J/MNRAS/477/1993 NGC 1893 stars LSR velocities (Lim+, 2018)
Kinematic evidence for feedback-driven star formation in NGC 1893.
Lim B., Sung H., Bessell M.S., Lee S., Lee J.J., Oh H., Hwang N.,
Park B.-G., Hur H., Hong K., Park S.
<Mon. Not. R. Astron. Soc., 477, 1993-2003 (2018)>
=2018MNRAS.477.1993L 2018MNRAS.477.1993L (SIMBAD/NED BibCode)
ADC_Keywords: H II regions ; Radial velocities
Keywords: stars: formation - stars: kinematics and dynamics; H II regions -
ISM: kinematics and dynamics -
open clusters and associations: individual: NGC 1893
Abstract:
OB associations are the prevailing star-forming sites in the Galaxy.
Up to now, the process of how OB associations were formed remained a
mystery. A possible process is self-regulating star formation driven
by feedback from massive stars. However, although a number of
observational studies uncovered various signposts of feedback-driven
star formation, the effectiveness of such feedback has been
questioned. Stellar and gas kinematics is a promising tool to capture
the relative motion of newborn stars and gas away from ionizing
sources. We present high-resolution spectroscopy of stars and gas in
the young open cluster NGC 1893. Our findings show that newborn stars
and the tadpole nebula Sim 130 are moving away from the central
cluster containing two O-type stars, and that the time-scale of
sequential star formation is about 1Myr within a 9pc distance. The
newborn stars formed by feedback from massive stars account for at
least 18 per cent of the total stellar population in the cluster,
suggesting that this process can play an important role in the
formation of OB associations. These results support the
self-regulating star formation model.
Description:
We observed a 15.8arcminx15.8arcmin region of NGC 1893 using the FLI
PL16803 CCD camera on the 1-m telescope at Deokheung Optical Astronomy
Observatory in Korea on 2016 November 28. The narrow band Hβ,
[OIII] λ5007, and [SII] λ6712 filters were used to
study the nebulosity of ionized gas across the cluster.
We observed a 18arcminx18arcmin region of NGC 1893 on 2009 January 19
using this camera with the broad-band UBVI and narrow band Hα
filters. Image pre-processing and photometry of stars are described in
our previous work in detail (Lim et al., 2014MNRAS.443..454L 2014MNRAS.443..454L, Cat.
J/MNRAS/443/454).
Queue scheduled observations of 183 target stars out of 906 cluster
members were carried out on 2016 January 26, 27, 28, and 31 with the
multi-object high-resolution spectrograph Hectochelle attached to the
6.5-m telescope of the MMT observatory.
The Immersion GRating INfrared Spectrograph (IGRINS) simultaneously
obtained the near-infrared H- and K-band spectra with a high spectral
resolution of R∼45000. This spectrograph was operated with the 2.7-m
Harlan J. Smith Telescope at McDonald Observatory of the University of
Texas at Austin until the first half year of 2016. Pilot observations
of three slit positions on the head of the tadpole nebula Sim 130 was
made on 2016 March 2. In the fall of 2016, IGRINS was installed on the
4.3-m Discovery Channel Telescope at Lowell Observatory. We observed
six slit positions on the head of Sim 129 and eight positions on that
of Sim 130 on 2016 November 18 and 19, respectively.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 55 1571 Radial velocities of gas measured from
H2 1-0 S(1) emission line and the forbidden
line [NII]λ6584
table3.dat 67 90 Radial velocities of stars
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See also:
J/MNRAS/443/454 : UBVIHα photometry in NGC 1893 (Lim+, 2014)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Inst Instrument (IGRINS or Hectochelle)
15- 16 I2 h RAh Right ascension (J2000)
18- 19 I2 min RAm Right ascension (J2000)
21- 25 F5.2 s RAs Right ascension (J2000)
27 A1 --- DE- Declination sign (J2000)
28- 29 I2 deg DEd Declination (J2000)
31- 32 I2 arcmin DEm Declination (J2000)
34- 37 F4.1 arcsec DEs Declination (J2000)
39- 43 F5.1 km/s RVlsr LSR radial velocity
45- 47 F3.1 km/s e_RVlsr rms uncertainty on RVlsr
49- 55 A7 --- Rem Remarks
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Inst Instrument (BOES or Hectochelle) (1)
13- 16 I4 --- ID ID from Lim et al. (2014,
Cat. J/MNRAS/443/454)
18- 19 I2 h RAh Right ascension (J2000)
21- 22 I2 min RAm Right ascension (J2000)
24- 28 F5.2 s RAs Right ascension (J2000)
30 A1 --- DE- Declination sign (J2000)
31- 32 I2 deg DEd Declination (J2000)
34- 35 I2 arcmin DEm Declination (J2000)
37- 40 F4.1 arcsec DEs Declination (J2000)
42- 46 F5.1 km/s RVlsr LSR radial velocity
48- 51 F4.1 km/s e_RVlsr rms uncertainty on RVlsr
53- 67 A15 --- Rem Remarks (2)
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Note (1): For Inst=Hectochelle, radial velocities of stars with r-statistics
larger than 6.
Note (2): Other name or
SB2 = Double-lined spectroscopic binary
SB2? = Double-lined spectroscopic binary candidate
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 03-Jun-2021