Search results for "nuclear emulsion"
showing 7 items of 7 documents
First muography of Stromboli volcano
2019
AbstractMuography consists in observing the differential absorption of muons – elementary particles produced through cosmic-ray interactions in the Earth atmosphere – going through the volcano and can attain a spatial resolution of tens of meters. We present here the first experiment of nuclear emulsion muography at the Stromboli volcano. Muons have been recorded during a period of five months by a detector of 0.96 m2 area. The emulsion films were prepared at the Gran Sasso underground laboratory and were analyzed at Napoli, Salerno and Tokyo scanning laboratories. Our results highlight a significant low-density zone at the summit of the volcano with density contrast of 30–40% with respect …
The scattering of 38 MeV α-particles by C, N, 0, F and Kr nuclei
1960
This paper describes observations by a photographic method on the angular distributions of 38 MeV α-particles scattered by light nuclei. Elastically and inelastically scattered particles were distinguished by their range in nuclear emulsion. The observed distributions are compared with the general predictions of the nuclear optical model, of direct interaction theories,and of the inelastic diffraction theory of Blair. In teraction radii are deduced from the angular distributions.
Fragmentation of accelerated 2.1 GeV/nucleon12C,14N and16O Ions in nuclear emulsion
1975
The inelastic-interaction mean free path and fragmentation parameters in nuclear emulsion of accelerated 2.1 GeV/nucleon12C,14N and16O have been determined. The discrimination of the targets has been achieved with a new method. The global results obtained for the three ions have been compared with theM-group of the cosmic radiation.
Charged charmed particle lifetime
1984
Abstract We present the lifetime values obtained for D ± and Λ c + , photoproduced in nuclear emulsion in the WA58 experiment. In photohadronic interactions, pairs of charmed particles are produced. Out of 20 charged charmed particles used for lifetime evaluation, 17 have their charmed partner seen emulsion, being then essentially free from any background. The values of the lifetime are τ D ± = (3.91 −1.25 +2.35 ) × 10 −13 s, τ Λ c + = (2.22 −0.75 +1.34 ) × 10 −13 s.
Measurement of charmed-particle lifetimes and decay branching ratios
1987
The lifetimes of charmed hadrons photoproduced in nuclear emulsion have been computed from a practically background-free sample of 44 neutral particle decays and 42 charged-particle decays including 27D±, 11Λc+, 1Ds+ and 3 ambiguous decays. The values obtained are τ(D0, bar D0) = (3.6-0.8+1.2 ± 0.7) 10-13 s, τ(D±) = (5.0-1.0+1.5 ± 1.9) 10-13 s, τ(Λc+) = = (2.3-0.6+0.9 ± 0.4) 10-13 s. Branching ratios of various decay topologies were also obtained.
Search for νμ(νe) ↔ ντ oscillations with a detector based on a emulsion-silicon target
1996
We discuss the performance of a next generation νμ(νe)↔ ντ oscillation experiment, based on a target consisting of a sandwich of nuclear emulsion layers and silicon detectors. The target would be followed by a full spectrometer for energy-momentum measurement and particle identification. A τ-enriched sample is selected in terms of vertex and kinematical criteria using the electronic spectrometer, with very high efficiency, while at the same time reducing the load of background events to be scanned by up to two orders of magnitude. Events fulfilling the selection criteria are very efficiently located and scanned in the emulsion, thanks to the very good resolution allowed by the silicon track…
Status of J-PARC E07: Systematic study of double strangeness nuclei with hybrid emulsion method
2019
J-PARC E07 is the most complex emulsion experiment to date investigating double hypernuclei with a hybrid emulsion method. This experiment aims to detect 104 Ξ− stop events, ten times more events than the past experiments. Thus, an unequivocal identification of several new double hypernuclei is expected. The beam exposure has been completed at the K1.8 beam line of the J-PARC hadron facility in June 2017. The photographic development of all emulsion sheets has also been completed in February 2018. The emulsion sheets are presently being analyzed with dedicated optical microscopes. Current statistics is comparable to that of E373 and so far 10 events of 3-vertices topology have been detected…