AlphaAlpha scattering, chiral symmetry and {sup 8}Be lifetime
Abstract
Alphaalpha scattering is discussed in terms of a chiral two pion exchange potential (TPE) which turns out to be attractive and singular at the origin, hence demanding renormalization. When {sup 8}Be is treated as a resonance state a model independent correlation between the Qfactor and lifetime 1/{gamma} for the decay into two alpha particles arises. For a wide range of parameters compatible with potential model analyses of low energy {pi}{alpha} scattering it is found {gamma} = 4.4(4)eV in fairly good agreement with the experimental value {gamma}{sub exp.} = 5.57(25)eV. The remaining discrepancy as well as the phase shift up to E{sub LAB} = 15 MeV could be accommodated by the leading nuclear peripheral contributions due to the {sup 3}H+p and {sup 3}He+n continuum.
 Authors:
 Departamento de Fisica Atomica, Molecular y Nuclear Universidad de Granada E18071 Granada (Spain)
 Publication Date:
 OSTI Identifier:
 21149155
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: AIP Conference Proceedings; Journal Volume: 1030; Journal Issue: 1; Conference: SCADRON70: Workshop on scalar mesons and related topics honoring Michael Scadron's 70. birthday, Lisbon (Portugal), 1116 Feb 2008; Other Information: DOI: 10.1063/1.2973487; (c) 2008 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ALPHA DECAY; ALPHA PARTICLES; ALPHA REACTIONS; BERYLLIUM 8; CHIRAL SYMMETRY; CHIRALITY; CORRELATIONS; HELIUM 3; HELIUM 4 TARGET; LIFETIME; MEV RANGE; NUCLEAR DECAY; PHASE SHIFT; PIONS; POTENTIALS; RENORMALIZATION; RESONANCE PARTICLES; SCATTERING
Citation Formats
Ruiz Arriola, E. AlphaAlpha scattering, chiral symmetry and {sup 8}Be lifetime. United States: N. p., 2008.
Web. doi:10.1063/1.2973487.
Ruiz Arriola, E. AlphaAlpha scattering, chiral symmetry and {sup 8}Be lifetime. United States. doi:10.1063/1.2973487.
Ruiz Arriola, E. 2008.
"AlphaAlpha scattering, chiral symmetry and {sup 8}Be lifetime". United States.
doi:10.1063/1.2973487.
@article{osti_21149155,
title = {AlphaAlpha scattering, chiral symmetry and {sup 8}Be lifetime},
author = {Ruiz Arriola, E.},
abstractNote = {Alphaalpha scattering is discussed in terms of a chiral two pion exchange potential (TPE) which turns out to be attractive and singular at the origin, hence demanding renormalization. When {sup 8}Be is treated as a resonance state a model independent correlation between the Qfactor and lifetime 1/{gamma} for the decay into two alpha particles arises. For a wide range of parameters compatible with potential model analyses of low energy {pi}{alpha} scattering it is found {gamma} = 4.4(4)eV in fairly good agreement with the experimental value {gamma}{sub exp.} = 5.57(25)eV. The remaining discrepancy as well as the phase shift up to E{sub LAB} = 15 MeV could be accommodated by the leading nuclear peripheral contributions due to the {sup 3}H+p and {sup 3}He+n continuum.},
doi = {10.1063/1.2973487},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1030,
place = {United States},
year = 2008,
month = 8
}

Smallangle polarization in highenergy [ital p][ital p] scattering through nonperturbative chiral symmetry breaking
We show that a large anomalous contribution to the axial charge of the proton due to nonperturbative instantonlike gluonic field configurations implies highenergy spin effects in [ital p][ital p] elastic scattering. This is the same mechanism which is responsible for anomalous baryon number violation at high energy in the standard model. We compute the proton polarization due to these effects and we show that it is proportional to the centerofmass scattering angle with a universal (energy independent) slope of order unity.