QCD-improved b{r_arrow}s{gamma} constraints on the minimal supergravity model

doi:https://doi.org/10.1103/PhysRevD.55.3201

Title: QCD-improved b{r_arrow}s{gamma} constraints on the minimal supergravity model

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Abstract

Recent advances in the QCD corrections to b{r_arrow}s{gamma} decay in the MSSM include (i) evaluation of the relevant operators, Wilson coefficients, and anomalous dimension matrix elements for the various MSSM effective theories valid at scales beyond Q=M{sub W}, (ii) calculations of most of the needed anomalous dimension matrix elements to next-to-leading order for scales m{sub b}{approx_lt}Q{lt}M{sub W}, and (iii) calculations of O({alpha}{sub s}) virtual and bremsstrahlung corrections to the b{r_arrow}s{gamma} decay operators at scale Q{approximately}m{sub b}. We assemble all these known results to gain an estimate of B(b{r_arrow}s{gamma}) for the parameter space of the minimal supergravity model (MSUGRA). We find a much reduced scale dependence of our result compared to usual leading-log evaluations. Comparison with the latest CLEO results yields stringent constraints on parameter space. Much of MSUGRA parameter space is ruled out for {mu}{lt}0, especially for large tan{beta}. We compare these results with other constraints from cosmology and nonstandard vacua. Also, we compare with expectations for discovering MSUGRA at CERN LEP 2, the Fermilab Tevatron, and the CERN LHC. {copyright} {ital 1997} {ital The American Physical Society}

Authors:

Baer, H; Brhlik, M ^[1]

Department of Physics, Florida State University, Tallahassee, Florida 32306 (United States)

Publication Date:: 1997-03-01

OSTI Identifier:: 467806

DOE Contract Number:: FG05-87ER40319

Resource Type:: Journal Article

Journal Name:: Physical Review, D

Additional Journal Information:: Journal Volume: 55; Journal Issue: 5; Other Information: PBD: Mar 1997

Country of Publication:: United States

Language:: English

Subject:: 66 PHYSICS; B QUARKS; RADIATIVE DECAY; SUPERGRAVITY; LIMITING VALUES; QUANTUM CHROMODYNAMICS; S QUARKS; ANOMALOUS DIMENSION; MATRIX ELEMENTS; MOMENTUM TRANSFER; BREMSSTRAHLUNG; CORRECTIONS; COSMOLOGY; ELECTROMAGNETIC PARTICLE DECAY

Citation Formats


                    Baer, H, and Brhlik, M. QCD-improved b{r_arrow}s{gamma} constraints on the minimal supergravity model.  United States: N. p., 1997. 
        Web.  doi:10.1103/PhysRevD.55.3201.

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                    Baer, H, & Brhlik, M. QCD-improved b{r_arrow}s{gamma} constraints on the minimal supergravity model.  United States.  https://doi.org/10.1103/PhysRevD.55.3201

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                    Baer, H, and Brhlik, M. Sat .  
        "QCD-improved b{r_arrow}s{gamma} constraints on the minimal supergravity model".  United States.  https://doi.org/10.1103/PhysRevD.55.3201.

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@article{osti_467806,

  title        = {QCD-improved b{r_arrow}s{gamma} constraints on the minimal supergravity model},

  author       = {Baer, H and Brhlik, M},

  abstractNote = {Recent advances in the QCD corrections to b{r_arrow}s{gamma} decay in the MSSM include (i) evaluation of the relevant operators, Wilson coefficients, and anomalous dimension matrix elements for the various MSSM effective theories valid at scales beyond Q=M{sub W}, (ii) calculations of most of the needed anomalous dimension matrix elements to next-to-leading order for scales m{sub b}{approx_lt}Q{lt}M{sub W}, and (iii) calculations of O({alpha}{sub s}) virtual and bremsstrahlung corrections to the b{r_arrow}s{gamma} decay operators at scale Q{approximately}m{sub b}. We assemble all these known results to gain an estimate of B(b{r_arrow}s{gamma}) for the parameter space of the minimal supergravity model (MSUGRA). We find a much reduced scale dependence of our result compared to usual leading-log evaluations. Comparison with the latest CLEO results yields stringent constraints on parameter space. Much of MSUGRA parameter space is ruled out for {mu}{lt}0, especially for large tan{beta}. We compare these results with other constraints from cosmology and nonstandard vacua. Also, we compare with expectations for discovering MSUGRA at CERN LEP 2, the Fermilab Tevatron, and the CERN LHC. {copyright} {ital 1997} {ital The American Physical Society}},

  doi          = {10.1103/PhysRevD.55.3201},

  url          = {https://www.osti.gov/biblio/467806},
  journal      = {Physical Review, D},
number       = 5,

  volume       = 55,

  place        = {United States},

  year         = {1997},

  month        = {3}

}

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