Helen (Eleni) Petrakou

short note    cv    profiles

Short note

My training and expertise are on experimental particle physics, with some emphasis on data analysis. I recently worked on astrophysics and currently look for expanding my research activities.

Following a degree in physics, interspersed with some programming work, I entered the graduate program on elementary particles under scholarship by the Greek National Research Center "Demokritos". After a dissertation on supersymmetric phenomenology I joined the local group of CERN's CMS experiment for my PhD.

During the PhD and the subsequent fellow position with the National Taiwan University (NTU) I was a member of the CMS collaboration. I participated in searches for new physics (anomalous gauge couplings and vector bosons), operations of the electromagnetic calorimeter, and electromagnetic particles reconstruction.

I partially moved to "tabletop" experiments when joining the Center for Axion and Precision Physics Research (CAPP) in S. Korea, a group dedicated to exploring the strong CP problem through nucleon electric moments and the Peccei-Quinn axion particle.

During the preparation phase of axion haloscopes I worked on RF cavities, cryogenic operations and quantum noise. In addition I participated in the simulation of future accelerator-based proton EDM measurements.

In the last year I worked without affiliation on a model of the solar cycle evolution. The study was recently published.

Research experience

2017: Freelance researcher

Project in solar physics

  • "A deterministic model for forecasting long-term solar activity" (Journal of Atmospheric and Solar-Terrestrial Physics, Vol. 175, 18 2018, link; previous version on arXiv)
  • "A deterministic model for forecasting long-term solar activity" (presentation at the Asia-Pacific Regional IAU Meeting)

2015-2017: Research fellow at the Center for Axion and Precision Physics Research (CAPP, Institute for Basic Science, S.Korea)

Axion haloscope experiments

Polarimetry for proton electric dipole moment measurements


  • "Haloscope searches for dark matter axions at the Center for Axion and Precision Physics Research" (proceedings of the ICFNP 2016 conference; link)
  • "Noise calculation for the detection of cavity axions: Linear amplifiers and single-photon techniques" (internal CAPP Note)
  • "A Storage Ring Experiment to Detect a Proton Electric Dipole Moment" V.Anastassopoulos et al. (Review of Scientific Instruments, Vol. 87, 11 2016; link)

2006-2014: Member of the Compact Muon Solenoid experiment (LHC/CMS, CERN)

Physics beyond the Standard Model

Electromagnetic calorimetry

Data analysis, machine learning

Selected publications:

  • "Combined Measurement of the Higgs Boson Mass in pp Collisions at \sqrt(s)=7 and 8 TeV with the ATLAS and CMS Experiments" (Phys. Rev. Lett. 114, 191803 2015)
  • "Search for pair-produced vectorlike B quarks in proton-proton collisions at \sqrt(s)=8TeV" (Phys.Rev. D93, 11 2016)
  • "Energy calibration and resolution of the CMS Electromagnetic Calorimeter in pp collisions at \sqrt(s)=7 TeV" (JINST 8, P09009 2013)
  • "Observation of W\gamma and Z\gamma production at \sqrt(s) = 7 TeV" (Phys.Lett.B701, 535-555 2011)
  • "Commissioning of the Particle-flow event reconstruction with the first LHC collisions recorded in the CMS detector" (CMS Physics Analysis Summary PFT-10-001 2010)

2011-2014: Research fellow at the National Taiwan University

- Reconstruction and analysis software for the ECAL/Preshower detector (contact person).
- Searches for vectorlike quarks.
- Electron/photon reconstruction + contact to the heavy quarks group.

2006-2010: PhD at the Institute of Nuclear Physics, Greek National Research Center "Demokritos"

- Thesis on "The Search for anomalous trilinear gauge couplings in the Z\gamma channel at the CMS/LHC experiment".

Other posts:

Oct 2008-Feb 2009: Software developer, CERN

- Data Quality Monitoring during assembly operations of the ECAL/Preshower subsystem (CMS experiment).

1999-2000: Software developer, Dep. of Mechanical Engineering, Patras Technical University, Greece

- Development for virtual reality applications for engineering prototyping and training (Laboratory of Manufacturing Systems).


2017-8 chapette.net