Pion correlations as a function of atomic mass in heavy ion collisions Page: 36 of 130
Pages: (120 p)View a full description of this report.
Extracted Text
The following text was automatically extracted from the image on this page using optical character recognition software:
CHAPTER 4. APPARATUS
in Figs. 4.1 xnd 4.2) to give 17 possible overlaps. The staggering gives the finest possible
granularity for the number of counters, which becomes finer towards the high momentum
end (the downstream end) of the array. Some of these counters were first used in 1979,
and the pulse height resolution has degraded noticeably in the older counters. This was
considered acceptable for this experiment since the time of flight information alone can
give particle identification for most of the accepted moment.
Downstream of the target, and not on the flight path of the pions, is an ion chamber
used to monitor the beam intensity[1]. The output Is passed to an Ortec 439 current
integrator and then to the CAMAC where it is the recorded by the computer.
The signals from the various parts of the experiment were lead out of the experimen-
tal area to the electronics shack, were the trigger logic is made. The remainder of the
description of the electronics i:; given in the next section.
The acceptance of the spectrometer for the Fe setup is given on a rapidity vs. PL plot
in Fig. 4.3. The data shown are Monte Carlo data, with one track per event, weighted to
reflect the particle emission probability[39, 40]. The figure contains both the 45* and the
0" acceptances. The lines marked "A" are the lower of the two momentum cuts employed
for each of the two acceptances. The lines marked 'B" are the higher of the two momentum
cuts employed. These cuts are explained in detail in Chapter 6, and the values will be
repeated here. For the 45* data, the cuts were Ilp. > 100 MeV/c and I > 150 MeV/c.
For the 01 data the cuts were Irbil > 50 MeV/c and Ilf.il > 100 MeV/c. Table 4.4
gives the corresponding spectrometer characteristics.
gave Ii,,, I accepted Solid Angle
~ 00 (0",32") (100, 400) MeV/c 12 mar
.~ 45" (91*,106*) (100, 600) MeV/c 29 msr
Table 4.4: Spectrometer characteristics for the Fe setups.
Table 4.5 gives the locations of the effective edges of the magnets, and the centers
of the wire chambers. Using these positions, the field values from Table 4.2 and the
effective edge approximation, one can reproduce the acceptance of the spectrometer. The
coordinate system used is: the beam direction is -9, i is vertical and i is perpendicular
to the beam direction. The values are for the Ar/Nb setup, the values for the Fe set up26
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.
Chacon, A.D. Pion correlations as a function of atomic mass in heavy ion collisions, report, November 26, 1989; Berkeley, California. (https://digital.library.unt.edu/ark:/67531/metadc1055804/m1/36/: accessed July 18, 2024), University of North Texas Libraries, UNT Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.