Denser and more turbulent environments tend to form multiple stars, study finds

The Chinese Academy of Sciences is located in Beijing.

Nearly half of the stars in the universe are formed in multiple stellar systems, which are thought to include twins, triplets, and quadruplets.

Recent studies of stellar nurseries have focused more on how single stars form. Astronomers have been stumped by the origin of the multiple stellar system.

A team led by researchers from the Chinese Academy of Sciences has discovered that denser and more turbulent environments are more likely to produce multiple stars.

The study was published in a journal

The birth of a star requires the collapse of cold dense pockets of gas and dust in the clouds. The properties of the dense cores affect the number of stars.

The closest active star formation region to Earth was looked at by the researchers using the James Clerk Maxwell Telescope in Hawaii and the ALMA in Chile. The stellar nursery is an ideal place to test various models of star formation.

The scientists were able to identify 49 cold, dense core in the clouds that are in the process of forming young stars. The internal structures within these dense cores were revealed using ALMA.

The researchers found that about 13 dense cores are giving birth to multiple stars while the other cores are only forming single stars. The physical characteristics of the dense cores were estimated by them.

They found that the H 2 gas density and mass of the core of a multiple star is higher than that of a single star. According to the first author of the study, self-gravity inside the core causes it to be easier to fragment.

The team used the Nobeyama 45 meter telescope to observe the 49 cores in the N 2 H +. N 2 H + line width is larger for cores forming multiple stars than it is for single stars. The Nobeyama observations can be used to measure turbulence levels. Prof. Ken'ichi Tatematsu led the Nobeyama observations.

In this study, we found that multiple stars form in denser and more turbulent core.

For ALMA follow-up,JCMT has proved to be a great tool. With ALMA providing unprecedented sensitivity and resolution, we can do similar studies on a much larger sample of dense core for a more thorough understanding of star formation.

Magnetic fields have yet to be looked at in our analysis. The dense core may be affected by magnetic fields. The author of the study and lead for the ALMA data is excited to focus the next stage of the research on this area.

More information: Qiu-yi Luo et al, ALMA Survey of Orion Planck Galactic Cold Clumps (ALMASOP): How Do Dense Core Properties Affect the Multiplicity of Protostars?, The Astrophysical Journal (2022). DOI: 10.3847/1538-4357/ac66d9 Journal information: Astrophysical Journal Provided by Chinese Academy of Sciences