Publications (27)
HAWC+/SOFIA Multiwavelength Polarimetric Observations of OMC-1
David T. Chuss, B-G Andersson, John Bally +35
We report new polarimetric and photometric maps of the massive star-forming region OMC-1 using the HAWC+ instrument on the Stratospheric Observatory for Infrared Astronomy (SOFIA).…
Inclination-Induced Polarization of Scattered Millimeter Radiation from Protoplanetary Disks: The Case of HL Tau
Haifeng Yang, Zhi-Yun Li, Leslie Looney +1
Spatially resolved polarized millimeter/submillimeter emission has been observed in the disk of HL Tau and two other young stellar objects. It is usually interpreted as coming from…
Protoplanetary Disk Polarization at Multiple Wavelengths: Are Dust Populations Diverse?
Rachel E. Harrison, Zhe-Yu Daniel Lin, Leslie W. Looney +4
Millimeter and sub-millimeter observations of continuum linear dust polarization provide insight into dust grain growth in protoplanetary disks, which are the progenitors of planet…
ALMA Observations of Polarized 872 m Dust Emission from the Protostellar Systems VLA 1623 and L1527
Robert J. Harris, Erin G. Cox, Leslie W. Looney +8
We present high-sensitivity ( mJy, mJy), high-resolution (0.12-0.2 arcsec) observations of polarized 872 m dust emission from the young multi…
The VLA/ALMA Nascent Disk and Multiplicity (VANDAM) Survey of Orion Protostars. A Statistical Characterization of Class 0 and I Protostellar Disks
John J. Tobin, Patrick Sheehan, S. Thomas Megeath +33
We have conducted a survey of 328 protostars in the Orion molecular clouds with ALMA at 0.87 mm at a resolution of 0.1" (40 au), including observations with the VLA at 9 mm t…
Thermal Emission and Scattering by Aligned Grains: Plane-Parallel Model and Application to Multiwavelength Polarization of the HL Tau Disk
Zhe-Yu Daniel Lin, Zhi-Yun Li, Haifeng Yang +4
Telescopes are now able to resolve dust polarization across circumstellar disks at multiple wavelengths, allowing the study of the polarization spectrum. Most disks show clear evid…
The Life Cycle of Dust
Sarah Sadavoy, Mikako Matsuura, Lee Armus +24
Dust offers a unique probe of the interstellar medium (ISM) across multiple size, density, and temperature scales. Dust is detected in outflows of evolved stars, star-forming molec…
Validating Scattering-Induced (Sub)millimeter Disk Polarization through the Spectral Index, Wavelength-Dependent Polarization Pattern, and Polarization Spectrum: The Case of HD 163296
Zhe-Yu Daniel Lin, Zhi-Yun Li, Haifeng Yang +3
An increasing number of young circumstellar disks show strikingly ordered (sub)millimeter polarization orientations along the minor axis, which is strong evidence for polarization…
Highly Ordered and Pinched Magnetic Fields in the Class 0 Proto-Binary System L1448 IRS 2
Woojin Kwon, Ian Stephens, John Tobin +4
We have carried out polarimetric observations with the Atacama Large Millimeter/submillimeter Array (ALMA) toward the Class 0 protostellar system L1448 IRS 2, which is a proto-bina…
Astro2020 Science White Paper: The Formation and Evolution of Multiple Star Systems
John J. Tobin, Marina Kounkel, Stella Offner +13
Significant advances have been made over the past decade in the characterization of multiple protostar systems, enabled by the Karl G. Jansky Very Large Array (VLA), high-resolutio…
The Transition of Polarized Dust Thermal Emission from the Protostellar Envelope to the Disk Scale
Ka Ho Lam, Che-Yu Chen, Zhi-Yun Li +4
Polarized dust continuum emission has been observed with ALMA in an increasing number of deeply embedded protostellar systems. It generally shows a sharp transition going from the…
Detection of Irregular, Sub-mm Opaque Structures in the Orion Molecular Clouds: Protostars within 10000 years of formation?
Nicole Karnath, S. T. Megeath, John Tobin +10
We report ALMA and VLA continuum observations that potentially identify the four youngest protostars in the Orion Molecular Clouds taken as part of the Orion VANDAM program. These…
KFPA Examinations of Young STellar Object Natal Environments (KEYSTONE): Hierarchical Ammonia Structures in Galactic Giant Molecular Clouds
Jared Keown, James Di Francesco, Erik Rosolowsky +23
We present initial results from the K-band focal plane array Examinations of Young STellar Object Natal Environments (KEYSTONE) survey, a large project on the 100-m Green Bank Tele…
ALMA's Polarized View of 10 Protostars in the Perseus Molecular Cloud
Erin G. Cox, Robert J. Harris, Leslie W. Looney +4
We present 870 m ALMA dust polarization observations of 10 young Class 0/I protostars in the Perseus Molecular Cloud. At 0.35 (80 au) resolution, all of our sources s…
Applying the Velocity Gradient Technique in NGC 1333: Comparison with Dust Polarization Observations
Archana Soam, Ka Ho Yuen, Ian Stephens +3
Magnetic fields (B-fields) are ubiquitous in the interstellar medium (ISM), and they play an essential role in the formation of molecular clouds and subsequent star formation. Howe…
Time-Domain Photometry of Protostars at Far-Infrared and Submillimeter Wavelengths
William J. Fischer, Michael Dunham, Joel Green +16
The majority of the ultimate main-sequence mass of a star is assembled in the protostellar phase, where a forming star is embedded in an infalling envelope and encircled by a proto…
Polarization in Disks
Ian Stephens, Zhi-Yun Li, Haifeng Yang +24
Polarized dust emission outside of disks reveal the magnetic field morphology of molecular clouds. Within disks, however, polarized dust emission can arise from very different mech…
The VLA/ALMA Nascent Disk and Multiplicity (VANDAM) Survey of Orion Protostars I. Identifying and Characterizing the Protostellar Content of the OMC2-FIR4 and OMC2-FIR3 Regions
John J. Tobin, S. Thomas Megeath, Merel van 't Hoff +31
We present ALMA (0.87~mm) and VLA (9~mm) observations toward OMC2-FIR4 and OMC2-FIR3 within the Orion integral-shaped filament that are thought to be the nearest regions of interme…
Probing the Temperature Structure of Optically Thick Disks Using Polarized Emission of Aligned Grains
Zhe-Yu Daniel Lin, Zhi-Yun Li, Haifeng Yang +4
Polarized continuum emission from aligned grains in disks around young stellar objects can be used to probe the magnetic field, radiation anisotropy, or drift between dust and gas,…
Studying Magnetic Fields in Star Formation and the Turbulent Interstellar Medium
Laura Fissel, Charles L. H. Hull, Susan E. Clark +10
Understanding the physics of how stars form is a highly-prioritized goal of modern Astrophysics, in part because star formation is linked to both galactic dynamics on large scales…
Investigation of Hourglass-shaped Magnetic fields in the G35.20-0.74 Star-Forming Complex
O. R. Jadhav, L. K. Dewangan, A. K. Maity +7
To investigate the role of magnetic fields toward the G35N and G35S sub-regions in the G35.20-0.74 star-forming complex, we utilized multi-wavelength polarimetric observations from…
(Sub)millimeter Dust Polarization of Protoplanetary Disks from Scattering by Large Millimeter-Sized Irregular Grains
Zhe-Yu Daniel Lin, Zhi-Yun Li, Haifeng Yang +6
The size of dust grains, , is key to the physical and chemical processes in circumstellar disks, but observational constraints of grain size remain challenging. (Sub)millimeter…
Astro2020 Science White Paper: Measuring Protostar Masses: The Key to Protostellar Evolution
John J. Tobin, Stella Offner, Patrick Sheehan +10
Knowledge of protostellar evolution has been revolutionized with the advent of surveys at near-infrared to submillimeter wavelengths. This has enabled the bolometric luminosities a…
PICO: Probe of Inflation and Cosmic Origins
Shaul Hanany, Marcelo Alvarez, Emmanuel Artis +79
The Probe of Inflation and Cosmic Origins (PICO) is an imaging polarimeter that will scan the sky for 5 years in 21 frequency bands spread between 21 and 799 GHz. It will produce f…
HAWC+/SOFIA Polarimetry in L1688: Relative Orientation of Magnetic Field and Elongated Cloud Structure
Dennis Lee, Marc Berthoud, Che-Yu Chen +14
We present a study of the relative orientation between the magnetic field and elongated cloud structures for the Oph A and Oph E regions in L1688 in the Ophiuchus molecul…
The Radio Ammonia Mid-Plane Survey (RAMPS) Pilot Survey
Taylor Hogge, James Jackson, Ian Stephens +11
The Radio Ammonia Mid-Plane Survey (RAMPS) is a molecular line survey that aims to map a portion of the Galactic midplane in the first quadrant of the Galaxy (l = 10 deg - 40 deg,…
Variability in the Assembly of Protostellar Systems
Joel D. Green, Yao-Lun Yang, Tom Megeath +17
Understanding the collapse of clouds and the formation of protoplanetary disks is essential to understanding the formation of stars and planets. Infall and accretion, the mass-aggr…