1,870 research outputs found
Precision measurements from the NOMAD experiment
The NOMAD experiment collected unprecedent neutrino data samples, matching
both the large statistics of massive calorimeters and the reconstruction
quality of bubble chambers. This paper describes the determination of the weak
mixing angle which is ongoing in NOMAD, with a target precision of .
In addition, measurements of the quasi-elastic cross-section and of
neutrino Charged Current differential cross-section on carbon are presented.Comment: 4 pages, 3 figures. To appear in the proceedings of the 32nd
International Conference on High-Energy Physics (ICHEP04), Beijing, China,
16-22 Aug 200
A preliminary assessment of the accuracy of selected meteorological parameters determined from Nimbus 6 satellite profile data
Published rms errors in rawinsonde data and discrepancies between satellite and rawinsonde profile data for temperature, dewpoint temperature, mixing ratio, and wind speed. Satellite rms errors were found to be 2 to 3 times as large as those for rawinsonde data. Gradients of the preceding parameters were computed for both rawinsonde and satellite data and compared with means and near extreme values computed from the AVE 2 and AVE 4 experiments. In all cases, it was found that satellite data can be used to determine with relatively good accuracy the near extreme gradients but not those whose value does not exceed the average. Synoptic charts were prepared to show that patterns of temperature could be determined with relatively good accuracy, while those of dew point were not as good as those for temperature. Winds represented by cloud motion vectors (satellite winds) were compared with rawinsonde winds, and it was found that large gaps exist in satellite values for a given pressure level and that errors in the satellite determined concluded that satellite profile data are very useful in synoptic analysis, particularly in data sparse regions as well as regions where near extreme gradients exist in the measured parameters
Structure functions for light nuclei
We discuss the nuclear EMC effect with particular emphasis on recent data for
light nuclei including 2H, 3He, 4He, 9Be, 12C and 14N. In order to verify the
consistency of available data, we calculate the \chi^2 deviation between
different data sets. We find a good agreement between the results from the NMC,
SLAC E139, and HERMES experiments. However, our analysis indicates an overall
normalization offset of about 2% in the data from the recent JLab E03-103
experiment with respect to previous data for nuclei heavier than 3He. We also
discuss the extraction of the neutron/proton structure function ratio F2n/F2p
from the nuclear ratios 3He/2H and 2H/1H. Our analysis shows that the E03-103
data on 3He/2H require a renormalization of about 3% in order to be consistent
with the F2n/F2p ratio obtained from the NMC experiment. After such a
renormalization, the 3He data from the E03-103 data and HERMES experiments are
in a good agreement. Finally, we present a detailed comparison between data and
model calculations, which include a description of the nuclear binding, Fermi
motion and off-shell corrections to the structure functions of bound proton and
neutron, as well as the nuclear pion and shadowing corrections. Overall, a good
agreement with the available data for all nuclei is obtained.Comment: 18 pages, 7 figures, 5 tables, final version published in Phys. Rev.
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