10 research outputs found
Study of the production of and hadrons in collisions and first measurement of the branching fraction
The product of the () differential production
cross-section and the branching fraction of the decay () is
measured as a function of the beauty hadron transverse momentum, ,
and rapidity, . The kinematic region of the measurements is and . The measurements use a data sample
corresponding to an integrated luminosity of collected by the
LHCb detector in collisions at centre-of-mass energies in 2011 and in 2012. Based on previous LHCb
results of the fragmentation fraction ratio, , the
branching fraction of the decay is
measured to be \begin{equation*} \mathcal{B}(\Lambda_b^0\rightarrow J/\psi
pK^-)= (3.17\pm0.04\pm0.07\pm0.34^{+0.45}_{-0.28})\times10^{-4},
\end{equation*} where the first uncertainty is statistical, the second is
systematic, the third is due to the uncertainty on the branching fraction of
the decay , and the
fourth is due to the knowledge of . The sum of the
asymmetries in the production and decay between and
is also measured as a function of and .
The previously published branching fraction of , relative to that of , is updated.
The branching fractions of are determined.Comment: 29 pages, 19figures. All figures and tables, along with any
supplementary material and additional information, are available at
https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-032.htm
Measurements of long-range near-side angular correlations in TeV proton-lead collisions in the forward region
Two-particle angular correlations are studied in proton-lead collisions at a
nucleon-nucleon centre-of-mass energy of TeV, collected
with the LHCb detector at the LHC. The analysis is based on data recorded in
two beam configurations, in which either the direction of the proton or that of
the lead ion is analysed. The correlations are measured in the laboratory
system as a function of relative pseudorapidity, , and relative
azimuthal angle, , for events in different classes of event
activity and for different bins of particle transverse momentum. In
high-activity events a long-range correlation on the near side, , is observed in the pseudorapidity range . This
measurement of long-range correlations on the near side in proton-lead
collisions extends previous observations into the forward region up to
. The correlation increases with growing event activity and is found
to be more pronounced in the direction of the lead beam. However, the
correlation in the direction of the lead and proton beams are found to be
compatible when comparing events with similar absolute activity in the
direction analysed.Comment: All figures and tables, along with any supplementary material and
additional information, are available at
https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-040.htm
Evidence for the strangeness-changing weak decay
Using a collision data sample corresponding to an integrated luminosity
of 3.0~fb, collected by the LHCb detector, we present the first search
for the strangeness-changing weak decay . No
hadron decay of this type has been seen before. A signal for this decay,
corresponding to a significance of 3.2 standard deviations, is reported. The
relative rate is measured to be
, where and
are the and fragmentation
fractions, and is the branching
fraction. Assuming is bounded between 0.1 and
0.3, the branching fraction would lie
in the range from to .Comment: 7 pages, 2 figures, All figures and tables, along with any
supplementary material and additional information, are available at
https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-047.htm
Model-independent measurement of mixing parameters in Dââ K ÏÏ decays
The first model-independent measurement of the charm mixing parameters in the
decay is reported, using a sample of collision
data recorded by the LHCb experiment, corresponding to an integrated luminosity
of 1.0 fb at a centre-of-mass energy of 7 TeV. The measured values are
\begin{eqnarray*} x &=& (-0.86 \pm 0.53 \pm 0.17) \times 10^{-2}, \\ y &=&
(+0.03 \pm 0.46 \pm 0.13) \times 10^{-2}, \end{eqnarray*} where the first
uncertainties are statistical and include small contributions due to the
external input for the strong phase measured by the CLEO collaboration, and the
second uncertainties are systematic.Comment: 25 pages, 3 figures. Sign error in x fixed as of v2. All figures and
tables, along with any supplementary material and additional information, are
available at
https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-042.htm
A precise measurement of the meson oscillation frequency
The oscillation frequency, , of mesons is measured using
semileptonic decays with a or meson in the final state, in a
data sample of collisions collected by the LHCb detector corresponding to
an integrated luminosity of 3.0\mbox{fb}^{-1}. A combination of the two decay
modes gives , where the
first uncertainty is statistical and the second is systematic. This is the most
precise single measurement of this parameter. It is compatible with the current
world average and has similar precision.Comment: All figures and tables, along with any supplementary material and
additional information, are available at
https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-031.htm
Dissociative recombination and excitation of H2O+ and HDO+
Dissociative recombination and excitation of H2O+ and HDO+ in the vibrational ground state have been studied at the heavy-ion storage ring ASTRID. Absolute cross sections have been measured in the energy range from similar to 0.1 meV to similar to 50 eV. The total cross sections for dissociative recombination are essentially the same for the two molecular ions. Complete branching ratios for all possible product channels in dissociative recombination at E = 0 have been determined. Three-particle breakup accounts for similar to 60% of the recombination events. With HDO+,recombination into OD + H is twice as probable as recombination into OH+D. An isotope effect is also evident in the cross sections for dissociative excitation of HDO+, where H+ production is more likely than D+ production. [S1050-2947(99)01910-1]
Rekruttering til kirkelige stillinger. En undersÞkelse blant studenter pÄ studier som kvalifiserer til jobb som prest, kateket, diakon eller kirkemusiker
Rekruttering til alle kirkelige stillinger (prest, diakon, kirkemusiker, kateket og andre undervisningsstillinger er i dag en stor utfordring i Den norske kirke (Dnk). Prognoser viser at det er for fÄ som utdanner seg til kirkelig tjeneste i forhold til behovene. Det er satt i gang flere tiltak med tanke pÄ rekruttering til Dnk, men det er gjort lite forskning pÄ feltet
Observation of and decays and a measurement of the baryon mass
20 pages, 4 figures. All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-060.htmlInternational audienceThe decays and are observed in a data sample corresponding to an integrated luminosity of 3fb, collected in proton-proton collisions at 7 and 8TeV centre-of-mass energies by the LHCb detector. The mesons are reconstructed through the decay modes and . The branching fractions relative to that of are measured to be \begin{eqnarray*} \frac{\mathcal{B}(\Lambda_b^0 \to \psi(2S) pK^-)} {\mathcal{B}(\Lambda_b^0 \to J/\psi pK^-)} & = & (20.70\pm 0.76\pm 0.46\pm 0.37)\times10^{-2} \,, \frac{\mathcal{B}(\Lambda_b^0 \to J/\psi \pi^+ \pi^- pK^-)} {\mathcal{B}(\Lambda_b^0 \to J/\psi pK^-)} & = & (20.86\pm 0.96\pm 1.34)\times10^{-2} \,, \end{eqnarray*} where the first uncertainties are statistical, the second are systematic and the third is related to the knowledge of and branching fractions. The mass of the baryon is measured to be where the uncertainties are statistical and systematic
High standard detached house
The bachelorâs thesis is handeling project documentation of high standard detached house. House is two-storey high. It is suited for four to six-member family. Detached house is rectangular shaped with two fitting rectangulars and it is roofed by flat roof. The roof above garage and kitchen with dining room is designed like terrace. It is open from second floor
Wohnsituation Alleinerziehender Materialien zu einem Forschungsfeld des Experimentellen Wohnungs- und Staedtebaus 'Wohnsituation Alleinerziehender und alleinstehender Schwangerer in Notlage'
UuStB Koeln(38)-930106270 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman