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Title: Dijet Angular Distributions in $$p\bar{p}$$ Collisions at $$\sqrt{s} = 1.8$$ TeV

Abstract

We present measurements of diet angular distributions for events with two or more jets produced in $$p\bar{p}$$ collisions at the Fermilab Tevatron Collider at $$\sqrt{s}$$ = 1.8 TeV. The distribution of the scattering angle of a parton in the center-of mass reflects the dynamics of the interaction of two partons. This distribution was measured for different fixed regions of the diet invariant mass, in particular: 260 < $$M_{jj}$$ < 425, 475 < $$M_{jj}$$ < 635, $$M_{jj}$$ > 550, and $$M_{jj}$$ > 635 GeV / $c^2$ • Because the dijet angular distribution is expected to be relatively insensitive to the parton distribution within a proton, we can measure the properties of parton parton interactions without being concerned with the inability to calculate quantitative aspects of the substructure of the proton. We find that the next-to-leading order predictions of Perturbative Quantum Chromodynamics (QCD) show good agreement with the observed dijet angular distributions for all four mass ranges. At dijet invariant masses of greater than $$ \sim 500$$ GeV / $c^2$, the dijet angular distribution becomes sensitive to any new contact interactions originating from possible quark compositeness. In order to search for evidence that quarks are not point-like objects, but are rather bound states of more fundamental particles, we compared the predicted angular distribution with that measured in data for the mass range of $$M_{jj}$$ > 550 GeV /$c^2$. There was no departure from the expectations of next-to-leading-order Perturbative QCD, and we have used that to place a limit on the interaction scale for quark compositeness as $$\Lambda$$ > 1.8 TeV.

Authors:
 [1]
+ Show Author Affiliations
  1. Univ. of Rochester, NY (United States)
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1372333
Report Number(s):
FERMILAB-THESIS-1996-08; UMI-97-19940-MC; RX-1591 (ROCHESTER)
428631
DOE Contract Number:
AC02-07CH11359
Resource Type:
Thesis/Dissertation
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Citation Formats

Fatyga, Mary Kathryn. Dijet Angular Distributions in $p\bar{p}$ Collisions at $\sqrt{s} = 1.8$ TeV. United States: N. p., 1996. Web. doi:10.2172/1372333.
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Fatyga, Mary Kathryn. Dijet Angular Distributions in $p\bar{p}$ Collisions at $\sqrt{s} = 1.8$ TeV. United States. doi:10.2172/1372333.
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Fatyga, Mary Kathryn. Mon . "Dijet Angular Distributions in $p\bar{p}$ Collisions at $\sqrt{s} = 1.8$ TeV". United States. doi:10.2172/1372333. https://www.osti.gov/servlets/purl/1372333.
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@article{osti_1372333,
title = {Dijet Angular Distributions in $p\bar{p}$ Collisions at $\sqrt{s} = 1.8$ TeV},
author = {Fatyga, Mary Kathryn},
abstractNote = {We present measurements of diet angular distributions for events with two or more jets produced in $p\bar{p}$ collisions at the Fermilab Tevatron Collider at $\sqrt{s}$ = 1.8 TeV. The distribution of the scattering angle of a parton in the center-of mass reflects the dynamics of the interaction of two partons. This distribution was measured for different fixed regions of the diet invariant mass, in particular: 260 < $M_{jj}$ < 425, 475 < $M_{jj}$ < 635, $M_{jj}$ > 550, and $M_{jj}$ > 635 GeV / $c^2$ • Because the dijet angular distribution is expected to be relatively insensitive to the parton distribution within a proton, we can measure the properties of parton parton interactions without being concerned with the inability to calculate quantitative aspects of the substructure of the proton. We find that the next-to-leading order predictions of Perturbative Quantum Chromodynamics (QCD) show good agreement with the observed dijet angular distributions for all four mass ranges. At dijet invariant masses of greater than $ \sim 500$ GeV / $c^2$, the dijet angular distribution becomes sensitive to any new contact interactions originating from possible quark compositeness. In order to search for evidence that quarks are not point-like objects, but are rather bound states of more fundamental particles, we compared the predicted angular distribution with that measured in data for the mass range of $M_{jj}$ > 550 GeV /$c^2$. There was no departure from the expectations of next-to-leading-order Perturbative QCD, and we have used that to place a limit on the interaction scale for quark compositeness as $\Lambda$ > 1.8 TeV.},
doi = {10.2172/1372333},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 1996},
month = {Mon Jan 01 00:00:00 EST 1996}
}
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Thesis/Dissertation:
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DOI:  10.2172/1372333
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