9,364 research outputs found
KLOE results at the Frascati -factory DANE
The KLOE experiment at the Frascati -factory DANE has collected
about 0.5 fb of data till the end of the year 2002. These data allow to
perform a wide physics program, ranging from the physics of charged and neutral
kaons to radiative -decays. Results are presented for the lifetime
and the semileptonic processes . From the light meson
spectroscopy program, results on the decays as well as are presented.Comment: 5 pages, 3 figures, Proceedings contribution to the 10th Int.
Symposium on "Meson-Nucleon Physics and the Structure of the Nucleon"
(MENU04), Beijing, China, Aug. 30 - Sept. 4, 200
Viability of Penaeus monodon eggs after simulated transport conditions
P. monodon spawners, transported from maturation pens suffer from stress which in turn may lead to lowered spawning rate or fertility. Spawning the females in the maturation site and transporting the eggs to the hatchery site is being considered as an alternative. Egg transport costs may be reduced to a minimum by using eggs from ablated spawners, transported at high density with no aeration. Experiments on higher egg densities as well as on transport of nauplii should, however, be undertaken
ATLAS RPC Quality Assurance results at INFN Lecce
The main results of the quality assurance tests performed on the Resistive
Plate Chamber used by the ATLAS experiment at LHC as muon trigger chambers are
reported and discussed.
Since July 2004, about 270 RPC units has been certified at INFN Lecce site
and delivered to CERN, for being integrated in the final muon station of the
ATLAS barrel region.
We show the key RPC characteristics which qualify the performance of this
detector technology as muon trigger chamber in the harsh LHC enviroments.
These are dark current, chamber efficiency, noise rate, gas volume
tomography, and gas leakage.Comment: Comments: 6 pages, 1 table, 9 figures Proceedings of XXV Physics in
Collision-Prague, Czech Republic, 6-9 July 200
Eco-friendly gas mixtures for Resistive Plate Chambers based on Tetrafluoropropene and Helium
Due to the recent restrictions deriving from the application of the Kyoto
protocol, the main components of the gas mixtures presently used in the
Resistive Plate Chambers systems of the LHC experiments will be most probably
phased out of production in the coming years. Identifying possible replacements
with the adequate characteristics requires an intense R&D, which was recently
started, also in collaborations across the various experiments. Possible
candidates have been proposed and are thoroughly investigated. Some tests on
one of the most promising candidate - HFO-1234ze, an allotropic form of
tetrafluoropropane- have already been reported. Here an innovative approach,
based on the use of Helium, to solve the problems related to the too elevate
operating voltage of HFO-1234ze based gas mixtures, is discussed and the
relative first results are shown.Comment: 9 pages, 6 figures, 1 tabl
ATLAS RPC Cosmic Ray Teststand at INFN Lecce
We describe the design and functionality of the cosmic ray teststand built at
INFN Lecce for ATLAS RPC quality control assurance.Comment: XXIV Physics in Collisions Conference (PIC04), Boston, USA, June
2004, 3 pages, LaTex, 2 eps figures. MONP0
Growth characteristics of American Ginseng (Panax quinquefolius L.) woods and field - cultivated at Northern Europe
Received: February 19th, 2022 ; Accepted: May 15th, 2022 ; Published: May 16th, 2022 ; Correspondence: [email protected] Latvia, Northern Europe, American ginseng was grown in three forest types with
different dominant species, as well as in agricultural field conditions - cultivated under artificial
shade with three different types of mulches. Field cultivation yielded higher yields, root length,
and root weight than wood cultivation under dominant species Corylus avellana, Betula pendula,
and Picea abies. Mulching had a positive impact on ginseng growth in the field. Mulching with
straw and buckwheat hulls resulted in longer and heavier roots.
In American ginseng roots, the contents of six ginsenosides were determined: Rg1, Re, Rb1, Rc,
Rb2, and Rd. Re was the most abundant ginsenoside, followed by Rb1 > Rd > Rg1 = Rb2 > Rd.
The total content of ginsenosides in our study did not reach the 4 percent threshold set by US
Pharmacopeia.
These findings show that Panax quinquefolium can be grown in Northern Europe at 57°N, but it
takes more than four years to achieve adequate yields and ginsenoside content
Search for new phenomena in high-mass diphoton final states using 37 fb(-1) of proton-proton collisions collected at root(s) = 13 TeV with the ATLAS detector
Searches for new phenomena in high-mass diphoton final states with the
ATLAS experiment at the LHC are presented. The analysis is based on pp
collision data corresponding to an integrated luminosity of 36.7 fb(-1)
at a centre-of-mass energy root s = 13 TeV recorded in 2015 and 2016.
Searches are performed for resonances with spin 0, as predicted by
theories with an extended Higgs sector, and for resonances with spin 2,
using a warped extra-dimension model as a benchmark model, as well as
for non-resonant signals, assuming a large extra-dimension scenario. No
significant deviation from the Standard Model is observed. Upper limits
are placed on the production cross section times branching ratio to two
photons as a function of the resonance mass. In addition, lower limits
are set on the ultraviolet cutoff scale in the large extra-dimensions
model. (C) 2017 The Author(s). Published by Elsevier B.V
Search for new phenomena in dijet events using 37 fb(-1) of pp collision data collected at root s=13 TeV with the ATLAS detector
Dijet events are studied in the proton-proton collision dataset recorded
at root s = 13 TeV with the ATLAS detector at the Large Hadron Collider
in 2015 and 2016, corresponding to integrated luminosities of 3.5 fb(-1)
and 33.5 fb(-1) respectively. Invariant mass and angular distributions
are compared to background predictions and no significant deviation is
observed. For resonance searches, a new method for fitting the
background component of the invariant mass distribution is employed. The
dataset is then used to set upper limits at a 95\% confidence level on a
range of new physics scenarios. Excited quarks with masses below 6.0 TeV
are excluded, and limits are set on quantum black holes, heavy W'
bosons, W* bosons, and a range of masses and couplings in a Z' dark
matter mediator model. Model-independent limits on signals with a
Gaussian shape are also set, using a new approach allowing factorization
of physics and detector effects. From the angular distributions, a scale
of new physics in contact interaction models is excluded for scenarios
with either constructive or destructive interference. These results
represent a substantial improvement over those obtained previously with
lower integrated luminosity
Measurement of jet activity produced in top-quark events with an electron, a muon and two b-tagged jets in the final state in pp collisions root s=13TeV with the ATLAS detector
Measurements of jet activity in top-quark pair events produced in
proton-proton collisions are presented, using 3.2 fb of pp collision
data at a centre-of-mass energy of 13 TeV collected by the ATLAS
experiment at the Large Hadron Collider. Events are chosen by requiring
an opposite-charge pair and two b-tagged jets in the final state. The
normalised differential cross-sections of top-quark pair production are
presented as functions of additional-jet multiplicity and transverse
momentum, . The fraction of signal events that do not contain additional
jet activity in a given rapidity region, the gap fraction, is measured
as a function of the threshold for additional jets, and is also
presented for different invariant mass regions of the system. All
measurements are corrected for detector effects and presented as
particle-level distributions compared to predictions with different
theoretical approaches for QCD radiation. While the kinematics of the
jets from top-quark decays are described well, the generators show
differing levels of agreement with the measurements of observables that
depend on the production of additional jets
Reconstruction of primary vertices at the ATLAS experiment in Run 1 proton-proton collisions at the LHC
This paper presents the method and performance of primary vertex
reconstruction in proton-proton collision data recorded by the ATLAS
experiment during Run 1 of the LHC. The studies presented focus on data
taken during 2012 at a centre-of-mass energy of root s = 8 TeV. The
performance has been measured as a function of the number of
interactions per bunch crossing over a wide range, from one to seventy.
The measurement of the position and size of the luminous region and its
use as a constraint to improve the primary vertex resolution are
discussed. A longitudinal vertex position resolution of about 30 mu m is
achieved for events with high multiplicity of reconstructed tracks. The
transverse position resolution is better than 20 mu m and is dominated
by the precision on the size of the luminous region. An analytical model
is proposed to describe the primary vertex reconstruction efficiency as
a function of the number of interactions per bunch crossing and of the
longitudinal size of the luminous region. Agreement between the data and
the predictions of this model is better than 3\% up to seventy
interactions per bunch crossing
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