Determining the Dark Matter Relic Density at the LHC

(Maintained by Alfredo Gurrola and Abram Krislock)
Return to home page.

  1. Versions of the Dark Matter Relic Density Paper (Dr. Kamon's webpage)
  2. Dark Matter Relic Density Paper: Figure 1
  3. Dark Matter Relic Density Paper: Figure 2
  4. Dark Matter Relic Density Paper: Figure 3
  5. Dark Matter Relic Density Paper: Figure 4
  6. Dark Matter Relic Density Paper: Figure 5
  7. Dark Matter Relic Density Uncertainties VS. Luminosity ()
  8. SUSY mass uncertainties at 10 fb-1 ()
  9. mSUGRA parameter uncertainties at 10 fb-1 ()
  10. Dark Matter Relic Density Paper: Extras
  11. 1σ error ellipses for the mSUGRA parameters at 10 fb-1
  12. APS talk Oct. 2007 ()
  13. Slides used for LHC Pheno. Meeting on 01/11/08 ()

    Slide 8
    Slide 9
    Slide 11
    Slide 12
    Slide 13
    Slide 14
    Slide 15
    Slide 16
    Slide 18
    Slide 19
    Slide 20
    Slide 21
    Slide 23
    Slide 24
    Slide 25
  14. Plots for jττ Mass Study ...
    ()
)
  • Uncertainty in ΔM vs. ΔM (12 fb-1) ()
  • Events per luminosity vs. gluino mass ()
  • Events per luminosity vs. ΔM for mass of gluino = 750, 850, and 950 GeV. ()
  • Uncertainty in ΔM vs. gluino mass when gluino mass is assumed to be 848.9 GeV using counting method ()
  • Uncertainty in ΔM vs. Luminosity

    We can also measure ΔM and get an uncertainty by measuring the invariant mass of two opposite-signed taus. The invariant mass of each pair is placed in a histogram from which we can calculate a mean ditau mass and an RMS of the mass peak. For very low values of ΔM and of luminosity, a clear peak cannot be found. The mean ditau mass and the RMS of the peak increase with ΔM. These correlations, combined with the lower statistics of opposite-signed pairs, produces a much larger uncertainty in the measurement of ΔM than the counting method does.

  • Number of events per luminosity in the peak using the ditau mass measurement vs. ΔM ()
  • Number of opposite-sign minus like-sign events per luminosity vs. ΔM ()
  • Number of total events and events in peak per luminosity vs. ΔM ()
  • Mean of invariant mass vs. mass difference. ()
  • Mean of invariant mass vs. mass difference for three different gluino masses. ()
  • RMS of the peak vs. ΔM in the ditau mass measurement ()
  • Uncertainty of ΔM using both the counting method and the shape fitting method ()
  • Uncertainty of ΔM vs. Luminosity using both methods ()
  • Mean of invariant mass vs. gluino mass ()
  • RMS of ditau mass peak vs. gluino mass ()
  • Events in the peak in the ditau mass measurement vs. gluino mass ()
  • Number of opposite-sign minus like-sign events per luminusity vs. gluino mass ()
  • Uncertainty in ΔM vs. gluino mass for the mass measurement method ()
  • Combined Uncertainty in ΔM vs. gluino mass for the mass measurement method and for the counting method ()

  • Curves of constant events per luminosity and of constant ditau mass ()

  • Using Monte Carlo method to get uncertainties in ΔM ()
  • Values of ΔM obtained from Monte Carlo for counting method and mass measurement method plotted against each other. ()
  • Values of ΔM and gluino mass obtained from Monte Carlo when ΔM and the gluino mass are measured at the same time. ()
  • Scatter plot of ΔM and the gluino mass obtained from Monte Carlo when ΔM and the gluino mass are measured at the same time. ()
  • Same plot as above with curves drawn for the 1-sigma region. ()
  • Now using opposite-sign minus like-sign pairs. Values of ΔM and the gluino mass obtained from Monte Carlo when ΔM and the gluino mass are measured at the same time. ()
  • Now using opposite-sign minus like-sign pairs. Scatter plot of ΔM and the gluino mass obtained from Monte Carlo when ΔM and the gluino mass are measured at the same time. ()

    If we assume that ΔM is 12 GeV, we can measure the gluino mass.
  • Uncertainty in Measurement of Gluino Mass vs. gluino mass ()

    We can do the analysis using the number of opposite-sign pairs minus like-sign pairs.
  • Number of opposite-sign pairs minus like-sign tau pairs vs. ΔM. ()

    This plot shows the Uncertainty in ΔM vs. Luminosity including the systematic error from the uncertainty in the gluino mass. We assumed the gluino mass was 850 GeV plus or minus 100 GeV, and we found the uncertainty in the number of events was approximately N.
  • Uncertainty in ΔM vs. Percent Gluino Mass Uncertainty for L = 12 ()
  • Uncertainty in ΔM vs. Percent Gluino Mass Uncertainty for L = 5 and L = 30 ()

    Plots with fake rate:
  • Number of OS - LS counts vs. fake rate. ()
  • Number of OS - LS counts vs. ΔM with a 1% fake rate. ()
  • Number of OS - LS counts vs. ΔM with a 1% fake rate looking only at ditau pairs of mass less than 100 GeV. ()
  • Uncertainty of ΔM vs. ΔM with a 1% fake rate with and without a 20% uncertainty in the fake rate. ()


  • Example Sparticle Masses for ΔM = 5.4 GeV and ΔM = 17.2 GeV ()
  • Table of mother particles for taus at ΔM = 5.4 GeV ()
  • Table of mother particles for taus at ΔM = 17.2 GeV ()
  • Counts accepted vs. mass diff. ()
  • Error of counting method and of shape fitting together ()
  • Mean of invariant mass vs. mass difference ()
  • Events vs. gluino Mass for ΔM = 12 GeV ()
  • .pdf of related plots ()
  • Missing ET vs. ET of leading jet. ()
  • ttbar background. ()


    Other ideas in progress:

  • Invariant Ditau Mass (Opposite Sign Distribution - Like Sign Distribution) ()
  • Sum ET Objects and Sum ET Objects + Missing ET ()
  • ETj1 + Missing ET and ETj1 + ETj2 + Missing ET ()

    Nikolay's plots using ATLFast:
  • Opposite-sign minus like-sign counts vs. ΔM for varying fake rates. ()
  • Opposite-sign plus like-sign counts vs. ΔM for varying fake rates. ()
  • Mean ditau mass vs. ΔM for varying fake rates. ()
  • Mass peak vs. fake rate. () -->
    (last updated on )