16,676 research outputs found
Waldschmidt constants for Stanley-Reisner ideals of a class of graphs
In the present note we study Waldschmidt constants of Stanley-Reisner ideals
of a hypergraph and a graph with vertices forming a bipyramid over a planar
n-gon. The case of the hypergraph has been studied by Bocci and Franci. We
reprove their main result. The case of the graph is new. Interestingly, both
cases provide series of ideals with Waldschmidt constants descending to 1. It
would be interesting to known if there are bounded ascending sequences of
Waldschmidt constants.Comment: 7 pages, 2 figure
TRT Alignment For SR1 Cosmics and Beyond
We present an algorithm for the alignment of the ATLAS Inner Detector, developed for the analysis of cosmics data taken with the ID barrel in SR1 in the summer of 2006. Our results include a comparison of the relative SCT-TRT alignment with survey measurements, a study of the alignment of SCT and TRT module positions and TRT module deformations, and a comparison of the `local' and `global' methods for alignment
Intervista agli esperti di comunicazione intergenerazionale
Nell'intervista si illustrano le origini dell’interesse per il tema della comunicazione intergenerazionale e i successivi sviluppi delle ricerche/sperimentazioni di turismo intergenerazionale in Italia, specificandone le motivazioni, i contesti, le reti territoriali, i target e i risultati più salienti. Si evidenzia la stretta relazione tra ricerca, formazione e progettualità presentando l'innovativo profilo professionale del Manager in ambiente e turismo intergenerazionale
Probabilistic Particle Flow Algorithm for High Occupancy Environment
Algorithms based on the particle flow approach are becoming increasingly
utilized in collider experiments due to their superior jet energy and missing
energy resolution compared to the traditional calorimeter-based measurements.
Such methods have been shown to work well in environments with low occupancy of
particles per unit of calorimeter granularity. However, at higher instantaneous
luminosity or in detectors with coarse calorimeter segmentation, the overlaps
of calorimeter energy deposits from charged and neutral particles significantly
complicate particle energy reconstruction, reducing the overall energy
resolution of the method. We present a technique designed to resolve
overlapping energy depositions of spatially close particles using a
statistically consistent probabilistic procedure. The technique is nearly free
of ad-hoc corrections, improves energy resolution, and provides new important
handles that can improve the sensitivity of physics analyses: the uncertainty
of the jet energy on an event-by-event basis and the estimate of the
probability of a given particle hypothesis for a given detector response. When
applied to the reconstruction of hadronic jets produced in the decays of tau
leptons using the CDF-II detector at Fermilab, the method has demonstrated
reliable and robust performance.Comment: Accepted by Nuclear Instruments and Methods
Cultivating diversity and food quality. Proceedings of Diversifood EU Forum, Brussels, 11 April 2018
To tackle this issue, Diversifood team organised a forum with policy makers and stakeholders on the 11th of April 2018, in Brussels.
Diversifood’s aim is to share results and key lessons including new approaches for the management of cultivated biodiversity, for plant breeding for sustainable farming systems, and new relationships among actors of food systems.
In the afternoon, there was time for discussion, knowledge sharing, collecting feedback and extending current policies to include cultivating diversity and food quality (for FP9, CAP 2020, The outputs of this workshop will feed Diversifood’s final recommendations.
The forum was kindly hosted by the European Committee of the Regions (Rue Belliard/Belliardstraat 101, 1040 Brussels)
Search for supersymmetry in pp collisions at 7 TeV in events with jets and missing transverse energy
Acknowledge support from:
FMSR (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ,
and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC
(China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus);
Academy of Sciences and NICPB (Estonia); Academy of Finland,
ME, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG,
and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary);
DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF
and WCU (Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and
UASLP-FAI (Mexico); PAEC (Pakistan); SCSR (Poland); FCT (Portugal);
JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); MST
and MAE (Russia); MSTD (Serbia); MICINN and CPAN (Spain); Swiss
Funding Agencies (Switzerland); NSC (Taipei); TUBITAK and TAEK
(Turkey); STFC (United Kingdom); DOE and NSF (USA).A search for supersymmetry with R-parity conservation in proton–proton collisions at a centre-of-mass
energy of 7 TeV is presented. The data correspond to an integrated luminosity of 35 pb−1 collected by
the CMS experiment at the LHC. The search is performed in events with jets and significant missing
transverse energy, characteristic of the decays of heavy, pair-produced squarks and gluinos. The primary
background, from standard model multijet production, is reduced by several orders of magnitude to a
negligible level by the application of a set of robust kinematic requirements. With this selection, the
data are consistent with the standard model backgrounds, namely t¯t, W + jet and Z + jet production,
which are estimated from data control samples. Limits are set on the parameters of the constrained
minimal supersymmetric extension of the standard model. These limits extend those set previously by
experiments at the Tevatron and LEP colliders.23 páginas, 5 figuras, 2 tablas.-- Open access:
This article is distributed under the terms of the Creative Commons Attribution
License 3.0.-- CMS Collaboration: et al.Peer reviewe
Hydrogen vs. Battery in the long-term operation. A comparative between energy management strategies for hybrid renewable microgrids
The growth of the world’s energy demand over recent decades in relation to energy intensity and demography is clear. At the same time, the use of renewable energy sources is pursued to address decarbonization targets, but the stochasticity of renewable energy systems produces an increasing need for management systems to supply such energy volume while guaranteeing, at the same time, the security and reliability of the microgrids. Locally distributed energy storage systems (ESS) may provide the capacity to temporarily decouple production and demand. In this sense, the most implemented ESS in local energy districts are small–medium-scale electrochemical batteries. However, hydrogen systems are viable for storing larger energy quantities thanks to its intrinsic high mass-energy density. To match generation, demand and storage, energy management systems (EMSs) become crucial. This paper compares two strategies for an energy management system based on hydrogen-priority vs. battery-priority for the operation of a hybrid renewable microgrid. The overall performance of the two mentioned strategies is compared in the long-term operation via a set of evaluation parameters defined by the unmet load, storage efficiency, operating hours and cumulative energy. The results show that the hydrogen-priority strategy allows the microgrid to be led towards island operation because it saves a higher amount of energy, while the battery-priority strategy reduces the energy efficiency in the storage round trip. The main contribution of this work lies in the demonstration that conventional EMS for microgrids’ operation based on battery-priority strategy should turn into hydrogen-priority to keep the reliability and independence of the microgrid in the long-term operation
Performance of upstream interaction region detectors for the FIRST experiment at GSI
The FIRST (Fragmentation of Ions Relevant for Space and Therapy) experiment at GSI has been designed to study carbon fragmentation, measuring 12C double differential cross sections (∂2σ/ ∂θ∂E) for different beam energies between 100 and 1000 MeV/u. The experimental setup integrates newly designed detectors in the, so called, Interaction Region around the graphite target. The Interaction Region upstream detectors are a 250 μm thick scintillator and a drift chamber optimized for a precise measurement of the ions interaction time and position on the target. In this article we review the design of the upstream detectors along with the preliminary results of the data taking performed on August 2011 with 400 MeV/u fully stripped carbon ion beam at GSI. Detectors performances will be reviewed and compared to those obtained during preliminary tests, performed with 500 MeV electrons (at the BTF facility in the INFN Frascati Laboratories) and 80 MeV/u protons and carbon ions (at the INFN LNS Laboratories in Catania)
Use of bremsstrahlung radiation to identify hidden weak beta- sources: feasibility and possible use in radio-guided surgery
The recent interest in beta- radionuclides for radio-guided surgery derives
from the feature of the beta radiation to release energy in few millimeters of
tissue. Such feature can be used to locate residual tumors with a probe located
in its immediate vicinity, determining the resection margins with an accuracy
of millimeters. The drawback of this technique is that it does not allow to
identify tumors hidden in more than few mm of tissue. Conversely, the
bremsstrahlung X-rays emitted by the interaction of the beta- radiation with
the nuclei of the tissue are relatively penetrating. To complement the beta-
probes, we have therefore developed a detector based on cadmium telluride, an
X-ray detector with a high quantum efficiency working at room temperature. We
measured the secondary emission of bremsstrahlung photons in a target of
Polymethylmethacrylate (PMMA) with a density similar to living tissue. The
results show that this device allows to detect a 1 ml residual or lymph-node
with an activity of 1 kBq hidden under a layer of 10 mm of PMMA with a 3:1
signal to noise, i.e. with a five sigma discrimination in less than 5 s
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