A First Look at BISTRO Observations of the ρ Oph-A core

We present 850 μm imaging polarimetry data of the ρ Oph-A core taken with the Submillimeter Common-User Bolometer Array-2 (SCUBA-2) and its polarimeter (POL-2) as part of our ongoing survey project, -fields In STar forming RegiOns (BISTRO). The polarization vectors are used to identify the orientation of the magnetic field projected on the plane of the sky at a resolution of 0.01 pc. We identify 10 subregions with distinct polarization fractions and angles in the 0.2 pc ρ Oph-A core; some of them can be part of a coherent magnetic field structure in the ρ Oph region. The results are consistent with previous observations of the brightest regions of ρ Oph-A, where the degrees of polarization are at a level of a few percent, but our data reveal for the first time the magnetic field structures in the fainter regions surrounding the core where the degree of polarization is much higher (>5%). A comparison with previous near-infrared polarimetric data shows that there are several magnetic field components that are consistent at near-infrared and submillimeter wavelengths. Using the Davis–Chandrasekhar–Fermi method, we also derive magnetic field strengths in several subcore regions, which range from approximately 0.2 to 5 mG. We also find a correlation between the magnetic field orientations projected on the sky and the core centroid velocity components.

Lei Zhu | A. Scaife | P. Koch | A. Whitworth | N. Peretto | G. Fuller | P. Andre' | H. Chen | T. Nakagawa | T. Onaka | M. Tamura | Sang-Sung Lee | D. Byun | D. Johnstone | P. Bastien | Jongsoo Kim | G. Savini | J. Francesco | B. Matthews | Di Li | P. Friberg | M. Seta | J. Kwon | T. Nagata | Tsuyoshi Inoue | W. Chen | K. Kawabata | S. Eyres | S. Falle | M. Griffin | W. Holland | J. Greaves | G. Moriarty-Schieven | T. Hasegawa | D. Ward-Thompson | J. Hatchell | A. Chrysostomou | J. Fiege | R. Friesen | S. Graves | M. Houde | J. Kirk | J. Richer | K. Lacaille | C. Dowell | A. Kataoka | R. Rao | M. Rawlings | H. Parsons | Jia‐Wei Wang | L. Qian | K. Qiu | T. Ching | Jinghua Yuan | A. Rigby | Jianjun Zhou | Da-lei Li | Miju Kang | Il-Gyo Jeong | H. Nakanishi | Jeong-Eun Lee | Kee-Tae Kim | Hongchi Wang | Tie Liu | Ji-hyun Kang | S. Inutsuka | F. Kemper | Minho Choi | Sung-ju Kang | Jungyeon Cho | H. Yoo | D. Berry | T. Pyo | F. Nakamura | S. Loo | D. Arzoumanian | Guoyin Zhang | Junhao Liu | Y. Doi | Chuan-Peng Zhang | Hua-b. Li | Sheng-Yuan Liu | S. Lai | A. Soam | C. Lee | Ya-Wen Tang | Gwanjeong Kim | S. Mairs | Shinyoung Kim | K. Pattle | W. Kwon | E. Chung | A. Pon | S. Hayashi | M. Matsumura | S. Sadavoy | K. Tomisaka | Y. Tsukamoto | Hsi-Wei Yen | N. Ohashi | K. Iwasaki | Yusuke Aso | H. Shinnaga | S. Coudé | E. Drabek-Maunder | T. Gledhill | Mi-Ryang Kim | R. Furuya | C. Eswaraiah | K. Kim | A. Lyo | B. Retter | Mike Chen | Thiem C. Hoang | T. Zenko | Masato I. N. Kobayashi | E. Franzmann | Hong-Li Liu | Q. Gu | J. Robitaille | Yoshihiro Kanamori | H. Saito | T. Inoue | S. Lai | Hongli Liu | Chuan-peng Zhang | W. Chen | Ya-wen Tang | P. Andre'

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