363 citations · 7.5k across the 142 of their papers we have counts for
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The Asymmetric Bipolar Fe II Jet and H2 Outflow of TMC1A Resolved with JWST's NIRSpec IFU
Korash Assani, Daniel Harsono, Jon Ramsey +10
(abridged) Protostellar outflows exhibit large variations in their structure depending on the observed gas emission. This study analyzes the atomic jet and molecular outflow in the…
Linking ice and gas in the Coronet cluster in Corona Australis
G. Perotti, J. K. Jørgensen, W. R. M. Rocha +7
During the journey from the cloud to the disc, the chemical composition of the protostellar envelope material can be either preserved or processed to varying degrees depending on t…
JWST Peers into the Class I Protostar TMC1A: Atomic Jet and Spatially Resolved Dissociative Shock Region
Daniel Harsono, Per Bjerkeli, Jon Ramsey +6
Outflows and winds launched from young stars play a crucial role in the evolution of protostars and the early stages of planet formation. However, the specific details of the mecha…
Physical properties of accretion shocks toward the Class I protostellar system Oph-IRS 44
E. Artur de la Villarmois, V. V. Guzmán, J. K. Jørgensen +6
(Abridged) Physical processes such as accretion shocks are thought to be common in the protostellar phase, where the envelope component is still present, and they can release molec…
Protostellar Interferometric Line Survey of the Cygnus X region (PILS-Cygnus) -- First results: observations of CygX-N30
S. J. van der Walt, L. E. Kristensen, J. K. Jørgensen +5
(Abridged) Complex organic molecules (COMs) are commonly detected in and near star-forming regions. However, the dominant process in the release of these COMs from the icy grains -…
Steady Wind-Blown Cavities within Infalling Rotating Envelopes: Application to the Broad Velocity Component in Young Protostars
Lichen Liang, Doug Johnstone, Sylvie Cabrit +1
Wind-driven outflows are observed around a broad range of accreting objects throughout the Universe, ranging from forming low-mass stars to super-massive black holes. We study the…
Feedback of molecular outflows from protostars in NGC 1333, revealed by Herschel and Spitzer spectro-imaging observations
Odysseas Dionatos, Lars. E. Kristensen, Mario Tafalla +2
Large scale spectral maps of star forming regions enable the comparative study of the gas excitation around an ensemble of sources at a common frame of reference, providing direct…
Missing water in Class I protostellar disks
Daniel Harsono, Magnus Persson, Alyssa Ramos +10
Water is a key volatile that provides insights into the initial stages of planet formation. The low water abundances inferred from water observations toward low-mass protostellar o…
Chemical and kinematic structure of extremely high-velocity molecular jets in the Serpens Main star-forming region
Łukasz Tychoniec, Charles L. H. Hull, Lars E. Kristensen +3
The fastest molecular component to the protostellar outflows -- extremely high-velocity (EHV) molecular jets -- are still puzzling since they are seen only rarely. The first aim is…
ALMA observations of water deuteration: A physical diagnostic of the formation of protostars
S. S. Jensen, J. K. Jørgensen, L. E. Kristensen +5
The deuterium fractionation of water can serve as a tracer for the chemical and physical evolution of water during star formation and can constrain the origin of water in Solar Sys…
Kinematics around the B335 protostar down to au scales
Per Bjerkeli, Jon P. Ramsey, Daniel Harsono +6
Context. The relationship between outflow launching and formation of accretion disks around young stellar objects is still not entirely understood, which is why spectrally and spat…
The Bridge: a transient phenomenon of forming stellar multiples
Michael Kuffmeier, Hannah Calcutt, Lars E. Kristensen
Observations with modern instruments such as Herschel reveal that stars form clustered inside filamentary arms of ~1 pc length embedded in Giant Molecular Clouds. On smaller scales…
Revealing the chemical structure of the Class I disc Oph-IRS 67
E. Artur de la Villarmois, L. E. Kristensen, J. K. Jørgensen
(Abridged) The purpose of this paper is to explore the structure of a line-rich Class I protobinary source, Oph-IRS 67, and analyse the differences and similarities with Class 0 an…
Physical and chemical fingerprint of protostellar disc formation
E. Artur de la Villarmois, J. K. Jørgensen, L. E. Kristensen +5
(Abridged) The purpose of this paper is to explore and compare the physical and chemical structure of Class I low-mass protostellar sources on protoplanetary disc scales. We presen…
The ALMA-PILS survey: The first detection of doubly-deuterated methyl formate (CHD2OCHO) in the ISM
S. Manigand, H. Calcutt, J. K. Jørgensen +9
Studies of deuterated isotopologues of complex organic molecules can provide important constraints on their origin in regions of star formation. In particular, the abundances of de…
The ALMA-PILS survey: Stringent limits on small amines and nitrogen-oxides towards IRAS 16293-2422B
N. F. W. Ligterink, H. Calcutt, A. Coutens +8
Hydroxylamine (NHOH) and methylamine (CHNH) have both been suggested as precursors to the formation of amino acids and are therefore of interest to prebiotic chem…
Protostellar half-life: new methodology and estimates
L. E. Kristensen, M. M. Dunham
(Abridged) Protostellar systems evolve from prestellar cores, through the deeply embedded stage and then disk-dominated stage, before they end up on the main sequence. Knowing how…
Evidence for the start of planet formation in a young circumstellar disk
Daniel Harsono, Per Bjerkeli, Matthijs H. D. van der Wiel +4
The growth of dust grains in protoplanetary disks is a necessary first step towards planet formation. This growth has been inferred via observations of thermal dust emission toward…
Chemistry of a newly detected circumbinary disk in Ophiuchus
E. Artur de la Villarmois, L. E. Kristensen, J. K. Jørgensen +6
(Abridged) Astronomers recently started discovering exoplanets around binary systems. Therefore, understanding the formation and evolution of circumbinary disks is crucial for a co…
The Herschel-PACS legacy of low-mass protostars: Properties of warm and hot gas and its origin in far-UV illuminated shocks
Agata Karska, Michael J. Kaufman, Lars E. Kristensen +11
Recent observations from Herschel allow the identification of important mechanisms responsible for the heating of gas surrounding low-mass protostars and its subsequent cooling in…
The ALMA-PILS survey: 3D modeling of the envelope, disks and dust filament of IRAS 16293-2422
S. K. Jacobsen, J. K. Jørgensen, M. H. D. van der Wiel +8
Context. The Class 0 protostellar binary IRAS 16293-2422 is an interesting target for (sub)millimeter observations due to, both, the rich chemistry toward the two main components o…
Oxygen budget in low-mass protostars: the NGC1333-IRAS4A R1 shock observed in [OI] at 63 um with SOFIA-GREAT
L. E. Kristensen, A. Gusdorf, J. C. Mottram +5
In molecular outflows from forming low-mass protostars, most oxygen is expected to be locked up in water. However, Herschel observations have shown that typically an order of magni…
Protostellar accretion traced with chemistry. High resolution C18O and continuum observations towards deeply embedded protostars in Perseus
Søren Frimann, Jes K. Jørgensen, Michael M. Dunham +6
Context: Understanding how accretion proceeds is a key question of star formation, with important implications for both the physical and chemical evolution of young stellar objects…
Outflows, infall and evolution of a sample of embedded low-mass protostars. The William Herschel Line Legacy (WILL) survey
J. C. Mottram, E. F. van Dishoeck, L. E. Kristensen +22
[Abridged] We present spectroscopic observations in HO, CO and related species with \textit{Herschel} HIFI and PACS, as well as ground-based follow-up with the JCMT and APEX…