Inclusive Reactions Research Articles

Inclusive reactions from finite Minkowski spacetime correlation functions

The need to determine scattering amplitudes of few-hadron systems for arbitrary kinematics expands a broad set of subfields of modern-day nuclear and hadronic physics. In this work, we expand upon previous explorations on the use of real-time methods, like quantum computing or tensor networks, to determine few-body scattering amplitudes. Such calculations must be performed in a finite Minkowski spacetime, where scattering amplitudes are not well defined. Our previous work presented a conjecture of a systematically improvable estimator for scattering amplitudes constructed from finite-volume correlation functions. Here we provide further evidence that the prescription works for larger kinematic regions than previously explored as well as a broader class of scattering amplitudes. Finally, we devise a new method for estimating the order of magnitude of the error associated with finite time separations needed for such calculations. In units of the lightest mass of the theory, we find that to constrain amplitudes using real-time methods within O(10%), the spacetime volumes must satisfy mL∼O(10–102)) and mT∼O(102–104). Published by the American Physical Society 2024

Application of the semiclassical distorted wave model to the inclusive (d, d′x) reaction

We apply the semiclassical distorted wave model to the deuteroninduced inclusive (d, d′x) reaction. The calculated double differential cross sections (DDXs) as a function of the deuteron emission energy and the scattering angle are compared with experimental data. The calculated DDXs reasonably reproduce experimental data in the small energy-transfer region and at the forward angles. It is found that the refraction, which is the changes in the kinematics of the deuteron inside a nucleus, is necessary to reasonably reproduce the experimental data. We show that the refraction causes the increase/decrease in the differential cross section of the elementary process, hence the DDX.

Should You Put an Emoticon on Your Flag? How Subliminal Visual Stimuli Can Change Political Opinions

AbstractPolitical objects, like national flags, arouse emotions even when they are subliminal stimuli. Through two experiments that show subliminal stimuli to the subjects, this article analyzes if those emotions are positive or negative ones—that is to say, if they enhance an inclusive reaction or an excluding one. Besides, the article compares the intensity of the flag’s emotional effect with that of the emoticons, which are figures intended to represent emotional reactions or states. Findings confirm that the Spanish flag, as a subliminal stimulus, influences the opinions of the participants. However, it has had a lower effect than that obtained in previous, similar experiments. Emoticons produce a much more intense type of response than flags. The experiments (n = 85; n = 126) enlarge the knowledge about the emotional effects of political objects of nonconscious perception. Besides, we present an original methodological contribution: the use of emoticons to alter political views.

Comparison of Ichimura-Austern-Vincent and Glauber models for the deuteron-induced inclusive breakup reaction in light and medium-mass nuclei

Comparison of Ichimura-Austern-Vincent and Glauber models for the deuteron-induced inclusive breakup reaction in light and medium-mass nuclei

Applying Quantum Tomography to Hadronic Interactions

A proper description of inclusive reactions is expressed with density matrices. Quantum tomography reconstructs density matrices from experimental observables. We review recent work that applies quantum tomography to practical experimental data analysis. Almost all field-theoretic formalism and modeling used in a traditional approach is circumvented with great efficiency. Tomographically-determined density matrices can express information about quantum systems which cannot in principle be expressed with distributions defined by classical probability. Topics such as entanglement and von Neumann entropy can be accessed using the same natural language where they are defined. A deep relation exists between separability, as defined in quantum information science, and factorization, as defined in high energy physics. Factorization acquires a non-perturbative definition when expressed in terms of a conditional form of separability. An example illustrates how to go from data for momentum 4-vectors to a density matrix while bypassing almost all the formalism of the Standard Model.

Multiplicity trigger detector for the S[formula omitted]RIT experiment

A multiplicity trigger detector (MTD) was developed for the SπRIT experiment that aims to probe the high-density symmetry energy via heavy-ion collisions (HICs). The MTD is designed to measure the charged-particle multiplicity in HICs to provide a trigger signal that can be used to select high-multiplicity events induced by central collisions. The MTD consists of two side-walls segmented into 30 plastic scintillation paddles, each equipped with a multi-pixel photon counter. A custom board with EASIROC front-end ASIC is used as readout electronics. A multiplicity logic signal is generated by an on-board FPGA that processes the discriminated signals from EASIROCs. The overall latency of the whole detector system for outputting the trigger is less than 100ns, including 52ns of electronics latency for processing the signals. During the measurement of 112Sn+124Sn reactions at an incident energy of 270MeV/nucleon, the minimum multiplicity threshold of the MTD was set to 4, where the overall trigger efficiency was obtained to be about 39% for inclusive nuclear reactions. A simulation study with a numerical calculation of HICs found that the central collisions of impact parameters of less than 4fm can be triggered with a high efficiency of more than 95% by the experimental trigger condition.

Coulomb breakup reaction of loosely bound F17 with dynamic polarization potentials

We investigate the elastic scattering, inelastic scattering, breakup reaction, and total fusion reactions of the $^{17}\mathrm{F}+^{208}\mathrm{Pb}$ system using an optical model approach by including the dynamical polarization potential. In particular, we focus on the breakup reaction channels, whose effects on other reactions have been argued to be small. By exploiting two different potentials composed of a surface-type Woods-Saxon potential, which were obtained by a fitting analysis, and a Love-type optical potential, the breakup reaction cross sections are explained with other elastic and quasielastic scattering cross sections. For the breakup reaction at ${E}_{\text{lab}}=170$ MeV in the forward angle region, where only exclusive reaction data are known, inclusive breakup reaction data are deduced from available theoretical and experimental $E1$ strength values. We discuss the breakup reaction effects on the other nuclear reactions related to the $^{17}\mathrm{F}$ projectile in detail.

Neutrino-nucleus scattering in the SuSA model

The super-scaling approach (SuSA) model, based on the analogies between electron and neutrino interactions with nuclei, is reviewed and its application to the description of neutrino-nucleus scattering is presented. The contribution of both one- and two-body relativistic currents is considered. The model is validated with the (e,e') data, including also inelastic contributions for the inclusive reaction. A discussion of semi-inclusive reactions and their implications for charge-changing reactions of neutrinos is also presented. A selection of results for the inclusive neutrino reactions with change of charge is presented where theoretical predictions are compared with cross-section measurements from the main ongoing neutrino oscillation experiments.

Hunting BFKL in semi-hard reactions at the LHC

The agreement between calculations inspired by the resummation of energy logarithms, known as BFKL approach, and experimental data in the semi-hard sector of QCD has become manifest after a wealthy series of phenomenological analyses. However, the contingency that the same data could be concurrently portrayed at the hand of fixed-order, DGLAP-based calculations, has been pointed out recently, but not yet punctually addressed. Taking advantage of the richness of configurations gained by combining the acceptances of CMS and CASTOR detectors, we give results in the full next-to-leading logarithmic approximation of cross sections, azimuthal correlations and azimuthal distributions for three distinct semi-hard processes, each of them featuring a peculiar final-state exclusiveness. Then, making use of disjoint intervals for the transverse momenta of the emitted objects, i.e. kappa -windows, we clearly highlight how high-energy resummed and fixed-order driven predictions for semi-hard sensitive observables can be decisively discriminated in the kinematic ranges typical of current and forthcoming analyses at the LHC. The scale-optimization issue is also introduced and explored, while the uncertainty coming from the use of different PDF and FF set is deservedly handled. Finally, a brief overview of JETHAD, a numerical tool recently developed, suited for the computation of inclusive semi-hard reactions is provided.

Applications of pT-xR Variables in Describing Inclusive Cross Sections at the LHC

Invariant inclusive single-particle/jet cross sections in p–p collisions can be factorized in terms of two separable pT dependences, a [pT−s] sector and an [xR−pT−s] sector. Here, we extend our earlier work by analyzing more extensive data to explore various s-dependent attributes and other systematics of inclusive jet, photon and single particle reactions. Approximate power laws in s, pT and xR are found. Physical arguments are given which relate observations to the underlying physics of parton–parton hard scattering and the parton distribution functions in the proton. We show that the A(s,pT) function, introduced in our earlier publication to describe the pT dependence of the inclusive cross section, is directly related to the underlying hard parton–parton scattering for jet production, with little influence from soft physics. In addition to the a function, we introduce another function, the F(s,xR) function that obeys radial scaling for inclusive jets and offers another test of the underlying parton physics. An application to heavy ion physics is given, where we use our variables to determine the transparency of cold nuclear matter to penetrating heavy mesons through the lead nucleus.

Medium effects in antikaon-induced Ξ− hyperon production on nuclei near threshold

We study the antikaon-induced inclusive cascade Ξ− hyperon production from 12C and 184W target nuclei near threshold within a nuclear spectral function approach. The approach describes incoherent direct Ξ− hyperon production in elementary K−p→K+Ξ− and K−n→K0Ξ− processes as well as takes into account the influence of the scalar nuclear K−, K+, K0, Ξ− and their Coulomb potentials on these processes. We calculate the absolute differential and total cross sections for the production of Ξ− hyperons off these nuclei at laboratory angles ≤ 45∘ by K− mesons with momenta of 1.0 and 1.3 GeV/c, which are close to the threshold momentum (1.05 GeV/c) for Ξ− hyperon production on the free target nucleon at rest. We also calculate the momentum dependence of the transparency ratio for the 184W/12C combination for Ξ− hyperons at these K− beam momenta. We show that the Ξ− differential and total (absolute and relative) production cross sections at the considered initial momenta reveal a distinct sensitivity to the variations in the scalar Ξ− nuclear potential at saturation density ρ0, studied in the paper, in the low-momentum region of 0.1–0.6 GeV/c. We also demonstrate that for the subthreshold K− meson momentum of 1.0 GeV/c there is, contrary to the case of its above threshold momentum of 1.3 GeV/c, a strong sensitivity of the transparency ratio for Ξ− hyperons to the considered changes in the Ξ− nuclear potential at all outgoing Ξ− momenta as well, which cannot be masked, as in the case of differential and total observables mentioned above, by that associated with the possible changes in the poorly known experimentally Ξ−N inelastic cross section. Therefore, the measurement of these absolute and relative observables in a dedicated experiment at the J-PARC Hadron Experimental Facility will provide valuable information on the Ξ− in-medium properties, which will be complementary to that deduced from the study of the inclusive (K−,K+) reactions at incident momenta of 1.6–1.8 GeV/c in the Ξ− bound and quasi-free regions.

Nuclear effects on the ρ meson produced in the inclusive photonuclear reaction

The hadronic properties of the $\rho$ meson produced in the inclusive photonuclear reaction have been investigated. The elementary reaction occurring in the nucleus is assumed as $\gamma N \to \rho^0 N$. The $\rho$ meson, while propagating through the nucleus, interacts with the nuclear particles, and therefore, the properties of the $\rho$ meson can be modified because of this interaction. Being a short-lived particle, the $\rho$ meson decays to various elementary particles, such as, $e^+e^-$, $\pi^+\pi^-$, .... etc. The $e^+e^-$ invariant mass, i.e., the $\rho$ meson mass, distribution spectra have been calculated to extract the information about the parameters, viz., mass and width, of the $\rho$ meson in the nucleus. The calculated results have been compared with the data reported from Jefferson Laboratory.

Quarkonium semiclassical transport in quark-gluon plasma: factorization and quantum correction

We study quarkonium transport in the quark-gluon plasma by using the potential nonrelativistic QCD (pNRQCD) effective field theory and the framework of open quantum systems. We argue that the coupling between quarkonium and the thermal bath is weak using separation of scales, so the initial density matrix of the total system factorizes and the time evolution of the subsystem is Markovian. We derive the semiclassical Boltzmann equation for quarkonium by applying a Wigner transform to the Lindblad equation and carrying out a semiclassical expansion. We resum relevant interactions to all orders in the coupling constant at leading power of the nonrelativistic and multipole expansions. The derivation is valid for both weakly coupled and strongly coupled quark-gluon plasmas. We find reaction rates in the transport equation factorize into a quarkonium dipole transition function and a chromoelectric gluon distribution function. For the differential reaction rate, the definition of the momentum dependent chromoelectric gluon distribution function involves staple-shaped Wilson lines. For the inclusive reaction rate, the Wilson lines collapse into a straight line along the real time axis and the distribution becomes momentum independent. The relation between the two Wilson lines is analogous to the relation between the Wilson lines appearing in the gluon parton distribution function (PDF) and the gluon transverse momentum dependent parton distribution function (TMDPDF). The centrality dependence of the quarkonium nuclear modification factor measured by experiments probes the momentum independent distribution while the transverse momentum dependence and measurements of the azimuthal angular anisotropy may be able to probe the momentum dependent one. We discuss one way to indirectly constrain the quarkonium in-medium real potential by using the factorization formula and lattice calculations. The leading quantum correction to the semiclassical transport equation of quarkonium is also worked out. The study can be easily generalized to quarkonium transport in cold nuclear matter, which is relevant for quarkonium production in eA collisions in the future Electron-Ion Collider.

Lagrange-mesh R -matrix method for inhomogeneous equations

The Lagrange-mesh $R$-matrix method is generalized to inhomogeneous equations. This method is numerically stable and efficient. It can be directly used for transfer reactions with the formalism discussed by Ascuitto and Glendenning [Phys. Rev. 181,1396 (1969)] and for inclusive breakup reactions modeled by Ichimura, Austern, and Vincent [Phys. Rev. C 32, 431 (1985)]. We first present a simple example to assess the method. Then the application to the $^{93}$Nb($d$,$pX$) non-elastic breakup is discussed.

Evaluation of measurements of pre-equilibrum nucleon-induced light ion emission from 100 to 200 MeV

The mutual consistency of experimental continuum energy spectra observed in nucleon-induced inclusive reactions in the incident energy range from 100 to 200 MeV, which lead to emission of light composite ejectiles such as 3He and α particles, is investigated. Studies to determine details of the reaction mechanism of pre-equilibrium reactions such as (p,α) often require experimental data which come from various sources. The accuracy of the measurements depends on the choice of experimental techniques and detectors employed, therefore it would be expected that the reliability of the generated data could vary. These issues are discussed and it is found that the fairly large sample of data from independent sources are reassuringly consistent. Interesting agreement between results induced by neutron and proton projectiles is found.

Inclusive neutrino-nucleus reaction cross sections at intermediate energies

Inclusive neutrino-nucleus reaction cross sections at intermediate energies (20 MeV < Ey < 500 MeV) are calculated throughout the periodic table for the most interesting nu­ clei from an experimental point of view. The method used had previously proved to be very accurate in calculating the induced reaction cross section for T=0 light nuclei (12C and 16O) and in the study of other similar processes like the ordinary muon capture. The electron-neutrino (ve) cross section weighted by the Michel distribution is also discussed in conjuction with the existing experimental results at LAMPF and ΚARMEN.

The neutron within the deuteron as a surrogate for neutron-induced reactions

We propose the use of neutron poisons in reactions induced by radioactive beams as a test of theoretical models aiming to relate neutron capture in nuclei with neutron surrogate reactions such as ([Formula: see text]) reactions. We exploit the approximations necessary to obtain a direct relation between the two reactions: surrogate versus neutron capture. We also show how this is intimately related to the momentum distribution of the neutron within the deuteron. The models we use are based on the theory of inclusive breakup reactions commonly employed in the treatment of incomplete fusion and surrogate method. Such theories were developed in the 1980s by Ichimura, Austern and Vincent [Phys. Rev. C 32 (1985) 431], Udagawa and Tamura [Phys. Rev. C 24 (1981) 1348] and Hussein and McVoy [Nucl. Phys. A 445 (1985) 124]. We use these theories to derive an expression for the proton yield in the reaction [Formula: see text]. The capture reaction [Formula: see text] is then extracted using reasonable approximations. By recalling an old method proposed by Serber [Phys. Rev. 80 (1950) 1098; Proc. Roy. Soc. A 208 (1951) 559] we explain how the momentum distribution of neutrons within the deuteron will depend on the short-range dependence of the nucleon–nucleon force. The relevance of our work to nucleosynthesis in the rapid neutron capture process is emphasized.

Absorption of $\omega$ and $\phi$ mesons in the inclusive photonuclear reaction

The $\omega$ and $\phi$ mesons dominantly decay outside the nucleus because the decay-lengths of them are much larger than the dimension of the nucleus. Therefore, the medium modification of the above mesons is studied through their absorption in the nucleus. CLAS collaboration at Jefferson Laboratory (Jlab) has investigated the absorption of the $\omega$ and $\phi$ mesons by measuring the nuclear transparency ratios for them in the $\gamma A \to \omega (\phi) X \to e^+e^-X$ reaction. The nuclear transparency ratios for both $\omega$ and $\phi$ mesons in the above reactions have been calculated, and those are compared with the experimental findings, reported from Jlab, to estimate the $\omega$ meson nucleon and $\phi$ meson nucleon cross sections in the nucleus.

Proton–neutron asymmetry independence of reduced single-particle strengths derived from (p,d) reactions

An overall reduction factor (ORF) is introduced for studying the quenching of single-particle strengths through nucleon transfer reactions. The ORF includes contributions of all the probed bound states of the residual nucleus in a transfer reaction and permits a proper comparison with results of inclusive knockout reactions. A systematic analysis is made with 103 sets of angular distribution data of (p,d) reactions on 21 even–even targets with atomic mass numbers from 8 to 56 using the consistent three-body model reaction methodology proposed in Lee et al. (2006) [25]. The extracted ORFs are found to be nearly independent on the proton–neutron asymmetry, which is different from the systematics of inclusive knockout reactions but is consistent with the recent measurement of (d,t), (d,He3), (p,2p), and (p,pn) reactions on nitrogen and oxygen isotopes and ab initio calculations.

Direct pickup and knockout processes in inclusive(p,dx) reactions at 42–392 MeV

Direct pickup and knockout processes in inclusive<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mo>(</mml:mo><mml:mi>p</mml:mi><mml:mo>,</mml:mo><mml:mi>d</mml:mi><mml:mi>x</mml:mi></mml:mrow></mml:math>) reactions at 42–392 MeV