13,656 research outputs found
Research on the application of satellite remote sensing to local, state, regional, and national programs involved with resource management and environmental quality
Project summaries and project reports are presented in the area of satellite remote sensing as applied to local, regional, and national environmental programs. Projects reports include: (1) Douglas County applications program; (2) vegetation damage and heavy metal concentration in new lead belt; (3) evaluating reclamation of strip-mined land; (4) remote sensing applied to land use planning at Clinton Reservoir; and (5) detailed land use mapping in Kansas City, Kansas
Role of oxygen in the electron-doped superconducting cuprates
We report on resistivity and Hall measurements in thin films of the
electron-doped superconducting cuprate PrCeCuO.
Comparisons between x = 0.17 samples subjected to either ion-irradiation or
oxygenation demonstrate that changing the oxygen content has two separable
effects: 1) a doping effect similar to that of cerium, and 2) a disorder
effect. These results are consistent with prior speculations that apical oxygen
removal is necessary to achieve superconductivity in this compound.Comment: 5 pages, 5 figure
Simple supersymmetric solution to the strong CP problem
It is shown that the minimal supersymmetric left-right model can provide a
natural solution to the strong {\it CP} problem without the need for an axion,
nor any additional symmetries beyond supersymmetry and parity.Comment: Plain Latex. 10 pages, including two figures which are part of the
Latex file. Shortened version, to appear in Phys. Rev. Lett. 7
Transverse mass and invariant mass observables for measuring the mass of a semi-invisibly decaying heavy particle
Formulae are derived for the positions of end-points in the invariant mass
and transverse mass distributions obtained from the products of heavy states
decaying to pairs of semi-invisibly decaying lighter states. Formulae are
derived both for the special case where the two decay chains are identical and
the more general case where they are different. The formulae are tested with a
simple case study of heavy SUSY higgs particles decaying to gauginos at the
LHC.Comment: 13 pages, 8 eps figure
SUSY and Dark Matter Constraints from the LHC
The ability of the LHC to make statements about the dark matter problem is
considered, with a specific focus on supersymmetry. After reviewing the current
strategies for supersymmetry searches at the LHC (in both CMS and ATLAS), some
key ATLAS studies are used to demonstrate how one could establish that SUSY
exists before going on to measure the relic density of a neutralino WIMP
candidate. Finally, the general prospects for success at the LHC are
investigated by looking at different points in the MSSM parameter space.Comment: Talk given at the XLIrst Rencontres de Moriond session devoted to
Electroweak Interactions And Unified Theories in March 2006, to be published
in the associated proceedings. 10 pages, 8 figure
A hybrid method for determining particle masses at the Large Hadron Collider with fully identified cascade decays
A new technique for improving the precision of measurements of SUSY particle
masses at the LHC is introduced. The technique involves kinematic fitting of
events with two fully identified decay chains. We incorporate both event ETmiss
constraints and independent constraints provided by kinematic end-points in
experiment invariant mass distributions of SUSY decay products. Incorporation
of the event specific information maximises the information used in the fit and
is shown to reduce the mass measurement uncertainites by ~30% compared to
conventional fitting of experiment end-point constraints for the SPS1a
benchmark model.Comment: 10 pages, 2 .eps figures, JHEP3 styl
Supersymmetric particle mass measurement with the boost-corrected contransverse mass
A modification to the contransverse mass (MCT) technique for measuring the
masses of pair-produced semi-invisibly decaying heavy particles is proposed in
which MCT is corrected for non-zero boosts of the centre-of-momentum (CoM)
frame of the heavy states in the laboratory transverse plane. Lack of knowledge
of the mass of the CoM frame prevents exact correction for this boost, however
it is shown that a conservative correction can nevertheless be derived which
always generates an MCT value which is less than or equal to the true value of
MCT in the CoM frame. The new technique is demonstrated with case studies of
mass measurement with fully leptonic ttbar events and with SUSY events
possessing a similar final state.Comment: 33 pages, 33 .eps figures, JHEP3 styl
Simultaneous Ultraviolet and X-ray Observations of the Seyfert Galaxy NGC 4151. II. Physical Conditions in the UV Absorbers
We present a detailed analysis of the intrinsic absorption in the Seyfert 1
galaxy NGC 4151 using UV spectra from the HST/STIS and FUSE, obtained 2002 May
as part of a set of contemporaneous observations that included Chandra/HETGS
spectra. In our analysis of the Chandra spectra, we determined that the soft
X-ray absorber was the source of the saturated UV lines of O VI, C IV, and N V
associated with the absorption feature at a radial velocity of ~ -500 km/sec,
which we referred to as component D+E. In the present work, we have derived
tighter constrains on the the line-of-sight covering factors, densities, and
radial distances of the absorbers. We find that the Equivalent Widths (EWs) of
the low-ionization lines associated with D+E varied over the period from 1999
July to 2002 May. The drop in the EWs of these lines between 2001 April and
2002 May are suggestive of bulk motion of gas out of our line-of-sight. If
these lines from these two epochs arose in the same sub-component, the
transverse velocity of the gas is ~ 2100 km/sec. Transverse velocities of this
order are consistent with an origin in a rotating disk, at the roughly radial
distance we derived for D+E.Comment: 51 pages, including 12 figures. Accepted for publication in ApJ
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