685 research outputs found
Effect of Diet on Mortality and Larval Duration in Chrysodeixis includens (Lepidoptera: Noctuidae)
Diet mediates many life history trade-offs and therefore is an important environmental component to consider. Because some organisms share food sources with humans, they encounter anthropogenic changes to their diet, such as genetically modified crops and chemical applications, which can contribute to additional complexity in their environment. To understand the effect of diet on the life history of the soybean looper, Chrysodeixis includens, we exposed larvae to several different food sources, including genetically modified soybean leaves and the pesticide spinosad. Significant differences in larval instar duration and timing of larval mortality among treatments were observed indicating that type of diet has complex effects on the life history of C. includens
MesonNet 2013 International Workshop. Mini-proceedings
The mini-proceedings of the MesonNet 2013 International Workshop held in
Prague from June 17th to 19th, 2013, are presented. MesonNet is a research
network within EU HadronPhysics3 project (1/2012 -- 12/2014). The web page of
the conference, which contains all talks, can be found at
http://ipnp.mff.cuni.cz/mesonnet13Comment: 106 pages, 53 contributions. Mini-proceedings of the MesonNet 2013
International Workshop. Editors: K. Kampf, A. Kupsc, and P. Masjua
Origin of the low-mass electron pair excess in light nucleus-nucleus collisions
We report measurements of electron pair production in elementary p+p and d+p
reactions at 1.25 GeV/u with the HADES spectrometer. For the first time, the
electron pairs were reconstructed for n+p reactions by detecting the proton
spectator from the deuteron breakup. We find that the yield of electron pairs
with invariant mass Me+e- > 0.15 GeV/c2 is about an order of magnitude larger
in n+p reactions as compared to p+p. A comparison to model calculations
demonstrates that the production mechanism is not sufficiently described yet.
The electron pair spectra measured in C+C reactions are compatible with a
superposition of elementary n+p and p+p collisions, leaving little room for
additional electron pair sources in such light collision systems.Comment: 11 pages, 2 figures, \usepackage{epsfig
Production of Sigma{\pm}pi?pK+ in p+p reactions at 3.5 GeV beam energy
We study the production of Sigma^+-pi^+-pK^+ particle quartets in p+p
reactions at 3.5 GeV kinetic beam energy. The data were taken with the HADES
experiment at GSI. This report evaluates the contribution of resonances like
Lambda(1405$, Sigma(1385)^0, Lambda(1520), Delta(1232), N^* and K^*0 to the
Sigma^+- pi^-+ p K+ final state. The resulting simulation model is compared to
the experimental data in several angular distributions and it shows itself as
suitable to evaluate the acceptance corrections properly.Comment: 15 pages, 5 figure
An upper limit on hypertriton production in collisions of Ar(1.76 AGeV)+KCl
A high-statistic data sample of Ar(1.76 AGeV)+KCl events recorded with HADES
is used to search for a hypertriton signal. An upper production limit per
centrality-triggered event of x on the level is
derived. Comparing this value with the number of successfully reconstructed
hyperons allows to determine an upper limit on the ratio
, which is confronted with statistical and
coalescence-type model calculations
In-Medium Effects on K0 Mesons in Relativistic Heavy-Ion Collisions
We present the transverse momentum spectra and rapidity distributions of
and K in Ar+KCl reactions at a beam kinetic energy of 1.756 A
GeV measured with the spectrometer HADES. The reconstructed K sample is
characterized by good event statistics for a wide range in momentum and
rapidity. We compare the experimental and K distributions to
predictions by the IQMD model. The model calculations show that K at low
tranverse momenta constitute a particularly well suited tool to investigate the
kaon in-medium potential. Our K data suggest a strong repulsive in-medium
K potential of about 40 MeV strength.Comment: 10 pages, 10 figures, accepted by Phys. Rev.
The interaction studied via femtoscopy in p + Nb reactions at
We report on the first measurement of and correlations via
the femtoscopy method in p+Nb reactions at , studied with the High Acceptance Di-Electron Spectrometer
(HADES). By comparing the experimental correlation function to model
calculations, a source size for pairs of and a slightly
smaller value for of is extracted.
Using the geometrical extent of the particle emitting region, determined
experimentally with correlations as reference together with a source
function from a transport model, it is possible to study different sets of
scattering parameters. The correlation is proven sensitive to
predicted scattering length values from chiral effective field theory. We
demonstrate that the femtoscopy technique can be used as valid alternative to
the analysis of scattering data to study the hyperon-nucleon interaction.Comment: 12 pages, 11 figure
Baryonic resonances close to the Kbar-N threshold: the case of Sigma(1385)^+ in pp collisions
We present results of an exclusive measurement of the first excited state of
the Sigma hyperon, Sigma(1385)^+, produced in p+p -> Sigma^+ + K^+ + n at 3.5
GeV beam energy. The extracted data allow to study in detail the invariant mass
distribution of the Sigma(1385)^+. The mass distribution is well described by a
relativistic Breit-Wigner function with a maximum at m_0 = 1383.2 +- 0.9
MeV/c^2 and a width of 40.2 +- 2.1 MeV/c^2. The exclusive production
cross-section comes out to be 22.27 +- 0.89 +- 1.56 +3.07 -2.10 mu b. Angular
distributions of the Sigma(1385)^+ in different reference frames are found to
be compatible with the hypothesis that 33 % of Sigma(1385)^+ result from the
decay of an intermediate Delta^{++} resonance.Comment: 12 pages; 12 figures; submitted to PR
- …