Tag Archive for BOSS
By collecting tens of thousands of quasar spectra, the Baryon Oscillation Spectroscopic Survey (BOSS) has measured the large-scale structure of the early universe for the first time. Like backlights in the fog, the quasars illuminate clouds of hydrogen gas along the line of sight. No other technique can reach back over 10 billion years to probe structure at a time when the expansion of the universe was still decelerating and dark energy was yet to turn on.
Mounted on a telescope high in the Andes, the Dark Energy Camera (DECam) saw first light September 12. DECam’s half-billion-pixel focal plane is made of Berkeley Lab CCDs, descended from sensors developed for high-energy physics by Berkeley Lab scientists and engineers. Highly sensitive to the near-infrared region of the spectrum, Berkeley Lab CCDs are an essential component of the most powerful dark-energy survey instrument yet made.
Now freely available to the public: spectroscopic data from over half a million galaxies up to 7 billion light years away, over a hundred thousand quasars up to 11.5 billion light years away, and tens of thousands of stars and other astronomical objects in the Sloan Digital Sky Survey’s Data Release 9. This data is just the first year and a half of observation by BOSS, the Baryon Oscillation Spectroscopic Survey led by Berkeley Lab scientists. BOSS is the largest spectroscopic survey ever made to measure the evolution of large-scale galactic structure.