IIA scientists find unique star that defies star formation theories
What's the story
Scientists at the Indian Institute of Astrophysics (IIA) in Bengaluru have discovered a unique star, HE 1005-1439, which challenges previous understanding of star formation.
This star appears to have formed through a combination of two different neutron-capture processes which were previously believed to occur in separate astrophysical environments.
The discovery can provide insights into how various star formation processes influence elemental composition of stars.
Details
Researchers relied on high-resolution spectroscopic data from Japan's SUBARU telescope
Using data from the High Dispersion Spectrograph attached to Japan's SUBARU telescope, the team analyzed the star's surface chemical composition.
They found HE 1005-1439 has an iron content thousand times less than the Sun and is abundant in neutron-capture elements. Theoretical models could not explain the observed elemental abundance.
Hence, the team went ahead with a parametric analysis to understand the obtained abundance pattern.
Explanation
'The observed abundance pattern is quite unique'
Defying current models, HE 1005-1439 is classified as a carbon-enhanced metal-poor (CEMP) star.
"For the first time, we came across an object with a surface chemical composition that exhibits contributions from both slow(s) and intermediate (i) neutron-capture nucleosynthesis," said Partha Pratim Goswami, who led the research.
"The observed abundance pattern is quite unique and has never been observed before in any CEMP stars."
Official words
'The star's composition being influenced by two processes is surprising'
"Our analysis clearly indicates that the star's surface chemical composition is being influenced by similar contributions from both the s- and i-process," added Goswami.
"The s- and i-process occur in different astrophysical environments, and hence, the surface chemical composition of HE 1005-1439 being influenced by both processes seemed quite surprising."
The study has been published in the peer-reviewed scientific journal Astronomy and Astrophysics.