%0 Generic %1 furlanetto2021bursty %A Furlanetto, Steven R. %A Mirocha, Jordan %D 2021 %K library %T Bursty star formation during the Cosmic Dawn driven by delayed stellar feedback %U http://arxiv.org/abs/2109.04488 %X In recent years, several analytic models have demonstrated that simple assumptions about halo growth and feedback-regulated star formation can match the (limited) existing observational data on galaxies at z>6. By extending such models, we demonstrate that imposing a time delay on stellar feedback (as inevitably occurs in the case of supernova explosions) induces burstiness in small galaxies. Although supernova progenitors have short lifetimes (~5-30 Myr), the delay exceeds the dynamical time of galaxies at such high redshifts. As a result, star formation proceeds unimpeded by feedback for several cycles and övershoots" the expectations of feedback-regulated star formation models. We show that such overshoot is expected even in atomic cooling halos, with masses up to ~10^10.5 Msun at z>6. However, these burst cycles damp out quickly in massive galaxies, because large haloes are more resistant to feedback so retain a continuous gas supply. Bursts in small galaxies - largely beyond the reach of existing observations - induce a scatter in the luminosity of these haloes (of ~1 mag) and increase the time-averaged star formation efficiency by up to an order of magnitude. This kind of burstiness can have substantial effects on the earliest phases of star formation and reionization.

@misc{furlanetto2021bursty, abstract = {In recent years, several analytic models have demonstrated that simple assumptions about halo growth and feedback-regulated star formation can match the (limited) existing observational data on galaxies at z>6. By extending such models, we demonstrate that imposing a time delay on stellar feedback (as inevitably occurs in the case of supernova explosions) induces burstiness in small galaxies. Although supernova progenitors have short lifetimes (~5-30 Myr), the delay exceeds the dynamical time of galaxies at such high redshifts. As a result, star formation proceeds unimpeded by feedback for several cycles and "overshoots" the expectations of feedback-regulated star formation models. We show that such overshoot is expected even in atomic cooling halos, with masses up to ~10^10.5 Msun at z>6. However, these burst cycles damp out quickly in massive galaxies, because large haloes are more resistant to feedback so retain a continuous gas supply. Bursts in small galaxies - largely beyond the reach of existing observations - induce a scatter in the luminosity of these haloes (of ~1 mag) and increase the time-averaged star formation efficiency by up to an order of magnitude. This kind of burstiness can have substantial effects on the earliest phases of star formation and reionization.}, added-at = {2021-09-13T10:06:44.000+0200}, author = {Furlanetto, Steven R. and Mirocha, Jordan}, biburl = {https://www.bibsonomy.org/bibtex/26430c49ecef2a6a2a07266f5b48bc4fb/gpkulkarni}, description = {Bursty star formation during the Cosmic Dawn driven by delayed stellar feedback}, interhash = {b1f0afc5097f0540b476f95aba44c567}, intrahash = {6430c49ecef2a6a2a07266f5b48bc4fb}, keywords = {library}, note = {cite arxiv:2109.04488Comment: 15 pages, 10 figures, submitted to MNRAS}, timestamp = {2021-09-13T10:06:44.000+0200}, title = {Bursty star formation during the Cosmic Dawn driven by delayed stellar feedback}, url = {http://arxiv.org/abs/2109.04488}, year = 2021 }