We present the first detection and mapping of the HD 32297 debris disk at 1.3 mm with the Combine... more We present the first detection and mapping of the HD 32297 debris disk at 1.3 mm with the Combined ARray for Millimeter Astronomy (CARMA). With a sub-arcsecond beam, this detection represents the highest angular resolution (sub)mm debris disk observation made to date. Our model fits to the spectral energy distribution from the CARMA flux and new Spitzer MIPS photometry support the earlier suggestion that at least two, possibly three, distinct grain populations are traced by the current data. The observed millimeter map shows an asymmetry between the northeast and southwest disk lobes, suggesting large grains may be trapped in resonance with an unseen exoplanet. Alternatively, the observed morphology could result from the recent breakup of a massive planetesimal. A similar-scale asymmetry is also observed in scattered light but not in the mid-infrared. This contrast between asymmetry at short and long wavelengths and symmetry at intermediate wavelengths is in qualitative agreement wi...
We present a new method to use polarimetric measurements to estimate the relative orientations of... more We present a new method to use polarimetric measurements to estimate the relative orientations of the star+disk system in each component of Pre Main Sequence (PMS) T Tauri binary stars. The principles of the method are presented, together with a review of polarimetric data available in the literature on wide systems (8-40arcsec ) in Taurus. We show that this method
We propose to use NIRI to measure the depth and shape of the 3(micron) water ice absorption featu... more We propose to use NIRI to measure the depth and shape of the 3(micron) water ice absorption feature in three edge-on disks in the Ophiuchus molecular cloud. This will provide us with an estimate of the total column density of ice in these disks and an indication of the thermal processing it has experienced. In protoplanetary disks, water ice coats
We will present an overview of the main features of the current and next (to be released at the e... more We will present an overview of the main features of the current and next (to be released at the end of the summer) versions of the ASPRO software that are being developed by the JMMC to prepare VLTI observing programs. To help ASPRO users prepare their AMBER and MIDI proposals, an active helpdesk will also be available.
Proceedings of the International Astronomical Union, 2013
Using photometry at just two wavelengths it is possible to fit a blackbody to the spectrum of inf... more Using photometry at just two wavelengths it is possible to fit a blackbody to the spectrum of infrared excess that is the signature of a debris disc. From this the location of the dust can be inferred. However, it is well known that dust in debris discs is not a perfect blackbody. By resolving debris discs we can find the actual location of the dust and compare this to that inferred from the blackbody fit. Using the Herschel Space Observatory we resolved many systems as part of the DEBRIS survey. Here we discuss a sample of 9 discs surrounding A stars and find that the discs are actually located between 1 and 2.5 times further from their star than predicted by blackbody fits to the spectral energy distribution (SED). The variation in this ratio is due to differences in stellar luminosities, location of the dust, size distribution and composition of the dust.
Proceedings of the International Astronomical Union, 2013
We present new high-resolution observations and modeling of SSTtau J042021+ 281349, a 400 AU-radi... more We present new high-resolution observations and modeling of SSTtau J042021+ 281349, a 400 AU-radius edge-on protoplanetary disk. We have gathered visible and near-infrared scattered light images of the system with the Hubble Space Telescope and Keck adaptive optics system, as well as a 1.3 mm continuum map with CARMA. Compared to the well-known HH 30 disk, this new system is remarkable because of its spectacular bipolar jet and the high degree of lateral symmetry of the disk. Indeed, we argue that this system is a “cleaner” prototype for edge-on disks. In addition, the apparent achromaticity of dust properties (most notably the almost grey opacity law) from the visible to the near-infrared in this disk suggests that it is in an advanced stage of dust evolution.
We present the first detection and mapping of the HD 32297 debris disk at 1.3 mm with the Combine... more We present the first detection and mapping of the HD 32297 debris disk at 1.3 mm with the Combined ARray for Millimeter Astronomy (CARMA). With a sub-arcsecond beam, this detection represents the highest angular resolution (sub)mm debris disk observation made to date. Our model fits to the spectral energy distribution from the CARMA flux and new Spitzer MIPS photometry support the earlier suggestion that at least two, possibly three, distinct grain populations are traced by the current data. The observed millimeter map shows an asymmetry between the northeast and southwest disk lobes, suggesting large grains may be trapped in resonance with an unseen exoplanet. Alternatively, the observed morphology could result from the recent breakup of a massive planetesimal. A similar-scale asymmetry is also observed in scattered light but not in the mid-infrared. This contrast between asymmetry at short and long wavelengths and symmetry at intermediate wavelengths is in qualitative agreement wi...
We present a new method to use polarimetric measurements to estimate the relative orientations of... more We present a new method to use polarimetric measurements to estimate the relative orientations of the star+disk system in each component of Pre Main Sequence (PMS) T Tauri binary stars. The principles of the method are presented, together with a review of polarimetric data available in the literature on wide systems (8-40arcsec ) in Taurus. We show that this method
We propose to use NIRI to measure the depth and shape of the 3(micron) water ice absorption featu... more We propose to use NIRI to measure the depth and shape of the 3(micron) water ice absorption feature in three edge-on disks in the Ophiuchus molecular cloud. This will provide us with an estimate of the total column density of ice in these disks and an indication of the thermal processing it has experienced. In protoplanetary disks, water ice coats
We will present an overview of the main features of the current and next (to be released at the e... more We will present an overview of the main features of the current and next (to be released at the end of the summer) versions of the ASPRO software that are being developed by the JMMC to prepare VLTI observing programs. To help ASPRO users prepare their AMBER and MIDI proposals, an active helpdesk will also be available.
Proceedings of the International Astronomical Union, 2013
Using photometry at just two wavelengths it is possible to fit a blackbody to the spectrum of inf... more Using photometry at just two wavelengths it is possible to fit a blackbody to the spectrum of infrared excess that is the signature of a debris disc. From this the location of the dust can be inferred. However, it is well known that dust in debris discs is not a perfect blackbody. By resolving debris discs we can find the actual location of the dust and compare this to that inferred from the blackbody fit. Using the Herschel Space Observatory we resolved many systems as part of the DEBRIS survey. Here we discuss a sample of 9 discs surrounding A stars and find that the discs are actually located between 1 and 2.5 times further from their star than predicted by blackbody fits to the spectral energy distribution (SED). The variation in this ratio is due to differences in stellar luminosities, location of the dust, size distribution and composition of the dust.
Proceedings of the International Astronomical Union, 2013
We present new high-resolution observations and modeling of SSTtau J042021+ 281349, a 400 AU-radi... more We present new high-resolution observations and modeling of SSTtau J042021+ 281349, a 400 AU-radius edge-on protoplanetary disk. We have gathered visible and near-infrared scattered light images of the system with the Hubble Space Telescope and Keck adaptive optics system, as well as a 1.3 mm continuum map with CARMA. Compared to the well-known HH 30 disk, this new system is remarkable because of its spectacular bipolar jet and the high degree of lateral symmetry of the disk. Indeed, we argue that this system is a “cleaner” prototype for edge-on disks. In addition, the apparent achromaticity of dust properties (most notably the almost grey opacity law) from the visible to the near-infrared in this disk suggests that it is in an advanced stage of dust evolution.
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Papers by G. Duchene