76,163 research outputs found
Letter from Thos. J. Henley to Charles E. Mix with letters from V. E. Geiger and S. Hastings, 1858
No full textEnclosed a report of Agent V. E. Geiger relative to the farming operation at Nome Lackee Reserve. Also included a report from Dr. S. Hastings for the 1st Quarter of 1858
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)
Solutions to the radiative transfer equation with GPU-accelerated Monte Carlo simulations : applied to applications such as surface recognition and determination of the optical properties of scattering media
No full textThis thesis presents the results of six research articles that use Monte Carlo simulations to model light propagation in scattering media for various applications.
In "Determination of the optical properties of three-layered turbid media in the time domain using the P₃ approximation" (S. Geiger, D. Reitzle, A. Liemert, and A. Kienle, 2019), the inverse problem of time-resolved solutions to the radiative transfer equation is investigated. Monte Carlo simulations serve as a reference for the spherical harmonics approximation. The study finds that the P₃ approximation offers a significant advantage over the diffusion approximation.
"Semianalytical solution for the transient temperature in a scattering and absorbing slab consisting of three layers heated by a light source" (D. Reitzle, S. Geiger, A. Liemert, and A. Kienle, 2021) presents and validates a semi-analytical solution for the time-dependent heat distribution in a three-layered, laterally infinite scattering and absorbing slab illuminated by an obliquely incident, collimated beam of light.
In "Solutions for single-scattered radiance in the semi-infinite medium based on radiative transport theory" (A. Liemert, S. Geiger, and A. Kienle, 2021), solutions for the single-scattered radiance in the semi-infinite medium are presented and validated against Monte Carlo simulations, showing perfect agreement.
The article "Single scattering models for radiative transfer of isotropic and cone-shaped light sources in fog" (S. Geiger, A. Liemert, D. Reitzle, M. Bijelic, A. Ramazzina, W. Ritter, F. Heide, and A. Kienle, 2023) presents improvements to the single scattering solution of the radiative transfer equation in indefinitely spaced scattering fog. Both isotropic and cone-shaped light sources are investigated. The analytical solutions demonstrate perfect agreement with the Monte Carlo simulations. The scattering phase function for both the analytical solutions and the Monte Carlo simulations accounts for the particle distribution of the fog droplets. In the examples considered, the single scattering solution serves as a very good approximation compared to the solution that includes all scattering events.
Improvements to topography reconstruction of volume scattering objects using structured light are detailed in "Improved topography reconstruction of volume scattering objects using structured light" (S. Geiger, P. Hank, and A. Kienle, 2022). We simulate light propagation inside the object and use this information to correct the phase of the structured light, taking into account the projection and detection directions. This leads to a significant improvement in the reconstructed geometry.
In "Improved topographic reconstruction of turbid media in the spatial frequency domain including the determination of the reduced scattering and absorption coefficients" (S. Geiger, P. Hank, and A. Kienle, 2023), we improve the approach to reconstruct unknown optical properties and correct the surface geometry in a single step.
In addition to these articles, we provide an introduction that motivates the use of the radiative transfer equation and GPU-accelerated Monte Carlo simulations for the applications presented
Measurement of the CP-violating phase \phi s in Bs->J/\psi\pi+\pi- decays
No full textMeasurement of the mixing-induced CP-violating phase phi_s in Bs decays is of prime importance in probing new physics. Here 7421 +/- 105 signal events from the dominantly CP-odd final state J/\psi pi+ pi- are selected in 1/fb of pp collision data collected at sqrt{s} = 7 TeV with the LHCb detector. A time-dependent fit to the data yields a value of phi_s=-0.019^{+0.173+0.004}_{-0.174-0.003} rad, consistent with the Standard Model expectation. No evidence of direct CP violation is found
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 ratio of prompt χ c to J / ψ production in pp collisions at √s = 7 TeV
No full textThe prompt production of charmonium χ c and J / ψ states is studied in proton-proton collisions at a centre-of-mass energy of √s = 7 TeV at the Large Hadron Collider. The χ c and J / ψ mesons are identified through their decays χ c → J / ψ γ and J / ψ → μ + μ - using 36 pb - 1 of data collected by the LHCb detector in 2010. The ratio of the prompt production cross-sections for χ c and J / ψ, σ (χ c → J / ψ γ) / σ (J / ψ), is determined as a function of the J / ψ transverse momentum in the range 2 < p T J / ψ < 15 GeV / c. The results are in excellent agreement with next-to-leading order non-relativistic expectations and show a significant discrepancy compared with the colour singlet model prediction at leading order, especially in the low p T J / ψ region
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 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
Special Issue - Six articles on immigration policy.
No full textThe Romanian Journal of European Studies No.4/2005 ISSN 1583 - 199X. EUV - Editura Universitatii de Vest, Timisoara, 2005 The British Coucil in Bucharest and The School of High Comparative European Studies (SISEC), within the West University of Timisoara, edited The Romanian Journal of European Studies No.4/2005 - special issue on migration and mobility (Guest editor: Mr. Martin GEIGER, Bonn University, Germany; contact: [email protected]). CONTENTS: Foreword; Grigore Silasi ... page 5 Editorial; Martin Geiger ... pages 7 - 8 Forms and Features of the Post-Enlargement Migration Space; Paolo Ruspini ... pages 9 - 18 Managing Migration for an Enlarging Europe - Inter-governmental Organizations and the Governance of the Migration Flows; Martin Geiger ... pages 19 - 30 Balkan Migrations and The European Union: Patterns and Trends; Martin Baldwin-Edwards ... pages 31 - 43 Workers' Mobility': Europe's Integration and Second Thoughts; Peter van Krieken ... pages 45 - 53 Romania's External Migration in the Context of Accesion to the EU: Mechanisms, Institutions and Social-Cultural Issues; Luminita Nicolescu, Daniela-Luminita Constantin ... pages 55 - 63 Migrations et incidence sur la répartition spatiale de la population en Roumanie au niveau national et régional; Vasile Ghetau ... pages 65 - 8
Author Correction: Establishment and equilibrium levels of deleterious mutations in large populations (Scientific Reports, (2019), 9, 1, (10384), 10.1038/s41598-019-46803-7)
No full textThe original version of this Article contained errors. Affiliations 1 and 2 were reversed. Secondly, Affiliation 7 was incorrectly given as ‘Institute for Cellular and Molecular Medicine, Department of Immunology, and SAMRC Extramural Unit for Stem Cell Research and Therapy, Faculty of Health Sciences, University of Pretoria, Pretoria, 0084, South Africa’. Thirdly, an affiliation was omitted for the author Michael S. Pepper, which is now listed as Affiliation 8. Fourthly, Affiliation 1 was omitted for the author Johan W. Viljoen. Finally, Augustinus J. van Zyl was incorrectly affiliated with ‘Institute for Maternal and Child Health, IRCCS ‘Burlo Garofolo’, Trieste, Italy.’ The correct author affiliations are listed below: Affiliation 1: Department of Electrical, Electronic and Computer Engineering, EBIT, University of Pretoria, Pretoria 0028, South Africa Johan W. Viljoen and J. Pieter de Villiers Affiliation 2: Development, Research and Technology Department, Hensoldt Optronics, Centu..
- …
