Three-body collision contributions to recombination and collision-induced dissociation. I. Cross sections

1998 ◽  
Vol 109 (16) ◽  
pp. 6701-6713 ◽  
Author(s):  
Russell T Pack ◽  
Robert B. Walker ◽  
Brian K. Kendrick
Keyword(s):  
Cross Sections ◽  
Collision Induced Dissociation ◽  
Three Body

scholarly journals Comment on “From Coulomb excitation cross sections to nonresonant astrophysical rates in three-body systems: The Ne17 case”

2020 ◽  
Vol 102 (6) ◽  
Author(s):  
J. Casal ◽  
M. Rodríguez-Gallardo ◽  
J. M. Arias ◽  
E. Garrido ◽  
R. de Diego
Keyword(s):  
Cross Sections ◽  
Coulomb Excitation ◽  
Excitation Cross Sections ◽  
Three Body

scholarly journals Measurements of neutron-induced light-charged particle emission reactions

2020 ◽  
Vol 239 ◽  
pp. 01001
Author(s):  
Guohui Zhang ◽  
Huaiyong Bai ◽  
Haoyu Jiang ◽  
Zengqi Cui ◽  
Yi Lu ◽  
...  
Keyword(s):  
Neutron Source ◽  
Neutron Energy ◽  
Cross Sections ◽  
Energy Region ◽  
Nuclear Research ◽  
Reaction Cross ◽  
Tandem Accelerator ◽  
Peking University ◽  
Three Body ◽  
Charged Particle Emission

In the past two decades cooperating with Frank Laboratory of Neutron Physics (FLNP), Joint Institute for Nuclear Research (JINR) measurements of (n, α) reaction cross sections for 6Li, 10B, 25Mg, 39K, 40Ca, 54,56,57 Fe, 58Ni, 63Cu, 64,67 Zn, 95Mo, 143Nd and 147,149 Sm nuclei were performed in the MeV neutron energy region based on the 4.5 MV Van de Graaff accelerator at Peking University. In recent years, our measurements were extended in three aspects. Firstly, measurements were expanded from two-body reactions to three-body reactions such as 10B (n, t2 α). Secondly, the neutron energy region was extended from below 8 MeV to 8 - 11 MeV by using the HI-13 tandem accelerator of China Institute of Atomic Energy (CIAE), with which cross sections of 54,56 Fe(n, α)53,51Cr reactions were measured. Thirdly, based on the newly-built China Spallation Neutron Source (CSNS) Back-n WNS (White Neutron Source), differential and angle-integrated cross sections for 6Li(n, t) and 10B(n, α) reactions were measured in the neutron energy region from 1 eV to 3 MeV.

scholarly journals Fiducial cross sections for the lepton-pair-plus-photon decay mode in Higgs production up to NNLO QCD

2022 ◽  
Vol 2022 (1) ◽  
Author(s):  
X. Chen ◽  
T. Gehrmann ◽  
E. W. N. Glover ◽  
A. Huss
Keyword(s):  
Higgs Boson ◽  
Decay Mode ◽  
Cross Sections ◽  
Gluon Fusion ◽  
Lepton Pair ◽  
Distinctive Features ◽  
Photon Decay ◽  
Higgs Decay ◽  
Decay Products ◽  
Three Body

Abstract The rare three-body decay of a Higgs boson to a lepton-antilepton pair and a photon is starting to become experimentally accessible at the LHC. We investigate how higher-order QCD corrections to the dominant gluon-fusion production process impact on the fiducial cross sections in this specific Higgs decay mode for electrons and muons. Corrections up to NNLO QCD are found to be sizeable. They are generally uniform in kinematical variables related to the Higgs boson, but display several distinctive features in the kinematics of its individual decay products.

Cross sections of the 10B(n,$\alpha$)7Li two-body and 10B(n, t2$\alpha$) three-body reactions at 4.0, 4.5, and 5.0 MeV

2019 ◽  
Vol 55 (11) ◽  
Author(s):  
Huaiyong Bai ◽  
Zhimin Wang ◽  
Haoyu Jiang ◽  
Zengqi Cui ◽  
Yiwei Hu ◽  
...  
Keyword(s):  
Cross Sections ◽  
Three Body

scholarly journals Numerical Simulations of Encounters of Hard Binaries

1985 ◽  
Vol 113 ◽  
pp. 335-338
Author(s):  
Seppo Mikkola
Keyword(s):  
Cross Sections ◽  
Transfer Rate ◽  
Binding Energies ◽  
Body System ◽  
Energy Transfer Rate ◽  
Orbital Elements ◽  
Numerical Integrations ◽  
Order Of Magnitude ◽  
Three Body ◽  
Theory And Experiments

Results from numerical integrations of random binary-binary encounters have been used to obtain various cross-sections and outcome distributions for the four-body scattering. The initial orbital elements were chosen randomly except the Kepler-energies for which various selected values were used. Rough estimates for mass effects were obtained by simulating encounters of binaries with unequal component masses.We developed a semi-analytical theory for obtaining the types and energies of the outcome configurations. The theory contains some adjustable parameters, the values of which we deduced by comparing the theory and experiments.The energy transfer rate by collisions (=outcome is not two binaries) dominates over that due to fly-by's by an order of magnitude, provided that the binaries are hard. The formation of a hierarchical three-body system is fairly common. In a collision of energetically similar very hard binaries the probability is about 20 percent, while it is greater than 50 percent if the binding energies differ by a factor of more than four.

COUPLED-CHANNELS ANALYSES OF 6He BREAKUP REACTIONS

2009 ◽  
Vol 24 (11) ◽  
pp. 2191-2197 ◽  
Author(s):  
T. MATSUMOTO ◽  
T. EGAMI ◽  
K. OGATA ◽  
Y. ISERI ◽  
M. KAMIMURA ◽  
...  
Keyword(s):  
Cross Sections ◽  
Reaction System ◽  
Basis Functions ◽  
Coulomb Breakup ◽  
Body Model ◽  
Coupled Channels ◽  
Gaussian Basis Functions ◽  
Three Body ◽  
Good Agreement ◽  
The Continuum

We present analyses of breakup effects of 6 He on the elastic scattering by the continuum-discretized coupled-channels method, in which the reaction system is described as a four-body model, n+n+4 He +target. In this analysis, three-body breakup continuum of 6 He is discretized by daiagonalizing the internal Hamiltonian of 6 He in a space spanned by the Gaussian basis functions. The calculated elastic cross sections are in good agreement with the experimental data, which shows that nuclear and Coulomb breakup effects are significant.

COLLISIONS OF LONG-LIVED EXCITED IONS OF OXYGEN AND NITROGEN

1964 ◽  
Vol 42 (11) ◽  
pp. 2086-2101 ◽  
Author(s):  
William McGowan ◽  
Larkin Kerwin
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Ion Beam ◽  
Collision Induced Dissociation ◽  
Ion Molecule Reactions ◽  
Collision Region ◽  
Mean Lifetime ◽  
New States ◽  
Product Ions

The role of some excited ions in laboratory ion–molecule reactions has been investigated, and their possible importance in the upper atmosphere considered. The mass spectrometer techniques of Aston banding and of comparing I.P. curves of parent and product ions have been applied to studies of collision-induced dissociation and charge exchange of oxygen and nitrogen in their parent gas. In every case studied, cross sections depended markedly upon the presence in the ion beam of ions in metastable or long-lived radiative states. In order that an ion reach the collision region, it had to have a mean lifetime greater than 3 μsec.The a 4Πu and b 4Σg excited states of O2+ were identified in the collision[Formula: see text]Higher states of O2+, which have not as yet been identified spectroscopically, were found in the collision[Formula: see text]The thresholds of these new states are 23.9, 27.9, 31.3, and 34.1 eV with an uncertainty ±0.2 eV. From the collision-induced dissociation of N2+, the A 2Πu and the [Formula: see text] states have been identified. Also, the reported transfer of the ν = 3 level of the B [Formula: see text] to the ν = 14 level of the A 2Πu was found.The cross section for 10/01 charged exchange of N2+ in N2 exhibited a marked decrease as excited-state ions diluted the beam. The 10/01 collisions of N+ in N2 and O+ in O2 exhibited an increase in cross section as metastables were added to the parent ion beam. The 10/20 reaction of O2+ in O2 was also observed to depend on excited O2+ ions.

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