A researcher from the Indian Institute of Astrophysics (IIA), working with collaborators from Institut de Recherche en Astrophysique et Planétologie, France, have developed a method to compute more realistic properties of stellar atmospheres.
This method is claimed to open the door to more realistic simulations of stellar spectra which is the first software astronomers use to decode the bodily situations in stars, circumstellar disks, and interstellar clouds.
Until now, most fashions relied on an essential simplification wherein it was assumed that whereas atoms might deviate from equilibrium in phrases of vitality states, their velocities (how briskly they transfer round) nonetheless adopted a neat, predictable distribution.
“This assumption, while convenient, is not always realistic, especially for atoms in short-lived excited states,” the Department of Science and Technology stated.
It added that stellar atmospheres are chaotic, photons scatter, vitality ranges fluctuate, and velocity distributions can stray from the equilibrium image.
“Capturing this complexity requires what astrophysicists call full non-local thermodynamic equilibrium (FNLTE) radiative transfer — a formidable problem that scientists first described back in the 1980s but couldn’t solve owing to computational limitations,” the division stated.
The IIA researcher, Sampoorna M., and the French team first tackled a simplified model of the FNLTE downside: the case of a two-level atom (the place an atom can solely leap between two vitality states) and then took the following step of fixing the three-level atom downside.
“With three atomic levels, new types of scattering come into play, including Raman scattering — where an atom absorbs light and re-emits it at a different frequency. These processes are only approximated in standard models, but the new FNLTE approach captures them naturally,” it added.
When the team in contrast their FNLTE outcomes to conventional fashions, the variations had been hanging. The velocity distribution of excited hydrogen atoms now not adopted the tidy Maxwellian curve. Instead, it confirmed vital departures, particularly close to the stellar floor — precisely the place astronomers accumulate their spectral fingerprints of stars.
This advance means astrophysicists are actually a step nearer to simulating stellar spectra with unprecedented realism. “More accurate models help astronomers pinpoint the temperatures and compositions of stars more reliably, better understand the physics of circumstellar disks and molecular clouds where stars and planets form and push forward the search for Earth-like exoplanets, since decoding starlight is key to finding tiny planetary signatures,” the division stated.
