Search results for "Linear"

Calculation of beta-decay properties of neutron-rich nickel isotopes

1989

Gamow-Tellerβ-decay properties of neutron-rich Ni isotopes have been calculated in the RPA with Nilsson model wave functions. On the basis of the results for the known isotopes67–69Ni, half-lives and neutron-emission probabilities for70–82Ni are predicted and compared to earlier model estimates. Possible implications onr-process nucleosynthesis are discussed.

Results of the 1999 H8 beam tests of ATLAS-SCT prototypes

2001

Abstract During the August–September 1999 test beam in H8 at CERN three half-modules, equipped with different types of fast binary Front End electronics, have been tested. The results indicate that all three SCT electronics candidates satisfy ATLAS efficiency and noise occupancy requirements. In addition, a study on the effect of detector bias voltage on efficiency (ballistic deficit) is reported.

Beam study of irradiated ATLAS-SCT prototypes

2002

Abstract Prototypes of ATLAS-SCT modules with ABCD readout chips were tested in a 4 GeV/c pion beam at KEK's proton synchrotron. Of both SCT module geometries—barrel and forward—three identical modules were placed in the beam. One module of each type had been irradiated to 3×1014 protons/cm2 in the CERN PS previous to the beam test. A method has been developed to reconstruct the time-resolved shaper pulse from the binary hit information, allowing a more detailed study of the timing properties of the ABCD. The present results will be compared to a simulation of the charge collection and Front End electronics response.

Silicon microstrip detectors for the ATLAS SCT

2002

Abstract The ATLAS Semiconductor Tracker at the Large Hadron Collider (LHC) will incorporate ∼20,000 individual silicon microstrip sensors representing ∼60 m 2 of silicon. Production and delivery of the sensors is already underway and scheduled for completion by late 2002. The sensors have been optimised for operation in the harsh radiation environment of the LHC, and subjected to an extensive qualification program in which their pre- and post-irradiation characteristics have been evaluated. The sensor design features are reviewed, together with their electrical characteristics and the Quality Control procedures adopted by ATLAS during production.

WITHDRAWN: Linear Response Theory with finite-range interactions

2021

Effect of the non-gaussianity on the measurement error for the filtered 1/f noise intensity

1999

To study the nature of the 1/f noise phenomenon in conductors, we seek a tool for testing different hypotheses of 1/f noise origin. The method analyzing the noise intensity at the output of a bandpass filter is discussed for the case of non-Gaussian processes. Data on measurement error are presented for the 1/f noise intensity in GaAs films and the Gaussian white noise emulated by a computer. A numerical model of 1/f noise as the superposition of telegraph random processes has been created. This method requires further improvement to check the noise for stationarity. Some ideas of how to do that are proposed.

Effect of three-body cluster on the healing properties of the Jastrow Correlation function

1973

A variational equation for the Jastrow Correlation function is derived from the energy functional expanded up to three-body cluster terms. The asymptotic behaviour of this nonlinear equation is studied. The solutions show a healing at least of the type cos(tαr)/r2. The influence of higher cluster contributions is studied. Finally, it is discussed, how one can reduce the many-body cluster contributions to healing conditions to be used in the two-body cluster treatment.

Nonlinear dynamics in three-dimensional QED and nontrivial infrared structure

1999

In this work we consider a coupled system of Schwinger-Dyson equations for self-energy and vertex functions in QED_3. Using the concept of a semi-amputated vertex function, we manage to decouple the vertex equation and transform it in the infrared into a non-linear differential equation of Emden-Fowler type. Its solution suggests the following picture: in the absence of infrared cut-offs there is only a trivial infrared fixed-point structure in the theory. However, the presence of masses, for either fermions or photons, changes the situation drastically, leading to a mass-dependent non-trivial infrared fixed point. In this picture a dynamical mass for the fermions is found to be generated c…

On the gluon spectrum in the glasma

2010

We study the gluon distribution in nucleus-nucleus collisions in the framework of the Color-Glass-Condensate. Approximate analytical solutions are compared to numerical solutions of the non-linear Yang-Mills equations. We find that the full numerical solution can be well approximated by taking the full initial condition of the fields in Coulomb gauge and using a linearized solution for the time evolution. We also compare kt-factorized approximations to the full solution.

Translationally-Invariant Coupled-Cluster Method for Finite Systems

1997

The translational invariant formulation of the coupled-cluster method is presented here at the complete SUB(2) level for a system of nucleons treated as bosons. The correlation amplitudes are solution of a non-linear coupled system of equations. These equations have been solved for light and medium systems, considering the central but still semi-realistic nucleon-nucleon S3 interaction.