6,248 research outputs found
Quark resonances and high E_t jets
Possible spin-3/2 quark resonances would have a significant effect on high
E_{\mbox{\rm t}} jet production through their contribution to the subprocess
. Such enhancements are compared to a, recently
reported, anomaly in inclusive jet production at the CDF detector.Comment: 7 pages set in RevTex with four postscript figures appended- all
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Vector Boson Pair Production in Hadronic Collisions at Order : Lepton Correlations and Anomalous Couplings
We present cross sections for production of electroweak vector boson pairs,
, and , in and collisions, at next-to-leading
order in . We treat the leptonic decays of the bosons in the
narrow-width approximation, but retain all spin information via decay angle
correlations. We also include the effects of and anomalous
couplings.Comment: 23 pages, 8 figures, 3 table
Higher-order QED corrections to W-boson mass determination at hadron colliders
The impact of higher-order final-state photonic corrections on the precise
determination of the W-boson mass at the Tevatron and LHC colliders is
evaluated. In the presence of realistic selection criteria, the shift in the W
mass from a fit to the transverse mass distribution is found to be about 10 MeV
in the channel and almost negligible in the
channel. The calculation, which is implemented in a Monte Carlo event generator
for data analysis, can contribute to reduce the uncertainty associated to the W
mass measurement at future hadron collider experiments.Comment: 9 pages, 2 figures, 1 table, RevTe
Effect of Carbohydrate Demand on the Remobilization of Starch in Stolons and Roots of White Clover (Trifolium repens L.) after Defoliation
White clover plants were grown from stolon tips in growth cabinets and then defoliated. Thereafter, changes in the contents of non-structural carbohydrates such as starch, sucrose, glucose, fructose, maltose, and pinitol in stolons and roots were monitored. Initial contents of carbohydrate reserves, photosynthetic supply of new carbohydrates and carbohydrate demand after defoliation were varied by growing the plants at various CO2 partial pressures, by varying the extent of defoliation and by removing either roots or stolon tips at the time of defoliation. Remobilization of carbohydrate reserves in stolons increased proportionally to their initial contents and was greater when plants had been severely defoliated, suggesting that carbohydrates were remobilized according to availability and demand. Starch was the predominant reserve carbohydrate. Starch degradation was associated with decreased contents of sucrose, glucose and fructose in young stolon parts and roots but not in old stolon parts suggesting that starch degradation was not strictly controlled by the contents of these sugars. A decrease in the demand for carbohydrates by removal of roots did not decrease starch degradation but increased the contents of sucrose, glucose, and fructose. Removal of stolon tips decreased starch degradation and contents of sucrose, glucose, and fructose. The results suggest that starch degradation was controlled by a factor other than sucrose, glucose, and fructose which was exported from stolon tips, e.g. gibberelli
The Semiclassical Coulomb Interaction
The semiclassical Coulomb excitation interaction is at times expressed in the
Lorentz gauge in terms of the electromagnetic fields and a contribution from
the scalar electric potential. We point out that the potential term can make
spurious contributions to excitation cross sections, especially when the the
decay of excited states is taken into account. We show that, through an
appropriate gauge transformation, the excitation interaction can be expressed
in terms of the electromagnetic fields alone.Comment: 12 pages. Phys. Rev. C, Rapid Communication, in pres
Two Photon Radiation in W and Z Boson Production at the Tevatron Collider
We present a calculation of two photon radiation in W and Z boson production
in hadronic collisions, based on the complete matrix elements for the processes
q\bar q'\to\ell^\pm\nu\gamma\gamma and q\bar q\to\ell^+\ell^-\gamma\gamma,
including finite charged lepton masses. In order to achieve stable numerical
results over the full phase space, multiconfiguration Monte Carlo techniques
are used to map the peaks in the differential cross section. Numerical results
are presented for the Fermilab Tevatron.Comment: Revtex, 28 pages, 3 figure
Hadronic Production with QCD Corrections and Leptonic Decays
The process , where
denotes a lepton, is calculated to order . Total and differential
cross sections, with acceptance cuts imposed on the leptons and photon, are
given for the Tevatron and LHC center of mass energies. In general, invariant
mass and angular distributions are simply scaled up in magnitude by the QCD
radiative corrections, whereas in transverse momentum distributions, the QCD
radiative corrections increase with the transverse momentum.Comment: 16 pages + 9 figures, UCD-94-29. A postscript version and 9
postscript figures are available via anonymous ftp to UCDHEP.UCDAVIS.EDU in
the directory [.ohnemus.ucd-94-29
Electroweak-correction effects in gauge-boson pair production at the LHC
We have studied the effect of one-loop logarithmic electroweak radiative
corrections on WZ and production processes at the LHC. We present
analytical results for the leading-logarithmic electroweak corrections to the
corresponding partonic processes du -> WZ, Wgamma. Using the leading-pole
approximation we implement these corrections into Monte Carlo programs for
. We find that electroweak corrections
lower the predictions by 5-20% in the physically interesting region of large
transverse momentum and small rapidity separation of the gauge bosons.Comment: 28 pages, LaTex, 13 eps figures included; references added and
corrected typo
Top effective operators at the ILC
We investigate the effect of top trilinear operators in t tbar production at
the ILC. We find that the sensitivity to these operators largely surpasses the
one achievable by the LHC either in neutral or charged current processes,
allowing to probe new physics scales up to 4.5 TeV for a centre of mass energy
of 500 GeV. We show how the use of beam polarisation and an eventual energy
upgrade to 1 TeV allow to disentangle all effective operator contributions to
the Ztt and gamma tt vertices.Comment: LaTeX 13 pages. Typos corrected. Final version in JHE
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