Triggered star formation in a double shell near W51A

Miju Kang, John H Bieging, Craig A. Kulesa, Youngung Lee

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

We present Heinrich Hertz Telescope CO observations of the shell structure near the active star-forming complex W51A to investigate the process of star formation triggered by the expansion of an H II region. The CO observations confirm that dense molecular material has been collected along the shell detected in Spitzer IRAC images. The CO distribution shows that the shell is blown out toward a lower density region to the northwest. Total hydrogen column density around the shell is high enough to form new stars. We find two CO condensations with the same central velocity of 59 km s-1 to the east and north along the edge of the IRAC shell. We identify two young stellar objects in early evolutionary stages (Stage 0/I) within the densest molecular condensation. From the CO kinematics, we find that the H II region is currently expanding with a velocity of 3.4 km s-1, implying that the shell's expansion age is ∼ 1 Myr. This timescale is in good agreement with numerical simulations of the expansion of the H II region (Hosokawa & Inutsuka). We conclude that the star formation on the border of the shell is triggered by the expansion of the H II region.

Original languageEnglish (US)
Pages (from-to)454-463
Number of pages10
JournalAstrophysical Journal
Volume701
Issue number1
DOIs
StatePublished - 2009

Fingerprint

H II regions
star formation
shell
expansion
condensation
stars
borders
kinematics
telescopes
hydrogen
simulation
timescale

Keywords

  • Hii regions
  • Infrared: ISM
  • ISM: bubbles
  • ISM: individual (W51A)
  • ISM: kinematics and Dynamics
  • Stars: formation

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Triggered star formation in a double shell near W51A. / Kang, Miju; Bieging, John H; Kulesa, Craig A.; Lee, Youngung.

In: Astrophysical Journal, Vol. 701, No. 1, 2009, p. 454-463.

Research output: Contribution to journalArticle

Kang, Miju ; Bieging, John H ; Kulesa, Craig A. ; Lee, Youngung. / Triggered star formation in a double shell near W51A. In: Astrophysical Journal. 2009 ; Vol. 701, No. 1. pp. 454-463.
@article{c0dd3b81bde642dcaed7114ada5c4979,
title = "Triggered star formation in a double shell near W51A",
abstract = "We present Heinrich Hertz Telescope CO observations of the shell structure near the active star-forming complex W51A to investigate the process of star formation triggered by the expansion of an H II region. The CO observations confirm that dense molecular material has been collected along the shell detected in Spitzer IRAC images. The CO distribution shows that the shell is blown out toward a lower density region to the northwest. Total hydrogen column density around the shell is high enough to form new stars. We find two CO condensations with the same central velocity of 59 km s-1 to the east and north along the edge of the IRAC shell. We identify two young stellar objects in early evolutionary stages (Stage 0/I) within the densest molecular condensation. From the CO kinematics, we find that the H II region is currently expanding with a velocity of 3.4 km s-1, implying that the shell's expansion age is ∼ 1 Myr. This timescale is in good agreement with numerical simulations of the expansion of the H II region (Hosokawa & Inutsuka). We conclude that the star formation on the border of the shell is triggered by the expansion of the H II region.",
keywords = "Hii regions, Infrared: ISM, ISM: bubbles, ISM: individual (W51A), ISM: kinematics and Dynamics, Stars: formation",
author = "Miju Kang and Bieging, {John H} and Kulesa, {Craig A.} and Youngung Lee",
year = "2009",
doi = "10.1088/0004-637X/701/1/454",
language = "English (US)",
volume = "701",
pages = "454--463",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "1",

}

TY - JOUR

T1 - Triggered star formation in a double shell near W51A

AU - Kang, Miju

AU - Bieging, John H

AU - Kulesa, Craig A.

AU - Lee, Youngung

PY - 2009

Y1 - 2009

N2 - We present Heinrich Hertz Telescope CO observations of the shell structure near the active star-forming complex W51A to investigate the process of star formation triggered by the expansion of an H II region. The CO observations confirm that dense molecular material has been collected along the shell detected in Spitzer IRAC images. The CO distribution shows that the shell is blown out toward a lower density region to the northwest. Total hydrogen column density around the shell is high enough to form new stars. We find two CO condensations with the same central velocity of 59 km s-1 to the east and north along the edge of the IRAC shell. We identify two young stellar objects in early evolutionary stages (Stage 0/I) within the densest molecular condensation. From the CO kinematics, we find that the H II region is currently expanding with a velocity of 3.4 km s-1, implying that the shell's expansion age is ∼ 1 Myr. This timescale is in good agreement with numerical simulations of the expansion of the H II region (Hosokawa & Inutsuka). We conclude that the star formation on the border of the shell is triggered by the expansion of the H II region.

AB - We present Heinrich Hertz Telescope CO observations of the shell structure near the active star-forming complex W51A to investigate the process of star formation triggered by the expansion of an H II region. The CO observations confirm that dense molecular material has been collected along the shell detected in Spitzer IRAC images. The CO distribution shows that the shell is blown out toward a lower density region to the northwest. Total hydrogen column density around the shell is high enough to form new stars. We find two CO condensations with the same central velocity of 59 km s-1 to the east and north along the edge of the IRAC shell. We identify two young stellar objects in early evolutionary stages (Stage 0/I) within the densest molecular condensation. From the CO kinematics, we find that the H II region is currently expanding with a velocity of 3.4 km s-1, implying that the shell's expansion age is ∼ 1 Myr. This timescale is in good agreement with numerical simulations of the expansion of the H II region (Hosokawa & Inutsuka). We conclude that the star formation on the border of the shell is triggered by the expansion of the H II region.

KW - Hii regions

KW - Infrared: ISM

KW - ISM: bubbles

KW - ISM: individual (W51A)

KW - ISM: kinematics and Dynamics

KW - Stars: formation

UR - http://www.scopus.com/inward/record.url?scp=70449954284&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=70449954284&partnerID=8YFLogxK

U2 - 10.1088/0004-637X/701/1/454

DO - 10.1088/0004-637X/701/1/454

M3 - Article

VL - 701

SP - 454

EP - 463

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 1

ER -