4,076 research outputs found
The Future of RICH Detectors through the Light of the LHCb RICH
The limitations in performance of the present RICH system in the LHCb
experiment are given by the natural chromatic dispersion of the gaseous
Cherenkov radiator, the aberrations of the optical system and the pixel size of
the photon detectors. Moreover, the overall PID performance can be affected by
high detector occupancy as the pattern recognition becomes more difficult with
high particle multiplicities. This paper shows a way to improve performance by
systematically addressing each of the previously mentioned limitations. These
ideas are applied in the present and future upgrade phases of the LHCb
experiment. Although applied to specific circumstances, they are used as a
paradigm on what is achievable in the development and realisation of high
precision RICH detectors
Observing Ultra High Energy Cosmic Particles from Space: SEUSO, the Super Extreme Universe Space Observatory Mission
The experimental search for ultra high energy cosmic messengers, from eV to beyond eV, at the very end of the known energy
spectrum, constitutes an extraordinary opportunity to explore a largely unknown
aspect of our universe. Key scientific goals are the identification of the
sources of ultra high energy particles, the measurement of their spectra and
the study of galactic and local intergalactic magnetic fields. Ultra high
energy particles might, also, carry evidence of unknown physics or of exotic
particles relics of the early universe. To meet this challenge a significant
increase in the integrated exposure is required. This implies a new class of
experiments with larger acceptances and good understanding of the systematic
uncertainties. Space based observatories can reach the instantaneous aperture
and the integrated exposure necessary to systematically explore the ultra high
energy universe. In this paper, after briefly summarising the science case of
the mission, we describe the scientific goals and requirements of the SEUSO
concept. We then introduce the SEUSO observational approach and describe the
main instrument and mission features. We conclude discussing the expected
performance of the mission
Analysis and correction of the magnetic field effects in the Hybrid Photo-Detectors of the RICH2 Ring Imaging Cherenkov detector of LHCb
The Ring Imaging Cherenkov detectors of the LHCb experiment at the Large
Hadron Collider at CERN are equipped with Hybrid Photo-Detectors. These vacuum
photo-detectors are affected by the stray magnetic field of the LHCb magnet,
which degrades their imaging properties. This effect increases the error on the
Cherenkov angle measurement and would reduce the particle identification
capabilities of LHCb. A system has been developed for the RICH2 Ring Imaging
Cherenkov detector to perform a detailed characterisation of the magnetic
distortion effects. It is described, along with the methods implemented to
correct for these effects, restoring the optimal resolution.Comment: 16 pages, 11 figure
Update on vaccination of preterm infants: a systematic review about safety and efficacy/effectiveness. Proposal for a position statement by Italian Society of Pediatric Allergology and Immunology jointly with the Italian Society of Neonatology
Preterm infants (PIs) are at increased risk of vaccine-preventable diseases (VPDs). However, delayed vaccination start and low vaccine coverage are still reported. Areas covered: This systematic review includes 37 articles on preterm vaccination published in 2008-2018 in PubMed. Both live attenuated and inactivated vaccines are safe and well tolerated in PIs. Local reactions, apnea, and reactivity changes are the most frequently reported adverse events. Lower gestational age and birth weight, preimmunization apnea, longer use of continuous positive airway pressure (CPAP) are risk factors for apnea. The proportion of PIs who develop protective humoral and cellular immunity is generally similar to full terms although later gestational age is associated with increased antibody IgG concentrations (i.e. against certain pneumococcal serotypes, influenza, hepatitis B virus and poliovirus 1) and increased mononuclear cells proliferation (i.e. after inactivated poliovirus). Expert opinion: PIs can be safely and adequately protected by available vaccines with the same schedule used for full terms. Data at this regard have been retrieved by studies using a 3-dose primary series for pneumococcal and hexavalent vaccines. Further studies are needed regarding the 2 + 1 schedule. Apnea represents a nonspecific stress response in PIs, thus those hospitalized at 2 months should have cardio-respiratory monitoring after their first vaccination
Test of the photon detection system for the LHCb RICH Upgrade in a charged particle beam
The LHCb detector will be upgraded to make more efficient use of the
available luminosity at the LHC in Run III and extend its potential for
discovery. The Ring Imaging Cherenkov detectors are key components of the LHCb
detector for particle identification. In this paper we describe the setup and
the results of tests in a charged particle beam, carried out to assess
prototypes of the upgraded opto-electronic chain from the Multi-Anode PMT
photosensor to the readout and data acquisition system.Comment: 25 pages, 22 figure
ESAF: Full Simulation of Space-Based Extensive Air Showers Detectors
Future detection of Extensive Air Showers (EAS) produced by Ultra High Energy
Cosmic Particles (UHECP) by means of space based fluorescence telescopes will
open a new window on the universe and allow cosmic ray and neutrino astronomy
at a level that is virtually impossible for ground based detectors. In this
paper we summarize the results obtained in the context of the EUSO project by
means of a detailed Monte Carlo simulation of all the physical processes
involved in the fluorescence technique, from the Extensive Air Shower
development to the instrument response. Particular emphasis is given to
modeling the light propagation in the atmosphere and the effect of clouds. Main
results on energy threshold and resolution, direction resolution and Xmax
determination are reported. Results are based on EUSO telescope design, but are
also extended to larger and more sensitive detectors.Comment: 38 pages, 48 figures Corrected typos. Changed content. Added figure
Requirements and simulation study of the performance of EUSO as external payload on board the International Space Station
The "Extreme Universe Space Observatory - EUSO" has been conceived as the first Space mission devoted to the investigation of Ultra High Energy Cosmic Ray, using the Earth's atmosphere as a giant detector. The scientific objectives of the experiment are to observe the UHECR spectrum above the GZK energy, with an improvement of one order of magnitude in the statistics of collected events with respect to the existing experiments, in such a way to study the source distribution in a full sky survey, as well as to open the channel (set a confidence limit) on the neutrino astronomy in this energy range. Supposed to be accommodated as external payload on board the International Space Station, EUSO phase A study has been positively completed in July 2004. Nowadays, due to funding problems of the Space Agencies involved in the project, EUSO is currently on hold. Nevertheless, as result of an end-to-end simulation approach, we summarize here the expected scientific performance coming out from the phase A, as well as the expected improvements in the technical performance of the EUSO Instrument to be achieved during Phase B, in order to fulfil the scientific objectives posed as goal of the experiment
The EUSO simulation and analysis framework
ESAF is the simulation and analysis software framework developed for the EUSO experiment. ESAF's scope is the whole process of data simulations and data-analysis, from the primary particle interaction in atmosphere to the reconstruction of the event. Based on the ROOT package and designed using Object Oriented technology, ESAF is organized in two main programs: the full montecarlo simulation and the reconstruction framework. The former includes all the relevant physical contributions, shower development in atmosphere, light transport to the detector pupil and detector response, while the latter comprises basic data cleaning, track direction, shower profile and energy reconstruction algorithms. Here we describe the software architecture and its main features
Extreme Energy Cosmic Rays (EECR) Observation Capabilities of an "Airwatch from Space'' Mission
The longitudinal development and other characteristics of the EECR induced
atmospheric showers can be studied from space by detecting the fluorescence
light induced in the atmospheric nitrogen. According to the Airwatch concept a
single fast detector can be used for measuring both intensity and time
development of the streak of fluorescence light produced by the atmospheric
shower induced by an EECR. In the present communication the detection
capabilities for the EECR observation from space are discussed.Comment: 3 pages (LaTeX). To appear in the Proceedings of TAUP'9
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