A5076301056- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Molecular Spectroscopy and Structure
- Astro and Planetary Science
- Atmospheric Ozone and Climate
- Astronomy and Astrophysical Research
- Galaxies: Formation, Evolution, Phenomena
- Astronomical Observations and Instrumentation
- Astrophysical Phenomena and Observations
- Gamma-ray bursts and supernovae
- Spectroscopy and Laser Applications
- Advanced Combustion Engine Technologies
- Fluid Dynamics and Turbulent Flows
- Computational Fluid Dynamics and Aerodynamics
- Laser-Plasma Interactions and Diagnostics
- High-pressure geophysics and materials
- Advanced Chemical Physics Studies
- Astrophysics and Cosmic Phenomena
- Calibration and Measurement Techniques
- Atomic and Molecular Physics
- Cosmology and Gravitation Theories
- Space Science and Extraterrestrial Life
- Plasma and Flow Control in Aerodynamics
- High-Energy Particle Collisions Research
- Plant Parasitism and Resistance
Université Grenoble Alpes
2021-2024
Centre National de la Recherche Scientifique
2014-2024
Institut de Planétologie et d'Astrophysique de Grenoble
2022-2024
University of Chile
2015-2024
Universidad Bernardo O'Higgins
2017-2022
Astrophysique, Instrumentation et Modélisation
2014-2021
Université Paris Cité
2014-2021
CEA Paris-Saclay
2014-2021
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2014-2021
Délégation Paris 7
2014-2021
This review examines the state-of-the-art knowledge of high-mass star and massive cluster formation, gained from ambitious observational surveys, which acknowledge multi-scale characteristics these processes. After a brief overview theoretical models main open issues, we present searches for evolutionary phases first among high-luminosity sources more recently young protostars elusive prestellar cores. We then introduce most likely scenario emphasizes link formation to cloud formation....
We analyze a sample of 12 HST-selected edge-on protoplanetary disks for which the vertical extent emission layers can be constrained directly. present ALMA high angular resolution continuum images (0.1arcsec) these at two wavelengths, 0.89mm and 2.06mm (respectively bands 7 4), supplemented with archival band 6 data (1.33mm) where available. For most sources, millimeter is more compact than scattered light, both in radial directions. Six sources are resolved along their minor axis least one...
Abstract We present archival Atacama Large Millimeter/submillimeter Array band 6 observations of the 13 CO ( J = 2–1) and 12 molecular line emission protostellar system associated with HH 30. The shows accretion disk while outflow is traced by line. estimated a dynamical mass for central object 0.45 ± 0.14 M ⊙ , (1.83 0.19) × 10 −4 . presents an internal cavity as well multiple outflowing shell structures. distinguish three different shells constant expansion (∼4–6 km s −1 ) possible...
To constrain models of high-mass star formation, the Herschel/HOBYS KP aims at discovering massive dense cores (MDCs) able to host analogs low-mass prestellar cores, which have been searched for over past decade. We here focus on NGC6334, one best-studied HOBYS molecular cloud complexes. used Herschel PACS and SPIRE 70-500mu images NGC6334 complex complemented with (sub)millimeter mid-infrared data. built a complete procedure extract ~0.1 pc getsources software, simultaneously measures their...
Context: Star formation efficiency (SFE) theories are currently based on statistical distributions of turbulent cloud structures and a simple model star from cores. They remain poorly tested, especially at the highest densities. Aims: We investigate effects gas density SFE through measurements core (CFE). With total mass $\sim2\times10^4$ M$_\odot$, W43-MM1 ridge is one most convincing candidate precursor starburst clusters thus best place to formation. Methods: used high-angular resolution...
Tidal encounters in star clusters perturb discs around young protostars. In Cuello et al. (2019a, Paper I) we detailed the dynamical signatures of a stellar flyby both gas and dust. Flybys produce warped discs, spirals with evolving pitch angles, increasing accretion rates, disc truncation. Here present corresponding observational these features optical/near-infrared scattered light (sub-) millimeter continuum CO line emission. Using representative prograde retrograde for direct comparison,...
The ALMA-IMF Large Program imaged a total noncontiguous area of 53pc2, covering 15 extreme, nearby protoclusters the Milky Way. They were selected to span relevant early protocluster evolutionary stages. Our 1.3mm and 3mm observations provide continuum images that are homogeneously sensitive point-like cores with masses 0.2 0.6Msun, respectively, matched spatial resolution 2000au. We also detect lines probe structure, kinematics, chemistry, feedback over scales from clouds filaments cores....
The ALMA-IMF Large Program observed the W43-MM2-MM3 ridge, whose 1.3mm and 3mm ALMA 12m array continuum images reach a 2500au spatial resolution. We used both best-sensitivity line-free images, reduced noise with multi-resolution segmentation technique MnGSeg, derived most complete robust core catalog possible. Using two different extraction software packages, getsf GExt2D, we identified 200 compact sources, 100 common sources have on average fluxes consistent to within 30%. filtered...
ABSTRACT The formation of stellar clusters dictates the pace at which galaxies evolve, and solving question their will undoubtedly lead to a better understanding Universe as whole. While it is well known that star form within parsec-scale overdensities interstellar molecular gas called clumps, is, however, unclear whether these clumps represent high-density tip continuous gaseous flow gradually leads towards stars, or transition physical properties. Here, we present unique analysis sample 27...
Sites associated with high-mass star and cluster formation exhibit a so-called hot core phase, characterized by high temperatures column densities of complex organic molecules. We built comprehensive census candidates towards the ALMA-IMF protoclusters based on detection two CH3OCHO emission lines at 216.1 GHz. used source extraction algorithm GExt2D to identify peaks methyl formate (CH3OCHO) that is species commonly observed sites formation. up catalog 76 masses ranging from about 0.2 80...
We used PdBI observations of SiO (2-1) to investigate the morphology and profile emission within several massive dense clumps (MDCs) in Cygnus-X. find that most molecular outflows are detected both CO, although there some cases CO with no counterpart. a significant amount narrow line appears be unrelated outflows. The fraction total luminosity is not associated highly variable different MDCs (from 10% 90%); this might problem when extrapolating outflow properties from luminosities without...
Previous literature suggests that the densest structures in interstellar medium form through colliding flows, but patent evidence of this process is still missing. Recent proposes using SiO line emission to trace low-velocity shocks associated with cloud formation collision. In paper we investigate bright and extended SiO(2-1) observed along ~5 pc-long W43-MM1 ridge determine its origin. We used high angular resolution images HCN(1-0) lines obtained IRAM plateau de Bure (PdBI) interferometer...
Context. One of the central questions in astrophysics is origin initial mass function (IMF). It intrinsically linked to processes from which it originates, and hence its connection with core (CMF) must be elucidated. Aims. We aim measure CMF evolved W33-Main star-forming protocluster compare recently obtained other Galactic regions, including ones that are part ALMA-IMF program. Methods. used observations large programme: ~2′ × 2′ maps emission continuum selected lines at 1.3 mm 3 observed...
Numerical simulations have explored the possibility to form molecular clouds through either a quasi-static, self-gravitating mechanism or collision of gas streams lower-density clouds. They also quantitatively predict distribution matter at transition from atomic gases. We aim observationally test these models by studying environment W43, cloud complex near tip Galactic long bar. Using Galaxy-wide HI and 12CO surveys we searched for flowing toward W43 complex. estimated H2 mass surface...
Two major features of the prestellar CMF are: 1) a broad peak below 1 Msun, presumably corresponding to mean gravitational fragmentation scale, and 2) characteristic power-law slope, very similar Salpeter slope stellar initial mass function (IMF) at high-mass end. While recent Herschel observations have shown that is close thermal Jeans in marginally supercritical filaments, origin tail CMF/IMF end less clear. Inutsuka (2001) proposed theoretical scenario which can be understood as resulting...
The scaling relations and the star formation laws for molecular cloud complexes in Milky Way is investigated. We compare their masses $M_{\rm gas}$, mass surface densities $\Sigma_{M_{\rm gas}}$, radii $R$, velocity dispersions $\sigma$, rates $SFR$, SFR $\Sigma_{\rm SFR}$ with those of structures ranging from cores, clumps, Giant Molecular Clouds (GMCs), to Cloud Complexes (MCCs), Galaxies, spanning 8 orders magnitudes size 13 mass. MCC are mostly large ($R>50$ pc), massive ($\sim...
We aim to identify and characterize cores in the high-mass proto-cluster W49, determine their evolutionary stages measure associated lifetimes. built a catalog of 129 extracted from an ALMA 1.3 mm continuum image at 0.26" (2900 au) angular resolution. The association between Hyper/Ultra Compact HII (H/UC HII) regions was established analysis VLA 3.3 cm H30$\alpha$ line observations. also looked for emission hot molecular (HMCs) using methyl formate doublet 218.29 GHz. identified 40 with H/UC...
The mass segregation of stellar clusters could be primordial rather than dynamical. Despite the abundance studies for clusters, those progenitors are still scarce, so question on origin and evolution is open. Our goal to characterize structure NGC 2264 molecular cloud compare populations clumps young objects (YSOs) in this region whose rich YSO population has shown evidence sequential star formation. We separated Herschel column density map three subregions compared their power spectra using...
High-mass prestellar cores are extremely rare. The search for such objects has long been hindered by small sample sizes, leading to large uncertainties in their lifetimes and the conditions which high-mass stars ($> 8\,M_{\odot}$) form. We leverage ($\sim 580$ cores) detected ALMA-IMF survey identify both protostellar estimate relative lifetimes. use CO SiO outflows introduce a new automated method based on aperture line emission background subtraction systematically detect associated with...
ABSTRACT Here, we present the first results from ALMA observations of 1 mm polarized dust emission toward W43-MM1 high-mass star-forming clump. We have detected a highly fragmented filament with source masses ranging 14 M to 312 , where largest fragment, A, is believed be one most massive in our Galaxy. found smooth, ordered, and detailed polarization pattern throughout filament, which used derived magnetic field morphologies strengths for 12 out 15 fragments 0.2 9 mG. The dynamical...
The surroundings of HII regions can have a profound influence on their development, morphology, and evolution. This paper explores the effect environment H II in MonR2 molecular cloud. We aim to investigate density structure envelopes surrounding determine collapse ionisation expansion ages. Mon R2 cloud is an ideal target since it hosts region association. Column temperature images derived from Herschel data were used together model bubbles envelopes. resulting observational constraints...
High-mass analogues of low-mass prestellar cores are searched for to constrain the models high-mass star formation. Several cores, at various evolutionary stages, have been recently identified towards massive star-forming region W43-MM1 and amongst them a core candidate. We aim characterise chemistry in this candidate, referred as #6, its environment. Using ALMA high-spatial resolution data W43-MM1, we studied molecular content #6 neighbouring protostellar core, #3, which is similar size...