1,180 research outputs found
Architecture of a Silicon Strip Beam Position Monitor
A collaboration between Fermilab and the Institute for High Energy Physics
(IHEP), Beijing, has developed a beam position monitor for the IHEP test beam
facility. This telescope is based on 5 stations of silicon strip detectors
having a pitch of 60 microns. The total active area of each layer of the
detector is about 12x10 cm2. Readout of the strips is provided through the use
of VA1` ASICs mounted on custom hybrid printed circuit boards and interfaced to
Adapter Cards via copper-over-kapton flexible circuits. The Adapter Cards
amplify and level-shift the signal for input to the Fermilab CAPTAN data
acquisition nodes for data readout and channel configuration. These nodes
deliver readout and temperature data from triggered events to an analysis
computer over gigabit Ethernet links.Comment: Submitted to TWEPP 201
Photon Cross Sections at Ecm = 2 TeV
Photon production rates have been studied by the D0 and CDF experiments in
Run II of the Fermilab Tevatron Collider. Measurements of the inclusive
isolated photon cross section and the di-photon cross section are presented,
based on integrated luminosities of 0.3 fb-1 and 0.2 fb-1, respectively. The
results are compared to perturbative QCD calculations in various
approximations.Comment: 4 pages 2 figures, presented at XLIrst Rencontres de Moriond on ``QCD
and High Energy Hadronic Interactions'', La Thuile, Italy, March 18-25, 2006,
on behalf of the CDF and D0 collaboration
Towards a precise measurement of the top quark Yukawa coupling at the ILC
A precise measurement of the top quark Yukawa coupling is of great
importance, since it may shed light on the mechanism of EWSB. We study the
prospects of such measurement during the first phase of the ILC at sqrt(s)=500
GeV, focusing in particular on recent theoretical developments as well as the
potential benefits of beam polarization. It is shown that both yield
improvements that could possibly lead to a measurement competitive with the
LHC.Comment: Invited talk at 2005 International Linear Collider Physics and
Detector Workshop and Second ILC Accelerator Workshop, Snowmass, CO
(Snowmass05) 3 pages, LaTeX, 3 eps figure
Searches for New Physics in Top Events at the Tevatron
Recent results of searches for new physics in top events at the Tevatron are
presented. In case of CDF three searches are discussed using 6.0 to 8.7 fb^{-1}
of data, with the latter being the final CDF data sample available for this
kind of analysis. CDF carried out a search for Top + jet resonance production,
dark matter production in association with single top and boosted tops. No
signs of new physics are observed and instead upper limits are derived. D{\O}
used 5.3 fb^{-1} of data and searched for a narrow resonance in ttbar
production and a time dependent ttbar cross section, which would reveal a
violation of Lorentz invariance. However, no signs for deviations from Standard
Model are seen and instead upper limits for non-Standard Model contributions
are calculated.Comment: 4 pages, 7 figures, To appear in Proceedings of Moriond QCD 201
Bs, Bc and b-baryons
We present the latest measurements on masses, lifetimes and branching
fractions for the B_s and B_c mesons as well as for b-baryons. For the B_s
meson we discuss as well the latest results on mixing. These results were
produced by the CDF and D0 experiments at Fermilab or by earlier LEP and PEPII
experiments.Comment: 13 pages, 17 figures, contribution to the Proceedings of the 25th
International Symposium on Physics in Collision (PIC 05), Prague, Czech
Republic, July 6-9, 2005 (In version 2 there were a couple of typos fixed and
a reference added in section 2
Transport from the Recycler Ring to the Antiproton Source Beamlines
In the post-Nova era, the protons are directly transported from the Booster
ring to the Recycler ring rather than the Main Injector. For Mu2e and g-2
project, the Debuncher ring will be modified into a Delivery ring to deliver
the protons to both Mu2e and g-2 experiemnts. Therefore, It requires the
transport of protons from the Recycler Ring to the Delivery ring. A new
transfer line from the Recycler ring to the P1 beamline will be constructed to
transport proton beam from the Recycler Ring to existing Antiproton Source
beamlines. This new beamline provides a way to deliver 8 GeV kinetic energy
protons from the Booster to the Delivery ring, via the Recycler, using existing
beam transport lines, and without the need for new civil construction. This
paper presents the Conceptual Design of this new beamline.Comment: 3 pp. 3rd International Particle Accelerator Conference (IPAC 2012)
20-25 May 2012. New Orleans, Louisian
Recycler barrier RF buckets
The Recycler Ring at Fermilab uses a barrier rf system for all of its rf
manipulations. In this paper, I will give an overview of historical perspective
on barrier rf systems, the longitudinal beam dynamics issues, aspects of rf
linearization to produce long flat bunches and methods used for emittance
measurements of the beam in the RR barrier rf buckets. Current rf manipulation
schemes used for antiproton beam stacking and longitudinal momentum mining of
the RR beam for the Tevatron collider operation are explained along with their
importance in spectacular success of the Tevatron luminosity performance.Comment: 30 pp. Submitted as a chapter in a book on the Tevatron edited by
Valeri Lebedev and Vladimir Shiltse
Status of the LBNE Neutrino Beamline
The Long Baseline Neutrino Experiment (LBNE) will utilize a neutrino beamline
facility located at Fermilab to carry out a compelling research program in
neutrino physics. The facility will aim a beam of neutrinos toward a detector
placed at the Homestake Mine in South Dakota. The neutrinos are produced in a
three-step process. First, protons from the Main Injector (60-120 GeV) hit a
solid target and produce mesons. Then, the charged mesons are focused by a set
of focusing horns into the decay pipe, towards the far detector. Finally, the
mesons that enter the decay pipe decay into neutrinos. The parameters of the
facility were determined taking into account several factors including the
physics goals, the Monte Carlo modeling of the facility, spacial and
radiological constraints and the experience gained by operating the NuMI
facility at Fermilab. The initial beam power is expected to be ~700 kW, however
some of the parameters were chosen to be able to deal with a beam power of 2.3
MW. We discuss here the status of the conceptual design and the associated
challenges.Comment: 6 pages, 3 figure
Physics at a New Fermilab Proton Driver
In 2004, motivated by the recent exciting developments in neutrino physics,
the Fermilab Long Range Planning Committee identified a new high intensity
Proton Driver as an attractive option for the future. At the end of 2004 the
APS ``Study on the Physics of Neutrinos'' concluded that the future U.S.
neutrino program should have, as one of its components, ``A proton driver in
the megawatt class or above and neutrino superbeam with an appropriate very
large detector capable of observing CP violation and measuring the neutrino
mass-squared differences and mixing parameters with high precision''. The
presently proposed Fermilab Proton Driver is designed to accomplish these
goals, and is based on, and would help develop, Linear Collider technology. In
this paper the Proton Driver parameters are summarized, and the potential
physics program is described.Comment: 12 pages, 4 figures. Presented at the III International Workshop on
Neutrino Oscillations in Venice, February 7-10, 200
Top Quark Current Experimental Status
Ten years after its discovery at the Tevatron collider, we still know little
about the top quark. Its large mass suggests it may play a key role in the
mechanism of Electroweak Symmetry Breaking (EWSB), or open a window of
sensitivity to new physics related to EWSB and preferentially coupled to it. To
determine whether this is the case, precision measurements of top quark
properties are necessary. The high statistics samples being collected by the
Tevatron experiments during Run II start to incisively probe the top quark
sector. This report summarizes the experimental status of the top quark,
focusing in particular on the recent measurements from the Tevatron.Comment: 12 pages, 6 figures, 1 table. Talk presented at TOP 2006,
International Workshop on Top Quark Physics, Coimbra, Portugal, January
12-15, 2006. To appear in the proceeding
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