Mentoring CMS postdocs at Fermilab

At Fermilab we mentor postdocs to become full-fledged scientists, supporting both the scientific development and the career advancement of postdocs so they can lead our field into the future.

The postdoc mentoring program in the CMS Department has served as a model for similar programs throughout the lab. It relies on three basic elements to guide the postdoc to success: a balanced and ambitious research plan, a personal team of supporting scientists, and regularly scheduled mentoring events.

A light-hearted moment at the CMS postdoc meeting, where Fermilab postdocs present their research strategy to the CMS department. Photo: Gabriele Benelli

It is sometimes said that “plans are useless, but planning is indispensable.” This is especially true in science, where what we learn from our research informs our future direction, but our research should be both ambitious and achievable. When a postdoc joins the CMS Department at Fermilab, they are asked to choose research topics in physics and technology and encouraged to select the ones that they are passionately driven to explore. For their first month at Fermilab, the postdoc’s only assignment is talking to scientists and other postdocs in the CMS Department, learning about ongoing research, and developing their own research plan.

Postdocs distinguish themselves in physics research by leading the most interesting explorations of the interactions of elementary particles. Each one has a chance to develop and lead a unique physics analysis, and there are plenty of possibilities at CMS, since there are hundreds of potential processes in proton-proton collisions. Fermilab postdocs on the CMS experiment have played leading roles in the discovery of the Higgs boson. They have measured the fundamental properties of the Higgs and the top quark, the most massive quark because of its strong attraction to the Higgs, and have measured the Higgs decays into bottom quarks. They have looked high and low for supersymmetry and have hunted for dark matter, the unseen particle making up a quarter of the universe. They have developed the techniques that allow CMS to search for new particles moving at high velocity, so-called boosted searches, where the decay products of the new particle are on top of each other and hard to separate in the detector. They have published searches for exotic models of new physics inspired by the most ambitious ideas trying to explain our universe, like grand unification of all forces, a quantum theory of gravity, extra dimensions of space-time, quark and lepton compositeness, and many others.

Fermilab postdocs Ryan Heller, left, and Cristian Pena work on prototypes of the MIP timing detector for HL-LHC. Photos: Artur Apresyan

Postdocs distinguish themselves in technical research in projects focused on cutting-edge experimental technology. CMS Department scientists work with postdocs on the world’s most advanced detection, trigger and computing systems. During the past 15 years, 36 former Fermilab postdocs on CMS have primarily led the continuous development, commissioning and operations of the trackers, muon detector, hadron calorimeter, data acquisition, triggering and computing. CMS is currently working on a new upgrade to the detector to handle the increased luminosity planned for 2027 — the High-Luminosity LHC. Currently, 13 CMS postdocs lead in the development of new systems for High-Luminosity LHC, specializing in the high-granularity calorimeter, outer tracker, MIP timing detector, trigger, computing and machine learning. The 49 current and former CMS postdocs have diverse international origins, and 11 of them are women.

Fermilab postdocs teach at the CMS Data Analysis School. Nick Smith describes a problem (left), Fabio Ravera views progress (middle), and Karri DiPetrillo points out a solution (right). Photos: Marguerite Tonjes

The LHC Physics Center at Fermilab is also an important part of mentoring. It provides a research environment in which physicists throughout CMS share ideas, collaborate and obtain recognition.  The postdocs hone their physics, organizational and communication skills by both participating in and organizing LPC events such as workshops, weekly seminars, physics forums and hands-on tutorials. Once per year they spend an intense week running exercises at the CMS Data Analysis School, good teaching experience preparing them to be professors. LPC provides the recognition and support of being LPC distinguished researchers to postdocs with the most compelling research plans, an honor achieved by 18 Fermilab postdocs so far.

In the first month, while postdocs are choosing their research topic, they are also choosing scientists who will serve in the critical roles of supervisor, mentor, and analysis and technical research guides. It may seem crazy, but in this case Fermilab allows employees to choose both their work and their bosses! They are often best supported by colleagues they choose, with whom they share common interests and mutual respect. Each postdoc’s team of up to four scientists ensure that the postdoc’s research plan is excellent. More important, this team provides ongoing one-on-one support and advice to help the postdoc attain the research accomplishments and professional recognition necessary to obtain a permanent scientific position.

Fermilab postdoc Maral Alyari presents her research on the high-granularity calorimeter to the CMS Department at a recent postdoc meeting. Photo: Gabriele Benelli

A plan and a mentoring team are not enough; we find “it takes a village” to mentor a postdoc.  Monthly postdoc meetings of the CMS Department at Fermilab provide a forum for developing excellence in both research and communication. Postdocs also practice their conference presentations and research seminars in front of an audience of scientists, and receive suggestions to improve their talks. In quarterly meetings, a mentoring committee provides advice to the postdoc’s supporting scientific team, and the team reports on his or her progress to the mentoring committee. Annual meetings on performance evaluation include the postdoc, the postdoc’s team, and CMS management at Fermilab. These meetings also focus on visibility and recognition of the postdoc’s accomplishments, conferences, publications and developing the relationships needed for strong references. When it comes time to apply for permanent positions, the postdoc’s team and the mentoring committee review and advise on the postdoc’s list of references, cover letter, curriculum vitae, and research and teaching statements.

Current and former (f) Fermilab postdocs on CMS stand with the founder of the mentoring program (m). Back row, from left: Kevin Pedro (f), Matteo Cremonesi, Christian Herwig, Nicholas Smith, Thomas Klijnsma, Robert Harris (m). Front row, from left: Ryan Heller, Fabio Ravera, Allison Reinsvold Hall, Karri DiPetrillo, Maral Alyari, Hansjoerg Weber and Nhan Tran (f). Photo: Gabriele Benelli

At Fermilab we mentor our postdocs to help them succeed, not only in practicing science now, but also in their scientific careers in the future. I founded the postdoc mentoring program at CMS and developed its guidelines in close collaboration with Fermilab senior scientist Daniel Elvira. Postdoc mentoring committee members continually improve and update the program, which is designed to help postdocs who aspire to become professors at research universities and scientists at physics laboratories around the world. From the CMS Department at Fermilab, roughly 60% of former postdocs now have tenure-track or permanent positions within high-energy physics. This is more than typical, as roughly 20% of postdoctoral researchers in physics get tenure-track academic positions in the United States. Some Fermilab postdocs, like Caterina Vernieri, received multiple offers for scientific positions.

Clearly, much of the program’s success is because Fermilab’s scientific opportunities attract the world’s most talented researchers. Nevertheless, like all of us, sometimes even brilliant postdocs just need a “little help from their friends” to succeed, and that is what Fermilab postdoc mentoring tries to provide.

Robert Harris is a Fermilab scientist on the CMS experiment.

CMS Department communications are coordinated by Fermilab scientist Pushpa Bhat.

Former Fermilab postdoc Caterina Vernieri, now a Panofsky fellow at SLAC, stands in front of the CMS tracking system at CERN. Photo courtesy of Caterina Vernieri