Heather Russell
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Heather Russell

Experimental Particle Physicist

Geneva, CH

hrussell AT cern.ch


ATLAS Software (athena)









Ongoing Research

I currently work on the ATLAS experiment, and am involved in two distinct analyses, both of which have the goal of carefully measuring rare Standard Model processes.

  • Standard Model multi-boson measurements:
    • I am leading a precision measurement of events with W boson and two photons. Although it is predicted by the Standard Model, this final state has not been observed before.
    • In addition to coordinating the analysis effort, I supervise two PhD students from McGill University whose theses will comprise this analysis.
    Lepton flavour universality in B-decays:
    • I am participating in the first effort on ATLAS to measure lepton flavour violation in B-meson decays through the measurement of the ratios of rare state decays to electrons and muons.
    • My efforts have been focused on the development of a trigger for the electron channels and retuning of the electron identification algorithms to correctly identify electrons that are close-by or from a secondary vertex.

PhD Research

I worked on searches for hadronically-decaying long-lived, neutral particles in ATLAS, with a focus on the reconstruction of decays in the muon spectrometer. My main contributions were as follows:

  • Analysis contact for Run-2 searches for displaced hadronic jets searches:
    • Contact for a group of analyses covering the reconstruction of decays in the inner detector, hadronic calorimeter, and muon spectrometer.
    • Organise weekly analysis meetings.
    • Ensure compliance with the latest recommendations from detector and physics performance groups.
  • Custom triggers for long-lived particles:
    • Maintain and improve Run-2 triggers for displaced decays.
    • Determine systematic uncertainties and scale factors due to mismodeling in monte carlo (MC) simulation
  • Identification and reconstruction of muon spectrometer decays:
    • Studied 13 TeV muon spectrometer vertex reconstruction performance
    • Performed data -- MC comparisons for systematic uncertainties.
    • Created a monitoring tool to study each step of vertex formation
    • Made improvements to seed criteria in for track formation, which boosted performance timing and algorithm robustness.
  • Creation and maintenance of analysis software using the RootCore framework

Phenomenology work

Data-driven Model-independent Searches for Long-lived Particles

One of the interests I have developed over my time on ATLAS is in designing searches to be optimally recast able by the theory community. To this end, I worked with two theorists and two experimentalists on a paper outlining a method for model-independent searches for long-lived particles. This approach allows us to perform a coarse, topology-based search, covering a much larger area of phase space than the currently published analysis.

A. Coccaro, D. Curtin, H. J. Lubatti, H. Russell, and J. Shelton, Phys. Rev. D94, 113003 (2016), arXiv:1605.02742 [hep-ph].

ATLAS work

B-physics and Light States trigger coordination (Oct 2017 - present)

I am currently the coordinator of the B-physics and Light states trigger group, managing a team of around ten physicists to ensure the optimal performance of triggers selecting B-meson (and other light state) candidates. This has involved close collaboration with both the physics analyses within the B-physics and Light States Working Group and the trigger community. During my tenure as coordinator, I have:

  • Developed triggers targeting new final states that ATLAS has previously not been able to study
  • Optimised the data-taking strategy to ensure that we are recording as many B-physics events as possible, within the various rate and bandwidth limitations
  • Supervised of students working on qualification tasks
  • Maintained the B-physics trigger code.

Trigger menu work (Jan 2017 - present)

I work in a small team of experts to ensure that the ATLAS Trigger Menu is ready for data-taking and Monte Carlo campaigns. This task involves:

  • Careful implementation and validation of new triggers for physics analyses, performance, data quality, and detector monitoring
  • Development and maintenance of monitoring tools used in trigger operations
  • Week-long expert on-call shifts

Data preparation (2016 - 2017)

  • Co-coordinate the selection and processing of raw events into a specialised data stream.
  • Developed a set of tools for monitoring the rate of each individual component of this data stream.

Muon data quality (2013 - 2016)

I was responsible for offline data quality monitoring for the Monitored Drift Tube (MDT) chambers. This involved:

  • Updating and maintaining the existing software.
  • Investigating of a new type of noise identified by the monitoring software during cosmic runs in summer 2015.
  • Developing new monitoring to quickly characterise noise in future data taking.
  • Supervising two PhD students at CERN during summer 2015, one in developing a method for baseline noise calculation in MDTs, and the other in developing and improving the offline MDT data quality software.
  • Taking shifts both as an offline muon data quality expert and shifter.


Supervision of graduate students (McGill University)

I currently supervise two PhD students within the context of our Wγγ measurement. I also supervised another PhD student on their qualification task within the BLS trigger group. Additionally, I supervised a Master's student who did a cross-section measurement and spin determination of the Z boson.

Teaching Assistant (University of Washington)

September 2011 - June 2013

Each quarter I was assigned as a teaching assistant for 2 - 3 undergraduate classes. Duties ranged from grading problem sets and lab reports to leading lab or tutorial sessions. From April - June 2013 I served as the primary TA for a particle physics course, where I held weekly office hours, generally helping 10-20 students with questions about the week's lectures. Additionally, based on my experiences assisting students throughout the quarter, I developed a tutorial on the more difficult topics for exam preparation. For the 2012 academic year, I was the graduate student representative on the undergraduate introductory physics committee. We reviewed and discussed exam questions, grading rubrics, course structure, and textbook choices. In summer 2012, I was an instructor for the NSF Summer Institute in Physics and Physical Science for Inservice K-12 Teachers. This is a program designed to enhance teachers' reasoning and understanding of physics. The teachers worked in small groups of 3-4 on inquiry-oriented modules, and as an instructor I was present to assist them with gaps in understanding without simply providing the answer.

Intern (Dwight International School)

September 2009 - August 2010

I provided one-on-one tutoring during the day for all students, during their free periods, in math and science, and I would substitute teach for teachers who had to leave on short notice. Four evenings a week, the boarding students had a mandatory study hall that I was present at to help the students with their homework. I also assisted teachers in-class with science experiments, test supervision, and technical support in the computer lab.

Employment History

Research Associate, McGill University
Jan 2017 - Current


U.S. ATLAS Outstanding Graduate Student Award

For exceptional contributions to the ATLAS experiment

Henderson Prize (Department of Physics, University of Washington)

For an outstanding Ph.D. thesis


University of Washington
2011 - 2016

PhD in Physics

Thesis: Search for long-lived particles decaying in the muon spectrometer of the ATLAS detector at the LHC

(description in research section)

Perimeter Institute
2010 - 2011

MSc in Theoretical Physics

Project: An exploration of the force structure and surface tension of DOPC lipid bilayers

I worked with the Nanoscale Biophysics Group at the University of Waterloo, where I developed a theoretical model for the force structure and surface tension of phospholipid molecules in cell membranes, complementing the experiments performed by the group.

University of Victoria

2005 - 2009
BSc Honours Physics (With Distinction)

Thesis: Sound source localization with microphone arrays using a linear closed-form algorithm

I developed a program that used recorded sound data from five microphones placed in a known, non-singular three-dimensional configuration and calculated the position of the sound source using time delays between the sound recorded from each of the microphones. During the course of the four-month project, I tested the ability of numerous microphone configurations to accurately locate speakers through which news radio was played.