THE VLA NASCENT DISK AND MULTIPLICITY (VANDAM) SURVEY OF PERSEUS PROTOSTARS. RESOLVING THE SUB-ARCSECOND BINARY SYSTEM IN NGC 1333 IRAS2A
THE VLA NASCENT DISK AND MULTIPLICITY (VANDAM) SURVEY OF PERSEUS PROTOSTARS. RESOLVING THE SUB-ARCSECOND BINARY SYSTEM IN NGC 1333 IRAS2A
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DOI：
10.1088/0004-637x/798/1/61
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发表时间：
2014-10
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通讯作者：
J. Tobin;M. Dunham;L. Looney;Zhi-Yun Li;C. Chandler;D. Segura-Cox;S. Sadavoy;C. Melis;R. Harris;L. Pérez;K. Kratter;J. Jørgensen;A. Plunkett;C. Hull
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作者：
J. Tobin;M. Dunham;L. Looney;Zhi-Yun Li;C. Chandler;D. Segura-Cox;S. Sadavoy;C. Melis;R. Harris;L. Pérez;K. Kratter;J. Jørgensen;A. Plunkett;C. Hull
我们正在对英仙座分子云中所有已知的原恒星进行Jansky甚大阵列（VLA）Ka波段（8 mm和1 cm）和C波段（4 cm和6.4 cm）调查，在Ka波段和C波段分别提供分辨率低至100.″06和100.″35。在这里，我们提出了第一个结果，从这次调查，使我们能够检查源NGC 1333 IRAS 2A在前所未有的细节，并解决了它成为一个原双星系统，由0.“621 ± 0.”006（Au）在8毫米，1厘米，和4厘米。这两个来源（IRAS 2A VLA 1和VLA 2）可能驱动已知源自IRAS 2A的两个正交流出。较亮的IRAS 2A VLA 1在VLA数据中垂直于其流出方向延伸，反卷积大小为0. 055（13 Au），可能跟踪原恒星盘。最近报道的候选伴星（IRAS 2A MM2和MM3）在我们的VLA数据，毫米波天文学研究组合阵列（CARMA）1.3 mm数据或亚毫米阵列（SMA）850 μm数据中都没有检测到。SMA CO（J = 3 → 2）、CARMA CO（J = 2 → 1）和低分辨率CARMA CO（J = 1 → 0）观测被用来检查IRAS 2A VLA 1的外流起源和候选伴星的性质。CO（J = 3 → 2）和（J = 2 → 1）资料表明，IRAS 2A MM2与东西向外流中的一个亮CO发射点重合，而IRAS 2A MM3则位于南北向外流中。相反，IRAS 2A VLA 2位于东西流出对称点。我们认为IRAS 2A VLA 2是东西向外流的驱动源，是IRAS 2A VLA 1的真正伴星，而IRAS 2A MM 2和MM 3可能不是原恒星。
We are conducting a Jansky Very Large Array (VLA) Ka-band (8 mm and 1 cm) and C-band (4 cm and 6.4 cm) survey of all known protostars in the Perseus Molecular Cloud, providing resolution down to ∼0.″06 and ∼0.″35 in the Ka band and C band, respectively. Here we present first results from this survey that enable us to examine the source NGC 1333 IRAS2A in unprecedented detail and resolve it into a protobinary system separated by 0.″621 ± 0.″006 (∼143 AU) at 8 mm, 1 cm, and 4 cm. These two sources (IRAS2A VLA1 and VLA2) are likely driving the two orthogonal outflows known to originate from IRAS2A. The brighter source IRAS2A VLA1 is extended perpendicular to its outflow in the VLA data, with a deconvolved size of 0.″055 (∼13 AU), possibly tracing a protostellar disk. The recently reported candidate companions (IRAS2A MM2 and MM3) are not detected in either our VLA data, Combined Array for Research in Millimeter-wave Astronomy (CARMA) 1.3 mm data, or Submillimeter Array (SMA) 850 μm data. SMA CO (J = 3 → 2), CARMA CO (J = 2 → 1), and lower-resolution CARMA CO (J = 1 → 0) observations are used to examine the outflow origins and the nature of the candidate companions to IRAS2A VLA1. The CO (J = 3 → 2) and (J = 2 → 1) data show that IRAS2A MM2 is coincident with a bright CO emission spot in the east–west outflow, and IRAS2A MM3 is within the north–south outflow. In contrast, IRAS2A VLA2 lies at the east–west outflow symmetry point. We propose that IRAS2A VLA2 is the driving source of the east–west outflow and a true companion to IRAS2A VLA1, whereas IRAS2A MM2 and MM3 may not be protostellar.