A
bstract
We describe a proposal to add a set of very forward detectors to the CMS experiment for the high-luminosity era of the Large Hadron Collider to search for beyond the standard model ...long-lived particles, such as dark photons, heavy neutral leptons, axion-like particles, and dark Higgs bosons. The proposed subsystem is called
FACET
for
F
orward-
A
perture
C
MS
E
x
T
ension, and will be sensitive to any particles that can penetrate at least 50 m of magnetized iron and decay in an 18 m long, 1 m diameter vacuum pipe. The decay products will be measured in detectors using identical technology to the planned CMS Phase-2 upgrade.
Electroweak physics at the LHC Berryhill, J; Oh, A
Journal of physics. G, Nuclear and particle physics,
02/2017, Letnik:
44, Številka:
2
Journal Article
Recenzirano
The Large Hadron Collider (LHC) has completed in 2012 its first running phase and the experiments have collected data sets of proton-proton collisions at center-of-mass energies of 7 and 8 TeV with ...an integrated luminosity of about 5 and 20 fb − 1 , respectively. Analyses of these data sets have produced a rich set of results in the electroweak sector of the standard model. This article reviews the status of electroweak measurements of the ATLAS, CMS and LHCb experiments at the LHC.
Little is known about the diagnostic validity of the 15‐item Geriatric Depression Scale ‐ Short Form (GDS‐SF), especially when compared to the original 30‐item version (Geriatric Depression Scale ‐ ...Long Form; GDS‐LF). This study compared the GDS‐SF and GDS‐LF with a sample of depressed, demented, and thought‐disordered inpatients. The GDS‐SF and GDS‐LF were found to be highly correlated (r = .89) and to have similar high sensitivity rates. The specificity rates for both forms were similar, but lower than desirable. Overall, the GDS‐SF was found to be an adequate substitute for the GDS‐LF.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
4.
The CDF Silicon Vertex Trigger Ashmanskas, Bill; Barchiesi, A.; Bardi, A. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2004, Letnik:
518, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The Collider Detector at Fermilab (CDF) experiment's Silicon Vertex Trigger (SVT) is a system of 150 custom 9U VME boards that reconstructs axial tracks in the CDF silicon strip detector in a
15
μs
...pipeline. SVT's
35
μm
impact parameter resolution enables CDF's Level 2 trigger to distinguish primary and secondary particles, and hence to collect large samples of hadronic bottom and charm decays. We review some of SVT's key design features. Speed is achieved with custom VLSI pattern recognition, linearized track fitting, pipelining, and parallel processing. Testing and reliability are aided by built-in logic state analysis and test-data sourcing at each board's input and output, a common interboard data link, and a universal “Merger” board for data fan-in/fan-out. Speed and adaptability are enhanced by use of modern FPGAs.
As discipline-based astronomy education researchers become more interested in experimentally testing innovative teaching strategies to enhance learning in undergraduate introductory astronomy survey ...courses ("ASTRO 101"), scholars are placing increased attention toward better understanding factors impacting student gain scores on the widely used Test Of Astronomy STandards (TOAST). Usually used in a pre-test and post-test study design, college faculty might naturally assume that the pre-course differences observed between high- and low-scoring college students might be due in large part to their pre-existing motivation, interest, experience in science, and attitudes about astronomy. To explore this notion, 11 non-science majoring undergraduates taking ASTRO 101 at west coast community colleges were interviewed in the first few weeks of the course after taking the TOAST as a pre-test to better understand students' pre-existing affect toward learning astronomy with an eye toward predicting student success. The goal is to contribute to a better understanding of the incoming knowledge of students taking undergraduate introductory astronomy classes and provide guidance for how faculty can best meet those students' needs and assist them in greater achievement. Perhaps surprisingly, there was only weak correlation between students' motivation toward learning astronomy and their pre-test scores. Instead, the most fruitful predictor of TOAST pre-test scores was the quantity of pre-existing, informal, self-directed astronomy learning experiences, sometimes occurring many years before course enrollment. This data suggests that professors should be wary of correlating low incoming pre-course scores with student apathy toward their subject.
B, D and K decays Buchalla, G.; Komatsubara, T. K.; Muheim, F. ...
European physical journal. C, Particles and fields (Print),
09/2008, Letnik:
57, Številka:
1-2
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
The present report documents the results of Working Group 2:
B
,
D
and
K
decays, of the workshop on Flavor in the Era of the LHC, held at CERN from November 2005 through March 2007.
With the advent ...of the LHC, we will be able to probe New Physics (NP) up to energy scales almost one order of magnitude larger than it has been possible with present accelerator facilities. While direct detection of new particles will be the main avenue to establish the presence of NP at the LHC, indirect searches will provide precious complementary information, since most probably it will not be possible to measure the full spectrum of new particles and their couplings through direct production. In particular, precision measurements and computations in the realm of flavor physics are expected to play a key role in constraining the unknown parameters of the Lagrangian of any NP model emerging from direct searches at the LHC.
The aim of Working Group 2 was twofold: on the one hand, to provide a coherent up-to-date picture of the status of flavor physics before the start of the LHC; on the other hand, to initiate activities on the path towards integrating information on NP from high-
p
T
and flavor data.
This report is organized as follows: in Sect. 1, we give an overview of NP models, focusing on a few examples that have been discussed in some detail during the workshop, with a short description of the available computational tools for flavor observables in NP models. Section 2 contains a concise discussion of the main theoretical problem in flavor physics: the evaluation of the relevant hadronic matrix elements for weak decays. Section 3 contains a detailed discussion of NP effects in a set of flavor observables that we identified as “benchmark channels” for NP searches. The experimental prospects for flavor physics at future facilities are discussed in Sect. 4. Finally, Sect. 5 contains some assessments on the work done at the workshop and the prospects for future developments.
In support of teaching astronomy as a human enterprise, modern astronomy teaching often emphasizes visuals—whether heavenly telescope images of the cosmos or graphs depicting the relationships ...between physical process variables. Well-known suggestions of how to have students individually interact with images and graphics pepper earlier AstroNotes columns: teaching strategies that challenge students to provide missing labels to diagrams or to create their own graphical representations using small, individual whiteboards. We suggest here a method of intellectually engaging large groups of students with a large image or graphic that is projected in the front of the room.
Silicon vertex tracker: a fast precise tracking trigger for CDF Ashmanskas, W; Bardi, A; Bari, M ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
06/2000, Letnik:
447, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The Silicon Vertex Tracker (SVT), currently being built for the CDF II experiment, is a hardware device that reconstructs 2-D tracks online using measurements from the Silicon Vertex Detector (SVXII) ...and the Central Outer Tracker (COT). The precise measurement of the impact parameter of the SVT tracks will allow, for the first time in a hadron collider environment, to trigger on events containing B hadrons that are very important for many studies, such as CP violation in the b sector and searching for new heavy particles decaying to b
b
̄
. In this report we describe the overall architecture, algorithms and the hardware implementation of the SVT.
The CDF online Silicon Vertex Tracker Ashmanskas, W.; Bardi, A.; Bari, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
06/2002, Letnik:
485, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The CDF Online Silicon Vertex Tracker (SVT) reconstructs 2D tracks by linking hit positions measured by the Silicon Vertex Detector to the Central Outer Chamber tracks found by the eXtremely Fast ...Tracker (XFT). The system has been completely built and assembled and it is now being commissioned using the first CDF run II data. The precision measurement of the track impact parameter will allow triggering on B hadron decay vertices and thus investigating important areas in the B sector, like CP violation and B
s mixing. In this paper we briefly review the architecture and the tracking algorithms implemented in the SVT and we report on the performance of the system achieved in the early phase of CDF run II.
SVT: an online Silicon Vertex Tracker for the CDF upgrade Bardi, A.; Belforte, S.; Berryhill, J. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/1998, Letnik:
409, Številka:
1-3
Journal Article
Recenzirano
Odprti dostop
The SVT is an online tracker for the CDF upgrade which will reconstruct 2D tracks using information from the Silicon VerteX detector (SVXII) and Central Outer Tracker (COT). The precision measurement ...of the track impact parameter will then be used to select and record large samples of B hadrons. We discuss the overall architecture, algorithms, and hardware implementation of the system.
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