Search

Your search keyword '"Cabanelas P"' showing total 616 results
Start Over Author "Cabanelas P"
616 results on '"Cabanelas P"'

1. Study of (p,2p) fission reactions in inverse kinematics using the R3B set-up

Author

García-Jiménez G., Alvarez-Pol H., Graña-González A., Rodríguez-Sánchez J.L., Benlliure J., Cortina-Gil D., Atar L., Audouin L., Authelet G., Besteiro A., Blanchon G., Boretzky K., Borge M.J.G., Cabanelas P., Casarejos E., Cederkall J., Chatillon A., Corsi A., Feijoo M., De Filippo E., Galaviz D., Gasparic I., Geraci E., Gernhäuser R., Gnoffo B., Heil M., Heinz A., Hensel T., Holl M., Jelavic Malenica D., Jenegger T., Ji L., Johansson H.T., Kiselev O.A., Klenze P., Knyazev A., Körper D., Kröll T., Lithar I., Litvinov Y.A., Löher B., Martorana N. S., Morfouace P., Mücher D., Murillo-Morales S., Obertelli A., Panin V., Park J., Paschalis S., Perea A., Petri M., Pirrone S., Ponnath L., Revel A., Rhee H., Rose L., Rossi D.M., Russotto P., Simon H., Stott A., Sun Y., Sürder C., Taïeb J., Taniuchi R., Tengblad O., Törnqvist H.T., Trimarchi M., Velardita S., Vesic J., and Voss B.

Subjects
Physics, QC1-999
Abstract

A new experimental fission approach is presented in the context of the R3B (Reactions with Relativistic Radioactive Beams) collaboration, at the GSI/FAIR facility, in which knockout reactions in inverse kinematics are used to induce fission of 238U that will allow to characterise the excitation energy of the fission process and all the fission products. The CALIFA (CALorimeter for In-Flight detection of γ-rays and high energy charged pArticles) calorimeter, a key part of the R3B set-up, is used to reconstruct the momenta of the two protons from the (p, 2p) reactions. Preliminary results show that kinematic variables and first estimates for nucleon-removal cross sections are well reconstructed and in good agreement with other experimental measurements.

Published
2023
Full Text
View/download PDF

2. Fission studies in inverse kinematics with the R3B setup

Author

Graña-González A., Rodríguez-Sánchez J.L., Benlliure J., García-Jiménez G., Alvarez-Pol H., Cortina-Gil D., Atar L., Audouin L., Authelet G., Besteiro A., Blanchon G., Boretzky K., Borge M.J.G., Cabanelas P., Casarejos E., Cederkall J., Chatillon A., Corsi A., Feijoo M., De Filippo E., Galaviz D., Gasparic I., Geraci E., Gernhäuser R., Gnoffo B., Heil M., Heinz A., Hensel T., Holl M., Jelavic Malenica D., Jenegger T., Ji L., Johansson H., Kiselev O.A., Klenze P., Knyazev A., Körper D., Kröll T., Lihtar I., Litvinov Y., Löher B., Martorana N.S., Morfouace P., Mücher D., Murillo Morales S., Obertelli A., Panin V., Park J., Paschalis S., Perea A., Petri M., Pirrone S., Ponnath L., Revel A., Rhee H.-B., Rose L., Rossi D.M., Russotto P., Simon H., Stott A., Sun Y., Sürder C., Taïeb J., Taniuchi R., Tengblad O., Törnqvist H.T., Trimarchi M., Velardita S., Vesic J., and Voss B.

Subjects
Physics, QC1-999
Abstract

Nuclear fission is a complex dynamical process, whose description involves the coupling between intrinsic and collective degrees of freedom, as well as different quantum-mechanical phenomena. For this reason, to this day it still lacks a satisfactory and complete microscopic description. In addition to the importance of describing fission itself, studies of the r-process in astrophysics depend on fission observables to constrain the theoretical models that explain the isotopic abundances in the Universe. To improve on the existing data, fission reactions of heavy nuclei in inverse kinematics are produced in quasi-free (p,2p) scattering reactions, which induce fission through particle-hole excitations that can range from few to tens of MeV. In order to study the evolution of the fission yields with temperature, the excitation energy of the fissioning system must be reconstructed, which is possible by measuring the four-momenta of the two outgoing protons. Performing this kind of experiment requires a complex experimental setup, providing full isotopic identification of both fission fragments and an accurate measurement of the momenta of the two outgoing protons. This was realized recently at the GSI/FAIR facility and some of the results obtained for the charge distributions are presented in this work.

Published
2023
Full Text
View/download PDF

4. High-resolution evaluation of the U5(n,f) cross section from 3 keV to 30 keV

Author

Duran I., Paradela C., Caamaño M., Cabanelas P., Tassan-Got L., and Audouin L.

Subjects
Physics, QC1-999
Abstract

235U neutron-induced fission cross-section is commonly used as reference for determining other isotope fission cross-section. However, below 150 keV this cross section is only included as Standard at the thermal point and recently its integral value between 7.8 eV and 11 eV [1]. The resolved resonance region, spanning up to 2.25 keV, has been reevaluated with high resolution in the last ENDF/B-VIII release [2] and a SAMMY resonance analysis was done by L. Leal et al. [3] including the CERN-nTOF experimental work of Paradela el al. [4] up to 10 keV, taken into account the IAEA Reference file. In this work the 235U(n,f) low-background and high-resolution experimental data obtained at the CERN-nTOF facility is combined with previous high-resolution experimental data, in order to produce a very fine grid dataset with normalisation to the IAEA Reference file. The extremelyhigh energy calibration required to reproduce the resonance sharp profiles is based on the nTOF DAQ system with a resolution below 0.1% with reference to the 8.78 eV resonance and to the sharp Al(n,g) capture dip at 5.904 keV. The comparison of the so-evaluated profile with the experimental data and with the evaluated ones will be discussed.

Published
2019
Full Text
View/download PDF

5. Quasi-free (p,2p) reactions in inverse kinematics for studying the fission yield dependence on temperature

Author

Graña-González, A., Rodríguez-Sánchez, J. L., Benlliure, J., García-Jiménez, G., Alvarez-Pol, H., Cortina-Gil, D., Atar, L., Audouin, L., Authelet, G., Besteiro, A., Blanchon, G., Boretzky, K., Cabanelas, P., Casarejos, E., Cederkall, J., Chatillon, A., Corsi, A., Feijoo, M., Galaviz, D., Gasparic, I., Gernhäuser, R., Heil, M., Heinz, A., Holl, M., Jenegger, T., Ji, L., Johansson, H. T., Kiselev, O. A., Klenze, P., Knyazev, A., Körper, D., Kröll, T., Lihtar, I., Litvinov, Y. A., Löher, B., Morfouace, P., Mücher, D., Murillo-Morales, S., Obertelli, A., Panin, V., Park, J., Paschalis, S., Perea, A., Petri, M., Pirrone, S., Ponnath, L., Revel, A., Rhee, H. B., Rose, L., Rossi, D. M., Russotto, P., Simon, H., Stott, A., Sun, Y., Sürder, C., Taïeb, J., Taniuchi, R., Tengblad, O., Törnqvist, H. T., Velardita, S., Vesic, J., and Voss, B.

Subjects
Nuclear Experiment
Abstract

Despite the recent experimental and theoretical progress in the investigation of the nuclear fission process, a complete description still represents a challenge in nuclear physics because it is a very complex dynamical process, whose description involves the coupling between intrinsic and collective degrees of freedom, as well as different quantum-mechanical phenomena. To improve on the existing data on nuclear fission, we produce fission reactions of heavy nuclei in inverse kinematics by using quasi-free (p,2p) scattering, which induce fission through particle-hole excitations that can range from few to ten's of MeV. The measurement of the four-momenta of the two outgoing protons allows to reconstruct the excitation energy of the fissioning compound nucleus and therefore to study the evolution of the fission yields with temperature. The realization of this kind of experiment requires a complex experimental setup, providing full isotopic identification of both fission fragments and an accurate measurement of the momenta of the two outgoing protons. This was realized recently at the GSI/FAIR facility and here some preliminary results are presented., Comment: 6 pages, 2 figures, FAIRNESS 2022. arXiv admin note: text overlap with arXiv:2210.04741

Published
2022

6. Comprehensive investigation of fission yields by using spallation- and (p,2p)-induced fission reactions in inverse kinematics

Author

Rodríguez-Sánchez, J. L., Graña-González, A., Benlliure, J., Chatillon, A., García-Jiménez, G., Taieb, J., Alvarez-Pol, H., Atar, L., Audouin, L., Authelet, G., Besteiro, A., Blanchon, G., Boretzky, K., Cabanelas, P., Casarejos, E., Cederkall, J., Cortina-Gil, D., Corsi, A., De Filippo, E., Feijoo, M., Galaviz, D., Gasparic, I., Gernhäuser, R., Haettner, E., Heil, M., Heinz, A., Holl, M., Jenegger, T., Ji, L., Johansson, H. T., Kelić-Heil, A., Kiselev, O. A., Klenze, P., Knyazev, A., Körper, D., Kröll, T., Lihtar, I., Litvinov, Y. A., Löher, B., Martorana, N., Morfouace, P., Mücher, D., Morales, S. Murillo, Obertelli, A., Panin, V., Park, J., Paschalis, S., Perea, A., Petri1, M., Pietri, S., Pirrone, S., Ponnath, L., Revel, A., Rhee, H. -B., Rose, L., Ross, D. M., Russotto, P., Simon, H., Stott, A., Sun, Y., Sürder, C., Taniuchi, R., Tengblad, O., Törnqvist, H. T., Trimarchi, M., Velardita, S., Vesic, J., Voss, B., and Weick, H.

Subjects
Nuclear Experiment
Abstract

In the last decades, measurements of spallation, fragmentation and Coulex induced fission reactions in inverse kinematics have provided valuable data to accurately investigate the fission dynamics and nuclear structure at large deformations of a large variety of stable and non-stable heavy nuclei. To go a step further, we propose now to induce fission by the use of quasi-free (p,2p) scattering reactions in inverse kinematics, which allows us to reconstruct the excitation energy of the compound fissioning system by using the four-momenta of the two outgoing protons. Therefore, this new approach might permit to correlate the excitation energy with the charge and mass distributions of the fission fragments and with the fission probabilities, given for the first time direct access to the simultaneous measurement of the fission yield dependence on temperature and fission barrier heights of exotic heavy nuclei, respectively. The first experiment based on this methodology was realized recently at the GSI/FAIR facility and a detailed description of the experimental setup is given here., Comment: 4 pages, 15th International Conference on Nuclear Data for Science and Technology (ND2022)

Published
2022
Full Text
View/download PDF

7. Low mass dielectrons radiated off cold nuclear matter measured with HADES

Author

Lorenz M., Agakishiev G., Behnke C., Belver D., Belyaev A., Berger-Chen J.C., Blanco A., Blume C., Böhmer M., Cabanelas P., Chernenko S., Dritsa C., Dybczak A., Epple E., Fabbietti L., Fateev O., Fonte P., Friese J., Fröhlich I., Galatyuk T., Garzón J. A., Gill K., Golubeva M., González-Díaz D., Guber F., Gumberidze M., Harabasz S., Hennino T., Höhne C., Holzmann R., Huck P., Ierusalimov A., Ivashkin A., Jurkovic M., Kämpfer B., Karavicheva T., Koenig I., Koenig W., Kolb B. W., Korcyl G., Kornakov G., Kotte R., Krása A., Krebs E., Krizek F., Kuc H., Kugler A., Kurepin A., Kurilkin A., Kurilkin P., Ladygin V., Lalik R., Lang S., Lapidus K., Lebedev A., Lopes L., Maier L., Mangiarotti A., Markert J., Metag V., Michel J., Müntz C., Münzer R., Naumann L., Palka M., Parpottas Y., Pechenov V., Pechenova O., Pietraszko J., Przygoda W., Ramstein B., Rehnisch L., Reshetin A., Rustamov A., Sadovsky A., Salabura P., Scheib T., Schuldes H., Siebenson J., Sobolev Yu.G., Spataro S., Ströbele H., Stroth J., Strzempek P, Sturm C., Svoboda O., Tarantola A., Teilab K., Tlusty P., Traxler M., Tsertos H., Vasiliev T., Wagner V., Weber M., Wendisch C., Wüstenfeld J., Yurevich S., and Zanevsky Y.

Subjects
Physics, QC1-999
Abstract

The High Acceptance DiElectron Spectrometer HADES [1] is installed at the Helmholtzzentrum für Schwerionenforschung (GSI) accelerator facility in Darmstadt. It investigates dielectron emission and strangeness production in the 1-3 AGeV regime. A recent experiment series focusses on medium-modifications of light vector mesons in cold nuclear matter. In two runs, p+p and p+Nb reactions were investigated at 3.5 GeV beam energy; about 9·109 events have been registered. In contrast to other experiments the high acceptance of the HADES allows for a detailed analysis of electron pairs with low momenta relative to nuclear matter, where modifications of the spectral functions of vector mesons are predicted to be most prominent. Comparing these low momentum electron pairs to the reference measurement in the elementary p+p reaction, we find in fact a strong modification of the spectral distribution in the whole vector meson region.

Published
2014
Full Text
View/download PDF

8. In-medium hadron properties measured with HADES

Author

Pietraszko J., Agakishiev G., Behnke C., Belver D., Belyaev A., Berger-Chen J.C., Blanco A., Blume C., Böhmer M., Cabanelas P., Chernenko S., Dritsa C., Dybczak A., Epple E., Fabbietti L., Fateev O., Fonte P., Friese J., Fröhlich I., Galatyuk T., Garzón J. A., Gill K., Golubeva M., González-Díaz D., Guber F., Gumberidze M., Harabasz S., Hennino T., Höhne C., Holzmann R., Huck P., Ierusalimov A., Ivashkin A., Jurkovic M., Kämpfer B., Karavicheva T., Koenig I., Koenig W., Kolb B. W., Korcyl G., Kornakov G., Kotte R., Krása A., Krebs E., Krizek F., Kuc H., Kugler A., Kurepin A., Kurilkin A., Kurilkin P., Ladygin V., Lalik R., Lang S., Lapidus K., Lebedev A., Lopes L., Lorenz M., Maier L., Mangiarotti A., Markert J., Metag V., Michel J., Müntz C., Münzer R., Naumann L., Palka M., Parpottas Y., Pechenov V., Pechenova O., Przygoda W., Ramstein B., Rehnisch L., Reshetin A., Rustamov A., Sadovsky A., Salabura P., Scheib T., Schuldes H., Siebenson J., Sobolev Yu.G., Spataro S., Ströbele H., Stroth J., Strzempek P, Sturm C., Svoboda O., Tarantola A., Teilab K., Tlusty P., Traxler M., Tsertos H., Vasiliev T., Wagner V., Weber M., Wendisch C., Wüstenfeld J., Yurevich S., and Zanevsky Y.

Subjects
Physics, QC1-999
Abstract

Many QCD based and phenomenological models predict changes of hadron properties in a strongly interacting environment. The results of these models differ significantly and the experimental determination of hadron properties in nuclear matter is essential. In this paper we present a review of selected physics results obtained at GSI Helmholtzzentrum für Schwerionenforschung GmbH by HADES (High-Acceptance Di-Electron Spectrometer). The e+e− pair emission measured for proton and heavy-ion induced collisions is reported together with results on strangeness production. The future HADES activities at the planned FAIR facility are also discussed.

Published
2014
Full Text
View/download PDF

11. Commissioning of the CALIFA Barrel Calorimeter of the R$^{3}$B Experiment at FAIR

Author

Cabanelas, P, Alvarez-Pol, H, Boillos, J M, Casarejos, E, Cederkall, J, Cortina, D, Feijoo, M, Galaviz, D, Gernhäuser, E Galiana R, Golubev, P, González, D, Hartig, A-L, Heinz, A, Johansson, H, Klenze, P, Knyazev, A, Kröll, T, Nacher, E, Park, J, Perea, A, Ponnath, L, Rhee, H-B, Rodríguez-Sánchez, J L, Suerder, C, Tengblad, O, and Teubig, P

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract

CALIFA is the high efficiency and energy resolution calorimeter for the R$^{3}$B experiment at FAIR, intended for detecting high energy charged particles and $\gamma$-rays in inverse kinematics direct reactions. It surrounds the reaction target in a segmented configuration of Barrel and Forward End-Cap pieces. The CALIFA Barrel consists of 1952 detection units made of CsI(Tl) long-shaped scintillator crystals, and it is being commissioned during the Phase0 experiments at FAIR. The first setup for the CALIFA Barrel commissioning is presented here. Results of detector performance with $\gamma$-rays are obtained, and show that the system fulfills the design requirements.

Published
2020
Full Text
View/download PDF

12. Performance recovery of long CsI(Tl) scintillator crystals with APD-based readout

Author

Cabanelas, P., González, D., Alvarez-Pol, H., Boillos, J. M., Casarejos, E., Cederkall, J., Cortina, D., Feijoo, M., Galaviz, D., Galiana, E., Gernhäuser, R., Golubev, P., Hartig, A. -L., Klenze, P., Knyazev, A., Kröll, T., Nácher, E., Park, J., Perea, A., Pietras, B., Ponnath, L., Rhee, H. -B., Rodríguez-Sánchez, J. L., Suerder, C., Tengblad, O., and Teubig, P.

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract

CALIFA is the high efficiency and energy resolution calorimeter for the R3B experiment at FAIR, intended for detecting high energy light charged particles and gamma rays in scattering experiments, and is being commissioned during the Phase-0 experiments at FAIR, between 2018 and 2020. It surrounds the reaction target in a segmented configuration with 2432 detection units made of long CsI(Tl) finger-shaped scintillator crystals. CALIFA has a 10 year intended operational lifetime as the R3B calorimeter, necessitating measures to be taken to ensure enduring performance. In this paper we present a systematic study of two groups of 6 different detection units of the CALIFA detector after more than four years of operation. The energy resolution and light output yield are evaluated under different conditions. Tests cover the aging of the first detector units assembled and investigates recovery procedures for degraded detection units. A possible reason for the observed degradation is given, pointing to the crystal-APD coupling.

Published
2020
Full Text
View/download PDF

13. The dp-elastic cross section measurement at the deuteron kinetic energy of 2.5 GeV

Author

Rustamov A., Reshetin A., Rehnisch L., Ramstein B., Przygoda W., Pietraszko J., Pechenova O., Parpottas Y., Pechenov V., Palka M., Naumann L., Münzer R., Müntz C., Michel J., Metag V., Markert J., Mangiarotti A., Maier L., Lorenz M., Lopes L., Lebedev A., Lapidus K., Lang S., Lalik R., Ladygin V., Kurilkin A., Kurepin A., Kuc H., Kugler A., Krizek F., Krebs E., Krása A., Kotte R., Kornakov G., Korcyl G., Kolb B. W., Koenig W., Koenig I., Kämpfer B., Karavicheva T., Jurkovic M., Ivashkin A., Ierusalimov A., Höhne C., Huck P., Holzmann R., Hennino T., Harabasz S., Gumberidze M., Guber F., González-Díaz D., Golubeva M., Gill K., Galatyuk T., Garzón J. A., Fröhlich I., Fonte P., Friese J., Fateev O., Fabbietti L., Epple E., Dybczak A., Dritsa C., Chernenko S., Cabanelas P., Böhmer M., Blume C., Blanco A., Berger-Chen J.C., Belyaev A., Belver D., Behnke C., Agakishiev G., Kurilkin P., Sadovsky A., Salabura P., Scheib T., Schuldes H., Siebenson J., Sobolev Yu.G., Spataro S., Ströbele H., Stroth J., Strzempek P., Sturm C., Svoboda O., Tarantola A., Teilab K., Tlusty P., Traxler M., Tsertos H., Vasiliev T., Wagner V., Weber M., Wendisch C., Wüstenfeld J., Yurevich S., and Zanevsky Y.

Subjects
Physics, QC1-999
Abstract

New results on the differential cross section in deuteron-proton elastic scattering are obtained at the deuteron kinetic energy of 2.5 GeV with the HADES spectrometer. The angular range of 69° – 125° in the center of mass system is covered. The obtained results are compared with the relativistic multiple scattering model calculation using the CD-Bonn deuteron wave function. The data at fixed scattering angles in the c.m. are in qualitative agreement with the constituent counting rules prediction.

Published
2012
Full Text
View/download PDF

14. Resonance production in p+p, p+A and A+A collisions measured with HADES

Author

Reshetin A., Rehnisch L., Ramstein B., Przygoda W., Pietraszko J., Pechenova O., Pechenov V., Parpottas Y., Palka M., Naumann L., Münzer R., Müntz C., Michel J., Metag V., Markert J., Mangiarotti A., Maier L., Lopes L., Lebedev A., Lapidus K., Lang S., Lalik R., Ladygin V., Kurilkin P., Kurilkin A., Kurepin A., Kuc H., Kugler A., Krizek F., Krebs E., Krása A., Kotte R., Kornakov G., Korcyl G., Kolb B. W., Koenig W., Koenig I., Karavicheva T., Kämpfer B., Jurkovic M., Ivashkin A., Ierusalimov A., Höhne C., Huck P., Holzmann R., Hennino T., Harabasz S., Gumberidze M., Guber F., Gonzáalez-Díaz D., Golubeva M., Gill K., Garzón J. A., Galatyuk T., Fröhlich I., Friese J., Fabbietti L., Fonte P., Epple E., Dybczak A., Dritsa C., Cabanelas P., Böhmer M., Blume C., Blanco A., Berger-Chen J.C., Belyaev A., Belver D., Behnke C., Agakishiev G., Lorenz M., Rustamov A., Sadovsky A., Salabura P., Scheib T., Schuldes H., Siebenson J., Sobolev Yu.G., Spataroe S., Ströbele H., Stroth J., Strzempek P., Sturm C., Svoboda O., Tarantola A., Teilab K., Tlusty P., Traxler M., Tsertos H., Vasiliev T., Wagner V., Weber M., Wendisch C., Wüstenfeld J., Yurevich S., and Zanevsky Y.

Subjects
Physics, QC1-999
Abstract

The knowledge of baryonic resonance properties and production cross sections plays an important role for the extraction and understanding of medium modifications of mesons in hot and/or dense nuclear matter. We present and discuss systematics on dielectron and strangeness production obtained with HADES on p+p, p+A and A+A collisions in the few GeV energy regime with respect to these resonances.

Published
2012
Full Text
View/download PDF

15. Study of the lateral distribution functions of electron and muon bundles using Trasgo detectors

Author

Álvarez-Díaz, A., Cabanelas, P., Fontenla, Y., and Garzón, J. A.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Nuclear Experiment
Abstract

Some of the main features of the new generation Trasgo detectors are their capability in measuring the incoming direction and the arrival time of secondary cosmic particles. They also offer the identification capability between muon and electrons and a rough calorimetry for electrons. Using ground-based stations, these properties allow for the development of new tools for the measurement of primary cosmic ray fluxes. In order to verify and quantify the suitability of Trasgo detectors, whether a single one or arrays of them, to provide reliable information of the properties (mass, energy, incoming direction) of primary cosmic rays we have started an initiative for the systematic study of the 'lateral distributions' displayed by electrons and muons, or by bundles of those particles, using MonteCarlo simulations. In a first approach, electrons and muons were produced in vertical showers from primary H, He, C and Fe nuclei, and with incoming energies limited to a maximum of 10$^{15}$ eV per nucleon. This choice represents a significant component of all secondary particles, which can be measured on Earth's surface. The lateral distributions study has been done at the two locations of Santiago de Compostela (Spain) and Livingston Island (Antarctica), where Trasgo detectors are either in operation, or will be operative in the near future.

Published
2019

16. Measurement of Nuclear Interaction Cross Sections towards Neutron-Skin Thickness Determination

Author

Ponnath, L., primary, Aumann, T., additional, Bertulani, C.A., additional, Gernhäuser, R., additional, Heil, M., additional, Almusidi, T., additional, Alvarez-Pol, H., additional, Atar, L., additional, Atkins, L., additional, Ayyad, Y., additional, Benlliure, J., additional, Boretzky, K., additional, Borge, M.J.G., additional, Bott, L.T., additional, Bruni, G., additional, Brückner, B., additional, Cabanelas, P., additional, Caesar, C., additional, Casarejos, E., additional, Cederkall, J., additional, Corsi, A., additional, Cortina-Gil, D., additional, Dueñas, J.A., additional, Duer, M., additional, Elekes, Z., additional, Escribano Rodriguez, S., additional, Fabbietti, L., additional, Falduto, A., additional, Feijoo, M., additional, Feijoo Fontan, M., additional, Fonseca, L.M., additional, Frotscher, A., additional, Galaviz, D., additional, Galiana, E., additional, García-Jiménez, G., additional, Gašparic̀, I., additional, Geraci, E.I., additional, Gillibert, A., additional, Gnoffo, B., additional, González Caamaño, D., additional, Graña González, A., additional, Göbel, K., additional, Hartig, A.-L., additional, Heinz, A., additional, Hensel, T., additional, Holl, M., additional, Horvat, A., additional, Jedele, A., additional, Jelavic̀ Malenica, D., additional, Jenegger, T., additional, Johansson, H.T., additional, Jonson, B., additional, Kalantar-Nayestanaki, N., additional, Kelic-Heil, A., additional, Kiselev, O.A., additional, Klenze, P., additional, Kresan, D., additional, Kröll, T., additional, Kudaibergenova, E., additional, Kurtulgil, D., additional, Körper, D., additional, Labiche, M., additional, Langer, C., additional, Lihtar, I., additional, Litvinov, Yu.A., additional, Löher, B., additional, Mayer, J., additional, Murillo Morales, S., additional, Nacher, E., additional, Nilsson, T., additional, Obertelli, A., additional, Panin, V., additional, Park, J., additional, Paschalis, S., additional, Perea, A., additional, Petri, M., additional, Pirrone, S., additional, Pohl, T., additional, Reifarth, R., additional, Rhee, H.-B., additional, Rodriguez-Sanchez, J.L., additional, Rose, L., additional, Rossi, D.M., additional, Russotto, P., additional, Savran, D., additional, Scheit, H., additional, Simon, H., additional, Storck-Dutine, S., additional, Stott, A.M., additional, Sürder, C., additional, Taniuchi, R., additional, Tengblad, O., additional, Teubig, P., additional, Trache, L., additional, Trimarchi, M., additional, Törnqvist, H.T., additional, Varga, L., additional, Wagner, V., additional, and Wamers, F., additional

Published
2024
Full Text
View/download PDF

18. A new Time-of-flight detector for the R3B setup

Author

Heil, M., Kelić-Heil, A., Bott, L., Almusidi, T., Alvarez-Pol, H., Atar, L., Atkins, L., Aumann, T., Benlliure, J., Boretzky, K., Brückner, B., Cabanelas, P., Caesar, C., Casarejos, E., Cederkall, J., Chulkov, L., Corsi, A., Dueñas, J., Erbacher, P., Rodriguez, S. Escribano, Falduto, A., Feijoo, M., Frotscher, A., Frühauf, J., Gašparić, I., Borge, M. J. G., Gerbig, J., Gernhäuser, R., Gilbert, M., Glorius, J., Gnoffo, B., Göbel, K., Caamaño, D. Gonzalez, Grein, A., Hartig, A.-L., Heggen, H., Heine, M., Heinz, A., Holl, M., Homm, I., Horvat, A., Johansson, H. T., Jonson, B., Kalantar-Nayestanaki, N., Kamenyero, A., Khodaparast, A., Kiselev, O., Klenze, P., Knösel, M., Koch, K., Körper, D., Kröll, T., Kurtulgil, D., Kurz, N., Löher, B., Langer, C., Lehr, C., Litvinov, Y., Liu, H., Morales, S. Murillo, Nácher, E., Nilsson, T., Park, J., Paschalis, S., Pellegri, L., Perea, A., Petri, M., Pohl, T., Ponnath, L., Popočovski, R., Reifarth, R., Rhee, H.-B., Sanchez, J. L. Rodriguez, Rossi, D., Sürder, C., Sánchez-Benítez, A. M., Savran, D., Scheit, H., Simon, H., Slavkovská, Z., Storck-Dutine, S., Sun, Y., Törnqvist, H. T., Tanaka, J., Tengblad, O., Thomas, B., Varga, L., Volknandt, M., Wagner, V., Wamers, F., and Zanetti, L.

Published
2022
Full Text
View/download PDF

19. Analysis of pion production data measured by HADES in proton-proton collisions at 1.25 GeV

Author

Agakishiev, G., Balanda, A., Belver, D., Belyaev, A., Berger-Chen, J. C., Blanco, A., Böhmer, M., Boyard, J. L., Cabanelas, P., Chernenko, S., Dybczak, A., Epple, E., Fabbietti, L., Fateev, O., Finocchiaro, P., Fonte, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzón, J. A., Gernhäuser, R., Göbel, K., Golubeva, M., González-Díaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Ierusalimov, A., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kornakov, G., Kotte, R., Krása, A., Krizek, F., Krücken, R., Kuc, H., Kühn, W., Kugler, A., Kurepin, A., Ladygin, V., Lalik, R., Lang, S., Lapidus, K., Lebedev, A., Liu, T., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michalska, B., Michel, J., Müntz, C., Münzer, R., Naumann, L., Pachmayer, Y. C., Palka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Schmah, A., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spataro, S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Trebacz, R., Tsertos, H., Vasiliev, T., Wagner, V., Weber, M., Wendisch, C., Wüstenfeld, J., Yurevich, S., Zanevsky, Y., Sarantsev, A. V., and Nikonov, V. A.

Subjects
Nuclear Experiment, J.2
Abstract

Baryon resonance production in proton-proton collisions at a kinetic beam energy of 1.25 GeV is investigated. The multi-differential data were measured by the HADES collaboration. Exclusive channels with one pion in the final state ($np\pi^{+}$ and $pp\pi^{0}$) were put to extended studies based on various observables in the framework of a one-pion exchange model and with solutions obtained within the framework of a partial wave analysis (PWA) of the Bonn-Gatchina group. The results of the PWA confirm the dominant contribution of the $\Delta$(1232), yet with a sizable impact of the $N$(1440) and non-resonant partial waves., Comment: 12 pages, 6 figures

Published
2017
Full Text
View/download PDF

20. TRAGALDABAS. First results on cosmic ray studies and their relation with the solar activity, the Earth magnetic field and the atmospheric properties

Author

Garzón, J. A., Collazo, J., Cuenca-García, J., Castro, D. Garcí a, Otero, J., Yermo, M., Blanco, J. J., Kurtukian, T., Morozova, A., Pais, M. A., Blanco, A., Fonte, P., Lopes, L., Kornakov, G., Álvarez-Pol, H., Cabanelas, P., Pazos, A., Seco, M., Riádigos, I., Muñuzuri, V. Pérez, Gómez-Tato, A., Mouriño, J. C., Rey, P., and Taboada, J.

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics, Physics - Instrumentation and Detectors
Abstract

Cosmic rays originating from extraterrestrial sources are permanently arriving at Earth atmosphere, where they produce up to billions of secondary particles. The analysis of the secondary particles reaching to the surface of the Earth may provide a very valuable information about the Sun activity, changes in the geomagnetic field and the atmosphere, among others. In this article, we present the first preliminary results of the analysis of the cosmic rays measured with a high resolution tracking detector, TRAGALDABAS, located at the Univ. of Santiago de Compostela, in Spain., Comment: XXV ECRS 2016 Proceedings - eConf TBA

Published
2017

21. The TRASGO Project. Present Status and Results

Author

García-Castro, D., Ajoor, M., Alvarez-Pol, H., Blanco, A., Cabanelas, P., Callón-Rivas, J., Collazo, J., Clemencio, F., Cuenca-García, J. J., Cruces, M., Fonte, P., Fontenla, Y., Flores, J., Garzón, J. A., Gomis-Moreno, A., Iglesias, A., Kornakov, G., Kurtukian-Nieto, T., Lopes, L., Loureiro, C., Pazos, A., Rodríguez, C., Saraiva, J. P., Seco, M., Valladares, M., Villasante-Marcos, V., and Xuna, J.

Published
2021
Full Text
View/download PDF

22. Cross Sections for proton induced high energy $\gamma$-ray emission (PIGE) in reaction $^{19}$F(p,$\alpha\gamma$)$^{16}$O at incident proton energies between 1.5 and 4 MeV

Author

Cabanelas, P., Cruz, J., Fonseca, M., Henriques, A., Lourenço, F., Luís, H., Machado, J., Ribeiro, J. Pires, Sánchez-Benítez, A., Teubig, P., Velho, P., Zarza-Moreno, M., Galaviz, D., and Jesus, A. P.

Subjects
Nuclear Experiment
Abstract

We have studied the high energy gamma-rays produced in the reaction $^{19}$F(p,$\alpha\gamma$)$^{16}$O for incident proton energies from 1.5 to 4.0 MeV over NaF/Ag and CaF$_2$/Ag thin targets in two different sets of data. Gamma-rays were detected with a High Purity Ge detector with an angle of 130$^{o}$ with respect to the beam axis. The cross-sections for the high energy gamma-rays of 6.129, 6.915 and 7.115 MeV have been measured for the whole group between 5 and 7.2 MeV with accuracy better than 10\%. A new energy range was covered and more points are included in the cross-sections data base expanding the existing set of data. Results are in agreement with previous measurements in similar conditions., Comment: 5 pages, 5 figures

Published
2016
Full Text
View/download PDF

23. Preparation of Silver and Silver-backing self-supported thin targets by high vacuum evaporation

Author

Cabanelas, P., Galaviz, D., Henriques, A., Sánchez-Benítez, A., Teubig, P., and Velho, P.

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract

We have produced in the Nuclear Physics Center in Lisbon thin film self-supported targets of Ag, LiF/Ag and CaF$_2$/Ag by a high vacuum resistance evaporation method. The production setup, materials, methods, characterization and results are described., Comment: This paper has been withdrawn by the author due to a not proper description of the experimental enviroment

Published
2016

24. Statistical model analysis of hadron yields in proton-nucleus and heavy-ion collisions at SIS 18 energies

Author

Agakishiev, G., Arnold, O., Balanda, A., Belver, D., Belyaev, A., Berger-Chen, J. C., Blanco, A., Böhmer, M., Boyard, J. L., Cabanelas, P., Castro, E., Chernenko, S., Destefanis, M., Dohrmann, F., Dybczak, A., Epple, E., Fabbietti, L., Fateev, O., Finocchiaro, P., Fonte, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzon, J. A., Gernhäuser, R., Gilardi, C., Göbel, K., Golubeva, M., Gonzalez-Diaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Ierusalimov, A., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kornakov, G., Kotte, R., Krasa, A., Krizek, F., Krücken, R., Kuc, H., Kühn, W., Kugler, A., Kurepin, A., Ladygin, V., Lalik, R., Lange, J. S., Lang, S., Lapidus, K., Lebedev, A., Liu, T., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michalska, B., Michel, J., Moriniere, E., Mousa, J., Müntz, C., Münzer, R., Naumann, L., Pachmayer, Y. C., Palka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Rehnisch, L., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Scheib, T., Schmah, A., Schuldes, H., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spataro, S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Trebacz, R., Tsertos, H., Vasiliev, T., Wagner, V., Weber, M., Wendisch, C., Wisniowski, M., Wüstenfeld, J., Yurevich, S., and Zanevsky, Y.

Subjects
Nuclear Experiment, High Energy Physics - Experiment, Nuclear Theory
Abstract

The HADES data from p+Nb collisions at center of mass energy of $\sqrt{s_{NN}}$= 3.2 GeV are analyzed by employing a statistical model. Accounting for the identified hadrons $\pi^0$, $\eta$, $\Lambda$, $K^{0}_{s}$, $\omega$ allows a surprisingly good description of their abundances with parameters $T_{chem}=(99\pm11)$ MeV and $\mu_{b}=(619\pm34)$ MeV, which fits well in the chemical freeze-out systematics found in heavy-ion collisions. In supplement we reanalyze our previous HADES data from Ar+KCl collisions at $\sqrt{s_{NN}}$= 2.6 GeV with an updated version of the statistical model. We address equilibration in heavy-ion collisions by testing two aspects: the description of yields and the regularity of freeze-out parameters from a statistical model fit. Special emphasis is put on feed-down contributions from higher-lying resonance states which have been proposed to explain the experimentally observed $\Xi^-$ excess present in both data samples.

Published
2015

25. Simulations of light collection in long tapered CsI(Tl) scintillators using real crystal surface data and comparisons to measurement

Author

Knyazev, A., Park, J., Golubev, P., Cederkäll, J., Alvarez-Pol, H., Benlliure, J., Cabanelas, P., Casarejos, E., Causeret, L., Cortina-Gil, D., Fernández, P. Díaz, Feijoo, M., Galaviz, D., Galiana, E., Gernhäuser, R., Gonzalez, D., Hartig, A.-L., Heinz, A., Heiss, B., Johansson, H.T., Klenze, P., Kröll, T., Perea, A., Ponnath, L., Ren, Z., Rhee, H.-B., Rodriguez-Sanchez, J.L., Rondeau, G., Tengblad, O., Scheblykin, I.G., Teubig, P., and Timm, R.

Published
2021
Full Text
View/download PDF

26. Implemented occupational health surveillance limits the spread of SARS-CoV-2 Omicron at the workplace

Author

João Silveira Moledo Gesto, Adriana Cabanelas, Bruna Farjun, Monique Cristina dos Santos, Antonio A. Fidalgo-Neto, Sergio N. Kuriyama, and Thiago Moreno L. Souza

Subjects
COVID-19, SARS-CoV-2, occupational health, next generation sequencing – NGS, genomic surveillance, Medicine (General), R5-920
Abstract

The global spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has put an enormous pressure on human societies, at both health and economic levels. Early diagnosis of SARS-CoV-2, the causative agent of 2019 coronavirus disease (COVID-19), has proved an efficient method to rapidly isolate positive individuals and reduce transmission rates, thus alleviating its negative impact on society’s well-being and economic growth. In this work, through a coordinated and centralized effort to monitor SARS-CoV-2 circulation in companies from the State of Rio de Janeiro, Brazil, we have detected and linked an early rise of infection rates in January 2022 to the introduction of the Omicron variant of concern (VoC) (BA.1). Interestingly, when the Omicron genomic isolates were compared to correlates from public datasets, it was revealed that introduction events were multiple, with possible migration routes mapping to: Mali; Oman and United States; and Italy, Latin America, and United States. In addition, we have built a haplotype network with our genomic dataset and found no strong evidence of transmission chains, between and within companies. Considering Omicron’s particularly high transmissibility, and that most of our samples (>87%) arose from 3 out of 10 companies, these findings suggest that workers from such environments were exposed to SARS-CoV-2 outside their company boundaries. Thus, using a mixed strategy in which quick molecular diagnosis finds support in comprehensive genomic analysis, we have shown that a successfully implemented occupational health program should contribute to document emerging VoC and to limit the spread of SARS-CoV-2 at the workplace.

Published
2022
Full Text
View/download PDF

27. K*(892)+ production in proton-proton collisions at E_beam = 3.5 GeV

Author

HADES Collaboration, Agakishiev, G., Arnold, O., Belver, D., Belyaev, A., Berger-Chen, J. C., Blanco, A., Böhmer, M., Boyard, J. L., Cabanelas, P., Chernenko, S., Dybczak, A., Epple, E., Fabbietti, L., Fateev, O., Finocchiaro, P., Fonte, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzón, J. A., Gernhäuser, R., Göbel, K., Golubeva, M., González-Díaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Ierusalimov, A., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Korcyl, G., Kornakov, G., Kotte, R., Krása, A., Krizek, F., Krücken, R., Kuc, H., Kühn, W., Kugler, A., Kunz, T., Kurepin, A., Ladygin, V., Lalik, R., Lapidus, K., Lebedev, A., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michel, J., Mihaylov, D., Müntz, C., Münzer, R., Naumann, L., Pachmayer, Y. C., Palka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Schmah, A., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spataro, S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Svoboda, O., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Tsertos, H., Vasiliev, T., Wagner, V., Weber, M., Wendisch, C., Wüstenfeld, J., Yurevich, S., and Zanevsky, Y.

Subjects
Nuclear Experiment
Abstract

We present results on the K*(892)+ production in proton-proton collisions at a beam energy of E = 3.5 GeV, which is hitherto the lowest energy at which this mesonic resonance has been observed in nucleon-nucleon reactions. The data are interpreted within a two-channel model that includes the 3-body production of K*(892)+ associated with the Lambda- or Sigma-hyperon. The relative contributions of both channels are estimated. Besides the total cross section sigma(p+p -> K*(892)+ + X) = 9.5 +- 0.9 +1.1 -0.9 +- 0.7 mub, that adds a new data point to the excitation function of the K*(892)+ production in the region of low excess energy, transverse momenta and angular spectra are extracted and compared with the predictions of the two-channel model. The spin characteristics of K*(892)+ are discussed as well in terms of the spin-alignment., Comment: 7 pages, 9 figures, 1 table

Published
2015
Full Text
View/download PDF

28. Study of the quasi-free $np \to np \pi^+\pi^-$ reaction with a deuterium beam at 1.25 GeV/nucleon

Author

Agakishiev, G., Balanda, A., Belver, D., Belyaev, A. V., Blanco, A., Böhmer, M., Boyard, J. L., Braun-Munzinger, P., Cabanelas, P., Castro, E., Chernenko, S., Christ, T., Destefanis, M., Díaz, J., Dohrmann, F., Dybczak, A., Fabbietti, L., Fateev, O. V., Finocchiaro, P., Fonte, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzón, J. A., Gernhäuser, R., Gil, A., Gilardi, C., Göbel, K., Golubeva, M., González-Díaz, D., Guber, F., Gumberidze, M., Hennino, T., Holzmann, R., Ierusalimov, A., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Karavicheva, T., Kirschner, D., Koenig, I., Koenig, W., Kolb, B. W., Kotte, R., Krizek, F., Krücken, R., Kühn, W., Kugler, A., Kurepin, A., Kurilkin, A., Kurilkin, P., Ladygin, V., Lang, S., Lange, J. S., Lapidus, K., Liu, T., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michalska, B., Michel, J., Morinière, E., Mousa, J., Müntz, C., Naumann, L., Otwinowski, J., Pachmayer, Y. C., Palka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Schmah, A., Schwab, E., Sobolev, Yu. G., Spataro, S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Trebacz, R., Tsertos, H., Wagner, V., Vasiliev, T., Weber, M., Wisniowski, M., Wojcik, T., Wüstenfeld, J., Yurevich, S., Zanevsky, Y., and Zhou, P.

Subjects
Nuclear Experiment
Abstract

The tagged quasi-free $np \to np\pi^+\pi^-$ reaction has been studied experimentally with the High Acceptance Di-Electron Spectrometer (HADES) at GSI at a deuteron incident beam energy of 1.25 GeV/nucleon ($\sqrt s \sim$ 2.42 GeV/c for the quasi-free collision). For the first time, differential distributions for $\pi^{+}\pi^{-}$ production in $np$ collisions have been collected in the region corresponding to the large transverse momenta of the secondary particles. The invariant mass and angular distributions for the $np\rightarrow np\pi^{+}\pi^{-}$ reaction are compared with different models. This comparison confirms the dominance of the $t$-channel with $\Delta\Delta$ contribution. It also validates the changes previously introduced in the Valencia model to describe two-pion production data in other isospin channels, although some deviations are observed, especially for the $\pi^{+}\pi^{-}$ invariant mass spectrum. The extracted total cross section is also in much better agreement with this model. Our new measurement puts useful constraints for the existence of the conjectured dibaryon resonance at mass M$\sim$ 2.38 GeV and with width $\Gamma\sim$ 70 MeV.

Published
2015
Full Text
View/download PDF

29. Subthreshold Xi- Production in Collisions of p(3.5 GeV)+Nb

Author

Agakishiev, G., Arnold, O., Balanda, A., Belver, D., Belyaev, A. V., Berger-Chen, J. C., Blanco, A., Böhmer, M., Boyard, J. L., Cabanelas, P., Chernenko, S., Dybczak, A., Epple, E., Fabbietti, L., Fateev, O. V., Finocchiaro, P., Fonte, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzon, J. A., Gernhäuser, R., Göbel, K., Golubeva, M., Gonzalez-Diaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Ierusalimov, A., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kornakov, G., Kotte, R., Krasa, A., Krizek, F., Krücken, R., Kuc, H., Kühn, W., Kugler, A., Kurepin, A., Ladygin, V., Lalik, R., Lang, S., Lapidus, K., Lebedev, A., Liu, T., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michalska, B., Michel, J., Müntz, C., Naumann, L., Pachmayer, Y. C., Palka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Schmah, A., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spataro, S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Trebacz, R., Tsertos, H., Vasiliev, T., Wagner, V., Weber, M., Wendisch, C., Wüstenfeld, J., Yurevich, S., and Zanevsky, Y. V.

Subjects
Nuclear Experiment
Abstract

Results on the production of the double-strange cascade hyperon $\mathrm{\Xi^-}$ are reported for collisions of p\,(3.5~GeV)\,+\,Nb, studied with the High Acceptance Di-Electron Spectrometer (HADES) at SIS18 at GSI Helmholtzzentrum for Heavy-Ion Research, Darmstadt. For the first time, subthreshold $\mathrm{\Xi^-}$ production is observed in proton-nucleus interactions. Assuming a $\mathrm{\Xi^-}$ phase-space distribution similar to that of $\mathrm{\Lambda}$ hyperons, the production probability amounts to $P_{\mathrm{\Xi^-}}=(2.0\,\pm0.4\,\mathrm{(stat)}\,\pm 0.3\,\mathrm{(norm)}\,\pm 0.6\,\mathrm{(syst)})\times10^{-4}$ resulting in a $\mathrm{\Xi^-/(\Lambda+\Sigma^0)}$ ratio of $P_{\mathrm{\Xi^-}}/\ P_{\mathrm{\Lambda+\Sigma^0}}=(1.2\pm 0.3\,\mathrm{(stat)}\pm0.4\,\mathrm{(syst)})\times10^{-2}$. Available model predictions are significantly lower than the estimated $\mathrm{\Xi^-}$ yield., Comment: 6 pages, 3 figures

Published
2015
Full Text
View/download PDF

30. Tl concentration and its variation in a CsI(Tl) crystal for the CALIFA detector

Author

Knyazev, A., Park, J., Golubev, P., Pallon, J., Cederkall, J., Alvarez-Pol, H., Benlliure, J., Briz, J.A., Cabanelas, P., Casarejos, E., Cortina-Gil, D., Fernández, P. Díaz, Feijoo, M., Galaviz, D., Galiana, E., Borge, M.J.G., Gernhäuser, R., Gonzalez, D., Gutierrez-Neira, C., Hartig, A.-L., Heinz, A., Heiss, B., Johansson, H., Klenze, P., Kröll, T., Nilsson, T., Perea, A., Ponnath, L., Rhee, H.-B., Rodriguez-Sanchez, J.L., Tengblad, O., and Teubig, P.

Published
2020
Full Text
View/download PDF

31. Partial Wave Analysis of the Reaction $p(3.5 GeV)+p \to pK^+\Lambda$ to Search for the '$ppK^-$' Bound State

Author

Agakishiev, G., Arnold, O., Belver, D., Belyaev, A., Berger-Chen, J. C., Blanco, A., Böhmer, M., Boyard, J. L., Cabanelas, P., Chernenko, S., Dybczak, A., Epple, E., Fabbietti, L., Fateev, O., Finocchiaro, P., Fonte, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzón, J. A., Gernhäuser, R., Göbel, K., Golubeva, M., González-Díaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Ierusalimov, A., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kornakov, G., Kotte, R., Krasa, A., Krizek, F., Krücken, R., Kuc, H., Kühn, W., Kugler, A., Kunz, T., Kurepin, A., Ladygin, V., Lalik, R., Lapidus, K., Lebedev, A., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michel, J., Müntz, C., Münzer, R., Naumann, L., Pachmayer, Y. C., Palka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Schmah, A., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spataro, S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Tsertos, H., Vasiliev, T., Wagner, V., Weber, M., Wendisch, C., Wüstenfeld, J., Yurevich, S., Zanevsky, Y., and Sarantsev, A. V.

Subjects
Nuclear Experiment
Abstract

Employing the Bonn-Gatchina partial wave analysis framework (PWA), we have analyzed HADES data of the reaction $p(3.5GeV)+p\to pK^{+}\Lambda$. This reaction might contain information about the kaonic cluster "$ppK^-$" via its decay into $p\Lambda$. Due to interference effects in our coherent description of the data, a hypothetical $\overline{K}NN$ (or, specifically "$ppK^-$") cluster signal must not necessarily show up as a pronounced feature (e.g. a peak) in an invariant mass spectra like $p\Lambda$. Our PWA analysis includes a variety of resonant and non-resonant intermediate states and delivers a good description of our data (various angular distributions and two-hadron invariant mass spectra) without a contribution of a $\overline{K}NN$ cluster. At a confidence level of CL$_{s}$=95\% such a cluster can not contribute more than 2-12\% to the total cross section with a $pK^{+}\Lambda$ final state, which translates into a production cross-section between 0.7 $\mu b$ and 4.2 $\mu b$, respectively. The range of the upper limit depends on the assumed cluster mass, width and production process., Comment: 7 Pages, 5 Figures

Published
2014
Full Text
View/download PDF

32. Study of scintillation properties and performance of CsI(Tl) detectors over time

Author

García-Jiménez, G., primary, Cabanelas, P., additional, González-Caamaño, D., additional, Alvarez-Pol, H., additional, Vicente-Pardal, M.A., additional, Benlliure, J., additional, Cederkäll, J., additional, Cortina-Gil, D., additional, Feijoo-Fontán, M., additional, Graña-González, A., additional, and Rodríguez-Sánchez, J.L., additional

Published
2023
Full Text
View/download PDF

33. Medium effects in proton-induced $K^{0}$ production at 3.5 GeV

Author

Agakishiev, G., Arnold, O., Belver, D., Belyaev, A., Berger-Chen, J. C., Blanco, A., Böhmer, M., Boyard, J. L., Cabanelas, P., Chernenko, S., Dybczak, A., Epple, E., Fabbietti, L., Fateev, O., Finocchiaro, P., Fonte, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzón, J. A., Gernhäuser, R., Göbel, K., Golubeva, M., González-Díaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Ierusalimov, A., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Korcyl, G., Kornakov, G., Kotte, R., Krása, A., Krizek, F., Krücken, R., Kuc, H., Kühn, W., Kugler, A., Kunz, T., Kurepin, A., Ladygin, V., Lalik, R., Lapidus, K., Lebedev, A., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michel, J., Müntz, C., Münzer, R., Naumann, L., Pachmayer, Y. C., Palka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Schmah, A., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Tsertos, H., Vasiliev, T., Wagner, V., Weber, M., Wendisch, C., Wüstenfeld, J., Yurevich, S., Zanevsky, Y., Gaitanos, . T., and Weil, J.

Subjects
Nuclear Experiment
Abstract

We present the analysis of the inclusive $K^{0}$ production in p+p and p+Nb collisions measured with the HADES detector at a beam kinetic energy of 3.5 GeV. Data are compared to the GiBUU transport model. The data suggest the presence of a repulsive momentum-dependent kaon potential as predicted by the Chiral Perturbation Theory (ChPT). For the kaon at rest and at normal nuclear density, the ChPT potential amounts to $\approx 35$ MeV. A detailed tuning of the kaon production cross sections implemented in the model has been carried out to reproduce the experimental data measured in p+p collisions. The uncertainties in the parameters of the model were examined with respect to the sensitivity of the experimental results from p+Nb collisions to the in-medium kaon potential., Comment: 13 pages, 14 figures

Published
2014
Full Text
View/download PDF

34. Lambda hyperon production and polarization in collisions of p(3.5 GeV) + Nb

Author

Agakishiev, G., Arnold, O., Balanda, A., Belver, D., Belyaev, A. V., Berger-Chen, J. C., Blanco, A., Böhmer, M., Boyard, J. L., Cabanelas, P., Chernenko, S., Dybczak, A., Epple, E., Fabbietti, L., Fateev, O. V., Finocchiaro, P., Fonte, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzon, J. A., Gernhäuser, R., Göbel, K., Golubeva, M., Gonzalez-Díaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Ierusalimov, A., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kornakov, G., Kotte, R., Krasa, A., Krizek, F., Krücken, R., Kuc, H., Kühn, W., Kugler, A., Kurepin, A., Ladygin, V., Lalik, R., Lang, S., Lapidus, K., Lebedev, A., Liu, T., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michalska, B., Michel, J., Müntz, C., Naumann, L., Pachmayer, Y. C., Palka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Schmah, A., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spataro, S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Trebacz, R., Tsertos, H., Vasiliev, T., Wagner, V., Weber, M., Wendisch, C., Wüstenfeld, J., Yurevich, S., and Zanevsky, Y. V.

Subjects
Nuclear Experiment
Abstract

Results on $\Lambda$ hyperon production are reported for collisions of p(3.5 GeV) + Nb, studied with the High Acceptance Di-Electron Spectrometer (HADES) at SIS18 at GSI Helmholtzzentrum for Heavy-Ion Research, Darmstadt. The transverse mass distributions in rapidity bins are well described by Boltzmann shapes with a maximum inverse slope parameter of about $90\,$MeV at a rapidity of $y=1.0$, i.e. slightly below the center-of-mass rapidity for nucleon-nucleon collisions, $y_{cm}=1.12$. The rapidity density decreases monotonically with increasing rapidity within a rapidity window ranging from 0.3 to 1.3. The $\Lambda$ phase-space distribution is compared with results of other experiments and with predictions of two transport approaches which are available publicly. None of the present versions of the employed models is able to fully reproduce the experimental distributions, i.e. in absolute yield and in shape. Presumably, this finding results from an insufficient modelling in the transport models of the elementary processes being relevant for $\Lambda$ production, rescattering and absorption. The present high-statistics data allow for a genuine two-dimensional investigation as a function of phase space of the self-analyzing $\Lambda$ polarization in the weak decay $\Lambda\rightarrow p \pi^-$. Finite negative values of the polarization in the order of $5-20\,\%$ are observed over the entire phase space studied. The absolute value of the polarization increases almost linearly with increasing transverse momentum for $p_t>300\,$MeV/c and increases with decreasing rapidity for $y < 0.8$., Comment: accepted by Eur. Phys. J. A

Published
2014
Full Text
View/download PDF

35. Associate K^0 production in p+p collisions at 3.5 GeV: The role of Delta(1232)++

Author

Agakishiev, G., Arnold, O., Balanda, A., Belver, D., Belyaev, A., Berger-Chen, J. C., Blanco, A., Böhmer, M., Boyard, J. L., Cabanelas, P., Chernenko, S., Dybczak, A., Epple, E., Fabbietti, L., Fateev, O., Finocchiaro, P., Fonte, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzón, J. A., Gernhäuser, R., Göbel, K., Golubeva, M., González-Díaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Ierusalimov, A., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kornakov, G., Kotte, R., Krása, A., Krizek, F., Krücken, R., Kuc, H., Kühn, W., Kugler, A., Kunz, T., Kurepin, A., Ladygin, V., Lalik, R., Lang, S., Lapidus, K., Lebedev, A., Liu, T., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michalska, B., Michel, J., Münzer, R., Müntz, C., Naumann, L., Pachmayer, Y. C., Palka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Schmah, A., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spataro, S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Trebacz, R., Tsertos, H., Vasiliev, T., Wagner, V., Weber, M., Wendisch, C., Wustenfeld, J., Yurevich, S., and Zanevsky, Y.

Subjects
Nuclear Experiment
Abstract

An exclusive analysis of the 4-body final states $\mathrm{\Lambda + p + \pi^{+} + K^{0}}$ and $\mathrm{\Sigma^{0} + p + \pi^{+} + K^{0}}$ measured with HADES for p+p collisions at a beam kinetic energy of 3.5 GeV is presented. The analysis uses various phase space variables, such as missing mass and invariant mass distributions, in the four particle event selection (p, $\pi^+$, $\pi^+$, $\pi^-$) to find cross sections of the different production channels, contributions of the intermediate resonances $\mathrm{\Delta^{++}}$ and $\mathrm{\Sigma(1385)^{+}}$ and corresponding angular distributions. A dominant resonant production is seen, where the reaction $\mathrm{\Lambda + \Delta^{++} + K^{0}}$ has an about ten times higher cross section ($\mathrm{29.45\pm0.08^{+1.67}_{-1.46}\pm2.06\,\mu b}$) than the analogous non-resonant reaction ($\mathrm{2.57\pm0.02^{+0.21}_{-1.98}\pm0.18\,\mu b}$). A similar result is obtained in the corresponding $\Sigma^{0}$ channels with $\mathrm{9.26\pm0.05^{+1.41}_{-0.31}\pm0.65\,\ mu b}$ in the resonant and $\mathrm{1.35\pm0.02^{+0.10}_{-1.35}\pm0.09\,\mu b}$ in the non-resonant reactions., Comment: 12 pages, 11 figures

Published
2014
Full Text
View/download PDF

36. Baryon resonance production and dielectron decays in proton-proton collisions at 3.5 GeV

Author

Agakishiev, G., Balanda, A., Belver, D., Belyaev, A., Berger-Chen, J. C., Blanco, A., Böhmer, M., Boyard, J. L., Cabanelas, P., Chernenko, S., Dybczak, A., Epple, E., Fabbietti, L., Fateev, O., Finocchiaro, P., Fonte, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzón, J. A., Gernhäuser, R., Göbel, K., Golubeva, M., González-Díaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Ierusalimov, A., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Karavicheva, T., König, I., König, W., Kolb, B. W., Kornakov, G., Kotte, R., Krása, A., Krizek, F., Krücken, R., Kuc, H., Kühn, W., Kugler, A., Kurepin, A., Ladygin, V., Lalik, R., Lang, S., Lapidus, K., Lebedev, A., Liu, T., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michalska, B., Michel, J., Müntz, C., Naumann, L., Pachmayer, Y. C., Pałka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Schmah, A., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spataro, S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Trebacz, R., Tsertos, H., Vasiliev, T., Wagner, V., Weber, M., Wendisch, C., Wüstenfeld, J., Yurevich, S., and Zanevsky, Y.

Subjects
Nuclear Experiment, J.2
Abstract

We report on baryon resonance production and decay in proton-proton collisions at a kinetic energy of $3.5$ GeV based on data measured with HADES. The exclusive channels $pp \rightarrow np\pi^{+}$ and $pp \rightarrow pp\pi^{0}$ as well as $pp \rightarrow ppe^{+}e^{-}$ are studied simultaneously for the first time. The invariant masses and angular distributions of the pion-nucleon systems were studied and compared to simulations based on a resonance model ansatz assuming saturation of the pion production by an incoherent sum of baryonic resonances (R) with masses $<2~$ GeV/$c^2$. A very good description of the one-pion production is achieved allowing for an estimate of individual baryon-resonance production-cross-sections which are used as input to calculate the dielectron yields from $R\rightarrow pe^+e^-$ decays. Two models of the resonance decays into dielectrons are examined assuming a point-like $RN \gamma^*$ coupling and the dominance of the $\rho$ meson. The results of model calculations are compared to data from the exclusive $ppe^{+}e^{-}$ channel by means of the dielectron and $pe^+e^-$ invariant mass distributions., Comment: 17 pages, 14 figures

Published
2014
Full Text
View/download PDF

38. Searching a Dark Photon with HADES

Author

HADES Collaboration, Agakishiev, G., Balanda, A., Belver, D., Belyaev, A., Berger-Chen, J. C., Blanco, A., Boehmer, M., Boyard, J. L., Cabanelas, P., Chernenko, S., Dybczak, A., Epple, E., Fabbbietti, L., Fateev, O., Finocchiaro, P., Fonte, P., Friese, J., Froehlich, I., Galatyuk, T., Garzon, J. A., Gernhaeuser, R., Goebel, K., Golubeva, M., Gonzalez-Diaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Ierusalimov, A., Iori, I., Ivashkin, A., Jurkovic, M., Kaempfer, B., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kornakov, G., Kotte, R., Krasa, A., Krizek, F., Kruecken, R., Kuc, H., Kuehn, W., Kugler, A., Kurepin, A., Ladygin, V., Lalik, R., Lang, S., Lapidus, K., Lebedev, A., Liu, T., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michalska, B., Michel, J., Muentz, C., Naumann, L., Pachmayer, Y. C., Palka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Petousis, V., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Scheib, T., Schuldes, H., Schmah, A., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spataro, S., Spruck, B., Stroebele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Trebacz, R., Tsertos, H., Vasiliev, T., Wagner, V., Weber, M., Wendisch, C., Wuestenfeld, J., Yurevich, S., and Zanevsky, Y.

Subjects
High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract

We present a search for the e+e- decay of a hypothetical dark photon, also names U vector boson, in inclusive dielectron spectra measured by HADES in the p (3.5 GeV) + p, Nb reactions, as well as the Ar (1.756 GeV/u) + KCl reaction. An upper limit on the kinetic mixing parameter squared epsilon^{2} at 90% CL has been obtained for the mass range M(U) = 0.02 - 0.55 GeV/c2 and is compared with the present world data set. For masses 0.03 - 0.1 GeV/c^2, the limit has been lowered with respect to previous results, allowing now to exclude a large part of the parameter region favoured by the muon g-2 anomaly. Furthermore, an improved upper limit on the branching ratio of 2.3 * 10^{-6} has been set on the helicity-suppressed direct decay of the eta meson, eta-> e+e-, at 90% CL.

Published
2013

39. An upper limit on hypertriton production in collisions of Ar(1.76 AGeV)+KCl

Author

HADES Collaboration, Agakishiev, G., Belver, D., Blanco, A., Böhmer, M., Boyard, J. L., Cabanelas, P., Castro, E., Chernenko, S., Destefanis, M., Dohrmann, F., Dybczak, A., Epple, E., Fabbietti, L., Fateev, O., Finocchiaro, P., Fonte, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzón, J. A., Gernhäuser, R., Gilardi, C., Golubeva, M., González-Díaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kotte, R., Krása, A., Krizek, F., Krücken, R., Kuc, H., Kühn, W., Kugler, A., Kurepin, A., Lang, S., Lange, J. S., Lapidus, K., Liu, T., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michalska, B., Miche, J., Morinière, E., Mousa, J., Müntz, C., Naumann, L., Pachmayer, Y. C., Palka, M., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Rehnisch, L., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Scheib, T., Schmah, A., Schuldes, H., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spatarof, S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Trebacz, R., Tsertos, H., Wagner, V., Weber, M., Wendisch, C., Wisniowski, M., Wüstenfeld, J., Yurevich, S., and Zanevsky, Y.

Subjects
Nuclear Experiment, High Energy Physics - Experiment
Abstract

A high-statistic data sample of Ar(1.76 AGeV)+KCl events recorded with HADES is used to search for a hypertriton signal. An upper production limit per centrality-triggered event of $1.04$ x $10^{-3}$ on the $3\sigma$ level is derived. Comparing this value with the number of successfully reconstructed $\Lambda$ hyperons allows to determine an upper limit on the ratio $N_{_{\Lambda}^3H}/N_{\Lambda}$, which is confronted with statistical and coalescence-type model calculations.

Published
2013

40. Inclusive pion and eta production in p+Nb collisions at 3.5 GeV beam energy

Author

Agakishiev, G., Balanda, A., Belver, D., Belyaev, A., Berger-Chen, J. C., Blanco, A., Boehmer, M., Boyard, J. L., Cabanelas, P., Chernenko, S., Dybczak, A., Epple, E., Fabbbietti, L., Fateev, O., Finocchiaro, P., Fonte, P., Friese, J., Froehlich, I., Galatyuk, T., Garzon, J. A., Gernhaeuser, R., Goebel, K., Golubeva, M., Gonzalez-Diaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Ierusalimov, A., Iori, I., Ivashkin, A., Jurkovic, M., Kaempfer, B., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kornakov, G., Kotte, R., Krasa, A., Krizek, F., Kruecken, R., Kuc, H., Kuehn, W., Kugler, A., Kurepin, A., Ladygin, V., Lalik, R., Lang, S., Lapidus, K., Lebedev, A., Liu, T., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michalska, B., Michel, J., Muentz, C., Naumann, L., Pachmayer, Y. C., Palka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Schmah, A., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spataro, S., Spruck, B., Stroebele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Trebacz, R., Tsertos, H., Vasiliev, T., Wagner, V., Weber, M., Wendisch, C., Wuestenfeld, J., Yurevich, S., and Zanevsky, Y.

Subjects
Nuclear Experiment
Abstract

Data on inclusive pion and eta production measured with the dielectron spectrometer HADES in the reaction p+93Nb at a kinetic beam energy of 3.5 GeV are presented. Our results, obtained with the photon conversion method, supplement the rather sparse information on neutral meson production in proton-nucleus reactions existing for this bombarding energy regime. The reconstructed e+e-e+e- transverse-momentum and rapidity distributions are confronted with transport model calculations, which account fairly well for both pi0 and eta production., Comment: 12 pages, 9 figures, submitted to Physical Review C

Published
2013
Full Text
View/download PDF

41. pK+\Lambda final state: towards the extraction of the ppK- contribution

Author

Fabbietti, L., Agakishiev, G., Balanda, A., Belver, D., Belyaev, A. V., Berger-Chen, J-C, Blanco, A., Böhmer, M., Boyard, J. L., Cabanelas, P., Castro, E., Chernenko, S., Christ, T., Destefanis, M., Dohrmann, F., Dybczak, A., Epple, E., Eberl, T., Fateev, O. V., Finocchiaro, P., Fonte, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzon, J. A., Gernhäuser, R., Gilardi, C., Golubeva, M., Gonzalez-Diaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Kanaki, K., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kotte, R., Krasa, A., Krizek, F., Krücken, R., Kuc, H., Kühn, W., Kugler, A., Kurepin, A., Lalik, R., Lang, S., Lange, J. S., Lapidus, K., Liu, T., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michalska, B., Michel, J., Moriniere, E., Mousa, J., Müntz, C., Naumann, L., Otwinowski, J., Pachmayer, Y. C., Palka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Schmah, A., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spataro, A. Solaguren-Beascoa Negre S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Trebacz, R., Tsertos, H., Wagner, V., Weber, M., Wendisch, C., Wüstenfel, J., Yurevich, S., and Zanevsky, Y. V.

Subjects
Nuclear Experiment
Abstract

The reaction p(@3.5\,GeV)+p -> p+\Lambda + K^+ can be studied to search for the existence of kaonic bound states like ppK^- leading to this final state. This effort has been motivated by the assumption that in p+p collisions the \Lambda(1405) resonance can act as a doorway to the formation of the kaonic bound states. The status of this analysis within the HADES collaboration, with particular emphasis on the comparison to simulations, is shown in this work and the deviation method utilized by the DISTO collaboration in a similar analysis is discussed. The outcome suggests the employment of a partial wave analysis to disentangle the different contributions to the measured pK^+\Lambda final state., Comment: 9 pages, 6 figures, proceeding of the HYP2012 conference Nucl. Phys. A (2013)

Published
2013
Full Text
View/download PDF

42. Baryonic resonances close to the Kbar-N threshold: the case of Lambda(1405) in pp collisions

Author

Agakishiev, G., Balanda, A., Belver, D., Belyaev, A. V., Berger-Chen, J. C., Blanco, A., Böhmer, M., Boyard, J. L., Cabanelas, P., Chernenko, S., Dybczak, A., Epple, E., Fabbietti, L., Finocchiaro, P., Fonte, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzón, J. A., Gernhäuser, R., Göbel, K., Golubeva, M., González-Díaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Ierusalimov, A., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kornakov, G., Kotte, R., Krása, A., Krizek, F., Krücken, R., Kuc, H., Kühn, W., Kugler, A., Kurepin, A., Ladygin, V., Lalik, R., Lang, S., Lapidus, K., Lebedev, A., Liu, T., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michalska, B., Michel, J., Müntz, C., Naumann, L., Pachmayer, Y. C., Palka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Schmah, A., Schwab, E., Siebenson, J., Spataro, S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Trebacz, R., Tsertos, H., Vasiliev, T., Wagner, V., Weber, M., Wendisch, C., Wüstenfel, J., Yurevich, S., and Zanevsky, Y. V.

Subjects
Nuclear Experiment
Abstract

We present an analysis of the Lambda(1405) resonance produced in the reaction p+p->Sigma^{pm}+pi^{mp}+K+p at 3.5 GeV kinetic beam energy measured with HADES at GSI. The two charged decay channels Lambda(1405) -> Sigma^{\pm}+pi^{\mp} have been reconstructed for the first time in p+p collisions. The efficiency and acceptance-corrected spectral shapes show a peak position clearly below 1400 MeV/c^2. We find a total production cross section of sigma_{Lambda(1405)}=9.2 +- 0.9 +- 0.7 +3.3-1.0 mub. The analysis of its polar angle distribution suggests that the Lambda(1405) is produced isotropically in the p-p center of mass system., Comment: 5 pages 3 figures

Published
2012
Full Text
View/download PDF

43. First measurement of low momentum dielectrons radiated off cold nuclear matter

Author

Agakishiev, G., Balanda, A., Belver, D., Belyaev, A., Berger-Chen, J. C., Blanco, A., Böhmer, M., Boyard, J. L., Cabanelas, P., Chernenko, S., Dybczak, A., Epple, E., Fabbietti, L., Fateev, O., Finocchiaro, P., Fonte, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzón, J. A., Gernhäuser, R., Göbel, K., Golubeva, M., González-Díaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Ierusalimov, A., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kornakov, G., Kotte, R., Krása, A., Krizek, F., Krücken, R., Kuc, H., Kühn, W., Kugler, A., Kurepin, A., Ladygin, V., Lalik, R., Lang, S., Lapidus, K., Lebedev, A., Liu, T., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michalska, B., Michel, J., Mishra, D., Müntz, C., Naumann, L., Pachmayer, Y. C., Palka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Schmah, A., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spataro, S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Trebacz, R., Tsertos, H., Vasiliev, T., Wagner, V., Weber, M., Wendisch, C., Wüstenfeld, J., Yurevich, S., and Zanevsky, Y.

Subjects
Nuclear Experiment, High Energy Physics - Experiment
Abstract

We present data on dielectron emission in proton induced reactions on a Nb target at 3.5 GeV kinetic beam energy measured with HADES installed at GSI. The data represent the first high statistics measurement of proton-induced dielectron radiation from cold nuclear matter in a kinematic regime, where strong medium effects are expected. Combined with the good mass resolution of 2%, it is the first measurement sensitive to changes of the spectral functions of vector mesons, as predicted by models for hadrons at rest or small relative momenta. Comparing the e+e invariant mass spectra to elementary p+p data, we observe for e+e momenta Pee < 0.8 GeV/c a strong modification of the shape of the spectrum, which we attribute to an additional rho-like contribution and a decrease of omega yield. These opposite trends are tentatively interpreted as a strong coupling of the rho meson to baryonic resonances and an absorption of the omega meson, which are two aspects of in-medium modification of vector mesons.

Published
2012
Full Text
View/download PDF

44. Inclusive dielectron production in proton-proton collisions at 2.2 GeV beam energy

Author

Agakishiev, G., Alvarez-Pol, H., Balanda, A., Bassini, R., Böhmer, M., Bokemeye, H., Boyard, J. L., Cabanelas, P., Chernenko, S., Christ, T., Destefanis, M., Dohrmann, F., Dybczak, A., Eberl, T., Fabbietti, L., Fateev, O., Finocchiaro, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzón, J. A., Gernhäuser, R., Gilardi, C., Golubeva, M., González-Díaz, D., Guber, F., Gumberidze, M., Hennino, T., Holzmann, R., Ierusalimov, A., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Kanaki, K., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kotte, R., Kozuch, A., Krizek, F., Kühn, W., Kugler, A., Kurepin, A., Lang, S., Lapidus, K., Liu, T., Maier, L., Markert, J., Metag, V., Michalska, B., Morinière, E., Mousa, J., Münch, M., Müntz, C., Naumann, L., Otwinowski, J., Pachmayer, Y. C., Pechenov, V., Pechenova, O., Cavalcanti, T. Perez, Pietraszko, J., Pospisil, V., Przygoda, W., Ramstein, B., Reshetin, A., Roy-Stephan, M., Rustamov, A., Sadovsky, A., Sailer, B., Salabura, P., Sánchez, M., Schmah, A., Schwab, E., Sobolev, Yu. G., Spataro, S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Toia, A., Traxler, M., Trebacz, R., Tsertos, H., Wagner, V., Wisniowski, M., Wojcik, T., Wüstenfeld, J., Yurevich, S., Zanevsky, Y., and Zumbruch, P.

Subjects
Nuclear Experiment
Abstract

Data on inclusive dielectron production are presented for the reaction p+p at 2.2 GeV measured with the High Acceptance DiElectron Spectrometer (HADES). Our results supplement data obtained earlier in this bombarding energy regime by DLS and HADES. The comparison with the 2.09 GeV DLS data is discussed. The reconstructed e+e- distributions are confronted with simulated pair cocktails, revealing an excess yield at invariant masses around 0.5 GeV/c2. Inclusive cross sections of neutral pion and eta production are obtained.

Published
2012
Full Text
View/download PDF

45. Study of exclusive one-pion and one-eta production using hadron and dielectron channels in pp reactions at kinetic beam energies of 1.25 GeV and 2.2 GeV with HADES

Author

HADES Collaboration, Agakishiev, G., Alvarez-Pol, H., Balanda, A., Bassini, R., Böhmer, M., Bokemeyer, H., Boyard, J. L., Cabanelas, P., Chernenko, S., Christ, T., Destefanis, M., Dohrmann, F., Dybczak, A., Eberl, T., Fabbietti, L., Fateev, O., Finocchiaro, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzón, J. A., Gernhäuser, R., Gilardi, C., Golubeva, M., González-Díaz, D., Guber, F., Gumberidze, M., Hennino, T., Holzmann, R., Ierusalimov, A., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Kanaki, K., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kotte, R., Kozuch, A., Krizek, F., Kühn, W., Kugler, A., Kurepin, A., Lang, S., Lapidus, K., Liu, T., Maier, L., Markert, J., Metag, V., Michalska, B., Morinière, E., Mousa, J., Münch, M., Müntz, C., Naumann, L., Otwinowski, J., Pachmayer, Y. C., Pechenov, V., Pechenova, O., Cavalcanti, T. Pérez, Pietraszko, J., Pospísil, V., Przygoda, W., Ramstein, B., Reshetin, A., Roy-Stephan, M., Rustamov, A., Sadovsky, A., Sailer, B., Salabura, P., Sánchez, M., Schmah, A., Schwab, E., Sobolev, Yu. G., Spataro, S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Toia, A., Traxler, M., Trebacz, R., Tsertos, H., Wagner, V., Wisniowski, M., Wojcik, T., Wüstenfeld, J., Yurevich, S., Zanevsky, Y., and Zumbruch, P.

Subjects
Nuclear Experiment
Abstract

We present measurements of exclusive \pi^{+,0} and \eta\ production in pp reactions at 1.25 GeV and 2.2 GeV beam kinetic energy in hadron and dielectron channels. In the case of \pi^+ and \pi^0, high-statistics invariant-mass and angular distributions are obtained within the HADES acceptance as well as acceptance corrected distributions, which are compared to a resonance model. The sensitivity of the data to the yield and production angular distribution of \Delta(1232) and higher lying baryon resonances is shown, and an improved parameterization is proposed. The extracted cross sections are of special interest in the case of pp \to pp \eta, since controversial data exist at 2.0 GeV; we find \sigma =0.142 \pm 0.022 mb. Using the dielectron channels, the \pi^0 and \eta\ Dalitz decay signals are reconstructed with yields fully consistent with the hadronic channels. The electron invariant masses and acceptance corrected helicity angle distributions are found in good agreement with model predictions., Comment: 22 pages, 18 figures, to be published in EPJA

Published
2012
Full Text
View/download PDF

46. Production of Sigma{\pm}pi?pK+ in p+p reactions at 3.5 GeV beam energy

Author

Agakishiev, G., Balanda, A., Belver, D., Belyaev, A., Berger-Chen, J. C., Blanco, A., Boehmer, M., Boyard, J. L., Cabanelas, P., Castro, E., Chernenko, S., Destefanis, T. Christ M., Dohrmann, F., Dybczak, A., Epple, E., Fabbietti, L., Fateev, O., Finocchiaro, P., Fonte, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzon, J. A., Gernhäuser, R., Gilardi, C., Golubeva, M., Gonza'lez-Di'az, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Ierusalimov, A., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Kanaki, K., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kotte, R., Kr'asa, A., Krizek, F., Krücken, R., Kuc, H., Kuehn, W., Kugler, A., Kurepin, A., Lalik, R., Lang, S., Lange, J. S., Lapidus, K., Liu, T., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michalska, B., Michel, J., Morinie're, E., Mousa, J., Müntz, C., Naumann, L., Otwinowski, J., Pachmayer, Y. C., Palka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Schmah, A., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spataro, S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Trebacz, R., Tsertos, H., Wagner, V., Weber, M., Wendisch, C., Wüstenfeld, J., Yurevich, S., and Zanevsky, Y.

Subjects
Nuclear Experiment
Abstract

We study the production of Sigma^+-pi^+-pK^+ particle quartets in p+p reactions at 3.5 GeV kinetic beam energy. The data were taken with the HADES experiment at GSI. This report evaluates the contribution of resonances like Lambda(1405$, Sigma(1385)^0, Lambda(1520), Delta(1232), N^* and K^*0 to the Sigma^+- pi^-+ p K+ final state. The resulting simulation model is compared to the experimental data in several angular distributions and it shows itself as suitable to evaluate the acceptance corrections properly., Comment: 15 pages, 5 figures

Published
2012
Full Text
View/download PDF

47. Determination of the $\mathbf{\Sigma(1385)^{0}/\Lambda(1405)}$ ratio in p+p collisions at 3.5 GeV

Author

Agakishiev, G., Balanda, A., Belver, D., Belyaev, A. V., Blanco, A., Böhmer, M., Boyard, J. L., Cabanelas, P., Castro, E., Chen, J. C., Chernenko, S., Christ, T., Destefanis, M., Dohrmann, F., Dybczak, A., Epple, E., Fabbietti, L., Fateev, O. V., Finocchiaro, P., Fonte, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzón, J. A., Gernhäuser, R., Gilardi, C., Golubeva, M., González-Díaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Kanaki, K., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kotte, R., Krása, A., Krizek, F., Krücken, R., Kuc, H., Kühn, W., Kugler, A., Kurepin, A., Lalik, R., Lang, S., Lange, J. S., Lapidus, K., Liu, T., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michalska, B., Michel, J., Morinière, E., Mousa, J., Müntz, C., Naumann, L., Otwinowski, J., Pachmayer, Y. C., Palka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Schmah, A., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spataro, S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Trebacz, R., Tsertos, H., Wagner, V., Weber, M., Wendisch, C., Wüstenfeld, J., Yurevich, S., and Zanevsky, Y. V.

Subjects
Nuclear Experiment
Abstract

The aim of the present analysis is to determine the relative production cross sections of the $\Lambda$(1405) and $\Sigma(1385)^{0}$ resonances in p+p collisions at E$_{kin}$=3.5 GeV measured with HADES. Upper and lower limits have been determined for the ratio $\sigma_{(\Sigma(1385)^{0}+p+K^{+})}/\sigma_{(\Lambda(1405)+p+K^{+})}=0.76_{-0.26}^{+0.54}$. The knowledge of this ratio is an essential input for the analysis of the decay $\Lambda(1405)\rightarrow\Sigma^{\pm}\pi^{\mp}$, where an unambiguous separation of the $\Lambda$(1405) and $\Sigma(1385)^{0}$ signals is not possible.

Published
2012
Full Text
View/download PDF

48. Inclusive dielectron spectra in p+p collisions at 3.5 GeV

Author

Agakishiev, G., Balanda, A., Belver, D., Belyaev, A., Blanco, A., Böhmer, M., Boyard, J. L., Cabanelas, P., Castro, E., Chen, J. C., Chernenko, S., Christ, T., Destefanis, M., Dohrmann, F., Dybczak, A., Epple, E., Fabbietti, L., Fateev, O., Finocchiaro, P., Fonte, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzón, J. A., Gernhäuser, R., Gilardi, C., Golubeva, M., González-Díaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Kanaki, K., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kotte, R., Krása, A., Krizek, F., Krücken, R., Kuc, H., Kühn, W., Kugler, A., Kurepin, A., Lalik, R., Lang, S., Lange, J. S., Lapidus, K., Liu, T., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michalska, B., Michel, J., Morinière, E., Mousa, J., Müntz, C., Naumann, L., Otwinowski, J., Pachmayer, Y. C., Palka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Schmah, A., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spataro, S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Trebacz, R., Tsertos, H., Wagner, V., Weber, M., Wendisch, C., Wüstenfeld, J., Yurevich, S., and Zanevsky, Y.

Subjects
Nuclear Experiment
Abstract

We present the inclusive invariant-mass, transverse momentum and rapidity distributions of dielectrons (e$^{+}$e$^{-}$ pairs) in p+p interactions at 3.5 GeV beam kinetic energy. In the vector-meson mass region, a distinct peak corresponding to direct $\omega$ decays is reconstructed with 2% mass resolution. The data is compared to predictions from three model calculations. Due to the large acceptance of the HADES apparatus for $e^{+}e^{-}$ invariant masses above 0.2 GeV/$c^{2}$ and for transverse pair momenta p$_{t}$ $ <$ 1 GeV/$c$, acceptance corrections are to a large extent model independent. This allows us to extract from dielectron data for the first time at this energy the inclusive production cross sections for light vector mesons. Inclusive production cross sections for $\pi^o$ and $\eta$ mesons are also reported. The obtained results will serve as an important reference for the study of vector meson production in proton-nucleus and heavy-ion collisions. Furthermore, using this data, an improved value for the upper bound of the branching ratio for direct $\eta$ decays into the electron-positron channel is obtained.

Published
2011
Full Text
View/download PDF

49. Baryonic resonances close to the Kbar-N threshold: the case of Sigma(1385)^+ in pp collisions

Author

Agakishiev, G., Balanda, A., Belver, D., Belyaev, A. V., Blanco, A., Boehmer, M., Boyard, J. L., Cabanelas, P., Castro, E., Chen, J. C., Chernenko, S., Christ, T., Destefanis, M., Dohrmann, F., Dybczak, A., Epple, E., Eberl, T., Fabbietti, L., Fateev, O. V., Finocchiaro, P., Fonte, P., Friese, J., Froehlich, I., Galatyuk, T., Garzon, J. A., Gernhaeuser, R., Gilardi, C., Golubeva, M., Gonzalez-Diaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Iori, I., Ivashkin, A., Jurkovic, M., Kaempfer, B., Kanaki, K., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kotte, R., Krasa, A., Krizek, F., Kruecken, R., Kuc, H., Kuehn, W., Kugler, A., Kurepin, A., Lalik, R., Lang, S., Lange, J. S., Lapidus, K., Liu, T., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michalska, B., Michel, J., Moriniere, E., Mousa, J., Muentz, C., Naumann, L., Otwinowski, J., Pachmayer, Y. C., Palka, M., Parpottas, Y., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Salabura, P., Schmah, A., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spataro, S., Spruck, B., Stroebele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Trebacz, R., Tsertos, H., Wagner, V., Weber, M., Wendisch, C., Wuestenfeld, J., Yurevich, S., and Zanevsky, Y. V.

Subjects
Nuclear Experiment
Abstract

We present results of an exclusive measurement of the first excited state of the Sigma hyperon, Sigma(1385)^+, produced in p+p -> Sigma^+ + K^+ + n at 3.5 GeV beam energy. The extracted data allow to study in detail the invariant mass distribution of the Sigma(1385)^+. The mass distribution is well described by a relativistic Breit-Wigner function with a maximum at m_0 = 1383.2 +- 0.9 MeV/c^2 and a width of 40.2 +- 2.1 MeV/c^2. The exclusive production cross-section comes out to be 22.27 +- 0.89 +- 1.56 +3.07 -2.10 mu b. Angular distributions of the Sigma(1385)^+ in different reference frames are found to be compatible with the hypothesis that 33 % of Sigma(1385)^+ result from the decay of an intermediate Delta^{++} resonance., Comment: 12 pages; 12 figures; submitted to PRC

Published
2011
Full Text
View/download PDF

50. Dielectron production in Ar+KCl collisions at 1.76A GeV

Author

Agakishiev, G., Balanda, A., Belver, D., Belyaev, A., Blanco, A., Böhmer, M., Boyard, J. L., Cabanelas, P., Castro, E., Chernenko, S., Christ, T., Destefanis, M., Dohrmann, F., Dybczak, A., Eberl, T., Epple, E., Fabbbietti, L., Fateev, O., Finocchiaro, P., Fonte, P., Friese, J., Fröhlich, I., Galatyuk, T., Garzon, J. A., Gernhäuser, R., Gilardi, C., Golubeva, M., Gonzalez-Díaz, D., Guber, F., Gumberidze, M., Heinz, T., Hennino, T., Holzmann, R., Huck, P., Iori, I., Ivashkin, A., Jurkovic, M., Kämpfer, B., Kanaki, K., Karavicheva, T., Koenig, I., Koenig, W., Kolb, B. W., Kotte, R., Krasa, A., Krizek, F., Krücken, R., Kuc, H., Kühn, W., Kugler, A., Kurepin, A., Lang, S., Lange, J. S., Liu, K. Lapidus T., Lopes, L., Lorenz, M., Maier, L., Mangiarotti, A., Markert, J., Metag, V., Michalska, B., Michel, J., Moriniere, E., Mousa, J., Müntz, C., Naumann, L., Otwinowski, J., Pachmayer, Y. C., Palka, M., Pechenov, V., Pechenova, O., Pietraszko, J., Przygoda, W., Ramstein, B., Reshetin, A., Rustamov, A., Sadovsky, A., Sailer, B., Salabura, P., Schmah, A., Schwab, E., Siebenson, J., Sobolev, Yu. G., Spataro, S., Spruck, B., Ströbele, H., Stroth, J., Sturm, C., Tarantola, A., Teilab, K., Tlusty, P., Traxler, M., Trebacz, R., Tsertos, H., Wagner, V., Weber, M., Wendisch, C., Wisniowski, M., Wüstenfeld, J., Yurevich, S., and Zanevsky, Y.

Subjects
Nuclear Experiment
Abstract

We present results on dielectron production in Ar+KCl collisions at 1.76A GeV. For the first time $\omega$ mesons could be reconstructed in a heavy-ion reaction at a bombarding energy which is well below the production threshold in free nucleon-nucleon collisions. The omega multiplicity has been extracted and compared to the yields of other particles, in particular of the phi meson. At intermediate e+e- invariant masses, we find a strong enhancement of the pair yield over a reference spectrum from elementary nucleon-nucleon reactions suggesting the onset of non-trivial effects of the nuclear medium. Transverse-mass spectra and angular distributions have been reconstructed in three invariant mass bins. In the former unexpectedly large slopes are found for high-mass pairs. The latter, in particular the helicity-angle distributions, are largely consistent with expectations for a pair cocktail dominated at intermediate masses by delta Dalitz decays., Comment: 16 pages, 14 figures, accepted for publication by Phys. Rev. C

Published
2011
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results