A formation scenario of young stellar groups in the region of the Scorpio Centaurus OB association

TL;DR

This paper proposes a formation scenario for young stellar groups in the Sco-Cen OB association, emphasizing the influence of shells and collisions of bubbles blown by LCC and UCL on star formation.

Contribution

It introduces a dynamical evolution model linking shell interactions from LCC and UCL to the formation of specific young stellar groups.

Findings

Beta Pictoris and TW Hydrae formed in shell wakes

Eta Chamaeleontis resulted from shell collision

Upper Scorpius may have formed similarly to eta Chamaeleontis

Abstract

The main objective of this work is to investigate the role played by Lower Centaurus Crux (LCC) and Upper Centaurus Lupus (UCL), both subcomponents of the Scorpio Centaurus OB association (Sco-Cen), in the formation of the groups beta Pictoris, TW Hydrae and the eta Chamaeleontis cluster. The dynamical evolution of all the stellar groups involved and of the bubbles and shells blown by LCC and UCL are calculated and followed from the past to the present. This leads to a formation scenario in which (1) the groups beta Pictoris, TW Hydrae were formed in the wake of the shells created by LCC and UCL, (2) the young cluster eta Chamaeleontis was born as a consequence of the collision of the shells of LCC and UCL, and (3) the formation of Upper Scorpius (US), the other main subcomponent of the Sco-Cen association, may have been started by the same process that created eta Chamaeleontis.