تقرير
RIOJA. Complex Dusty Starbursts in a Major Merger B14-65666 at z=7.15
| العنوان: | RIOJA. Complex Dusty Starbursts in a Major Merger B14-65666 at z=7.15 |
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| المؤلفون: | Sugahara, Yuma, Álvarez-Márquez, Javier, Hashimoto, Takuya, Colina, Luis, Inoue, Akio K., Costantin, Luca, Fudamoto, Yoshinobu, Mawatari, Ken, Ren, Yi W., Arribas, Santiago, Bakx, Tom J. L. C., Blanco-Prieto, Carmen, Ceverino, Daniel, Gómez, Alejandro Crespo, Hagimoto, Masato, Hashigaya, Takeshi, Marques-Chaves, Rui, Matsuo, Hiroshi, Nakazato, Yurina, Pereira-Santaella, Miguel, Tamura, Yoichi, Usui, Mitsutaka, Yoshida, Naoki |
| سنة النشر: | 2024 |
| المجموعة: | Astrophysics |
| مصطلحات موضوعية: | Astrophysics - Astrophysics of Galaxies |
| الوصف: | We present JWST NIRCam imaging of B14-65666 ("Big Three Dragons"), a bright Lyman-break galaxy system ($M_\text{UV}=-22.5$ mag) at $z=7.15$. The high angular resolution of NIRCam reveals the complex morphology of two galaxy components: galaxy E has a compact core (E-core), surrounded by diffuse, extended, rest-frame optical emission, which is likely to be tidal tails; and galaxy W has a clumpy and elongated morphology with a blue UV slope ($\beta_\text{UV}=-2.2\pm0.1$). The flux excess, F356W$-$F444W, peaks at the E-core ($1.05^{+0.08}_{-0.09}$ mag), tracing the presence of strong [OIII] 4960,5008 \r{A} emission. ALMA archival data show that the bluer galaxy W is brighter in dust continua than the redder galaxy E, while the tails are bright in [OIII] 88 $\mathrm{\mu m}$. The UV/optical and sub-mm SED fitting confirms that B14-65666 is a major merger in a starburst phase as derived from the stellar mass ratio (3:1 to 2:1) and the star-formation rate, $\simeq1$ dex higher than the star-formation main sequence at the same redshift. The galaxy E is a dusty ($A_\text{V}=1.2\pm0.1$ mag) starburst with a possible high dust temperature ($\ge63$-$68$ K). The galaxy W would have a low dust temperature ($\le27$-$33$ K) or patchy stellar-and-dust geometry, as suggested from the infrared excess (IRX) and $\beta_\text{UV}$ diagram. The high optical-to-FIR [OIII] line ratio of the E-core shows its lower gas-phase metallicity ($\simeq0.2$ Z$_{\odot}$) than the galaxy W. These results agree with a scenario where major mergers disturb morphology and induce nuclear dusty starbursts triggered by less-enriched inflows. B14-65666 shows a picture of complex stellar buildup processes during major mergers in the epoch of reionization. Comment: 18 pages, 6 figures, 4 tables. Submitted to ApJ |
| نوع الوثيقة: | Working Paper |
| URL الوصول: | http://arxiv.org/abs/2403.17133 |
| رقم الأكسشن: | edsarx.2403.17133 |
| قاعدة البيانات: | arXiv |
| الوصف غير متاح. |