14 research outputs found
Diffractive production of electroweak vector bosons at the LHC
We analyse diffractive electroweak vector boson production in hadronic
collisions and show that the single diffractive W boson production asymmetry in
rapidity is a particularly good observable at the LHC to test the concept of
the flavour symmetric pomeron parton distributions. It may also provide an
additional constraint for the parton distribution functions in the proton.Comment: 7 pages, 5 figure
Charmed Meson Production in Proton - (ANTI)PROTON Collisions
We discuss and compare different approaches to include gluon transverse
momenta for heavy quark-antiquark pair and meson production. The results are
illustrated with the help of different unintegrated gluon distributions (UGDF)
from the literature. We compare results obtained with on-shell and off-shell
matrix elements and kinematics. The results are compared with recent
experimental results of the CDF collaboration.Comment: presented by M. Luszczak at the international conference MESON2006,
June 2006, Cracow, 6 pages, 5 figure
Production of two pairs in double-parton scattering
We discuss production of two pairs of within a simple formalism of
double-parton scattering (DPS). Surprisingly very large cross sections,
comparable to single-parton scattering (SPS) contribution, are predicted for
LHC energies. Both total inclusive cross section as a function of energy and
differential distributions for are shown. We discuss a perspective
how to identify the double scattering contribution.Comment: 8 pages, 6 figure
Early Cenozoic denudation of central west Britain in response to transient and permanent uplift above a mantle plume
Upwelling mantle plumes beneath continental crust are predicted to produce difficult to quantify, modest uplift and denudation. The contribution of permanent and transient components to the uplift is also difficult to distinguish. A pulse of denudation in Britain in the Early Paleogene has been linked, although with some controversy, with the arrival of the proto-Iceland mantle plume. In this contribution we show that combining apatite and zircon (U-Th-Sm)/He and apatite fission track analyses from central west Britain with numerical modeling clearly identifies a pulse of early Cenozoic denudation. The data indicate that rock uplift and denudation were centered on the northern East Irish Sea Basin and 1.0–2.4 km of rocks were removed during the latest Cretaceous-early Paleogene. Uplift and erosion appears to have started a few million years before the earliest magmatism in the region. The regional denudation pattern mirrors the distribution of low-density magmatic rocks that has been imaged in the deep crust. However, the injection of the underplating melt is not enough to account for the total denudation. An additional regional uplift of at least 300 m is required, which is consistent with a transient thermal effect from the hot mantle plume. The rapid exhumation event ceased by ~40 Ma and the data do not require significant Neogene exhumation
The age of the moraine ridges in the eastern part of Fláajökull foreland (SE Iceland) based on the results of lichenometric dating
Wyniki datowania lichenometrycznego trzech wałów morenowych położonych we wschodniej części przedpola lodowca Fláa zostały opracowane w oparciu o pomiary plech Rhizocarpon przy zastosowaniu: i) analizy gradientu rozkładu częstości populacji (GSF), ii) metody największej plechy (LL), iii) metody średniej z pięciu największych plech oraz (5LL) iv) metody pojedynczej przewidywanej plechy (1-IN-1000). Stwierdzono, że maksymalny zasięg lodowca Fláa w małej epoce lodowej przypada na przełom XIX i XX w. Ponadto wykazano niejednorodne tempo recesji czoła lodowca w obrębie jednego lobu oraz wyraźny wpływ warunków mikrośrodowiskowych na liczebność porostów i tempo ich wzrostu.The results of lichenometric dating of Fláajökull moraine ridges located in the eastern part of its marginal zone have been carried out on the base of measurements of the Rhizocarpon thalli and using analyses of: i) the size-frequency distribution gradient (GSF), ii) the largest lichen (LL), iii) the five largest lichens (5LL), and iv) “1-IN-1000” method. It was found that the maximum extent of the glacier in the Little Ice Age occurred at the turn of 19th and 20th centuries. Moreover, the results indicate that the glacier recession rate was not consistent in all parts of the snout and that micro-environmental conditions significantly influence lichen populations and the lichen growth rate