scholarly journals KN scattering amplitude revisited in a chiral unitary approach and a possible broad resonance in S = +1 channel

2019 ◽  
Vol 2019 (1) ◽  
Author(s):  
Kenji Aoki ◽  
Daisuke Jido
Keyword(s):  
Cross Sections ◽  
Scattering Amplitude ◽  
Resonance State ◽  
Model Parameters ◽  
Broad Resonance ◽  
Total Cross Sections ◽  
Unitary Approach ◽  
Unitary Model ◽  
Chiral Unitary Approach ◽  
Energy Plane

Abstract We revisit the $KN$ scattering amplitude in order to investigate the possibility of the existence of a broad resonance in the $I=0$$KN$ channel around the energy of 1617 MeV with 305 MeV width. We use the chiral unitary model to describe the $KN$ scattering amplitudes and determine the model parameters so as to reproduce the differential cross sections of the $K^{+}N$ scatterings and the $I=0$ and 1 total cross sections up to $p_{\rm lab} = 800$ MeV/c, from which inelastic contributions start to be significant. Performing analytic continuation of the determined amplitude to the complex energy plane, we find a pole for a broad resonance state. We point out that the rapid increase appearing in the $I=0$ total cross section around $p_{\rm lab}=500$ MeV/c is a hint of the possible broad resonance of strangeness $S=+1$.

scholarly journals Some Recent Results on High-Energy Proton Interactions

Particles ◽  
2019 ◽  
Vol 2 (1) ◽  
pp. 57-69 ◽  
Author(s):  
I. M. Dremin
Keyword(s):  
Cross Sections ◽  
Scattering Amplitude ◽  
High Energy ◽  
Unitarity Condition ◽  
Total Cross Sections ◽  
Energy Proton ◽  
Elastic Scattering Amplitude ◽  
Energy Behavior ◽  
Impact Parameter Space ◽  
The Impact

Recent experimental results about the energy behavior of the total cross sections, the share of elastic and inelastic contributions to them, the peculiar shape of the differential cross section and our guesses about the behavior of real and imaginary parts of the elastic scattering amplitude are discussed. The unitarity condition relates elastic and inelastic processes. Therefore it is used in the impact-parameter space to get some information about the shape of the interaction region of colliding protons by exploiting new experimental data. The obtained results are described.

scholarly journals GAUGE/STRING-GRAVITY DUALITY AND FROISSART BOUND

2005 ◽  
Vol 20 (06) ◽  
pp. 1286-1294
Author(s):  
KYUNGSIK KANG
Keyword(s):  
Cross Sections ◽  
Particle Physics ◽  
Scattering Amplitude ◽  
Conformal Symmetry ◽  
High Energy ◽  
Total Cross Sections ◽  
Regge Behavior ◽  
Energy Behavior ◽  
Gravity Duality ◽  
String Gravity

The gauge/string-gravity duality correspondence opened renewed hope and possibility to address some of the fundamental and non-perturbative QCD problems of in particle physics, such as hadron spectrum and Regge behavior of the scattering amplitude at high energies. One of the most fundamental and long-standing problems is the high energy behavior of the total cross-sections. According to a series of exhaustive tests by the COMPETE group, (1) total cross sections have a universal Heisenberg behavior in energy corresponding to the maximal energy behavior allowed by the Froissart bound, i.e., A+B ln 2(s/s0) with B~0.32 mb and s0~34.41 GeV2 for all reactions, and (2). The factorization relation among σpp,even, σγp and σγγ is well satisfied by experiments. I discuss the recent interesting application of the gauge/string-gravity duality of AdS/CFT correspondence with a deformed background metric so as to break the conformal symmetry that lead to the Heisenberg behavior of rising total cross sections, and present some preliminary results on the high energy QCD from Planckian scattering in AdS and black-hole production.

scholarly journals ON THE IMPORTANCE OF SECOND-ORDER RESPONSE SENSITIVITIES TO NUCLEAR DATA IN REACTOR PHYSICS UNCERTAINTY ANALYSIS

2021 ◽  
Vol 247 ◽  
pp. 15021
Author(s):  
Dan G. Cacuci
Keyword(s):  
Cross Sections ◽  
Neutron Transport ◽  
Nuclear Data ◽  
Expected Value ◽  
Second Order ◽  
Model Parameters ◽  
Response Distribution ◽  
Reactor Physics ◽  
Adjoint Sensitivity ◽  
Total Cross Sections

This invited keynote presentation compares the relative importance of 1st-order versus 2nd-order sensitivities of the leakage response of an OECD/NEA benchmark (polyethylene-reflected plutonium sphere) to the nuclear data characterizing this benchmark. The imprecisely known parameters underlying the neutron transport computational model for this benchmark include 180 group-averaged total microscopic cross sections, 21600 group-averaged scattering microscopic cross sections, 60 parameters describing the fission process, 30 parameters describing the fission spectrum, 10 parameters describing the system’s sources, and 6 isotopic number densities. Thus, this benchmark comprises 21886 1st-order sensitivities of the leakage response with respect to the model parameters, and 478,996,996 2nd-order sensitivities, of which 239,509,441 are distinct. The exact deterministic computation of all of these 1st- and 2nd-order sensitivities was made possible by the application of the Second-Order Adjoint Sensitivity Analysis Methodology (2nd-ASAM) developed by Cacuci. Thousands (out of the 32 400 elements) of the 2nd-order sensitivities of the leakage response with respect to the total cross sections turned out to be significantly larger than the largest corresponding 1st-order sensitivities, contrary to some previously held beliefs in the reactor physics community. Hence, it will be shown that neglecting the 2nd-order sensitivities to total cross sections would cause very large non-conservative errors by under-reporting the response’s variance and expected value. The 2nd-order sensitivities also cause the response distribution to be skewed towards positive values relative to the expected value, which, in turn, is significantly larger than the computed value of the leakage response. The result presented in this paper also underscore the need for obtaining reliable cross section covariance data, which are not available at this time.

scholarly journals THE POMERON AND ODDERON IN ELASTIC, INELASTIC AND TOTAL CROSS-SECTIONS AT THE LHC

2011 ◽  
Vol 26 (27n28) ◽  
pp. 4755-4771 ◽  
Author(s):  
L. L. JENKOVSZKY ◽  
A. I. LENGYEL ◽  
D. I. LONTKOVSKYI
Keyword(s):  
Simple Model ◽  
Cross Section ◽  
Cross Sections ◽  
Energy Region ◽  
Scattering Amplitude ◽  
Total Cross Sections ◽  
Regge Trajectories ◽  
Relative Contribution ◽  
Main Emphasis

A simple model for elastic diffractive hadron scattering, reproducing the dip-bump structure is used to analyze pp and [Formula: see text] scattering. The main emphasis is on the delicate and nontrivial dynamics in the dip-bump region, near t = -1 GeV 2. The simplicity of the model and the expected smallness of the absorption corrections enables one the control of various contributions to the scattering amplitude, in particular the interplay between the C-even and C-odd components of the amplitude, as well as their relative contribution, changing with s and t. The role of the nonlinearity of the Regge trajectories is scrutinized. The ratio of the real to imaginary parts of the forward amplitude, the ratio of elastic to total cross-sections and the inelastic cross-section are calculated. Predictions for the LHC energy region, where most of the existing models will be either confirmed or ruled out, are presented.

scholarly journals Study of Positron Impact Scattering from Methane and Silane Using an Analytically Obtained Static Potential with Correlation Polarization

Atoms ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 113
Author(s):  
Dibyendu Mahato ◽  
Lalita Sharma ◽  
Rajesh Srivastava
Keyword(s):  
Cross Sections ◽  
Scattering Amplitude ◽  
Theoretical Calculations ◽  
Model Potential ◽  
Positron Impact ◽  
Static Potential ◽  
Total Cross Sections ◽  
Atomic Orbitals ◽  
Shift Analysis ◽  
Molecular Wavefunctions

A detailed study of positron impact elastic scattering from methane and silane is carried out using a model potential consisting of static and polarization potentials. The static potential for the molecular target is obtained analytically by using accurate Gaussian molecular wavefunctions. The molecular orbitals are expressed as a linear combination of Gaussian atomic orbitals. Along with the analytically obtained static potential, a correlation polarization potential is also added to construct the model potential. Utilizing the model potential, the Schrödinger equation is solved using the partial wave phase shift analysis method, and the scattering amplitude is obtained in terms of the phase shifts. Thereafter, the differential, integrated and total cross sections are calculated. These cross-section results are compared with the previously reported measurements and theoretical calculations.

Pion-nucleon scattering at high energies

1966 ◽  
Vol 289 (1419) ◽  
pp. 500-508 ◽  
Keyword(s):  
Experimental Data ◽  
Cross Section ◽  
Charge Exchange ◽  
Cross Sections ◽  
Scattering Amplitude ◽  
Forward Scattering Amplitude ◽  
Nucleon Scattering ◽  
Total Cross Sections ◽  
High Energies ◽  
Pion Nucleon

The charge exchange forward scattering amplitude 1.1 1.2 using an interpolation of the total cross sections which includes the results presented by Dr Galbraith at this meeting. From F (-) follows a prediction for the charge exchange forward cross section (c.m. system) 1.3 which will be compared with the experimental data including those presented by Dr Falk-Vairant and Dr Guerriero.

NEW UNDERSTANDING OF THE DIFFRACTIVE SCATTERING OF HADRONS AT HIGH ENERGIES: THE BLACKENING AND INCREASING EFFECTIVE INTERACTION AREA OF THE PROTON

1992 ◽  
Vol 07 (28) ◽  
pp. 2559-2565 ◽  
Author(s):  
SAUL BARSHAY ◽  
PATRICK HEILIGER ◽  
DIETER REIN
Keyword(s):  
Cross Sections ◽  
Scattering Amplitude ◽  
Effective Interaction ◽  
High Energy ◽  
Total Cross Sections ◽  
Energy Process ◽  
High Energies ◽  
Diffractive Scattering ◽  
Richard Feynman ◽  
High Energy Process

A new structure for the high-energy diffractive scattering amplitude is derived in two complementary ways (one of them recently revealed as due to Richard Feynman). Total cross-sections increase, due to a blackening of the interaction and also due to an effect which leads to an increase in the effective interaction area at fixed opacity. These features are dynamically related to the dominant high-energy process of multiparticle production.

Measurement of total cross sections (e+, Ne) and (e+, Ar)

1976 ◽  
Vol 54 (17) ◽  
pp. 1741-1748 ◽  
Author(s):  
J-S. Tsai ◽  
L. Lebow ◽  
D. A. L. Paul
Keyword(s):  
Total Cross Section ◽  
Cross Section ◽  
Cross Sections ◽  
Scattering Amplitude ◽  
Scattering Length ◽  
Forward Scattering Amplitude ◽  
Sum Rule ◽  
Total Cross Sections ◽  
Scattering Lengths ◽  
Momentum Integral

The total cross sections for positrons on neon and argon atoms have been measured in the energy ranges 15 eV to 272.5 eV and 25 eV to 300 eV respectively. The cross sections indicate clearly that Born values will not be reached until at least 3 KeV. Interpolating between the measured and the valid Born regions has allowed an application of the sum rule which connects scattering length. Born forward scattering amplitude, and the momentum-integral over the total cross section. This procedure gives scattering lengths as = −0.53 ± 0.15 Bohr radii for neon and as = −2.8 ± 0.7 Bohr radii for argon; the errors include maximum credible uncertainties in the interpolations.

scholarly journals Photoproduction of Pion Pairs at Moderate Energies

1977 ◽  
Vol 30 (6) ◽  
pp. 577
Author(s):  
T Chandramohan ◽  
K Venkatesan ◽  
P Achuthan
Keyword(s):  
Cross Sections ◽  
Scattering Amplitude ◽  
Lagrangian Model ◽  
Production Amplitude ◽  
Gauge Invariant ◽  
Total Cross Sections ◽  
Linearly Polarized ◽  
Polarized Photons

The problem of the production of pion pairs in photon-nucleon collisions is studied with the help of a new Lagrangian model. Using a relativistic covariant and gauge-invariant scattering amplitude based on a phenomenological Lagrangian, the differential and total cross sections are calculated for unpolarized and linearly polarized photons. The production amplitude incorporates terms involving 8(700), p(770), f(1260) and A(1236) resonances in addition to the nucleon and pion exchanges.

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