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Neutrons induced by cosmic-ray muons are a significant background for underground experiments studying neutrino oscillations, neutrino-less double beta decay, dark matter and other rare-event signals. The Daya Bay Reactor Antineutrino experiment consists of 8 antineutrino detectors (AD) placed in three experimental halls at different baselines from six nuclear reactors. Each AD contains 20 tons of Gd-doped liquid scintillator, serving as the main target for antineutrinos interacting via the inverse beta-decay (IBD) reaction. The data from Daya Bay allows to make a competitive measurement of neutron production by cosmogenic muons at depths of 250, 265 and 860 meters-water-equivalent.

Cosmic ray muon radiography is a novel technique for imaging the internal structure of volcanoes. It exploits the capability of high energy muons from cosmic-rays to penetrate large thicknesses of rock, in order to obtain a density map of volcanic edifices and trying to guess informations on the variation in the rock density distribution, like those expected from dense lava conduits, or low density magma supply paths. Nuclear emulsions are tracking detectors well suited to be employed in this context since they have an excellent angular resolution (few mrad), they are cheap, compact and robust, easily transportable on a mountain, able to work in harsh environments, and do not require power supply. The main drawback in the usage of such passive detectors is the time consuming procedure of data acquisition since a large detector area (of the order of 1 m²) is needed to collect a sufficient statistics of muons. In the last decade, the development of faster automatic scanning systems made it possible to overcome this difficulty. The first successful result in the field of muon radiography with nuclear emulsions was obtained by a Japanese group that observed in 2007 the conduit structure of the active Mt. Asama volcano. Since 2010, other volcanoes have been explored with the same technique: Mt. Unzen in Japan in 2010, Stromboli volcano in Italy in 2011, and Mt. Teide in Tenerife in 2012. An overview of the Stromboli emulsion detector design will be given, followed by the preliminary results obtained. Next plans for future projects will be also considered.