We imaged the continuum and molecular line emission from Orion SourceI (SrcI) with up to 30 mas ... more We imaged the continuum and molecular line emission from Orion SourceI (SrcI) with up to 30 mas (12 au) resolution at 43, 99, 223, and 340 GHz in an attempt to probe the structure and chemistry of the circumstellar disk and bipolar outflow associated with this high-mass protostar. The continuum spectral index ranges from ∼2 along the midplane of the disk to ∼3 along the edges, consistent with dust that is optically thick in the midplane but becomes optically thin at the periphery. Salt (NaCl) emission is visible where the dust is optically thin; it provides a unique tracer of the velocity field within the disk. All other molecules that we have mapped-H 2 O, AlO, SiO, SiS, SO, and SO 2-appear to originate primarily in the bipolar outflow. The base of the outflow is corotating with the disk. SiS shows a filamentary structure that is most prominent along the edges of the outflow. The molecular distributions suggest that Si and Al released from dust grains in the disk react with oxygen derived from H 2 O to form SiO and AlO, and with SO and SO 2 to form SiS.
Astron. Astrophys. 257, 31-46 (1992) ASTRONOMY AND ASTROPHYSICS VLBI observations of active galac... more Astron. Astrophys. 257, 31-46 (1992) ASTRONOMY AND ASTROPHYSICS VLBI observations of active galactic nuclei at 3 mm LBBââth1, AEERogers2, M.Inoue3, S.Padin4, MCHWright5, A.Zensus6, AJKus7, DCBacker5, RSBooth1, JECarlstrom5, RLDickman8, DTEmerson9, ...
ABSTRACT Most theoretical models of bipolar outflows from young stars assume that the outflows fo... more ABSTRACT Most theoretical models of bipolar outflows from young stars assume that the outflows follow the magnetic-field direction. Yet, in the limited number of sources where dust polarization had already been mapped, misalignments of the outflow and magnetic field axes were common. We present results from the TADPOL survey, a key project at CARMA (the Combined Array for Research in Millimeter-wave Astronomy) that aims to roughly triple the number of high-resolution maps of dust polarization toward low-mass, Class 0 cores. The results accumulated thus far suggest that magnetic fields and bipolar outflows in low-mass cores are not tightly aligned, and may indeed be randomly oriented with respect to one another.
Aims. This work provides an update to existing reconstructions of the Galactic Faraday rotation s... more Aims. This work provides an update to existing reconstructions of the Galactic Faraday rotation sky by processing almost all Faraday rotation data sets available at the end of the year 2020. Observations of extra-Galactic sources in recent years have further illuminated the previously underconstrained southern celestial sky, as well as parts of the inner disc of the Milky Way, along with other regions. This has culminated in an all-sky data set of 55 190 data points, thereby comprising a significant expansion on the 41 330 used in previous works. At the same time, this novelty makes an updated separation of the Galactic component a promising enterprise. The increased source density allows us to present our results in a resolution of about 1.3 × 10−2 deg2 (46.8 arcmin2), which is a twofold increase compared to previous works. Methods. As for previous Faraday rotation sky reconstructions, this work is based on information field theory, namely, a Bayesian inference scheme for field-lik...
The Orion Nebula Cluster (ONC) is the nearest dense star-forming region at ∼400 pc away, making i... more The Orion Nebula Cluster (ONC) is the nearest dense star-forming region at ∼400 pc away, making it an ideal target to study the impact of high stellar density and proximity to massive stars (the Trapezium) on protoplanetary disk evolution. The OMC1 molecular cloud is a region of high extinction situated behind the Trapezium in which actively forming stars are shielded from the Trapezium’s strong radiation. In this work, we survey disks at high resolution with Atacama Large Millimeter/submillimeter Array at three wavelengths with resolutions of 0.″095 (3 mm; Band 3), 0.″048 (1.3 mm; Band 6), and 0.″030 (0.85 mm; Band 7) centered on radio Source I. We detect 127 sources, including 15 new sources that have not previously been detected at any wavelength. 72 sources are spatially resolved at 3 mm, with sizes from ∼8–100 au. We classify 76 infrared-detected sources as foreground ONC disks and the remainder as embedded OMC1 disks. The two samples have similar disk sizes, but the OMC1 sourc...
Planned instruments such as the Atacama Large Millimeter Array (ALMA), the Large Synoptic Survey ... more Planned instruments such as the Atacama Large Millimeter Array (ALMA), the Large Synoptic Survey Telescope (LSST) and the Square Kilometer Array (SKA) will measure their data in petabytes. Innovative approaches in signal processing, computing hardware, algorithms, ...
We imaged the continuum and molecular line emission from Orion SourceI (SrcI) with up to 30 mas ... more We imaged the continuum and molecular line emission from Orion SourceI (SrcI) with up to 30 mas (12 au) resolution at 43, 99, 223, and 340 GHz in an attempt to probe the structure and chemistry of the circumstellar disk and bipolar outflow associated with this high-mass protostar. The continuum spectral index ranges from ∼2 along the midplane of the disk to ∼3 along the edges, consistent with dust that is optically thick in the midplane but becomes optically thin at the periphery. Salt (NaCl) emission is visible where the dust is optically thin; it provides a unique tracer of the velocity field within the disk. All other molecules that we have mapped-H 2 O, AlO, SiO, SiS, SO, and SO 2-appear to originate primarily in the bipolar outflow. The base of the outflow is corotating with the disk. SiS shows a filamentary structure that is most prominent along the edges of the outflow. The molecular distributions suggest that Si and Al released from dust grains in the disk react with oxygen derived from H 2 O to form SiO and AlO, and with SO and SO 2 to form SiS.
Astron. Astrophys. 257, 31-46 (1992) ASTRONOMY AND ASTROPHYSICS VLBI observations of active galac... more Astron. Astrophys. 257, 31-46 (1992) ASTRONOMY AND ASTROPHYSICS VLBI observations of active galactic nuclei at 3 mm LBBââth1, AEERogers2, M.Inoue3, S.Padin4, MCHWright5, A.Zensus6, AJKus7, DCBacker5, RSBooth1, JECarlstrom5, RLDickman8, DTEmerson9, ...
ABSTRACT Most theoretical models of bipolar outflows from young stars assume that the outflows fo... more ABSTRACT Most theoretical models of bipolar outflows from young stars assume that the outflows follow the magnetic-field direction. Yet, in the limited number of sources where dust polarization had already been mapped, misalignments of the outflow and magnetic field axes were common. We present results from the TADPOL survey, a key project at CARMA (the Combined Array for Research in Millimeter-wave Astronomy) that aims to roughly triple the number of high-resolution maps of dust polarization toward low-mass, Class 0 cores. The results accumulated thus far suggest that magnetic fields and bipolar outflows in low-mass cores are not tightly aligned, and may indeed be randomly oriented with respect to one another.
Aims. This work provides an update to existing reconstructions of the Galactic Faraday rotation s... more Aims. This work provides an update to existing reconstructions of the Galactic Faraday rotation sky by processing almost all Faraday rotation data sets available at the end of the year 2020. Observations of extra-Galactic sources in recent years have further illuminated the previously underconstrained southern celestial sky, as well as parts of the inner disc of the Milky Way, along with other regions. This has culminated in an all-sky data set of 55 190 data points, thereby comprising a significant expansion on the 41 330 used in previous works. At the same time, this novelty makes an updated separation of the Galactic component a promising enterprise. The increased source density allows us to present our results in a resolution of about 1.3 × 10−2 deg2 (46.8 arcmin2), which is a twofold increase compared to previous works. Methods. As for previous Faraday rotation sky reconstructions, this work is based on information field theory, namely, a Bayesian inference scheme for field-lik...
The Orion Nebula Cluster (ONC) is the nearest dense star-forming region at ∼400 pc away, making i... more The Orion Nebula Cluster (ONC) is the nearest dense star-forming region at ∼400 pc away, making it an ideal target to study the impact of high stellar density and proximity to massive stars (the Trapezium) on protoplanetary disk evolution. The OMC1 molecular cloud is a region of high extinction situated behind the Trapezium in which actively forming stars are shielded from the Trapezium’s strong radiation. In this work, we survey disks at high resolution with Atacama Large Millimeter/submillimeter Array at three wavelengths with resolutions of 0.″095 (3 mm; Band 3), 0.″048 (1.3 mm; Band 6), and 0.″030 (0.85 mm; Band 7) centered on radio Source I. We detect 127 sources, including 15 new sources that have not previously been detected at any wavelength. 72 sources are spatially resolved at 3 mm, with sizes from ∼8–100 au. We classify 76 infrared-detected sources as foreground ONC disks and the remainder as embedded OMC1 disks. The two samples have similar disk sizes, but the OMC1 sourc...
Planned instruments such as the Atacama Large Millimeter Array (ALMA), the Large Synoptic Survey ... more Planned instruments such as the Atacama Large Millimeter Array (ALMA), the Large Synoptic Survey Telescope (LSST) and the Square Kilometer Array (SKA) will measure their data in petabytes. Innovative approaches in signal processing, computing hardware, algorithms, ...
Uploads
Papers by Melvyn Wright