scholarly journals High Resolution Observations of Molecular Gas in the Outflow of M 82

2004 ◽  
Vol 217 ◽  
pp. 314-315
Author(s):  
Fabian Walter ◽  
Axel Weiss ◽  
Nick Scoville
Keyword(s):  
High Resolution ◽  
Mechanical Energy ◽  
Opening Angle ◽  
Molecular Gas ◽  
Molecular Outflow ◽  
Outflow Velocity ◽  
Line Splitting ◽  
Total Mechanical Energy ◽  
First Time ◽  
Absorption Features

We present a high-resolution (3.6“, 70 pc) CO(1-0) mosaic of the molecular gas in M 82 covering an area of 2.5'x3.5’ (2.8 kpc x 3.9 kpc) obtained with the OVRO millimeter interferometer. The observations reveal the presence of huge amounts of molecular gas (> 70% of the total molecular mass, Mtot ≈ 1.3 × 109M⊙) outside the central 1 kpc disk. Molecular streamers are detected in and below M 82's disk out to distances from the center of ~1.7 kpc. Some of these streamers are well correlated with optical absorption features; they form the basis of some of the prominent tidal HI features around M 82. This provides evidence that the molecular gas within M 82's optical disk is disrupted by the interaction with M 81. Molecular gas is found in M 82's outflow/halo, reaching distances up to 1.2 kpc below the plane; CO line-splitting has been detected for the first time in the outflow. The maximum outflow velocity is ~ 230 km s−1; we derive an opening angle of ~ 55° for the molecular outflow cone. The total amount of gas in the outflow is > 3 × 108 M⊙ and its kinetic energy is of order 1055 erg, about one percent of the estimated total mechanical energy input of M 82's starburst. Our study implies that extreme starburst environments can move significant amounts of molecular gas in to a galaxy's halo (and even to the intergalactic medium).

scholarly journals The Molecular Outflow and CO Bullets in HH111

1997 ◽  
Vol 182 ◽  
pp. 141-152 ◽  
Author(s):  
J. Cernicharo ◽  
R. Neri ◽  
Bo Reipurth
Keyword(s):  
High Velocity ◽  
Angular Resolution ◽  
High Angular Resolution ◽  
Molecular Gas ◽  
Kinetic Temperature ◽  
Low Velocity ◽  
Molecular Outflow ◽  
Hh Objects ◽  
Physical Phenomena ◽  
First Time

We present high angular resolution observations of the molecular outflow associated with the optical jet and HH objects of the HH111 system. Interferometric observations in the CO J =2–1 and J =1–0 lines of the high velocity bullets associated with HH111 are presented for the first time. The molecular gas in these high velocity clumps has a moderate kinetic temperature and a mass of a few 10–4 M⊙ per bullet. We favor the view that HH jets and CO bullets, which represent different manifestations of the same physical phenomena, are driving the low-velocity molecular outflow.

scholarly journals Enhanced UV radiation and dense clumps in the molecular outflow of Mrk 231

2020 ◽  
Vol 633 ◽  
pp. A163 ◽  
Author(s):  
Claudia Cicone ◽  
Roberto Maiolino ◽  
Susanne Aalto ◽  
Sebastien Muller ◽  
Chiara Feruglio
Keyword(s):  
Gas Phase ◽  
Uv Radiation ◽  
Molecular Clouds ◽  
Line Emission ◽  
Molecular Gas ◽  
Spectral Features ◽  
Giant Molecular Clouds ◽  
Dense Phase ◽  
Molecular Outflow ◽  
First Time

We present interferometric observations of the CN(1–0) line emission in Mrk 231 and combine them with previous observations of CO and other H2 gas tracers to study the physical properties of the massive molecular outflow. We find a strong boost of the CN/CO(1–0) line luminosity ratio in the outflow of Mrk 231, which is unprecedented compared to any other known Galactic or extragalactic astronomical source. For the dense gas phase in the outflow traced by the HCN and CN emissions, we infer XCN ≡ [CN]/[H2]> XHCN by at least a factor of three, with H2 gas densities of nH2 ∼ 105−6 cm−3. In addition, we resolve for the first time narrow spectral features in the HCN(1–0) and HCO+(1–0) high-velocity line wings tracing the dense phase of the outflow. The velocity dispersions of these spectral features, σv ∼ 7−20 km s−1, are consistent with those of massive extragalactic giant molecular clouds detected in nearby starburst nuclei. The H2 gas masses inferred from the HCN data are quite high, Mmol ∼ 0.3−5 × 108 M⊙. Our results suggest that massive complexes of denser molecular gas survive embedded into the more diffuse H2 phase of the outflow, and that the chemistry of these outflowing dense clouds is strongly affected by UV radiation.

scholarly journals Evidence of galaxy interaction in the narrow-line Seyfert 1 galaxy IRAS 17020+4544 seen by NOEMA

2020 ◽  
Vol 501 (1) ◽  
pp. 219-228
Author(s):  
Q Salomé ◽  
A L Longinotti ◽  
Y Krongold ◽  
C Feruglio ◽  
V Chavushyan ◽  
...  
Keyword(s):  
Gas Content ◽  
Host Galaxy ◽  
Molecular Gas ◽  
Narrow Line ◽  
Nuclear Region ◽  
X Ray ◽  
Molecular Outflow ◽  
Galaxy Interaction ◽  
Massive Outflow ◽  
First Time

ABSTRACT The narrow-line Seyfert 1 galaxy IRAS 17020+4544 is one of the few sources where both an X-ray ultrafast outflow and a molecular outflow were observed to be consistent with energy conservation. However, IRAS 17020+4544 is less massive and has a much more modest active galactic nucleus (AGN) luminosity than the other examples. Using recent CO(1–0) observations with the NOrthern Extended Millimeter Array, we characterized the molecular gas content of the host galaxy for the first time. We found that the molecular gas is distributed into an apparent central disc of 1.1 × 109 M⊙, and a northern extension located up to 8 kpc from the centre with a molecular gas mass $M_{\mathrm{ H}_2}\sim 10^8\, \mathrm{ M}_\odot$. The molecular gas mass and the CO dynamics in the northern extension reveal that IRAS 17020+4544 is not a standard spiral galaxy, instead it is interacting with a dwarf object corresponding to the northern extension. This interaction possibly triggers the high accretion rate on to the supermassive black hole. Within the main galaxy, which hosts the AGN, a simple analytical model predicts that the molecular gas may lie in a ring, with less molecular gas in the nuclear region. Such distribution may be the result of the AGN activity that removes or photodissociates the molecular gas in the nuclear region (AGN feedback). Finally, we have detected a molecular outflow of mass $M_{\mathrm{ H}_2}=(0.7\!-\!1.2)\times 10^7\, \mathrm{ M}_\odot$ in projection at the location of the northern galaxy, with a similar velocity to that of the massive outflow reported in previous millimetre data obtained by the Large Millimeter Telescope.

High resolution emission spectrum of H2 between 78 and 118 nm

1984 ◽  
Vol 62 (12) ◽  
pp. 1686-1705 ◽  
Author(s):  
Jean-Yves Roncin ◽  
Françoise Launay ◽  
Michel Larzilliere
Keyword(s):  
High Resolution ◽  
Emission Spectrum ◽  
Appreciable Amount ◽  
Molecular Constants ◽  
Strong Emission ◽  
Reported Data ◽  
Quantum Defect Theory ◽  
First Time ◽  
Line Positions ◽  
Absorption Features

The complete high resolution emission spectrum of molecular hydrogen is obtained for the first time in the range 78–118 nm. A uniform set of data is derived from accurate line positions of the (unperturbed) Q branches of the C, D, D′, and [Formula: see text] transitions. Molecular constants fitted for both the ground state and the excited states of symmetry [Formula: see text] are obtained. For the latter case, they are compared with ab initio and multichannel quantum defect theory (MQDT) calculations. Self-absorption features indicate the production, in an appreciable amount, of H2(ν″ = 1) in the discharge. The reported data were not available to laser physicists and also astrophysicists who have observed strong emission lines of H2 from the atmospheres of Jupiter and Saturn.

scholarly journals Spatio-kinematical model of the collimated molecular outflow in the water-fountain nebula IRAS 16342–3814

2019 ◽  
Vol 629 ◽  
pp. A8 ◽  
Author(s):  
D. Tafoya ◽  
G. Orosz ◽  
W. H. T. Vlemmings ◽  
R. Sahai ◽  
A. F. Pérez-Sánchez
Keyword(s):  
Velocity Field ◽  
High Velocity ◽  
Three Dimensional ◽  
Opening Angle ◽  
Molecular Gas ◽  
Lower Velocity ◽  
Maser Emission ◽  
Molecular Outflow ◽  
Kinematical Model ◽  
Water Maser

Context. Water-fountain nebulae are asymptotic giant branch (AGB) and post-AGB objects that exhibit high-velocity outflows traced by water-maser emission. Their study is important for understanding the interaction between collimated jets and the circumstellar material that leads to the formation of bipolar and/or multi-polar morphologies in evolved stars. Aims. The aim of this paper is to describe the three-dimensional morphology and kinematics of the molecular gas of the water-fountain nebula IRAS 16342−3814. Methods. Data was retrieved from the ALMA archive for analysis using a simple spatio-kinematical model. The software SHAPE was employed to construct a three-dimensional, spatio-kinematical model of the molecular gas in IRAS 16342−3814, and to then reproduce the intensity distribution and position-velocity diagram of the CO emission from the ALMA observations to derive the morphology and velocity field of the gas. Data from CO(J = 1 → 0) supported the physical interpretation of the model. Results. A spatio-kinematical model that includes a high-velocity collimated outflow embedded within material expanding at relatively lower velocity reproduces the images and position-velocity diagrams from the observations. The derived morphology is in good agreement with previous results from IR and water-maser emission observations. The high-velocity collimated outflow exhibits deceleration across its length, while the velocity of the surrounding component increases with distance. The morphology of the emitting region, the velocity field, and the mass of the gas as function of velocity are in excellent agreement with the properties predicted for a molecular outflow driven by a jet. The timescale of the molecular outflow is estimated to be ~70–100 yr. The scalar momentum carried by the outflow is much larger than it can be provided by the radiation of the central star. An oscillating pattern was found associated with the high-velocity collimated outflow. The oscillation period of the pattern is T ≈ 60–90 yr and its opening angle is θop ≈ 2°. Conclusions. The CO (J = 3 → 2) emission in IRAS 16342−3814 is interpreted in terms of a jet-driven molecular outflow expanding along an elongated region. The position-velocity diagram and the mass spectrum reveal a feature due to entrained material that is associated with the driving jet. This feature is not seen in other more evolved objects that exhibit more developed bipolar morphologies. It is likely that the jet in those objects has already disappeared since it is expected to last only for a couple hundred years. This strengthens the idea that water fountain nebulae are undergoing a very short transition during which they develop the collimated outflows that shape the circumstellar envelopes. The oscillating pattern seen in the CO high-velocity outflow is interpreted as due to precession with a relatively small opening angle. The precession period is compatible with the period of the corkscrew pattern seen at IR wavelengths. We propose that the high-velocity molecular outflow traces the underlying primary jet that produces such a pattern.

scholarly journals Bipolar molecular outflow of the very low-mass star Par-Lup3-4

2020 ◽  
Vol 640 ◽  
pp. A13
Author(s):  
A. Santamaría-Miranda ◽  
I. de Gregorio-Monsalvo ◽  
N. Huélamo ◽  
A. L. Plunkett ◽  
Á. Ribas ◽  
...  
Keyword(s):  
Spectral Energy Distribution ◽  
Spectral Energy ◽  
Molecular Gas ◽  
Mass Star ◽  
Low Mass Stars ◽  
Molecular Outflow ◽  
Outflow Rate ◽  
Low Mass ◽  
First Time ◽  
Mass Sources

Context. Very low-mass stars are known to have jets and outflows, which is indicative of a scaled-down version of low-mass star formation. However, only very few outflows in very low-mass sources are well characterized. Aims. We characterize the bipolar molecular outflow of the very low-mass star Par-Lup3-4, a 0.12 M⊙ object known to power an optical jet. Methods. We observed Par-Lup3-4 with ALMA in Bands 6 and 7, detecting both the continuum and CO molecular gas. In particular, we studied three main emission lines: CO(2–1), CO(3–2), and 13CO(3–2). Results. Our observations reveal for the first time the base of a bipolar molecular outflow in a very low-mass star, as well as a stream of material moving perpendicular to the primary outflow of this source. The primary outflow morphology is consistent with the previously determined jet orientation and disk inclination. The outflow mass is 9.5 × 10−7 M⊙, with an outflow rate of 4.3 × 10−9 M⊙ yr−1. A new fitting to the spectral energy distribution suggests that Par-Lup3-4 may be a binary system. Conclusions. We have characterized Par-Lup3-4 in detail, and its properties are consistent with those reported in other very low-mass sources. This source provides further evidence that very low-mass sources form as a scaled-down version of low-mass stars.

High-resolution CO images of the Galactic central molecular zone

2019 ◽  
Vol 71 (Supplement_1) ◽  
Author(s):  
Sekito Tokuyama ◽  
Tomoharu Oka ◽  
Shunya Takekawa ◽  
Yuhei Iwata ◽  
Shiho Tsujimoto ◽  
...  
Keyword(s):  
High Resolution ◽  
Spatial Resolution ◽  
Detailed Comparison ◽  
Molecular Gas ◽  
Data Sets ◽  
Radio Observatory ◽  
James Clerk Maxwell ◽  
The Galaxy ◽  
Special Area ◽  
First Time

Abstract We performed Nyquist-sampled mapping observations of the central molecular zone of our Galaxy in the J = 1–0 lines of CO, 13CO, and C18O using the 45 m telescope at the Nobeyama Radio Observatory. The newly obtained data sets were an improvement by a factor of four in spatial resolution of the CO data previously obtained with the same telescope 22 years ago, providing the highest angular resolution CO atlas of this special area of the Galaxy. The data cover the area: −0${^{\circ}_{.}}$8 ≤ l ≤ +1${^{\circ}_{.}}$4 and −0${^{\circ}_{.}}$35 ≤ b ≤ +0${^{\circ}_{.}}$35 with a 15″ beamwidth. Total intensity ratios for CO J = 3–2/J = 1–0, 13CO/CO J = 1–0 and C18O/13CO J = 1–0, are 0.70 ± 0.06, 0.12 ± 0.01, and 0.14 ± 0.01, respectively. The high-resolution CO images show the fine structure of the molecular gas and enable us to identify a number of compact clouds with broad velocity widths, i.e., high-velocity compact clouds. We conducted a detailed comparison of our CO J = 1–0 data with the CO J = 3–2 data obtained with the James Clerk Maxwell Telescope to derive the distribution and kinematics of the highly excited gas. Three, out of four, of the previously identified high CO J = 3–2/J = 1–0 ratio areas at l = +1${^{\circ}_{.}}$3, 0${^{\circ}_{.}}$0, and −0${^{\circ}_{.}}$4 were confirmed with a higher spatial resolution. In addition to these, we identified several very compact, high CO J = 3–2/J = 1–0 spots with broad velocity widths for the first time. These are candidates for accelerated gas in the vicinity of invisible, point-like massive objects.

scholarly journals High-Resolution Molecular Line Observations of the Core and Outflow in Orion B

1989 ◽  
Vol 120 ◽  
pp. 339-339
Author(s):  
J.S. Richer ◽  
R.E. Hills ◽  
R. Padman
Keyword(s):  
High Resolution ◽  
Central Axis ◽  
Molecular Gas ◽  
Kinetic Temperature ◽  
Excitation Temperature ◽  
Molecular Line ◽  
Core Mass ◽  
The Core ◽  
Molecular Outflow ◽  
Cloud Core

High-resolution CO J → 1 → 2 observations of the Orion B molecular outflow show that the outflow is unipolar, and that there is evidence of acceleration of molecular gas at up to 0.5pc from the driving star. The highest-velocity material, as well as being furthest from the source, seems to lie close to the central axis of the flow, and is presumably being accelerated by entrainment in the flow or jet emanating from the star. We have also mapped the HCO+J = 3 → 2 emission at 19-arcsec resolution. We derive an excitation temperature of around 25 K in the cloud core, and a core mass of about 75 M⊙, this estimate is in accord with a model in which the core has a kinetic temperature of 30-50 K, with no molecular depletion on to grains. This is in contrast to the recent suggestion that the core contains cold isothermal protostars.

scholarly journals M 31's Molecular Arms at All Scales to Below 10 pc

2001 ◽  
Vol 205 ◽  
pp. 352-355 ◽  
Author(s):  
N. Neininger ◽  
Ch. Nieten ◽  
M. Guélin ◽  
H. Ungerechts ◽  
R. Lucas ◽  
...  
Keyword(s):  
High Resolution ◽  
Angular Resolution ◽  
Molecular Gas ◽  
Data Set ◽  
Unique Data ◽  
Small Scales ◽  
M 31 ◽  
Star Formation Regions ◽  
The Individual ◽  
First Time

I present a unique data set for the study of molecular gas in galaxies: a complete, high-resolution survey of the CO in M 31 and additional local studies. The fully sampled survey has an angular resolution of 23 FWHM and the interferometric data attain the pc-scale with sub-arcsecond resolution. For the first time it is now possible to study large and small scales in conjunction. Thus we are able to derive the global structure and study the links down to the individual cloud complexes and star formation regions.

Ground state molecular parameters of phosphine, PH3, from the simultaneous analysis of the high-resolution infrared, microwave and submillimeterwave spectra

1985 ◽  
Vol 50 (11) ◽  
pp. 2480-2492 ◽  
Author(s):  
Soňa Přádná ◽  
Dušan Papoušek ◽  
Jyrki Kauppinen ◽  
Sergei P. Belov ◽  
Andrei F. Krupnov ◽  
...  
Keyword(s):  
Fourier Transform ◽  
High Resolution ◽  
Ground State ◽  
Unitary Transformation ◽  
Point Of View ◽  
Acoustic Detection ◽  
Molecular Parameters ◽  
Microwave Spectrometer ◽  
Fourier Transform Spectra ◽  
First Time

Fourier transform spectra of the ν2 band of PH3 have been remeasured with 0.0045 cm-1 resolution. Ground state combination differences from these data have been fitted simultaneously with the microwave and submillimeterwave data to determine the ground state spectroscopical parameters of PH3 including the parameters of the Δk = ± 3n interactions. The correlation between the latter parameters has been discussed from the point of view of the existence of two equivalent effective rotational operators which are related by a unitary transformation. The ΔJ = 0, +1, ΔK = 0 (A1 ↔ A2, E ↔ E) rotational transitions in the ν2 and ν4 states have been measured for the first time by using a microwave spectrometer and a radiofrequency spectrometer with acoustic detection.

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