Measuring the Supersymmetry Lagrangian

The parameters of the supersymmetry Lagrangian are the place where experiment and theory will meet. We show that measuring them is harder than has been thought, particularly because of large unavoidable dependences on phases. Measurements are only guaranteed if a lepton collider with a polarized beam and sufficient energy to produce the relevant sparticles is available. Current limits on superpartner masses, WIMPs, and the supersymmetric Higgs are not general, and need re-evaluation. We also tentatively define the MRM (Minimum Reasonable Model), whose parameters may be measurable at LEP, FNAL and LHC.Comment: 10 pages, 1 figure; a typographical error corrected in eq. (1) and one reference adde

Fine-Tuning Constraints on Supergravity Models

We discuss fine-tuning constraints on supergravity models. The tightest constraints come from the experimental mass limits on two key particles: the lightest CP even Higgs boson and the gluino. We also include the lightest chargino which is relevant when universal gaugino masses are assumed. For each of these particles we show how fine-tuning increases with the experimental mass limit, for four types of supergravity model: minimal supergravity, no-scale supergravity (relaxing the universal gaugino mass assumption), D-brane models and anomaly mediated supersymmetry breaking models. Among these models, the D-brane model is less fine tuned.The experimental propects for an early discovery of Higgs and supersymmetry at LEP and the Tevatron are discussed in this framework.Comment: 17 pages, Latex, including 5 eps figure

Implications of Supersymmetry Phases for Higgs Boson Signals and Limits

We study the supersymmetry parameter region excluded if no Higgs is found at LEP, and the region allowed if a Higgs boson is found at LEP. We describe the full seven parameter structure of Higgs sector. When supersymmetry phases are included, $\tan \beta$ greater than or equal to 2 is always allowed, and the lower limit on lightest Higgs mass if no signal is found is about 20% lower than in the Standard Model and about 10% lower than in the MSSM with phases set to 0, $\pi$Comment: 11 papges, 2 figure

Sphenomenology --- An Overview, with a Focus on a Higgsino LSP World, and on Eventual Tests of String Theory

In this talk, as requested, I begin with a overview and with some basic reminders about how evidence for supersymmetry in nature might appear -- in particular, how SUSY signatures are never clear so it is difficult to search for them without major theoretical input. Models can be usefully categorized phenomenologically by naming their LSP -- that is, once the LSP is approximately fixed so is the behavior of the observables, and the resulting behavior is generally very different for different LSPs. Next I compare the three main LSP-models (gravitino, bino, higgsino). Hints from data suggest taking the higgsino-LSP world very seriously, so I focus on it, and describe its successful prediction of reported events from the 1996 LEP runs. SUSY signatures in the $\tilde h$ LSP world are very different from those that are usually studied. Then I briefly discuss how to measure the parameters of the effective Lagrangian from collider and decay data. Finally I turn to how data will test and help extract the implications of string theories.Comment: Uses espcrc2.st

Naturalness Implications of LEP Results

We analyse the fine-tuning constraints arising from absence of superpartners at LEP, without strong universality assumptions. We show that such constraints do not imply that charginos or neutralinos should have been seen at LEP, contrary to the usual arguments. They do however imply relatively light gluinos (m_{\tilde g} \lsim 350 GeV) and/or a relation between the soft-breaking SU(3) gaugino mass and Higgs soft mass $m_{H_U}$. The LEP limit on the Higgs mass is significant, especially at low $\tan \beta$, and we investigate to what extent this provides evidence for both a lighter gluino and correlations between soft masses.Comment: 22 pages, Latex, including 2 eps figure

Implications of the Partial Width Z->bb for Supersymmetry Searches and Model-Building

Assuming that the actual values of the top quark mass at FNAL and of the ratio of partial widths Z->bb/Z->hadrons at LEP are within their current one-sigma reported ranges, we present a No-Lose Theorem for superpartner searches at LEP II and an upgraded Tevatron. We impose only two theoretical assumptions: the Lagrangian is that of the Minimal Supersymmetric Standard Model with arbitrary soft-breaking terms, and all couplings remain perturbative up to scales of order 10^16 GeV; there are no assumptions about the soft SUSY breaking parameters, proton decay, cosmology, etc. In particular, if the LEP and FNAL values hold up and supersymmetry is responsible for the discrepancy with the SM prediction of the partial width of Z->bb, then we must have charginos and/or top squarks observable at the upgraded machines. Furthermore, little deviation from the SM is predicted within "super-unified" SUSY. Finally, it appears to be extremely difficult to find any unified MSSM model, regardless of the form of soft SUSY breaking, that can explain the partial width for large tan(beta); in particular, no model with top-bottom-tau Yukawa coupling unification appears to be consistent with the experiments.Comment: 15 pages, University of Michigan preprint UM-TH-94-23. LaTeX file with 4 uuencoded figures sent separately. Compressed PS file (114Kb) available by anonymous FTP from 141.211.96.66 in /pub/preprints/UM-TH-94-23.ps.

Right-Handed New Physics Remains Strangely Beautiful

Current data on CP violation in B_d -> eta' K_S and B_d -> phi K_S, taken literally, suggest new physics contributions in b -> s transitions. Despite a claim to the contrary, we point out that right-handed operators with a single weak phase can account for both deviations thanks to the two-fold ambiguity in the extraction of the weak phase from the corresponding CP-asymmetry. This observation is welcome since large mixing in the right-handed sector is favored by many GUT models and frameworks which address the flavor puzzle. There are also interesting correlations with the B_s system which provide a way to test this scenario in the near future.Comment: 7 pages, 9 figures; published version: added 1 reference and 1 clarificatio

Neighborhood disadvantage across the transition from adolescence to adulthood and risk of metabolic syndrome

This study investigates the association between neighborhood disadvantage from adolescence to young adulthood and metabolic syndrome using a life course epidemiology framework. Data from the United States-based National Longitudinal Study of Adolescent to Adult Health (n = 9500)and a structural equation modeling approach were used to test neighborhood disadvantage across adolescence, emerging adulthood, and young adulthood in relation to metabolic syndrome. Adolescent neighborhood disadvantage was directly associated with metabolic syndrome in young adulthood. Evidence supporting an indirect association between adolescent neighborhood disadvantage and adult metabolic syndrome was not supported. Efforts to improve cardiometabolic health may benefit from strategies earlier in life

Could Large CP Violation Be Detected at Colliders?

We argue that CP--violation effects below a few tenths of a percent are probably undetectable at hadron and electron colliders. Thus only operators whose contributions interfere with tree--level Standard Model amplitudes are detectable. We list these operators for Standard Model external particles and some two and three body final state reactions that could show detectable effects. These could test electroweak baryogenesis scenarios.Comment: 11pp, LaTeX, UM--TH--92--27(massaged to make TeX output cleaner), no picture

Searching for a Light Stop at the Tevatron

We describe a method to help the search for a light stop squark [M(stop) + M(LSP) < M(top)] at the Fermilab Tevatron. Traditional search methods rely upon a series of stringent background-reducing cuts which, unfortunately, leave very few signal events given the present data set. To avoid this difficulty, we instead suggest using a milder set of cuts, combined with a "superweight," whose purpose is to discriminate between signal and background events. The superweight consists of a sum of terms, each of which are either zero or one. The terms are assigned event-by-event depending upon the values of various observables. We suggest a method for choosing the observables as well as the criteria used to assign the values such that the superweight is "large" for the supersymmetric signal and "small" for the standard model background. For illustration, we mainly consider the detection of stops coming from top decay, making our analysis especially relevant to the W+2 jets top sample.Comment: 45 pages, revtex, 15 figures included. Final version, as will appear in Phys. Rev. D. Contains an expanded introduction plus a few additional reference