Courtesy of Laura Newburgh

Laura Newburgh, assistant professor of physics, was honored by the American Astronomical Society (AAS) as part of a team that has made strides in observing the phenomenon of fast radio bursts, or FRBs.

The AAS recently announced that the 2022 Lancelot M. Berkeley New York Community Trust Prize for Meritorious Work in Astronomy will be presented to members of the Canadian Hydrogen Intensity Mapping Experiment (CHIME), which includes Newburgh. This year’s award is unique in that it is the first time the award will be given to a team rather than to a specific individual.

“Speaking personally because I know this, the leader does some tiny, tiny fraction of what the team does,” said Mark Halpern, principal investigator of CHIME. “In this day and age, this is just the realistic and appropriate thing to do. This discovery, the catalog and finding the magnetar, this is the work of a hundred people, eight of which are at Yale. It would not be appropriate to just name one or two, so we were very happy that the AAS saw their way to naming the full team as the recipient.”

CHIME’s initial goal was to understand why the expansion of the universe is accelerating rather than slowing down in the context of dark energy. To accomplish this, the team constructed a stationary radio telescope capable of measuring neutral hydrogen in the galaxy. Since the wavelength of neutral hydrogen is known, it is possible to determine redshift, a way of quantifying distance, when the telescope detects the wavelength at different values. This information can then be used to create a three-dimensional survey of the sky on a much larger scale than what an ordinary radio telescope would be able to accomplish.

The region of the sky that CHIME observes is referred to as the beam of its telescope. However, it is difficult to measure the individual power of sources in the sky because when CHIME measures a source, it collects data that comes from both the source and the rest of the sky. To remedy this, Newburgh uses a technique called holography with a device that she built during her postdoctoral fellowship at the University of Toronto. 

“[CHIME’s] view of the sky is different from most radio telescopes,” Newburgh said. “As a result, we’re measuring these things that other radio telescopes haven’t and it has meant that you’re in a whole new regime for analysis and instrumentation and calibration. That is both terrifying but also really fun. That’s really my favorite thing about CHIME.”

When a source rotates through CHIME’s beam, Newburgh’s creation — which sits on a separate steerable dish — tracks the telescope’s beam and transfers the data to CHIME. When the two datasets are combined, it is possible to determine the energy source’s individual power and measure that slice of CHIME’s beam with high accuracy. 

Newburgh has worked with CHIME since 2013. In addition to her work with holography, Newburgh was also involved in the early stages of CHIME when a small version of the telescope was being constructed to test the design before it was replicated on a larger scale. Ue-Li Pen, a founding member of CHIME and professor at the University of Toronto, described Newburgh as having the “magic touch” when it comes to making things in the project work. 

“There’s one experience I’m sure [Newburgh] remembers very clearly, with this 50 meter telescope when we were installing a feed and a receiver a long ways up above the surface where we had an accident and the whole package came falling down,” Pen said. “She was standing there. Several weeks of work were just flying down and shattering into pieces in front of her, and we thought that was the end, but she never gave up. She collected the pieces and we all thought this was going to be the end of many months of work, but no, she took Krazy Glue and glued it all together and it worked again.”

Gary Hinshaw, a professor at the University of British Columbia and a founding member of CHIME, echoed Pen’s assessment of Newburgh’s pivotal contributions towards the project.

“She and I worked together on a particular aspect of understanding how the instrument works,” Hinshaw said. “She’s been a great asset to that effort. We’re really glad that she was a postdoc with us and that she was able to move on to Yale and be a successful faculty member there.”

Newburgh’s work on the project proved to be essential in the research that led to the AAS award. The nature of CHIME’s design makes it a reliable source for observing pulsars, which are spinning neutron stars that emit flashes of light, as well as FRBs. Over the course of its first year of operation in 2018, CHIME detected 536 FRBs and currently detects around 1,000 per year.

In 2020, CHIME made a crucial observation of an FRB caused by a magnetar, which is a rotating neutron star associated with a large magnetic field. Due to Newburgh’s work measuring the telescope’s angular response, the team was able to measure the shape of CHIME’s beam in the magnetar’s region and in turn, determine the burst’s brightness. Halpern described this burst as “a once in a lifetime” occurrence. Now, with a potential link to magnetars as a source for FRBs, the work accomplished by CHIME could lead to a greater understanding of this astronomical phenomenon. 

“It’s amazing how far we’ve gone from freezing in the rain building the telescope to exciting high-profile science results,” said Paul Scholz, a Dunlap fellow at the University of Toronto and a member of the CHIME collaboration. “It’s been a journey.”

The award will be officially accepted by members of the CHIME/FRB team at the Salt Palace Convention Center in Salt Lake City, Utah on Jan. 13, 2022.

This AAS conference is colloquially referred to as the “Super Bowl of Astronomy.”

ELIZABETH WATSON
Elizabeth Watson covers breakthrough research for SciTech and illustrates for various sections. She is a first year in Pauli Murray College and is planning to major in STEM and the humanities.