9:00 a.m. - 10:15 a.m. PST	Microwave and Optical Atomic Clocks: Past, Present, and Future	Dr. Shimon Kolkowitz
10:30 a.m. - 11:45 a.m. PST	TAI, UTC, and UTC(k): The Role of the Time Laboratories in the Realization of Reference Time Scales	Dr. Jeff Sherman
11:45 a.m. - 12:45 p.m. Buffet luncheon for tutorial attendees
12:45 p.m. - 2:00 p.m. PST	Introduction to Timescales	Dr. Demetrios Matsakis
2:15 p.m. - 3:30 p.m. PST	White Rabbit: Technology, Applications and Best Practices in Disseminating Traceable Reference Time Scales	Javier Serrano
3:45 p.m. - 5:00 p.m. PST	Low-Noise Digital Electronics for Time and Frequency Metrology	Dr. Claudio Eligio Calosso

Microwave and Optical Atomic Clocks: Past, Present, and Future

Time: Monday, January 27, 9:00 a.m. - 10:15 a.m.
Room: Beacon A (4th floor)

This tutorial includes a summary of the history of atomic clocks and their applications. It will start with the motivation, development, and operating principles of microwave atomic clocks, and will discuss their impact on physics research and society. It will provide a brief overview of some of the important figures of merit for atomic clocks, such as systematic accuracy, fractional frequency instability, reproducibility, and Allan deviation. Optical atomic clocks will be introduced, and the operating principles of both trapped ion optical clocks and optical lattice clocks will be explained. Emerging applications of optical atomic clocks, such as searches for new physics, gravitational wave detection, and relativistic geodesy will be explained. This section will conclude with looking to the future of where atomic clock research may be headed.

Dr. Shimon Kolkowitz is a professor of physics at UC Berkeley; and an experimental atomic physicist and quantum scientist, with his research focusing on precision measurement, quantum sensing, and metrology.

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TAI, UTC, and UTC(k): The Role of the Time Laboratories in the Realization of Reference Time Scales

Time: Monday, January 27, 10:30 a.m. - 11:45 a.m.
Room: Beacon A (4th floor)

Coordinated Universal Time (UTC) is, by far, the most widely adopted consensus time scale for legal, commercial, metrological, and technical purposes. This tutorial discusses the methods and roles of national metrological laboratories in the realization and dissemination of UTC. We will also highlight some current challenges and opportunities: growing demand for accurate time distribution without dependence on global navigation satellite systems (GNSS) or without the complications that so-called leap seconds bring to digital time scale systems, and the campaign to redefine the SI second in terms of an optical atomic transition frequency.

Dr. Jeff Sherman currently leads the Time Realization and Distribution Group at the National Institute of Standards and Technology (NIST). Jeff’s research centered around high-precision measurements in optical-atomic systems. He holds a PhD in Physics from the University of Washington, with postdoctoral work at the University of Oxford, and a National Research Council associateship at NIST.

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11:45 a.m. - 12:45 p.m. Buffet luncheon for tutorial attendees

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Introduction to Timescales

Time: Monday, January 27, 12:45 p.m. - 2:00 p.m.
Room: Beacon A (4th floor)

Dr. Demetrios Matsakis recently retired from Chief Scientist for Time Services at the U.S. Naval Observatory (USNO). In his 40 years at the USNO he worked on most aspects of precise timekeeping. Dr. Matsakis has published more than 160 scientific papers, and is ex-president of the International Astronomical Union's Commission on Time. He is currently Chief Scientist for Masterclock, Inc.

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White Rabbit: Technology, Applications and Best Practices in Disseminating Traceable Reference Time Scales

Time: Monday, January 27, 2:15 p.m. - 3:30 p.m.
Room: Beacon A (4th floor)

This tutorial will cover the working principles of White Rabbit (WR) technology, starting with a detailed description of the fundamental building blocks of any WR network: the WR switch and the WR PTP Core. We will also discuss calibration of delays and asymmetries in a WR link. After a brief detour about the WR community and ecosystem, we will move on to describe some applications of WR in domains as diverse as physics, finance (including regulatory and traceability aspects) and future quantum networking technology. Finally, we will focus on one particular application, long-distance time transfer, and describe a set of best practices to optimize the performance of such links, as well as ongoing work to improve WR performance in this type of application.

Javier Serrano leads the Electronics Design and Low-level software section in CERN’s accelerator Controls, Electronics and Mechatronics group.

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Low-Noise Digital Electronics for Time and Frequency Metrology

Time: Monday, January 27, 3:45 p.m. - 5:00 p.m.
Room: Beacon A (4th floor)

This tutorial focuses on the role of electronics in time and frequency metrology. It shows why a proper design of the electronic apparatus is a key aspect of an application: a new experiment, instrument or facility. After a brief comparison of off-the-shelf commercial versus custom solutions, the tutorial will show how to develop a custom high-performance and flexible apparatus. High performance is provided by low noise components, while flexibility is guaranteed by digital devices, in particular by Field Programmable Gate Arrays (FPGAs). Practical examples among vapor cell clocks, coherent fiber links and timescale generation in real-time are then provided for clarifying the advantages of this approach.

Dr. Claudio Eligio Calosso is an INRIM senior researcher using low-noise digital electronics for innovating time and frequency metrology. His activities include primary frequency standards, vapor cells clocks, frequency dissemination over fiber links, phasemeters, frequency division and synthesis and, recently, real-time time scale generation. He is also interested in signal analysis, with particular attention to the role of aliasing in time interval counters and two-sample variances.

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