The POLARBEAR collaboration made the most precise measurement of the polarization of the cosmic microwave background to date.
POLARBEAR is a team of 70 scientists who have been studying the universe's oldest light using a telescope high in Chile's Atacama desert, the University of California - San Diego reported. The light is leftover radiation from the Big Bang, which cooled and stretched to microwave lengths as the universe expanded in it earliest days.
"It's a really important milestone," said Kam Arnold, a research scientist at UC San Diego's Center for Astrophysics and Space Sciences and part of the cosmology group "We're in a new regime of more powerful, precision cosmology."
The researchers created ultra-sensitive instruments called bolometers, which observe the direction of the light's electrical field from different points in the sky.
"It's a map of all these little directions that the light's electric field is pointing," Arnold explained.
The team has now successfully mapped these angles with a resolution on a scale of about 3 arcminutes, which is equivalent to one-tenth the diameter of the full moon. Through their research the scientists observed B-modes in the patterns of polarization, indicating microwave light in the universe has been warped by phenomena such as mysterious dark matter and aloof neutrinos.
Dust is our own galaxy is also known to emit polar radiation, which has interfered with measurements of the cosmic microwave background; the three patches observed by POLARBEAR are believed to be relatively free of these influences.
"We are confident that these B-modes are cosmological rather than galactic in origin," Arnold said.
In the future the researchers plan to continue these observations using additional telescopes from the Simons Array, creating an even wider map of this ancient light.
"POLARBEAR is a real tour de force. With a relatively small, but strong, UC-led team we have surpassed the next-nearest competitors by an order of magnitude in sensitivity. We have paved the way towards solving the deepest mysteries in the quest to understand matter and energy at the beginning of time," said team leader Brian Keating.
The findings were published Oct. 20 in the Astrophysical Journal.
