| Records |
| Author |
Wang, Y.F.; Yao, D.L.; Zheng, H.Q. |
| Title |
On the existence of N*(890) resonance in S-11 channel of N scatterings |
Type |
Journal Article |
| Year |
2019 |
Publication |
Frontiers of Physics |
Abbreviated Journal |
Front. Phys. |
| Volume |
14 |
Issue |
2 |
Pages |
24501 - 6pp |
| Keywords |
dispersion relations; N scatterings; nucleon resonance |
| Abstract |
Low-energy partial-wave N scattering data is reexamined with the help of the production representation of partial-wave S matrix, where branch cuts and poles are thoroughly under consideration. The left-hand cut contribution to the phase shift is determined, with controlled systematic error estimates, by using the results of O(p(3)) chiral perturbative amplitudes obtained in the extended-onmass- shell scheme. In S-11 and P-11 channels, severe discrepancies are observed between the phase shift data and the sum of all known contributions. Statistically satisfactory fits to the data can only be achieved by adding extra poles in the two channels. We find that a S-11 resonance pole locates at zr = (0:895-0:081)-(0:164-0:023)i GeV, on the complex s-plane. On the other hand, a P-11 virtual pole, as an accompanying partner of the nucleon bound-state pole, locates atzv = (0:966-0:018) GeV, slightly above the nucleon pole on the real axis below threshold. Physical origin of the two newly established poles is explored to the best of our knowledge. It is emphasized that the O(p(3)) calculation greatly improves the fit quality comparing with the previous O(p(2)) one. |
| Address |
[Wang, Yu-Fei; Zheng, Han-Qing] Peking Univ, Dept Phys, Beijing 100871, Peoples R China, Email: deliang.yao@ific.uv.es |
| Corporate Author |
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Thesis |
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| Publisher |
Higher Education Press |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
2095-0462 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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Notes  |
WOS:000454564100001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3857 |
| Permanent link to this record |
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| Author |
Aliaga, R.J.; Guirao, A.J. |
| Title |
On the preserved extremal structure of Lipschitz-free spaces |
Type |
Journal Article |
| Year |
2019 |
Publication |
Studia Mathematica |
Abbreviated Journal |
Studia Math. |
| Volume |
245 |
Issue |
1 |
Pages |
1-14 |
| Keywords |
concave space; extremal structure; Lipschitz-free space; Lipschitz function; metric alignment; preserved extreme point |
| Abstract |
We characterize preserved extreme points of the unit ball of Lipschitz-free spaces F (X) in terms of simple geometric conditions on the underlying metric space (X, d). Namely, the preserved extreme points are the elementary molecules corresponding to pairs of points p, q in X such that the triangle inequality d (p, q) <= d (p, r) + d (q, r) is uniformly strict for r away from p, q. For compact X, this condition reduces to the triangle inequality being strict. As a consequence, we give an affirmative answer to a conjecture of N. Weaver that compact spaces are concave if and only if they have no triple of metrically aligned points, and we show that all extreme points are preserved for several classes of compact metric spaces X, including Holder and countable compacta. |
| Address |
[Aliaga, Ramon J.; Guirao, Antonio J.] Univ Politecn Valencia, Inst Univ Matemat Pura & Aplicada, Camino Vera S-N, E-46022 Valencia, Spain, Email: raalva@upvnet.upv.es; |
| Corporate Author |
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Thesis |
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| Publisher |
Polish Acad Sciences Inst Mathematics-Impan |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0039-3223 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000446980500001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ pastor @ |
Serial |
3753 |
| Permanent link to this record |
