A5018695775- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Molecular Spectroscopy and Structure
- Astronomy and Astrophysical Research
- Galaxies: Formation, Evolution, Phenomena
- Atmospheric Ozone and Climate
- Gamma-ray bursts and supernovae
- Astrophysics and Cosmic Phenomena
- Astronomical Observations and Instrumentation
- Superconducting and THz Device Technology
- Astrophysical Phenomena and Observations
- Adaptive optics and wavefront sensing
- Planetary Science and Exploration
- Radio Astronomy Observations and Technology
- Pulsars and Gravitational Waves Research
- Solar and Space Plasma Dynamics
- Isotope Analysis in Ecology
- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Advanced Chemical Physics Studies
- Calibration and Measurement Techniques
- Ionosphere and magnetosphere dynamics
- Space Exploration and Technology
- Library Science and Administration
Laboratoire de Physique des 2 Infinis Irène Joliot-Curie
2024-2025
CEA Paris-Saclay
2015-2024
Université Paris-Saclay
2016-2024
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2015-2024
Université Paris Cité
2015-2024
Centre National de la Recherche Scientifique
2015-2024
Center for Astrophysics Harvard & Smithsonian
2014-2024
Astrophysique, Instrumentation et Modélisation
2015-2024
Délégation Paris 7
2015-2024
Sorbonne Paris Cité
2018-2024
We summarize the first results from Gould Belt survey, obtained toward Aquila Rift and Polaris Flare regions during 'science demonstration phase' of Herschel. Our 70-500 micron images taken in parallel mode with SPIRE PACS cameras reveal a wealth filamentary structure, as well numerous dense cores embedded filaments. Between ~ 350 500 prestellar 45-60 Class 0 protostars can be identified field, while unbound starless no are observed field. The core mass function (CMF) derived for region...
Aims. The EROS-2 project was designed to test the hypothesis that massive compact halo objects (the so-called "machos") could be a major component of dark matter Milky Way galaxy. To this end, monitored over 6.7 years stars in Magellanic clouds for microlensing events caused by such objects.
We present the first measurement of planet frequency beyond "snow line," for planet-to-star mass-ratio interval −4.5 < log q −2, corresponding to range ice giants gas giants. find at mean mass ratio = 5 × 10−4 with no discernible deviation from a flat (Öpik's law) distribution in log-projected separation s. The determination is based on sample six planets detected intensive follow-up observations high-magnification (A>200) microlensing events during 2005–2008. sampled host stars have typical...
The origin and possible universality of the stellar initial mass function (IMF) is a major issue in astrophysics. One main objectives Herschel Gould Belt Survey to clarify link between prestellar core (CMF) IMF. We present discuss derived from data for large population cores discovered with SPIRE PACS Aquila Rift cloud complex at d ~ 260 pc. detect total 541 starless entire ~11 deg^2 area field imaged 70-500 micron SPIRE/PACS. Most these appear be gravitationally bound, thus nature. Our...
We present a 69 arcmin$^2$ ALMA survey at 1.1mm, GOODS-ALMA, matching the deepest HST-WFC3 H-band part of GOODS-South field. taper 0"24 original image with homogeneous and circular synthesized beam 0"60 to reduce number independent beams - thus reducing purely statistical spurious detections optimize sensitivity point sources. extract catalogue galaxies selected by identify sources without HST counterparts down 5$\sigma$ limiting depth H=28.2 AB (HST/WFC3 F160W). detects 20 brighter than 0.7...
Abstract Iron inclusions embedded inside dust grains play a crucial role in both internal alignment (IA) via Barnett relaxation and external the MAgnetically Enhanced RAdiative Torque (MRAT) mechanism. Moreover, inelastic is predicted to dominate over driving IA of micron-sized very large (VLGs) above 10 μ m. Yet, detailed modeling polarized thermal emission from Class 0/I young stellar objects (YSOs) taking into account these effects their observational constraints still lacking. In this...
We report the detection of cool, Jovian-mass planet MOA-2007-BLG-400Lb. The was detected in a high-magnification microlensing event (with peak magnification A_max = 628) which primary lens transited source, resulting dramatic smoothing event. angular extent region perturbation due to is significantly smaller than size and as result planetary signature also smoothed out by finite source size. Thus deviation from single-lens fit broad relatively weak (~ few percent). Nevertheless, we...
Aims. We report the discovery of a planet with high planet-to-star mass ratio in microlensing event MOA-2009-BLG-387, which exhibited pronounced deviations over 12-day interval, one longest for any planetary event. The host is an M dwarf, range 0.07 M⊙ < Mhost 0.49 at 90% confidence. planet-star q = 0.0132 ± 0.003 has been measured extremely well, so best-estimated mass, mp 2.6 Jupiter masses median 0.19 M⊙.
Millimeter-wave continuum astronomy is today an indispensable tool for both general Astrophysics studies and Cosmology. General purpose, large field-of-view instruments are needed to map the sky at intermediate angular scales not accessible by high-resolution interferometers coarse resolution space-borne or ground-based surveys. These have be installed focal plane of largest single-dish telescopes. In this context, we constructed deployed a multi-thousands pixels dual-band (150 260 GHz,...
We present the first example of binary microlensing for which parameter measurements can be verified (or contradicted) by future Doppler observations. This test is made possible a confluence two relatively unusual circumstances. First, lens bright enough (I=15.6) to permit measurements. Second, we measure not only usual 7 binary-lens parameters, but also 'microlens parallax' (which yields mass) and components instantaneous orbital velocity. Thus measure, effectively, 6 'Kepler+1' parameters...
The formation process of binary stars and multiple systems is poorly understood. Here, we seek to determine the typical outcome protostellar collapse constrain models by core fragmentation during collapse, using high-resolution millimeter continuum imaging very young (Class 0) protostars observed at beginning main accretion phase. We carried out a pilot study 5 Class 0 objects, most extended (A) configuration IRAM PdBI 1.3 mm, which allow us probe multiplicity down separations ~50 AU...
Abridged -- We present an analysis of the Aquila Rift complex which addresses questions star formation rate (SFR), efficiency (SFE) and typical lifetime Class 0 protostellar phase in two nearby cluster-forming clumps: Serpens South W40 protoclusters. carried out a 1.2 mm dust continuum mapping with MAMBO bolometer array on IRAM 30m telescope. perform systematic source extraction our millimeter map. Based complementary data from Herschel Gould Belt survey Spitzer maps, we characterize SEDs 77...
The role of the magnetic field during protostellar collapse is poorly constrained from an observational point view, although it could be significant if we believe state-of-the-art models formation. We present polarimetric observations 233 GHz thermal dust continuum emission obtained with ALMA in B335 Class 0 protostar. Linearly polarized arising circumstellar material envelope detected at all scales probed by our observations, radii 50 to 1000 au. structure producing polarization has a very...
Five years of eros data towards the Small Magellanic Cloud have been searched for gravitational microlensing events, using a new, more accurate method to assess impact stellar blending on efficiency. Four long-duration candidates found which, if they are hint at non-halo population lenses. Combined with results from other observation programs, this analysis yields strong limits amount Galactic dark matter made compact objects. Less than 25% standard halo can be composed objects mass between...
As part of the science demonstration phase <i>Herschel<i/> mission Gould Belt key program, Aquila rift molecular complex has been observed. The complete ~ 3.3° × imaging with SPIRE 250/350/500 <i>μ<i/>m and PACS 70/160 allows a deep investigation embedded protostellar phases, probing dust emission from warm inner regions at 70 160 to bulk cold envelopes between 250 500 <i>μ<i/>m. We used systematic detection technique operating simultaneously on all bands build sample protostars. Spectral...
Aims: We focus on the kinematical properties of a proto-binary to study infall and rotation gas towards its two protostellar components. Methods: present ALMA Science Verification observations with high-spectral resolution IRAS 16293-2422 at 220.2 GHz. The wealth molecular lines in this source very high spectral offered by allow us kinematics unprecedented detail. Results: first detection an inverse P-Cygni profile B three brightest lines. line profiles are fitted simple two-layer model...
The filament IRDC G035.39--00.33 in the W48 molecular complex is one of darkest infrared clouds observed by \textit{Spitzer}. It has been PACS (70 and 160\,$\micron$) SPIRE (250, 350, 500\,$\micron$) cameras \textit{Herschel} Space Observatory as part cloud framework HOBYS key programme. observations reveal a sample 28 compact sources (deconvolved FWHM sizes $<$0.3 pc) complete down to $\sim$$5 \msun$ its surroundings. Among them, 13 are massive dense cores with masses $>$$20 \msun$....
We present results derived from the first multi-chord stellar occultations by transneptunian object (50000) Quaoar, observed on 2011 May 4 and 2012 February 17, a single-chord occultation October 15. If timing of five chords obtained in were correct, then Quaoar would possess topographic features (crater or mountain) that be too large for body this mass. An alternative model consists applying time shifts to some account possible errors. Satisfactory elliptical fits are possible, yielding an...
Galactic black hole binaries produce powerful outflows with emit over almost the entire electromagnetic spectrum. Here, we report first detection Herschel observatory of a variable far-infrared source associated compact jets transient GX 339-4 during decay its recent 2010-2011 outburst, after transition to hard state. We also outline results very sensitive radio observations conducted Australia Telescope Compact Array, along series near-infrared, optical (OIR) and X-ray observations,...
We use PACS and SPIRE continuum data at 160 μm, 250 350 500 μm from the Herschel Gould Belt Survey to sample seven clumps in Perseus: B1, B1-E, B5, IC 348, L1448, L1455, NGC 1333. Additionally, we identify characterize embedded Class 0 protostars using detections of compact sources 70 as well archival Spitzer catalogs SCUBA 850 photometric data. 28 candidate protostars, four which are newly discovered not identified with Spitzer. find that star formation efficiency clumps, traced by...