16,171 research outputs found
Search for Long-lived Charged Massive Particles at CDF
A search for long-lived charged massive particles in CDF's Run1b data sample
is presented. The search looks for highly ionizing tracks which would result
from slowly moving massive particles. We search for strongly produced particles
using a stable color triplet quark as a reference model, and a separate search
was performed for weakly produced particles using long-lived sleptons in Gauge
Mediated Supersymmetry Breaking as a reference model. No excess over background
was observed, and we derive limits on the cross-sections for production of
these particles. Prospects for RunII are also discussed.Comment: Talk given at the DPF99 Conference on January 6, 1999. 5 pages, 4
figures, Late
Towards More Precise Photometric Redshifts: Calibration Via CCD Photometry
We present the initial results from a deep, multi-band photometric survey of
selected high Galactic latitude redshift fields. Previous work using the
photographic data of Koo and Kron demonstrated that the distribution of
galaxies in the multi-dimensional flux space U B R I is nearly planar. The
position of a galaxy within this plane is determined by its redshift,
luminosity and spectral type. Using recently acquired deep CCD photometry in
existing, published redshift fields, we have redetermined the distribution of
galaxies in this four-dimensional magnitude space. Furthermore, from our CCD
photometry and the published redshifts, we have quantified the
photometric-redshift relation within the standard AB magnitude system. This
empirical relation has a measured dispersion of approximately 0.02 for z < 0.4.
With this work we are reaching the asymptotic intrinsic dispersions that were
predicted from simulated distributions of galaxy colors.Comment: submitted to the Astrophysical Journal Letter
Galactic extinction and Abell clusters
In this paper, we present the results of comparing the angular distribution
of Abell clusters with Galactic HI measurements. For most subsamples of
clusters considered, their positions on the sky appear to be anti-correlated
with respect to the distribution of HI column densities. The statistical
significance of these observed anti-correlations is a function of both richness
and distance class, with the more distant and/or richest systems having the
highest significance (~3 sigma). The lower richness, nearby clusters appear to
be randomly distributed compared to the observed Galactic HI column density.Comment: 5 pages, uuencoded compressed postscript file. Figures included.
Accepted by MNRA
Triterpenoids
This review covers the isolation and structure determination of triterpenoids reported during 2012 including squalene derivatives, lanostanes, holostanes, cycloartanes, cucurbitanes, dammaranes, euphanes, tirucallanes, tetranortriterpenoids, quassinoids, lupanes, oleananes, friedelanes, ursanes, hopanes, serratanes, isomalabaricanes and saponins; 348 references are cited
Search for MSSM Higgses at the Tevatron
We present an overview of searches for MSSM Higgs at the Tevatron,
concentrating on searches probing the high tan(beta) region. We discuss the
search for A/H -> tau tau which is soon to be completed in the Run I data and
review the new tau triggers implemented by CDF and D0 in Run II, which will
greatly impact this analysis. We also present the results of a Run I search for
A/H bb -> bbbb performed by CDF and highlight expected improvements in this
channel by both experiments in Run II.Comment: 3 pages with 1 figure, to be published in "Proceedings of the 31st
International Conference on High Energy Physics ICHEP 2002
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