5,343 research outputs found
Factors affecting the diet of Peregrine Falcon in Italy
The diet of top predators can provide useful information on phenology and abundance of their prey. The cosmopolitan and specialist Peregrine Falcon (Falco peregrinus) is an ideal model to assess whether food changes have occurred in the long-term. In this contribution, we reviewed all available literature on Peregrine Falcon diet in Italy which contained 11 detailed datasets useful for our review, and also included analysis of pellets, collected at three breeding sites of Sicily during 2014 and 2015. These data allowed us to shed light on the Peregrine Falcon’s diet over the last forty years (1978-2015). We calculated the numerical and biomass percentage of the resident and not-resident prey proportions, as well as the trophic diversity of diet in each site using the Simpson diversity index. To describe the Peregrine Falcon food niche and investigate whether year, habitat and latitude effects existed in its diet, we used a 2nd-degree factorial ANOVA. Over 1,550 preys, 110 bird species accounted for 98.58% of frequency and 99.79% of biomass. Modelling showed a year effect, with the quota and biomass of resident prey species increasing across the forty years of the study period, in a way complementary to the decrease of the quota and biomass of not-resident prey species. Conversely, habitat and latitude predicted significantly trophic diversity that was larger in rural than urban habitats, and at northern than southern latitudes. The strong numerical and biomass decrease of not-resident preys in the trophic niche of Peregrine Falcon in Italy could be related to the negative population trends of both migratory and summer-breeder farmland species. Actually the bulk of prey of the Peregrine Falcon in Italy is formed by a restricted group of resident Corvidae and Columbidae, which have remarkably increased in the last years. This could trigger more dependence on resident prey in the long term, making the Peregrine Falcons more vulnerable to control programs or eradication of specific prey populations or exposing them locally to high risk of infections (chlamydiosis, avian trichomiasis) transferred by feral species
ATLAS RPC Quality Assurance results at INFN Lecce
The main results of the quality assurance tests performed on the Resistive
Plate Chamber used by the ATLAS experiment at LHC as muon trigger chambers are
reported and discussed.
Since July 2004, about 270 RPC units has been certified at INFN Lecce site
and delivered to CERN, for being integrated in the final muon station of the
ATLAS barrel region.
We show the key RPC characteristics which qualify the performance of this
detector technology as muon trigger chamber in the harsh LHC enviroments.
These are dark current, chamber efficiency, noise rate, gas volume
tomography, and gas leakage.Comment: Comments: 6 pages, 1 table, 9 figures Proceedings of XXV Physics in
Collision-Prague, Czech Republic, 6-9 July 200
ATLAS RPC Cosmic Ray Teststand at INFN Lecce
We describe the design and functionality of the cosmic ray teststand built at
INFN Lecce for ATLAS RPC quality control assurance.Comment: XXIV Physics in Collisions Conference (PIC04), Boston, USA, June
2004, 3 pages, LaTex, 2 eps figures. MONP0
Design, status and perspective of the Mu2e crystal calorimeter
The Mu2e experiment at Fermilab will search for the charged lepton flavor
violating process of neutrino-less coherent conversion in the field
of an aluminum nucleus. Mu2e will reach a single event sensitivity of about
that corresponds to four orders of magnitude improvements
with respect to the current best limit. The detector system consists of a straw
tube tracker and a crystal calorimeter made of undoped CsI coupled with Silicon
Photomultipliers. The calorimeter was designed to be operable in a harsh
environment where about 10 krad/year will be delivered in the hottest region
and work in presence of 1 T magnetic field. The calorimeter role is to perform
/e separation to suppress cosmic muons mimiking the signal, while
providing a high level trigger and a seeding the track search in the tracker.
In this paper we present the calorimeter design and the latest RD results.Comment: 4 pages, conference proceeding for a presentation held at TIPP'2017.
To be published on Springer Proceedings in Physic
Quality Assurance on a custom SiPMs array for the Mu2e experiment
The Mu2e experiment at Fermilab will search for the coherent
conversion on aluminum atoms. The detector system consists of a straw tube
tracker and a crystal calorimeter. A pre-production of 150 Silicon
Photomultiplier arrays for the Mu2e calorimeter has been procured. A detailed
quality assur- ance has been carried out on each SiPM for the determination of
its own operation voltage, gain, dark current and PDE. The measurement of the
mean-time-to-failure for a small random sample of the pro-production group has
been also completed as well as the determination of the dark current increase
as a function of the ioninizing and non-ioninizing dose.Comment: 4 pages, 10 figures, conference proceeding for NSS-MIC 201
The Mu2e undoped CsI crystal calorimeter
The Mu2e experiment at Fermilab will search for Charged Lepton Flavor
Violating conversion of a muon to an electron in an atomic field. The Mu2e
detector is composed of a tracker, an electromagnetic calorimeter and an
external system, surrounding the solenoid, to veto cosmic rays. The calorimeter
plays an important role to provide: a) excellent particle identification
capabilities; b) a fast trigger filter; c) an easier tracker track
reconstruction. Two disks, located downstream of the tracker, contain 674 pure
CsI crystals each. Each crystal is read out by two arrays of UV-extended SiPMs.
The choice of the crystals and SiPMs has been finalized after a thorough test
campaign. A first small scale prototype consisting of 51 crystals and 102 SiPM
arrays has been exposed to an electron beam at the BTF (Beam Test Facility) in
Frascati. Although the readout electronics were not the final, results show
that the current design is able to meet the timing and energy resolution
required by the Mu2e experiment.Comment: 6 pages, 8 figures, proceedings of the "Calorimetry for the high
energy frontier (CHEF17)" conference, 2-6 October 2017, Lyon, Franc
Single-hit resolution measurement with MEG II drift chamber prototypes
Drift chambers operated with helium-based gas mixtures represent a common
solution for tracking charged particles keeping the material budget in the
sensitive volume to a minimum. The drawback of this solution is the worsening
of the spatial resolution due to primary ionisation fluctuations, which is a
limiting factor for high granularity drift chambers like the MEG II tracker. We
report on the measurements performed on three different prototypes of the MEG
II drift chamber aimed at determining the achievable single-hit resolution. The
prototypes were operated with helium/isobutane gas mixtures and exposed to
cosmic rays, electron beams and radioactive sources. Direct measurements of the
single hit resolution performed with an external tracker returned a value of
110 m, consistent with the values obtained with indirect measurements
performed with the other prototypes.Comment: 18 pages, 18 figure
Ageing test of the ATLAS RPCs at X5-GIF
An ageing test of three ATLAS production RPC stations is in course at X5-GIF,
the CERN irradiation facility. The chamber efficiencies are monitored using
cosmic rays triggered by a scintillator hodoscope. Higher statistics
measurements are made when the X5 muon beam is available. We report here the
measurements of the efficiency versus operating voltage at different source
intensities, up to a maximum counting rate of about 700Hz/cm^2. We describe the
performance of the chambers during the test up to an overall ageing of 4 ATLAS
equivalent years corresponding to an integrated charge of 0.12C/cm^2, including
a safety factor of 5.Comment: 4 pages. Presented at the VII Workshop on Resistive Plate Chambers
and Related Detectors; Clermont-Ferrand October 20th-22nd, 200
MEG Upgrade Proposal
We propose the continuation of the MEG experiment to search for the charged
lepton flavour violating decay (cLFV) \mu \to e \gamma, based on an upgrade of
the experiment, which aims for a sensitivity enhancement of one order of
magnitude compared to the final MEG result, down to the
level. The key features of this new MEG upgrade are an increased rate
capability of all detectors to enable running at the intensity frontier and
improved energy, angular and timing resolutions, for both the positron and
photon arms of the detector. On the positron-side a new low-mass, single
volume, high granularity tracker is envisaged, in combination with a new highly
segmented, fast timing counter array, to track positron from a thinner stopping
target. The photon-arm, with the largest liquid xenon (LXe) detector in the
world, totalling 900 l, will also be improved by increasing the granularity at
the incident face, by replacing the current photomultiplier tubes (PMTs) with a
larger number of smaller photosensors and optimizing the photosensor layout
also on the lateral faces. A new DAQ scheme involving the implementation of a
new combined readout board capable of integrating the diverse functions of
digitization, trigger capability and splitter functionality into one condensed
unit, is also under development. We describe here the status of the MEG
experiment, the scientific merits of the upgrade and the experimental methods
we plan to use.Comment: A. M. Baldini and T. Mori Spokespersons. Research proposal submitted
to the Paul Scherrer Institute Research Committee for Particle Physics at the
Ring Cyclotron. 131 Page
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