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R&D FOR THE ATLAS SEMICONDUCTING TRACKER UPGRADE:

CERN SINGLE MODULE SYSTEM

ADRYANNA SMITHBAYLOR UNIVERSITY

DUKE/TUNL REU 2015

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OUTLINE• Purpose for traveling to

CERN

• Tasks at the lab

• Single module tests

• ttbarV analysis

Saint Genis-Pouilly, France

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WHY WE WERE SENT TO CERN• CERN experiments demand enormous collaborations

• Characterizations and documentation of detector components, performed by many institutions

• Duke is a primary source of manpower for SCT upgrade

• Knowledge gained at Duke -> Knowledge helping with CERN setup -> Knowledge for future Duke setup

Atlas Detector Controls

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THE ASSIGNMENT

• Relocation of electronics and DAQ system to new building

• Re-commissioning of the new location

• Lots of wires• Lots of power

supplies• Lots of boards• Lots of

troubleshooting

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THE NEW LOCATION

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THE SINGLE MODULE

Stream 1Stream 0

Stream 0Stream 1

Hybrid 0

Hybrid 1

One Module

Power Supplies and Interlock

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TESTS • iDelay, Strobe Delay, Trim Range,

3 Point Gain, etc.

• 3 Point Gain

• Send in 3 levels of charge pulse: 0.52, 1.00, 1.48 fC

• Pulse comes in… hit registers in a % of channels, depending on the threshold

• Variance in threshold distribution “Noise” reading

Occupancy vs. Threshold

V50

8*Result: Higher temperature -> higher noise

9*Result: Higher HV bias -> lower noise, to an extent

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FUTURE OF THE UPGRADE @ CERN• Will likely move stations again within SR1

• CO2 lines for cooling stavelets

• Atlys board will replace HSIO board

• Connect stavelets and run tests

• Document the setup and test results

• Other institutions (such as Duke) can replicate our work• Nascent Twiki page

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V ANALYSISttbar

V = Vector Boson (Spin 1, force carrier)

• Duke graduate student Chen Zhou’s analysis: Same Sign Dilepton Decays• Interested in looking at Triplepton (3L) Decays using AIDA technique

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A CLOSER LOOK• Uses √s = 8 TeV data from ATLAS detector

• These cross sections investigate top-EW coupling

• ttbarZ is particularly interesting

• Similar to ttbarH decay channel• Studying cross section of Higgs interactions is hot topic

• 2 Major Trilepton Regions:

• Make further cuts based on ET, isolation (tight/loose), and jets

3L-Z3L-noZ

e-e+ μ- μ+the lepton options

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ANALYSIS UPDATE• Lots of code to decipher

• Lots of terms to decipher

• SCT upgrade work, background reading, and lectures kept us engaged

• Beginning to make progress… but in the end, the summer ran out

ssh -Y adsmith@lxplus.cern.ch

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ACKNOWLEDGEMENTS

Thanks goes to Mark Kruse and Ayana Arce for acting as our advisors. A keen gratitude also towards Chen Zhou for his mentorship at CERN. And of course, the other undergrads, Chloe Lindeman, Bolaji Eniwaye, Shelby Burant, and Matt Tobin!

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SOURCES• Carlos Garcia Argos (2012), Valencia University

• Procedure for Operating the HSIO DAQ System for Single Modules in the B180 Setup

• Chen Zhou, et al. (2015), ATLAS Paper

• Measurement of the ttbarW and ttbarZ production cross sections in pp collisions at √s = 8 TeV with the ATLAS detector

• Chen Zhou (2015), ATLAS AIDA Group Poster

• Measurements of the ttbarW/Z production cross sections using events with same-sign leptons from pp collisions at √s = 8 TeV with the ATLAS detector

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DEEP BURNING QUESTIONS??• You may now ask me and Chloe questions

• FAQ

• When did you both first learn that you were spectacular?• From a young age.

• Is physics good for anything?• It’s not bad for anything and its study has yet to be linked

to cancer (radiation), obesity (#desklife), or deforestation (problem sets).

• How can CP Violation be resolved?• Use a small enough wavelength and you can resolve

almost anything.

• Where is CERN?• In an expensive land, far, far away from Taco Bell.