About the Authors

Silvio a Beccara

Affiliation LISC, Bruno Kessler Foundation, Trento, Italy

Tatjana Škrbić

Affiliation ECT*, Bruno Kessler Foundation, Trento, Italy

Roberto Covino

Affiliations Physics Department, University of Trento, Trento, Italy, INFN, Gruppo Collegato di Trento, Trento, Italy

Cristian Micheletti

Affiliation SISSA and CNR-IOM Democritos, Trieste, Italy

Pietro Faccioli

faccioli@science.unitn.it

Affiliations Physics Department, University of Trento, Trento, Italy, INFN, Gruppo Collegato di Trento, Trento, Italy

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: CM PF. Performed the experiments: SaB TS RC. Analyzed the data: TS RC CM PF. Wrote the paper: CM PF.