Topical issue on underground nuclear astrophysics and solar neutrinos: Impact on astrophysics, solar and neutrino physics Gianpaolo Bellini, Carlo Broggini and Alessandra Guglielmetti Eur. Phys. J. A (2016) 52: 88 Published online: 19 April 2016 [DOI: https://doi.org/10.1140/epja/i2016-16088-y]