Carnegie Mellon University

Rachel Mandelbaum

April 11, 2019

Mandelbaum Elected Spokesperson for LSST Dark Energy Science Collaboration

Jocelyn Duffy
  • Associate Dean for Communications, Mellon College of Science
  • 412-268-9982

Carnegie Mellon University Associate Professor of Physics Rachel Mandelbaum has been elected as the spokesperson for the Large Synoptic Survey Telescope’s (LSST) Dark Energy Science Collaboration (DESC). Mandelbaum will serve as spokesperson-elect until her two-year term begins on July 1.

Dark energy is the mysterious force that drives the universe’s accelerating expansion. The LSST, an 8.4-meter ground-based telescope being constructed in Cerro Pachón, Chile, will image the entire visible sky every few nights. It will collect data for 10 years, effectively creating a movie that will allow cosmologists to view billions of galaxies in the universe and monitor how they change over time. Within this dataset is information that will allow researchers to measure, with unprecedented precision, how the universe has expanded over time, which tells us about the properties of dark energy.   

Currently, the LSST is in its final stages of construction, with its primary/tertiary mirror traveling from the University of Arizona in Tucson, where it was constructed, to Chile via a five-week-long boat trip. Construction is scheduled to be completed in 2021 and operations are scheduled to begin in 2022.

In preparation for the first commissioning data that will become available in 2021, members of the LSST DESC are hard at work, building up the scientific infrastructure that is needed to interpret the vast amounts of data that the telescope will gather. As spokesperson, Mandelbaum will lead the DESC in the final stages of preparation for the LSST’s first observations, including overseeing its scientific, computing and technical direction, overall collaboration organization and finances (serving as a liaison to funding agencies).

“LSST is going to be a game-changer for our understanding of the cosmological model of the universe. I am very excited to lead the LSST DESC at such a critical time in its preparation for this amazing new dataset,” Mandelbaum said. 

Since July 2015, Mandelbaum has served as the DESC’s analysis coordinator, making her responsible for overseeing the collaboration’s high priority analysis tasks and seven analysis working groups. Before that she served as a co-leader of the weak lensing working group.

A member of the Carnegie Mellon Physics faculty and the McWilliams Center for Cosmology since 2011, Mandelbaum is a leader in the field of weak gravitational lensing, a technique used to measure the large-scale distribution of ordinary and dark matter in the universe. She has been recognized for her work with the Annie Jump Cannon Prize from the American Astronomical Society, a Department of Energy Early Career Award and an Alfred P. Sloan Fellowship.