@article{b41664c318df4e88a7c7f45ca3702666,
title = "Observation of an exotic narrow doubly charmed tetraquark",
abstract = "Conventional, hadronic matter consists of baryons and mesons made of three quarks and a quark–antiquark pair, respectively1,2. Here, we report the observation of a hadronic state containing four quarks in the Large Hadron Collider beauty experiment. This so-called tetraquark contains two charm quarks, a u¯¯¯ and a d¯¯¯ quark. This exotic state has a mass of approximately 3,875 MeV and manifests as a narrow peak in the mass spectrum of D0D0π+ mesons just below the D*+D0 mass threshold. The near-threshold mass together with the narrow width reveals the resonance nature of the state.",
author = "R. Aaij and B. Adeva and M. Adinolfi and Z. Ajaltouni and S. Akar and J. Albrecht and F. Alessio and {De Bruyn}, K. and L. Dufour and M. Mulder and Onderwater, {C. J. G.} and A. Pellegrino and S. Tolk and {van Veghel}, M. and {LHCb Collaboration}",
note = "Funding Information: This Letter is dedicated to the memory of our dear colleague Simon Eidelman, whose friendship, deep physics insights and contributions to improving the quality of our papers were greatly appreciated and will be missed. We express our gratitude to our colleagues in the CERN accelerator departments for the excellent performance of the LHC. We thank the technical and administrative staff at the LHCb institutes. We acknowledge support from CERN and from the following national agencies: CAPES, CNPq, FAPERJ and FINEP (Brazil); MOST and NSFC (China); CNRS/IN2P3 (France); BMBF, DFG and MPG (Germany); INFN (Italy); NWO (the Netherlands); MNiSW and NCN (Poland); MEN/IFA (Romania); MSHE (Russia); MICINN (Spain); SNSF and SER (Switzerland); NASU (Ukraine); STFC (United Kindgom); DOE NP and NSF (United States). We acknowledge the computing resources that are provided by CERN, IN2P3 (France), KIT and DESY (Germany), INFN (Italy), SURF (the Netherlands), PIC (Spain), GridPP (United Kingdom), RRCKI and Yandex LLC (Russia), CSCS (Switzerland), IFIN-HH (Romania), CBPF (Brazil), PL-GRID (Poland) and NERSC (United States). We are indebted to the communities behind the multiple open-source software packages on which we depend. Individual groups or members have received support from ARC and ARDC (Australia); AvH Foundation (Germany); EPLANET, Marie Sk{\l}odowska-Curie Actions and ERC (European Union); A*MIDEX, ANR, IPhU and Labex P2IO, and R{\'e}gion Auvergne-Rh{\^o}ne-Alpes (France); Key Research Program of Frontier Sciences of CAS, CAS PIFI, CAS CCEPP, Fundamental Research Funds for the Central Universities, and Sci. & Tech. Program of Guangzhou (China); RFBR, RSF and Yandex LLC (Russia); GVA, XuntaGal and GENCAT (Spain); the Leverhulme Trust, the Royal Society and UKRI (United Kingdom). Funding Information: This Letter is dedicated to the memory of our dear colleague Simon Eidelman, whose friendship, deep physics insights and contributions to improving the quality of our papers were greatly appreciated and will be missed. We express our gratitude to our colleagues in the CERN accelerator departments for the excellent performance of the LHC. We thank the technical and administrative staff at the LHCb institutes. We acknowledge support from CERN and from the following national agencies: CAPES, CNPq, FAPERJ and FINEP (Brazil); MOST and NSFC (China); CNRS/IN2P3 (France); BMBF, DFG and MPG (Germany); INFN (Italy); NWO (the Netherlands); MNiSW and NCN (Poland); MEN/IFA (Romania); MSHE (Russia); MICINN (Spain); SNSF and SER (Switzerland); NASU (Ukraine); STFC (United Kindgom); DOE NP and NSF (United States). We acknowledge the computing resources that are provided by CERN, IN2P3 (France), KIT and DESY (Germany), INFN (Italy), SURF (the Netherlands), PIC (Spain), GridPP (United Kingdom), RRCKI and Yandex LLC (Russia), CSCS (Switzerland), IFIN-HH (Romania), CBPF (Brazil), PL-GRID (Poland) and NERSC (United States). We are indebted to the communities behind the multiple open-source software packages on which we depend. Individual groups or members have received support from ARC and ARDC (Australia); AvH Foundation (Germany); EPLANET, Marie Sk{\l}odowska-Curie Actions and ERC (European Union); A*MIDEX, ANR, IPhU and Labex P2IO, and R{\'e}gion Auvergne-Rh{\^o}ne-Alpes (France); Key Research Program of Frontier Sciences of CAS, CAS PIFI, CAS CCEPP, Fundamental Research Funds for the Central Universities, and Sci. & Tech. Program of Guangzhou (China); RFBR, RSF and Yandex LLC (Russia); GVA, XuntaGal and GENCAT (Spain); the Leverhulme Trust, the Royal Society and UKRI (United Kingdom). Publisher Copyright: {\textcopyright} 2022, The Author(s).",
year = "2022",
month = jul,
doi = "10.1038/s41567-022-01614-y",
language = "English",
volume = "18",
pages = "751--754",
journal = "Nature Physics",
issn = "1745-2481",
publisher = "Nature Publishing Group",
number = "7",
}