Near-threshold D D ¯ \[ \mathrm{D}\overline{\mathrm{D}} \] spectroscopy and observation of a new charmonium state

• Published in: The journal of high energy physics 2019-07, Vol.2019 (7), p.1-23
• Main Authors: P Alvarez Cartelle, Amato, S, Artamonov, A, Audurier, B, Balagura, V, Batozskaya, V, Battig, A, Bay, A, Belous, K, Bertolin, A, Bhasin, S, Blusk, S, Boettcher, T, Bozzi, C, Cadeddu, S, Chatzikonstantinidis, G, Chekalina, V, Ciezarek, G, Comerma-Montells, A, Couturier, B, M Cruz Torres, Dalseno, J, De Capua, S, Dean, C T, Demmer, M, Dey, B, Dziewiecki, M, Eisenhardt, S, Filippov, S, Fini, R A, Gorelov, I V, Greim, R, Hadavizadeh, T, Haefeli, G, Hicheur, A, R Hidalgo Charman, Ibis, P, Inglessi, A, Jashal, B K, Ketel, T, Khanji, B, Koliiev, S, Kvaratskheliya, T, Longstaff, I, Lusiani, A, Mackowiak, P, Malygina, H, Marangotto, D, D Martinez Santos, Materok, M, McNulty, R, Meinert, N, Mitzel, D S, Moise, R D, Morello, G, Morris, A B, Müller, J, Nandi, A, Nieswand, S, Osborn, J D, Pellegrino, A, Penso, G, Pietrzyk, B, Polci, F, Ponce, S, Pugatch, V, Pullen, H, Qian, W, Rangel, M S, Ratnikov, F, Roehrken, M, Roth, J D, J Ruiz Vidal, Saitta, B, Schindler, H, Schmidt, B, Serra, N, Skiba, I, Soares, M, Stagni, F, Stefkova, S, Steinkamp, O, Stemmle, S, Straumann, U, Tilley, M J, Tisserand, V, Usachov, A, Vagnoni, V, E van Herwijnen, C Vázquez Sierra, Veronesi, M, Viana Barbosa, J V, Vilasis-Cardona, X, Vorobyev, A, Walsh, J, Wang, M, Websdale, D, Q Xu, Zhang, W C, Zhelezov, A
• Format: Article
• Language: English
• Subjects: Arrays; High energy physics; Luminosity; Particle collisions; Uncertainty
• ISSN: 1029-8479
• DOI: 10.1007/JHEP07(2019)035

Using proton-proton collision data, corresponding to an integrated luminosity of 9 fb−1, collected with the LHCb detector between 2011 and 2018, a new narrow charmonium state, the X(3842) resonance, is observed in the decay modes X3842→D0D¯0\[ \mathrm{X}(3842)\to {D}^0{\overline{D}}^0 \] and X(3842) → D+D−. The mass and the natural width of this state are measured to bemX3842=3842.71±0.16±0.12MeV/c2,ΓX3842=2.79±0.51±0.35MeV,\[ \begin{array}{l}{m}_{X(3842)}=3842.71\pm 0.16\pm 0.12\ MeV/{c}^2,\hfill \\ {}{\varGamma}_{X(3842)}=2.79\pm 0.51\pm 0.35\ MeV,\hfill \end{array} \]where the first uncertainty is statistical and the second is systematic. The observed mass and narrow natural width suggest the interpretation of the new state as the unobserved (spin-3 ψ3 13D3) charmonium state.In addition, prompt hadroproduction of the ψ(3770) and χ2(3930) states is observed for the first time, and the parameters of these states are measured to bemψ3770=3778.1±0.7±0.6MeV/c2,mχ23930=3921.9±0.6±0.2MeV/c2,Γχ23930=36.6±1.9±0.9MeV,\[ \begin{array}{l}{m}_{\psi (3770)}=3778.1\pm 0.7\pm 0.6\ MeV/{c}^2,\hfill \\ {}{m}_{\chi_2(3930)}=3921.9\pm 0.6\pm 0.2\ MeV/{c}^2,\hfill \\ {}{\varGamma}_{\chi_2(3930)}=36.6 \pm 1.9 \pm 0.9\ MeV,\hfill \end{array} \]where the first uncertainty is statistical and the second is systematic.