English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The charge-symmetry-breaking amplitudes for the recently observed d d ->alpha pi0 reaction are investigated. Chiral perturbation theory is used toclassify and identify the leading-order terms. Specific forms of the relatedone- and two-body tree level diagrams are derived. As a first step toward afull calculation, a few tree-level two-body diagrams are evaluated at eachconsidered order, using a simplified set of d and alpha wave functions and aplane-wave approximation for the initial dd state. The leading-orderpion-exchange term is shown to be suppressed in this model because of pooroverlap of the initial and final states. The higher-order one-body andshort-range (heavy-meson-exchange) amplitudes provide better matching betweenthe initial and final states and therefore contribute significantly andcoherently to the cross section. The consequences this might have for a fullcalculation, with realistic wave functions and a more complete set ofamplitudes, are discussed.Comment: REVTeX 4, 35 pages, 8 eps figures, submitted to PR

physical review. c. nuclear physics/physical review. c, nuclear physics

Survey of charge symmetry breaking operators for<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi>d</mml:mi><mml:mi>d</mml:mi><mml:mo>→</mml:mo><mml:mi>α</mml:mi><mml:msup><mml:mi>π</mml:mi><mml:mn>0</mml:mn></mml:msup></mml:mrow></mml:math>

Survey of charge symmetry breaking operators fordd→απ0