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Title: Probing supersymmetry beyond the reach of LEP2 at the Fermilab Tevatron: Low |M{sup 3}| dark matter models

Abstract

In supersymmetric models where the magnitude of the GUT scale gaugino mass parameter M{sub 3} is suppressed relative to M{sub 1} and M{sub 2}, the lightest neutralino can be a mixed higgsino-bino state with a thermal relic abundance in agreement with the WMAP central value for {omega}{sub CDM}h{sup 2} and consistent with all other phenomenological constraints. In these models, the gluino can be as light as 200 GeV without conflicting with the LEP2 bounds on the chargino mass. Thus, gluino pair production can be accessible at the Fermilab Tevatron at high rates. In this framework, gluinos decay radiatively with a large branching fraction to a gluon plus a neutralino. We find that experiments at the Fermilab Tevatron, with 5 fb{sup -1} of integrated luminosity, will be sensitive to g-tilde g-tilde production in the m{sub g-tilde}{approx}200-350 GeV range via the multi-jet+E{sub T}{sup miss} and multi-jet+l{sup +}l{sup -}+E{sub T}{sup miss} channels at the 5{sigma} level, while trilepton signatures are expected to be below this level of detectability. Dilepton mass edges from both Z-tilde{sub 2} and Z-tilde{sub 3} decays may be measurable in the dilepton+multi-jet+E{sub T}{sup miss} channel.

Authors:
 [1];  [2];  [3];  [4];  [5]
  1. Dept. of Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States)
  2. (United States)
  3. Dept. of Physics and Astronomy, University of Kansas, Lawrence, Kansas 66045 (United States)
  4. California Institute of Technology, Mail Code 106-38, Pasadena, California 91125 (United States)
  5. Dept. of Physics and Astronomy, University of Hawaii, Honolulu, Hawaii 96822 (United States)
Publication Date:
OSTI Identifier:
21011007
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevD.75.035004; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BRANCHING RATIO; FERMILAB TEVATRON; GEV RANGE; GLUONS; GRAND UNIFIED THEORY; JET MODEL; NONLUMINOUS MATTER; PAIR PRODUCTION; PARTICLE DECAY; REST MASS; SPARTICLES; SUPERSYMMETRY

Citation Formats

Baer, Howard, Dept. of Physics, Florida State University, Tallahassee, Florida 32306, Mustafayev, Azar, Profumo, Stefano, and Tata, Xerxes. Probing supersymmetry beyond the reach of LEP2 at the Fermilab Tevatron: Low |M{sup 3}| dark matter models. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.035004.
Baer, Howard, Dept. of Physics, Florida State University, Tallahassee, Florida 32306, Mustafayev, Azar, Profumo, Stefano, & Tata, Xerxes. Probing supersymmetry beyond the reach of LEP2 at the Fermilab Tevatron: Low |M{sup 3}| dark matter models. United States. doi:10.1103/PHYSREVD.75.035004.
Baer, Howard, Dept. of Physics, Florida State University, Tallahassee, Florida 32306, Mustafayev, Azar, Profumo, Stefano, and Tata, Xerxes. Thu . "Probing supersymmetry beyond the reach of LEP2 at the Fermilab Tevatron: Low |M{sup 3}| dark matter models". United States. doi:10.1103/PHYSREVD.75.035004.
@article{osti_21011007,
title = {Probing supersymmetry beyond the reach of LEP2 at the Fermilab Tevatron: Low |M{sup 3}| dark matter models},
author = {Baer, Howard and Dept. of Physics, Florida State University, Tallahassee, Florida 32306 and Mustafayev, Azar and Profumo, Stefano and Tata, Xerxes},
abstractNote = {In supersymmetric models where the magnitude of the GUT scale gaugino mass parameter M{sub 3} is suppressed relative to M{sub 1} and M{sub 2}, the lightest neutralino can be a mixed higgsino-bino state with a thermal relic abundance in agreement with the WMAP central value for {omega}{sub CDM}h{sup 2} and consistent with all other phenomenological constraints. In these models, the gluino can be as light as 200 GeV without conflicting with the LEP2 bounds on the chargino mass. Thus, gluino pair production can be accessible at the Fermilab Tevatron at high rates. In this framework, gluinos decay radiatively with a large branching fraction to a gluon plus a neutralino. We find that experiments at the Fermilab Tevatron, with 5 fb{sup -1} of integrated luminosity, will be sensitive to g-tilde g-tilde production in the m{sub g-tilde}{approx}200-350 GeV range via the multi-jet+E{sub T}{sup miss} and multi-jet+l{sup +}l{sup -}+E{sub T}{sup miss} channels at the 5{sigma} level, while trilepton signatures are expected to be below this level of detectability. Dilepton mass edges from both Z-tilde{sub 2} and Z-tilde{sub 3} decays may be measurable in the dilepton+multi-jet+E{sub T}{sup miss} channel.},
doi = {10.1103/PHYSREVD.75.035004},
journal = {Physical Review. D, Particles Fields},
number = 3,
volume = 75,
place = {United States},
year = {Thu Feb 01 00:00:00 EST 2007},
month = {Thu Feb 01 00:00:00 EST 2007}
}
  • Luminosity upgrades of the Fermilab Tevatron p{bar p} collider have been shown to allow experimental detection of a standard model (SM) Higgs boson up to m{sub H{sub SM}}{approximately}120thinspGeV via WH{sub SM}{r_arrow}l{nu}b{bar b} events. This limit nearly saturates the parameter space for many models of weak scale supersymmetry (SUSY) with a minimal particle content. It is therefore interesting to examine the SUSY Higgs reach of future Tevatron experiments. Contours are presented of Higgs boson reach for CERN LEP2 and Tevatron luminosity upgrades for three models of weak scale SUSY: the minimal supersymmetric standard model, the minimal supergravity model and a simplemore » gauge mediated SUSY breaking model. In each case we find a substantial gain in reach at the Tevatron with integrated luminosity increasing from 10thinspfb{sup {minus}1} to 25{endash}30thinspfb{sup {minus}1}. With the larger integrated luminosity, a Higgs boson search at the Tevatron should be able to probe essentially the entire parameter space of these models. While a discovery would be very exciting, a negative result would severely constrain our ideas about how weak scale supersymmetry is realized. {copyright} {ital 1998} {ital The American Physical Society}« less
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  • We quantitatively explore, in the context of the D0 detector at the Fermilab Tevatron, three very different techniques for observing delayed decays of the lightest neutralino of a simple gauge-mediated supersymmetry breaking (GMSB) model to photon plus gravitino. It is demonstrated that the delayed-decay signals considered can greatly increase the region of general GMSB parameter space for which supersymmetry can be detected. In the simple class of models considered, the combination of standard supersymmetry signals and delayed-decay signals potentially yields at least one viable signal for nearly all of the theoretically favored parameter space. The importance, for delayed-decay signal detection,more » of particular detector features and of building a simple photon detector on the roof of the D0 detector building is studied. {copyright} {ital 1998} {ital The American Physical Society}« less
  • We examine the capability of a {radical}{ital s} =2 TeV Fermilab Tevatron {ital p{bar p}} collider to discover supersymmetry, given a luminosity upgrade to amass 25 fb{sup {minus}1} of data. We compare with the corresponding reach of the Tevatron main injector (1 fb{sup {minus}1} of data). Working within the framework of minimal supergravity with gauge coupling unification and radiative electroweak symmetry breaking, we first calculate the regions of parameter space accessible via the clean trilepton signal from {ital {tilde W}}{sub 1}{ital {tilde Z}}{sub 2}{r_arrow}3{ital l}+{ital @};sE{sub {ital T}} production, with detailed event generation of both signal and major physics backgrounds.more » The trilepton signal can allow equivalent gluino masses of up to {ital m}{sub {ital {tilde g}}}{similar_to}600--700 GeV to be probed if {ital m}{sub 0} is small. If {ital m}{sub 0} is large, then {ital m}{sub {ital {tilde g}}}{similar_to}500 GeV can be probed for {mu}{lt}0; however, for {mu}{gt}0 and large values of {ital m}{sub 0}, the rate for {ital {tilde Z}}{sub 2}{r_arrow}{ital {tilde Z}}{sub 1}{ital l{bar l}} is suppressed by interference effects, and there is {ital no} reach in this channel. We also examine regions where the signal from {ital {tilde W}}{sub 1}{ital {tilde W}}{bar @}d1{r_arrow}{ital l{bar l}}+{ital @};sE{sub {ital T}} is detectable. Although this signal is background limited, it is observable in some regions where the clean trilepton signal is too small. Finally, the signal {ital {tilde W}}{sub 1}{ital {tilde Z}}{sub 2}{r_arrow}jets+{ital l{bar l}}+{ital @};sE{sub {ital T}} can confirm the clean trilepton signal in a substantial subset of the parameter space where the trilepton signal can be seen.« less