| Record |
Author  |
HADES Collaboration (Agakishiev, G. et al); Diaz, J.; Gil, A. |
| Title |
Deep sub-threshold K*(892)(0) production in collisions of Ar + KCl at 1.76A GeV |
Type |
Journal Article |
| Year |
2013 |
Publication |
European Physical Journal A |
Abbreviated Journal |
Eur. Phys. J. A |
| Volume |
49 |
Issue |
3 |
Pages |
34 - 7pp |
| Keywords |
|
| Abstract |
Results on the deep sub-threshold production of the short-lived hadronic resonance K*(892)(0) are reported for collisions of Ar + KCl at 1.76 A GeV beam energy, studied with the High Acceptance Di-Electron Spectrometer (HADES) at SIS18/GSI. The K*(892)(0) production probability per central collision of P-K*0 = (4.4 +/- 1.1 +/- 0.5) x 10(-4) and the K*(892)(0)/K-0 ratio of P-K*0/P-K0 = (1.9 +/- 0.5 +/- 0.3) x 10(-2) are determined at the lowest energy so far (i.e. deep below the threshold for the corresponding production in nucleon-nucleon collisions, root s(NN)-root s(thr) = -340MeV). The K*(0)/K-0 ratio is compared with results of other experiments and with the predictions of the UrQMD transport approach and of the statistical hadronization model. The experimental K*(0) yield and the K-*0/K-0 ratio are overestimated by the transport model by factors of about five and two, respectively. In a chemically equilibrated medium the ratio corresponds to a temperature of the thermalized system being systematically lower than the value determined by the yields of the stable and long-lived hadrons produced in Ar + KCl collisions. From the present measurement, we conclude that sub-threshold K* production either cannot be considered to proceed in a system being in thermal equilibrium or these short-lived resonances appear undersaturated, for example as a result of the rescattering of the decay particles in the ambient hadronic medium. |
| Address |
Inst Nazl Fis Nucl, Lab Nazl Sud, I-95125 Catania, Italy, Email: kotte@hzdr.de |
| Corporate Author |
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Thesis |
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| Publisher |
Springer |
Place of Publication |
|
Editor |
|
| 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 |
|
| ISSN |
1434-6001 |
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:000317855000006 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1426 |
| Permanent link to this record |
