The Experts below are selected from a list of 273 Experts worldwide ranked by ideXlab platform

Deborah Levine - One of the best experts on this subject based on the ideXlab platform.

  • Strong water absorption in the dayside Emission Spectrum of the planet HD 189733b
    Nature, 2008
    Co-Authors: Carl J. Grillmair, Adam Burrows, David Charbonneau, Lee Armus, John Stauffer, Victoria Meadows, Jeffrey Van Cleve, Kaspar Von Braun, Deborah Levine
    Abstract:

    Recent observations of the extrasolar planet HD 189733b did not reveal the presence of water in the Emission Spectrum of the planet^ 1 . Yet models of such ‘hot-Jupiter’ planets predict an abundance of atmospheric water vapour^ 2 . Validating and constraining these models is crucial to understanding the physics and chemistry of planetary atmospheres in extreme environments. Indications of the presence of water in the atmosphere of HD 189733b have recently been found in transmission spectra^ 3 , 4 , where the planet’s atmosphere selectively absorbs the light of the parent star, and in broadband photometry^ 5 . Here we report the detection of strong water absorption in a high-signal-to-noise, mid-infrared Emission Spectrum of the planet itself. We find both a strong downturn in the flux ratio below 10 µm and discrete spectral features that are characteristic of strong absorption by water vapour. The differences between these and previous observations are significant and admit the possibility that predicted planetary-scale dynamical weather structures^ 6 may alter the Emission Spectrum over time. Models that match the observed Spectrum and the broadband photometry suggest that heat redistribution from the dayside to the nightside is weak. Reconciling this with the high nightside temperature^ 7 will require a better understanding of atmospheric circulation or possible additional energy sources. A long-term series of observations with the Spitzer Space Telescope has generated the highest quality Spectrum so far obtained for an extrasolar planet. Previous spectra of the 'hot Jupiter' HD 189733b did not detect the predicted abundance of water vapour in the atmosphere, but the new data reveal strong water absorption in a mid-infrared Emission Spectrum. The differences between these and the earlier observations point to the possibility that predicted planetary-scale dynamical weather structures might alter the Emission Spectrum over time. Indications of the presence of water in the atmosphere of the planet HD 189733b have recently been found in transmission spectra. This paper reports the detection of strong water absorption in a high signal-to-noise, mid-infrared Emission Spectrum of the planet itself. The differences between these and previous observations are significant and admit the possibility that predicted planetary-scale dynamical weather structures might alter the Emission Spectrum over time.

  • Strong water absorption in the dayside Emission Spectrum of the planet HD 189733b
    Nature, 2008
    Co-Authors: Carl J. Grillmair, Adam Burrows, David Charbonneau, Lee Armus, John R. Stauffer, Victoria S. Meadows, Jeffrey Van Cleve, Kaspar Von Braun, Deborah Levine
    Abstract:

    Recent observations of the extrasolar planet HD189733b did not reveal the presence of water in the Emission Spectrum of the planet^1. Yet models of such 'hot-Jupiter' planets predict an abundance of atmospheric water vapour^2. Validating and constraining these models is crucial to understanding the physics and chemistry of planetary atmospheres in extreme environments. Indications of the presence of water in the atmosphere of HD189733b have recently been found in transmission spectra^3,4, where the planet's atmosphere selectively absorbs the light of the parent star, and in broadband photometry^5. Here we report the detection of strong water absorption in a high- signal- to- noise, mid- infrared Emission Spectrumof the planet itself. We find both a strong downturn in the flux ratio below 10 µm and discrete spectral features that are characteristic of strong absorption by water vapour. The differences between these and previous observations are significant and admit the possibility that predicted planetary- scale dynamical weather structures^6 may alter the Emission Spectrum over time. Models that match the observed Spectrum and the broadband photometry suggest that heat redistribution from the dayside to the nightside is weak. Reconciling this with the high nightside temperature^7 will require a better understanding of atmospheric circulation or possible additional energy sources.

Adam Burrows - One of the best experts on this subject based on the ideXlab platform.

  • detection of a temperature inversion in the broadband infrared Emission Spectrum of tres 4
    The Astrophysical Journal, 2009
    Co-Authors: Heather A Knutson, Adam Burrows, David Charbonneau, Francis T Odonovan, Georgi Mandushev
    Abstract:

    We estimate the strength of the bandpass-integrated thermal Emission from the extrasolar planet TrES-4 at 3.6, 4.5, 5.8, and 8.0 μ using the Infrared Array Camera on the Spitzer Space Telescope. We find relative eclipse depths of 0.137% ± 0.011%, 0.148% ± 0.016%, 0.261% ± 0.059%, and 0.318% ± 0.044% in these four bandpasses, respectively. We also place a 2σ upper limit of 0.37% on the depth of the secondary eclipse in the 16 μ IRS peak-up array. These eclipse depths reveal that TrES-4 has an Emission Spectrum similar to that of HD 209458b, which requires the presence of water Emission bands created by a thermal inversion layer high in the atmosphere in order to explain the observed features. TrES-4 receives more radiation from its star than HD 209458b and has a correspondingly higher effective temperature, therefore the presence of a temperature inversion in this planet's atmosphere lends support to the idea that inversions might be correlated with the irradiance received by the planet. We find no evidence for any offset in the timing of the secondary eclipse, and place a 3σ upper limit of |ecos(ω)| < 0.0058, where e is the planet's orbital eccentricity and ω is the argument of pericenter. From this we conclude that tidal heating from ongoing orbital circularization is unlikely to be the explanation for TrES-4's inflated radius.

  • Strong water absorption in the dayside Emission Spectrum of the planet HD 189733b
    Nature, 2008
    Co-Authors: Carl J. Grillmair, Adam Burrows, David Charbonneau, Lee Armus, John Stauffer, Victoria Meadows, Jeffrey Van Cleve, Kaspar Von Braun, Deborah Levine
    Abstract:

    Recent observations of the extrasolar planet HD 189733b did not reveal the presence of water in the Emission Spectrum of the planet^ 1 . Yet models of such ‘hot-Jupiter’ planets predict an abundance of atmospheric water vapour^ 2 . Validating and constraining these models is crucial to understanding the physics and chemistry of planetary atmospheres in extreme environments. Indications of the presence of water in the atmosphere of HD 189733b have recently been found in transmission spectra^ 3 , 4 , where the planet’s atmosphere selectively absorbs the light of the parent star, and in broadband photometry^ 5 . Here we report the detection of strong water absorption in a high-signal-to-noise, mid-infrared Emission Spectrum of the planet itself. We find both a strong downturn in the flux ratio below 10 µm and discrete spectral features that are characteristic of strong absorption by water vapour. The differences between these and previous observations are significant and admit the possibility that predicted planetary-scale dynamical weather structures^ 6 may alter the Emission Spectrum over time. Models that match the observed Spectrum and the broadband photometry suggest that heat redistribution from the dayside to the nightside is weak. Reconciling this with the high nightside temperature^ 7 will require a better understanding of atmospheric circulation or possible additional energy sources. A long-term series of observations with the Spitzer Space Telescope has generated the highest quality Spectrum so far obtained for an extrasolar planet. Previous spectra of the 'hot Jupiter' HD 189733b did not detect the predicted abundance of water vapour in the atmosphere, but the new data reveal strong water absorption in a mid-infrared Emission Spectrum. The differences between these and the earlier observations point to the possibility that predicted planetary-scale dynamical weather structures might alter the Emission Spectrum over time. Indications of the presence of water in the atmosphere of the planet HD 189733b have recently been found in transmission spectra. This paper reports the detection of strong water absorption in a high signal-to-noise, mid-infrared Emission Spectrum of the planet itself. The differences between these and previous observations are significant and admit the possibility that predicted planetary-scale dynamical weather structures might alter the Emission Spectrum over time.

  • Strong water absorption in the dayside Emission Spectrum of the planet HD 189733b
    Nature, 2008
    Co-Authors: Carl J. Grillmair, Adam Burrows, David Charbonneau, Lee Armus, John R. Stauffer, Victoria S. Meadows, Jeffrey Van Cleve, Kaspar Von Braun, Deborah Levine
    Abstract:

    Recent observations of the extrasolar planet HD189733b did not reveal the presence of water in the Emission Spectrum of the planet^1. Yet models of such 'hot-Jupiter' planets predict an abundance of atmospheric water vapour^2. Validating and constraining these models is crucial to understanding the physics and chemistry of planetary atmospheres in extreme environments. Indications of the presence of water in the atmosphere of HD189733b have recently been found in transmission spectra^3,4, where the planet's atmosphere selectively absorbs the light of the parent star, and in broadband photometry^5. Here we report the detection of strong water absorption in a high- signal- to- noise, mid- infrared Emission Spectrumof the planet itself. We find both a strong downturn in the flux ratio below 10 µm and discrete spectral features that are characteristic of strong absorption by water vapour. The differences between these and previous observations are significant and admit the possibility that predicted planetary- scale dynamical weather structures^6 may alter the Emission Spectrum over time. Models that match the observed Spectrum and the broadband photometry suggest that heat redistribution from the dayside to the nightside is weak. Reconciling this with the high nightside temperature^7 will require a better understanding of atmospheric circulation or possible additional energy sources.

  • detection of a temperature inversion in the broadband infrared Emission Spectrum of tres 4
    arXiv: Astrophysics, 2008
    Co-Authors: Heather A Knutson, Adam Burrows, David Charbonneau, Francis T Odonovan, Georgi Mandushev
    Abstract:

    We estimate the strength of the bandpass-integrated thermal Emission from the extrasolar planet TrES-4 at 3.6, 4.5, 5.8, and 8.0 micron using the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. We find relative eclipse depths of 0.137 +/- 0.011%, 0.148 +/- 0.016%, 0.261 +/- 0.059%, and 0.318 +/- 0.044% in these four bandpasses, respectively. We also place a 2 sigma upper limit of 0.37% on the depth of the secondary eclipse in the 16 micron IRS peak-up array. These eclipse depths reveal that TrES-4 has an Emission Spectrum similar to that of HD 209458b, which requires the presence of water Emission bands created by an thermal inversion layer high in the atmosphere in order to explain the observed features. TrES-4 receives more radiation from its star than HD 209458b and has a correspondingly higher effective temperature, therefore the presence of a temperature inversion in this planet's atmosphere lends support to the idea that inversions might be correlated with the irradiance received by the planet. We find no evidence for any offset in the timing of the secondary eclipse, and place a 3 sigma upper limit of |ecos(omega)|<0.0058 where e is the planet's orbital eccentricity and omega is the argument of pericenter. From this we conclude that tidal heating from ongoing orbital circulatization is unlikely to be the explanation for TrES-4's inflated radius.

  • the 3 6 8 0 μm broadband Emission Spectrum of hd 209458b evidence for an atmospheric temperature inversion
    The Astrophysical Journal, 2008
    Co-Authors: Heather A Knutson, Adam Burrows, David Charbonneau, Lori E Allen, Thomas S Megeath
    Abstract:

    We estimate the strength of the bandpass-integrated thermal Emission from the extrasolar planet HD 209458b at 3.6, 4.5, 5.8, and 8.0 μm using the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. We observe a single secondary eclipse simultaneously in all four bandpasses and find relative eclipse depths of 0.00094 ± 0.00009, 0.00213 ± 0.00015, 0.00301 ± 0.00043, and 0.00240 ± 0.00026, respectively. These eclipse depths reveal that the shape of the inferred Emission Spectrum for the planet differs significantly from the predictions of standard atmosphere models; instead, the most plausible explanation would require the presence of an inversion layer high in the atmosphere leading to significant water Emission in the 4.5 and 5.8 μm bandpasses. This is the first clear indication of such a temperature inversion in the atmosphere of a hot Jupiter, as previous observations of other planets appeared to be in reasonably good agreement with the predictions of models without such an inversion layer.

David Charbonneau - One of the best experts on this subject based on the ideXlab platform.

  • detection of a temperature inversion in the broadband infrared Emission Spectrum of tres 4
    The Astrophysical Journal, 2009
    Co-Authors: Heather A Knutson, Adam Burrows, David Charbonneau, Francis T Odonovan, Georgi Mandushev
    Abstract:

    We estimate the strength of the bandpass-integrated thermal Emission from the extrasolar planet TrES-4 at 3.6, 4.5, 5.8, and 8.0 μ using the Infrared Array Camera on the Spitzer Space Telescope. We find relative eclipse depths of 0.137% ± 0.011%, 0.148% ± 0.016%, 0.261% ± 0.059%, and 0.318% ± 0.044% in these four bandpasses, respectively. We also place a 2σ upper limit of 0.37% on the depth of the secondary eclipse in the 16 μ IRS peak-up array. These eclipse depths reveal that TrES-4 has an Emission Spectrum similar to that of HD 209458b, which requires the presence of water Emission bands created by a thermal inversion layer high in the atmosphere in order to explain the observed features. TrES-4 receives more radiation from its star than HD 209458b and has a correspondingly higher effective temperature, therefore the presence of a temperature inversion in this planet's atmosphere lends support to the idea that inversions might be correlated with the irradiance received by the planet. We find no evidence for any offset in the timing of the secondary eclipse, and place a 3σ upper limit of |ecos(ω)| < 0.0058, where e is the planet's orbital eccentricity and ω is the argument of pericenter. From this we conclude that tidal heating from ongoing orbital circularization is unlikely to be the explanation for TrES-4's inflated radius.

  • Strong water absorption in the dayside Emission Spectrum of the planet HD 189733b
    Nature, 2008
    Co-Authors: Carl J. Grillmair, Adam Burrows, David Charbonneau, Lee Armus, John Stauffer, Victoria Meadows, Jeffrey Van Cleve, Kaspar Von Braun, Deborah Levine
    Abstract:

    Recent observations of the extrasolar planet HD 189733b did not reveal the presence of water in the Emission Spectrum of the planet^ 1 . Yet models of such ‘hot-Jupiter’ planets predict an abundance of atmospheric water vapour^ 2 . Validating and constraining these models is crucial to understanding the physics and chemistry of planetary atmospheres in extreme environments. Indications of the presence of water in the atmosphere of HD 189733b have recently been found in transmission spectra^ 3 , 4 , where the planet’s atmosphere selectively absorbs the light of the parent star, and in broadband photometry^ 5 . Here we report the detection of strong water absorption in a high-signal-to-noise, mid-infrared Emission Spectrum of the planet itself. We find both a strong downturn in the flux ratio below 10 µm and discrete spectral features that are characteristic of strong absorption by water vapour. The differences between these and previous observations are significant and admit the possibility that predicted planetary-scale dynamical weather structures^ 6 may alter the Emission Spectrum over time. Models that match the observed Spectrum and the broadband photometry suggest that heat redistribution from the dayside to the nightside is weak. Reconciling this with the high nightside temperature^ 7 will require a better understanding of atmospheric circulation or possible additional energy sources. A long-term series of observations with the Spitzer Space Telescope has generated the highest quality Spectrum so far obtained for an extrasolar planet. Previous spectra of the 'hot Jupiter' HD 189733b did not detect the predicted abundance of water vapour in the atmosphere, but the new data reveal strong water absorption in a mid-infrared Emission Spectrum. The differences between these and the earlier observations point to the possibility that predicted planetary-scale dynamical weather structures might alter the Emission Spectrum over time. Indications of the presence of water in the atmosphere of the planet HD 189733b have recently been found in transmission spectra. This paper reports the detection of strong water absorption in a high signal-to-noise, mid-infrared Emission Spectrum of the planet itself. The differences between these and previous observations are significant and admit the possibility that predicted planetary-scale dynamical weather structures might alter the Emission Spectrum over time.

  • Strong water absorption in the dayside Emission Spectrum of the planet HD 189733b
    Nature, 2008
    Co-Authors: Carl J. Grillmair, Adam Burrows, David Charbonneau, Lee Armus, John R. Stauffer, Victoria S. Meadows, Jeffrey Van Cleve, Kaspar Von Braun, Deborah Levine
    Abstract:

    Recent observations of the extrasolar planet HD189733b did not reveal the presence of water in the Emission Spectrum of the planet^1. Yet models of such 'hot-Jupiter' planets predict an abundance of atmospheric water vapour^2. Validating and constraining these models is crucial to understanding the physics and chemistry of planetary atmospheres in extreme environments. Indications of the presence of water in the atmosphere of HD189733b have recently been found in transmission spectra^3,4, where the planet's atmosphere selectively absorbs the light of the parent star, and in broadband photometry^5. Here we report the detection of strong water absorption in a high- signal- to- noise, mid- infrared Emission Spectrumof the planet itself. We find both a strong downturn in the flux ratio below 10 µm and discrete spectral features that are characteristic of strong absorption by water vapour. The differences between these and previous observations are significant and admit the possibility that predicted planetary- scale dynamical weather structures^6 may alter the Emission Spectrum over time. Models that match the observed Spectrum and the broadband photometry suggest that heat redistribution from the dayside to the nightside is weak. Reconciling this with the high nightside temperature^7 will require a better understanding of atmospheric circulation or possible additional energy sources.

  • detection of a temperature inversion in the broadband infrared Emission Spectrum of tres 4
    arXiv: Astrophysics, 2008
    Co-Authors: Heather A Knutson, Adam Burrows, David Charbonneau, Francis T Odonovan, Georgi Mandushev
    Abstract:

    We estimate the strength of the bandpass-integrated thermal Emission from the extrasolar planet TrES-4 at 3.6, 4.5, 5.8, and 8.0 micron using the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. We find relative eclipse depths of 0.137 +/- 0.011%, 0.148 +/- 0.016%, 0.261 +/- 0.059%, and 0.318 +/- 0.044% in these four bandpasses, respectively. We also place a 2 sigma upper limit of 0.37% on the depth of the secondary eclipse in the 16 micron IRS peak-up array. These eclipse depths reveal that TrES-4 has an Emission Spectrum similar to that of HD 209458b, which requires the presence of water Emission bands created by an thermal inversion layer high in the atmosphere in order to explain the observed features. TrES-4 receives more radiation from its star than HD 209458b and has a correspondingly higher effective temperature, therefore the presence of a temperature inversion in this planet's atmosphere lends support to the idea that inversions might be correlated with the irradiance received by the planet. We find no evidence for any offset in the timing of the secondary eclipse, and place a 3 sigma upper limit of |ecos(omega)|<0.0058 where e is the planet's orbital eccentricity and omega is the argument of pericenter. From this we conclude that tidal heating from ongoing orbital circulatization is unlikely to be the explanation for TrES-4's inflated radius.

  • the 3 6 8 0 μm broadband Emission Spectrum of hd 209458b evidence for an atmospheric temperature inversion
    The Astrophysical Journal, 2008
    Co-Authors: Heather A Knutson, Adam Burrows, David Charbonneau, Lori E Allen, Thomas S Megeath
    Abstract:

    We estimate the strength of the bandpass-integrated thermal Emission from the extrasolar planet HD 209458b at 3.6, 4.5, 5.8, and 8.0 μm using the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. We observe a single secondary eclipse simultaneously in all four bandpasses and find relative eclipse depths of 0.00094 ± 0.00009, 0.00213 ± 0.00015, 0.00301 ± 0.00043, and 0.00240 ± 0.00026, respectively. These eclipse depths reveal that the shape of the inferred Emission Spectrum for the planet differs significantly from the predictions of standard atmosphere models; instead, the most plausible explanation would require the presence of an inversion layer high in the atmosphere leading to significant water Emission in the 4.5 and 5.8 μm bandpasses. This is the first clear indication of such a temperature inversion in the atmosphere of a hot Jupiter, as previous observations of other planets appeared to be in reasonably good agreement with the predictions of models without such an inversion layer.

Carl J. Grillmair - One of the best experts on this subject based on the ideXlab platform.

  • Strong water absorption in the dayside Emission Spectrum of the planet HD 189733b
    Nature, 2008
    Co-Authors: Carl J. Grillmair, Adam Burrows, David Charbonneau, Lee Armus, John Stauffer, Victoria Meadows, Jeffrey Van Cleve, Kaspar Von Braun, Deborah Levine
    Abstract:

    Recent observations of the extrasolar planet HD 189733b did not reveal the presence of water in the Emission Spectrum of the planet^ 1 . Yet models of such ‘hot-Jupiter’ planets predict an abundance of atmospheric water vapour^ 2 . Validating and constraining these models is crucial to understanding the physics and chemistry of planetary atmospheres in extreme environments. Indications of the presence of water in the atmosphere of HD 189733b have recently been found in transmission spectra^ 3 , 4 , where the planet’s atmosphere selectively absorbs the light of the parent star, and in broadband photometry^ 5 . Here we report the detection of strong water absorption in a high-signal-to-noise, mid-infrared Emission Spectrum of the planet itself. We find both a strong downturn in the flux ratio below 10 µm and discrete spectral features that are characteristic of strong absorption by water vapour. The differences between these and previous observations are significant and admit the possibility that predicted planetary-scale dynamical weather structures^ 6 may alter the Emission Spectrum over time. Models that match the observed Spectrum and the broadband photometry suggest that heat redistribution from the dayside to the nightside is weak. Reconciling this with the high nightside temperature^ 7 will require a better understanding of atmospheric circulation or possible additional energy sources. A long-term series of observations with the Spitzer Space Telescope has generated the highest quality Spectrum so far obtained for an extrasolar planet. Previous spectra of the 'hot Jupiter' HD 189733b did not detect the predicted abundance of water vapour in the atmosphere, but the new data reveal strong water absorption in a mid-infrared Emission Spectrum. The differences between these and the earlier observations point to the possibility that predicted planetary-scale dynamical weather structures might alter the Emission Spectrum over time. Indications of the presence of water in the atmosphere of the planet HD 189733b have recently been found in transmission spectra. This paper reports the detection of strong water absorption in a high signal-to-noise, mid-infrared Emission Spectrum of the planet itself. The differences between these and previous observations are significant and admit the possibility that predicted planetary-scale dynamical weather structures might alter the Emission Spectrum over time.

  • Strong water absorption in the dayside Emission Spectrum of the planet HD 189733b
    Nature, 2008
    Co-Authors: Carl J. Grillmair, Adam Burrows, David Charbonneau, Lee Armus, John R. Stauffer, Victoria S. Meadows, Jeffrey Van Cleve, Kaspar Von Braun, Deborah Levine
    Abstract:

    Recent observations of the extrasolar planet HD189733b did not reveal the presence of water in the Emission Spectrum of the planet^1. Yet models of such 'hot-Jupiter' planets predict an abundance of atmospheric water vapour^2. Validating and constraining these models is crucial to understanding the physics and chemistry of planetary atmospheres in extreme environments. Indications of the presence of water in the atmosphere of HD189733b have recently been found in transmission spectra^3,4, where the planet's atmosphere selectively absorbs the light of the parent star, and in broadband photometry^5. Here we report the detection of strong water absorption in a high- signal- to- noise, mid- infrared Emission Spectrumof the planet itself. We find both a strong downturn in the flux ratio below 10 µm and discrete spectral features that are characteristic of strong absorption by water vapour. The differences between these and previous observations are significant and admit the possibility that predicted planetary- scale dynamical weather structures^6 may alter the Emission Spectrum over time. Models that match the observed Spectrum and the broadband photometry suggest that heat redistribution from the dayside to the nightside is weak. Reconciling this with the high nightside temperature^7 will require a better understanding of atmospheric circulation or possible additional energy sources.

Heather A Knutson - One of the best experts on this subject based on the ideXlab platform.

  • evidence for atmospheric cold trap processes in the noninverted Emission Spectrum of kepler 13ab using hst wfc3
    The Astronomical Journal, 2017
    Co-Authors: Thomas G Beatty, Heather A Knutson, Nikku Madhusudhan, Angelos Tsiaras, Ming Zhao, Ronald L Gilliland, Avi Shporer, Jason T Wright
    Abstract:

    We observed two eclipses of the Kepler-13A planetary system, on UT 2014 April 28 and UT 2014 October 13, in the near-infrared using Wide Field Camera 3 on the Hubble Space Telescope. By using the nearby binary stars Kepler-13BC as a reference, we were able to create a differential light curve for Kepler-13A that had little of the systematics typically present in HST/WFC3 spectrophotometry. We measure a broadband (1.1–1.65 μm) eclipse depth of 734 ± 28 ppm and are able to measure the Emission Spectrum of the planet at R ≈ 50 with an average precision of 70 ppm. We find that Kepler-13Ab possesses a noninverted, monotonically decreasing vertical temperature profile. We exclude an isothermal profile and an inverted profile at more than 3σ. We also find that the dayside Emission of Kepler-13Ab appears generally similar to an isolated M7 brown dwarf at a similar effective temperature. Due to the relatively high mass and surface gravity of Kepler-13Ab, we suggest that the apparent lack of an inversion is due to cold-trap processes in the planet's atmosphere. Using a toy model for where cold traps should inhibit inversions, as well as observations of other planets in this temperature range with measured Emission spectra, we argue that with more detailed modeling and more observations we may be able to place useful constraints on the size of condensates on the daysides of hot Jupiters.

  • evidence for atmospheric cold trap processes in the noninverted Emission Spectrum of kepler 13ab using hst wfc3
    arXiv: Earth and Planetary Astrophysics, 2016
    Co-Authors: Thomas G Beatty, Heather A Knutson, Nikku Madhusudhan, Angelos Tsiaras, Ming Zhao, Ronald L Gilliland, Avi Shporer, Jason T Wright
    Abstract:

    We observed two eclipses of the Kepler-13A planetary system, on UT 2014 April 28 and UT 2014 October 13, in the near-infrared using Wide Field Camera 3 on the Hubble Space Telescope. By using the nearby binary stars Kepler-13BC as a reference, we were able to create a differential light curve for Kepler-13A that had little of the systematics typically present in HST/WFC3 spectrophotometry. We measure a broadband (1.1$\mu$m to 1.65$\mu$m) eclipse depth of $734\pm28$ ppm, and are able to measure the Emission Spectrum of the planet at $R\approx50$ with an average precision of 70 ppm. We find that Kepler-13Ab possesses a noninverted, monotonically decreasing vertical temperature profile. We exclude an isothermal profile and an inverted profile at more than 3$\sigma$. We also find that the dayside Emission of Kepler-13Ab appears generally similar to an isolated M7 brown dwarf at a similar effective temperature. Due to the relatively high mass and surface gravity of Kepler-13Ab, we suggest that the apparent lack of an inversion is due to cold-trap processes in the planet's atmosphere. Using a toy model for where cold-traps should inhibit inversions, and observations of other planets in this temperature range with measured Emission spectra, we argue that with more detailed modeling and more observations we may be able to place useful constraints on the size of condensates on the daysides of hot Jupiters.

  • detection of a temperature inversion in the broadband infrared Emission Spectrum of tres 4
    The Astrophysical Journal, 2009
    Co-Authors: Heather A Knutson, Adam Burrows, David Charbonneau, Francis T Odonovan, Georgi Mandushev
    Abstract:

    We estimate the strength of the bandpass-integrated thermal Emission from the extrasolar planet TrES-4 at 3.6, 4.5, 5.8, and 8.0 μ using the Infrared Array Camera on the Spitzer Space Telescope. We find relative eclipse depths of 0.137% ± 0.011%, 0.148% ± 0.016%, 0.261% ± 0.059%, and 0.318% ± 0.044% in these four bandpasses, respectively. We also place a 2σ upper limit of 0.37% on the depth of the secondary eclipse in the 16 μ IRS peak-up array. These eclipse depths reveal that TrES-4 has an Emission Spectrum similar to that of HD 209458b, which requires the presence of water Emission bands created by a thermal inversion layer high in the atmosphere in order to explain the observed features. TrES-4 receives more radiation from its star than HD 209458b and has a correspondingly higher effective temperature, therefore the presence of a temperature inversion in this planet's atmosphere lends support to the idea that inversions might be correlated with the irradiance received by the planet. We find no evidence for any offset in the timing of the secondary eclipse, and place a 3σ upper limit of |ecos(ω)| < 0.0058, where e is the planet's orbital eccentricity and ω is the argument of pericenter. From this we conclude that tidal heating from ongoing orbital circularization is unlikely to be the explanation for TrES-4's inflated radius.

  • detection of a temperature inversion in the broadband infrared Emission Spectrum of tres 4
    arXiv: Astrophysics, 2008
    Co-Authors: Heather A Knutson, Adam Burrows, David Charbonneau, Francis T Odonovan, Georgi Mandushev
    Abstract:

    We estimate the strength of the bandpass-integrated thermal Emission from the extrasolar planet TrES-4 at 3.6, 4.5, 5.8, and 8.0 micron using the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. We find relative eclipse depths of 0.137 +/- 0.011%, 0.148 +/- 0.016%, 0.261 +/- 0.059%, and 0.318 +/- 0.044% in these four bandpasses, respectively. We also place a 2 sigma upper limit of 0.37% on the depth of the secondary eclipse in the 16 micron IRS peak-up array. These eclipse depths reveal that TrES-4 has an Emission Spectrum similar to that of HD 209458b, which requires the presence of water Emission bands created by an thermal inversion layer high in the atmosphere in order to explain the observed features. TrES-4 receives more radiation from its star than HD 209458b and has a correspondingly higher effective temperature, therefore the presence of a temperature inversion in this planet's atmosphere lends support to the idea that inversions might be correlated with the irradiance received by the planet. We find no evidence for any offset in the timing of the secondary eclipse, and place a 3 sigma upper limit of |ecos(omega)|<0.0058 where e is the planet's orbital eccentricity and omega is the argument of pericenter. From this we conclude that tidal heating from ongoing orbital circulatization is unlikely to be the explanation for TrES-4's inflated radius.

  • the 3 6 8 0 μm broadband Emission Spectrum of hd 209458b evidence for an atmospheric temperature inversion
    The Astrophysical Journal, 2008
    Co-Authors: Heather A Knutson, Adam Burrows, David Charbonneau, Lori E Allen, Thomas S Megeath
    Abstract:

    We estimate the strength of the bandpass-integrated thermal Emission from the extrasolar planet HD 209458b at 3.6, 4.5, 5.8, and 8.0 μm using the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. We observe a single secondary eclipse simultaneously in all four bandpasses and find relative eclipse depths of 0.00094 ± 0.00009, 0.00213 ± 0.00015, 0.00301 ± 0.00043, and 0.00240 ± 0.00026, respectively. These eclipse depths reveal that the shape of the inferred Emission Spectrum for the planet differs significantly from the predictions of standard atmosphere models; instead, the most plausible explanation would require the presence of an inversion layer high in the atmosphere leading to significant water Emission in the 4.5 and 5.8 μm bandpasses. This is the first clear indication of such a temperature inversion in the atmosphere of a hot Jupiter, as previous observations of other planets appeared to be in reasonably good agreement with the predictions of models without such an inversion layer.