NGC 6334的灰尘偏振分发观测； Bistro揭示了高质量星形集线器网络的复杂但有组织的磁场结构的细节

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NGC 6334的灰尘偏振分发观测； Bistro揭示了高质量星形集线器网络的复杂但有组织的磁场结构的细节

Dust polarized emission observations of NGC 6334; BISTRO reveals the details of the complex but organized magnetic field structure of the high-mass star-forming hub-filament network

论文作者

Arzoumanian, D., Furuya, R., Hasegawa, T., Tahani, M., Sadavoy, S., Hull, C. L. H., Johnstone, D., Koch, P. M., Inutsuka, S. -i., Doi, Y., Hoang, T., Onaka, T., Iwasaki, K., Shimajiri, Y., Inoue, T., Peretto, N., André, P., Bastien, P., Berry, D., Chen, H. -R. V., Di Francesco, J., Eswaraiah, C., Fanciullo, L., Fissel, L. M., Hwang, J., Kang, J. -h., Kim, G., Kim, K. -T., Kirchschlager, F., Kwon, W., Lee, C. W., Liu, H. -L., Lyo, A. -R., Pattle, K., Soam, A., Tang, X., Whitworth, A., Ching, T. -C., Coudé, S., Wang, J. -W., Ward-Thompson, D., Lai, S. -P., Qiu, K., Bourke, T. L., Byun, D. -Y., Chen, M., Chen, Z., Chen, W. P., Cho, J., Choi, Y., Choi, M., Chrysostomou, A., Chung, E. J., Dai, S., Diep, P. N., Duan, H. -Y., Duan, Y., Eden, D., Fiege, J., Franzmann, E., Friberg, P., Fuller, G., Gledhill, T., Graves, S., Greaves, J., Griffin, M., Gu, Q., Han, I., Hatchell, J., Hayashi, S., Houde, M., Jeong, I. -G., Kang, M., Kang, S. -j., Kataoka, A., Kawabata, K., Kemper, F., Kim, M. -R., Kim, K. H., Kim, J., Kim, S., Kirk, J., Kobayashi, M. I. N., Konyves, V., Kusune, T., Kwon, J., Lacaille, K., Law, C. -Y., Lee, C. -F., Lee, Y. -H., Lee, S. -S., Lee, H., Lee, J. -E., Li, H. -b., Li, D., Liu, J., Liu, T., Liu, S. -Y., Lu, X., Mairs, S., Matsumura, M., Matthews, B., Moriarty-Schieven, G., Nagata, T., Nakamura, F., Nakanishi, H., Ngoc, N. B., Ohashi, N., Park, G., Parsons, H., Pyo, T. -S., Qian, L., Rao, R., Rawlings, J., Rawlings, M., Retter, B., Richer, J., Rigby, A., Saito, H., Savini, G., Scaife, A., Seta, M., Shinnaga, H., Tamura, M., Tang, Y. -W., Tomisaka, K., Tram, L. N., Tsukamoto, Y., Viti, S., Wang, H., Xie, J., Yen, H. -W., Yoo, H., Yuan, J., Yun, H. -S., Zenko, T., Zhang, G., Zhang, C. -P., Zhang, Y., Zhou, J., Zhu, L., de Looze, I., Dowell, C. D., Eyres, S., Falle, S., Friesen, R., Robitaille, J. -F., van Loo, S.

论文摘要

[删节]细丝和中心最近受到了特别关注，这要归功于研究表明它们在恒星形成中的作用。虽然已经研究了细丝和轮毂的柱密度和速度结构，但尚未表征它们的磁场（B场）。我们旨在了解B场在NGC 6334 Hub丝网络的动态演化中的作用。我们向使用JCMT/POL-2获得的NGC 6334介绍了850 $ $ m的灰尘极化发射的新观察结果。我们研究了极化强度（$ pi $），极化分数（$ pf $）和B场角（$θ_{B} $）的分布和分散。我们得出了强度的功率谱，沿山脊波峰的$θ_{B} $。我们的分析表明，当在整个区域（$ \ sim10 $ pc）上观察时，B-Field结构很复杂，但是，在较小的尺度（$ \ sim1 $ pc）下，$θ_{b} $沿丝沿细丝相干。 $θ_{b} $的观察到的功率谱可以用斜率$ -1.33 \ pm0.23 $的电源法功能很好地表示，该功能是$ \ sim20 \％$ yath，比$ i $ $ $。该结果与模拟细丝的属性兼容，可以指示形成细丝时在发挥作用的过程。 $θ_{b} $从垂直于灯丝波峰垂直于与轮毂合并时旋转。 $θ_{b} $的这种变化可能是在将物质的局部速度流入集线器上。我们的分析表明，沿这些细丝的波峰的能量平衡的变化，从远端的磁性临界/超临界到集线器附近的磁亚临界。我们检测到$ pf $的增加，这是由于新生儿恒星的出色辐射引起的晶粒对齐效率的提高可能导致的高柱密度群集群。

[Abridged] Filaments and hubs have received special attention recently thanks to studies showing their role in star formation. While the column density and velocity structures of both filaments and hubs have been studied, their magnetic fields (B-field) are not yet characterized. We aim to understand the role of the B-field in the dynamical evolution of the NGC 6334 hub-filament network. We present new observations of the dust polarized emission at 850$μ$m towards NGC 6334 obtained with the JCMT/POL-2. We study the distribution and dispersion of the polarized intensity ($PI$), the polarization fraction ($PF$), and the B-field angle ($θ_{B}$). We derive the power spectrum of the intensity and $θ_{B}$ along the ridge crest. Our analyses show a complex B-field structure when observed over the whole region ($\sim10$ pc), however, at smaller scales ($\sim1$ pc), $θ_{B}$ varies coherently along the filaments. The observed power spectrum of $θ_{B}$ can be well represented with a power law function with a slope $-1.33\pm0.23$, which is $\sim20\%$ shallower than that of $I$. This result is compatible with the properties of simulated filaments and may indicate the processes at play in the formation of filaments. $θ_{B}$ rotates from being mostly perpendicular to the filament crests to mostly parallel as they merge with the hubs. This variation of $θ_{B}$ may be tracing local velocity flows of matter in-falling onto the hubs. Our analysis suggests a variation of the energy balance along the crests of these filaments, from magnetically critical/supercritical at their far ends to magnetically subcritical near the hubs. We detect an increase of $PF$ towards the high-column density star cluster-forming hubs that may result from the increase of grain alignment efficiency due to stellar radiation from the newborn stars.

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