Patrice Bouchet - Academia.edu (original) (raw)
Papers by Patrice Bouchet
Quasi-simultaneous multifrequency observations from radio to X-rays of the bright quasar 3C273 fo... more Quasi-simultaneous multifrequency observations from radio to X-rays of the bright quasar 3C273 for several epochs between December 1983 and March 1986 are presented. The light curves in the different wavebands and the overall spectral energy distribution are analyzed. The NIR and optical fluxes showed small variations during the period considered, whereas the hard X-ray flux decreased by a factor of about 2 at the beginning of 1984, remained low during 1984-1985, and increased again by about 40 percent at the beginning of 1986. The soft X-ray flux varied several times by 20-40 percent, with no apparent underlying trend. In the submillimeter region, the flux remained constant during 1984, decreased in 1985, and again in 1986 to reach its lowest known level. The variations occurred at different epochs in the different wavebands, requiring the presence of different, although possibly related, emission components dominating the flux in the different spectral regions.
The Astrophysical Journal, 2020
Spitzerʼs final Infrared Array Camera observations of SN 1987A show the 3.6 and 4.5 μm emission f... more Spitzerʼs final Infrared Array Camera observations of SN 1987A show the 3.6 and 4.5 μm emission from the equatorial ring (ER) continues a period of steady decline. Deconvolution of the images reveals that the emission is dominated by the ring, not the ejecta, and is brightest on the west side. Decomposition of the marginally resolved emission also confirms this, and shows that the west side of the ER has been brightening relative to the other portions of the ER. The infrared morphological changes resemble those seen in both the soft X-ray emission and the optical emission. The integrated ER light curves at 3.6 and 4.5 μm are more similar to the optical light curves than the soft X-ray light curve, though differences would be expected if dust is responsible for this emission and its destruction is rapid. Future observations with the James Webb Space Telescope will continue to monitor the ER evolution, and will reveal the true spectrum and nature of the material responsible for the broadband emission at 3.6 and 4.5 μm. The present observations also serendipitously reveal a nearby variable source, subsequently identified as a Be star, that has gone through a multiyear outburst during the course of these observations.
Astronomy & Astrophysics, 1999
We present ISO observations made between 2.5 and 180 mu m of the nearby G0V dwarf HD 207129 taken... more We present ISO observations made between 2.5 and 180 mu m of the nearby G0V dwarf HD 207129 taken as part of a large survey of nearby main-sequence stars in search of debris discs. HD 207129 emits radiation in excess of the photospheric flux density between at least 60 and 180 mu m. The infrared excess is explained by a
The Astrophysical Journal, 2012
We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2... more We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M, and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on the Hubble Space Telescope. This dataset provides unique spectral time series down to 2000 Å. Significant diversity is seen in the near-maximum-light spectra (∼ 2000-3500 Å) for this small sample. The corresponding photometric data, together with archival data from Swift Ultraviolet/Optical Telescope observations, provide further evidence of increased dispersion in the UV emission with respect to the optical. The peak luminosities measured in the uvw1/F250W filter are found to correlate with the B-band light-curve shape parameter ∆m 15 (B), but with much larger scatter relative to the correlation in the broad-band B band (e.g., ∼ 0.4 mag versus ∼ 0.2 mag for those with 0.8 < ∆m 15 (B) < 1.7 mag). SN 2004dt is found as an outlier of this correlation (at > 3σ), being brighter than normal SNe Ia such as SN 2005cf by ∼ 0.9 mag and ∼ 2.0 mag in the uvw1/F250W and uvm2/F220W filters, respectively. We show that different progenitor metallicity or line-expansion velocities alone cannot explain such a large discrepancy. Viewing-angle effects, such as due to an asymmetric explosion, may have a significant influence on the flux emitted in the UV region. Detailed modeling is needed to disentangle and quantify the above effects.
The results on Vega-like stars obtained with ISO are discussed. We find that the incidence of Veg... more The results on Vega-like stars obtained with ISO are discussed. We find that the incidence of Vega-like disks is approximately 21% on average, with some dependency upon the spectral type. While young stars do more frequently show disks than old stars, there is no clear trend in the amount of dust seen at different ages. We also discuss the discovery
The Astrophysical Journal, 2014
Supernova (SN) explosions are crucial engines driving the evolution of galaxies by shock heating ... more Supernova (SN) explosions are crucial engines driving the evolution of galaxies by shock heating gas, increasing the metallicity, creating dust, and accelerating energetic particles. In 2012 we used the Atacama Large Millimeter/Submillimeter Array to observe SN 1987A, one of the best-observed supernovae since the invention of the telescope. We present spatially resolved images at 450 µm, 870 µm, 1.4 mm, and 2.8 mm, an important transition wavelength range. Longer wavelength emission is dominated by synchrotron radiation from shock-accelerated particles, shorter wavelengths by emission from the largest mass of dust measured in a supernova remnant (>0.2 M). For the first time we show unambiguously that this dust has formed in the inner ejecta (the cold remnants of the exploded star's core). The dust emission is concentrated to the center of the remnant, so the dust has not yet been affected by the shocks. If a significant fraction survives, and if SN 1987A is typical, supernovae are important cosmological dust producers.
Astronomy and Astrophysics Supplement Series, 1997
Using the Gemini South 8m telescope, we obtained high resolution 11.7 and 18.3 µm mid-IR images o... more Using the Gemini South 8m telescope, we obtained high resolution 11.7 and 18.3 µm mid-IR images of SN 1987A on day 6526 since the explosion. All the emission arises from the equatorial ring. Nearly contemporaneous spectra obtained at 5–38 µm with the Spitzer Space Telescope show that this is thermal emission from silicate dust that condensed out in the red giant wind of the progenitor star. The dust temperature is 166 +18 −12 K, and the emitting dust mass is (2.6 +2.0
Using the Gemini South 8m telescope, we obtained high resolution 11.7 and 18.3 μm mid-IR images o... more Using the Gemini South 8m telescope, we obtained high resolution 11.7 and 18.3 μm mid-IR images of SN 1987A on day 6526 since the explosion. All the emission arises from the equatorial ring. Nearly contemporaneous spectra obtained at 5–38 μm with the Spitzer Space Telescope show that this is thermal emission from silicate dust that condensed out in the red giant wind of the progenitor star. The dust temperature is 166 −12 K, and the emitting dust mass is (2.6 +2.0 −1.4) × 10 −6 M⊙. Comparison of the Gemini 11.7 μm image with Chandra X-ray images, Hubble GEPI, Observatoire de Paris, Site de Meudon, 5 Place Jules Janssen, F-92195, Meudon, France; Patrice.Bouchet@obspm.fr Cerro Tololo Inter-American Observatory (CTIO), National Optical Astronomy Observatory (NOAO), Casilla 603, La Serena, Chile; CTIO is operated by the Association of Universities for Research in Astronomy (AURA), Inc. under cooperative agreement with the National Science Foundation. Observational Cosmology lab., Code 6...
Discoveries and Research Prospects from 6- to 10-Meter-Class Telescopes II, 2003
Phoenix, a high resolution near-infrared spectrograph build by NOAO, was first used on the Gemini... more Phoenix, a high resolution near-infrared spectrograph build by NOAO, was first used on the Gemini South telescope in December 2001. Previously on the Kitt Peak 2.1 and 4 meter telescopes, Phoenix received a new detector, as well as modified refrigeration, mounting, and handling equipment, prior to being sent to Gemini South. Using a two-pixel slit the resolution is ~75,000, making
Monthly Notices of the Royal Astronomical Society, Oct 30, 1990
ABSTRACT
The Messenger, Sep 1, 1986
ABSTRACT
Paris Vii Universite 1990, 1990
Astronomy and Astrophysics, May 30, 1993
ABSTRACT
ABSTRACT The basic features and astrophysics of supernovae of types Ia, Ib, and II and of SNRs ar... more ABSTRACT The basic features and astrophysics of supernovae of types Ia, Ib, and II and of SNRs are discussed, summarizing the results of recent ground-based and space observations obtained at different wavelengths. Typical data are presented in graphs and sample images, and consideration is given to their implications for shock heating by the initial explosion, radioactive energy input, circumstellar interaction, and pulsar energy input. SNRs described include Tycho's remnant, Kepler's remnant, the Cyg loop, Pup A, the Crab Nebula, the Vela and Crab pulsars, and 0540-69.3 in the LMC. The need for high-spatial-resolution IR and X-ray spectra of these objects is indicated.
We will use the SPITZER to continue the ongoing monitoring of SN1987A, the youngest supernova rem... more We will use the SPITZER to continue the ongoing monitoring of SN1987A, the youngest supernova remnant that is undergoing noticable evolutionary changes during the lifetime of the Great Observatories. At infrared wavelengths SN1987A provides a unique complimentary view of the interaction of the SN blast wave with the equatorial ring (ER). Dust in theÊ ERÊ is being swept up by
Quasi-simultaneous multifrequency observations from radio to X-rays of the bright quasar 3C273 fo... more Quasi-simultaneous multifrequency observations from radio to X-rays of the bright quasar 3C273 for several epochs between December 1983 and March 1986 are presented. The light curves in the different wavebands and the overall spectral energy distribution are analyzed. The NIR and optical fluxes showed small variations during the period considered, whereas the hard X-ray flux decreased by a factor of about 2 at the beginning of 1984, remained low during 1984-1985, and increased again by about 40 percent at the beginning of 1986. The soft X-ray flux varied several times by 20-40 percent, with no apparent underlying trend. In the submillimeter region, the flux remained constant during 1984, decreased in 1985, and again in 1986 to reach its lowest known level. The variations occurred at different epochs in the different wavebands, requiring the presence of different, although possibly related, emission components dominating the flux in the different spectral regions.
The Astrophysical Journal, 2020
Spitzerʼs final Infrared Array Camera observations of SN 1987A show the 3.6 and 4.5 μm emission f... more Spitzerʼs final Infrared Array Camera observations of SN 1987A show the 3.6 and 4.5 μm emission from the equatorial ring (ER) continues a period of steady decline. Deconvolution of the images reveals that the emission is dominated by the ring, not the ejecta, and is brightest on the west side. Decomposition of the marginally resolved emission also confirms this, and shows that the west side of the ER has been brightening relative to the other portions of the ER. The infrared morphological changes resemble those seen in both the soft X-ray emission and the optical emission. The integrated ER light curves at 3.6 and 4.5 μm are more similar to the optical light curves than the soft X-ray light curve, though differences would be expected if dust is responsible for this emission and its destruction is rapid. Future observations with the James Webb Space Telescope will continue to monitor the ER evolution, and will reveal the true spectrum and nature of the material responsible for the broadband emission at 3.6 and 4.5 μm. The present observations also serendipitously reveal a nearby variable source, subsequently identified as a Be star, that has gone through a multiyear outburst during the course of these observations.
Astronomy & Astrophysics, 1999
We present ISO observations made between 2.5 and 180 mu m of the nearby G0V dwarf HD 207129 taken... more We present ISO observations made between 2.5 and 180 mu m of the nearby G0V dwarf HD 207129 taken as part of a large survey of nearby main-sequence stars in search of debris discs. HD 207129 emits radiation in excess of the photospheric flux density between at least 60 and 180 mu m. The infrared excess is explained by a
The Astrophysical Journal, 2012
We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2... more We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M, and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on the Hubble Space Telescope. This dataset provides unique spectral time series down to 2000 Å. Significant diversity is seen in the near-maximum-light spectra (∼ 2000-3500 Å) for this small sample. The corresponding photometric data, together with archival data from Swift Ultraviolet/Optical Telescope observations, provide further evidence of increased dispersion in the UV emission with respect to the optical. The peak luminosities measured in the uvw1/F250W filter are found to correlate with the B-band light-curve shape parameter ∆m 15 (B), but with much larger scatter relative to the correlation in the broad-band B band (e.g., ∼ 0.4 mag versus ∼ 0.2 mag for those with 0.8 < ∆m 15 (B) < 1.7 mag). SN 2004dt is found as an outlier of this correlation (at > 3σ), being brighter than normal SNe Ia such as SN 2005cf by ∼ 0.9 mag and ∼ 2.0 mag in the uvw1/F250W and uvm2/F220W filters, respectively. We show that different progenitor metallicity or line-expansion velocities alone cannot explain such a large discrepancy. Viewing-angle effects, such as due to an asymmetric explosion, may have a significant influence on the flux emitted in the UV region. Detailed modeling is needed to disentangle and quantify the above effects.
The results on Vega-like stars obtained with ISO are discussed. We find that the incidence of Veg... more The results on Vega-like stars obtained with ISO are discussed. We find that the incidence of Vega-like disks is approximately 21% on average, with some dependency upon the spectral type. While young stars do more frequently show disks than old stars, there is no clear trend in the amount of dust seen at different ages. We also discuss the discovery
The Astrophysical Journal, 2014
Supernova (SN) explosions are crucial engines driving the evolution of galaxies by shock heating ... more Supernova (SN) explosions are crucial engines driving the evolution of galaxies by shock heating gas, increasing the metallicity, creating dust, and accelerating energetic particles. In 2012 we used the Atacama Large Millimeter/Submillimeter Array to observe SN 1987A, one of the best-observed supernovae since the invention of the telescope. We present spatially resolved images at 450 µm, 870 µm, 1.4 mm, and 2.8 mm, an important transition wavelength range. Longer wavelength emission is dominated by synchrotron radiation from shock-accelerated particles, shorter wavelengths by emission from the largest mass of dust measured in a supernova remnant (>0.2 M). For the first time we show unambiguously that this dust has formed in the inner ejecta (the cold remnants of the exploded star's core). The dust emission is concentrated to the center of the remnant, so the dust has not yet been affected by the shocks. If a significant fraction survives, and if SN 1987A is typical, supernovae are important cosmological dust producers.
Astronomy and Astrophysics Supplement Series, 1997
Using the Gemini South 8m telescope, we obtained high resolution 11.7 and 18.3 µm mid-IR images o... more Using the Gemini South 8m telescope, we obtained high resolution 11.7 and 18.3 µm mid-IR images of SN 1987A on day 6526 since the explosion. All the emission arises from the equatorial ring. Nearly contemporaneous spectra obtained at 5–38 µm with the Spitzer Space Telescope show that this is thermal emission from silicate dust that condensed out in the red giant wind of the progenitor star. The dust temperature is 166 +18 −12 K, and the emitting dust mass is (2.6 +2.0
Using the Gemini South 8m telescope, we obtained high resolution 11.7 and 18.3 μm mid-IR images o... more Using the Gemini South 8m telescope, we obtained high resolution 11.7 and 18.3 μm mid-IR images of SN 1987A on day 6526 since the explosion. All the emission arises from the equatorial ring. Nearly contemporaneous spectra obtained at 5–38 μm with the Spitzer Space Telescope show that this is thermal emission from silicate dust that condensed out in the red giant wind of the progenitor star. The dust temperature is 166 −12 K, and the emitting dust mass is (2.6 +2.0 −1.4) × 10 −6 M⊙. Comparison of the Gemini 11.7 μm image with Chandra X-ray images, Hubble GEPI, Observatoire de Paris, Site de Meudon, 5 Place Jules Janssen, F-92195, Meudon, France; Patrice.Bouchet@obspm.fr Cerro Tololo Inter-American Observatory (CTIO), National Optical Astronomy Observatory (NOAO), Casilla 603, La Serena, Chile; CTIO is operated by the Association of Universities for Research in Astronomy (AURA), Inc. under cooperative agreement with the National Science Foundation. Observational Cosmology lab., Code 6...
Discoveries and Research Prospects from 6- to 10-Meter-Class Telescopes II, 2003
Phoenix, a high resolution near-infrared spectrograph build by NOAO, was first used on the Gemini... more Phoenix, a high resolution near-infrared spectrograph build by NOAO, was first used on the Gemini South telescope in December 2001. Previously on the Kitt Peak 2.1 and 4 meter telescopes, Phoenix received a new detector, as well as modified refrigeration, mounting, and handling equipment, prior to being sent to Gemini South. Using a two-pixel slit the resolution is ~75,000, making
Monthly Notices of the Royal Astronomical Society, Oct 30, 1990
ABSTRACT
The Messenger, Sep 1, 1986
ABSTRACT
Paris Vii Universite 1990, 1990
Astronomy and Astrophysics, May 30, 1993
ABSTRACT
ABSTRACT The basic features and astrophysics of supernovae of types Ia, Ib, and II and of SNRs ar... more ABSTRACT The basic features and astrophysics of supernovae of types Ia, Ib, and II and of SNRs are discussed, summarizing the results of recent ground-based and space observations obtained at different wavelengths. Typical data are presented in graphs and sample images, and consideration is given to their implications for shock heating by the initial explosion, radioactive energy input, circumstellar interaction, and pulsar energy input. SNRs described include Tycho's remnant, Kepler's remnant, the Cyg loop, Pup A, the Crab Nebula, the Vela and Crab pulsars, and 0540-69.3 in the LMC. The need for high-spatial-resolution IR and X-ray spectra of these objects is indicated.
We will use the SPITZER to continue the ongoing monitoring of SN1987A, the youngest supernova rem... more We will use the SPITZER to continue the ongoing monitoring of SN1987A, the youngest supernova remnant that is undergoing noticable evolutionary changes during the lifetime of the Great Observatories. At infrared wavelengths SN1987A provides a unique complimentary view of the interaction of the SN blast wave with the equatorial ring (ER). Dust in theÊ ERÊ is being swept up by