English

Most planets might have more than 5 Myr of time to form

Astrophysics of Galaxies 2022-10-06 v1

Abstract

The lifetime of protoplanetary disks is a crucial parameter for planet formation research. Observations of disk fractions in star clusters imply median disk lifetimes of 1 -- 3 Myr. This very short disk lifetime calls for planet formation to occur extremely rapidly. We show that young, distant clusters (\leq 5 Myr, >> 200 pc) often dominate these types of studies. Such clusters frequently suffer from limiting magnitudes leading to an over-representation of high-mass stars. As high-mass stars disperse their disks earlier, the derived disk lifetimes apply best to high-mass stars rather than low-mass stars. Including only nearby clusters (<< 200 pc) minimizes the effect of limiting magnitude. In this case, the median disk lifetime of low-mass stars is with 5 -- 10 Myr, thus much longer than often claimed. The longer timescales provide planets ample time to form. How high-mass stars form planets so much faster than low-mass stars is the next grand challenges.

Keywords

Cite

@article{arxiv.2210.02420,
  title  = {Most planets might have more than 5 Myr of time to form},
  author = {Susanne Pfalzner and Shahrzad Dehghani and Arnaud Michel},
  journal= {arXiv preprint arXiv:2210.02420},
  year   = {2022}
}

Comments

10 pages, 3 figures, accepted for ApJL