%0 Generic %1 citeulike:13897700 %A Mandelker, Nir %A Dekel, Avishai %A Ceverino, Daniel %A DeGraf, Colin %A Guo, Yicheng %A Primack, Joel %D 2015 %K imported %T Giant Clumps in Simulated High-z Galaxies: Properties, Evolution and Dependence on Feedback %U http://arxiv.org/abs/1512.08791 %X We study the evolution of giant clumps in high-z disc galaxies using AMR cosmological simulations at redshifts z=6-1. Our sample consists of 34 galaxies, of halo masses 10^11-10^12M\_s at z=2, run with and without radiation pressure (RP) feedback from young stars. While RP has little effect on the sizes and global stability of discs, it reduces the amount of star-forming gas by a factor of \~2, leading to a decrease in stellar mass by a similar factor by z\~2. Both samples undergo violent disc instability (VDI) and form giant clumps of masses 10^7-10^9M\_s at a similar rate, though RP significantly reduces the number of long-lived clumps. When RP is (not) included, clumps with circular velocity <40(20)km/s, baryonic surface density <200(100)M\_s/pc^2 and baryonic mass <10^8.2(10^7.3)M\_s are short-lived, disrupted in a few free-fall times. The more massive and dense clumps survive and migrate toward the disc centre over a few disc orbital times. In the RP simulations, the distribution of clump masses and star-formation rates (SFRs) normalized to their host disc is very similar at all redshifts. They exhibit a truncated power-law with a slope slightly shallower than -2. Short-lived clumps preferentially have young stellar ages, low masses, high gas fractions and specific SFRs (sSFR), and they tend to populate the outer disc. The sSFR of massive, long-lived clumps declines with age as they migrate towards the disc centre, producing gradients in mass, stellar age, gas fraction, sSFR and metallicity that distinguish them from short-lived clumps. Ex situ mergers make up \~37\% of the mass in clumps and \~29\% of the SFR. They are more massive and with older stellar ages than the in situ clumps, especially near the disc edge. Roughly half the galaxies at redshifts z=4-1 are clumpy over a wide range of stellar mass, with clumps accounting for \~3-30\% of the SFR but \~0.1-3\% of the stellar mass.

@misc{citeulike:13897700, abstract = {We study the evolution of giant clumps in high-z disc galaxies using AMR cosmological simulations at redshifts z=6-1. Our sample consists of 34 galaxies, of halo masses 10^{11}-10^{12}M\_s at z=2, run with and without radiation pressure (RP) feedback from young stars. While RP has little effect on the sizes and global stability of discs, it reduces the amount of star-forming gas by a factor of \~{}2, leading to a decrease in stellar mass by a similar factor by z\~{}2. Both samples undergo violent disc instability (VDI) and form giant clumps of masses 10^7-10^9M\_s at a similar rate, though RP significantly reduces the number of long-lived clumps. When RP is (not) included, clumps with circular velocity \<40(20)km/s, baryonic surface density \<200(100)M\_s/pc^2 and baryonic mass \<10^{8.2}(10^{7.3})M\_s are short-lived, disrupted in a few free-fall times. The more massive and dense clumps survive and migrate toward the disc centre over a few disc orbital times. In the RP simulations, the distribution of clump masses and star-formation rates (SFRs) normalized to their host disc is very similar at all redshifts. They exhibit a truncated power-law with a slope slightly shallower than -2. Short-lived clumps preferentially have young stellar ages, low masses, high gas fractions and specific SFRs (sSFR), and they tend to populate the outer disc. The sSFR of massive, long-lived clumps declines with age as they migrate towards the disc centre, producing gradients in mass, stellar age, gas fraction, sSFR and metallicity that distinguish them from short-lived clumps. Ex situ mergers make up \~{}37\% of the mass in clumps and \~{}29\% of the SFR. They are more massive and with older stellar ages than the in situ clumps, especially near the disc edge. Roughly half the galaxies at redshifts z=4-1 are clumpy over a wide range of stellar mass, with clumps accounting for \~{}3-30\% of the SFR but \~{}0.1-3\% of the stellar mass.}, added-at = {2019-03-25T08:20:55.000+0100}, archiveprefix = {arXiv}, author = {Mandelker, Nir and Dekel, Avishai and Ceverino, Daniel and DeGraf, Colin and Guo, Yicheng and Primack, Joel}, biburl = {https://www.bibsonomy.org/bibtex/28a34164d2d5b1f3b08488b8826c5ea9c/ericblackman}, citeulike-article-id = {13897700}, citeulike-linkout-0 = {http://arxiv.org/abs/1512.08791}, citeulike-linkout-1 = {http://arxiv.org/pdf/1512.08791}, day = 29, eprint = {1512.08791}, interhash = {0f36c355494a0709fd8fe7b1c8ee4010}, intrahash = {8a34164d2d5b1f3b08488b8826c5ea9c}, keywords = {imported}, month = dec, posted-at = {2016-01-04 22:39:37}, priority = {2}, timestamp = {2019-03-25T08:20:55.000+0100}, title = {{Giant Clumps in Simulated High-z Galaxies: Properties, Evolution and Dependence on Feedback}}, url = {http://arxiv.org/abs/1512.08791}, year = 2015 }