2,171 research outputs found
A New Scintillator Tile/Fiber Preshower Detector for the CDF Central Calorimeter
A detector designed to measure early particle showers has been installed in
front of the central CDF calorimeter at the Tevatron. This new preshower
detector is based on scintillator tiles coupled to wavelength-shifting fibers
read out by multi-anode photomultipliers and has a total of 3,072 readout
channels. The replacement of the old gas detector was required due to an
expected increase in instantaneous luminosity of the Tevatron collider in the
next few years. Calorimeter coverage, jet energy resolution, and electron and
photon identification are among the expected improvements. The final detector
design, together with the R&D studies that led to the choice of scintillator
and fiber, mechanical assembly, and quality control are presented. The detector
was installed in the fall 2004 Tevatron shutdown and started collecting
colliding beam data by the end of the same year. First measurements indicate a
light yield of 12 photoelectrons/MIP, a more than two-fold increase over the
design goals.Comment: 5 pages, 10 figures (changes are minor; this is the final version
published in IEEE-Trans.Nucl.Sci.
Strong subadditivity for log-determinant of covariance matrices and its applications
We prove that the log-determinant of the covariance matrix obeys the strong subadditivity inequality for arbitrary tripartite states of multimode continuous variable quantum systems. This establishes general limitations on the distribution of information encoded in the second moments of canonically conjugate operators. The inequality is shown to be stronger than the conventional strong subadditivity inequality for von Neumann entropy in a class of pure tripartite Gaussian states. We finally show that such an inequality implies a strict monogamy-type constraint for joint Einstein-Podolsky-Rosen steerability of single modes by Gaussian measurements performed on multiple groups of modes
Forward Physics at the LHC (Elba 2010)
The papers review the main theoretical and experimental aspects of the
Forward Physics at the Large Hadron Collider
Rancang Bangun Sistem Pengenalan Wajah Daftar Pencarian Orang (Dpo) Berbasis Jaringan Saraf Tiruan
This study aims to design a system that is able to recognize the face of a people search list (DPO). The application is built using opencv and dlib ddan system testing is done with a dataset consisting of 6 target people. The target was identified when it was exactly perpendicular to the camera but the detection failed when the target\u27s face was not exactly perpendicular. This study also models the transmission of target data detected using long range radio (LORA) at a frequency of 91
Comparison of Leishmania killicki (syn. L-tropica) and Leishmania tropica population structure in Maghreb by microsatellite typing
Leishmania (L.) killicki (syn. L. tropica), which causes cutaneous leishmaniasis in Maghreb, was recently described in this region and identified as a subpopulation of L. tropica. The present genetic analysis was conducted to explore the spatio-temporal distribution of L. killicki (syn. L. tropica) and its transmission dynamics. To better understand the evolution of this parasite, its population structure was then compared with that of L. tropica populations from Morocco. In total 198 samples including 85 L. killicki (syn. L. tropica) (from Tunisia, Algeria and Libya) and 113 L. tropica specimens (all from Morocco) were tested. Theses samples were composed of 168 Leishmania strains isolated from human skin lesions, 27 DNA samples from human skin lesion biopsies, two DNA samples from Ctenodactylus gundi bone marrow and one DNA sample from a Phlebotomus sergenti female. The sample was analyzed by using MultiLocus Enzyme Electrophoresis (MLEE) and MultiLocus Microsatellite Typing (MLMT) approaches. Analysis of the MLMT data support the hypothesis that L. killicki (syn. L. tropica) belongs to the L. tropica complex, despite its strong genetic differentiation, and that it emerged from this taxon by a founder effect. Moreover, it revealed a strong structuring in L. killicki (syn. L. tropica) between Tunisia and Algeria and within the different Tunisian regions, suggesting low dispersion of L. killicki (syn. L. tropica) in space and time. Comparison of the L. tropica (exclusively from Morocco) and L. killicki (syn. L. tropica) population structures revealed distinct genetic organizations, reflecting different epidemiological cycles
The CDF Calorimetry Upgrade for Run IIb
The physics program at the Fermilab Tevatron Collider will continue to
explore the high energy frontier of particle physics until the commissioning of
the LHC at CERN. The luminosity increase provided by the Main Injector will
require upgrades beyond those implemented for the first stage (Run IIa) of the
Tevatron's Run II physics program. The upgrade of the CDF calorimetry includes:
1) the replacement of the slow gas detectors on the front face of the Central
Calorimeter with a faster scintillator version which has a better segmentation,
and 2) the addition of timing information to both the Central and EndPlug
Electromagnetic Calorimeters to filter out cosmic ray and beam related
backgrounds.Comment: Presented at `Frontier Detectors for Frontier Physics; 9th Pisa
Meeting on Advanced Detectors', Biodola, Italy, 25-31 May 2003. 2 page
LHC Optics Measurement with Proton Tracks Detected by the Roman Pots of the TOTEM Experiment
Precise knowledge of the beam optics at the LHC is crucial to fulfil the
physics goals of the TOTEM experiment, where the kinematics of the scattered
protons is reconstructed with the near-beam telescopes -- so-called Roman Pots
(RP). Before being detected, the protons' trajectories are influenced by the
magnetic fields of the accelerator lattice. Thus precise understanding of the
proton transport is of key importance for the experiment. A novel method of
optics evaluation is proposed which exploits kinematical distributions of
elastically scattered protons observed in the RPs. Theoretical predictions, as
well as Monte Carlo studies, show that the residual uncertainty of this optics
estimation method is smaller than 0.25 percent.Comment: 20 pages, 11 figures, 5 figures, to be submitted to New J. Phy
Double diffractive cross-section measurement in the forward region at LHC
The first double diffractive cross-section measurement in the very forward
region has been carried out by the TOTEM experiment at the LHC with
center-of-mass energy of sqrt(s)=7 TeV. By utilizing the very forward TOTEM
tracking detectors T1 and T2, which extend up to |eta|=6.5, a clean sample of
double diffractive pp events was extracted. From these events, we measured the
cross-section sigma_DD =(116 +- 25) mub for events where both diffractive
systems have 4.7 <|eta|_min < 6.5 .Comment: 5 pages, 1 figure, submitted for publicatio
Performance of the TOTEM Detectors at the LHC
The TOTEM Experiment is designed to measure the total proton-proton
cross-section with the luminosity-independent method and to study elastic and
diffractive pp scattering at the LHC. To achieve optimum forward coverage for
charged particles emitted by the pp collisions in the interaction point IP5,
two tracking telescopes, T1 and T2, are installed on each side of the IP in the
pseudorapidity region 3.1 < = |eta | < = 6.5, and special movable beam-pipe
insertions - called Roman Pots (RP) - are placed at distances of +- 147 m and
+- 220 m from IP5. This article describes in detail the working of the TOTEM
detector to produce physics results in the first three years of operation and
data taking at the LHC.Comment: 40 pages, 31 figures, submitted to Int. J. Mod. Phys.
Diamond Detectors for the TOTEM Timing Upgrade
This paper describes the design and the performance of the timing detector
developed by the TOTEM Collaboration for the Roman Pots (RPs) to measure the
Time-Of-Flight (TOF) of the protons produced in central diffractive
interactions at the LHC. The measurement of the TOF of the protons allows the
determination of the longitudinal position of the proton interaction vertex and
its association with one of the vertices reconstructed by the CMS detectors.
The TOF detector is based on single crystal Chemical Vapor Deposition (scCVD)
diamond plates and is designed to measure the protons TOF with about 50 ps time
precision. This upgrade to the TOTEM apparatus will be used in the LHC run 2
and will tag the central diffractive events up to an interaction pileup of
about 1. A dedicated fast and low noise electronics for the signal
amplification has been developed. The digitization of the diamond signal is
performed by sampling the waveform. After introducing the physics studies that
will most profit from the addition of these new detectors, we discuss in detail
the optimization and the performance of the first TOF detector installed in the
LHC in November 2015.Comment: 26 pages, 18 figures, 2 tables, submitted for publication to JINS
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