Debuncher Cooling Performance

Abstract. We present measurements of the Fermilab Debuncher momentum and transverse cooling systems. These systems use liquid helium cooled waveguide pickups and slotted waveguide kickers covering the frequency range 4-8 GHz. Keywords: Stochastic Cooling, Antiproton Beams PACS: 41.75.Lx THE FERMILAB DEBUNCHER The Fermilab Debuncher is an 8 GeV ring designed for the collection, RF debunching, and storage of anitprotons. The Tevatron Collider program requires 1e13 antiprotons for the study of proton-antiproton collisions at √ s = 1.96 TeV. Antiprotons are produced by impinging a 120 GeV proton beam on an nickel alloy target and collected through a lithium focussing lens and the Debuncher ring then stochastic stacked in the Fermilab Accumulator PERFORMANCE REQUIREMENTS The Debuncher accepts a few ×10 8 antiprotons every 2 seconds. The input beam fills the transverse aperture of the beam, consistent with a transverse emittance of 320π mm mr (95% unnormalized). At the end of the 2 second cycle, the beam is required to have transverse emittance less than 45π mm mr (95% unnormalized) in both planes (factor of 7). After bunch rotation, the 95% momentum width is approximately 60 MeV/c. At the end of the 2 second cycle, the 95% momentum width of the beam is required to be less than 6 MeV/c (factor of 10). These requirements correspond to a 6-dimensional phase space density (ρ 6d = N particles ε l ε h ε v ) increase of a factor of 500

Debuncher cooling performance

We present measurements of the Fermilab Debuncher momentum and transverse cooling systems. These systems use liquid helium cooled waveguide pickups and slotted waveguide kickers covering the frequency range 4-8 GHz

RECENT PERFORMANCE OF THE FERMILAB TEVATRON COLLIDER

ABSTRACT A year ago the Tevatron completed collider run Ia. This run was highly successful in terms of high energy physics results and accelerator performance. The various accelerator performance goals set before run Ia were either met or exceeded. Subsequently a Linac upgrade and a variety of other improvements were completed. After a very difficult start, run Ib is now well underway and the instantaneous luminosity goal set for this run has been achieved. This paper provides a brief survey of the accelerator upgrades which have contributed so far to the successful running of the Fermilab collider. The issues which have been identified as limiting accelerator performance are also presented

Transverse Beam Profile Measurement Using Scrape Scans

A scraper scan - sending a scraper through a particle beam while measuring the intensity as a function of scraper position - is a common method of determining the profile of the beam. At first glance, this seems to be a rather simple procedure. Nevertheless, some care is required in the acquisition of the data and in the analysis if one is going to achieve an accurate result

Precision Measurement of the Accumulator Beam Energy

The Antiproton Source Accumulator has been used by Fermilab experiments E760 and E835 to search for and measure the various states of charmonium below the open charm threshold. Accurate determination of the resonance parameters (mass, width, and branching ratios) of these states requires a precise measurement of the antiproton beam energy. The purpose of this report is to give a detailed description of the method that is used to accomplish a precision measurement of the antiproton beam energy

Prospects for the Simultaneous Operation of the Tevatron Collider and pp Experiments in the Antiproton Source Accumulator

This document is a slightly expanded version of a portion of the Proton Driver design report. The Proton Driver group gets the credit for the original idea of running an Accumulator experiment in the BTeV era. The work presented here is a study of the feasibility of this idea. The addition of the Recycler Ring to the Fermilab accelerator complex provides an opportunity to continue the program of {bar p}p physics in the Antiproton Source Accumulator that was started by Fermilab experiments E760 and E835. The operational scenario presented here utilizes the Recycler Ring as an antiproton bank from which the colliders makes 'withdrawals' as needed to maintain the required luminosity in the Tevatron. The Accumulator is only needed to re-supply the bank in between withdrawals. When the {anti p} stacking rate is sufficiently high, and the luminosity requirements of the Collider experiments are sufficiently low, there will be time between Collider fills and subsequent refilling of the recycler to deliver beam to an experiment in the Accumulator. In the scenario envisioned here, the impact of the Accumulator experiment on the luminosity delivered to the Collider experiments is very small. If the Run II antiproton stacking rate goals are met, the operational conditions required for running Accumulator based experiments will be met during the BTeV era. A simple model of the operation of the Fermilab accelerator complex for BTeV and an experiment in the Accumulator has been developed. The model makes predictions of the rate at which luminosity is delivered to BTeV and an Accumulator experiment. This model was used to examine the impact of the proton driver on this experimental program

Transverse Emittance Growth in the Fermilab Antiproton Accumulator with High-Current Antiproton Stacks

Transverse emittance growth due to coherent instabilities in the Fermilab antiproton accumulator imposes a limit on the number of antiprotons which can be stacked and subsequently transferred to the collider. Consequences, the diagnosis and control of these phenomena has been required to further increase the luminosity of the collider. In this paper they present an overview of the techniques by which these instabilities have been studied and the methods by which they are controlled

Measurement of Trapped Ion Pockets and Control of Ion Instabilities in the Fermilab Antiproton Accumulator

Resonant interaction of positively charged, trapped residual gas ions with a negatively charged, intense antiproton beam has been identified as the primary cause of transverse instability in the Fermilab antiproton accumulator. An upgraded ion clearing system was recently installed. This upgrade yielded a significant improvement in machine performance as well as an enhanced capability for studying trapped ion related phenomena. The operational impact and preliminary results from some initial measurements made with this system are presented herein

P-986 Letter of Intent: Medium-Energy Antiproton Physics at Fermilab

1 Fermilab has long had the world’s most intense antiproton source. Despite this, the opportunities for medium-energy antiproton physics at Fermilab have been limited in the past and — with the antiproton source now exclusively dedicated to serving the needs of the Tevatron Collider — are currently nonexistent. The anticipated shutdown of the Tevatron in 2010 presents the opportunity for a world-leading medium-energy antiproton program. We summarize the current status of the Fermilab antiproton fa-cility and review some physics topics for which the experiment we propose could make the world’s best measurements. Among these, the ones with the clearest potential for high impact and visibility are in the area of charm mixing and CP violation. Continued running of the Antiproton Source following the shutdown of the Tevatron is thus one of the simplest ways that Fermilab can restore a degree of breadth to its future research program. The impact on the rest of the program will be minor. We request a small amount of effort over the coming months in order to assess these issues in more detail