A narrow and strong structure due to S-wave πNN dynamics near threshold

The structure of the unbound nuclei 9 He , 10 Li and 13 Be has been explored using breakup and proton-knockout from intermediate energy 11 Be and 14,15 B beams. In the case of both N = 7 isotones, virtual s-wave strength is observed near threshold together with a higher-lying resonance. A very narrow structure at threshold in the 12 Be + n relative energy spectrum is demonstrated to arise from the decay of the 14 Be *(2+), discounting earlier reports of a strong virtual s-wave state in 13 Be .

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Threshold Behaviour of (e, 2e) Reactions in Classical and Quantum Mechanics

Australian Journal of Physics ◽

10.1071/ph98091 ◽

1999 ◽

Vol 52 (3) ◽

pp. 323 ◽

Cited By ~ 7

Author(s):

H. Friedrich ◽

W. Ihra ◽

P. Meerwald

Keyword(s):

Quantum Mechanics ◽

Coulomb Field ◽

Wave Model ◽

Threshold Region ◽

Classical Dynamics ◽

S Wave ◽

Impact Ionisation ◽

Classical Phase Space ◽

Classical And Quantum Mechanics ◽

Near Threshold

Electron impact ionisation of one-electron atoms or ions is well described in the near threshold region by Wannier’s theory based on estimating the classical phase space available to two outgoing electrons in the Coulomb field of the residual ion. The relation between classical dynamics and quantum mechanics in the near threshold region becomes more complicated and interesting in ‘non-Wannier situations’, where classical ionisation is either strictly forbidden or strongly inhibited. This paper focusses on two examples of such situations, which have been receiving increasing attention in recent years, namely the s-wave model and the case where the exponent in Wannier"s law diverges.

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S-wave η′-proton FSI; phenomenological analysis of near-threshold production of π0, η, and η′ mesons in proton-proton collisions

Physics Letters B ◽

10.1016/s0370-2693(00)00533-5 ◽

2000 ◽

Vol 482 (4) ◽

pp. 356-362 ◽

Cited By ~ 63

Author(s):

P Moskal ◽

H.-H Adam ◽

J.T Balewski ◽

A Budzanowski ◽

J Budziński ◽

...

Keyword(s):

Phenomenological Analysis ◽

S Wave ◽

Proton Proton ◽

Proton Collisions ◽

Proton Proton Collisions ◽

Near Threshold

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Compositeness of hadron resonances in chiral dynamics

International Journal of Modern Physics E ◽

10.1142/s0218301314610035 ◽

2014 ◽

Vol 23 (07) ◽

pp. 1461003 ◽

Cited By ~ 1

Author(s):

Tetsuo Hyodo

Keyword(s):

Renormalization Constant ◽

Effective Range ◽

S Wave ◽

Independent Manner ◽

Range Parameter ◽

Model Independent ◽

Threshold Resonances ◽

Field Renormalization ◽

Near Threshold ◽

Hadronic States

Recent experimental observations of many unconventional hadronic states stimulate an interest in the structure of hadrons. While various internal configurations have been proposed, it is a subtle problem to identify the structure of hadron resonances in a model independent manner. Here we discuss the composite/elementary nature of hadrons using the field renormalization constant Z. In particular, we show that the magnitude of the effective range parameter re is related to the structure of s-wave near-threshold resonances.

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OBSERVATION OF $p\bar{p}$, $p\bar{\Lambda}$, $K^-\bar{\Lambda}$ NEAR-THRESHOLD ENHANCEMENT AT BES

International Journal of Modern Physics A ◽

10.1142/s0217751x05023797 ◽

2005 ◽

Vol 20 (08n09) ◽

pp. 1985-1989 ◽

Cited By ~ 22

Author(s):

◽

HONGXUN YANG

Keyword(s):

Mass Spectrum ◽

Invariant Mass ◽

Confidence Level ◽

Invariant Mass Spectrum ◽

Total Width ◽

S Wave ◽

Threshold Enhancement ◽

Peak Mass ◽

Near Threshold

We observe a narrow enhancement near 2mp in the invariant mass spectrum of [Formula: see text] pairs from radiative [Formula: see text] decays. In the case of S-wave fit, the peak mass is below 2mp at [Formula: see text] and the total width is Γ<30MeV at the 90% confidence level. And we also find near-threshold enhancement in the invariant mass spectrum of [Formula: see text] in [Formula: see text] decays. The mass is m=2075±12(stat)±5(syst)MeV and width is Γ=90±35(stat)±9(syst)MeV. A [Formula: see text] near-threshold enhancement is also studied and it has m=1.50~1.65GeV, Γ=70~110MeV with [Formula: see text].

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np → ηd near threshold and the s -wave ηN amplitude

The European Physical Journal A ◽

10.1140/epja/i2008-10662-x ◽

2008 ◽

Vol 38 (2) ◽

pp. 209-217 ◽

Cited By ~ 5

Author(s):

H. Garcilazo ◽

M. T. Peña

Keyword(s):

S Wave ◽

Near Threshold

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Hearing in Mice via GSR Audiometry

Journal of Speech and Hearing Research ◽

10.1044/jshr.0604.359 ◽

1963 ◽

Vol 6 (4) ◽

pp. 359-368 ◽

Cited By ~ 34

Author(s):

Charles I. Berlin

Keyword(s):

Inverse Relationship ◽

Sound Pressure ◽

Single Units ◽

Sensitivity Curve ◽

Basic Tool ◽

Eighth Nerve ◽

Pure Tones ◽

Conditioned Responses ◽

Frequency Intensity ◽

Near Threshold

Hearing in mice has been difficult to measure behaviorally. With GSR as the basic tool, the sensitivity curve to pure tones in mice has been successfully outlined. The most sensitive frequency-intensity combination was 15 000 cps at 0-5 dB re: 0.0002 dyne/cm 2 , with responses noted from 1 000 to beyond 70 000 cps. Some problems of reliability of conditioning were encountered, as well as findings concerning the inverse relationship between the size of GSR to unattenuated tones and the sound pressure necessary to elicit conditioned responses at or near threshold. These data agree well with the sensitivity of single units of the eighth nerve of the mouse.

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