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arXiv · 1007.4385

Astrometry of H$_{2}$O Masers in Nearby Star-Forming Regions with VERA --- IV. L1448C

Tomoya Hirota·Mareki Honma·Hiroshi Imai·Kazuyoshi Sunada·YuJi Ueno·Hideyuki Kobayashi·Noriyuki Kawaguchi
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Abstract

We have carried out multi-epoch VLBI observations with VERA (VLBI Exploration of Radio Astrometry) of the 22~GHz H$_{2}$O masers associated with a Class 0 protostar L1448C in the Perseus molecular cloud. The maser features trace the base of collimated bipolar jet driven by one of the infrared counter parts of L1448C named as L1448C(N) or L1448-mm A. We detected possible evidences for apparent acceleration and precession of the jet according to the three-dimensional velocity structure. Based on the phase-referencing VLBI astrometry, we have successfully detected an annual parallax of the H$_{2}$O maser in L1448C to be 4.31$\pm$0.33~milliarcseconds (mas) which corresponds to a distance of 232$\pm$18~pc from the Sun. The present result is in good agreement with that of another H$_{2}$O maser source NGC~1333 SVS13A in the Perseus molecular cloud, 235~pc. It is also consistent with the photometric distance, 220~pc. Thus, the distance to the western part of the Perseus molecular cloud complex would be constrained to be about 235~pc rather than the larger value, 300~pc, previously reported.

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Tomoya Hirota, Mareki Honma, Hiroshi Imai, Kazuyoshi Sunada, YuJi Ueno, Hideyuki Kobayashi, Noriyuki Kawaguchi. 2010-07-26. Astrometry of H$_{2}$O Masers in Nearby Star-Forming Regions with VERA --- IV. L1448C. https://doi.org/10.1093/pasj%2F63.1.1

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