The effect of radiative feedback on disc fragmentation

Mercer, Anthony Paul and Stamatellos, Dimitris orcid iconORCID: 0000-0002-4502-8344 (2017) The effect of radiative feedback on disc fragmentation. Monthly Notices of the Royal Astronomical Society MNRAS, 465 (1). pp. 2-18. ISSN 0035-8711

[thumbnail of Version of record - open access]
PDF (Version of record - open access) - Published Version
Available under License Creative Commons Attribution Non-commercial No Derivatives.


Official URL:


Protostellar discs may become massive enough to fragment producing secondary low-mass objects: planets, brown dwarfs and low-mass stars. We study the effect of radiative feedback from such newly-formed secondary objects using radiative hydrodynamic simulations. We compare the results of simulations without any radiative feedback from secondary objects with those where two types of radiative feedback are considered: (i) continuous, and (ii) episodic. We find that: (i) continuous radiative feedback stabilizes the disc and suppresses further fragmentation, reducing the number secondary objects formed; (ii) episodic feedback from secondary objects heats and stabilises the disc when the outburst occurs, but shortly after the outburst stops, the disc becomes unstable and fragments again. However, fewer secondary objects are formed compared to the the case without radiative feedback. We also find that the mass growth of secondary objects is mildly suppressed due to the effect of their radiative feedback. However, their mass growth also depends on where they form in the disc and on their subsequent interactions, such that their final masses are not drastically different from the case without radiative feedback. We find that the masses of secondary objects formed by disc fragmentation are from a few MJ to a few 0.1 M0. Planets formed by fragmentation
tend to be ejected from the disc. We conclude that planetary-mass objects on wide orbits (wide-
orbit planets) are unlikely to form by disc fragmentation. Nevertheless, disc fragmentation may be a significant source of free-floating planets and brown dwarfs.

Repository Staff Only: item control page