Abstract
An amplitude analysis of the decay Λ 0 b → D 0 pπ − is performed in the part of the phase space containing resonances in the D 0 p channel. The study is based on a data sample corresponding to an integrated luminosity of 3.0 fb−1 of pp collisions recorded by the LHCb experiment. The spectrum of excited Λ + c states that decay into D 0 p is studied. The masses, widths and quantum numbers of the Λc(2880)+ and Λc(2940)+ resonances are measured. The constraints on the spin and parity for the Λc(2940)+ state are obtained for the first time. A near-threshold enhancement in the D 0 p amplitude is investigated and found to be consistent with a new resonance, denoted the Λc(2860)+, of spin 3/2 and positive parity.
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ArXiv ePrint: 1701.07873
C. Baesso, M. Cruz Torres, C. Göbel are , associated to Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
J. He, X. Lyu, D. Vieira, Y. Zhang, Y. Zheng are associated to Center for High Energy Physics, Tsinghua University, Beijing, China
L. Sun is associated to Center for High Energy Physics, Tsinghua University, Beijing, China
Y. Xie, H. Yin, J. Yu are associated to Center for High Energy Physics, Tsinghua University, Beijing, China
D. A. Milanes, I. A. Monroy, J. A. Rodriguez Lopez are associated to LPNHE, Université Pierre et Marie Curie, Université Paris Diderot, CNRS/IN2P3, Paris, France
O. Grünberg, M. Heß, H. Viemann, R. Waldi are associated to Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany
T. Likhomanenko, A. Malinin, O. Morgunova, A. Nogay, A. Petrov, V. Shevchenko are associated to Institute of Theoretical and Experimental Physics (ITEP), Moscow, Russia
L. M. Garcia Martin, F. Martinez Vidal, A. Oyanguren, C. Remon Alepuz, P. Ruiz Valls, C. Sanchez Mayordomo are associated to ICCUB, Universitat de Barcelona, Barcelona, Spain
C. J. G. Onderwater is associated to Nikhef National Institute for Subatomic Physics, Amsterdam, The Netherlands
Deceased (J. Blouw, P. Rodriguez Perez)
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The LHCb collaboration., Aaij, R., Adeva, B. et al. Study of the D 0 p amplitude in Λ 0 b → D 0 pπ − decays. J. High Energ. Phys. 2017, 30 (2017). https://doi.org/10.1007/JHEP05(2017)030
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DOI: https://doi.org/10.1007/JHEP05(2017)030