Beam sweeping system Page: 2 of 22
This report is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided to UNT Digital Library by the UNT Libraries Government Documents Department.
Extracted Text
The following text was automatically extracted from the image on this page using optical character recognition software:
INTRODUCTION
At Fermilab, antiprotons are collected from the interaction of a 120-GeV proton beam with
a solid nickel target. The Main Injector production cycle has a repetition rate of 1.5 seconds,
and a beam pulse length of 1.6 ps. The efficiency of collecting antiprotons from the target
rises as the size of the proton beam spot on the target is reduced. However at the same time
the peak energy deposition on target rises. Under Main Injector conditions (5 x 1012 protons
in a 1.6-ps pulse), the spot size will have to be increased to at least 0.25 mm to keep peak
energy deposition near current levels. To bring the density of energy deposition with a 0.1-
mm spot size down to currently-existing levels, a system to sweep the beam spot on the
target [Ref. 1] has been developed. Several upgrades have been proposed for the Main
Injector as part of the Tev33 project [Ref. 2]. These upgrades, e.g., "slip stacking", will result
in increases in proton intensity of factors of 2 to 4 above the initial intensity of 5 x 1012
protons per pulse on target in the antiproton production process. Under these conditions
sweeping becomes increasingly important, and larger sweep radii are required to restore the
antiproton yield to the level achievable at low intensity.
Figure 1 shows a layout of the upgraded target station. The upstream sweep magnets will be
installed at the end of the AP1 beamline tunnel (after quadrupole magnet PQ9B). The AP1
beamline transports and focuses the 120-GeV protons from the Main Injector onto the
target. A pair of upstream sweep magnets will sweep the 120-GeV proton beam. This
location is the focal point of the proton lithium lens, which may be necessary to focus the
120-GeV proton beam on target. Antiprotons created in the target are collected by a lithium
lens, and deflected by the pulsed magnet into the AP2 beam line for injection into the
Debuncher. A single downstream sweep magnet placed in a double module between the
collection lens and the pulsed magnet, near the focal point of the collection lens, will redirect
the 8 GeV antiprotons exiting the collection lens parallel to the AP2 beamline.
120 GeV Proton Beam
PQ9B Pulsed Magnet
" Lens ens
Upstream Target Downstream
sweep magnets sweep magnet 8 GeV Antiprotons
Figure 1. Major components in the target vault of the upgraded target station. Not shown
are the pretarget SEM and the beam dump.
Upcoming Pages
Here’s what’s next.
Search Inside
This report can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Report.
al., F.M. Bieniosek et. Beam sweeping system, report, August 8, 2000; Batavia, Illinois. (https://digital.library.unt.edu/ark:/67531/metadc702676/m1/2/: accessed April 18, 2024), University of North Texas Libraries, UNT Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.