تقرير
On the Kinematics of Cold, Metal-enriched Galactic Fountain Flows in Nearby Star-forming Galaxies
| العنوان: | On the Kinematics of Cold, Metal-enriched Galactic Fountain Flows in Nearby Star-forming Galaxies |
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| المؤلفون: | Rubin, Kate H. R., Juarez, Christian, Cooksey, Kathy L., Werk, Jessica K., Prochaska, J. Xavier, O'Meara, John M., Burchett, Joseph N., Vaught, Ryan J. Rickards, Kulkarni, Varsha P., Straka, Lorrie A. |
| سنة النشر: | 2022 |
| المجموعة: | Astrophysics |
| مصطلحات موضوعية: | Astrophysics - Astrophysics of Galaxies |
| الوصف: | We use medium-resolution Keck/Echellette Spectrograph and Imager spectroscopy of bright quasars to study cool gas traced by CaII 3934,3969 and NaI 5891,5897 absorption in the interstellar/circumgalactic media of 21 foreground star-forming galaxies at redshifts 0.03 < z < 0.20 with stellar masses 7.4 < log M_*/M_sun < 10.6. The quasar-galaxy pairs were drawn from a unique sample of Sloan Digital Sky Survey quasar spectra with intervening nebular emission, and thus have exceptionally close impact parameters (R_perp < 13 kpc). The strength of this line emission implies that the galaxies' star formation rates (SFRs) span a broad range, with several lying well above the star-forming sequence. We use Voigt profile modeling to derive column densities and component velocities for each absorber, finding that column densities N(CaII) > 10^12.5 cm^-2 (N(NaI) > 10^12.0 cm^-2) occur with an incidence f_C(CaII) = 0.63^+0.10_-0.11 (f_C(NaI) = 0.57^+0.10_-0.11). We find no evidence for a dependence of f_C or the rest-frame equivalent widths W_r(CaII K) or W_r(NaI 5891) on R_perp or M_*. Instead, W_r(CaII K) is correlated with local SFR at >3sigma significance, suggesting that CaII traces star formation-driven outflows. While most of the absorbers have velocities within +/-50 km/s of the host redshift, their velocity widths (characterized by Delta v_90) are universally 30-177 km/s larger than that implied by tilted-ring modeling of the velocities of interstellar material. These kinematics must trace galactic fountain flows and demonstrate that they persist at R_perp > 5 kpc. Finally, we assess the relationship between dust reddening and W_r(CaII K) (W_r(NaI 5891)), finding that 33% (24%) of the absorbers are inconsistent with the best-fit Milky Way E(B-V)-W_r relations at >3sigma significance. Comment: 38 pages, 16 figures, 4 tables. Accepted to ApJ |
| نوع الوثيقة: | Working Paper |
| DOI: | 10.3847/1538-4357/ac7b88 |
| URL الوصول: | http://arxiv.org/abs/2208.04973 |
| رقم الأكسشن: | edsarx.2208.04973 |
| قاعدة البيانات: | arXiv |
| DOI: | 10.3847/1538-4357/ac7b88 |
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