Overview:
- Summer School Participant Group Photo at CENAM
The BIPM-SIM UTC Summer School was held from May 7-9, 2025, at CENAM in Queretaro, Mexico, to address several regional challenges in time and frequency metrology by providing intensive training to expand workforce capabilities. The school targeted participants at different experience levels who were fulfilling technical time and frequency roles related to UTC and timekeeping, with a focus on SIM member institutions. Through hands-on sessions and expert-led tutorials, the school supported capacity building in labs facing resource constraints by offering practical knowledge in areas like UTC basics, GNSS receiver calibration, time scale implementation, and time and frequency analysis techniques.
Learning was addressed through an equal mix of tutorial presentations, hands-on demonstration of BIPM-CBKT developed web-based analysis tools, laboratory demonstrations of GNSS receiver operation and calibration, and timescale steering. Additionally, a tutorial on emerging optical technologies related to timekeeping was included to introduce participants to metrology developments and advancements effort to support the second redefinition of optical atomic standards.
The technical sessions were complemented by unstructured and structured networking activities that were held inside and outside school hours. The structure was designed to ensure that participants acquired the necessary skills and background in the experimental work and data coordination required for maintaining a national timescale that is traceable to UTC. Most importantly, by fostering peer exchange and highlighting successful regional practices by local instructors and participants, the school helped participants engage with peers within the SIM network. Sessions also addressed application awareness, guiding participants on how time metrology connects to national priorities, while discussions around time service distribution offered insight into enhancing reliability.
School information and statistics:
The funding was provided from the UFFC-S program, and it was allocated to SIM to support participant travel to the BIPM-SIM UTC Summer School. This funding supported a total of 16 participants, including 3 instructors. Please note that a separate financial report will be generated by the SIM secretariat, which was responsible for providing travel reimbursement to school participants, and support to CENAM regarding local transportation, and other logistical services (lanyards, coffee breaks, lunch breaks, and networking events, etc).
The school had a total of 34 participants, including students, instructors and invited speakers from the following 18 nations: Bolivia, Mexico, Canada, Brazil, Guyana, Columbia, Trinidad and Tobago, Jamaica, Guatemala, Bahamas, Cost Rica, Peru, Argentina, Panama, Uruguay, India, United States, and France.
Of the participants, most were from labs currently participating in UTC. Three participants were from labs planning to contribute to UTC within the near future (2-3 years). One participant was from a laboratory that did not contribute to and was not planning to contribute to UTC in the near term. However, their associated laboratory was a member of NIST SIM time (SIM Time and Frequency Working Group), which was notable, as experts from NIST were at the school presenting the newest version of their NIST SIM time receivers (TMAS), which will be distributed to SIM labs in the coming months. The new system will provide an upgrade to the current technology and will support the BIPM’s standard clock data format, enabling labs to use the receivers to contribute to TAI.
Final Summer School Technical Program:
Assessment methods:
A preliminary survey was distributed to the SIM community to gather feedback on the technical content and training needs before the summer school.
Survey on Laboratory Capabilities
A second survey was sent to confirmed participants to assess the technical capabilities of their laboratories. It requested details on available equipment and infrastructure, allowing instructors to tailor content to participants’ contexts and to better understand the diversity of laboratory capabilities across the region.
• This survey was deployed after the participant list was finalized and before the start of the School.
Post-Event Survey
The post-event survey aimed to evaluate participants’ learning outcomes, as well as the accessibility and effectiveness of different learning experiences, including tutorials, hands-on sessions, networking, and laboratory demonstrations.
• It also collected information on participants’ expertise and technical needs to support the development of peer mentorships across SIM RMOs.
• The survey was administered on the final day of the event to maximize response rates.
Breakdown by participant experience level:
A SIM preliminary survey was used to assess topical interest:
Summary of Participant Feedback from the SIM Summer School:
Overall Experience and Reflections
- Ricardo Gutierrez from CENAM is demonstrating aspects of how to calibrate a GNSS receiver as part of a live laboratory equipment demonstration.
Feedback about the summer school was overwhelmingly positive. Participants described the event as enriching, well-organized, and valuable for both learning and networking. Many noted that the experience expanded their understanding of time and frequency metrology and helped them build relationships with colleagues from other National Metrology Institutes (NMIs). Attendees praised the opportunity to engage directly with experts and organizers and felt inspired to apply their learning locally. Some suggested extending the duration of the school to allow for deeper engagement.
The average student rating for the school was a 4.7 out of a maximum of 5. The lowest feedback received was for the live laboratory demonstrations (3.9 out of 5), because participants were not able to repeat the experiments themselves. As a result of the feedback, we are planning to allow to make this possible for the next UTC summer school at the BIPM.
Participants’ Favorite Aspects of the School
3. School networking and dinner event
The most valued element of the school was networking, both formal and informal. Participants highlighted interactions during lunch, breaks, van rides, and evening events as critical for fostering collaboration and sharing knowledge. Structured formats such as “subject tables” and shared lab detail sessions were also praised. Others appreciated the technical content, particularly hands-on sessions and software tools that complemented theoretical presentations.
- We will use this feedback to look for opportunities to expand networking sessions for the upcoming BIPM UTC Summer School in September 2025.
- Regarding networking, feedback from our participant survey emphasized the importance of expanding digital tools for connection and enhancing hands-on learning opportunities. Participants recommended recurring, flexible, and structured formats tailored to varying levels of experience and institutional capacity.
Future Support Requested from SIM, BIPM, and CENAM
Participants expressed a desire for:
- More virtual training and local expert support
- Help prepare strategy plans, evaluate equipment, and acquire national lab infrastructure (e.g., rubidium or cesium clocks)
- Easier access to specific experts, technical resources, and tutorials
- Guidance on how to advocate nationally for investment in time and frequency capabilities
- An official mechanism to participate in SIM activities, especially for those outside national NMI structures
- Improved connectivity and access to digital resources
Desired Future Activities from the SIM Community
Participants would like to see:
- More regional summer schools and follow-ups from experienced metrologists
- Increased focus on knowledge sharing and collaboration
- More GNSS calibration initiatives
- Creation of a cloud-based resource hub
- An NMI training school for early-career professionals
- Continued review and improvement of laboratory processes
- Opportunities to share technical experiences and services
4. Carlos Ortiz Cardona giving a lab tour of CENAM’s microwave timescale.
Conclusion:
The SIM Summer School successfully met its goals of fostering learning and community building. However, there is clear enthusiasm for deeper engagement, more practical training, and stronger support for capacity building across the region. The feedback offers a roadmap for more inclusive, effective, and collaborative regional development in time and frequency metrology.
Follow up events:
- The BIPM UTC Summer School is coming up September 9-11, 2025, at the BIPM, in Sevres, France. This school will assume a similar structure, but will build on feedback received regarding the SIM Summer School.
- Two CCTF Technical exchanges are coming up on June 25th and July 9th, which will highlight the work of previous secondees Bharath Vattikonda and Yuko Hanado on the tools and courses they developed around the topics in UTC. These technical exchanges will discuss standardized data formats, data verification, as well as the more complex topic of timescale averaging. These events are listed here: CCTF Working Group on TAI (CCTF-WGTAI) – BIPM
- UTC-related courses developed by previous secondees can be found here: https://e-learning.bipm.org/local/explore/index.php?field%5B0%5D=provider&value%5B0%5D=0&field%5B1%5D=ta&value%5B1%5D=12&sort=popularity
- The above are free courses, open for registration to any interested party. The e-learning courses cover topics including video recordings of previous CCTF technical exchanges, shared time and frequency community resources, as well as courses pertaining to data analysis, BIPM standard clock data formats, data validation, and more!
- The BIPM is beginning conversations with members from AFRIMETS interested in developing more awareness about interests, opportunities, and challenges around contribution to UTC.
Special Thanks:
Colleen Brick, Holly Lay, and Arianna Rohrer for their invaluable assistance in navigating the agreement logistics. We are also deeply grateful to Claudia Santo, the SIM Secretariat, for her tireless efforts in assisting participants with flight arrangements, visa processing, hotel coordination, and reimbursements.
Additional thanks go to Yenna Yockim and Mauricio Lopez (CENAM), Johanne Flament and Chingis Kuanbayev (BIPM) for their support in advertising and coordinating the event through the EFTF/IFCS and BIPM channels. We also thank Claudia Santo and Diego Luna (INTI) for their help in deploying and managing participant surveys.
Finally, we extend our heartfelt thanks to Carlos Ortiz Cardona and the dedicated staff and scientists at CENAM for their outstanding work in managing on-site setup and logistics throughout the event.
Prepared by Dr. Tara Fortier (NIST Physicist and BIMP Capacity Building Coordinator)
Preparation date: May 27, 2025
