The U.S. Department of Energy, or DOE, has selected Lawrence Berkeley National Laboratory, or Berkeley Lab, to be a part of one of the largest collaborative efforts taken to study the relic light emitted by the universe.
The Cosmic Microwave Background Stage 4, or CMB-S4, experiment will combine several existing study partnerships to examine the microwave sky with 550,000 ultrasensitive detectors over the course of seven years, according to CMB-S4 spokesperson Julian Borrill. These detectors will be placed on 21 telescopes to view space from two central places: the South Pole and the high Atacama Desert in Chile, according to Borrill.
“The primary goals of CMB-S4 are to determine when and how inflation happened – inflation is the very early moment in the universe’s history when it underwent a brief period of exponential expansion — to understand the invisible contents of the universe, including light relic particles, dark matter, and dark energy,” Borrill said in an email.
By reading temperature variations of cosmic microwave background, or CMB, light, scientists are able to debrief the entire history of the universe, according to Borrill. Since these variations are so tiny, many ultrasensitive detectors are needed to scan the sky and detect them, Borrill said.
Borrill added that the project will help answer questions that touch upon fundamental physics, cosmology, astrophysics and astronomy.
“We are currently optimizing the design of the experiment,” Borrill said in the email. “We anticipate construction starting in 2022, deployment and commissioning in 2026, and full science observations in 2028. This will be a defining CMB dataset though, so it will continue to be analyzed and interpreted by other scientists for decades beyond this.”
When the project was proposed in 2013, it was clear that the size of the project required the help of DOE laboratories, according to Borrill. He added that Argonne Nation Laboratory, Berkeley Lab, Fermilab and SLAC National Accelerator Laboratory have all played large roles in finding footing for this project, with three of the labs being asked to submit a proposal to DOE to lead the project.
DOE ultimately selected Berkeley Lab to lead the project. By drawing on the talents of all those contributing to this project, Berkeley Lab will be able to access the help it needs for a successful run, according to Borrill.
“The CMB is a unique source of information about the formation, evolution, and destiny of our universe,” Borrill said in the email. “Alongside the extraordinary breadth and depth of the science, CMB-S4 is a prime example of what we are capable of when we combine resources and expertise across communities and agencies, each bringing its unique strengths to enable something none could do alone.”
