A 3-D Track-Finding Processor for the CMS Level-1 Muon Trigger

We report on the design and test results of a prototype processor for the CMS Level-1 trigger that performs 3-D track reconstruction and measurement from data recorded by the cathode strip chambers of the endcap muon system. The tracking algorithms are written in C++ using a class library we developed that facilitates automatic conversion to Verilog. The code is synthesized into firmware for field-programmable gate-arrays from the Xilinx Virtex-II series. A second-generation prototype has been developed and is currently under test. It performs regional track-finding in a 60 degree azimuthal sector and accepts 3 GB/s of input data synchronously with the 40 MHz beam crossing frequency. The latency of the track-finding algorithms is expected to be 250 ns, including geometrical alignment correction of incoming track segments and a final momentum assignment based on the muon trajectory in the non-uniform magnetic field in the CMS endcaps.Comment: 7 pages, 5 figures, proceedings for the conference on Computing in High Energy and Nuclear Physics, March 24-28 2003, La Jolla, Californi

A randomized controlled trial to compare aesthetic outcomes of immediately placed implants with and without immediate provisionalization

IntroductionThere are mixed results regarding the aesthetic advantage of immediate provisionalization of dental implants. Therefore, this study aimed to compare facial mucosal level of single immediately placed implants with and without immediate provisionalization.MethodsSingle implants were immediately placed to replace a hopeless maxillary anterior or premolar tooth in 40 subjects. Each implant was randomly assigned to receive a nonâ occluding temporary crown or a healing abutment after implant placement. At 4 months, these implants were permanently restored and followed up for 12 months. Clinical and radiographic parameters were measured and compared.ResultsThe implant survival rate at 12 months in the test and control group was 90% and 100%, respectively. Midâ facial mucosal marginal level and papilla height changes were minimal within groups, and no significant differences were found between the two groups. The amount of marginal bone remodelling was modest, with no significant difference between the two groups. Radiographic bone changes were not statistically different between the groups, except for the vertical crestal bone resorption.ConclusionImmediate implant placement with or without provisionalization can achieve stable vertical soft tissue level for 12 months as compared to preâ extraction level. However, immediate provisionalization was not able to improve the aesthetic outcome further.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151807/1/jcpe13171.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151807/2/jcpe13171_am.pd

The effects of matter density uncertainties on neutrino oscillations in the Earth

We compare three different methods to evaluate uncertainties in the Earth's matter density profile, which are relevant to long baseline experiments, such as neutrino factories.Comment: 3 pages, 1 figure. Talk given at the NuFact'02 Workshop, London, 1-6 July, 200

Search in weighted complex networks

We study trade-offs presented by local search algorithms in complex networks which are heterogeneous in edge weights and node degree. We show that search based on a network measure, local betweenness centrality (LBC), utilizes the heterogeneity of both node degrees and edge weights to perform the best in scale-free weighted networks. The search based on LBC is universal and performs well in a large class of complex networks.Comment: 14 pages, 5 figures, 4 tables, minor changes, added a referenc

Coexistence of antiferromagnetic order and unconventional superconductivity in heavy fermion compounds CeRh_{1-x}Ir_xIn_5: nuclear quadrupole resonance studies

We present a systematic ^{115}In NQR study on the heavy fermion compounds CeRh_{1-x}Ir_xIn_5 (x=0.25, 0.35, 0.45, 0.5, 0.55 and 0.75). The results provide strong evidence for the microscopic coexistence of antiferromagnetic (AF) order and superconductivity (SC) in the range of 0.35 \leq x \leq 0.55. Specifically, for x=0.5, T_N is observed at 3 K with a subsequent onset of superconductivity at T_c=0.9 K. T_c reaches a maximum (0.94 K) at x=0.45 where T_N is found to be the highest (4.0 K). Detailed analysis of the measured spectra indicate that the same electrons participate in both SC and AF order. The nuclear spin-lattice relaxation rate 1/T_1 shows a broad peak at T_N and follows a T^3 variation below T_c, the latter property indicating unconventional SC as in CeIrIn_5 (T_c=0.4 K). We further find that, in the coexistence region, the T^3 dependence of 1/T_1 is replaced by a T-linear variation below T\sim 0.4 K, with the value \frac{(T_1)_{T_c}}{(T_1)_{low-T}} increasing with decreasing x, likely due to low-lying magnetic excitations associated with the coexisting magnetism.Comment: 20 pages, 14 figure

Complex zeros of real ergodic eigenfunctions

We determine the limit distribution (as $\lambda \to \infty$) of complex zeros for holomorphic continuations \phi_{\lambda}^{\C} to Grauert tubes of real eigenfunctions of the Laplacian on a real analytic compact Riemannian manifold $(M, g)$ with ergodic geodesic flow. If $\{\phi_{j_k} \}$ is an ergodic sequence of eigenfunctions, we prove the weak limit formula \frac{1}{\lambda_j} [Z_{\phi_{j_k}^{\C}}] \to \frac{i}{\pi} \bar{\partial} {\partial} |\xi|_g, where [Z_{\phi_{j_k}^{\C}}] is the current of integration over the complex zeros and where $\bar{\partial}$ is with respect to the adapted complex structure of Lempert-Sz\"oke and Guillemin-Stenzel.Comment: Added some examples and references. Also added a new Corollary, and corrected some typo

Simultaneous Continuation of Infinitely Many Sinks Near a Quadratic Homoclinic Tangency

We prove that the $C^3$ diffeomorphisms on surfaces, exhibiting infinitely many sinksnear the generic unfolding of a quadratic homoclinic tangency of a dissipative saddle, can be perturbed along an infinite dimensional manifold of $C^3$ diffeomorphisms such that infinitely many sinks persist simultaneously. On the other hand, if they are perturbed along one-parameter families that unfold generically the quadratic tangencies, then at most a finite number of those sinks have continuation

The thermal equation of state of FeTiO_3 ilmenite based on in situ X-ray diffraction at high pressures and temperatures

We present in situ measurements of the unit-cell volume of a natural terrestrial ilmenite (Jagersfontein mine, South Africa) and a synthetic reduced ilmenite (FeTiO_3) at simultaneous high pressure and high temperature up to 16 GPa and 1273 K. Unit-cell volumes were determined using energy-dispersive synchrotron X-ray diffraction in a multi-anvil press. Mössbauer analyses show that the synthetic sample contained insignificant amounts of Fe^(3+) both before and after the experiment. Results were fit to Birch-Murnaghan thermal equations of state, which reproduce the experimental data to within 0.5 and 0.7 GPa for the synthetic and natural samples, respectively. At ambient conditions, the unit-cell volume of the natural sample [V_0 = 314.75 ± 0.23 (1 ) Å^3] is significantly smaller than that of the synthetic sample [V_0 = 319.12 ± 0.26 Å^3]. The difference can be attributed to the presence of impurities and Fe^(3+) in the natural sample. The 1 bar isothermal bulk moduli K_(T0) for the reduced ilmenite is slightly larger than for the natural ilmenite (181 ± 7 and 165 ± 6 GPa, respectively), with pressure derivatives K_0' = 3 ± 1. Our results, combined with literature data, suggest that the unit-cell volume of reduced ilmenite is significantly larger than that of oxidized ilmenite, whereas their thermoelastic parameters are similar. Our data provide more appropriate input parameters for thermo-chemical models of lunar interior evolution, in which reduced ilmenite plays a critical role