45,388 research outputs found
Evidence for the decay B0→J/ψω and measurement of the relative branching fractions of meson decays to J/ψη and J/ψη′
No full textFirst evidence of the B 0 → J / ψ ω decay is found and the B s 0 → J / ψ η and B s 0 → J / ψ η ′ decays are studied using a dataset corresponding to an integrated luminosity of 1.0 fb -1 collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV. The branching fractions of these decays are measured relative to that of the B 0 → J / ψ ρ 0 decay:frac(B (B 0 → J / ψ ω), B (B 0 → J / ψ ρ 0)) = 0.89 ± 0.19 (stat) - 0.13 + 0.07 (syst),frac(B (B s 0 → J / ψ η), B (B 0 → J / ψ ρ 0)) = 14.0 ± 1.2 (stat) - 1.5 + 1.1 (syst) - 1.0 + 1.1 (frac(f d, f s)),frac(B (B s 0 → J / ψ η ′), B (B 0 → J / ψ ρ 0)) = 12.7 ± 1.1 (stat) - 1.3 + 0.5 (syst) - 0.9 + 1.0 (frac(f d, f s)), where the last uncertainty is due to the knowledge of f d / f s, the ratio of b-quark hadronization factors that accounts for the different production rate of B 0 and B s 0 mesons. The ratio of the branching fractions of B s 0 → J / ψ η ′ and B s 0 → J / ψ η decays is measured to befrac(B (B s 0 → J / ψ η ′), B (B s 0 → J / ψ η)) = 0.90 ± 0.09 (stat) - 0.02 + 0.06 (syst)
Observations of Bºs→ψ(2S)η and Bº(s)→ψ(2S)π+π- decays
No full textFirst observations of the B0s
→ψ(2S)η, B0 →ψ(2S)π
+
π
− and B0s
→ψ(2S)π
+
π
− decays are made
using a dataset corresponding to an integrated luminosity of 1.0 fb−1 collected by the LHCb experiment in
proton–proton collisions at a centre-of-mass energy of
√
s = 7 TeV. The ratios of the branching fractions
of each of the ψ(2S) modes with respect to the corresponding J/ψ decays are
B(B0s
→ψ(2S)η)
÷
B(B0s
→J/ψη)
= 0.83± 0.14 (stat)±0.12 (syst) ±0.02 (B),
;
B(B0→ψ(2S)π
+
π
−
)
÷
B(B0→J/ψπ
+
π
−
)
= 0.56± 0.07 (stat)±0.05 (syst)± 0.01 (B),
;
B(B0s
→ψ(2S)π
+
π
−
)
÷
B(B0s
→J/ψπ
+
π
−
)
= 0.34± 0.04 (stat)±0.03 (syst)± 0.01 (B),
where the third uncertainty corresponds to the uncertainties of the dilepton branching fractions of the J/ψ
and ψ(2S) meson decays
Measurement of the branching fraction
No full textThe B
0
s
→ J/ψK
0
S
branching fraction is measured in a data sample corresponding to 0.41 fb−1
of integrated luminosity collected with the LHCb detector at the LHC. This channel is sensitive to
the penguin contributions affecting the sin 2β measurement from B
0
→ J/ψK
0
S
. The time-integrated
branching fraction is measured to be B(B
0
s
→ J/ψK
0
S
) = (1.83±0.28)×10−5
. This is the most precise
measurement to date
Measurement of the B0–B0 oscillation frequency Δmd with the decays B0→D−π+ and B0→ J/ψK∗0
No full textThe B
0
–B
0
oscillation frequency Δmd is measured by the LHCb experiment using a dataset corresponding
to an integrated luminosity of 1.0 fb−1
of proton–proton collisions at √
s = 7 TeV, and is found to be
Δmd
=0.5156±0.0051 (stat.)±0.0033 (syst.) ps−1
. The measurement is based on results from analyses
of the decays B
0
→ D
−π
+ (D
−
→ K
+π
−π
−) and B
0
→ J/ψK
∗0
(J/ψ →μ
+μ
−,K
∗0
→ K
+π
−) and
their charge conjugated modes
Measurement of the time-dependent CP asymmetry in B0 -> J/ψ KS0 decays
No full textThis Letter reports a measurement of the CP violation observables SJ/ψK0S and CJ/ψK0S in the decay channel B0→J/ψK0S performed with 1.0 fb−1 of pp collisions at s√=7 TeV collected by the LHCb experiment. The fit to the data yields SJ/ψK0S=0.73±0.07(stat)±0.04(syst) and CJ/ψK0S=0.03±0.09(stat)±0.01(syst). Both values are consistent with the current world averages and within
expectations from the Standard Model
Letter from Arno B. Cammerer to J. R. Eakin
No full textLetter from Arno B. Cammerer to J. R. Eakin describing the procedure for purchasing Bright Angel Trail
Letter from Carl Hayden to J. B. Rickel
No full textLetter from Carl T. Hayden to J. B. Rickel concerning proposed changes to Grand Canyon National Park boundaries
Efeito da desmama antecipada e suplementação alimentar no desempenho reprodutivo de vacas e novilhas criadas em pastagens nativas no Pantanal.
No full textRESUMO - O objetivo deste trabalho foi avaliar o efeito da desmama antecipada na taxa de natalidade de vacas multíparas e primíparas, e o uso da suplementação no desenvolvimento e idade ao primeiro parto de novilhas nulíparas, em pastagem nativa. O trabalho foi realizado na sub-região da Nhecolândia, MS, entre agosto/1997 e junho/2000. Na primeira fase (agosto/1997 a outubro/1998), avaliou-se o efeito da desmama antecipada na taxa de natalidade de vacas multíparas e primíparas. Dois grupos homogêneos de matrizes tiveram: (A) bezerros desmamados com cinco meses de idade e suplementados com ração liquida e (B) bezerros desmamados com oito meses de idade. A desmama antecipada resultou em taxa de natalidade superior ( P< 0,001) para o grupo A (81,5%) do que para o grupo B (13,1%). Na segunda fase (outubro/1998 a junho/2000), avaliou-se o efeito da suplementação no ganho de peso e idade à primeira cria das novilhas oriundas dos grupos A e B. Independente do grupo de origem (A ou B), as novilhas em recria apresentaram um ganho de peso médio diário de 0,290 g durante o período de suplementação, alcançando peso vivo de 270 kg na segunda estação chuvosa. Esse fato resultou em uma antecipação ao crescimento normal de, aproximadamente, um ano, embora com pouco efeito no índice de prenhez. Resultados indicam que a baixa taxa de natalidade na região do Pantanal deve-se à restrição alimentar das vacas durante o período de lactação. ABSTRACT - The objective of this study was to evaluate the effect of early weaning on pregnancy rate and the use of supplement on development and age at first calving at replacement heifers grazing native pasture. The experiment was conducted at the subregion of Nhecolândia, starting from 08.97 and ending at 06.2000. The effect of early weaning on pregnancy rate at cows and heifers was evaluated at the first experimental period (08.97 to 10.98). Two homogeneous groups of cows had: (A) calves weaned at five months of age, and supplemented with liquid ration and (B) calves weaned at 8 months of age. Early weaning increased (P<0,001) calving rate for group A cows (81,5%) compared to group B cows (13,1%). For the second period (10.98 to 06.2000) it was evaluated the effect of supplementation on weight gain and age calving of heifers born from groups A and B cows and heifers. Apart from birth of group A or B cows, average gain of heifers during supplementation was 0,290 g per day, attained on average liveweight of 270 kg at the second rainy season. This fact means antecipation target weight for mating of about one year, although with no effect on pregnancy rate. Results from this experiment indicate that the main cause of low calving rates at the Pantanal region is due to the restriction of feed after calving.Título em inglês: Effect on antecipated weaning and of supplementary feeding on reprodutive performance of cows and haifers raised on native grasslands in the Brazilian Pantanal wetland
Measurement of b-hadron masses
No full textMeasurements of b-hadron masses are performed with the exclusive decay modes B +→J/ψK +, B 0→J/ψK +, B0→J/ψKS0, Bs0→J/ψφ and Λb0→J/ψΛ using an integrated luminosity of 35pb -1 collected in pp collisions at a centre-of-mass energy of 7 TeV by the LHCb experiment. The momentum scale is calibrated with J/ψ→μ +μ - decays and verified to be known to a relative precision of 2 ×10 -4 using other two-body decays. The results are more precise than previous measurements, particularly in the case of the Bs0 and Λb0 masses
Ganho de peso e parasitismo em novilhas tratadas com produtos homeopáticos, fitoterápicos e alopáticos: ano I.
No full textForam avaliados cinco tratamentos: A- Controle, B- Fator C&MC®, C- Parasitário Real H®, D- Bioneen® e E- Alopático.PH 052
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