NGC 346 in The Small Magellanic Cloud. IV. Triggered Star Formation in the H<scp>ii</scp>Region N66

Gouliermis, D. A.; Chu, You‐Hua; Henning, Thomas; Brandner, W.; Gruendl, R. A.; Hennekemper, Eva; Hormuth, F.

doi:10.1086/592393

Cited by 39 publications

(44 citation statements)

References 66 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Note that kinematic methods usually underestimate the ages of associations (Brown et al 1997). Additionally, the bubble can also be formed from the strong winds of the massive stars of the first generation (see Gouliermis et al 2008). However, the age derived for CepOB2 was confirmed by Sicilia-Aguilar et al (2004).…”

Section: The Cep Ob2 Associationmentioning

confidence: 98%

Massive binaries in the Cepheus OB2/3 region

Peter

Feldt

Henning

et al. 2012

A&A

View full text Add to dashboard Cite

Context. Two different formation scenarios for stars of masses larger than 10 M exist. Although simulations within both scenarios are capable of producing stars up to the highest observed masses, the relevance of the two formation scenarios for massive star-formation is not yet clear. Aims. We aim to detect companions to massive stars to constrain the binary parameters of the multiple systems. These findings will help to constrain the formation of massive stars. Methods. We performed z -band observations of massive and intermediate-mass stars in the Cep OB2/3 associations with the Lucky imaging camera AstraLux on the 2.2 m telescope of the Calar Alto observatory. The analysis aimed at detecting binary systems with separations out to 2. 2 (∼1700 AU), the inner limit depending on the contrast. The maximum contrast of 7 mag in z (corresponding to a mass contrast of 17:1 versus an O9V primary) requires a minimum separation of 0. 7 (∼550 AU). Results. We found 28 new companions for our sample of 148 intermediate-mass and massive stars in Cep OB2/3. The companion star fraction of the massive stars is 0.7; about 50% of the systems are triples. The mass function of the companions to the massive stars is strongly top-heavy. We found that the sample parameters closely agreed with those found in the Orion Trapezium cluster. Conclusions. The multiplicity of massive stars seems to be significantly higher than that of intermediate-mass stars, independently of the environment. The comparison of our findings with the theories of massive star-formation favor the formation of massive stars by the fragmentation of proto-stellar cores combined with competitive accretion.

show abstract

Section: The Cep Ob2 Associationmentioning

confidence: 98%

Massive binaries in the Cepheus OB2/3 region

Peter

Feldt

Henning

et al. 2012

A&A

View full text Add to dashboard Cite

show abstract

“…NGC 346 is a young cluster of age about 3 Myr, and it contains several O stars among which are O3-O5 stars (Walborn & Blades 1986;Evans et al 2006, and references therein). Star formation has occurred in this region for much longer, up to 10 Myr, and must be ongoing as N 66 contains numerous pre-main-sequence objects (Sabbi et al 2007;Simon et al 2007;Hennekemper et al 2008;Gouliermis et al 2006Gouliermis et al , 2008Gouliermis et al , 2009) as well as a supernova remnant (Ye et al 1991). Although the nebula shows considerable structure, there are no strong peaks in either line or continuum emission from gas and dust.…”

Section: Smcmentioning

confidence: 99%

C⁺emission from the Magellanic Clouds

Israel

Maloney

2011

A&A

View full text Add to dashboard Cite

Context. We study the λ 158 μm [C II] fine-structure line emission from star-forming regions as a function of metallicity. Aims. We have measured and mapped the [C II] emission from the very bright HII region complexes N 11 in the LMC and N 66 in the SMC; as well as the SMC H II regions N 25, N 27, N 83/N 84, and N 88 with the FIFI instrument on the Kuiper Airborne Observatory. Methods. In both LMC and SMC, the ratio of [C II] line to CO line and to the far-infrared continuum emission is much higher than seen almost anywhere else, including Milky Way star-forming regions, and whole galaxies. Results. In the low metallicity, low dust-abundance environment of the LMC and the SMC UV mean free path lengths are much greater than those in the higher-metallicity Milky Way. The increased photoelectric heating efficiencies cause significantly greater relative [C II] line emission strengths. At the same time, similar decreases in PAH abundances have the opposite effect by diminishing photoelectric heating rates. Consequently, in low-metallicity environments relative [C II] strengths are high but exhibit little further dependence on actual metallicity. Relative [C II] strengths are slightly higher in the LMC than in the SMC which has both lower dust and lower PAH abundances.

show abstract

“…According to Rubio et al (2000), massive star formation could be taking place in dense H 2 knots associated with molecular clumps. According to Gouliermis et al (2008) PMS clusters could be candidate YSOs. These results strengthen our assumption that N88A-cl could contain YSOs.…”

Section: H 2 Emissionmentioning

confidence: 99%

VLT/NACO near-infrared imaging and spectroscopy of N88A in the SMC

Testor¹,

Lemaire

Heydari-Malayeri³

et al. 2010

A&A

View full text Add to dashboard Cite

Aims. We present near-infrared imaging and spectroscopic high spatial resolution observations of the SMC region N88 containing the bright, excited, extincted and compact H II region N88A of the size of about 1 pc. Methods. To investigate its stellar content and reddening, N88 was observed using spectroscopy and imagery in the JHKs-and L -band at a spatial resolution of ∼0.1−0.3 , using the VLT UT4 equipped with the NAOS adaptive optics system. In an attempt to establish if the origin of the infra-red (IR) excess is due to bright nebulosity, circumstellar material and/or local dust, we used Ks vs. J − K color−magnitude (CM) and JHK color−color (CC) diagrams, as well as L imagery. Results. Our IR-data reveal in the N88 area an IR-excess fraction of ≥30 per cent of the detected stars as well as an unprecedently detailed morphology of N88A. It consists of an embedded cluster of ∼3.5 (∼1 pc) in diameter of at least thirteen resolved stars superposed with an unusual bright continuum centered on a very bright star. The four brightest stars in this cluster lie red-ward of H − K ≥ 0.45 mag and could be classified as young stellar object (YSO) candidates. Four other probable YSO candidates are also detected in N88 along a north-south bow-shaped thin H 2 filament at ∼7 east of the young central bright star. This star, which we assume to be the main exciting source, could also be complex. At 0.2 east of this star, a heavily embedded core is detected in the L -band. This core with L ∼ 14 mag and L − K ≥ 4.5 mag could be a massive class I protostar candidate. The 2.12 μm H 2 image of N88A resembles a shell of a diameter of ∼3 (∼0.9 pc) centered on the bright star. This shell consists of three bright components, of which the brightest one superposes the ionization front. The line ratios of H 2 2−1 S(1) and 1−0 S(0) relative to 1−0 S(1), as well as the presence of high v lines, are indicative of photodissociation regions, rather than shocks.

show abstract

NGC 346 in The Small Magellanic Cloud. IV. Triggered Star Formation in the HiiRegion N66

Cited by 39 publications

References 66 publications

Massive binaries in the Cepheus OB2/3 region

Massive binaries in the Cepheus OB2/3 region

C⁺emission from the Magellanic Clouds

VLT/NACO near-infrared imaging and spectroscopy of N88A in the SMC

Contact Info

Product

Resources

About

NGC 346 in The Small Magellanic Cloud. IV. Triggered Star Formation in the HiiRegion N66

Cited by 39 publications

References 66 publications

Massive binaries in the Cepheus OB2/3 region

Massive binaries in the Cepheus OB2/3 region

C+emission from the Magellanic Clouds

VLT/NACO near-infrared imaging and spectroscopy of N88A in the SMC

Contact Info

Product

Resources

About

C⁺emission from the Magellanic Clouds