4,714 research outputs found
A luminosity monitor for the A4 parity violation experiment at MAMI
A water Cherenkov luminosity monitor system with associated electronics has
been developed for the A4 parity violation experiment at MAMI. The detector
system measures the luminosity of the hydrogen target hit by the MAMI electron
beam and monitors the stability of the liquid hydrogen target. Both is required
for the precise study of the count rate asymmetries in the scattering of
longitudinally polarized electrons on unpolarized protons. Any helicity
correlated fluctuation of the target density leads to false asymmetries. The
performance of the luminosity monitor, investigated in about 2000 hours with
electron beam, and the results of its application in the A4 experiment are
presented.Comment: 22 pages, 12 figures, submitted to NIM
Faktor-faktor yang Mempengaruhi Perilaku Ibu Nifas dalam Mengkonsumsi Tuo Nifarö di Kecamatan Lotu Kabupaten Nias Utara
Tuo nifarö istypicalofNiasdrink that contains alcohol that resulted from distillation of cocoa. Tuo nifarö can be utilizedfor many purposes, one of them usedfor post-partum period treatment. The aim of this research is to knowing the determinant of post-partum mother's behavior who consumedtuonfaroin Lotu, District of North Nias. This kind of researchis descriptivequantitative andqualitative approachto completethe required datawith a sample of 52 people. The resultsof research onthe characteristics ofrespondents,59.6% were25-35years and61.5% of respondentshavea loweducation level. 61.5% of post-partummothers have the moderate trust levelson benefit ofconsumingtuo nifarö. In terms ofnormativebelief, theconsumptionof alcoholic beveragessuch astuo nifarö for post-partum mothers is affected bythe role offamiliesand communitiesthatinfluence the post-partum mothersto act. Attitudetowardconsumption of tuo nifarö 53.8% wereatmoderatelevels. In terms ofaction, 55.8% of respondentsconsumealcoholic beveragespostpartum, where82.8% had a loweducational level, 48.3% have the confidenceandgood judgment, and 58.6% at a moderate level, 100% supportedbyfamiliesand89.7% are supportedby the community. 72.4% of respondentshadconsumedblack beer as a substitutefor various reasons. This occasion should be maintained with regard to alcohol content, and health workers need to explore the benefits of taking tuo nifar
Daily cycle in oxygen consumption by the sea anemone Nematostella vectensis Stephenson
© The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Biology Open (2016): 1-4, doi:10.1242/bio.013474.In bilaterian animals, the circadian clock is intimately involved in regulating energetic metabolism. Although cnidarians exhibit diel behavioral rhythms including cycles in locomotor activity, tentacle extension and spawning, daily cycles in cnidarian metabolism have not been described. To explore a possible circadian metabolic cycle, we maintained the anemone Nematostella vectensis in a 12 h light/dark cycle, a reversed light cycle, or in constant darkness. Oxygen consumption rates were measured at intervals using an optical oxygen meter. Respiration rates responded to entrainment with higher rates during light periods. During a second experiment with higher temporal resolution, respiration rates peaked late in the light period. The diel pattern could be detected after six days in constant darkness. Together, our results suggest that respiration rates in Nematostella exhibit a daily cycle that may be under circadian control and that the cycle in respiration rate is not driven by the previously described nocturnal increase in locomotor activity in this species.Funding was provided by the US–Israel Binational Science Foundation [Grant 201187]. I.T.J. was supported by the WHOI Summer Student Fellow program, which is partially funded by the National Science Foundation Research Experience for Undergraduates program. A.M.R. was supported by National Institutes of Heath [R15GM114740]
Reconstruction methods — P‾ANDA focussing-light guide disc DIRC
The Focussing-Lightguide Disc DIRC will provide crucial Particle Identification (PID) information for the P‾ANDA experiment at FAIR, GSI. This detector presents a challenging environment for reconstruction due to the complexity of the expected hit patterns and the operating conditions of the P‾ANDA experiment. A discussion of possible methods to reconstruct PID from this detector is given here. Reconstruction software is currently under development
Measurement of the Transverse Beam Spin Asymmetry in Elastic Electron Proton Scattering and the Inelastic Contribution to the Imaginary Part of the Two-Photon Exchange Amplitude
We report on a measurement of the asymmetry in the scattering of transversely
polarized electrons off unpolarized protons, A, at two Q values of
\qsquaredaveragedlow (GeV/c) and \qsquaredaveragedhighII (GeV/c) and a
scattering angle of . The measured transverse
asymmetries are A(Q = \qsquaredaveragedlow (GeV/c)) =
(\experimentalasymmetry alulowcorr \statisticalerrorlow
\combinedsyspolerrorlowalucor) 10 and
A(Q = \qsquaredaveragedhighII (GeV/c)) = (\experimentalasymme
tryaluhighcorr \statisticalerrorhigh
\combinedsyspolerrorhighalucor) 10. The first
errors denotes the statistical error and the second the systematic
uncertainties. A arises from the imaginary part of the two-photon
exchange amplitude and is zero in the one-photon exchange approximation. From
comparison with theoretical estimates of A we conclude that
N-intermediate states give a substantial contribution to the imaginary
part of the two-photon amplitude. The contribution from the ground state proton
to the imaginary part of the two-photon exchange can be neglected. There is no
obvious reason why this should be different for the real part of the two-photon
amplitude, which enters into the radiative corrections for the Rosenbluth
separation measurements of the electric form factor of the proton.Comment: 4 figures, submitted to PRL on Oct.
Measurement of Strange Quark Contributions to the Nucleon's Form Factors at Q^2=0.230 (GeV/c)^2
We report on a measurement of the parity-violating asymmetry in the
scattering of longitudinally polarized electrons on unpolarized protons at a
of 0.230 (GeV/c)^2 and a scattering angle of \theta_e = 30^o - 40^o.
Using a large acceptance fast PbF_2 calorimeter with a solid angle of
\Delta\Omega = 0.62 sr the A4 experiment is the first parity violation
experiment to count individual scattering events. The measured asymmetry is
A_{phys} =(-5.44 +- 0.54_{stat} +- 0.27_{\rm sys}) 10^{-6}. The Standard Model
expectation assuming no strangeness contributions to the vector form factors is
. The difference is a direct measurement of the
strangeness contribution to the vector form factors of the proton. The
extracted value is G^s_E + 0.225 G^s_M = 0.039 +- 0.034 or F^s_1 + 0.130 F^s_2
= 0.032 +- 0.028.Comment: 5 pages, 3 figures, submitted to Phys. Rev. Letters on Dec 11, 200
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