https://doi.org/10.1140/epja/s10050-022-00723-9
Regular Article - Theoretical Physics
Experimental constraints on the properties of 
states
1
Department of Physics, Swansea University, Singleton Park, SA2 8PP, Swansea, UK
2
Department of Physics and Astronomy, University of Pittsburgh, 15260, Pittsburgh, PA, USA
Received:
19
January
2022
Accepted:
3
April
2022
Published online:
16
April
2022
Using new experimental data on photoproduction and 
decays, we derive constraints on the properties of the LHCb states. We conclude that 
, 
and 
can be described as 
, 
and 
molecules, but that 
does not fit into the same picture. Based on the apparent absence of additional partner states, and the striking disparity between 
and 
decays, we conclude that has 
quantum numbers. Using heavy-quark symmetry we predict large experimental signals for states in 
, 
, and 
. We also argue that current experimental data on photoproduction is almost at the level of sensitivity required to observe states.
© The Author(s) 2022
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