KINEMATICS OF THE AMMONIA DISK AROUND THE PROTOSTAR NGC 1333 IRAS 4A2

Journal Article · Mon Nov 01 04:00:00 EDT 2010 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/723/1/L34· OSTI ID:21452724

Choi, Minho; Kang, Miju ^[1]; Tatematsu, Ken'ichi ^[2]

---

1. International Center for Astrophysics, Korea Astronomy and Space Science Institute, Daedeokdaero 776, Yuseong, Daejeon 305-348 (Korea, Republic of)
2. National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)

The NGC 1333 IRAS 4A protobinary was observed in the ammonia (2, 2) and (3, 3) lines with an angular resolution of 0.3 arcsec. The ammonia emission source of IRAS 4A2 is elongated in the direction perpendicular to the bipolar jet and has a size of 0.55 arcsec or 130 AU. This emission structure was interpreted as a circumstellar disk around the IRAS 4A2 protostar, and the rotation kinematics of the disk was investigated by making a position-velocity diagram along the major axis. Assuming a Keplerian rotation, the disk has a rotation velocity of 1.8 km s{sup -1} at a radius of 20 AU, which implies a central object of about 0.08 solar masses. The collapse age of the protostar is about 50,000 yr. The mass, accretion rate, and age are consistent with what are expected from the standard theory of low-mass star formation. If IRAS 4A2 grows at this rate, it may become a star similar to the Sun.

• OSTI ID: 21452724
• Journal Information: Astrophysical Journal Letters, Journal Name: Astrophysical Journal Letters Journal Issue: 1 Vol. 723; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ACCRETION DISKS
AMMONIA
EMISSION
HYDRIDES
HYDROGEN COMPOUNDS
MAIN SEQUENCE STARS
MOTION
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
ROTATION
STARS
SUN