2,708 research outputs found
Usage of tracking in the CMS Level-1 trigger for the High Luminosity LHC Upgrade
At the High Luminosity LHC (HL-LHC), the CMS experiment will face a harsh
environment with a high instantaneous luminosity up to 7x10/cm/s
corresponding to an average of 140-200 multiple proton-proton collisions per
bunch crossing. The main goal of the CMS Level 1 (L1) trigger upgrade for the
HL-LHC is to maintain trigger thresholds that are as low as possible and
comparable to those currently in use at the LHC, and to possibly include new
triggers that were not feasible at the LHC. This will be achieved by upgrading
the detector readout electronics, to allow a much larger L1 trigger rate, and
by including, for the first time, tracking information in the L1 trigger.
Examples of how this tracking information can be used to reduce the L1 trigger
rates are presented.Comment: 2 pages, Contribution to the proceedings of 39th International
Conference on High Energy Physics (ICHEP) in Seoul, Korea, July 4-11 201
Top quark pair production and top quark properties at CDF
We present the most recent measurements of top quark pairs production and top
quark properties in proton-antiproton collisions with center-of-mass energy of
1.96 TeV using CDF II detector at the Tevatron. The combination of top pair
production cross section measurements and the direct measurement of top quark
width are reported. The test of Standard Model predictions for top quark
decaying into -quarks, performed by measuring the ratio between the top
quark branching fraction to -quark and the branching fraction to any type of
down quark is shown. The extraction of the CKM matrix element from
the ratio is discussed. We also present the latest measurements on the
forward-backward asymmetry () in top anti-top quark production. With
the full CDF Run II data set, the measurements are performed in top anti-top
decaying to final states that contain one or two charged leptons (electrons or
muons). In addition, we combine the results of the leptonic forward-backward
asymmetry in system between the two final states. All the results
show deviations from the next-to-leading order (NLO) standard model (SM)
calculation.Comment: 6 pages, 5 figures, Contribution to the proceedings of 37th
International Conference on High Energy Physics (ICHEP) in Valencia, Spain,
July 2-9 201
Top Physics at CDF
We present the recent results of top-quark physics using up to 6 fb of
collisions at a center of mass energy of = 1.96 TeV
analyzed by the CDF collaboration. Thanks to this large data sample, precision
top quark measurements are now a reality at the Tevatron. Further, several new
physics signals could appear in this large dataset. We will present the latest
measurements of top quark intrinsic properties as well as direct searches for
new physics in the top sector.Comment: Contribution to the proceedings of XIX International Workshop on
Deep-Inelastic Scattering and Related Subjects (DIS 2011), 4 page
Level-1 pixel based tracking trigger algorithm for LHC upgrade
The Pixel Detector is the innermost detector of the tracking system of the
Compact Muon Solenoid (CMS) experiment at CERN Large Hadron Collider (LHC). It
precisely determines the interaction point (primary vertex) of the events and
the possible secondary vertexes due to heavy flavours ( and quarks); it
is part of the overall tracking system that allows reconstructing the tracks of
the charged particles in the events and combined with the magnetic field to
measure their impulsion. The pixel detector allows measuring the tracks in the
region closest to the interaction point. The Level-1 (real-time) pixel based
tracking trigger is a novel trigger system that is currently being studied for
the LHC upgrade. An important goal is developing real-time track reconstruction
algorithms able to cope with very high rates and high flux of data in a very
harsh environment. The pixel detector has an especially crucial role in
precisely identifying the primary vertex of the rare physics events from the
large pile-up (PU) of events. The goal of adding the pixel information already
at the real-time level of the selection is to help reducing the total level-1
trigger rate while keeping an high selection capability. This is quite an
innovative and challenging objective for the experiments upgrade for the High
Luminosity LHC (HL-LHC). The special case here addressed is the CMS experiment.
This document describes exercises focusing on the development of a fast pixel
track reconstruction where the pixel track matches with a Level-1 electron
object using a ROOT-based simulation framework.Comment: Submitted to JINST; 12 pages, 10 figures, Contribution to the JINST
proceedings for the INFIERI2014 School in Paris, France, July 14-25, 201
Production of single top quark - results from the Tevatron and the LHC
We present the most recent measurements of single top quark production cross
section by the CDF and D0 experiments at the Fermilab Tevatron Collider and the
ATLAS and CMS experiments at the Large Hadron Collider (LHC). The data were
collected at the Tevatron corresponding to an integrated luminosity of up to
9.7 fb of proton-antiproton () collisions at a centre-of-mass
energy of 1.96 TeV and at the LHC corresponding to an integrated luminosity of
up to 4.9 fb of proton-proton () collisions at a centre-of-mass
energy of 7 TeV in 2011 and up to 20.3 fb at a centre-of-mass energy of
8 TeV in 2012. The measurements of single top quark production in -channel,
-channel and associated production of a top quark and a -boson (
production) are presented separately and lower limits on the CKM matrix element
from the single top quark cross section are set.Comment: 5 pages, 4 figures, for the ATLAS, CDF, CMS and D0 collaborations,
Presented at 26th Rencontres de Blois, Particle Physics and Cosmology, May
18-23, 201
Pixel data real time processing as a next step for HL-LHC upgrades and beyond
The experiments at LHC are implementing novel and challenging detector
upgrades for the High Luminosity LHC, among which the tracking systems. This
paper reports on performance studies, illustrated by an electron trigger, using
a simplified pixel tracker. To achieve a real-time trigger (e.g. processing
HL-LHC collision events at 40 MHz), simple algorithms are developed for
reconstructing pixel-based tracks and track isolation, utilizing look-up tables
based on pixel detector information. Significant gains in electron trigger
performance are seen when pixel detector information is included. In
particular, a rate reduction up to a factor of 20 is obtained with a signal
selection efficiency of more than 95\% over the whole coverage of this
detector. Furthermore, it reconstructs p-p collision points in the beam axis
(z) direction, with a high precision of 20 m resolution in the very
central region (), and, up to 380 m in the forward region
(2.7 3.0). This study as well as the results can easily be adapted
to the muon case and to the different tracking systems at LHC and other
machines beyond the HL-LHC. The feasibility of such a real-time processing of
the pixel information is mainly constrained by the Level-1 trigger latency of
the experiment. How this might be overcome by the Front-End ASIC design, new
processors and embedded Artificial Intelligence algorithms is briefly tackled
as well.Comment: To be submitted to JHE
Functional elements demarcated by histone modifications in breast cancer cells
AbstractHistone modifications are regarded as one of markers to identify regulatory elements which are DNA segments modulating gene transcription. Aberrant changes of histone modification levels are frequently observed in cancer. We have employed ChIP-Seq to identify regulatory elements in human breast cancer cell line, MCF-7 by comparing histone modification patterns of H3K4me1, H3K4me3, and H3K9/14ac to those in normal mammary epithelial cell line, MCF-10A. The genome-wide analysis shows that H3K4me3 and H3K9/14ac are highly enriched at promoter regions and H3K4me1 has a relatively broad distribution over proximity of TSSs as well as other genomic regions. We identified that many differentially expressed genes in MCF-7 have divergent histone modification patterns. To understand the functional roles of distinctively histone-modified regions, we selected 35 genomic regions marked by at least one histone modification and located from 3 to 10kb upstream of TSS in both MCF-7 and MCF-10A and assessed their transcriptional activities. About 66% and 60% of selected regions in MCF-7 and MCF-10A, respectively, enhanced the transcriptional activity. Interestingly, most regions marked by H3K4me1 exhibited an enhancer activity. Regions with two or more kinds of histone modifications did show varying activities. In conclusion, our data reflects that comprehensive analysis of histone modification profiles under cell type-specific chromatin environment should provide a better chance for defining functional regulatory elements in the genome
Lung cancer with superior vena cava syndrome diagnosed by intravascular biopsy using EBUS-TBNA
AbstractSince superior vena cava syndrome (SVCS) is a critical condition, immediate diagnostic approach and therapy are imperative to avoid potentially life-threatening complications. Here, we report a case of lung cancer with SVCS, which was diagnosed through intravascular tumor biopsy using endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). EBUS-TBNA enabled us to obtain tissue sufficient for diagnosis, without significant complications. Prompt diagnosis was followed by appropriate anticancer treatment and improvement in the symptoms. For patients suspected of SVCS and requiring prompt pathologic diagnosis, we can consider EBUS-TBNA to diagnose intravascular or mediastinal tumors and provide an accurate diagnosis
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