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arXiv · 2109.01038

Observation of an exotic narrow doubly charmed tetraquark

LHCb collaboration·R. Aaij·A. S. W. Abdelmotteleb·C. Abellán Beteta·F. J. Abudinen Gallego·T. Ackernley·B. Adeva·M. Adinolfi·H. Afsharnia·C. Agapopoulou·C. A. Aidala·S. Aiola·Z. Ajaltouni·S. Akar·J. Albrecht·F. Alessio·M. Alexander·A. Alfonso Albero·Z. Aliouche·G. Alkhazov·P. Alvarez Cartelle·S. Amato·J. L. Amey·Y. Amhis·L. An·L. Anderlini·A. Andreianov·M. Andreotti·F. Archilli·A. Artamonov·M. Artuso·K. Arzymatov·E. Aslanides·M. Atzeni·B. Audurier·S. Bachmann·M. Bachmayer·J. J. Back·P. Baladron Rodriguez·V. Balagura·W. Baldini·J. Baptista Leite·M. Barbetti·R. J. Barlow·S. Barsuk·W. Barter·M. Bartolini·F. Baryshnikov·J. M. Basels·S. Bashir·G. Bassi·B. Batsukh·A. Battig·A. Bay·A. Beck·M. Becker·F. Bedeschi·I. Bediaga·A. Beiter·V. Belavin·S. Belin·V. Bellee·K. Belous·I. Belov·I. Belyaev·G. Bencivenni·E. Ben-Haim·A. Berezhnoy·R. Bernet·D. Berninghoff·H. C. Bernstein·C. Bertella·A. Bertolin·C. Betancourt·F. Betti·Ia. Bezshyiko·S. Bhasin·J. Bhom·L. Bian·M. S. Bieker·S. Bifani·P. Billoir·M. Birch·F. C. R. Bishop·A. Bitadze·A. Bizzeti·M. Bjørn·M. P. Blago·T. Blake·F. Blanc·S. Blusk·D. Bobulska·J. A. Boelhauve·O. Boente Garcia·T. Boettcher·A. Boldyrev·A. Bondar·N. Bondar·S. Borghi·M. Borisyak
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Abstract

Conventional hadronic matter consists of baryons and mesons made of three quarks and quark-antiquark pairs, respectively. The observation of a new type of hadronic state, a doubly charmed tetraquark containing two charm quarks, an anti-$u$ and an anti-$d$ quark, is reported using data collected by the LHCb experiment at the Large Hadron Collider. This exotic state with a mass of about 3875 MeV$/c^2$ manifests itself as a narrow peak in the mass spectrum of $D^0D^0\pi^+$ mesons just below the $D^{*+}D^0$ mass threshold. The near threshold mass together with a strikingly narrow width reveals the resonance nature of the state.

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LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb, C. Abellán Beteta, F. J. Abudinen Gallego, T. Ackernley, B. Adeva, M. Adinolfi, H. Afsharnia, C. Agapopoulou, C. A. Aidala, S. Aiola, Z. Ajaltouni, S. Akar, J. Albrecht, F. Alessio, M. Alexander, A. Alfonso Albero, Z. Aliouche, G. Alkhazov, P. Alvarez Cartelle, S. Amato, J. L. Amey, Y. Amhis, L. An, L. Anderlini, A. Andreianov, M. Andreotti, F. Archilli, A. Artamonov, M. Artuso, K. Arzymatov, E. Aslanides, M. Atzeni, B. Audurier, S. Bachmann, M. Bachmayer, J. J. Back, P. Baladron Rodriguez, V. Balagura, W. Baldini, J. Baptista Leite, M. Barbetti, R. J. Barlow, S. Barsuk, W. Barter, M. Bartolini, F. Baryshnikov, J. M. Basels, S. Bashir, G. Bassi, B. Batsukh, A. Battig, A. Bay, A. Beck, M. Becker, F. Bedeschi, I. Bediaga, A. Beiter, V. Belavin, S. Belin, V. Bellee, K. Belous, I. Belov, I. Belyaev, G. Bencivenni, E. Ben-Haim, A. Berezhnoy, R. Bernet, D. Berninghoff, H. C. Bernstein, C. Bertella, A. Bertolin, C. Betancourt, F. Betti, Ia. Bezshyiko, S. Bhasin, J. Bhom, L. Bian, M. S. Bieker, S. Bifani, P. Billoir, M. Birch, F. C. R. Bishop, A. Bitadze, A. Bizzeti, M. Bjørn, M. P. Blago, T. Blake, F. Blanc, S. Blusk, D. Bobulska, J. A. Boelhauve, O. Boente Garcia, T. Boettcher, A. Boldyrev, A. Bondar, N. Bondar, S. Borghi, M. Borisyak. 2021-09-02. Observation of an exotic narrow doubly charmed tetraquark. https://doi.org/10.1038/s41567-022-01614-y

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