https://doi.org/10.1140/epjc/s10052-021-09425-w
Regular Article - Theoretical Physics
The nature of X(3872) from high-multiplicity pp collisions
1
Theoretical Particle Physics Laboratory (LPTP), Institute of Physics, EPFL, 1015, Lausanne, Switzerland
2
Instituto Galego de Física de Altas Enerxías-IGFAE, Universidade de Santiago de Compostela, 15782, Santiago de Compostela, Galicia, Spain
3
European Centre for Theoretical Studies in Nuclear Physics and related Areas (ECT*) and Fondazione Bruno Kessler, Villazzano, 38123, Trento, Italy
4
INFN Sezione di Genova, via Dodecaneso 33, 16146, Genoa, Italy
5
INFN Sezione di Roma, Piazzale Aldo Moro 5, 00185, Rome, Italy
6
Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 5, 00185, Rome, Italy
7
Dipartimento di Scienze Matematiche e Informatiche, Scienze Fisiche e Scienze della Terra, Universitá degli Studi di Messina, Viale Ferdinando Stagno d’Alcontres 31, 98166, Messina, Italy
a
antonio.polosa@roma1.infn.it
Received:
3
June
2021
Accepted:
5
July
2021
Published online:
30
July
2021
The structure of exotic resonances that do not trivially fit the usual quark model expectations has been a matter of intense scientific debate during the last two decades. A possible way of estimating the size of these states is to study their behavior when immersed in QCD matter. Recently, LHCb has measured the relative abundance of the exotic 
over the ordinary 
. We use the comover interaction model to study the yield of a compact . To confirm the reliability of the model in high-multiplicity pp collisions, we describe the suppression of excited over ground 
states. With this at hand, we show that the size of the compact would be slightly larger than that of the . If the is instead assumed to be a meson molecule of large size, we argue that its evolution in QCD matter should be described via a coalescence model, as suggested by data on deuteron production. We show that the predictions of this model for the are in contrast with data.
© The Author(s) 2021
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