thinkshop

Fermi National Accelerator Laboratory
October 16 - 18, 1998

Organized by
Elizabeth H. Simmons (Boston University) 617.353.4792
Scott Willenbrock (University of Illinois) 217.333.4392
Stephen Parke (Fermilab) 630.840.4517
Chris Quigg (Fermilab) 630.840.3578

thinkshop 2

thinkshop2: the sequel, November 10-12, 2000

thinkshop Participants

General Reviews on Top-Quark Physics

Top Physics at the LHC · Report of the LHC Top Physics Working Group

In preparation for Run II of Fermilab's Tevatron Collider, we are organizing a thinkshop on top-quark physics that will bring together theorists and experimentalists from the HEP community at Fermilab and beyond. The goals of the top thinkshop are to give theorists a better understanding of the discovery potential of Tevatron Run II and to develop new experimental opportunities for the CDF and DØ detectors. The atmosphere of the top thinkshop will be informal, to foster the presentation and discussion of new ideas. We hope for a stimulating exchange that will inspire future research in both theory and experiment.

The heart of the thinkshop will be Discussion Groups modeled on Aspen workshops. The convenors (one experimentalist and one theorist for each group) will select several participants to make "five-minute" presentations, which we expect will stretch to ten minutes with interruptions and elaborations. Each of these should provoke group discussion. It is the job of the convenors to cut off speakers at the right moment, to animate discussion, and to move on to the next topic.

We welcome suggestions for thinkshop topics and for specific presentations.

Fermilab Visitor Information , Lodging , Transportation

Contributed Papers

PROGRAM

MORNING DISCUSSION GROUPS

Precision Measurements: This is mostly about mt: how to define it, the limits to measurement and interpretation, the motivation for making a measurement of this or that precision, comparing measurements of mt from different channels. List of Participants

Weak Interactions of Top: Branching fraction of top into b+W, top width and single-top cross section, measurement of |Vtb| in single-top production, the W decay angular distribution. Except for the possibility of a sequential fourth generation, we take the top to have standard weak interactions. How well can we measure these properties, and what do the measurements mean? List of Participants

Top Pair Production: Total cross section (how well can it be measured and calculated); kinematical characteristics and spin correlations; the top-antitop invariant mass spectrum; sensitivity to unconventional three-gluon couplings, etc. The motivation and rewards of these studies. List of Participants

Is it really top? Is it only top? This group explores speculations that stop is present in the top sample, that isoscalar quarks may be mixed in, etc. They should try to understand how to confirm or kill some of the exotic interpretations, and to extend the search for new particles associated with top in Run II. List of Participants

AFTERNOON DISCUSSION GROUPS

Does top have substructure? Is top as pointlike as the light quarks, or is it composite at some lower scale? What measurements will best constrain top compositeness? If the current constraints are weaker than for the other fermions, can one build a model in which the top's size is significantly larger? What are the implications for experiment? List of Participants

Does top have nonstandard gauge couplings / unusual quantum numbers? Do the gauge interactions treat all three generations of fermions similarly, or is the third generation treated differently? Explore new mechanisms for single-top production, search for gauge bosons that couple preferentially to the third generation, etc. List of Participants

Rare decays of top? Charged scalars in top decay to b + scalar; flavor-changing neutral-current decays, etc. Theoretical motivation and experimental sensitivity. List of Participants

Does top play a special role in hiding electroweak and flavor symmetry? Top condensates, variants of extended technicolor, etc. What are the experimental targets, beyond structure in the top-antitop invariant mass distribution? List of Participants