A5042679343- Astrophysics and Star Formation Studies
- Molecular Spectroscopy and Structure
- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Atmospheric Ozone and Climate
- Phase Equilibria and Thermodynamics
- Astronomy and Astrophysical Research
- Solar and Space Plasma Dynamics
- Advanced Combustion Engine Technologies
- History and Developments in Astronomy
- Radio Astronomy Observations and Technology
- Astronomical Observations and Instrumentation
- Historical Astronomy and Related Studies
- Earth Systems and Cosmic Evolution
- Space Science and Extraterrestrial Life
- Geophysics and Gravity Measurements
- Atomic and Molecular Physics
- Space Satellite Systems and Control
- Astrophysical Phenomena and Observations
- Ionosphere and magnetosphere dynamics
- Mycorrhizal Fungi and Plant Interactions
- Gamma-ray bursts and supernovae
- Atmospheric and Environmental Gas Dynamics
- Thermodynamic properties of mixtures
- SAS software applications and methods
University of Copenhagen
2022-2024
University of Oklahoma
2019-2022
K Lab (United States)
1991
We present an overview of the Large Program, ``Early Planet Formation in Embedded Disks (eDisk)'', conducted with Atacama Millimeter/submillimeter Array (ALMA). The ubiquitous detections substructures, particularly rings and gaps, protoplanetary disks around T Tauri stars raise possibility that at least some planet formation may have already started during embedded stages star formation. In order to address exactly how when is initiated, program focuses on searching for substructures 12...
Abstract We have conducted a survey of 328 protostars in the Orion molecular clouds with Atacama Large Millimeter/submillimeter Array at 0.87 mm resolution ∼0.″1 (40 au), including observations Very 9 toward 148 ∼0.″08 (32 au). This is largest multiwavelength this by an order magnitude. use dust continuum emission and to measure disk radii masses Class 0, I, flat-spectrum protostars, characterizing evolution these properties protostellar phase. The mean for are <?CDATA...
Abstract While dust disks around optically visible, Class II protostars are found to be vertically thin, when and how settles the midplane unclear. As part of Atacama Large Millimeter/submillimeter Array large program, Early Planet Formation in Embedded Disks, we analyze edge-on, embedded, I protostar IRAS 04302+2247, also nicknamed “Butterfly Star.” With a resolution 0.″05 (8 au), 1.3 mm continuum shows an asymmetry along minor axis that is evidence thick geometrically disk viewed nearly...
Abstract We present observations of the Class 0 protostar IRAS 16544–1604 in CB 68 from “Early Planet Formation Embedded Disks (eDisk)” ALMA Large program. The target continuum and lines at 1.3 mm with an angular resolution ∼5 au. image reveals a dusty protostellar disk radius ∼30 au seen close to edge-on asymmetric structures along both major minor axes. While asymmetry axis can be interpreted as effect dust flaring, comes real nonaxisymmetric structure. C 18 O cubes clearly show gas that...
Abstract We performed radiative transfer calculations and observing simulations to reproduce the 1.3 mm dust-continuum C 18 O (2–1) images in Class I protostar R CrA IRS7B-a, observed with ALMA Large Program “Early Planet Formation Embedded Disks (eDisk).” found that a dust disk model passively heated by central cannot peak brightness temperature of continuum emission (∼195 K), regardless assumptions about opacity. Our calculation suggests viscous accretion heating is required high...
We characterize protostellar multiplicity in the Orion molecular clouds using ALMA 0.87~mm and VLA 9~mm continuum surveys toward 328 protostars. These observations are sensitive to projected spatial separations as small $\sim$20~au, we consider source up 10$^4$~au potential companions. The overall fraction (MF) companion (CF) for protostars 0.30$\pm$0.03 0.44$\pm$0.03, respectively, considering from 20 10$^4$~au. MFs CFs corrected contamination by unassociated young stars a probabilistic...
Studying the physical and chemical conditions of young embedded disks is crucial to constrain initial for planet formation. Here, we present Atacama Large Millimeter/submillimeter Array (ALMA) observations dust continuum at $\sim$0.06" (8 au) resolution molecular line emission $\sim$0.17" (24 toward Class 0 protostar L1527 IRS from Program eDisk (Early Planet Formation in Embedded Disks). The smooth without substructures, but asymmetric along both major minor axes disk as previously...
Constraining the physical and chemical structure of young embedded disks is crucial to understanding earliest stages planet formation. As part Early Planet Formation in Embedded Disks Atacama Large Millimeter/submillimeter Array Program, we present high spatial resolution ($\sim$0$.\!\!^{\prime\prime}$1 or $\sim$15 au) observations 1.3 mm continuum $^{13}$CO $J=$ 2-1, C$^{18}$O SO $J_N=$ $6_5$-$5_4$ molecular lines toward disk around Class I protostar L1489 IRS. The emission shows a...
Abstract We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of the Class I source Oph IRS 63 in context Early Planet Formation Embedded Disks large program. Our ALMA show a myriad protostellar features, such as shell-like bipolar outflow (in 12 CO), an extended rotating envelope structure 13 streamer connecting to disk C 18 O), and several small-scale spiral structures seen toward edge dust continuum SO). By analyzing velocity pattern CO O, we measure mass M ⋆ = 0.5...
Abstract Precise estimates of protostellar masses are crucial to characterize the formation stars low down brown dwarfs (BDs; M * < 0.08 ☉ ). The most accurate estimation mass uses Keplerian rotation in circumstellar disk around protostar. To apply method a protostar at low-mass end, we have observed Class 0 IRAS 16253-2429 using Atacama Large Millimeter/submillimeter Array (ALMA) 1.3 mm continuum an angular resolution 0.″07 (10 au), and 12 CO, C 18 O, 13 CO ( J = 2–1), SO N 6 5 −5 4 )...
Abstract Protostellar disks are an ubiquitous part of the star formation process and future sites planet formation. As Early Planet Formation in Embedded Disks large program, we present high angular resolution dust continuum (∼40 mas) molecular line (∼150 observations Class 0 protostar IRAS 15398–3359. The is small, compact, centrally peaked, while more extended structures found outflow directions. We perform a 2D Gaussian fitting find deconvolved size 2 σ radius disk to be 4.5 × 2.8 au 3.8...
Abstract We present high-resolution Karl G. Jansky Very Large Array (VLA) observations of the protostar L1527 IRS at 7 mm, 1.3 cm, and 2 cm wavelengths. detect edge-on dust disk all three wavelengths find that it is asymmetric, with southern side brighter than northern side. confirm this asymmetry through analytic modeling also flared mm. test data against models including gap features in intensity profile, though we cannot rule such out, they do not provide a statistically significant...
Abstract We have observed the Class 0/I protostellar system Ced110 IRS4 at an angular resolution of 0.″05 (∼10 au) as part Atacama Large Millimeter/submillimeter Array large program, Early Planet Formation in Embedded Disks. The 1.3 mm dust continuum emission reveals that is a binary with projected separation ∼250 au. emissions associated main source and its companion, named IRS4A IRS4B, respectively, exhibit disk-like shapes likely arise from disks around protostars. has radius ∼110 au...
We present high-resolution, high-sensitivity observations of the Class 0 protostar RCrA IRS5N as part Atacama Large Milimeter/submilimeter Array (ALMA) large program Early Planet Formation in Embedded Disks (eDisk). The 1.3 mm continuum emission reveals a flattened structure around IRS5N, consistent with protostellar disk early phases evolution. appears smooth and shows no substructures. However, brightness asymmetry is observed along minor axis disk, suggesting optically geometrically...
Abstract We present Atacama Large Millimeter/submillimeter Array (0.87 mm) and Very (9 observations toward OMC-2 FIR4 FIR3 within the Orion integral-shaped filament, thought to be two of nearest regions intermediate-mass star formation. characterize continuum sources these on ∼40 au (0.″1) scales associated molecular line emission at a factor ∼30 better resolution than previous similar wavelengths. identify six compact FIR4, four in FIR3, one additional source just outside FIR4. This is...
Abstract We present the first results from Early Planet Formation in Embedded Disks Atacama Large Millimeter/submillimeter Array Program toward Oph IRS43, a binary system of solar mass protostars. The 1.3 mm dust continuum observations resolve compact disk, ∼6 au radius, around northern component and show that disk southern is even smaller, ≲3 au. CO, 13 C 18 O maps reveal large cavity low-mass envelope shows kinematic signatures rotation infall extending out to ∼2000 An expanding CO bubble...
Abstract Young protostellar binary systems, with expected ages less than ∼10 5 yr, are little modified since birth, providing key clues to formation and evolution. We present a first look at the young, Class 0 system R CrA IRAS 32 from Early Planet Formation in Embedded Disks ALMA large program, which observed 1.3 mm continuum emission, 12 CO (2−1), 13 C 18 O SO (6 −5 4 ), nine other molecular lines that trace disks, envelopes, shocks, outflows. With resolution of ∼0.″03 (∼5 au, distance 150...
Context. Characterizing the dust thermal structure in protoplanetary disks is a fundamental task because surface temperature can affect both planetary formation and chemical evolution. Because depends on many parameters, including grain size, it be challenging to properly model structure. Many chemistry disk models usually employ sophisticated single designed reproduce effect of realistic population presumably composed large diversity sizes. This generally represents good approximation most...
We present observations toward HOPS 383, the first known outbursting Class 0 protostar located within Orion molecular cloud using ALMA, VLA, and SMA. The SMA reveal envelope scale continuum line emission surrounding 383 at 0.85 mm, 1.1 1.3 mm. images show that HCO$^+$ H$^{13}$CO$^+$ peaks on or near continuum, while N$_2$H$^+$ is reduced same position. This reflects underlying chemistry where CO evaporating close to destroys forming HCO$^+$. also observe outflow traced by $^{12}$CO ($J = 2...
We performed radiative transfer calculations and observing simulations to reproduce the 1.3-mm dust-continuum C$^{18}$O (2-1) images in Class I protostar R CrA IRS7B-a, observed with ALMA Large Program ``Early Planet Formation Embedded Disks (eDisk)". found that dust disk model passively heated by central cannot peak brightness temperature of continuum emission ($\sim$195 K), regardless assumptions about opacity. Our calculation suggests viscous accretion heating is required high...
Young protostellar binary systems, with expected ages less than $\sim$10$^5$ years, are little modified since birth, providing key clues to formation and evolution. We present a first look at the young, Class 0 system R CrA IRAS 32 from Early Planet Formation in Embedded Disks (eDisk) ALMA large program, which observed 1.3 mm continuum emission, $^{12}$CO (2-1), $^{13}$CO C$^{18}$O SO (6$_5$-5$_4$), nine other molecular lines that trace disk, envelope, shocks, outflows. With resolution of...
Abstract We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of the binary Class 0 protostellar system BHR 71 IRS1 and IRS2 as part Early Planet Formation in Embedded Disks (eDisk) ALMA Program. describe 12 CO ( J = 2–1), 13 C 18 O H 2 3 2,1 –2 2,0 ), SiO 5–4) molecular lines along with 1.3 mm continuum at high spatial resolution (∼0.″08 or ∼5 au). Dust emission is detected toward IRS2, a central compact component extended emission. The components are smooth show no...
The formation and evolution of disks early in the protostellar phase is an area study which ngVLA poised to make significant breakthroughs. high-sensitivity resolution at wavelengths 3~mm longer will enable forming be examined with unprecedented detail. need observe dust emission motivated by fact that these more likely optically thin, essential understanding structure disks. We explore feasibility detecting resolving a variety radii, masses, distances, out distances as large 1.5~kpc using...