Search

Your search keyword '"Alfons Khoukaz"' showing total 64 results
Start Over Author "Alfons Khoukaz"
64 results on '"Alfons Khoukaz"'

2. Amplitude analysis and branching-fraction measurement of Ds+→KS0K−π+π+

Author

Stefano Spataro, Antonio Amoroso, Ilaria BALOSSINO, Meike Kuessner, Hajime Muramatsu, Michela Greco, Alexey Zhemchugov, Riccardo Farinelli, Riccardo Aliberti, Lia Lavezzi, Jens Sören Lange, Onur Bugra Kolcu, Alfons Khoukaz, Marco Giovanni Maria Destefanis, Patrik Adlarson, Mikhail Achasov, Johan Messchendorp, Ralf Kliemt, Hongrong Qi, Giulio Mezzadri, Alberto Bortone, Fabio Cossio, and Karin Schoenning

Subjects
Nuclear physics, Physics, Amplitude, 010308 nuclear & particles physics, Branching fraction, 0103 physical sciences, Detector, 010306 general physics, Collision, 01 natural sciences
Abstract

Using 6.32 fb−1 of e+e− collision data collected by the BESIII detector at the center-of-mass energies between 4.178 and 4.226 GeV, an amplitude analysis of the D+s → K0SK−π+π+ decays is performed ...

Published
2021
Full Text
View/download PDF

3. Determination of the Λc+ spin via the reaction e+e−→ΛcΛ¯c

Author

Stefano Spataro, Antonio Amoroso, Ilaria BALOSSINO, Meike Kuessner, Yunxuan Song, Hajime Muramatsu, Michela Greco, Alexey Zhemchugov, Qiang Zhao, Riccardo Farinelli, Riccardo Aliberti, Lia Lavezzi, Jens Sören Lange, Liaoyuan Dong, Francesca De Mori, Onur Bugra Kolcu, Alfons Khoukaz, Yuxiang Zhao, Marco Giovanni Maria Destefanis, Weimin Song, Patrik Adlarson, Mikhail Achasov, Johan Messchendorp, Ralf Kliemt, Hongrong Qi, Peirong Li, Xiang Liu, Giulio Mezzadri, Alberto Bortone, Fabio Cossio, and Karin Schoenning

Subjects
Physics, 010308 nuclear & particles physics, 0103 physical sciences, Atomic physics, 010306 general physics, 01 natural sciences, Spin-½
Abstract

We report on a comparison of two possible Λ+c spin hypotheses, J=½ and 3/2, via the process e+e− → Λ+c¯Λ−c, using the angular distributions of Λ+c decays into pK0S, Λπ+, Σ0π+, and Σ+π0. The data we ...

Published
2021
Full Text
View/download PDF

4. Search for the semileptonic decay D0(+)→b1(1235)−(0)e+νe

Author

Stefano Spataro, Antonio Amoroso, Ilaria BALOSSINO, Meike Kuessner, Yunxuan Song, Alessio Mangoni, Hajime Muramatsu, Michela Greco, Alexey Zhemchugov, Qiang Zhao, Riccardo Farinelli, Riccardo Aliberti, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Liaoyuan Dong, Francesca De Mori, Onur Bugra Kolcu, Alfons Khoukaz, Yuxiang Zhao, Marco Giovanni Maria Destefanis, Weimin Song, Vindhyawasini Prasad, Banzragch Tsednee, Patrik Adlarson, Mikhail Achasov, Johan Messchendorp, Ralf Kliemt, Hongrong Qi, Peirong Li, Xiang Liu, Giulio Mezzadri, Alberto Bortone, Fabio Cossio, and Karin Schoenning

Subjects
Semileptonic decay, Physics, Particle physics, Annihilation, Physics::Instrumentation and Detectors, 010308 nuclear & particles physics, Detector, 01 natural sciences, law.invention, law, 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Collider, Energy (signal processing)
Abstract

Using 2.93 fb−1 of e+e− annihilation data collected at a center-of-mass energy √s=3.773 GeV with the BESIII detector operating at the BEPCII collider, we search for the semileptonic D0(+) decays ...

Published
2020
Full Text
View/download PDF

5. Improved model-independent determination of the strong-phase difference between D0 and D¯0→KS,L0K+K− decays

Author

Stefano Spataro, Antonio Amoroso, Ilaria BALOSSINO, Meike Kuessner, Yunxuan Song, Alessio Mangoni, Hajime Muramatsu, Michela Greco, Alexey Zhemchugov, Qiang Zhao, Riccardo Farinelli, Anatoliy Guskov, Riccardo Aliberti, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Liaoyuan Dong, Francesca De Mori, Onur Bugra Kolcu, Alfons Khoukaz, Yuxiang Zhao, Marco Giovanni Maria Destefanis, Weimin Song, Krishnakumar Ravindran, Banzragch Tsednee, Patrik Adlarson, Mikhail Achasov, Johan Messchendorp, Ralf Kliemt, Hongrong Qi, Peirong Li, Xiang Liu, Giulio Mezzadri, Alberto Bortone, Fabio Cossio, and Karin Schoenning

Subjects
Phase difference, Physics, Particle physics, Meson, 010308 nuclear & particles physics, Bar (music), High Energy Physics::Phenomenology, 0103 physical sciences, High Energy Physics::Experiment, Charm (quantum number), Nuclear Experiment, 010306 general physics, 01 natural sciences
Abstract

We present a measurement of the strong-phase difference between D-0 and (D) over bar (0) -> (KS,LK+K-)-K-0 decays, performed through a study of quantum-entangled pairs of charm mesons. The measu ...

Published
2020
Full Text
View/download PDF

6. Inclusive charged and neutral particle multiplicity distributions in χcJ and J/ψ decays

Author

Stefano Spataro, Antonio Amoroso, Ilaria BALOSSINO, Meike Kuessner, Alessio Mangoni, Hajime Muramatsu, Michela Greco, Alexey Zhemchugov, Riccardo Farinelli, Anatoliy Guskov, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Onur Bugra Kolcu, Alfons Khoukaz, Marco Giovanni Maria Destefanis, Vindhyawasini Prasad, Banzragch Tsednee, Patrik Adlarson, Mikhail Achasov, Johan Messchendorp, Ralf Kliemt, Hongrong Qi, Xiang Liu, Giulio Mezzadri, Alberto Bortone, Tord Johansson, Fabio Cossio, and Karin Schoenning

Subjects
Physics, Particle physics, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, 0103 physical sciences, High Energy Physics::Experiment, Multiplicity (chemistry), 010306 general physics, Neutral particle, 01 natural sciences
Abstract

Using a sample of 106 million psi(3686) decays, psi(3686) -> gamma chi(cJ) (J = 0, 1, 2) and psi(3686) -> gamma chi(cJ), chi(cJ) -> gamma J/psi (J = 1, 2) events are utilized to study incl ...

Published
2020
Full Text
View/download PDF

7. Observation of the Y(4220) and Y(4390) in the process e+e−→ηJ/ψ

Author

Stefano Spataro, Antonio Amoroso, Ilaria BALOSSINO, Meike Kuessner, Yunxuan Song, Alessio Mangoni, Hajime Muramatsu, Xin Shi, Michela Greco, Alexey Zhemchugov, Qiang Zhao, Riccardo Farinelli, Anatoliy Guskov, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Liaoyuan Dong, Francesca De Mori, Onur Bugra Kolcu, Alfons Khoukaz, Yuxiang Zhao, Marco Giovanni Maria Destefanis, Weimin Song, Banzragch Tsednee, Patrik Adlarson, Mikhail Achasov, Johan Messchendorp, Ralf Kliemt, Hongrong Qi, Peirong Li, Xiang Liu, Giulio Mezzadri, Alberto Bortone, Fabio Cossio, and Karin Schoenning

Subjects
Physics, 010308 nuclear & particles physics, 0103 physical sciences, Analytical chemistry, High Energy Physics::Experiment, Nuclear Experiment, 010306 general physics, 01 natural sciences
Abstract

The cross sections of the process e(+)e(-) -> eta J/psi lip at center-of-mass energies (root s) between 3.81 and 4.60 GeV are measured with high precision by using data samples collected with th ...

Published
2020
Full Text
View/download PDF

8. Study of the process e+e−→π0π0J/ψ and neutral charmoniumlike state Zc(3900)0

Author

Stefano Spataro, Peilian Li, Antonio Amoroso, Ilaria BALOSSINO, Meike Kuessner, Hajime Muramatsu, Michela Greco, Alexey Zhemchugov, Riccardo Farinelli, Anatoliy Guskov, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Onur Bugra Kolcu, Alfons Khoukaz, Marco Giovanni Maria Destefanis, Banzragch Tsednee, Patrik Adlarson, Mikhail Achasov, Johan Messchendorp, Ralf Kliemt, Hongrong Qi, Xiang Liu, Alberto Bortone, Fabio Cossio, and Karin Schoenning

Subjects
Physics, 010308 nuclear & particles physics, 0103 physical sciences, Pi, Analytical chemistry, State (functional analysis), 010306 general physics, 7. Clean energy, 01 natural sciences, 3. Good health
Abstract

Cross sections of the process e(+)e(-) -> pi(0)pi(0)J/psi at center-of-mass energies between 3.808 and 4.600 GeV are measured with high precision by using 12.4 fb(-1) of data samples collected w ...

Published
2020
Full Text
View/download PDF

9. Measurement of the Born cross sections for e+e−→Ds+Ds1(2460)−+c.c. and e+e−→Ds*+Ds1(2460)−+c.c

Author

Stefano Spataro, Antonio Amoroso, Ilaria BALOSSINO, Meike Kuessner, Alessio Mangoni, Hongbang Liu, Hajime Muramatsu, Xin Shi, Michela Greco, Alexey Zhemchugov, Riccardo Farinelli, Anatoliy Guskov, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Onur Bugra Kolcu, Nils Huesken, Alfons Khoukaz, Marco Giovanni Maria Destefanis, Banzragch Tsednee, Kamal Saoucha, Patrik Adlarson, Mikhail Achasov, Johan Messchendorp, Ralf Kliemt, Hongrong Qi, Xiang Liu, Giulio Mezzadri, Alberto Bortone, Fabio Cossio, and Karin Schoenning

Subjects
Physics, 010308 nuclear & particles physics, 0103 physical sciences, Analytical chemistry, 010306 general physics, 01 natural sciences
Abstract

The processes e(+)e(-) -> D-s(+) D-s1 (2460)(-) + c.c. and e(+) e(-) -> D-s*(+) D-s1 (2460)(-)+ c.c. are studied for the first time using data samples collected with the BESIII detector at th ...

Published
2020
Full Text
View/download PDF

10. Model-independent determination of the relative strong-phase difference between D0 and D¯0→KS,L0π+π− and its impact on the measurement of the CKM angle γ/ϕ3

Author

Stefano Spataro, Antonio Amoroso, Ilaria BALOSSINO, Meike Kuessner, Alessio Mangoni, Hajime Muramatsu, Michela Greco, Alexey Zhemchugov, Riccardo Farinelli, Yifang Wang, Lei Li, Lia Lavezzi, Jens Sören Lange, Onur Bugra Kolcu, Nils Huesken, Alfons Khoukaz, Marco Giovanni Maria Destefanis, Banzragch Tsednee, Patrik Adlarson, Mikhail Achasov, Johan Messchendorp, Ralf Kliemt, Hongrong Qi, Xiang Liu, Giulio Mezzadri, Fabio Cossio, and Karin Schoenning

Subjects
Phase difference, Physics, Particle physics, Meson, 010308 nuclear & particles physics, Bar (music), High Energy Physics::Phenomenology, 01 natural sciences, 0103 physical sciences, Pi, High Energy Physics::Experiment, Variety (universal algebra), 010306 general physics, Computer Science::Databases
Abstract

Crucial inputs for a variety of CP-violation studies can be determined through the analysis of pairs of quantum-entangled neutral D mesons, which are produced in the decay of the psi(3770) resonanc ...

Published
2020
Full Text
View/download PDF

11. Search for baryon and lepton number violating decays D+→Λ¯(Σ¯0)e+ and D+→Λ(Σ0)e+

Author

Hailong Ma, Ilaria BALOSSINO, Meike Kuessner, Alessio Mangoni, Alexey Zhemchugov, Qiang Zhao, Riccardo Farinelli, Xiaonan Li, Yifang Wang, Liaoyuan Dong, Francesca De Mori, Alfons Khoukaz, Banzragch Tsednee, Johan Messchendorp, Peirong Li, Xiang Liu, and Giulio Mezzadri

Subjects
Physics, Particle physics, 010308 nuclear & particles physics, Branching fraction, Detector, Sigma, Lambda, 01 natural sciences, Lepton number, Baryon, 0103 physical sciences, High Energy Physics::Experiment, Nuclear Experiment, 010306 general physics
Abstract

Using a 2.93 fb(-1) data sample of electron-positron collisions taken with the BESIII detector at a center-of-mass energy of 3.773 GeV, which corresponds to (8296 +/- 31 +/- 64) x 10(3) D+ D- pairs ...

Published
2020
Full Text
View/download PDF

12. Measurement of J/ψ→Ξ(1530)−Ξ¯+ and evidence for the radiative decay Ξ(1530)−→γΞ−

Author

Stefano Spataro, Antonio Amoroso, Ilaria BALOSSINO, Meike Kuessner, Alessio Mangoni, Hongbang Liu, Hajime Muramatsu, Xin Shi, Michela Greco, Alexey Zhemchugov, Riccardo Farinelli, Anatoliy Guskov, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Onur Bugra Kolcu, Nils Huesken, Alfons Khoukaz, Marco Giovanni Maria Destefanis, Vindhyawasini Prasad, Banzragch Tsednee, Patrik Adlarson, Johan Messchendorp, Ralf Kliemt, Hongrong Qi, Giulio Mezzadri, Fabio Cossio, and Karin Schoenning

Subjects
Physics, Nuclear physics, 010308 nuclear & particles physics, Electron–positron annihilation, 0103 physical sciences, Radiative decay, 010306 general physics, 01 natural sciences, Bar (unit)
Abstract

The SU(3)-flavor violating decay J/psi -> Xi(1530)(-) (Xi) over bar (+) + c.c. is studied using (1310.6 +/- 7.0) x 10(6) J/psi events collected with the BESIII detector at BEPCII, and the branch ...

Published
2020
Full Text
View/download PDF

13. First observation of the decay χcJ→Σ+p¯KS0+c.c.(J=0,1,2)

Author

Stefano Spataro, Antonio Amoroso, Ilaria BALOSSINO, Meike Kuessner, Alessio Mangoni, Hongbang Liu, Hajime Muramatsu, Xin Shi, Michela Greco, Alexey Zhemchugov, Qiang Zhao, Riccardo Farinelli, Xiaonan Li, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Liaoyuan Dong, Francesca De Mori, Onur Bugra Kolcu, Alfons Khoukaz, Vindhyawasini Prasad, Banzragch Tsednee, Patrik Adlarson, Johan Messchendorp, Ralf Kliemt, Peirong Li, Xiang Liu, Giulio Mezzadri, Fabio Cossio, and Karin Schoenning

Subjects
Physics, 010308 nuclear & particles physics, visual_art, 0103 physical sciences, visual_art.visual_art_medium, Radiative transfer, Analytical chemistry, Sigma, High Energy Physics::Experiment, Bark, 010306 general physics, 01 natural sciences
Abstract

Using E1 radiative transitions psi(3686) -> gamma chi(cJ) from a sample of (448.1 +/- 2.9) x 10(6) psi(3686) events collected with the BESIII detector, the decays chi(cJ) -> Sigma(+)(p) over ...

Published
2019
Full Text
View/download PDF

14. Measurement of branching fractions of ψ(3686)→ϕη′ , ϕf1(1285) and ϕη(1405)

Author

Stefano Spataro, Antonio Amoroso, Meike Kuessner, Alessio Mangoni, Hongbang Liu, Hajime Muramatsu, Xin Shi, Michela Greco, Alexey Zhemchugov, Qiang Zhao, Riccardo Farinelli, Xiaonan Li, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Liaoyuan Dong, Francesca De Mori, Onur Bugra Kolcu, Alfons Khoukaz, Banzragch Tsednee, Patrik Adlarson, Johan Messchendorp, Ralf Kliemt, Peirong Li, Xiang Liu, Giulio Mezzadri, Fabio Cossio, and Karin Schoenning

Subjects
Nuclear physics, Physics, 010308 nuclear & particles physics, Branching fraction, Electron–positron annihilation, 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Branching (polymer chemistry), 01 natural sciences
Abstract

Using a sample of 448.1 x 10(6) psi(3686) events collected with the BESIII detector, we perform a study of the decay psi(3686) -> phi pi(+)pi(-)eta. The branching fraction of psi(3686) -> phi ...

Published
2019
Full Text
View/download PDF

15. Amplitude analysis of D+→KS0π+π+π−

Author

Stefano Spataro, Antonio Amoroso, Meike Kuessner, Alessio Mangoni, Hongbang Liu, Hajime Muramatsu, Xin Shi, Yu Lu, Michela Greco, Alexey Zhemchugov, Qiang Zhao, Riccardo Farinelli, Xiaonan Li, Anatoliy Guskov, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Liaoyuan Dong, Francesca De Mori, Onur Bugra Kolcu, Alfons Khoukaz, Banzragch Tsednee, Johan Messchendorp, Ralf Kliemt, Peirong Li, Xiang Liu, Giulio Mezzadri, Fabio Cossio, and Karin Schoenning

Subjects
Physics, Amplitude, 010308 nuclear & particles physics, 0103 physical sciences, Detector, Pi, Analytical chemistry, 010306 general physics, 01 natural sciences
Abstract

The decay D+-> K-S(0)pi(+)pi(+)pi(-) is studied with an amplitude analysis using a data set of 2.93 fb(-1) of e(+)e(-) collisions at the psi(3770) peak accumulated by the BESIII detector. Interm ...

Published
2019
Full Text
View/download PDF

16. Improved measurements of the absolute branching fractions of the inclusive decays D+(0)→ϕX

Author

Stefano Spataro, Antonio Amoroso, Hailong Ma, Ilaria BALOSSINO, Meike Kuessner, Alessio Mangoni, Hongbang Liu, Hajime Muramatsu, Xin Shi, Michela Greco, Alexey Zhemchugov, Qiang Zhao, Riccardo Farinelli, Xiaonan Li, Anatoliy Guskov, Jiahui Wei, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Liaoyuan Dong, Francesca De Mori, Onur Bugra Kolcu, Alfons Khoukaz, Vindhyawasini Prasad, Banzragch Tsednee, Patrik Adlarson, Johan Messchendorp, Ralf Kliemt, Peirong Li, Ming-Gang Zhao, Xiang Liu, Giulio Mezzadri, Fabio Cossio, and Karin Schoenning

Subjects
Nuclear physics, Physics, Annihilation, 010308 nuclear & particles physics, 0103 physical sciences, Detector, High Energy Physics::Experiment, 010306 general physics, Branching (polymer chemistry), 01 natural sciences
Abstract

By analyzing 2.93 fb(-1) of e(+)e(-) annihilation data taken at the center-of-mass energy root s = 3.773 GeV with the BESIII detector, we determine the branching fractions of the inclusive decays D ...

Published
2019
Full Text
View/download PDF

17. Measurements of weak decay asymmetries of Λc+→pKs0 , Λπ+ , Σ+π0 , and Σ0π+

Author

Stefano Spataro, Antonio Amoroso, Meike Kuessner, Alessio Mangoni, Hongbang Liu, Hajime Muramatsu, Xin Shi, Michela Greco, Alexey Zhemchugov, Qiang Zhao, Riccardo Farinelli, Xiaonan Li, Anatoliy Guskov, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Liaoyuan Dong, Francesca De Mori, Onur Bugra Kolcu, Alfons Khoukaz, Banzragch Tsednee, Patrik Adlarson, Johan Messchendorp, Ralf Kliemt, Peirong Li, Xiang Liu, Giulio Mezzadri, Fabio Cossio, and Karin Schoenning

Subjects
Nuclear physics, Physics, 010308 nuclear & particles physics, Electron–positron annihilation, Partial wave analysis, 0103 physical sciences, Pi, Sigma, High Energy Physics::Experiment, 010306 general physics, Lambda, 01 natural sciences, Bar (unit)
Abstract

Using e(+)e(-) -> Lambda(+)(c)(Lambda) over bar (-)(c). production from a 567 pb(-1) data sample collected by BESIII at 4.6 GeV, a full angular analysis is carried out simultaneously on the four ...

Published
2019
Full Text
View/download PDF

18. Search for the decay η′→γγη

Author

Stefano Spataro, Antonio Amoroso, Ilaria BALOSSINO, Meike Kuessner, Alessio Mangoni, Hongbang Liu, Hajime Muramatsu, Xin Shi, Michela Greco, Alexey Zhemchugov, Qiang Zhao, Riccardo Farinelli, Xiaonan Li, Anatoliy Guskov, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Liaoyuan Dong, Francesca De Mori, Onur Bugra Kolcu, Alfons Khoukaz, Banzragch Tsednee, Patrik Adlarson, Johan Messchendorp, Ralf Kliemt, Frank Maas, Peirong Li, Xiang Liu, Giulio Mezzadri, Fabio Cossio, and Karin Schoenning

Subjects
Physics, Nuclear physics, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Electron–positron annihilation, 0103 physical sciences, Detector, High Energy Physics::Experiment, Nuclear Experiment, 010306 general physics, 01 natural sciences, Gamma gamma
Abstract

Using a data sample of 1.31 x 10(9) J/psi events collected with the BESIII detector, a search for eta' -> gamma gamma eta via J/psi ->gamma eta' is performed for the first time. No significan ...

Published
2019
Full Text
View/download PDF

19. Observation of ψ(3686)→Ξ(1530)−Ξ¯(1530)+ and Ξ(1530)−Ξ¯+

Author

Stefano Spataro, Antonio Amoroso, Meike Kuessner, Alessio Mangoni, Hongbang Liu, Hajime Muramatsu, Xin Shi, Dr. Xiongfei Wang, Michela Greco, Alexey Zhemchugov, Qiang Zhao, Riccardo Farinelli, Xiaonan Li, Anatoliy Guskov, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Liaoyuan Dong, Francesca De Mori, Onur Bugra Kolcu, Alfons Khoukaz, Vindhyawasini Prasad, Banzragch Tsednee, Patrik Adlarson, Johan Messchendorp, Ralf Kliemt, Frank Maas, Peirong Li, Xiang Liu, Giulio Mezzadri, Fabio Cossio, and Karin Schoenning

Subjects
Physics, Nuclear physics, 010308 nuclear & particles physics, Bar (music), 0103 physical sciences, 010306 general physics, 01 natural sciences
Abstract

Using 448.1 x 10(6) psi(3686) events collected with the BESIII detector at BEPCII, we employ a single-baryon tagging technique to make the first observation of psi(3686) -> Xi(1530)(-)(Xi) over ...

Published
2019
Full Text
View/download PDF

20. Observation of ηc→ωω in J/ψ→γωω

Author

Stefano Spataro, Malte Albrecht, Antonio Amoroso, Meike Kuessner, Alessio Mangoni, Hongbang Liu, Hajime Muramatsu, Xin Shi, Michela Greco, Alexey Zhemchugov, Sanqiang Qu, Riccardo Farinelli, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Onur Bugra Kolcu, Nils Huesken, Alfons Khoukaz, Vindhyawasini Prasad, Banzragch Tsednee, Johan Messchendorp, Ralf Kliemt, Frank Maas, Xiang Liu, Giulio Mezzadri, Fabio Cossio, and Karin Schoenning

Subjects
Physics, Particle physics, Omega
Published
2019
Full Text
View/download PDF

21. Amplitude analysis and branching fraction measurement of D0→K−π+π0π0

Author

Stefano Spataro, Ilaria BALOSSINO, Meike Kuessner, Andrzej Kupsc, Alessio Mangoni, Hongbang Liu, Hajime Muramatsu, Xin Shi, Yu Lu, Michela Greco, Alexey Zhemchugov, Sanqiang Qu, Riccardo Farinelli, Anatoliy Guskov, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Onur Bugra Kolcu, Nils Huesken, Alfons Khoukaz, Banzragch Tsednee, Johan Messchendorp, Ralf Kliemt, Frank Maas, Xiang Liu, Giulio Mezzadri, Tord Johansson, Fabio Cossio, and Karin Schoenning

Subjects
Nuclear physics, Physics, Amplitude, Luminosity (scattering theory), 010308 nuclear & particles physics, Branching fraction, Astrophysics::High Energy Astrophysical Phenomena, 0103 physical sciences, Detector, High Energy Physics::Experiment, State (functional analysis), 010306 general physics, 01 natural sciences
Abstract

Utilizing the dataset corresponding to an integrated luminosity of 2.93 fb(-1) at root s = 3.773 GeV collected by the BESIII detector, we report the first amplitude analysis and branching fraction ...

Published
2019
Full Text
View/download PDF

22. Dalitz plot analysis of the decay ω→π+π−π0

Author

Stefano Spataro, Fritz-Herbert Heinsius, Meike Kuessner, Andrzej Kupsc, Alessio Mangoni, Hongbang Liu, Hajime Muramatsu, Xin Shi, Michela Greco, Alexey Zhemchugov, Sanqiang Qu, Riccardo Farinelli, Anatoliy Guskov, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Onur Bugra Kolcu, Alfons Khoukaz, Vindhyawasini Prasad, Banzragch Tsednee, Johan Messchendorp, Ralf Kliemt, Frank Maas, Xiang Liu, Giulio Mezzadri, Tord Johansson, and Fabio Cossio

Subjects
Physics, Particle physics, 010308 nuclear & particles physics, 0103 physical sciences, Pi, Dalitz plot, High Energy Physics::Experiment, 010306 general physics, 01 natural sciences, Omega, Gamma gamma
Abstract

Using a low-background sample of 2.6 x 10(5) J/psi -> omega eta(omega -> pi(+) pi(-) pi(0), eta -> gamma gamma) events, about 5 times larger statistics than previous experiments, we present a Dalitz plot analysis of the decay omega -> pi(+) pi(-) pi(0). It is found that the Dalitz plot distribution differs from the pure P-wave phase space with a statistical significance of 18.9 sigma. The parameters from the fit to data are in reasonable agreement with those without the cross-channel effect within the dispersive framework, which indicates that the cross-channel effect in omega -> pi(+) pi(-) pi(0) is not significant.

Published
2018
Full Text
View/download PDF

23. Observation of D0(+)→KS0π0(+)η′ and improved measurement of D0→K−π+η′

Author

Stefano Spataro, Fritz-Herbert Heinsius, Hailong Ma, Meike Kuessner, Andrzej Kupsc, Alessio Mangoni, Hongbang Liu, Hajime Muramatsu, Xin Shi, Michela Greco, Alexey Zhemchugov, Qiang Zhao, Riccardo Farinelli, Xiaonan Li, Yifang Wang, Youhua Yang, Lia Lavezzi, Jens Sören Lange, Liaoyuan Dong, Francesca De Mori, Onur Bugra Kolcu, Alfons Khoukaz, Meng Wang, Weimin Song, Banzragch Tsednee, Johan Messchendorp, Ralf Kliemt, Frank Maas, Peirong Li, Xiang Liu, Giulio Mezzadri, Tord Johansson, and Fabio Cossio

Subjects
Physics, Mass energy, 010308 nuclear & particles physics, Branching fraction, Electron–positron annihilation, 0103 physical sciences, Hadron, Pi, Analytical chemistry, 010306 general physics, 01 natural sciences
Abstract

By analyzing an e(+)e(-) data sample corresponding to an integrated luminosity of 2.93 fb(-1) taken at a centerof- mass energy of 3.773 GeV with the BESIII detector, we measure the branching fractions of the Cabibbofavored hadronic decays D-0 -> K- pi' eta', D-0 -> K-s(0)pi(0)eta', which are determined to be (6.43 +/- 0.15(stat)+/- 0.31(syst)) x 10(-3), (2.52 +/- 0.22(stat) +/- 0.15(syst)) x 10(-3,) and (1.90 +/- 0.17(stat) +/- 0.13(syst)) x 10(-3), respectively. The precision of the branching fraction of D-0 -> K- pi(+) eta' is significantly improved, and the processes D-0 -> K-S(0)pi(0)eta' and D+ -> K-S(0) pi(+)eta' are observed for the first time.

Published
2018
Full Text
View/download PDF

24. Amplitude analysis of the KSKS system produced in radiative J/ψ decays

Author

Stefano Spataro, Fritz-Herbert Heinsius, Meike Kuessner, Andrzej Kupsc, Hongbang Liu, Hajime Muramatsu, Michela Greco, Alexey Zhemchugov, Qiang Zhao, Riccardo Farinelli, Orhan CAKIR, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Onur Bugra Kolcu, Alfons Khoukaz, Banzragch Tsednee, Johan Messchendorp, Ralf Kliemt, Frank Maas, Xiang Liu, Manuel Dionisio Da Rocha Rolo, Giulio Mezzadri, and Tord Johansson

Subjects
Physics, S system, Nuclear physics, Amplitude, 010308 nuclear & particles physics, 0103 physical sciences, Radiative transfer, 010306 general physics, 01 natural sciences
Published
2018
Full Text
View/download PDF

25. Search for the rare decay of ψ(3686)→Λc+p¯e+e−+c.c. at BESIII

Author

Stefano Spataro, Fritz-Herbert Heinsius, Meike Kuessner, Andrzej Kupsc, Alessio Mangoni, Hongbang Liu, Hajime Muramatsu, Xin Shi, Michela Greco, Ulrich Wiedner, Alexey Zhemchugov, Riccardo Farinelli, Orhan CAKIR, Yifang Wang, Lia Lavezzi, Jens Sören Lange, Onur Bugra Kolcu, Alfons Khoukaz, Banzragch Tsednee, Johan Messchendorp, Ralf Kliemt, Xiang Liu, Manuel Dionisio Da Rocha Rolo, Giulio Mezzadri, Tord Johansson, Fabio Cossio, and Yang Zhang

Subjects
Physics, 010308 nuclear & particles physics, Branching fraction, Flavor-changing neutral current, 0103 physical sciences, Analytical chemistry, High Energy Physics::Experiment, 010306 general physics, Lambda, 01 natural sciences, Standard Model
Abstract

Based on a data sample of (448.1 +/- 2.9) x 10(6)Psi(3686) decays collected with the BESIII experiment, a search for the flavor changing neutral current transition Psi(3686) -> Lambda(+)(c) pe(+) e(-) + c.c. is performed for the first time. No signal candidates are observed and the upper limit on the branching fraction of Psi(3686) -> Lambda(+)(c) pe(+) e(-) is determined to be 1.7 x 10(-6) at the 90% confidence level. The result is consistent with expectations from the standard model, and no evidence for new physics is found.

Published
2018
Full Text
View/download PDF

26. Improved measurements of χcJ→Σ+Σ¯− and Σ0Σ¯0 decays

Author

Stefano Spataro, Fritz-Herbert Heinsius, SERKANT ALİ ÇETİN, Ronald Poling, Meike Kuessner, Hongbang Liu, Dayong Wang, Michela Greco, Ulrich Wiedner, Fenfen An, Alexey Zhemchugov, Qiang Zhao, Xiang Zhou, Riccardo Farinelli, Xiaonan Li, Jake Bennett, Orhan CAKIR, Yifang Wang, Youhua Yang, Lia Lavezzi, Jens Sören Lange, Liaoyuan Dong, Francesca De Mori, Onur Bugra Kolcu, Alfons Khoukaz, Meng Wang, Weimin Song, Chang-Zheng Yuan, Vindhyawasini Prasad, Banzragch Tsednee, Johan Messchendorp, Ralf Kliemt, Frank Maas, Peirong Li, Xiang Liu, Manuel Dionisio Da Rocha Rolo, Giulio Mezzadri, Tord Johansson, and Yang Zhang

Subjects
Physics, Particle physics, Overline, 010308 nuclear & particles physics, 0103 physical sciences, Sigma, 010306 general physics, 01 natural sciences
Published
2018
Full Text
View/download PDF

27. Measurement of the absolute branching fraction of Ds0*(2317)±→π0Ds±

Author

Stefano Spataro, Fritz-Herbert Heinsius, SERKANT ALİ ÇETİN, Ronald Poling, Meike Kuessner, Andrzej Kupsc, Hongbang Liu, Dayong Wang, Hajime Muramatsu, Michela Greco, Ulrich Wiedner, Fenfen An, Alexey Zhemchugov, Qiang Zhao, Xiang Zhou, Riccardo Farinelli, Xiaonan Li, Jake Bennett, Orhan CAKIR, Yifang Wang, Youhua Yang, Lia Lavezzi, Jens Sören Lange, Liaoyuan Dong, Francesca De Mori, Onur Bugra Kolcu, Alfons Khoukaz, Meng Wang, Weimin Song, Chang-Zheng Yuan, Vindhyawasini Prasad, Banzragch Tsednee, Johan Messchendorp, Ralf Kliemt, Frank Maas, Peirong Li, Xiang Liu, Manuel Dionisio Da Rocha Rolo, Giulio Mezzadri, and Tord Johansson

Subjects
Physics, 010308 nuclear & particles physics, Branching fraction, 0103 physical sciences, Analytical chemistry, 010306 general physics, 01 natural sciences
Abstract

The process e(+)e(-) -> D*D-+(s)*(s0) (2317)(-) + c.c. is observed for the first time with the data sample of 567 pb(-1) collected with the BESIII detector operating at the BEPCII collider at a center-of-mass energy root s = 4.6 GeV. The statistical significance of the D*(s0) (2317)(+/-) signal is 5.8 sigma and the mass is measured to be (2318.3 +/- 1.2 +/- 1.2) MeV/c(2). The absolute branching fraction B(D*(s0) (2317)(+/-) -> pi D-0(s)+/-) is measured as 1.00(-0.14)(+0.00) (stat)(-0.14)(+0.00) (syst) for the first time. The uncertainties are statistical and systematic, respectively.

Published
2018
Full Text
View/download PDF

28. Observation of χc2→η′η′ and χc0,2→ηη′

Author

Fritz-Herbert Heinsius, Ronald Poling, Hongbang Liu, Hajime Muramatsu, ALPEREN YÜNCÜ, Michela Greco, Ulrich Wiedner, Fenfen An, Alexey Zhemchugov, Qiang Zhao, Riccardo Farinelli, Bo Zheng, Jake Bennett, Orhan CAKIR, Yifang Wang, Jens Sören Lange, Liaoyuan Dong, Onur Bugra Kolcu, Alfons Khoukaz, Chang-Zheng Yuan, Banzragch Tsednee, Xiaolin Kang, Johan Messchendorp, Ralf Kliemt, Frank Maas, Xiang Liu, Manuel Dionisio Da Rocha Rolo, Giulio Mezzadri, and Tord Johansson

Subjects
Physics, Particle physics, High Energy Physics::Experiment, Nuclear Experiment, Pseudoscalar meson
Abstract

Using a sample of 448.1 x 10(6) Psi(3686) events collected with the BESIII detector in 2009 and 2012, we study the decays chi(c0,2) -> eta 'eta ' and eta eta '. The decays chi(c2) -> eta 'eta ', chi(c0) -> eta eta ' and chi(c2) -> eta eta ' are observed for the first time with statistical significances of 9.6 sigma, 13.4 sigma and 7.5 sigma, respectively. The branching fractions are determined to be B(chi(c0) -> eta 'eta ') = (2.19 +/- 0.03 +/- 0.14) x 10(-3), B(chi(c2) -> eta 'eta ') = (4.76 +/- 0.56 +/- 0.38) x 10(-5), B(chi(c0) -> eta eta ') = (8.92 +/- 0.84 +/- 0.65) x 10(-5) and B(chi(c2) -> eta eta ') = (2.27 +/- 0.43 +/- 0.25) x 10(-5), where the first uncertainties are statistical and the second are systematic. The precision for the measurement of B(chi(c0) -> eta 'eta ') thorn is significantly improved compared to previous measurements. Based on the measured branching fractions, the role played by the doubly and singly Okubo-Zweig-Iizuka disconnected transition amplitudes for chi(c0,2) decays into pseudoscalar meson pairs can be clarified.

Published
2017
Full Text
View/download PDF

29. Branching fraction measurement of J/ψ→KSKL and search for J/ψ→KSKS

Author

Fritz-Herbert Heinsius, SERKANT ALİ ÇETİN, Ronald Poling, Meike Kuessner, Hongbang Liu, Dayong Wang, Hajime Muramatsu, ALPEREN YÜNCÜ, Michela Greco, Ulrich Wiedner, Fenfen An, Alexey Zhemchugov, Qiang Zhao, Xiang Zhou, Riccardo Farinelli, Xiaonan Li, Jake Bennett, Orhan CAKIR, Yifang Wang, Youhua Yang, Lia Lavezzi, Jens Sören Lange, Liaoyuan Dong, Francesca De Mori, Onur Bugra Kolcu, Alfons Khoukaz, Meng Wang, Weimin Song, Chang-Zheng Yuan, Banzragch Tsednee, Johan Messchendorp, Ralf Kliemt, Frank Maas, Peirong Li, Xiang Liu, Manuel Dionisio Da Rocha Rolo, Giulio Mezzadri, and Tord Johansson

Subjects
Physics, Particle physics, 010308 nuclear & particles physics, law, Branching fraction, Electron–positron annihilation, 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Collider, 01 natural sciences, law.invention
Abstract

Using a sample of 1.31 x 10(9) J/Psi events collected with the BESIII detector at the BEPCII collider, we study the decays of J/Psi -> KSKL and KSKS. The branching fraction of J/Psi -> KSKL is determined to be B(J/Psi -> KSKL) = (1.93 +/- 0.01 (stat) +/- 0.05 (syst)) x 10(-4), which significantly improves on previous measurements. No clear signal is observed for the J/Psi -> KSKS process, and the upper limit at the 95% confidence level for its branching fraction is determined to be B(J/Psi -> KSKS) < 1.4 x 10(-8), which improves on the previous searches by 2 orders in magnitude and reaches the order of the Einstein-Podolsky-Rosen expectation.

Published
2017
Full Text
View/download PDF

30. HADRON PHYSICS AT COSY

Author

Alfons Khoukaz

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Meson production, Meson, Scattering, Hyperon, General Physics and Astronomy, Astronomy and Astrophysics, Atomic and Molecular Physics, and Optics, Synchrotron, law.invention, Nuclear physics, law, Hadron physics, Symmetry breaking, Focus (optics), Nuclear Experiment
Abstract

One major focus of the physics studied at the COoler SYnchrotron COSY of the Forschungszentrum Jülich is the production of mesons and hyperons in the hadron-hadron scattering with the aim to investigate relevant production processes, interactions of the participating particles as well as symmetries and symmetry breaking. Due to the excellent experimental conditions at COSY also single- and double-polarization measurements can be performed with high reaction rates. This contribution gives an overview about the physics program which is currently under investigation at the three big COSY installations ANKE, COSY-TOF and WASA-at-COSY.

Published
2009
Full Text
View/download PDF

31. Study of the pd→→n{pp}s charge-exchange reaction using a polarised deuterium target

Author

Gou, B., Mchedlishvili, D., Bagdasarian, Z., Barsov, S., Carbonell, J., Chiladze, D., Dymov, S., Engels, R., Gaisser, M., Gebel, R., Grigoryev, K., Hartmann, M., Kacharava, A., Alfons Khoukaz, Kulessa, P., Kulikov, A., Lehrach, A., Li, Z., Lomidze, N., Lorentz, B., Macharashvili, G., Merzliakov, S., Mielke, M., Mikirtychyants, M., Mikirtychyants, S., Nioradze, M., Ohm, H., Prasuhn, D., Rathmann, F., Serdyuk, V., Seyfarth, H., Shmakova, V., Ströher, H., Tabidze, M., Trusov, S., Tsirkov, D., Yu. Uzikov, Yu. Valdau, Wang, T., Weidemann, C., Wilkin, C., and Yuan, X.

Subjects
Nuclear Theory, Physics::Accelerator Physics, Polarisation effects, Nuclear Experiment, lcsh:Physics, lcsh:QC1-999, Deuteron charge exchange
Abstract

The vector and tensor analysing powers, Ay and Ayy, of the pd→→n{pp}s charge-exchange reaction have been measured at a beam energy of 600 MeV at the COSY-ANKE facility by using an unpolarised proton beam incident on an internal storage cell target filled with polarised deuterium gas. The low energy recoiling protons were measured in a pair of silicon tracking telescopes placed on either side of the target. Putting a cut of 3 MeV on the diproton excitation energy ensured that the two protons were dominantly in the S01 state, here denoted by {pp}s. The polarisation of the deuterium gas was established through measurements in parallel of proton–deuteron elastic scattering. By analysing events where both protons entered the same telescope, the charge-exchange reaction was measured for momentum transfers q≥160 MeV/c. These data provide a good continuation of the earlier results at q≤140 MeV/c obtained with a polarised deuteron beam. They are also consistent with impulse approximation predictions with little sign evident for any modifications due to multiple scatterings. These successful results confirm that the ANKE deuteron charge-exchange programme can be extended to much higher energies with a polarised deuterium target than can be achieved with a polarised deuteron beam. Keywords: Deuteron charge exchange, Polarisation effects

Published
2015

32. Determination of the ${\eta }^{\prime }$-Proton Scattering Length in Free Space

Author

Czerwiński, E., Moskal, P., Ritman, J., Sefzick, T., Smyrski, J., Täschner, A., Wolke, M., Zieliński, M., Silarski, M., Bass, S. D., Grzonka, D., Kamys, B., Alfons Khoukaz, Klaja, J., Krzemień, W., and Oelert, W.

Subjects
ddc:550, Physics::Accelerator Physics, High Energy Physics::Experiment, Nuclear Experiment, Astrophysics::Galaxy Astrophysics
Abstract

Taking advantage of both the high mass resolution of the COSY-11 detector and the high energy resolution of the low-emittance proton beam of the cooler synchrotron COSY, we determine the excitation function for the pp→ppη′ reaction close to threshold. Combining these data with previous results, we extract the scattering length for the η′-proton potential in free space to be Re(apη′)=0±0.43 fm and Im(apη′)=0.37+0.40−0.16 fm.

Published
2014
Full Text
View/download PDF

33. Excitation of the Delta(1232) isobar in deuteron charge exchange on hydrogen at 1.6, 1.8, and 2.3 GeV

Author

Mchedlishvili, D., Barsov, S., Goslawski, P., Hartmann, M., Imambekov, O., Kacharava, A., Kamerdzhiev, V., Keshelashvili, I., Alfons Khoukaz, Komarov, V., Kulessa, P., Kulikov, A., Carbonell, J., Lehrach, A., Lomidze, N., Lorentz, B., Macharashvili, G., Maier, R., Merzliakov, S., Mielke, M., Mikirtychyants, M., Mikirtytchiants, Sergey, Nioradze, M., Chiladze, D., Ohm, H., Papenbrock, M., Prasuhn, D., Rathmann, F., Serdyuk, V., Seyfarth, H., Stein, H. J., Steffens, E., Stockhorst, H., Stroeher, Hans, Dymov, S., Tabidze, M., Trusov, S., Uzikov, Yu, Valdau, Yu, Wilkin, C., Dzyuba, A., Engels, Ralf W., Gebel, R., Glagolev, V., Grigoryev, K., Institut de Physique Nucléaire d'Orsay (IPNO), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Nuclear Theory (nucl-th), Nuclear Theory, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], FOS: Physical sciences, ddc:530, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract

The charge-exchange break-up of polarised deuterons pol{d}p -> {pp}n, where the final {pp} diproton system has a very low excitation energy and hence is mainly in the 1S0 state, is a powerful tool to probe the spin-flip terms in the proton-neutron charge-exchange scattering. Recent measurements with the ANKE spectrometer at the COSY storage ring at 1.6, 1.8, and 2.27 GeV have extended these studies into the pion-production regime in order to investigate the mechanism for the excitation of the Delta(1232) isobar in the pol{d}p -> {pp}X reaction. Values of the differential cross section and two deuteron tensor analysing powers, A_{xx} and A_{yy}, have been extracted in terms of the momentum transfer to the diproton or the invariant mass Mx of the unobserved system X. The unpolarised cross section in the high Mx region is well described in a model that includes only direct excitation of the Delta isobar through undistorted one pion exchange. However, the cross section is grossly underestimated for low Mx, even when Delta excitation in the projectile deuteron is included in the calculation. Furthermore, direct Delta production through one pion exchange only reproduces the angular dependence of the difference between the two tensor analysing powers., 7 pages with 6 figures

Published
2013
Full Text
View/download PDF

38. Differential cross section and analysing power of the pp-> pp_s pi^0 reaction at 353 MeV

Author

Tsirkov, D., Azaryan, T., Kacharava, A., Alfons Khoukaz, Komarov, V., Kulessa, P., Kulikov, A., Kurbatov, V., Lensky, V., Lorentz, B., Macharashvili, G., Mchedlishvili, David, Baru, V., Mielke, M., Mikirtytchiants, S., Merzliakov, S., Nioradze, M., Ohm, H., Papenbrock, M., Rathmann, F., Serdyuk, V., Shmakova, V., Ströher, H., Chiladze, D., Uzikov, Yu, Valdau, Yu, Wilkin, C., Dymov, S., Dzyuba, A., Gebel, R., Goslawski, P., Hanhart, C., and Hartmann, M.

Subjects
exclusive reaction [p p], ANKE, Nuclear Theory, partial wave [amplitude analysis], dihadron, 0.353 GeV, Juelich COSY PS, angular dependence, polarized beam [p], differential cross section, +2p+pi0%22">p p --> 2p pi0, analyzing power, ddc:530, hadroproduction [pi0], Nuclear Experiment, experimental results
Abstract

In order to establish links between p-wave pion production in nucleon-nucleon collisions and low energy three-nucleon scattering, an extensive programme of experiments on pion production is currently underway at COSY-ANKE. The final proton pair is detected at very low excitation energy, leading to an S-wave diproton, denoted here as {pp}_s. We now report on measurements of the differential cross section and analysing power of the pol{p}p->{pp}_s pi^0$ reaction at 353 MeV. Both observables can be described in terms of s- and d-wave pion production and, by using the phase information from elastic pp scattering, unique solutions can be obtained for the corresponding amplitudes. This information is vital for the partial wave decomposition of the corresponding pn->{pp}_s pi^- reaction and hence for the extraction of the p-wave terms., Comment: The interested reader is advised to study also the paper on pi minus production by S.Dymov et al., which has also been submitted to the arXiv

Published
2012
Full Text
View/download PDF

40. Energy dependence of the pp -> K(+)n Sigma(+) reaction close to threshold

Author

Valdau, Y., Barsov, S., Buscher, M., Chiladze, D., Dymov, S., Dzyuba, A., Hartmann, M., Kacharava, A., Keshelashvili, I., Alfons Khoukaz, Koptev, V., Kulessa, P., Merzliakov, S., Mielke, M., Mikirtychiants, S., Nekipelov, M., Ohm, H., Papenbrock, M., Rathmann, F., Serdyuk, V., Stroher, H., Trusov, S., and Wilkin, C.

Abstract

Production of the Sigma(+) hyperon through the pp -> K(+)n Sigma(+) reaction has been investigated at four energies close to threshold, 1.826, 1.920, 1.958, and 2.020 GeV. At low energies, correlated K+pi(+) pairs can only originate from Sigma(+) production so their measurement allows the total cross section for the reaction to be determined. The results obtained are completely consistent with the values extracted from the study of the K+-proton correlation spectra obtained in the same experiment. These spectra, as well as the inclusive K+ momentum distributions, also provide conservative upper limits on Sigma(+) production rates. The measurements show a Sigma(+) production cross section that varies roughly like phase space, and, in particular, none of the three experimental approaches used supports the anomalously high, near-threshold pp -> K(+)n Sigma(+) total cross section previously reported [T. Rozek et al., Phys. Lett. B 643, 251 (2006)].

Published
2010

41. Invariant mass distributions for the pp to p p eta reaction at Q=10 MeV

Author

Moskal, P., Czyzykiewicz, R., Krzemien, W., Oelert, W., Ritman, J., Sefzick, T., Siemaszko, M., Silarski, M., Smyrski, J., Täschner, A., Wolke, M., Wüstner, P., Czerwinksi, E., Zdebik, J., Zielinski, M., Zipper, W., Gil, D., Grzonka, D., Jarczyk, L., Kamys, B., Alfons Khoukaz, Klaja, J., and Klaja, P.

Subjects
channel cross section, hadroproduction [eta], partial wave [amplitude analysis], Nuclear Theory, FOS: Physical sciences, Juelich COSY PS, +2p+eta%22">p p --> 2p eta, (p eta) [mass spectrum], threshold, inelastic scattering [p p], Physics::Accelerator Physics, ddc:530, Nuclear Experiment (nucl-ex), Nuclear Experiment, (2p) [mass spectrum]
Abstract

Proton-proton and proton-eta invariant mass distributions and the total cross section for the pp to pp eta reaction have been determined near the threshold at an excess energy of Q=10 MeV. The experiment has been conducted using the COSY-11 detector setup and the cooler synchrotron COSY. The determined invariant mass spectra reveal significant enhancements in the region of low proton-proton relative momenta, similarly as observed previously at higher excess energies of Q=15.5 MeV and Q= 40MeV., Comment: 6 pages, 3 figures, submitted to Eur.Phys. J. A

Published
2009
Full Text
View/download PDF

42. Near threshold production of the pseudoscalar mesons at the COSY-11 facility

Author

Moskal, P., Czyzykiewicz, R., Alfons Khoukaz, Kilian, K., Klaja, P., Oelert, W., Piskor-Ignatowicz, B., Przerwa, J., Rejdych, B., Ritman, J., Sefzick, T., Siemaszko, M., Adam, H. -H, Silarski, M., Smyrski, J., Täschner, A., Wolke, M., Wüstner, P., Zielinski, M., Zipper, W., Budzanowski, A., Czerwinski, E., Gil, D., Grzonka, D., Janusz, M., Jarczyk, L., and Kamys, B.

Published
2008

43. Precision study of the eta-3He system using the d+p->3He+eta reaction

Author

Mersmann, T., Alfons Khoukaz, Maeda, Y., Mielke, M., Mikirtychiants, S., Ohm, H., Papenbrock, M., Prasuhn, D., Rathmann, F., Rausmann, T., Schleichert, R., Serdyuk, V., Büscher, M., Stein, H. -J, Ströher, H., Täschner, A., Valdau, Yu, Wilkin, C., Wronska, A., Chiladze, D., Dymov, S., Hartmann, M., Hejny, V., Kacharava, A., Keshelashvili, I., and Kulessa, P.

Subjects
hadroproduction [eta], experimental results [magnetic spectrometer], missing-mass [mass spectrum], partial wave, +helium-3+eta%22">deuteron p --> helium-3 eta, Juelich COSY PS, energy dependence [channel cross section], exclusive reaction [p deuteron], angular dependence, ddc:550, threshold, momentum dependence [asymmetry], scattering length [eta nucleus], Nuclear Experiment, nuclide [helium]
Abstract

The differential and total cross sections for the d+p->3He+eta reaction have been measured in a high precision high statistics COSY-ANKE experiment near threshold using a continuous beam energy ramp up to an excess energy Q of 11.3 MeV with essentially 100% acceptance. The kinematics allowed the mean value of Q to be determined to about 9 keV. Evidence is found for the effects of higher partial waves for Q>4 MeV. The very rapid rise of the total cross section to its maximum value within 0.5 MeV of threshold implies a very large eta-3He scattering length and hence the presence of a quasi-bound state extremely close to threshold., Comment: 4 pages, 4 figures, 1 table, submitted to Phys. Rev. Lett

Published
2007
Full Text
View/download PDF

44. New results on the pd to 3He eta production from threshold up to Q = 40 MeV

Author

Adam, H. H., Alfons Khoukaz, Moskal, P., Piskor-Ignatowicz, C., Przerwa, J., Smyrski, J., Grzonka, D., Kilian, K., Oelert, W., Sefzick, T., Winter, P., Wolke, M., Lang, N., Wüstner, P., Budzanowski, A., Rozek, T., Siemaszko, M., Zipper, W., Lister, T., Santo, R., Steltenkamp, S., Czyzykiewicz, R., Janusz, M., Jarczyk, L., and Kamys, B.

Subjects
hadroproduction [eta], quasi-bound states, Nuclear Theory, Cracow 2004/06/04 [talk], Juelich COSY PS, final-state interaction, angular distribution [eta], near threshold meson production, nuclear reaction [p deuteron], final state interaction, threshold, +helium-3+eta%22">p deuteron --> helium-3 eta, High Energy Physics::Experiment, ddc:530, energy dependence [cross section], Nuclear Experiment, effect [resonance], experimental results
Abstract

Measurements on the eta meson production in proton-deuteron collisions have been performed using the COSY-11 facility at COSY (Julich). Here we present preliminary results on total and differential cross sections for the pd -> He-3 eta reaction at five excess energies between Q = 5.1 and Q = 40.6 MeV. The obtained angular distributions for the emitted eta mesons in the center of mass system expose a transition from an almost isotropic emission to a highly anisotropic distribution. The extracted total cross sections support a strong eta-He-3 final state interaction and will be compared with model predictions.

Published
2005
Full Text
View/download PDF

45. Energy dependence of the Lambda/Sigma0 production cross section ratio in p-p interactions

Author

Kowina, P., Adam, H. -H, Klaja, P., Moskal, P., Oelert, W., Piskor-Ignatowicz, C., Przerwa, J., Rozek, T., Santo, R., Sefzick, T., Siemaszko, M., Smyrski, J., Budzanowski, A., Strzalkowski, A., Täschner, A., Winter, P., Wolke, M., Wüstner, P., Zipper, W., Czyzykiewicz, R., Grzonka, D., Janusz, M., Jarczyk, L., Kamys, B., Alfons Khoukaz, and Kilian, K.

Subjects
Physics, Meson, Hadron, FOS: Physical sciences, Elementary particle, Lambda baryon, Spectral line, Sigma baryon, Baryon, Atomic physics, Nuclear Experiment (nucl-ex), Nuclear Experiment, Order of magnitude
Abstract

Measurements of the near threshold Lambda and Sigma0 production via the pp-->pK+Lambda/Sigma0 reaction at COSY--11 have shown that the Lambda/Sigma0 cross section ratio exceeds the value at high excess energies Q>=300 MeV by an order of magnitude. For a better understanding additional data have been taken between 13 MeV and 60 MeV excess energy. Within the first 20 MeV excess energy a strong decrease of the cross section ratio is observed, with a less steep decrease in the higher excess energy range. A description of the data with a parametrisation including p-Y final state interactions suggests a much smaller p-Sigma0 FSI compared to the p-Lambda system., 6 pages, 3 figures, Presented at X. International Conference On Hadron Spectroscopy (Hadron 2003), Aschaffenburg, Germany, 31 Aug - 6 Sep 2003

Published
2004
Full Text
View/download PDF

46. Near-threshold production of omega mesons in the pn -> d omega reaction

Author

Barsov, S., Lehmann, I., Schleichert, R., Wilkin, C., Buscher, M., Dymov, S., Golubeva, Y., Hartmann, M., Hejny, V., Kacharava, A., Keshelashvili, I., Alfons Khoukaz, Komarov, V., Kondratyuk, La, Lang, N., Macharashvili, G., Mersmann, T., Merzliakov, S., Mussgiller, A., Nioradze, M., Petrus, A., Stroher, H., Uzikov, Y., and Zalikhanov, B.

Subjects
experimental results [magnetic spectrometer], target [deuterium], spectator [p], +deuteron+omega%28783%29%22">p n --> deuteron omega(783), ddc:530, momentum [deuteron], inelastic scattering [p n], Juelich COSY PS, Nuclear Experiment, hadroproduction [omega(783)], momentum transfer [channel cross section]
Abstract

The first measurement of the p n -> d omega total cross section has been achieved at mean excess energies of Q = 28 and 57 MeV by using a deuterium cluster-jet target. The momentum of the fast deuteron was measured in the ANKE spectrometer at COSY-Juelich and that of the slow "spectator" proton p(sp) from the p d -> p(sp) d omega reaction in a silicon telescope placed close to the target. The cross sections lie above those measured for p p -> p p omega but seem to be below theoretical predictions., Comment: 7 pages, 8 figures; second approach to describe the background has been added; results changed insignificantly, EPJ in press

Published
2003
Full Text
View/download PDF

48. Associated strangeness production in pp collisions near threshold

Author

Winter, P., Adam, H. -H, Klaja, P., Kowina, P., Moskal, P., Oelert, W., Piskor-Ignatowicz, C., Przerwa, J., Rozek, T., Santo, R., Sefzick, T., Siemaszko, M., Budzanowski, A., Smyrski, J., Strzalkowski, A., Täschner, A., Wolke, M., Wüstner, P., Zipper, W., Czyzykiewicz, R., Grzonka, D., Janusz, M., Jarczyk, L., Kamys, B., Alfons Khoukaz, and Kilian, K.

Subjects
Physics, Nuclear physics, Cross section (physics), Near threshold, Meson production, Phase space, Scalar (mathematics), Mass spectrum, Strangeness production, FOS: Physical sciences, State (functional analysis), Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract

Motivated by the ongoing discussion concerning the nature of the scalar resonances f0(980) and a0(980), the COSY-11 collaboration has taken exclusive data on the pp->ppK+K- reaction near the production threshold. A first total cross section sigma=(1.80+-0.27+0.28-0.35)nb for the excess energy Q=17 MeV has been determined. In contrary to the eta, omega and eta' single meson production studies which clearly show the strong pp final state interaction (FSI), the cross section values obtained at COSY-11 and DISTO can be both described by a fit with a four-body phase space including the proton-proton final state interaction as well as with one-meson exchange calculations neglecting FSI effects. Therefore, one might think about a compensation of the strong pp interaction through a pK- FSI effect or an additional degree of freedom caused by the four-body final state. In the latter case, strong FSI effects can be expected at Q-values very close to the K+K- production threshold. Such a motivation triggered -- in combination with the investigation of the kaon-Antikaon interaction being relevant to the structure of the f0(980) -- further measurements at the excess energies Q=10 and Q=28 MeV at COSY-11., 5 pages, 4 figures, Presented at X. International Conference On Hadron Spectroscopy (Hadron 2003), Aschaffenburg, Germany, 31 Aug - 6 Sep 2003

Published
2003
Full Text
View/download PDF

49. Proton-proton collisions at production thresholds

Author

Moskal, P., Adam, H. -H, Budzanowski, A., Gazonka, D., Jarczyk, L., Alfons Khoukaz, Kilian, K., Köhler, M., Kowina, P., Lang, N., Lister, T., Oelert, W., Quentmeier, C., Santo, R., Schepers, G., Sefzick, T., Sewerin, S., Siemaszko, M., Smyrski, J., Sokołowski, M., Strzałkowski, A., Wolke, M., Wüstner, P., and Zipper, W.

Subjects
Nuclear Theory, jądro atomu, FOS: Physical sciences, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), Nuclear Experiment, proton
Abstract

Recent results obtained by the COSY-11 collaboration concerning the production of eta and eta' mesons in the pp --> pp Meson reaction are presented. A comparison of the production amplitude for the pi(0), eta and eta' mesons at the same phase space volume allows to conclude that the proton-eta' interaction is in the order of, or smaller than, the proton-pi(0) one. A total cross section determined in a preliminary analysis of the data of elementary kaon and antikaon production via the pp-->ppK(+)K(-) reaction measured at excess energy of Q = 17 MeV is reported., Talk given at the International Workshop MESON'2000, Cracow, Poland, 19-23 May 2000, 8pp. To be published in Acta Phys. Pol. B

Published
2000

50. Two-Pion Production in ProtonProton Collisions near Threshold

Author

Kjell Fransson and Alfons Khoukaz

Subjects
Physics, Proton, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, Nuclear physics, Cross section (physics), Pion, Amplitude, Isospin, Atomic physics, Nuclear Experiment, Mathematical Physics, Beam (structure), Storage ring, Excitation
Abstract

Two-pion production reactions in proton-proton collisions have been studied using the PROMICE/WASA detector and an internal cluster gas-jet target at the CELSIUS storage ring in Uppsala. The total cross sections for the pp → ppπ+π-, pp → ppπ0π0 and the pp → pnπ0π+ reactions are presented at beam energies ranging from 650 to 775 MeV. An isospin analysis of the amplitudes involved in these three reactions indicates that the excitation of the N*(1440) followed by direct two pion emission can be the most important amplitude when allowed. However, large contributions from other production mechanisms must also be prevalent to explain the large pp → pnπ0π+ cross section. The data are compared to an extensive model including non-resonant as well as resonant production via N* and Δ excitation.

Published
2003
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results