Measurement of the mesonic decay branch of the <math><mrow><mover accent="true"><mi>K</mi><mo>¯</mo></mover><mi>N</mi><mi>N</mi></mrow></math> quasibound state

Measurement of the mesonic decay branch of the $\bar{K} N N$ quasibound state

Collaboration

Apr 2, 2024

15 pages

Published in:

e-Print:

DOI:

View in:

Abstract: (APS)

We conducted measurements of

K^{-} + {}^{3}{He} \to π Y N + N^{'}

reactions using a

1 GeV / c K^{-}

-beam, with the objective of understanding the broad decay width of

\bar{K} N N

(approximately twice as broad as that of

Λ (1405)

considered to be the

\bar{K} N

quasibound state). We successfully reproduced distributions of the

π Y N

invariant mass and momentum transfer for

π Y N

using model-fitting functions for

\bar{K} N N

formation and quasifree

\bar{K}

absorption (

{QF}_{\bar{K} - abs}

) processes. The model can describe the experimental data quite well, and four

\bar{K} N N \to π Y N

cross sections were obtained. The results indicate that mesonic decay is the dominant decay branch of

\bar{K} N N

. The results also suggest that

Γ_{π Λ N} \approx Γ_{π Σ N}

, which indicates that the

I_{\bar{K} N} = 1

absorption channel, in addition to the

I_{\bar{K} N} = 0

absorption channel, substantially contributes to the

\bar{K} N N

decay, making the

\bar{K} N N

state approximately twice as unstable as

Λ

(1405).

References(0)

Figures(13)

Loading ...