| 1. |
- Yamaga, Takumi, et al.
(författare)
-
Study of the elementary (K -, n) reactions to search for the K NN bound state via the 3He (K -, n) reaction at J-PARC
- 2016
-
Ingår i: XVIth International Conference on Hadron Spectroscopy, Hadron 2015. - : Author(s). - 9780735413894 ; 1735
-
Konferensbidrag (refereegranskat)abstract
- We have searched for the simplest kaonic nuclear state, K̄NN, using the in-flight 3He (K-, n) reaction at the J-PARC hadron experimental facility. In the semi-inclusive neutron missing-mass spectrum at θnlab=0°, an excess of yield was observed just below the K- pp mass-threshold, which cannot be explained by any elementary reactions [PTEP 2015, 061D01]. To understand the missing-mass spectrum of 3He (K-, n) X, we investigated the elementary (K-, n) reactions using hydrogen and deuterium targets. The p (K-, n) X missing-mass spectrum was well described by the charge-exchange reaction. However, in the d (K-, n) X spectrum, we observed an excess of yield just below the K- p mass-threshold, which was similar to that in the 3He (K-, n) X spectrum.
|
|
| 2. |
- Asano, H., et al.
(författare)
-
Spectroscopic study of the Λ(1405) resonance via the d (K-, n) reaction at J-PARC
- 2019
-
Ingår i: 13th International Conference on Hypernuclear and Strange Particle Physics, HYP 2018. - : AIP Publishing. - 9780735418721 ; 2130
-
Konferensbidrag (refereegranskat)abstract
- The structure of the Λ(1405) hyperon is an important and long-standing issue related to the K̄-nucleus interaction. The J-PARC E31 experiment has been performed to investigate the Λ(1405) spectrum shape. Because it is hard to form the Λ(1405) directly by a K̄N scattering in free space, E31 uses the d(K-, n) reaction with an incident kaon momentum of 1 GeV/c. We will identify three final states - ς-π+, ς+π-, ς0π0-so that the isospin structure of hyperon resonance states produced can be decomposed. The first physics run of the E31 experiment was performed in 2016. To enhance the statistics of the data set, we have performed the second physics run in the beginning of 2018. During the second run of E31, around 3.9×1010 kaons impacted on the deuteron target.
|
|
| 3. |
- Sada, Y., et al.
(författare)
-
Structure near the K- + p + p threshold in the in-flight 3He(K-, Λp)n reaction
- 2016
-
Ingår i: Progress of Theoretical and Experimental Physics. - : Oxford University Press (OUP). - 2050-3911. ; 2016:5
-
Tidskriftsartikel (refereegranskat)abstract
- To search for an S = -1 di-baryonic state which decays toΛp, the 3He(K-,Λp)nmissing reaction was studied at 1.0 GeV/c. Unobserved neutrons were kinematically identified from the missing mass MX of the 3He (K-,Λp) X reaction in order to have a large acceptance for the Λpn final state. The observed Λpn events, distributed widely over the kinematically allowed region of the Dalitz plot, establish that the major component comes from a three-nucleon absorption process. A concentration of events at a specific neutron kinetic energy was observed in a region of low momentum transfer to the Λp. To account for the observed peak structure, the simplest S-wave polewas assumed to exist in the reaction channel, having a Breit-Wigner formin energy and with a Gaussian form factor. A minimum X2 method was applied to deduce its mass, MX = 2355+6 -8 (stat.) ±12 (syst.)MeV/c2, and decay width, γX = 110+19 -17 (stat.) ±27 (syst.)MeV/c2, respectively. The form factor parameter QX ∼ 400MeV/c implies that the range of the interaction is about 0.5 fm.
|
|
| 4. |
- Hashimoto, T., et al.
(författare)
-
Beamline test of a transition-edge-sensor spectrometer in preparation for kaonic-atom measurements
- 2017
-
Ingår i: IEEE Transactions on Applied Superconductivity. - 1051-8223. ; 27:4
-
Tidskriftsartikel (refereegranskat)abstract
- We are developing a new technique to apply transition-edge sensors (TESs) to X-ray spectroscopy of exotic atoms, especially of kaonic atoms. To demonstrate the feasibility of this pioneering project, performance of a TES-based X-ray detector was evaluated in pion- and kaon-beam environments at particle accelerators.We successfully observed X-rays from pionic-carbon atoms with a resolution as good as 7 eV FWHM at 6 keV. Also at a kaon beamline, we confirmed that the TES spectrometer will be able to achieve our resolution goal, 6 eV, in our first scientific campaign to measure X-rays from kaonic-helium atoms.
|
|
| 5. |
- Hashimoto, T., et al.
(författare)
-
Kaonic-Atom X-ray Spectroscopy with Superconducting Microcalorimeters
- 2017
-
Ingår i: Proceedings of the 12th International Conference on Hypernuclear and Strange Particle Physics (HYP2015). - 9784890271221 ; 17
-
Konferensbidrag (refereegranskat)abstract
- We will measure kaonic helium X-rays using transition-edge-sensor microcalorimeters, TES, in the J-PARC hadron experimental facility. To demonstrate the feasibility of the experiment, we performed a measurement of pionic carbon X-rays at PSI, where an excellent FWHM energy resolution of 7 eV at 6.4 keV was achieved. We also evaluated the expected TES performance in the kaon beam at J-PARC. The simulation results show that the TES spectrometer would work with a good energy resolution, and clear peaks of kaonic helium X-rays would be observed on a reasonably suppressed background.
|
|
| 6. |
- Curceanu, C., et al.
(författare)
-
Kaonic deuterium measurement with Siddharta-2 on daΦNE
- 2020
-
Ingår i: Acta Physica Polonica B. - 0587-4254. ; 51:1, s. 251-257
-
Tidskriftsartikel (refereegranskat)abstract
- The interaction of antikaons with nucleons and nuclei in the low-energy regime represents an active research field in hadron physics with still many important open questions. The investigation of light kaonic atoms is, in this context, a unique tool to obtain precise information on this interaction. The most precise kaonic hydrogen measurement to date, together with an exploratory measurement of kaonic deuterium, were carried out by the SIDDHARTA Collaboration at the DAΦNE electron–positron collider of LNF-INFN, by combining the excellent quality kaon beam delivered by the collider with new experimental techniques, as fast and precise Silicon-Drift X-ray detectors. The measurement of kaonic deuterium will be realized in the near future by SIDDHARTA-2, a major upgrade of SIDDHARTA.
|
|
| 7. |
- Curceanu, C., et al.
(författare)
-
Low-energy kaon-nuclei interaction studies at DAΦNE : Siddharta-2 and amadeus
- 2017
-
Ingår i: Acta Physica Polonica B. - 0587-4254. ; 48:10, s. 1855-1860
-
Tidskriftsartikel (refereegranskat)abstract
- The DAΦNE electron-positron collider of the Laboratori Nazionali di Frascati of INFN has made available a unique quality low-energy negatively charged kaons "beam", which is being used to study the kaon-nucleon/nuclei interactions by the SIDDHARTA-2 experiment and the AMADEUS Collaboration. The dynamics of the strong interaction processes in the nonperturbative regime is approached by lattice calculations and effective field theories (ChPT) which are still lacking experimental results in the lowenergy regime, fundamental for their good understanding. The studies of kaonic atoms and of the kaonic nuclear processes performed by SIDDHARTA- 2 and AMADEUS play in this context a key-role.
|
|
| 8. |
- Curceanu, C., et al.
(författare)
-
The kaonic atoms research program at DAΦNE : Overview and perspectives
- 2018
-
Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 1138:1
-
Tidskriftsartikel (refereegranskat)abstract
- The interaction of antikaons with nucleons and nuclei in the low-energy regime represents an active research field in hadron physics with still many important open questions. The investigation of light kaonic atoms is, in this context, a unique tool to obtain precise information on this interaction. The energy shift and broadening of the lowest-lying states of such atoms, induced by the kaon-nucleus strong interaction, can be determined with high precision from atomic X-ray spectroscopy. This experimental method provides unique information to understand the low energy kaon-nucleus interaction at threshold. The lightest atomic systems, kaonic hydrogen and kaonic deuterium, deliver the isospin-dependent kaon-nucleon scattering lengths. The most precise kaonic hydrogen measurement to date, together with an exploratory measurement of kaonic deuterium, were carried out by the SIDDHARTA collaboration at the DAΦNE electron-positron collider of LNF-INFN, by combining the excellent quality kaon beam delivered by the collider with new experimental techniques, as fast and precise X-ray detectors: Silicon Drift Detectors. The measurement of kaonic deuterium will be realized in the near future by SIDDHARTA-2, a major upgrade of SIDDHARTA. In this paper an overview of the main results obtained by SIDDHARTA together with the future plans, are given.
|
|
| 9. |
- De Paolis, L., et al.
(författare)
-
Kaonic atoms measurement at DA Φ NE : SIDDHARTA and SIDDHARTA-2
- 2019
-
Ingår i: Basic Concepts in Nuclear Physics : Theory, Experiments and Applications - 2018 La Rábida International Scientific Meeting on Nuclear Physics - Theory, Experiments and Applications - 2018 La Rábida International Scientific Meeting on Nuclear Physics. - Cham : Springer International Publishing. - 9783030222031 ; 225, s. 191-195
-
Konferensbidrag (refereegranskat)abstract
- Light kaonic atoms studies provide the unique opportunity to perform experiments equivalent to scattering at threshold, being their atomic binding energies in the keV range. High precision atomic X-rays spectroscopy ensures that the energy shift and broadening of the lowest-lying states of the kaonic atoms, induced by the strong interaction between the kaon and nucleus, can be detected. Kaonic hydrogen and kaonic deuterium are the lightest atomic systems and their study deliver the isospin-dependent kaon-nucleon scattering lengths. The SIDDHARTA collaboration was able to perform the most precise kaonic hydrogen measurement to date, together with an exploratory measurement of kaonic deuterium. The measurement of the kaonic deuterium will be realized in the near future by a major upgrade of SIDDHARTA: SIDDHARTA-2. In this paper an overview of the main results obtained by SIDDHARTA together with the future plans are presented.
|
|
| 10. |
- Marton, J., et al.
(författare)
-
Spectroscopy of kaonic atoms at DAFNE and J-PARC
- 2019
-
Ingår i: Proceedings - 15th International Workshop on Meson Physics, MESON 2018. - : EDP Sciences.
-
Konferensbidrag (refereegranskat)abstract
- The interaction of antikaons (K) with nucleons and nuclei in the low-energy regime represents a very active research field in hadron physics. A unique and rather direct experimental access to the antikaon-nucleon scattering lengths is provided by precision X-ray spectroscopy of transitions in low-lying states in the lightest kaonic atoms (i.e. kaonic hydrogen and deuterium). In the SIDDHARTA experiment at the electron-positron collider DAFNE of LNFINFN we measured the most precise values of the strong interaction observables in conic hydrogen. The strong interaction on the 1s ground state of the electromagnetically bound K-p atom causes an energy shift and broadening of the 1s state. SIDDHARTA will extend the spectroscopy to kaonic deuterium to get access to the antikaon-neutron interaction and thus the isospin dependent scattering lengths. At J-PARC a kaon beam is used in a complementary experiment with a different setup for spectroscopy of kaonic deuterium atoms. The talk will give an overview of the of the upcoming experiments SIDDHARTA and the complementary experiment at J-PARC.Furthermore, the implications of the experiments for the theory of low-energy strong interaction with strangeness will be discussed.
|
|
