Magdalena Skurzok
In this paper the search for eta-mesic nuclei with particular focus on light $η$-He bound states is reviewed. A brief description of recent theoretical studies and experimental results is presented.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
继续探索
We review status and perspectives of the search of the eta-mesic helium at the cooler synchrotron COSY.
We performed a search for 4He-eta bound state with high statistics and high acceptance with the WASA-at-COSY facility using a ramped beam technique. The signature of eta-mesic nuclei is searched for in dd -> 3Henpi0 and dd -> 3Heppi- reactions by the measurement of the excitation functions in the vicinity of the η production threshold. This paper presents the experimental method and the preliminary results of the data analysis for dd -> 3Henpi0 process.
In this report the search for eta-mesic nuclei is reviewed. The brief description of the experimental studies is presented with a focus on the possible production of the eta-nucleus bound states for light nuclei like 4He and 3He.
The eta-mesic nuclei in which the eta meson is bound with nucleus via strong interaction was postulated already in 1986, however till now no experiment confirmed empirically its existence. The discovery of this new kind of an exotic nuclear matter would be very important for better understanding of the eta meson structure and its interaction with nucleons. The search for eta-mesic helium is carried out with high statistic and high acceptance with the WASA-at-COSY detection setup in the Forschungszentrum Julich. The search is conducted via the measurement of the excitation function for the chos…
Short history of ideas concerning a possible existence of bound states of the $η$-meson and a nucleus is considered. First experiments at BNL and LAMPF on searching for these states are discussed. Another recent experiment using the photon beam of the 1 GeV electron synchrotron of LPI is described. Possible experiments on studying $η$-mesic nuclei using a proton beam (at Nuclotron of Dubna) and a $γ$-beam (CEBAF, JLAB) are suggested.
We conduct a search for the 4He-eta bound state with the WASA-at-COSY facility via the measurement of the excitation function for the reaction dd->3Heppi-. In first experiment performed in June 2008, we used COSY deuteron beam with a slowly ramped beam momentum corresponding to a variation of the excess energy for the 4He-eta system from -51.4 MeV to 22 MeV. Here we report on the status of the measurement and the data evaluation.
The eta-mesic nuclei in which the eta meson is bound with nucleus via strong interaction was postulated about 25 years ago, however till now no experiment confirmed empirically its existence. The discovery of this new kind of an exotic nuclear matter would be very important for better understanding of the eta meson structure and its interaction with nucleons. The search for eta-mesic helium is carried out with high statistic and high acceptance with the WASA-at-COSY detection setup and the Cooler Synchrotron COSY. The search is conducted via the measurement of the excitation function for the c…
We performed a search for 4He-eta bound state in dd -> 3Henpi0 and dd -> 3Heppi- reactions with the WASA-at-COSY facility using a ramped beam technique. The measurement was carried out with high statistics and high acceptance. The signature of eta-mesic nuclei was searched for by the measurement of the excitation functions in the vicinity of the eta production threshold for each of the considered channels. We did not observe the narrow structure which could be interpreted as a bound state. The preliminary upper limits of the total cross sections for the bound state production and decay varies …
A search for the 4He-eta bound state via exclusive measurement of the excitation function for the dd->3Heppi- reaction, was performed at the Cooler Synchrotron COSY-Juelich with the WASA-at-COSY detection system. The data were taken during a slow acceleration of the beam from 2.185 GeV/c to 2.400 GeV/c crossing the kinematic threshold for the eta production in the dd -> 4He-eta reaction at 2.336 GeV/c. The corresponding excess energy in the 4He-eta system varied from -51.4 MeV to 22 MeV. The shape of the excitation function for the dd -> 3Heppi- was examined. No signal of the 4He-eta bound sta…
In November 2010, we performed a search for a $^{4}\mbox{He}$-$η$ bound state by measuring the excitation function for the $dd\rightarrow$ $^{3}\mbox{He} n π^{0}$ and $dd\rightarrow$ $^{3}\mbox{He} p π^{-}$ reactions in the vicinity of the $η$ production threshold with the WASA detector.~The experiment was carried out using a deuteron COSY beam and deuteron pellet target. The beam momentum varied continuously in each of acceleration cycle from 2.127 GeV/c to 2.422 GeV/c, which corresponds to a range of excess energy $Q$ $\in$(-70,30)MeV. This dissertation is about the search for $^{4}\mbox{He}…
We search for an evidence of eta-mesic He with the WASA detector. Two dedicated experiments were performed at the Cooler Synchrotron COSY-Juelich. The experimental method is based on the measurement of the excitation functions for the two reaction channels: dd->3Heppi- and dd->3Henpi0, where the outgoing N-pi pairs originate from the conversion of the eta meson on a nucleon inside the He nucleus.In this contribution, the experimental method is shortly described and the current status of the analysis is presented.
Despite the fact that existence of η-mesic nuclei in which the η meson might be bound with the light nucleus by means of the strong interaction was postulated already in 1986, it is still not experimentally confirmed. Discovering of this new kind of an exotic nuclear matter is very important as it might allow for better understanding of η meson structure and its interaction with nucleons. The search of the η-helium bound states is carried out at the COSY accelerator in the Research Center Juelich in Germany, by means of the WASA detection system. The search are conducted with high statistic an…
The isoscalar $η$ and $η'$ mesons are special in QCD, being linked both to chiral symmetry and to non-perturbative glue associated with the axial anomaly. The properties of these mesons in medium are sensitive to how these dynamics work in the nuclear environment. In contrast to pionic and kaonic atoms which are mainly bound by the Coulomb interaction with some corrections due to the strong force (Coulomb assisted binding), the $η$ and $η'$ as neutral mesons can only be bound by the strong interaction. Is this interaction strong enough? This topic has inspired a vigorous program of experiments…
The excitation function for the $pd\rightarrow$ $d p π^{0}$ reaction has been measured by WASA-at-COSY experiment with the aim of searching for $^{3}\hspace{-0.03cm}\mbox{He}$-$η$ mesic nuclei. The measurement in the vicinity of $η$ meson production was performed using a ramped proton beam. The data analysis and interpretation was carried out with the assumption that the $η$-mesic Helium decays via the formation of an intermediate N$^{*}$(1535) resonance. No direct signal of the $η$-mesic nucleus is observed in the excitation function. We determine a new improved upper limit for the total cros…
We report on the status of the search for eta-mesic nuclei and the studies of the interaction of the eta meson with nucleons. Recently we have completed the analysis of the new WASA-at-COSY data on the production of the eta meson with polarized proton beam. New results on the analyzing power for the pp->ppeta reaction with more than an order of magnitude improved precision shed a new light on the production mechanism of the eta meson in nucleon-nucleon collisions. Also, the latest results of the search for eta-mesic nuclei are discussed.
The eta-mesic nuclei in which the η meson is bound with nucleus via strong interaction was postulated already in 1986, however till now no experiment confirmed empirically its existence. The discovery of this new kind of an exotic nuclear matter would be very important for better understanding of the η meson structure and its interaction with nucleons. The search for η-mesic helium is carried out with high statistic and high acceptance with the WASA-at-COSY detection setup in the Research Center Juelich. The search is conducted via the measurement of the excitation function for the chosen deca…
The existence of eta-mesic nuclei in which the eta meson is bound in a nucleus by means of the strong interaction was postulated already in 1986, albeit not yet confirmed it by experiment. The discovery of this new kind of an exotic nuclear matter would be very important as it might allow for a better understanding of the eta meson structure and its interaction with nucleons. The search for eta-mesic helium 4He-eta is carried out with high statistics and high acceptance with the WASA detector, installed at the cooler synchrotron COSY of the Research Center Juelich. The search is conducted via …
In November 2010, the search for the 4He-η bound state was per formed with high statistics and high acceptance with the WASA-at-COSY facility using a ramped beam technique. The signature of eta - mesic nuclei is searched for in the measured excitation functions for the two reaction channels: dd ->3He n pi0 and dd ->3He p pi- near the eta production threshold. This report includes the description of the experimental method and the status of the data analysis.
扫码添加微信好友，提出您的宝贵建议 👇
💡 备注请填写：网站反馈
发表机构由 AI 从论文文本抽取，如发现错误，欢迎反馈修正建议。