Subarcsecond resolution observations of warm water toward three deeply embedded low-mass protostars

Persson, M. V.; Jørgensen, J. K.; Dishoeck, E. F. van

doi:10.1051/0004-6361/201117917

Cited by 71 publications

(138 citation statements)

References 61 publications

Supporting

Mentioning

122

Contrasting

Order By: Relevance

“…Gusdorf et al 2008ab). Interestingly, the H 18 2 O emission imaged at PdBI by Persson et al (2012) and distributed along the direction of the blueshifted outflow, is emitting in the +1,+9 km s −1 range, suggesting that H 18 2 O also traces the outflow cavities. In summary, the low-velocity emission traces a cavity opened by the fast jet, as predicted by MHD disk wind models (Cabrit et al 1999).…”

Section: The Role Of So Emission: Jets and Cavitiesmentioning

confidence: 98%

“…5 The V LSR of IRAS2A as given in the literature lies between +7.0 km s −1 and +7.7 km s −1 (e.g. Persson et al 2012, and references therein); we adopt +6.5 km s −1 , according to CALYPSO measurements of high-excitation (∼200 K) hot-core tracers, Maret et al (2014). The jet kinematical age, derived from the farthest SiO emission, is 88 years.…”

Section: Different Jets From a Proto-binary Systemmentioning

confidence: 99%

“…SiO, CH 3 OH), revealing two perpendicular outflows, directed NE-SW (PA 25 • ; hereafter called N-S for sake of clarity) and SE-NW (PA 105 • ; hereafter E-W), both originating to within a few arcseconds from IRAS2A (e.g. Bachiller et al 1998;Knee & Sandell 2000;Jørgensen et al 2004aJørgensen et al ,b, 2009Wakelam et al 2005;Persson et al 2012;Plunkett et al 2013). These outflows seem intrinsically different, the E-W outflow being more collimated and chemically richer than the N-S one, supporting the possibility that IRAS2A is an unresolved proto-binary.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

First results from the CALYPSO IRAM-PdBI survey

Codella

Maury

Gueth

et al. 2014

A&A

View full text Add to dashboard Cite

Context. The earliest evolutionary stages of low-mass protostars are characterised by hot and fast jets which remove angular momentum from the circumstellar disk, thus allowing mass accretion onto the central object. However, the launch mechanism is still being debated. Aims. We would like to exploit high-angular (∼0. 8) resolution and high-sensitivity images to investigate the origin of protostellar jets using typical molecular tracers of shocked regions, such as SiO and SO. Methods. We mapped the inner 22 of the NGC 1333-IRAS2A protostar in SiO(5-4), SO(6 5 -5 4 ), and the continuum emission at 1.4 mm using the IRAM Plateau de Bure Interferometer in the framework of the CALYPSO IRAM large program. Results. For the first time, we disentangle the NGC 1333-IRAS2A Class 0 object into a proto-binary system revealing two protostars (MM1, MM2) separated by ∼560 AU, each of them driving their own jet, while past work considered a single protostar with a quadrupolar outflow. We reveal (i) a clumpy, fast (up to |V − V LSR | ≥ 50 km s −1 ), and blueshifted jet emerging from the brightest MM1 source; and (ii) a slower redshifted jet, driven by MM2. Silicon monoxide emission is a powerful tracer of high-excitation (T kin ≥ 100 K; n H 2 ≥ 10 5 cm −3 ) jets close to the launching region. At the highest velocities, SO appears to mimic SiO tracing the jets, whereas at velocities close to the systemic one, SO is dominated by extended emission, tracing the cavity opened by the jet. Conclusions. Both jets are intrinsically monopolar, and intermittent in time. The dynamical time of the SiO clumps is ≤30-90 yr, indicating that one-sided ejections from protostars can take place on these timescales.

show abstract

Section: The Role Of So Emission: Jets and Cavitiesmentioning

confidence: 98%

Section: Different Jets From a Proto-binary Systemmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

First results from the CALYPSO IRAM-PdBI survey

Codella

Maury

Gueth

et al. 2014

A&A

View full text Add to dashboard Cite

show abstract

“…The D/H ratio in water remained for a long time very poorly known since the study of water was based on observations suffering from dilution in the large beams of the Infrared Space Observatory (ISO), the Submillimeter Wave Astronomy Satellite (SWAS) and the ODIN satellite as well as from large opacities. The only way to study water from the ground was to use the H 18 2 O transition available with some telescopes at 203 GHz (Jacq et al 1988;van der Tak et al 2006;Persson et al 2012Persson et al , 2013. With the help of this line, the water deuterium fractionation was previously estimated in the high-mass star-forming region G34 by Jacq et al (1990), Gensheimer et al (1996), and .…”

Section: Comparison With Previous Studiesmentioning

confidence: 99%

Water deuterium fractionation in the high-mass star-forming region G34.26+0.15 based on Herschel/HIFI data

Coutens

Vastel

Hincelin

et al. 2014

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

Understanding water deuterium fractionation is important for constraining the mechanisms of water formation in interstellar clouds. Observations of HDO and H 18 2 O transitions were carried out towards the high-mass star-forming region G34.26+0.15 with the HIFI instrument onboard the Herschel Space Observatory, as well as with ground-based single-dish telescopes. Ten HDO lines and three H 18 2 O lines covering a broad range of upper energy levels (22-204 K) were detected. We used a non-LTE 1D analysis to determine the HDO/H 2 O ratio as a function of radius in the envelope. Models with different water abundance distributions were considered in order to reproduce the observed line profiles. The HDO/H 2 O ratio is found to be lower in the hot core (∼3.5 × 10 −4 -7.5 × 10 −4 ) than in the colder envelope (∼1.0 × 10 −3 -2.2 × 10 −3 ). This is the first time that a radial variation of the HDO/H 2 O ratio has been found to occur in a high-mass source. The chemical evolution of this source was modeled as a function of its radius and the observations are relatively well reproduced. The comparison between the chemical model and the observations leads to an age of ∼10 5 years after the infrared dark cloud stage.

show abstract

“…The notation IRAM refers to the single-dish 30 m-telescope. The star ( * ) shows that the modeling of the water lines was not carried out in the study quoted in Col. 2, but come, as explained in the text, from the following papers: Jørgensen & van Dishoeck (2010a); Persson et al (2012); Taquet et al (2013a); Mottram et al (2013). (3) This column describes the type of modeling used to determine the HDO/H 2 O ratio: 0D or 1D structure and LTE or non-LTE analysis.…”

Section: Sourcementioning

confidence: 99%

Deuterated water in the solar-type protostars NGC 1333 IRAS 4A and IRAS 4B

Coutens

Vastel

Cabrit

et al. 2013

A&A

Self Cite

View full text Add to dashboard Cite

Context. The measure of the water deuterium fractionation is a relevant tool for understanding mechanisms of water formation and evolution from the prestellar phase to the formation of planets and comets. Aims. The aim of this paper is to study deuterated water in the solar-type protostars NGC 1333 IRAS 4A and IRAS 4B, to compare their HDO abundance distributions with other star-forming regions, and to constrain their HDO/H 2 O abundance ratios. Methods. Using the Herschel/HIFI instrument as well as ground-based telescopes, we observed several HDO lines covering a large excitation range (E up /k = 22-168 K) towards these protostars and an outflow position. Non-local thermal equilibrium radiative transfer codes were then used to determine the HDO abundance profiles in these sources. Results. The HDO fundamental line profiles show a very broad component, tracing the molecular outflows, in addition to a narrower emission component and a narrow absorbing component. In the protostellar envelope of NGC 1333 IRAS 4A, the HDO inner (T ≥ 100 K) and outer (T < 100 K) abundances with respect to H 2 are estimated with a 3σ uncertainty at 7.5 +3.5 −3.0 × 10 −9 and 1.2 +0.4 −0.4 × 10 −11 , respectively, whereas in NGC 1333 IRAS 4B they are 1 +1.8 −0.9 × 10 −8 and 1.2 +0.6 −0.4 × 10 −10 , respectively. Similarly to the low-mass protostar IRAS 16293-2422, an absorbing outer layer with an enhanced abundance of deuterated water is required to reproduce the absorbing components seen in the fundamental lines at 465 and 894 GHz in both sources. This water-rich layer is probably extended enough to encompass the two sources, as well as parts of the outflows. In the outflows emanating from NGC 1333 IRAS 4A, the HDO column density is estimated at about (2-4) × 10 13 cm −2 , leading to an abundance of about (0.7-1.9) × 10 −9 . An HDO/H 2 O ratio between 7 × 10 −4 and 9 × 10 −2 is also derived in the outflows. In the warm inner regions of these two sources, we estimate the HDO/H 2 O ratios at about 1 × 10 −4 -4 × 10 −3 . This ratio seems higher (a few %) in the cold envelope of IRAS 4A, whose possible origin is discussed in relation to formation processes of HDO and H 2 O. Conclusions. In low-mass protostars, the HDO outer abundances range in a small interval, between ∼10 −11 and a few 10 −10 . No clear trends are found between the HDO abundance and various source parameters (L bol , L smm , L smm /L bol , T bol , L 0.6 bol /M env ). A tentative correlation is observed, however, between the ratio of the inner and outer abundances with the submillimeter luminosity.

show abstract

Subarcsecond resolution observations of warm water toward three deeply embedded low-mass protostars

Cited by 71 publications

References 61 publications

First results from the CALYPSO IRAM-PdBI survey

First results from the CALYPSO IRAM-PdBI survey

Water deuterium fractionation in the high-mass star-forming region G34.26+0.15 based on Herschel/HIFI data

Deuterated water in the solar-type protostars NGC 1333 IRAS 4A and IRAS 4B

Contact Info

Product

Resources

About