New tool refines exoplanet search
|An artist's conception of an exoplanet |
For certain kinds of low-mass stars, however, there are limitations to the standard radial velocity method, which can cause false positives -- in other words, find something that looks like a planet, but isn't.
To address this issue, Gagne, Gao, and Plavchan decided to use the radial velocity technique, but they examined a different, longer wavelength of light.
|The tool that allowed the team to improve planet hunting in the near-infrared|
— a cell that contains methane gas [Credit: Peter Plavchan]
Radial velocity work in the near-infrared wavelengths has been conducted before, but it has trailed behind planet hunting in the visible spectrum, partially due to technical challenges. The research team was able to develop a better calibration tool to improve the overall technology for near-infrared radial velocity work, which should make it a better option going forward.
They examined 32 low-mass stars using this technological upgrade atthe NASA Infrared Telescope Facility atop Mauna Kea, Hawaii. Their findings confirmed several known planets and binary systems, and also identified a few new planetary candidates.
"Our results indicate that this planet-hunting tool is precise and should be a part of the mix of approaches used by astronomers going forward," Gao said. "It's amazing to think that two decades ago we'd only just confirmed exoplanets actually existed and now we're able to refine and improve those methods for further discoveries."
Source: Carnegie Institution for Science [April 12, 2016]