18432051
Self consistent monte Carlo method to study CSR effects in bunch compressors
In this paper we report on the results of a self-consistent calculation of CSR effects on a particle bunch moving through the benchmark Zeuthen bunch compressors. The theoretical framework is based on a 4D Vlasov-Maxwell approach including shielding from the vacuum chamber. We calculate the fields in the lab frame, where time is the independent variable, and evolve the phase space density/points in the beam frame, where arc length along a reference orbit is the independent variable. We also discuss three approaches, the unperturbed source model (UPS), the self consistent Monte Carlo (SCMC) method and the method of local characteristics.
2396816
Progress on a Vlasov Treatment of Coherent Synchrotron Radiation from Arbitrary Planar Orbits
We report on our progress in the development of a fully self-consistent Vlasov treatment of coherent synchrotron radiation (CSR) effects on particle bunches traveling on arbitrary planar orbits. First we outline our Vlasov approach and the approximation we are currently studying. Then we discuss recent numerical results for a benchmark model studied extensively with codes by several authors.
55035317
COMPARISON OF 1D AND 2D CSR MODELS WITH APPLICATION TO THE FERMI @ ELETTRA BUNCH COMPRESSORS
We compare our 2D mean field (Vlasov-Maxwell) treatment of coherent synchrotron radiation (CSR) effects with 1D approximations of the CSR force which are commonly implemented in CSR codes. In our model we track particles in 4D phase space and calculate 2D forces [1]. The major cost in our calculation is the computation of the 2D force. To speed up the computation and improve 1D models we also investigate approximations to our exact 2D force. As an application, we present numerical results for the Fermi{at}Elettra first bunch compressor with the configuration described in [1].
189808711
Summary of Coherent Theory and Simulations Session
There were two types of talks which we attempt to summarize. Section 2 discusses the analytical talks and Section 3 the simulation talks. We hope that at least our summary will have the flavor of the session and serve as a reasonable pointer to papers in the proceedings and elsewhere. We take this opportunity to thank the participants of this session for making it an interesting one. The major emphasis in this session was on codes and we have tried to give an overview of basic computational strategies in Section 3 before highlighting the talks.
122076282
Deflection of GeV particle beams by channeling in bent crystal planes of constant curvature
15693839
Self-consistent computation of electromagnetic fields and phase space densities for particles on curved planar orbits
We discuss our progress on the self-consistent calculation of the 4D phase space density (PSD) and electromagnetic fields in a Vlasov-Maxwell formulation. We emphasize coherent synchrotron radiation (CSR) from arbitrary curved planar orbits, with shielding from the vacuum chamber, but space charge forces are naturally included. Our focus on the Vlasov equation will provide simulations with lower numerical/statistical noise than standard PIC methods, and will allow the study of issues such as emittance degradation and microbunching due to space charge and CSR in bunch compressors. The fields excited by the bunch are computed in the lab frame from a new double integral formula. The field formula is derived from retarded potentials by changes of variables. It is singularity-free and requires no computation of retarded times. Ultimately, the Vlasov equation will be integrated in beam frame coordinates using our method of local characteristics. As an important intermediate step, we have developed a "self-consistent Monte Carlo algorithm", and a corresponding parallel code. This gives an accurate representation of the source and will help in understanding the PSD support. In addition we have (1) studied carefully a 2D phase space Vlasov analogue and (2) derived an improved expression of the field of a 1D charge/current distribution which accounts for the interference of different bends and other effects usually neglected. Bunch compressors will be emphasized.
121294791
Background rates in silicon detectors used in uranium calorimeters
Abstract Ion-implanted silicon diode detectors have been used to establish counting rates from radioactive decays of uranium. The measurements allow the estimation of background counting rates in uranium-silicon calorimeters used in high energy physics experiments.
114249657
Development and evaluation of silicon drift chambers
126030076
Measurement of B_s Oscillations and CP Violation Results from D0
We present a measurement of the B{sub s}{sup 0} - B{sub s}{sup 0} oscillation frequency, {Delta}m{sub s}, using a combination of semi-leptonic and hadronic B{sub s} decay candidates selected from data collected by the D0 Experiment at the Fermilab Tevatron. We also present several results on CP violation, including an improved measurement of the B{sub s} CP-violating phase from a flavor-tagged analysis of B{sub s}{sup 0} {yields} J/{psi} + {phi} decays.
118930627
TOP QUARK PHYSICS RESULTS FROM DØ
We describe recent measurements of the ttbar production cross section and the mass of the top quark from the D0 Collaboration.
16901067
W Boson Physics at the Fermilab Tevatron
We present electroweak physics results from the D0 and CDF experiments using data from p \bar p collisions at \sqrt s = 1.8 TeV. Measurements of the cross sections times branching ratios for W and Z production, the inclusive width of the W boson and the W boson mass are presented. Direct tests of the WW\gamma and WWZ trilinear gauge boson couplings are also presented based on studies of diboson production.