123038174
Excitation characteristics of Fermilab Main Injector dipoles and magnet assignment to reduce closed orbit errors
The Fermilab Main Injector project is building 344 dipoles, produced from steel with varying magnetic properties. The strategies for assigning dipoles, based upon their strength characteristics, are discussed. The closed orbit errors due to the strength variations are expected to be small in comparison to alignment errors.
45590013
Indication of pionic-atom anomalies in pion-nucleus elastic scattering.
Elastic cross sections for the scattering of positive and negative pions from /sup 58/Ni were measured at 30 MeV incident pion energy. Statistical errors of +- 3% and normalization errors of +- 6% were achieved. These data appear to confirm the theoretical construct that the physics which explains anomalously small shifts and widths in pionic atoms would be manifested in low energy pion-nucleus elastic scattering. The data show good agreement with the cross sections calculated assuming s and p partial waves are anomalous. Here anomalous refers to partial waves that are calculated from an optical potential which reproduces anomalously small level shifts and widths in pionic atoms. Conventional optical potentials do not agree as well with both the ..pi../sup +/ and ..pi../sup -/ data. Various conventional possibilities such as a larger neutron radius than proton radius in the nuclear density were tried, but these did not result in good agreement with the data.
42818936
Summary of the TeV 33 Working Group
This summary of the TeV33 working group at Snowmass reports on work in the areas of Tevatron store parameters, the beam-beam interaction, Main Injector intensity (slip stacking), antiproton production, and electron cooling. I. OVERVIEW OF TEV33 The goal of the TeV33 project is to develop a plan for the Fermilab Tevatron Collider beyond the year 2000 when the Main Injector project will be finished and collider Run II is expected to be well underway. The TeV2000 committee report [1] suggests a goal of 30 fb of proton-antiproton collisions at 2 TeV in the center of mass system by the year 2006. The physics potential of such a data sample is summarized in the committee’s report and is described in more detail in the report of the TeV2000 Study Group [2]. The goal of obtaining a sample of 30 fb of protonantiproton collisions is widely believed to be technically feasible, but it is uncertain whether it can be achieved within the likely fiscal and schedule constraints. An upgrade to a higher energy or a higher luminosity proton-proton collider is also technically possible but, based on performance, cost, and schedule considerations, is judged to be an unrealistic competitor for the Large Hadron Collider (LHC). The purpose of the TeV33 group and, in particular, the Snowmass study group, is to develop a realistic plan for TeV33 that can form the basis for future decisions. The TeV33 project assumes the successful completion of the Main Injector project and other upgrade projects that are associated with Run II. Some of the important elements of the Run II upgrade are: 1. Main Injector with both physical and dynamic apertures greatly exceeding those available with the existing Main Ring. 2. Antiproton recovery, including the construction of a “Recycler” ring in the Main Injector tunnel. 3. Antiproton source improvements in targeting and beam cooling. While the details of the TeV33 plan are not well defined, many of the major considerations are already clear. These are: 1. The antiproton production rate must be improved by about a factor of 5. 2. The antiproton cooling must be improved to accommodate the increased flux. The current plan is to use a. 4-8 GHz stochastic cooling in the existing Debuncher and Accumulator Rings, and b. electron cooling in the Recycler Ring. 3. The existing detector technology (with modest upgrades) must be capable of analyzing the collisions for rare processes. The important considerations for the accelerator are: a. Limiting the number of interactions per crossing to a sufficiently small value by using roughly 100 bunches in the Tevatron, b. Reducing the peak luminosity (luminosity leveling) to further reduce the number of interactions per crossing, and c. Maintaining low backgrounds. 4. The proton and antiproton beams must be kept well separated in the Tevatron except at the desired collision points to avoid the adverse effects of the beam-beam interaction. Obtaining adequate separation becomes increasingly difficult as the number of bunches is increased to 100 or more bunches. At Snowmass we developed some of the aspects of the TeV33 plan, but not all the important issues were covered. This paper is intended to report the work completed in conjunction with Snowmass study, and is not a balanced presentation of the current thinking on all the important elements of the TeV33 project. II. ELEMENTS OF TEV33 A. Tevatron Store Parameters The performance of a TeV33 scenario is determined by the average production rate of events that can be analyzed to study interesting physics processes. The study described below considered various initial store parameters and calculated the dependence of the integrated luminosity on several possible choices of parameters. The more delicate question of whether the events produced could be analyzed by a given detector was not considered. 1. The Luminosity Calculation It is straight-forward to calculate the luminosity (L) by integrating the beam phase-space distributions. A relatively compact expression can be obtained when the distributions are assumed to be gaussian in transverse and longitudinal positions. In this case the luminosity per interaction region is given by L = + ( ) − ( )   
54946396
Study of stability of beam in the Fermilab main injector
The Fermilab Main Injector is a new 150‐GeV proton synchrotron, designed to replace the Main Ring and improve the high energy physics potential of Fermilab. The status of the Fermilab accelerator complex upgrade will be discussed. Study of the stability of the beam in the Main injector will be discussed. Detuning and corrector schemes to improve the dynamic aperture of the Main Injector will be presented. Tune modulation caused by octupolar detuning will be discussed.
26286812
Elastic scattering of 65 MeV positive and negative pions from nickel isotopes.
Angular distributions of elastic differential cross sections were obtained at 65 MeV using positive and negative pions scattered from /sup 58/Ni, /sup 60/Ni, and /sup 64/Ni. The data were compared to predictions using the Michigan State University optical potential. These predictions are not in good agreement with the data. The negative pion cross sections are more poorly described than the positive pion cross sections. The p-italic-wave part of the potential is observed to be especially sensitive to this Coulomb-nuclear interference effect.
122682011
Magnetic field measurements of the initial Fermilab Main Injector production quadrupoles
A large sample of the 2.54-meter quadrupoles for lattice matching in the Fermilab Main Injector have been fabricated and measured. The resulting properties are reported and compared to the accelerator requirements.
119847891
The 2.5PN linear momentum flux and associated recoil from inspiralling compact binaries in quasi-circular orbits: Nonspinning case
Anisotropic emission of gravitational waves (GWs) from inspiralling compact binaries leads to the loss of linear momentum and hence gravitational recoil of the system. The loss rate of linear momentum in the far-zone of the source (a nonspinning binary system of black holes in quasicircular orbit) is investigated at the 2.5 post-Newtonian (PN) order and used to provide an analytical expression in harmonic coordinates for the 2.5PN accurate recoil velocity of the binary accumulated in the inspiral phase. We find that the recoil velocity at the end of the inspiral phase (i.e at the innermost stable circular orbit (ISCO)) is maximum for a binary with symmetric mass ratio of \nu~0.2 and is roughly about ~4.58 km/s. Going beyond inspiral, we also provide an estimate of the more important contribution to the recoil velocity from the plunge phase. Again the recoil velocity at the end of the plunge, involving contributions both from inspiral and plunge phase, is maximum for a binary with \nu~0.2 and is of the order of ~180 km/s.