Far-infrared survey of the galactic plane

ABSTRACT The Methanol MultiBeam survey (MMB) provides the most complete sample of Galactic massive young stellar objects (MYSOs) hosting 6.7 GHz class II methanol masers. We characterize the properties of these maser sources using dust emission detected by the Herschel Infrared Galactic Plane Survey (Hi-GAL) to assess their evolutionary state. Associating 731 (73 per cent) of MMB sources with compact emission at four Hi-GAL wavelengths, we derive clump properties and define the requirements of an MYSO to host a 6.7 GHz maser. The median far-infrared (FIR) mass and luminosity are 630 M⊙ and 2500 L⊙ for sources on the near side of Galactic centre and 3200 M⊙ and 10000 L⊙ for more distant sources. The median luminosity-to-mass ratio is similar for both at ∼4.2 L⊙ M⊙−1. We identify an apparent minimum 70 μm luminosity required to sustain a methanol maser of a given luminosity (with $L_{70} \propto L_{6.7}\, ^{0.6}$). The maser host clumps have higher mass and higher FIR luminosities than the general Galactic population of protostellar MYSOs. Using principal component analysis, we find 896 protostellar clumps satisfy the requirements to host a methanol maser but lack a detection in the MMB. Finding a 70 μm flux density deficiency in these objects, we favour the scenario in which these objects are evolved beyond the age where a luminous 6.7 GHz maser can be sustained. Finally, segregation by association with secondary maser species identifies evolutionary differences within the population of 6.7GHz sources.

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Discovery of the Carina Flare with NANTEN; Evidence for a Supershell That Triggered the Formation of Stars and Massive Molecular Clouds

Publications of the Astronomical Society of Japan ◽

10.1093/pasj/51.6.751 ◽

1999 ◽

Vol 51 (6) ◽

pp. 751-764 ◽

Cited By ~ 35

Author(s):

Yasuo Fukui ◽

Toshikazu Onishi ◽

Rihei Abe ◽

Akiko Kawamura ◽

Kengo Tachihara ◽

...

Keyword(s):

Kinetic Energy ◽

Molecular Clouds ◽

Galactic Plane ◽

Far Infrared ◽

Infrared Emission ◽

High Mass ◽

Stellar Winds ◽

Neutral Gas ◽

Supernova Explosions ◽

Current Kinetic

Abstract We present extensive observations of the Carina arm region in the 2.6 mm CO (J = 1−0) emission with the NANTEN telescope in Chile. The observations have revealed 120 molecular clouds which are distributed in an area of 283° < l < 293° and 2° .5 < b < 10°. Because of its vertical elongation to the galactic plane, the clouds are named the Carina flare. H I and far-infrared emission show a cavity-like distribution corresponding to the molecular clouds, and soft X-ray emission appears to fill this cavity. It is shown that the Carina flare represents a supershell at a distance of a few kpc that has been produced by about 20 supernova explosions, or equivalent stellar winds of OB stars, over the last ∼ 2×107 yr. The supershell consisting of molecular and atomic neutral gas involves a total mass and kinetic energy of ≳ 3×105M⊙ and ≳ 3×1050 erg, respectively, and the originally injected energy required is about 100-times this current kinetic energy in the shell. It is unique among supershells known previously because of the following aspects: i) it exhibits evidence for the triggered formation of intermediate-to-high-mass stars and massive molecular clouds of 102 − 104M⊙, and ii) the massive molecular clouds formed are located unusually far above the galactic plane at z ∼ 100–500 pc.

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A complete catalogue of dusty supernova remnants in the Galactic plane

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa221 ◽

2020 ◽

Vol 493 (2) ◽

pp. 2706-2744 ◽

Cited By ~ 4

Author(s):

H Chawner ◽

H L Gomez ◽

M Matsuura ◽

M W L Smith ◽

A Papageorgiou ◽

...

Keyword(s):

Supernova Remnants ◽

Galactic Plane ◽

Compact Object ◽

Far Infrared ◽

Pulsar Wind Nebulae ◽

Shock Interactions ◽

Dust Temperature ◽

Type Ia ◽

Complete Catalogue ◽

Temperature Maps

ABSTRACT We search for far-infrared (FIR) counterparts of known supernova remnants (SNRs) in the Galactic plane (360° in longitude and $b = \pm \, 1^{\circ }$) at 70–500 μm with Herschel. We detect dust signatures in 39 SNRs out of 190, made up of 13 core-collapse supernovae (CCSNe), including 4 Pulsar Wind Nebulae (PWNe), and 2 Type Ia SNe. A further 24 FIR detected SNRs have unknown types. We confirm the FIR detection of ejecta dust within G350.1−0.3, adding to the known sample of ∼ 10 SNRs containing ejecta dust. We discover dust features at the location of a radio core at the centre of G351.2+0.1, indicating FIR emission coincident with a possible Crab-like compact object, with dust temperature and mass of Td = 45.8 K and Md = 0.18 M⊙, similar to the PWN G54.1+0.3. We show that the detection rate is higher among young SNRs. We produce dust temperature maps of 11 SNRs and mass maps of those with distance estimates, finding dust at temperatures $15\, \lesssim \, T_d\, \lesssim \, 40$ K. If the dust is heated by shock interactions the shocked gas must be relatively cool and/or have a low density to explain the observed low grain temperatures.

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Ionization of the Galactic Center Arched Filaments

International Astronomical Union Colloquium ◽

10.1017/s0252921100023630 ◽

1989 ◽

Vol 120 ◽

pp. 132-133

Author(s):

R. Rubin ◽

M. Morris ◽

E.F. Erickson ◽

S. Colgan ◽

J. Simpson

Keyword(s):

Fine Structure ◽

Radio Emission ◽

Galactic Center ◽

Galactic Plane ◽

Line Emission ◽

Far Infrared ◽

Thin Filaments ◽

Ob Stars ◽

Structure Line ◽

Photoionization Model

The remarkable filament system seen in radio observations in the vicinity of the galactic center includes two thin filaments which arch away from the galactic plane (E.G. Yusef-Zadem et al 1984). The brightest part of each of these thermal structures is located at GO.10+0.02 and GO.07+0.04. Morris and Yusef-Zadem (1989) reason that photoionization by OB stars is unlikely on geometrical and morphological grounds. They suggest a magnetohydrodynamic mechanism to account for the radio emission and ionization. Erickson et al. (1968) were able to explain most of their observations of the far infrared (FIR) fine structure line emission from these locations in terms of a photoionization model.

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A Cryogenically-Cooled, Balloon-Borne Far Infrared Survey Telescope

10.1117/12.957080 ◽

1979 ◽

Author(s):

Murray F. Campbell

Keyword(s):

Far Infrared ◽

Infrared Survey

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Giant Molecular Clouds in the Galaxy: The Massachusetts-Stony Brook CO Galactic Plane Survey

Symposium - International Astronomical Union ◽

10.1017/s0074180900096297 ◽

1987 ◽

Vol 115 ◽

pp. 499-499 ◽

Cited By ~ 2

Author(s):

P. M. Solomon

Keyword(s):

Molecular Clouds ◽

Galactic Plane ◽

Far Infrared ◽

Formation Mechanisms ◽

H Ii Regions ◽

Giant Molecular Clouds ◽

Star Forming ◽

The Galaxy ◽

Two Populations ◽

Spiral Arm

The CO Galactic Plane Survey consists of 40,572 spectral line observations in the region between 1 = 8° to 90° and b = −1°.05 to +1°.05 spaced every 3 arc minutes, carried out with the FCRAO 14-m antenna. The velocity coverage from −100 to +200 km/s includes emission from all galactic radii. This high resolution survey was designed to observe and identify essentially all molecular clouds or cloud components larger than 10 parsecs in the inner galaxy. There are two populations of molecular clouds which separate according to temperature. The warm clouds are closely associated with H II regions, exhibit a non-axisymmetric galactic distribution and are a spiral arm population. The cold clouds are a disk population, are not confined to any patterns in longitude-velocity space and must be widespread in the galaxy both in and out of spiral arms. The correlation between far infrared luminosities from IRAS, and molecular masses from CO is utilized to determine a luminosity to mass ratio for the clouds. A face-on picture of the galaxy locating the warm population is presented, showing ring like or spiral arm features at R ∼ 5, 7.5 and 9 kpc. The cloud size and mass spectrum will be discussed and evidence presented showing the presence of clusters of giant molecular clouds with masses of 106 to 107 M⊙. The two populations of clouds probably have different star forming luminosity functions. The implication of the two populations for star formation mechanisms will be discussed.

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CORNISH: A 5 GHz VLA survey of the Galactic plane

Proceedings of the International Astronomical Union ◽

10.1017/s1743921310011592 ◽

2009 ◽

Vol 5 (H15) ◽

pp. 781-781

Author(s):

Cormac R. Purcell ◽

Melvin G. Hoare ◽

Keyword(s):

Star Formation ◽

Galactic Plane ◽

Radio Continuum ◽

High Mass ◽

Mass Star ◽

Multi Wavelength ◽

Region 10 ◽

5 Ghz ◽

Infrared Survey ◽

Key Questions

AbstractThe CORNISH (Co-Ordinated Radio ‘N’ Infrared Survey for High-mass star formation) project is the radio continuum part of a series of multi-wavelength surveys of the Galactic Plane that focus on the northern GLIMPSE-I region (10° < l <65°, |b| < 1°) observed by the SPITZER satellite in the mid-infrared (Churchwell et al. 2009). CORNISH has delivered a complementary 5 GHz arcsecond resolution, radio-continuum survey to address key questions in high-mass star formation as well as many other areas of astrophysics.

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