YN scattering data: HA77
The experiment:
Various Λ p events have been recorded in an exposure of the
SLAC 82-inch bubble chamber to a 12 GeV/c K- beam.
To enhance the flux of Λ-particles a platinum target
is placed inside the bubble chamber.
500000 photographs were scanned.
A total number of 992 (in)elastic events are analyzed.
Most of this experiment and some of the data were already
presented in HA74.
The data:
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Λ p → Λ p
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total elastic cross section (SGT)
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momentum range number of SGT [mb]
[MeV/c] events
400 - 1200 ) 14.8 +/- 1.6
1200 - 1800 ) 17.5 +/- 1.7
1800 - 2600 ) 17.1 +/- 1.7
2600 - 3600 ) 584 15.3 +/- 1.5
3600 - 4900 ) 11.4 +/- 1.3
4900 - 6900 ) 8.6 +/- 1.2
6900 - 10000 ) 6.5 +/- 1.2
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|
or
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momentum range number of SGT [mb]
[MeV/c] events
300 - 400 17.2 +/- 8.6
400 - 500 26.9 +/- 7.8
500 - 600 7.0 +/- 4.0
600 - 700 9.0 +/- 4.0
700 - 800 13.6 +/- 4.5
800 - 900 11.3 +/- 3.6
900 - 1000 11.3 +/- 3.8
1000 - 1100 21.1 +/- 4.8
1100 - 1200 14.0 +/- 3.4
1200 - 1300 9.6 +/- 2.9
1300 - 1400 13.5 +/- 3.4
1400 - 1500 26.0 +/- 4.8
1500 - 1600 16.4 +/- 3.7
1600 - 1700 15.9 +/- 4.1
1700 - 1800 23.5 +/- 5.0
1800 - 1900 23.3 +/- 6.0
1900 - 2000 19.8 +/- 4.4
2000 - 2100 20.1 +/- 5.6
2100 - 2200 16.3 +/- 4.5
2200 - 2300 17.6 +/- 5.1
2300 - 2400 18.0 +/- 4.8
2400 - 2500 9.6 +/- 3.4
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|
Λ p → Σ0 p
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total cross section (SGT)
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|
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momentum range number of SGT [mb]
[MeV/c] events
640 - 800 ) 8.0 +/- 4.0
800 - 1000 ) 8.5 +/- 3.0
1000 - 1200 ) 35 6.8 +/- 2.5
1200 - 1500 ) 4.8 +/- 2.0
1500 - 2500 ) 1.5 +/- 1.0
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Notes:
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The Λ p elastic cross sections were taken from Appendix IX
in HA74.
The Λ p → Σ0 p
total cross
sections
were taken from the RAL database; read from graphs.
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Some information is given on angular distributions.
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Λ polarization is determined. From events with 1 - 4 GeV/c and
0.3 < cos(theta) < 0.95 and the 'known' Λ decay asymmetry
a value for averaged P = 0.03 +/- 0.12 is found.
-
Some Ξ p events were seen.
