9,099 research outputs found
The CNGS Neutrino Beam
The CERN to Gran Sasso Neutrino beam (CNGS) was commissioned at CERN in early
August 2006 and was first sent at low intensity to Gran Sasso on August 17,
2006. The Borexino, LVD and OPERA experiments continued the commissioning of
their detectors and started taking data with practically no dead time. The CNGS
collected several hundred events with clean time distributions.Comment: 11 pages, 14 EPS figures. Lecture given at the 2nd Latin American
School on Cosmic Rays and Astrophysics, Puebla, Mexico, 30th August - 8th
September 200
Meaurement of Cosmic Ray elemental composition from the CAKE balloon experiment
CAKE (Cosmic Abundances below Knee Energies) was a prototype balloon
experiment for the determination of the charge spectra and of abundances of the
primary cosmic-rays (CR) with Z10. It was a passive instrument made of
layers of CR39 and Lexan nuclear track detectors; it had a geometric acceptance
of 0.7 msr for Fe nuclei. Here, the scanning and analysis strategies,
the algorithms used for the off-line filtering and for the tracking in
automated mode of the primary cosmic rays are presented, together with the
resulting CR charge distribution and their abundances.Comment: 5 pages, 8 figure
Search for nuclearites with the SLIM detector
We discuss the properties of cosmic ray nuclearites, from the point of view
of their search with large nuclear track detector arrays exposed at different
altitudes, in particular with the SLIM experiment at the Chacaltaya high
altitude lab (5290 m a.s.l.). We present calculations concerning their
propagation in the Earth atmosphere and discuss their possible detection with
CR39 and Makrofol nuclear track detectors.Comment: 11 pages, 6 figure
Mining grapevine downy mildew susceptibility genes: A resource for genomics-based breeding and tailored gene editing
Several pathogens continuously threaten viticulture worldwide. Until now, the investigation on resistance loci has been the main trend to understand the interaction between grapevine and the mildew causal agents. Dominantly inherited gene-based resistance has shown to be race-specific in some cases, to confer partial immunity, and to be potentially overcome within a few years since its introgression. Recently, on the footprint of research conducted in Arabidopsis, putative genes associated with downy mildew susceptibility have been discovered also in the grapevine genome. In this work, we deep-sequenced four putative susceptibility genes\u2014namely VvDMR6.1, VvDMR6.2, VvDLO1, VvDLO2\u2014in 190 genetically diverse grapevine genotypes to discover new sources of broad-spectrum and recessively inherited resistance. Identified Single Nucleotide Polymorphisms were screened in a bottleneck analysis from the genetic sequence to their impact on protein structure. Fifty-five genotypes showed at least one impacting mutation in one or more of the scouted genes. Haplotypes were inferred for each gene and two of them at the VvDMR6.2 gene were found significantly more represented in downy mildew resistant genotypes. The current results provide a resource for grapevine and plant genetics and could corroborate genomic-assisted breeding programs as well as tailored gene editing approaches for resistance to biotic stresses
Fragmentation cross sections of Fe^{26+}, Si^{14+} and C^{6+} ions of 0.3-10 A GeV on CR39, polyethylene and aluminum targets
New measurements of the total and partial fragmentation cross sections in the
energy range 0.3-10 A GeV of Fe^{26+}, Si^{14+} and C^{6+} beams on
polyethylene, CR39 and aluminum targets are presented. The exposures were made
at Brookhaven National Laboratory (BNL), USA, and Heavy Ion Medical Accelerator
in Chiba (HIMAC), Japan. The CR39 nuclear track detectors were used to identify
the incident and survived beams and their fragments. The total fragmentation
cross sections for all targets are almost energy independent while they depend
on the target mass. The measured partial fragmentation cross sections are also
discussed.Comment: 4 pages, 5 eps figures. Talk given at the 24th International
Conference on Nuclear Tracks in Solids, Bologna, Italy, 1-5 September 200
On the K^+D Interaction at Low Energies
The Kd reactions are considered in the impulse approximation with NN
final-state interactions (NN FSI) taken into account. The realistic parameters
for the KN phase shifts are used. The "quasi-elastic" energy region, in which
the elementary KN interaction is predominantly elastic, is considered. The
theoretical predictions are compared with the data on the K^+d->K^+pn,
K^+d->K^0pp, K^+d->K^+d and K^+d total cross sections. The NN FSI effect in the
reaction K^+d->K^+pn has been found to be large. The predictions for the Kd
cross sections are also given for slow kaons, produced from phi(1020) decays,
as the functions of the isoscalar KN scattering length a_0. These predictions
can be used to extract the value of a_0 from the data.Comment: 22 pages, 5 figure
Cosmic ray abundance measurements with the CAKE balloon experiment
We present the results from the CAKE (Cosmic Abundance below Knee Energy)
balloon experiment which uses nuclear track detectors. The final experiment
goal is the determination of the charge spectrum of CR nuclei with Z > 30 in
the primary cosmic radiation. The detector, which has a geometric acceptance of
\~ 1.7 m2 sr, was exposed in a trans-mediterranean stratospheric balloon
flight. Calibrations of the detectors used (CR39 and Lexan), scanning
strategies and algorithms for tracking particles in an automatic mode are
presented. The present status of the results is discussedComment: 5 pages, 3 figures, proceeding to 29 ICRC, 2005, Pune Indi
Magnetic Monopoles As a New Solution to Strong CP Problem
A non-perturbative solution to strong CP problem is proposed. It is shown
that the gauge orbit space with gauge potentials and gauge tranformations
restricted on the space boundary in non-abelian gauge theories with a
term has a magnetic monopole structure if there is a magnetic monopole in the
ordinary space. The Dirac's quantization condition in the corresponding quantum
theories ensures that the vacuum angle in the gauge theories must be
quantized. The quantization rule is derived as with n
being the topological charge of the magnetic monopole. Therefore, we conclude
that the strong CP problem is automatically solved non-perturbatively with the
existence of a magnetic monopole of charge with . This
is also true when the total magnetic charge of monopoles are very large
() if it is consistent with the abundance of magnetic
monopoles. This implies that the fact that the strong CP violation can be only
so small or vanishing may be a signal for the existence of magnetic monopoles.Comment: LBL-32491, June, 199
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