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Parton distributions
I discuss our current understanding of parton distributions. I begin with the underlying theoretical framework, and the way in which different data sets constrain different partons, highlighting recent developments. The methods of examining the uncertainties on the distributions and those physical quantities dependent on them is analyzed. Finally I look at the evidence that additional theoretical corrections beyond NLO perturbative QCD may be necessary, what type of corrections are indicated and the impact these may have on the uncertainties.</jats:p
Heavy Quark Production and PDF's Subgroup Report
We present a status report of a variety of projects related to heavy quark
production and parton distributions for the Tevatron Run II.Comment: Latex. 8 pages, 7 eps figures. Contribution to the Physics at Run II
Workshops: QCD and Weak Boson Physic
Report of the QCD Tools Working Group
We report on the activities of the ``QCD Tools for heavy flavors and new
physics searches'' working group of the Run II Workshop on QCD and Weak Bosons.
The contributions cover the topics of improved parton showering and comparisons
of Monte Carlo programs and resummation calculations, recent developments in
Pythia, the methodology of measuring backgrounds to new physics searches,
variable flavor number schemes for heavy quark electro-production, the
underlying event in hard scattering processes, and the Monte Carlo MCFM for NLO
processes.Comment: LaTeX, 47 pages, 41 figures, 10 tables, uses run2col.sty, to appear
in the Proceedings of the Workshop on "QCD and Weak Boson Physics in Run II",
Fermilab, March - November 199
An Algorithm to locate the centers of Baryon Acoustic Oscillations
The cosmic structure formed from Baryon Acoustic Oscillations (BAO) in the
early universe is imprinted in the galaxy distribution observable in large
scale surveys, and is used as a standard ruler in contemporary cosmology. BAO
are typically detected as a preferential length scale in two point statistics,
which gives little information about the location of BAO structures in real
space. The aim of the algorithm described in this paper is to find probable
centers of BAO in the cosmic matter distribution. The algorithm convolves the
three dimensional distribution of matter density with a spherical shell kernel
of variable radius placed at different locations. The locations that correspond
to the highest values of the convolution correspond to the probable centers of
BAO. This method is realized in an open-source, computationally efficient
algorithm. We describe the algorithm and present the results of applying it to
the SDSS DR9 CMASS survey and associated mock catalogs. A detailed performance
study demonstrates the algorithm's ability to locate BAO centers, and in doing
so presents a novel detection of the BAO scale in galaxy surveys.Comment: 8 pages, 13 figure
Meromorphic traveling wave solutions of the complex cubic-quintic Ginzburg-Landau equation
We look for singlevalued solutions of the squared modulus M of the traveling
wave reduction of the complex cubic-quintic Ginzburg-Landau equation. Using
Clunie's lemma, we first prove that any meromorphic solution M is necessarily
elliptic or degenerate elliptic. We then give the two canonical decompositions
of the new elliptic solution recently obtained by the subequation method.Comment: 14 pages, no figure, to appear, Acta Applicandae Mathematica
Synthesis of aryl-substituted thieno[3,2-b]thiophene derivatives and their use for N,S-heterotetracene construction
Fiesselmann thiophene synthesis was applied for the convenient construction of thieno[3,2-b]thiophene derivatives. Thus, new 5- or 6-aryl-3-hydroxythieno[3,2-b]thiophene-2-carboxylates were obtained by condensation of 5- or 4-aryl-3-chlorothiophene-2-carbox-ylates, respectively, with methyl thioglycolate in the presence of potassium tert-butoxide. The saponification of the resulting esters, with decarboxylation of the intermediating acids, gave the corresponding thieno[3,2-b]thiophen-3(2H)-ones. The latter ketones were used to synthesize new N,S-heterotetracenes, namely 9H-thieno[2',3':4,5]thieno[3,2-b]indoles by their treatment with arylhydrazines in accordance with the Fischer indolization reaction. © 2019 Demina et al.; licensee Beilstein-Institut.Russian Foundation for Basic Research, RFBR: 18-33-20083This study was supported by the Russian Foundation for Basic Research, Grant No. 18-33-20083
Parton Distributions Working Group
The main focus of this working group was to investigate the different issues
associated with the development of quantitative tools to estimate parton
distribution functions uncertainties. In the conclusion, we introduce a
"Manifesto" that describes an optimal method for reporting data.Comment: Report of the Parton Distributions Working Group of the 'QCD and Weak
Boson Physics workshop in preparation for Run II at the Fermilab Tevatron'.
Co-Conveners: L. de Barbaro, S.A. Keller, S. Kuhlmann, H. Schellman, and
W.-K. Tun
The Reach of the Fermilab Tevatron and CERN LHC for Gaugino Mediated SUSY Breaking Models
In supersymmetric models with gaugino mediated SUSY breaking (inoMSB), it is
assumed that SUSY breaking on a hidden brane is communicated to the visible
brane via gauge superfields which propagate in the bulk. This leads to GUT
models where the common gaugino mass is the only soft SUSY breaking
term to receive contributions at tree level. To obtain a viable phenomenology,
it is assumed that the gaugino mass is induced at some scale beyond the
GUT scale, and that additional renormalization group running takes place
between and as in a SUSY GUT. We assume an SU(5) SUSY GUT above
the GUT scale, and compute the SUSY particle spectrum expected in models with
inoMSB. We use the Monte Carlo program ISAJET to simulate signals within the
inoMSB model, and compute the SUSY reach including cuts and triggers approriate
to Fermilab Tevatron and CERN LHC experiments. We find no reach for SUSY by the
Tevatron collider in the trilepton channel. %either with or without %identified
tau leptons. At the CERN LHC, values of (1160) GeV can be probed
with 10 (100) fb of integrated luminosity, corresponding to a reach in
terms of of 2150 (2500) GeV. The inoMSB model and mSUGRA can likely
only be differentiated at a linear collider with sufficient energy to
produce sleptons and charginos.Comment: 17 page revtex file with 9 PS figure
Prospect for Searches for Gluinos and Squarks at a Tevatron Tripler
We examine the discovery potential for SUSY new physics at a p{\bar p}
collider upgrade of Tevatron with \sqrt s = 5.4 TeV and luminosity L ~= 4\times
10^{32} cm^{-2}s^{-1} (the Tripler). We consider the reach for gluinos and
squarks using the experimental signatures with large missing transverse energy
(\met) of jets + \met and 1l + jets + \met (where l=electron or muon) within
the framework of minimal supergravity. The Tripler's strongest reach for the
gluino is 1060 GeV for the jets + \met channel and 1140 GeV for the 1l + jets +
\met channel for 30 fb^{-1} of integrated luminosity (approximately two years
running time). This is to be compared with the Tevatron where the reach is
440(460) GeV in the jets + \met channel for 15(30) fb^{-1} of integrated
luminosity.Comment: 17 pages, latex, 7 figure
200 mm Sensor Development Using Bonded Wafers
Sensors fabricated from high resistivity, float zone, silicon material have
been the basis of vertex detectors and trackers for the last 30 years. The
areas of these devices have increased from a few square cm to for
the existing CMS tracker. High Luminosity Large Hadron Collider (HL-LHC), CMS
and ATLAS tracker upgrades will each require more than of silicon
and the CMS High Granularity Calorimeter (HGCAL) will require more than $600\
m^2200 mm$ wafers using wafer bonding technology. Results of development runs
with float zone, Silicon-on-Insulator and Silicon-Silicon bonded wafer
technologies are reported.Comment: 11 page
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