The NEMO project: A status report Taiuti, M.; Aiello, S.; Ameli, F. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
01/2011, Letnik:
626
Journal Article
Recenzirano
The latest results and the activities towards the construction of a km
3 Cherenkov neutrino detector carried out by the NEMO Collaboration are described. Long-term exploration of a 3500
m deep-sea ...site close to the Sicilian coast has shown that it is optimal for the installation of the detector. The NEMO Phase-1 project has validated several technologies proposed for the construction of the km
3 detector on a test site at 2000
m depth. The new infrastructure on the candidate Capo Passero site set up as part of the Phase-2 project will provide the possibility to test detector components at 3500
m depth.
The NEMO Collaboration installed and operated an underwater detector including prototypes of the critical elements of a possible underwater km
3 neutrino telescope: a four-floor tower (called ...Mini-Tower) and a Junction Box. The detector was developed to test some of the main systems of the km
3 detector, including the data transmission, the power distribution, the timing calibration and the acoustic positioning systems as well as to verify the capabilities of a single tridimensional detection structure to reconstruct muon tracks. We present results of the analysis of the data collected with the NEMO Mini-Tower. The position of photomultiplier tubes (PMTs) is determined through the acoustic position system. Signals detected with PMTs are used to reconstruct the tracks of atmospheric muons. The angular distribution of atmospheric muons was measured and results compared to Monte Carlo simulations.
In March 2013, the NEMO Phase 2 tower has been successfully installed in the Capo Passero site, at a depth of 3500 m and 80 km off from the southern coast of Sicily. The unfurled tower is 450 m high; ...it is composed of 8 mechanical floors, for a total amount of 32 PMTs and various instruments for environmental measurements. The tower positioning is achieved by an acoustic system. The tower is continuously acquiring and transmitting all the measured signals to shore. Data reduction is completely performed in the Portopalo shore station by a dedicated computing facility connected to the persistent storage system at LNS, in Catania. Results from the last 9 months of acquisition will be presented. In particular, the analyzed optical rates, showing stable and low baseline values, are compatible with the contribution mainly of super(40)K light emission, with a small percentage of light bursts due to bioluminescence. These features reveal the optimal nature of the Capo Passero abyssal site to host a km super(3) -sized Neutrino Telescope.
Type 2-high severe asthma (T2-SA) is often associated with several comorbidities. To this extent, the coexistence of T2-SA and bronchiectasis (BE) is considered an emerging phenotype.
We performed a ...prospective observational multicentre study, including T2-SA patients. Chest HRCT confirmed the presence of BE. Data on exacerbations, pulmonary function, Asthma Control Test (ACT), chronic mucus hypersecretion (CMH), chronic rhinosinusitis (CRS), oral corticosteroid (OCS) dosage, eosinophils in peripheral blood and FeNO were recorded. The Bhalla score was used for radiological assessment of T2-SA+BE patients and the Bronchiectasis Severity Index (BSI) was calculated.
A total of 113 patients (mean age 55 ± 11 years, 59.3% female) were enrolled. Co-presence of BE was confirmed in 50/113 (44.2%) patients who identified the T2-SA+BE group. CRS and CRSwNP were more prevalent in T2-SA+BE vs T2-SA respectively, 42/50 (84%) vs 37/63 (58.7%), p = 0.004 and 27/50 (54%) vs 27/63 (42.9%), p = 0.0165. Furthermore, T2-SA+BE patients reported more CMH compared to T2-SA 29/50 (58%) vs 15/63 (23.8%), p = 0.0004, were more frequently on chronic OCSs intake 28/50 (56%) vs 22/63 (34.9%), p = 0.0357 and experienced more exacerbations/year 10 (4-12) vs 6 (4-12), p = 0.0487. In a multivariate logistic regression model, the presence of CRS, CMH and daily OCS intake were associated with BE presence with a 78% (95% CI: 69-88) accuracy. Median Bhalla score was 18.3 (16-20) (Mild radiological severity). Median BSI was 6 (4-8) and only 6/50 (12%) had a BSI score ≥9. Significant inverse linear relationship between BSI and ACT (r = -0.6095, p < 0.0001), FEV
% (r = -0.3297, p = 0.0353) and FEV
mL (r = -0.4339, p = 0.0046) were found.
Type 2 inflammation could have a causative role in BE development. Chest HRCT is mandatory when a diagnosis of T2-SA is made, especially in presence of CRS, CMH and chronic OCS intake. Early BE detection may be crucial to improve T2-SA patients' outcomes.
The first prototype of a photo-detection unit of the future KM3NeT neutrino telescope has been deployed in the deep waters of the Mediterranean Sea. This digital optical module has a novel design ...with a very large photocathode area segmented by the use of 31 three inch photomultiplier tubes. It has been integrated in the ANTARES detector for in-situ testing and validation. This paper reports on the first months of data taking and rate measurements. The analysis results highlight the capabilities of the new module design in terms of background suppression and signal recognition. The directionality of the optical module enables the recognition of multiple Cherenkov photons from the same
40
K decay and the localisation of bioluminescent activity in the neighbourhood. The single unit can cleanly identify atmospheric muons and provide sensitivity to the muon arrival directions.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The NEutrino Mediterranean Observatory-Submarine Network 1 (NEMO-SN1) seafloor observatory is located in the central Mediterranean Sea, Western Ionian Sea, off Eastern Sicily (Southern Italy) at ...2100-m water depth, 25 km from the harbor of the city of Catania. It is a prototype of a cabled deep-sea multiparameter observatory and the first one operating with real-time data transmission in Europe since 2005. NEMO-SN1 is also the first-established node of the European Multidisciplinary Seafloor Observatory (EMSO), one of the incoming European large-scale research infrastructures included in the Roadmap of the European Strategy Forum on Research Infrastructures (ESFRI) since 2006. EMSO will specifically address long-term monitoring of environmental processes related to marine ecosystems, climate change, and geohazards. NEMO-SN1 has been deployed and developed over the last decade thanks to Italian funding and to the European Commission (EC) project European Seas Observatory NETwork-Network of Excellence (ESONET-NoE, 2007-2011) that funded the Listening to the Deep Ocean-Demonstration Mission (LIDO-DM) and a technological interoperability test (http://www.esonet-emso.org). NEMO-SN1 is performing geophysical and environmental long-term monitoring by acquiring seismological, geomagnetic, gravimetric, accelerometric, physico-oceanographic, hydroacoustic, and bioacoustic measurements. Scientific objectives include studying seismic signals, tsunami generation and warnings, its hydroacoustic precursors, and ambient noise characterization in terms of marine mammal sounds, environmental and anthropogenic sources. NEMO-SN1 is also an important test site for the construction of the Kilometre-Cube Underwater Neutrino Telescope (KM3NeT), another large-scale research infrastructure included in the ESFRI Roadmap based on a large volume neutrino telescope. The description of the observatory and its most recent implementations is presented. On June 9, 2012, NEMO-SN1 was successfully deployed and is working in real time.
The results of the analysis of the data collected with the NEMO Phase-2 tower, deployed at 3500m depth about 80km off-shore Capo Passero (Italy), are presented. Čerenkov photons detected with the ...photomultipliers tubes were used to reconstruct the tracks of atmospheric muons. Their zenith-angle distribution was measured and the results compared with Monte Carlo simulations. An evaluation of the systematic effects due to uncertainties on environmental and detector parameters is also included. The associated depth intensity relation was evaluated and compared with previous measurements and theoretical predictions. With the present analysis, the muon depth intensity relation has been measured up to 13km of water equivalent.
In the deep sea, the sense of time is dependent on geophysical fluctuations, such as internal tides and atmospheric-related inertial currents, rather than day-night rhythms. Deep-sea neutrino ...telescopes instrumented with light detecting Photo-Multiplier Tubes (PMT) can be used to describe the synchronization of bioluminescent activity of abyssopelagic organisms with hydrodynamic cycles. PMT readings at 8 different depths (from 3069 to 3349 m) of the NEMO Phase 2 prototype, deployed offshore Capo Passero (Sicily) at the KM3NeT-Italia site, were used to characterize rhythmic bioluminescence patterns in June 2013, in response to water mass movements. We found a significant (p < 0.05) 20.5 h periodicity in the bioluminescence signal, corresponding to inertial fluctuations. Waveform and Fourier analyses of PMT data and tower orientation were carried out to identify phases (i.e. the timing of peaks) by subdividing time series on the length of detected inertial periodicity. A phase overlap between rhythms and cycles suggests a mechanical stimulation of bioluminescence, as organisms carried by currents collide with the telescope infrastructure, resulting in the emission of light. A bathymetric shift in PMT phases indicated that organisms travelled in discontinuous deep-sea undular vortices consisting of chains of inertially pulsating mesoscale cyclones/anticyclones, which to date remain poorly known.
Recent achievements of the NEMO project Migneco, E.; Aiello, S.; Aloisio, A. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2008, Letnik:
588, Številka:
1-2
Journal Article
Recenzirano
The status of the activities towards the realization of a km3 Cherenkov neutrino detector carried out by the NEMO Collaboration is described. The realization of a Phase-1 project, which is under way, ...will validate the proposed technologies for the realization of the km3 detector on a Test Site at 2000m depth. The realization of a new infrastructure on the candidate site (Phase-2 project) will provide the possibility to test detector components at 3500m depth.
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