Search results for "Signal processing"
showing 10 items of 2451 documents
Top quark mass measurement in the lepton plus jets channel using a modified matrix element method
2008
We report a measurement of the top quark mass, m(t), obtained from p(p)over bar collisions at root s=1.96 TeV at the Fermilab Tevatron using the CDF II detector. We analyze a sample corresponding to an integrated luminosity of 1.9 fb(-1). We select events with an electron or muon, large missing transverse energy, and exactly four high-energy jets in the central region of the detector, at least one of which is tagged as coming from a b quark. We calculate a signal likelihood using a matrix element integration method, where the matrix element is modified by using effective propagators to take into account assumptions on event kinematics. Our event likelihood is a function of m(t) and a parame…
COMPASS—A COMPAct decay spectroscopy set-up
2018
Abstract A compact silicon detector array with high spatial granularity and fast, fully digital data recording has been developed and commissioned for the investigation of heavy and superheavy nuclear species. The detector array can be combined in close geometry with large volume germanium detectors. It offers comprehensive particle and photon coincidence and correlation spectroscopy by highly efficient evaporation residue, α , γ , conversion electron and X-ray detection supported by the high granularity of the implantation chip. Access to fast decay events in the sub-microsecond region is made possible by the fast timing properties of the digital signal processing. A novel Si-chip support …
Event Excess in the MiniBooNE Search forν¯μ→ν¯eOscillations
2010
The MiniBooNE experiment at Fermilab reports results from a search for {nu}{sub {mu}{yields}{nu}e} oscillations, using a data sample corresponding to 5.66x10{sup 20} protons on target. An excess of 20.9{+-}14.0 events is observed in the energy range 475<E{sub {nu}}{sup QE}<1250 MeV, which, when constrained by the observed {nu}{sub {mu}} events, has a probability for consistency with the background-only hypothesis of 0.5%. On the other hand, fitting for {nu}{sub {mu}{yields}{nu}e} oscillations, the best-fit point has a {chi}{sup 2} probability of 8.7%. The data are consistent with {nu}{sub {mu}{yields}{nu}e} oscillations in the 0.1 to 1.0 eV{sup 2} {Delta}m{sup 2} range and with the evidence…
Design, construction and performance of the energy compressing system of the Mainz 300 MeV electron linac
1973
Abstract For the sake of better energy resolution of the 300 MeV electron linac of Mainz university a system has been built which transforms a sharply bunched beam of poor energy resolution into a beam of sharply defined energy, while its bunches are smeared out. The system is described, its design philosophy and some essential construction details are given. The operating experience of the last 6 months since completion of the system is communicated.
Observation of D+→f0(500)e+νe and Improved Measurements of D→ρe+νe
2019
Using a data sample corresponding to an integrated luminosity of 2.93 fb(-1) recorded by the BESIII detector at a center-of-mass energy of 3.773 GeV, we present an analysis of the decays D-0 -> ...
The MAMI-project
2008
In the energy region up to one GeV the "racetrack"-microtron /1/ offers an economic way to achieve a 100% duty factor e--beam with a high current (IO0~A) and a well defined energy (Ap/p ~ 10-4). Such an e--beam appears to be ideal for the experimental investigation of the nucleus: coincidence experiments of the type (e,e'x) and (e,e'xy) become possible in a wide kinematical region yielding information about the response of the nucleus to the transferred energy and momentum. By the method of bremsstrahl-tagging, for the f i r s t time, rather intensive ( few times 107/sec) photon beams with high monochromaticity and well known fluxes wi l l be available. To make the best use out of such new …
Study of the partial wave structure of π0η photoproduction on protons
2013
Abstract Analysis of the partial wave structure of γ p → π 0 η p reaction is presented in the energy region from threshold up to the total center-of-mass energy W = 1.9 GeV . Angular distributions measured with the Crystal Ball/TAPS hermetic detector system at the Mainz Microtron MAMI are expanded in terms of spherical harmonics. The relation of the extracted moments to the partial wave structure of the reaction amplitude is discussed and compared with predictions from model calculations.
A large area detector for high-energy neutrons
1992
Abstract We present design studies, results of test measurements, and Monte Carlo simulations which served as a basis for the realization of a large area neutron detector (LAND). It has a front area of 2m×2m and a depth of 1 m, and features a multilayer structure of passive converter and active scintillator material. The detector is subdivided in independently operating paddles which allow time-of-flight and position measurement. An energy resolution of ΔT n / T n =5.3% for a flight path of 15 m and an overall detection efficiency of ϵ ≈ 1 is anticipated for neutrons with T n ≈ 1 GeV. The operation of LAND at the SIS facility of GSI is described.
Unusual excitation-energy division in quasi-fission reactions between50Ti,54Cr and58Fe with207,208Pb at the barrier
1987
The MESA Experimental Program: A Laboratory for Precision Physics with Electron Scattering at Low Energy
2021
A rich experimental program is currently being prepared at a new laboratory for high-intensity electron scattering at the Mainz Energy recovering Superconducting Accelerator (MESA). The physics pro...