1,267 research outputs found
Acceleration Radiation for Orbiting Electrons
This paper presents an analysis of the radiation seen by an observer in
circular acceleration, for a magnetic spin. This is applied to an electron in a
storage ring, and the subtilty of the interaction of the spin with the spatial
motion of the electron is explicated. This interaction is shown to be time
dependent (in the radiating frame), which explains the strange results found
for the electron's residual polarisation in the literature. Finally, some brief
comments about the radiation emitted by an accelerating detector are made where
it is shown that the spectrum is correlated in that particles are emitted in
pairs.Comment: 21pp 7fi
Time and Amplitude of Afterpulse Measured with a Large Size Photomultiplier Tube
We have studied the afterpulse of a hemispherical photomultiplier tube for an
upcoming reactor neutrino experiment. The timing, the amplitude, and the rate
of the afterpulse for a 10 inch photomultiplier tube were measured with a 400
MHz FADC up to 16 \ms time window after the initial signal generated by an LED
light pulse. The time and amplitude correlation of the afterpulse shows several
distinctive groups. We describe the dependencies of the afterpulse on the
applied high voltage and the amplitude of the main light pulse. The present
data could shed light upon the general mechanism of the afterpulse.Comment: 11 figure
Effect of B-site Dopants on Magnetic and Transport Properties of LaSrCoRuO
Effect of Co, Ru and Cu substitution at B and B' sites on the magnetic and
transport properties of LaSrCoRuO have been investigated. All the doped
compositions crystallize in the monoclinic structure in the space group
indicating a double perovskite structure. While the magnetization and
conductivity increase in Co and Ru doped compounds, antiferromagnetism is seen
to strengthen in the Cu doped samples. These results are explained on the basis
of a competition between linear Co-O-Ru-O-Co and perpendicular Co-O-O-Co
antiferromagnetic interactions and due to formation of Ru-O-Ru ferromagnetic
networks
Neutron beam test of CsI crystal for dark matter search
We have studied the response of Tl-doped and Na-doped CsI crystals to nuclear
recoils and 's below 10 keV. The response of CsI crystals to nuclear
recoil was studied with mono-energetic neutrons produced by the
H(p,n)He reaction. This was compared to the response to Compton
electrons scattered by 662 keV -ray. Pulse shape discrimination between
the response to these 's and nuclear recoils was studied, and quality
factors were estimated. The quenching factors for nuclear recoils were derived
for both CsI(Na) and CsI(Tl) crystals.Comment: 21pages, 14figures, submitted to NIM
Quantum mechanics emerges from information theory applied to causal horizons
It is suggested that quantum mechanics is not fundamental but emerges from
classical information theory applied to causal horizons. The path integral
quantization and quantum randomness can be derived by considering information
loss of fields or particles crossing Rindler horizons for accelerating
observers. This implies that information is one of the fundamental roots of all
physical phenomena. The connection between this theory and Verlinde's entropic
gravity theory is also investigated.Comment: REvtex4-1, 6pages, 2 figures, final versio
Resolution Tests of CsI(Tl) Scintillators Read Out by Pin Diodes
This research was sponsored by the National Science Foundation Grant NSF PHY 87-1440
Effects of reducing dietary crude protein and metabolic energy in weaned piglets
The objective of this experiment was to determine the effects of a pure reduction in the dietary crude protein (CP) and metabolic energy (ME) contents on growth performance, nutrient digestibility, blood profile, faecal microflora and odour gas emission in weaned pigs. A total of 80 weaned piglets ((Landrace × Yorkshire) × Duroc) with a mean initial bodyweight (BW) of 6.8 ± 0.5 kg were randomly allotted to four treatments with four replicate pens of five piglets per pen (based on average BW) for 45 days. The dietary treatments consisted of i) CON: basal diet; ii) LME: reduction of 10% of ME in basal diet; iii) LCP: reduction of 10% of CP in basal diet; iv) MECP: reduction of 10% of CP and 10% of ME in basal diet. During the experimental period, average daily feed intake (ADFI) improved in piglets fed the LME and LCP diets, compared with those fed the CON diets. Average daily gain (ADG) and gain to feed (G : F) ratio decreased in piglets fed LCP, LME, and MECP diet, when compared with those fed the CON diet. However, during the total experimental period, ADG and G : F ratio were not affected by dietary treatment. With regard to nutrient digestibility, apparent total track digestibility (ATTD) of CP was not affected by experimental diets. The concentration of blood urea nitrogen (BUN) in blood decreased more in piglets fed LME, LCP, and MECP than those fed the CON diet. The emissions of ammonia (NH3), hydrogen sufide (H2S), and volatile fatty acids (VFAs) were lower in piglets fed LME, LCP, and MECP diet than those fed the CON diet. In conclusion, these results indicate that reduction in dietary CP and ME content did not decrease growth performance and nutrient digestibility, and they increased positive effects such as BUN and gas emission reduction.Keywords: Blood profile, digestibility, growth performance, odour emission, pi
Spatiotemporal Stochastic Resonance in Fully Frustrated Josephson Ladders
We consider a Josephson-junction ladder in an external magnetic field with
half flux quantum per plaquette. When driven by external currents, periodic in
time and staggered in space, such a fully frustrated system is found to display
spatiotemporal stochastic resonance under the influence of thermal noise. Such
resonance behavior is investigated both numerically and analytically, which
reveals significant effects of anisotropy and yields rich physics.Comment: 8 pages in two columns, 8 figures, to appear in Phys. Rev.
The GEMS Approach to Stationary Motions in the Spherically Symmetric Spacetimes
We generalize the work of Deser and Levin on the unified description of
Hawking radiation and Unruh effect to general stationary motions in spherically
symmetric black holes. We have also matched the chemical potential term of the
thermal spectrum of the two sides for uncharged black holes.Comment: Latex file, 12 pages, no figure; v2: typos fixed; v3: minor
corrections, final version published in JHE
Effects of various additives to enhance growth performance, blood profiles, and reduce malodour emissions in growing pigs
Experiment 1 was a feeding trial in which 75 (Landrace ⅹ Yorkshire) ⅹ Duroc pigs with average initial bodyweight (BW) of 26 ± 1 kg were used. It was assigned to three pigs/pen and five pens/treatment. Experiment 2 was a metabolic trial in which 25 (LandraceⅹYorkshire)ⅹDuroc pigs with average initial bodyweight (BW) of 36 ± 1 kg were used. The basal diet consisted of maize (57.71 %), soybean meal (32.45 %), and wheat bran (5 %). Treatments consisted of i) CON (control diet); ii) OE (organic acid + essential oils) (Aviplus-S®), that is, CON + 0.05 % OE; iii) OC (organic charcoal) (Olga Black®), that is, CON + 0.1 % OC; iv) AE (anise extracts) (RESQ®), that is, CON + 0.015 % AE; and v) PB (probiotics) (Bonvital®), that is, CON + 0.1 % PB. Average daily gain (ADG) and gain/feed ratio (G : F) were significantly higher in the OE and AE groups than in the others. Average daily feed intake (ADFI) for OE, OC, and AE treatments was significantly higher than that for CON and PB treatments. Dry matter (DM) digestibility was significantly higher in AE than CON. Crude protein (CP) was significantly higher in OE, AE, and PB than CON. CON and other treatments did not cause significant differences in blood l-density lipoprotein (LDL), and glucose. NH3 emissions were significantly lower in all treated groups than in CON. Among the treatments, NH3 emissions were lowest in OE and AE. H2S emissions were significantly lower in OE, AE, and PB than in CON. Among the treatments, OE and AE were most effective at reducing H2S emissions. The emissions of volatile fatty acids (VFAs) showed no significant difference between treatments and CON. In conclusion, this experiment was shown to be more effective on growth performance, malodour emission, blood profiles, and nutrient digestibility in OE and AE than other additives.Keywords: Digestibility, feed, influence, odour, supplementation, swin
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