4 papers
The Compact X and Z and their Invisible Molecular Partners
A. Carducci, B. Grinstein, D. Germani +1
We propose a model explaining the strong isospin violations observed in X(3872) decays. The X is assumed to be a compact isosinglet tetraquark and its charged partners to form an i…
Tetraquarks in the Born-Oppenheimer approximation
Davide Germani, Benjamin Grinstein, Antonio Davide Polosa
The conventional loosely bound molecule interpretation of the is not compatible with the recent LHCb experimental measurement of the ratio of branching fractions $\mathca…
ALP contribution to the Strong CP problem
Victor Enguita, Belen Gavela, Benjamin Grinstein +1
We compute the one-loop contribution to the -parameter of an axion-like particle (ALP) with CP-odd derivative couplings. Its contribution to the neutron electric dipole mome…
Radiative decays of X(3872) discriminate between the molecular and compact interpretations
B. Grinstein, L. Maiani, A. D. Polosa
Radiative decays X --> psi(1S) + gamma and X --> psi(2S) + gamma might be expected to have a ratio of branching fractions following the phase space volumes ratio. However data sugg…