13,504 research outputs found
Search for Deeply Bound Kaonic Nuclear States with AMADEUS
We briefly report on the search for Deeply Bound Kaonic Nuclear States with
AMADEUS in the Sigma0 p channel following K- absorption on 12C and outline
future perspectives for this work
Potential of mathematical modeling in fruit quality
A review of mathematical modeling applied to fruit quality showed that these models ranged inresolution from simple yield equations to complex  representations of processes as respiration, photosynthesis and assimilation of nutrients. The latter models take into account complex  genotype environment interactions to estimate their effects on growth and yield. Recently, models are used to estimate seasonal changes in quality traits as fruit size, dry matter, water content and the concentration of sugars and acids, which are very important for flavor and aroma. These models have demonstrated their ability to generate relationships between physiological variables and quality attributes (allometric relations). This new kind of hybrid models has sufficient complexity to predict quality traits behavior
Supergravity brane worlds and tachyon potentials
We study massless and massive graviton modes that bind on thick branes which
are supergravity domain walls solutions in -dimensional supergravity
theories where only the supergravity multiplet and the scalar supermultiplet
are turned on. The domain walls are bulk solutions provided by tachyon
potentials. Such domain walls are regarded as BPS branes of one lower dimension
that are formed due to tachyon potentials on a non-BPS D-brane.Comment: RevTex4, 6 pages; version to appear in Phys. Rev.
Shedding New Light on Kaon-Nucleon/Nuclei Interaction and Its Astrophysical Implications with the AMADEUS Experiment at DAFNE
The AMADEUS experiment deals with the investigation of the low-energy
kaon-nuclei hadronic interaction at the DA{\Phi}NE collider at LNF-INFN, which
is fundamental to respond longstanding questions in the non-perturbative QCD
strangeness sector. The antikaon-nucleon potential is investigated searching
for signals from possible bound kaonic clusters, which would open the
possibility for the formation of cold dense baryonic matter. The confirmation
of this scenario may imply a fundamental role of strangeness in astrophysics.
AMADEUS step 0 consisted in the reanalysis of 2004/2005 KLOE dataset,
exploiting K- absorptions in H, 4He, 9Be and 12C in the setup materials. In
this paper, together with a review on the multi-nucleon K- absorption and the
particle identification procedure, the first results on the {\Sigma}0-p channel
will be presented including a statistical analysis on the possible accomodation
of a deeply bound stateComment: 6 pages, 2 figure, 1 table, HADRON 2015 conferenc
Effects of epitaxial strain on the growth mechanism of YBa2Cu3O7-x thin films in [YBa2Cu3O7-x / PrBa2Cu3O7-x] superlattices
We report on the growth mechanism of YBa2Cu3O7-x (YBCO). Our study is based
on the analysis of ultrathin, YBa2Cu3O7-x layers in c-axis oriented YBa2Cu3O7-x
/ PrBa2Cu3O7-x superlattices. We have found that the release of epitaxial
strain in very thin YBCO layers triggers a change in the dimensionality of the
growth mode. Ultrathin, epitaxially strained, YBCO layers with thickness below
3 unit cells grow in a block by block two dimensional mode coherent over large
lateral distances. Meanwhile, when thickness increases, and the strain relaxes,
layer growth turns into three dimensional, resulting in rougher layers and
interfaces.Comment: 10 pages + 9 figures, accepted in Phys. Rev.
The initial stellar mass function from random sampling in hierarchical clouds II: statistical fluctuations and a mass dependence for starbirth positions and times
Observed variations in the slope of the initial stellar mass function are
shown to be consistent with a model in which the protostellar gas is randomly
sampled from hierarchical clouds at a rate proportional to the square root of
the local density. RMS variations in the IMF slope around the Salpeter value
are +/- 0.4 when only 100 stars are observed, and +/- 0.1 when 1000 stars are
observed. The hierarchical-sampling model also reproduces the tendency for
massive stars to form closer to the center of a cloud, at a time somewhat later
than the formation time of the lower mass stars. The assumed density dependence
for the star formation rate is shown to be appropriate for turbulence
compression, magnetic diffusion, gravitational collapse, and clump or
wavepacket coalescence. The low mass flattening in the IMF comes from the
inability of gas to form stars below the thermal Jeans mass at typical
temperatures and pressures. Consideration of heating and cooling processes
indicate why the thermal Jeans mass should be nearly constant in normal
environments, and why it might increase in some starburst regions. The steep
IMF in the extreme field is not explained by the model, but other origins are
suggested.Comment: 21 pages, 8 figures, scheduled for ApJ vol. 515, April 10, 199
Unprecedented studies of the low-energy negatively charged kaons interactions in nuclear matter by AMADEUS
The AMADEUS experiment aims to provide unique quality data of hadronic
interactions in light nuclear targets, in order to solve fundamental open
questions in the non-perturbative strangeness QCD sector, like the
controversial nature of the state, the yield of hyperon
formation below threshold, the yield and shape of multi-nucleon
absorption, processes which are intimately connected to the possible existence
of exotic antikaon multi-nucleon clusters. AMADEUS takes advantage of the
DANE collider, which provides a unique source of monochromatic
low-momentum kaons and exploits the KLOE detector as an active target, in order
to obtain excellent acceptance and resolution data for nuclear capture on
H, He, Be and C, both at-rest and in-flight. During the
second half of 2012 a successful data taking was performed with a dedicated
pure carbon target implemented in the central region of KLOE, providing a high
statistic sample of pure at-rest nuclear interactions. For the future
dedicated setups involving cryogenic gaseous targets are under preparation.Comment: 14 pages, 6 figure
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