Nobumichi Tamura thought he’d received the wrong email. After submitting a nomination for someone else, he was surprised that the Advanced Light Source (ALS) Users’ Executive Committee (UEC) had selected him to receive the 2019 Klaus Halbach Award for Innovative Instrumentation. “I thought they’d mistaken the nominator for the nominee!” Tamura said.
There was no mistake. The UEC recognized Tamura, an ALS staff scientist, for “the development of software for analysis of microdiffraction data, which has been critical to the success of science programs at facilities around the world.” As a postdoc working on the x-ray microdiffraction station at the Advanced Photon Source, Tamura was recruited to the ALS to do similar work. Although microdiffraction capabilities were becoming more sophisticated, the data would only be useful with analysis tools that could keep up with data collection. So, Tamura taught himself FORTRAN and began developing such a tool. He completed the first version just before Christmas 1999, which inspired the name X-ray Microdiffraction Analysis Software, or XMAS. In the two decades since, the software has been a gift for many in the community.
In an early study using XMAS, researchers deployed synchrotron-based x-ray diffraction to characterize individual grains in thin films and then applied the software to interpret the data. Shining white (polychromatic) light onto the samples produced complex signals called Laue patterns, but the existing tools for indexing Laue patterns had been limited. “We were creating thousands of patterns. XMAS helped us automate the process in order to look at more complicated problems,” Tamura explained. “It continues to organically grow, adding new data analysis tools beyond simply indexing patterns.”
The Laue diffraction experiments Tamura runs at Beamline 12.3.2 use polychromatic beam, but Tamura has added simulation tools and ways to analyze monochromatic beam data. The many capabilities of XMAS have sped up and enhanced the analysis of quartz crystals from volcanic eruptions and fallout debris from the atomic bomb blast in Hiroshima, among other projects. Other facilities around the world have started using XMAS, and Tamura spends a lot of time training users so they can take advantage of the tool. “Some of them are really proficient—they actually know XMAS better than me,” he said.
The wide adoption of XMAS has not gone unnoticed. ALS colleague Dula Parkinson described Tamura’s role in pioneering the superfacility concept, which unites computing, networking, and algorithms with the experimental capabilities. “He also developed versions of XMAS that run on clusters at the ALS (maintained by the Laboratory Research Computing) as well as at NERSC [the National Energy Research Scientific Computing Center].” Parkinson added, “Nobu and his team additionally developed an easy-to-use graphical interface for the software, including a web portal for NERSC.”
Tamura sees the development of XMAS as an essential part of the capabilities offered at Beamline 12.3.2, and he is excited by the possibilities of machine learning and how it might expand the functionality of XMAS. Outside the demands of his job description, he continues teaching himself to code to further expand the toolkit. From the impact of XMAS to his paleoart, it is clear that even a “side hobby” for Tamura leads to impressive results.
Klaus Halbach was a senior staff scientist at LBNL who pioneered the development of undulators using permanent magnets, and other innovations in accelerator physics. Even though he retired from LBNL in 1991, he remained active in lab projects and student training until his death in 2000.