arXiv subjects

K. Piscicchia

Publications and source records attributed to K. Piscicchia.

60 records · Page 4Linked to original sources

arXiv2014

Testing the Pauli Exclusion Principle for electrons at LNGS

High-precision experiments have been done to test the Pauli exclusion principle (PEP) for electrons by searching for anomalous $K$-series X-rays from a Cu target supplied with electric current. With the highest sensitivity, the VIP (VIolation of Pauli Exclusion Principle) experiment set an upper limit at the level of $10^{-29}$ for the probability that an external electron captured by a Cu atom can make the transition from the 2$p$ state to a 1$s$ state already occupied by two electrons. In a follow-up experiment at Gran Sasso, we aim to increase the sensitivity by two orders of magnitude. We show proofs that the proposed improvement factor is realistic based on the results from recent performance tests of the detectors we did at Laboratori Nazionali di Frascati (LNF).

quant-ph↗

arXiv2013

Characterization of a scintillating fibers read by MPPC detectors trigger prototype for the AMADEUS experiment

Multi-Pixel Photon Counters (MPPC) consist of hundreds of micro silicon Avalanche PhotoDiodes (APD) working in Geiger mode. The high gain and the low noise, typical of these devices, together with their good performance in magnetic field, make them ideal readout detectors for scintillating fibers as trigger detectors in particle and nuclear physics experiments like AMADEUS, where such detectors are planned to be used to trigger on charged kaon pairs. In order to investigate the detection efficiency of such a system, a prototype setup consisting of 32, 1 mm diameter scintillating fibers, arranged in two double layers of 16 fibers each, and read out by 64 MPPCs with an ad-hoc built readout electronics, was tested at the piM-1 line of the Paul Scherrer Institute (PSI) in Villigen, Switzerland. The detection efficiency and the trigger capability were measured on a beam containing protons, electrons, muons and pions with a momentum of 440 MeV/c. The measured average efficiency for protons for a double layer of scintillating fibers (96.9 +/-1.2%) represents a guarantee of the good performance of this system as a trigger for the AMADEUS experiment.

physics.ins-det↗

arXiv2013

Low energy kaon-nuclei interaction studies through the Σ^0π^0 channel with the KLOE detector

The AMADEUS experiment aims to perform precision studies in the sector of low-energy kaon-nuclei interaction at the DAΦNE collider at LNF-INFN, implementing a dedicated setup in the central region of the KLOE detector. As a first step towards the AMADEUS realization the existing KLOE data (runs from 2002 to 2005) were analysed using the detector itself as an active target. K^- nuclear interactions in the gas filling the KLOE drift chamber (Helium 90% and Isobutane 10%) and the drift chamber entrance wall (mainly Carbon) were explored. Starting point was the reconstruction of the Λ(1116) trough its decay into a proton and a pion (BR = 63.9 \pm 0.5%). Taking advantage of the good performances of the KLOE calorimeter in detecting photons we then focused on the investigation of the Λ(1405), through its decay into Σ^0π^0. The details of the Σ^0 π^0 analysis and preliminary results are presented.

nucl-ex↗

arXiv2013

Study of $Σ^+π^-$ Invariant Mass spectrum with the KLOE detector; preliminary results and possible hints for $Σ^+n$ internal conversion

The AMADEUS collaboration has the goal to perform unprecedented measurements in the field of the low-energy charged kaons-nuclei interactions, by implementing the existing KLOE detector with a dedicated setup in the inner region. As a preliminary step towards the realization, the AMADEUS team has analyzed the existent 2002-2005 KLOE data, studying the processes resulting from the negative kaons nuclear absorption in the entrance wall of the KLOE Drift Chamber (containing mostly carbon) and in the gas filling it, mostly helium. Processes containing Lambda-p and Lambda-d in the final state were looked for, together with the search for the Lambda(1405) going in both the neutral and the charged Sigma-pi channels. These analyses produced unique results, proving the possibility to obtain, for the first time, invariant mass spectra of the Lambda(1405) for all the possible decay channels. This was possible thanks to the unique features of the KLOE detector, including the excellent photon detection of its calorimeter. In addition to these results, other interesting effects like the Sigma->Lambda internal conversion could be investigated. Preliminary results on the Sigma+pi- decay channel and on the Sigma->Lambda internal conversion will be presented.

nucl-ex↗

arXiv2013

Kaon-nuclei interaction studies at low energies (the AMADEUS project)

The AMADEUS experiment aims to perform dedicated precision studies in the sector of low-energy kaon-nuclei interaction at the DAΦNE collider at LNF-INFN. In particular the experiment plans to perform measurements of the debated deeply bound kaonic nuclear states (by stopping kaons in cryogenic gaseous targets 3He and 4He) to explore the nature of the Λ(1405) in nuclear environment and to measure the cross section of K- on light nuclei, for K- momentum lower than 100 MeV/c. The AMADEUS dedicated setup will be installed in the central region of the KLOE detector.

nucl-ex↗

arXiv2011

Kaonic 3He and 4He X-ray measurements in SIDDHARTA

The strong-interaction shift of kaonic 3He and 4He 2p states was measured using gaseous targets for the first time in the SIDDHARTA experiment. The determined shift of kaonic 4He is much smaller than the values obtained in the experiments performed in 70's and 80's. Thus, the problems in kaonic helium (the "kaonic helium puzzle") was definitely solved by our measurements. The first observation of the kaonic 3He X-rays was also achieved. The shift both of kaonic 3He and 4He was found to be as small as a few eV.

nucl-ex↗