Studying [C II] emission in low-mass galaxies at z ~ 7Glazer, Kelsey (Avtor) Bradač, Maruša (Avtor) Sanders, Ryan L. (Avtor) Fujimoto, Seiji (Avtor) Bolan, Patricia (Avtor) Ferrara, Andrea (Avtor) Strait, Victoria (Avtor) Jones, Tucker (Avtor) Lemaux, Brian C. (Avtor) high-redshift galaxiesgravitational lensingWe report on a [CII]$_{158\mu\mathrm{m}}$ search using the Atacama Large Millimeter/submillimeter Array (ALMA) on three lensed, confirmed Ly$\alpha$ emitting galaxies at z ∼ 7. Our targets are ultraviolet (UV) faint systems with stellar masses on the order of M$_*$ ∼ $10^9\ \mathrm{M}_{\odot}$. We detect a single [C II] line emission (4$\sigma$) from the brightest (L ∼ 2.4 × $10^{10}\ \mathrm{L}_\odot$) galaxy in our sample, MACS0454-1251. We determine a systemic redshift (z$_{[C II]}$ = 6.3151 ± 0.0005) for MACS0454-1251 and measure a Ly$\alpha$ velocity offset of $\Delta v \approx 300 \pm 70\mathrm{km\ s^{-1}}$⁠. The remaining two galaxies we detect no [C II] but provide 3$\sigma$ upper limits on their [C II] line luminosities which we use to investigate the $L_{[C II]}-\mathrm{SFR}$ relation. Overall our single [C II] detection shows agreement with the relation for local dwarf galaxies. Our [C II] deficient galaxies could potentially be exhibiting low metallicities (Z < Z$_{\odot}$). Another possible explanation for weaker [C II] emission could be strong feedback from star formation disrupting molecular clouds. We do not detect continuum emission in any of the sources, placing upper limits on their dust masses. Assuming a single dust temperature of $T_d=35\mathrm{K}$ dust masses ($\mathrm{M_{dust}}$) range from < 4.8 × $10^7\ \mathrm{M}_\odot$ to 2.3 × $10^8\ \mathrm{M}_\odot$. Collectively, our results suggest faint reionization era sources could be metal poor and/or could have strong feedback suppressing [C II] emission.20242024-08-27 15:53:55Članek v reviji160387sl