Search For the Higgs H o ->ZZ*->bbll Philip Davis (NMSU) Mentor: Dr. Teuscher (U of T) Aided by Christophe Le Maner (U of T)

Invariant Mass of Higgs for m H of 150 GeV before Cuts Electron (shown) and Muon System Luminosity 30 fb -1 Mass Analysis on m H of 150 GeV tt ZZ Zbb bb Zee Zmm Higgs Signal Back Grounds

Intro Previous analysis of this decay channel done by Christophe Le Maner  Monte Carlo Data created using Pythia, MCatNLO, and AcerMC  New Monte Carlo Data simulated after first analysis What I did  Try to recreate old analysis  Apply my own analysis  Create automated system of applying cuts

Cuts for m H of 150 GeV on Electron Channel (Previous Analysis) CutValue Zero total charge on lepton pair Charge e1 + e2 = 0 Inv. Mass of Virtual Z System10 < m Z < 65 GeV Inv. Mass of Z System50 < m Z < 110 GeV η1 and η2 of VBF jets opposite dir.η1*η2 < 0 Diff. in pseudo rapidity of VBF jets|∆η| > 3.3 Mass of VBF jetsm jj > 300 GeV Missing PtPt miss < 25 GeV b jet and lepton in between VBF jets Mass window130 < m H < 170 GeV

Repeating Previous Analysis (New Data) Higgs MassSS/√BGRelative Error H130 (ee channel) % H150 (ee chanel) % H130 ( μμ chanel) % H150 ( μμ chanel) % Previous Analysis - Christophe Le Maner Higgs MassSS/√BG H130 (ee channel) H150 (ee chanel) H130 ( μμ chanel) H150 ( μμ chanel)

Cuts for m H of 150 GeV on Electron Channel CutValue 2 b-jets required Invariant mass of di-electron System 10 < m ee < 65 GeV Missing PtPt < 25 GeV Diff. in pseudo rapidity of VBF jets|∆η| > 3.3 Sum of Pt of VBF JetsPt 1 + Pt 2 > 90 GeV Mass of VBF jetsm jj > 300 GeV η1 and η2 opposite dir.η1*η2 < 0 Inv. Mass of Z System50 < m Z < 110 GeV Zero total charge on lepton pairCharge e1 + e2 = 0 Mass window130 < m H < 170 GeV

Histograms Gev 50 < m z o < 110 GeV 10 < mee < 65 GeV (constrain leptons to come from Virtual Z)

Missing Pt < 25 GeV GeV Mass of VBF jets > 300 GeV GeV More Histograms

Pt of Forward Jet 1 Vs. Jet 2 Sum > 90 GeV Pt of 2 jet (GeV) Pt of 1 jet (GeV)

New Cuts Higgs MassSS/√BGRelative Error H130 (ee channel) % H150 (ee chanel) % H130 ( μμ chanel) % H150 ( μμ chanel) % Problem with H130 data is that it start out with low number of events Increase in S/√BG from old cuts Increase in Relative Error from old cuts H150 data gives better results but still low significance Signal Rejection ~ 21% (H150 ee chanel) Background Rejection ~ 0.028% (H150 ee chanel)

Signal after Cuts Higgs Signal

Fully Automated Cut System Program run cuts over a range of values and stores results to root file. Results searched my another program to return cuts with best outputs. Only used old data on this program.  Relative Error usually about 100%  Next step should be to uses this method on new data

Protection Circuit for LVPS

Background Front end electronics of the Tile Calorimeter in ATLAS are kept in drawers as seen above. TileCal has 256 of these drawers Each drawer requires its own power supply.

Background/Problem The Low Voltage Power Supply (LVPS) converts a 200 V DC power supply to 8 DC voltages required by the front end electronics in the TileCal. When installed in the pit the LVPS has burned up components due to voltages going over their ratings. Important issue for LHCC

Solution Regulating Circuit that monitors the 8 voltages and currents going to the detector.  Monitors for under-voltage, over-voltage, and over-current. Circuit switches power off in TileCal when voltage or current goes out of range. Voltages put into two groups. High Voltage side and Digitizer side. High Voltage When one side is triggered the other side can still operate.

Circuit Simulation Circuit simulated in Quartus II Implemented in Embedded Local Monitor Board (ELMB) in the LVPS

Circuit Explanation Redundancy circuit 32 bit Shift Register Current input Voltage input Trip Outputs

Wave form of Inputs and Outputs Outputs of Digitizer and High Voltage Trigger Output of Shift Register

Special Thanks Dr. Teuscher Christophe Le Maner CERN University of Michigan NSF Ford

Backup slides

Cut Table Cuts with weights for Muon Channel Cut mH tt Zbb ZZ Zee Zmm bb Total BG Signal/sqrt(BG) Total number of events Total number bjets invariant mass of muons missing pt Delta of eta for VBF jets sum pt of vbf jets mass of vbf jets eta1*eta2< zed mass even charge mass window Cuts with weights for Electron Channel Cut mH tt Zbb ZZ Zee Zmm bb Total BG Signal/sqrt(BG) Total number of events number of bjets invariant mass of electrons missing pt Delta of eta for VBF jets sum pt of vbf jets mass of vbf jets eta1*eta2< zed mass even charge mass window

Output of HV and Digitizer Pins Wave of output pins Shows that each input works and that the corresponding output pin is triggered.