CMS WZH-path measurement 2024

This page is to help to guide mentors and teachers in planning the masterclass with the CMS WZH-path measurement..


Need more prep? Try our Instructional Screencasts!



First things: iSPy and spreadsheets

Each computer should have robust internet access (preferred) or the DVD version of the masterclass loaded. Two students should work together at each computer to complete 100 events of the 10 000-event sample.


  • Students must have access to the event display program iSpy-webgl using the latest version of Chrome, Edge, Firefox, or Safari.
  • Students must have access to the online spreadsheet. These will be linked from the schedule of CMS videoconferences under Data Analysis below.
  • Students should have access to the CMS Masterclass website prior to the masterclass day.

Download versions:

See documentation, below.


Grab the data:

See Data Analysis, below.


Familiarize yourself:

Please note that introduction of the new CIMA data tool means key procedures have changed. It is important for mentors to and teachers review the documentation and try it out in the CIMA Sandbox.

Share these with students when appropriate!



Students arrive

This should occupy the first 30-60 min

  • Registration: please have students sign in on a registration sheet with name, school, and teacher.
  • Gateway experience: have a cloud chamber, e/m apparatus, or something similar to whet interest
  • Ice-breaker activity: students in small heterogeneous groups create 1-2 good questions about particle physics, ATLAS, and/or LHC.



Shift training

Get students ready for their data analysis shift! This will take about 3 hours, though parts of it can be moved to other times of the day.

Mentor presentation, 30-60 min:

  • keep it interactive - ask questions about prior experience, shows of hands, wild guesses, etc.
  • give students something to touch, e.g. a wave-shifting fiber
  • connect to classroom prep
  • touch on standard model
  • talk about your research
  • template

Tour, 30-60 min:

  • adds much to the day - often most popular part
  • if you have an accelerator to show, great!
  • if not: any interesting labs, even if not particle physics, are still great
  • have enthusiastic grad students around to chat and explain

Analysis Prep (30-60 min):

  • Have a teacher lead this if practical.
  • Use/adapt the data analysis slides (PPT) (PDF).
  • Important: go through "masterclass-samples" in iSpy-online on the projector with the students:
    • Show students how to navigate to a data file
    • Discuss how to use the tools in iSpy-online (or iSpy-dvd)
    • Discuss each event in terms of:
      • Particle tracks, missing energy, ECal deposits, etc.
      • Most likely parent particle (ask them what is what)
    • Show how to record results on sample spreadsheet.

Lunch with a Physicist (30-60 min):

  • This is also very popular and a great way for students to interact and get comfortable with scientists.



Data Analysis

This is the heart of the masterclass and takes 60-90 min. There should be 2 students at each computer, cooperating to get their data measured. Mentors, tutors, and teachers should circulate to help the students analyze the events and work out any problems they have. Don't give them answers. Help them figure things out and learn to see data as scientist does. Remind them that each event is a candidate Z, W, Higgs, or something else - not a definitively identified particle.

Note: Google spreadsheets have been phased out in favor of CIMA. If there are special cicumstances, contact Ken Cecire for an exception.




Sharing Results

This takes a little over one hour. Both parts are important.

Discussion (30-45 min):

  • Mentor leads, students interact
  • Look at combined mass plots for your institute in spreadsheet.
  • Help students point out peaks, bumps, significance; discuss results.
  • Each institute is assigned another institute to question: look at their data as well. Students should form questions and comments.

Videoconference (30-45 min):

Connecting to videoconferences:

Course of a videoconference:

  • Connect to videoconference link or Indico page (see above).
  • Someone should log into the videoconference 15 min early to be sure the connection is established. See the Schedules page.
  • Follow the agenda on Indico:
    • Introductions and warm-up
    • Institute results
    • Combined results
    • Discussion, Q&A, and wrap-up
  • It is good to have a student spokesperson but try to arrange so it is not too hard for another student to make a comment or ask a question.

After this, we have post-discussion and closeout.

Before you go home:

Please report your attendance numbers on our Attendance Form!


Have a great day!