how classical simulations near the Hamiltonian limit can be used for setting the lattice spacings in real-time through analytical continuation, thereby reducing errors in quantum simulations. In this work, we derive perturbative relations between bare and renormalized quantities in Euclidean spacetime at any anisotropy factor -- the ratio of spatial to temporal lattice spacings -- and in any spatial dimension for $U(N)$ and $SU(N)$. This reduces the required classical preprocessing for quantum simulations. We find less than $10\%$ discrepancy between our perturbative results and those from existing nonperturbative determinations of the anisotropy for $SU(2)$ and $U(1)$ gauge theories. For the discrete groups ${\mathbb{Z}}_{10}$, ${\mathbb{Z}}_{100}$ and $\mathbb{BI}$, we perform lattice Monte Carlo simulations to extract anisotropy factors and observe similar agreement with our perturbative results.

    ↳ hep-lathep-phquant-phPRD(2022)·35 citations
43. 43*

    Towards a Localised S-Matrix Theory

    Dimitrios Karamitros🇬🇧 · Apostolos Pilaftsis🇬🇧

    We formulate an S-matrix theory in which localisation effects of the particle interactions involved in a scattering process are consistently taken into account. In the limit of an infinite spread of all interactions, the S-matrix assumes its standard form. To better understand the significance of the emerging quantum phenomena in this formalism, we consider a solvable field-theoretic model with spatial Gaussian spreads at the interaction vertices. This solvable model, which was previously introduced in the literature, enables accurate descriptions of detection regions that are either close to or far from the source. In close analogy with light diffraction in classical optics, we call these two regions near-field and far-field zones, or the Fresnel and Fraunhofer regions. We revisit the question whether mixed mediators produce an oscillating pattern if their detection occurs in the Fresnel region. Besides corroborating certain earlier findings of the S-matrix amplitude in the forward Fresnel and Fraunhofer regimes, we observe several novel features with respect to its angular dependence which have not been accounted before in the literature. In particular, we obtain a ``quantum obliquity factor'' that suppresses particle propagation in the backwards direction, thereby providing an explicit quantum field-theoretic description for its origin in diffractive optics. Present and future colliders, as well as both short and long baseline neutrino experiments, would greatly benefit from the many predictions that can be offered from such a holistic localised S-matrix theory.

    ↳ hep-thhep-phquant-phPRD(2023)·11 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.