ALMA CO<i>J</i>= 6–5 observations of IRAS 16293–2422

Kristensen, L. E.; Klaassen, Pamela; Mottram, J. C.; Schmalzl, M.; Hogerheijde, M. R.

doi:10.1051/0004-6361/201220668

Cited by 36 publications

(50 citation statements)

References 19 publications

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“…At the time of writing, the scientific results obtained from this single data set include the confirmation of the detection of glycolaldehyde, a simple sugar (Jørgensen et al 2012), detection of hot H 2 18 O and constraints on the deuteration of ∼100 K water (Persson et al 2013), and the interaction of one of the outflows from source A with the surrounding medium as traced through warm CO gas (Kristensen et al 2013;Loinard et al 2012;Zapata et al 2013). Figure 13 shows the complete Band 9 spectrum of IRAS 16293-2422 B, obtained as part of this Science Verification observation.…”

Section: Science Verification: Iras 16293-2422mentioning

confidence: 96%

“…A few absorption features are also visible, caused by simple molecules like H 2 S in cold foreground gas. Note that the CO J = 6-5 line profile is heavily affected by the adopted cleaning strategy, which was optimized for weak spatially unresolved lines in source B. CO J = 6-5 emission extends over a large area (Kristensen et al 2013), and is thus not correctly cleaned. In addition, it suffers from filtering due to the absence of short baselines.…”

Section: Science Verification: Iras 16293-2422mentioning

confidence: 99%

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The ALMA Band 9 receiver

Baryshev

Hesper

Mena

et al. 2015

A&A

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Aims. We describe the design, construction, and characterization of the Band 9 heterodyne receivers (600-720 GHz) for the Atacama Large Millimeter/submillimeter Array (ALMA). First-light Band 9 data, obtained during ALMA commissioning and science verification phases, are presented as well. Methods. The ALMA Band 9 receiver units (so-called "cartridges"), which are installed in the telescope's front end, have been designed to detect and down-convert two orthogonal linear polarization components of the light collected by the ALMA antennas. The light entering the front end is refocused with a compact arrangement of mirrors, which is fully contained within the cartridge. The arrangement contains a grid to separate the polarizations and two beam splitters to combine each resulting beam with a local oscillator signal. The combined beams are fed into independent double-sideband mixers, each with a corrugated feedhorn coupling the radiation by way of a waveguide with backshort cavity into an impedance-tuned superconductor-insulator-superconductor (SIS) junction that performs the heterodyne down-conversion. Finally, the generated intermediate frequency (IF) signals are amplified by cryogenic and room-temperature HEMT amplifiers and exported to the telescope's IF back end for further processing and, finally, correlation. Results. The receivers have been constructed and tested in the laboratory and they show an excellent performance, complying with ALMA requirements. Performance statistics on all 73 Band 9 receivers are reported. Importantly, two different tunnel-barrier technologies (necessitating different tuning circuits) for the SIS junctions have been used, namely conventional AlO x barriers and the more recent high-current-density AlN barriers. On-sky characterization and tests of the performance of the Band 9 cartridges are presented using commissioning data. Continuum and line images of the low-mass protobinary IRAS 16293-2422 are presented which were obtained as part of the ALMA science verification program. An 8 GHz wide Band 9 spectrum extracted over a 0.3 × 0.3 region near source B, containing more than 100 emission lines, illustrates the quality of the data.

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Section: Science Verification: Iras 16293-2422mentioning

confidence: 96%

Section: Science Verification: Iras 16293-2422mentioning

confidence: 99%

The ALMA Band 9 receiver

Baryshev

Hesper

Mena

et al. 2015

A&A

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“…Furthermore, using 1.3 mm ALMA dust continuum data with ∼0 1 resolution (R. Pokhrel et al 2017, in preparation), we show that SMM1-b is a binary with a separation of ∼0 3 (∼130 au), and that the high-velocity, one-sided SiO jet is driven by the eastern member of the binary. Highly asymmetric, one-sided outflows have been seen before (e.g., Pety et al 2006;Kristensen et al 2013;Loinard et al 2013;Codella et al 2014); the origin of the asymmetry is unknown, but it may offer important clues about outflow launching mechanisms or the distribution of ambient material near the driving source.…”

Section: Molecular Emissionmentioning

confidence: 99%

ALMA Observations of Dust Polarization and Molecular Line Emission from the Class 0 Protostellar Source Serpens SMM1

Hull

Girart

Tychoniec

et al. 2017

ApJ

113

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We present high angular resolution dust polarization and molecular line observations carried out with the Atacama Large Millimeter/submillimeter Array (ALMA) toward the Class 0 protostar Serpens SMM1. By complementing these observations with new polarization observations from the Submillimeter Array (SMA) and archival data from the Combined Array for Research in Millimeter-wave Astronomy (CARMA) and the James Clerk Maxwell Telescopes (JCMT), we can compare the magnetic field orientations at different spatial scales. We find major changes in the magnetic field orientation between large (∼0.1 pc) scales-where the magnetic field is oriented E-W, perpendicular to the major axis of the dusty filament where SMM1 is embedded-and the intermediate and small scales probed by CARMA (∼1000 au resolution), the SMA (∼350 au resolution), and ALMA (∼140 au resolution). The ALMA maps reveal that the redshifted lobe of the bipolar outflow is shaping the magnetic field in SMM1 on the southeast side of the source; however, on the northwestern side and elsewhere in the source, lowvelocity shocks may be causing the observed chaotic magnetic field pattern. High-spatial-resolution continuum and spectral-line observations also reveal a tight (∼130 au) protobinary system in SMM1-b, the eastern component of which is launching an extremely high-velocity, one-sided jet visible in both =  (J CO 2 1) and =  (J SiO 5 4); however, that jet does not appear to be shaping the magnetic field. These observations show that with the sensitivity and resolution of ALMA, we can now begin to understand the role that feedback (e.g., from protostellar outflows) plays in shaping the magnetic field in very young, star-forming sources like SMM1.

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“…Jet precession may occur in a variety of astrophysical objects, including low-mass star formation in the Galaxy (L1157 Gueth et al 1996;Kwon et al 2015;NGC 1333-IRAS4A Santangelo et al 2015L 1551IRS 5 Fridlund & Liseau 1994IRAS 16293-2422Kristensen et al 2013); Galactic micro-quasars (SS433 Blundell & Bowler 2005and 1E 1740.7-2942Luque-Escamilla et al 2015, and AGN radio jets (e.g. Veilleux et al 1993;Steffen 1997;Martí-Vidal et al 2011;Pyrzas et al 2015).…”

Section: Origin Of Precessionmentioning

confidence: 99%

A precessing molecular jet signaling an obscured, growing supermassive black hole in NGC 1377?

Aalto

Costagliola

Müller

et al. 2016

A&A

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With high resolution (0. 25 × 0. 18) ALMA CO 3−2 (345 GHz) observations of the nearby (D = 21 Mpc, 1 = 102 pc), extremely radio-quiet galaxy NGC 1377, we have discovered a high-velocity, very collimated nuclear outflow which we interpret as a molecular jet with a projected length of ±150 pc. The launch region is unresolved and lies inside a radius r < 10 pc. Along the jet axis we find strong velocity reversals where the projected velocity swings from −150 km s −1 to +150 km s −1 . A simple model of a molecular jet precessing around an axis close to the plane of the sky can reproduce the observations. The velocity of the outflowing gas is difficult to constrain due to the velocity reversals but we estimate it to be between 240 and 850 km s −1 and the jet to precess with a period P = 0.3−1.1 Myr. The CO emission is clumpy along the jet and the total molecular mass in the high-velocity (±(60 to 150 km s −1 )) gas lies between 2 × 10 6 M (light jet) and 2 × 10 7 M (massive jet). There is also CO emission extending along the minor axis of NGC 1377. It holds >40% of the flux in NGC 1377 and may be a slower, wide-angle molecular outflow which is partially entrained by the molecular jet. We discuss the driving mechanism of the molecular jet and suggest that it is either powered by a (faint) radio jet or by an accretion disk-wind similar to those found towards protostars. It seems unlikely that a massive jet could have been driven out by the current level of nuclear activity which should then have undergone rapid quenching. The light jet would only have expelled 10% of the inner gas and may facilitate nuclear activity instead of suppressing it. The nucleus of NGC 1377 harbours intense embedded activity and we detect emission from vibrationally excited HCN J = 4−3 ν 2 = 1 f which is consistent with hot gas and dust. We find large columns of H 2 in the centre of NGC 1377 which may be a sign of a high rate of recent gas infall. The dynamical age of the molecular jet is short (<1 Myr), which could imply that it is young and consistent with the notion that NGC 1377 is caught in a transient phase of its evolution. However, further studies are required to determine the age of the molecular jet, its mass and the role it is playing in the growth of the nucleus of NGC 1377.

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ALMA COJ= 6–5 observations of IRAS 16293–2422

Cited by 36 publications

References 19 publications

The ALMA Band 9 receiver

The ALMA Band 9 receiver

ALMA Observations of Dust Polarization and Molecular Line Emission from the Class 0 Protostellar Source Serpens SMM1

A precessing molecular jet signaling an obscured, growing supermassive black hole in NGC 1377?

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