81 research outputs found

    HST and Spitzer Observations of the HD 207129 Debris Ring

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    A debris ring around the star HD 207129 (G0V; d = 16.0 pc) has been imaged in scattered visible light with the ACS coronagraph on the Hubble Space Telescope and in thermal emission using MIPS on the Spitzer Space Telescope at 70 microns (resolved) and 160 microns (unresolved). Spitzer IRS (7-35 microns) and MIPS (55-90 microns) spectrographs measured disk emission at >28 microns. In the HST image the disk appears as a ~30 AU wide ring with a mean radius of ~163 AU and is inclined by 60 degrees from pole-on. At 70 microns it appears partially resolved and is elongated in the same direction and with nearly the same size as seen with HST in scattered light. At 0.6 microns the ring shows no significant brightness asymmetry, implying little or no forward scattering by its constituent dust. With a mean surface brightness of V=23.7 mag per square arcsec, it is the faintest disk imaged to date in scattered light.Comment: 28 pages, 8 figure

    Forecasting the Impact of Stellar Activity on Transiting Exoplanet Spectra

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    Exoplanet host star activity, in the form of unocculted starspots or faculae, alters the observed transmission and emission spectra of the exoplanet. This effect can be exacerbated when combining data from different epochs if the stellar photosphere varies between observations due to activity. Here, we present a method to characterize and correct for relative changes due to stellar activity by exploiting multi-epoch (⩾2 visits/transits) observations to place them in a consistent reference frame. Using measurements from portions of the planet's orbit where negligible planet transmission or emission can be assumed, we determine changes to the stellar spectral amplitude. With the analytical methods described here, we predict the impact of stellar variability on transit observations. Supplementing these forecasts with Kepler-measured stellar variabilities for F-, G-, K-, and M-dwarfs, and predicted transit precisions by the James Webb Space Telescope's (JWST) NIRISS, NIRCam, and MIRI, we conclude that stellar activity does not impact infrared transiting exoplanet observations of most presently known or predicted TESS targets by current or near-future platforms, such as JWST, as activity-induced spectral changes are below the measurement precision

    The Vehicle, Fall 1983

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    Vol. 25, No. 1 Table of Contents Amish BoyDevon Flesorpage 3 SyllogismJ. Maura Davispage 3 Ten SecondsD.L. Lewispage 4 The Cedar ChestBridget M. Howepage 4 A Christmas With CarolSteve Longpage 5 TeethMichelle Mitchellpage 7 An I-Love-You PoemD.L. Lewispage 8 The Dragon SlayerSusan Gradypage 8 A DefinitionAmy J. Eadespage 9 FingernailsSuzanne Hornpage 10 The Liar\u27s TableBrook Wilsonpage 10 Fifi\u27s Last PartySteve Longpage 12 Absence/PresenceSuzanne Hornpage 13 From the Rantings of a Mad Astronomy StudentAmy J. Eadespage 13 In the Name of the Father, the Son, and MachiavelliF. Link Rapierpage 15 Errant LoverBecky Lawsonpage 16 DaddyKevin Lylespage 16 GhostsGary Ervinpage 17 TangoF. Link Rapierpage 17 Grandma\u27s SlippersBecky Lawsonpage 18 EdgesAmy J. Eadespage 19 Having ChildrenDevon Flesorpage 20 Young Black GirlKevin Lylespage 21 CatSuzanne Hornpage 22 Breakfast for OneMichelle Mitchellpage 22 A Modest ProposalBrooke Sanfordpage 23 Post MortemF. Link Rapierpage 26 Who Said I Forgot?Lynne Krausepage 27 The Corner Booth at StuckeysMaggie Kennedypage 28 The First DayDavis Brydenpage 29 DownLynne Krausepage 30 Fairie RingDevon Flesorpage 31 The LaundrymatKathy Fordpage 32 Sunday in OctoberBridget M. Howepage 32 The Kitchen WindowMaggie Kennedypage 33 UntitledChristina Maire Vitekpage 34 8th Grade Field Trip to SpringfieldMichelle Mitchellpage 34 Children of the FortiesF. Link Rapierpage 35 one winter and i was eightGary Ervinpage 35 Don\u27t we all know?Thomas B. Waltrippage 36 The TravelerMaggie Kennedypage 36 The VisitKathy Fordpage 40 CubismMaggie Kennedypage 40https://thekeep.eiu.edu/vehicle/1042/thumbnail.jp

    The Vehicle, Fall 1983

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    Vol. 25, No. 1 Table of Contents Amish BoyDevon Flesorpage 3 SyllogismJ. Maura Davispage 3 Ten SecondsD.L. Lewispage 4 The Cedar ChestBridget M. Howepage 4 A Christmas With CarolSteve Longpage 5 TeethMichelle Mitchellpage 7 An I-Love-You PoemD.L. Lewispage 8 The Dragon SlayerSusan Gradypage 8 A DefinitionAmy J. Eadespage 9 FingernailsSuzanne Hornpage 10 The Liar\u27s TableBrook Wilsonpage 10 Fifi\u27s Last PartySteve Longpage 12 Absence/PresenceSuzanne Hornpage 13 From the Rantings of a Mad Astronomy StudentAmy J. Eadespage 13 In the Name of the Father, the Son, and MachiavelliF. Link Rapierpage 15 Errant LoverBecky Lawsonpage 16 DaddyKevin Lylespage 16 GhostsGary Ervinpage 17 TangoF. Link Rapierpage 17 Grandma\u27s SlippersBecky Lawsonpage 18 EdgesAmy J. Eadespage 19 Having ChildrenDevon Flesorpage 20 Young Black GirlKevin Lylespage 21 CatSuzanne Hornpage 22 Breakfast for OneMichelle Mitchellpage 22 A Modest ProposalBrooke Sanfordpage 23 Post MortemF. Link Rapierpage 26 Who Said I Forgot?Lynne Krausepage 27 The Corner Booth at StuckeysMaggie Kennedypage 28 The First DayDavis Brydenpage 29 DownLynne Krausepage 30 Fairie RingDevon Flesorpage 31 The LaundrymatKathy Fordpage 32 Sunday in OctoberBridget M. Howepage 32 The Kitchen WindowMaggie Kennedypage 33 UntitledChristina Maire Vitekpage 34 8th Grade Field Trip to SpringfieldMichelle Mitchellpage 34 Children of the FortiesF. Link Rapierpage 35 one winter and i was eightGary Ervinpage 35 Don\u27t we all know?Thomas B. Waltrippage 36 The TravelerMaggie Kennedypage 36 The VisitKathy Fordpage 40 CubismMaggie Kennedypage 40https://thekeep.eiu.edu/vehicle/1042/thumbnail.jp

    Constraining Exoplanet Metallicities and Aerosols with ARIEL: An Independent Study by the Contribution to ARIEL Spectroscopy of Exoplanets (CASE) Team

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    Launching in 2028, ESA's Atmospheric Remote-sensing Exoplanet Large-survey (ARIEL) survey of \sim1000 transiting exoplanets will build on the legacies of Kepler and TESS and complement JWST by placing its high precision exoplanet observations into a large, statistically-significant planetary population context. With continuous 0.5--7.8~μ\mum coverage from both FGS (0.50--0.55, 0.8--1.0, and 1.0--1.2~μ\mum photometry; 1.25--1.95~μ\mum spectroscopy) and AIRS (1.95--7.80~μ\mum spectroscopy), ARIEL will determine atmospheric compositions and probe planetary formation histories during its 3.5-year mission. NASA's proposed Contribution to ARIEL Spectroscopy of Exoplanets (CASE) would be a subsystem of ARIEL's FGS instrument consisting of two visible-to-infrared detectors, associated readout electronics, and thermal control hardware. FGS, to be built by the Polish Academy of Sciences' Space Research Centre, will provide both fine guiding and visible to near-infrared photometry and spectroscopy, providing powerful diagnostics of atmospheric aerosol contribution and planetary albedo, which play a crucial role in establishing planetary energy balance. The CASE team presents here an independent study of the capabilities of ARIEL to measure exoplanetary metallicities, which probe the conditions of planet formation, and FGS to measure scattering spectral slopes, which indicate if an exoplanet has atmospheric aerosols (clouds and hazes), and geometric albedos, which help establish planetary climate. Our design reference mission simulations show that ARIEL could measure the mass-metallicity relationship of its 1000-planet single-visit sample to >7.5σ>7.5\sigma and that FGS could distinguish between clear, cloudy, and hazy skies and constrain an exoplanet's atmospheric aerosol composition to >5σ>5\sigma for hundreds of targets, providing statistically-transformative science for exoplanet atmospheres.Comment: accepted to PASP; 23 pages, 6 figure

    Sorl1 as an Alzheimer's disease predisposition gene?

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    Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressively disabling impairments in memory, cognition, and non-cognitive behavioural symptoms. Sporadic AD is multifactorial and genetically complex. While several monogenic mutations cause early-onset AD and gene alleles have been suggested as AD susceptibility factors, the only extensively validated susceptibility gene for late-onset AD is the apolipoprotein E (APOE) epsilon4 allele. Alleles of the APOE gene do not account for all of the genetic load calculated to be responsible for AD predisposition. Recently, polymorphisms across the neuronal sortilin-related receptor (SORL1) gene were shown to be significantly associated with AD in several cohorts. Here we present the results of our large case-control whole-genome scan at over 500,000 polymorphisms which presents weak evidence for association and potentially narrows the association interval

    The Vehicle, Fall 1984

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    Vol. 26, No. 1 Table of Contents Thoughts on I-57Jim Caldwellpage 3 A Night Between Lonely and BlindJennifer K. Soulepage 4 What is Unnatural is Sometimes MagicAngelique Jenningspage 4 Cutting ClosenessBecky Lawsonpage 5 PhotoBrian Ormistonpage 6 The Sensuality of Corn One Week in AugustMichelle Mitchellpage 7 American MusicJim Caldwellpage 7 Water is WaitingMichael Kuopage 8 WhereJennifer K. Soulepage 8 The Fishing HoleJan Kowalskipage 9 Miller\u27s PondSue Gradypage 9 PhotoCathy Stonerpage 11 Young Man Reading To His LoverMaggie Kennedypage 11 ShellsChristopher R. Albinpage 12 In The ShadeJohn Fehrmannpage 12 FallLynanne Feilenpage 13 IndecisionDave L. Brydenpage 13 Dark Falls SoftlyAngelique Jenningspage 14 Not a Parked \u2757 Chevy in the Summer in the CountryMichelle Mitchellpage 20 BirdAnnie Heisepage 20 Clouds Created Only For Poets And Certain WomenJennifer K. Soulepage 21 SandGraham Lewispage 22 PhotoFred Zwickypage 23 Judgment CallCathy Moepage 23 I was hip that night Dan Hintzpage 24 A Sight Of WindDan Von Holtenpage 25 Tillard Isabel M. Parrottpage 26 The WidowMaggie Kennedypage 27 The SeparationMichelle Mitchellpage 27 The Garden Hose TrialMaggie Kennedypage 28 InterruptionsJennifer K. Soulepage 28 On Happening Across Jesus While Cleaning the BasementMaggie Kennedypage 29 GileonMichelle Mitchellpage 30 If My Father Were A Writer, He Would Still BuildAngelique Jenningspage 36 A Visit to Grandpa Gib\u27s HouseTammy Veachpage 37 For Having SeenAngelique Jenningspage 38 PhotoJudy Klancicpage 39 The Earth in BlueSusan J. Bielskypage 39 Things I Could Have SaidAngelique Jenningspage 40 AcrosticsAnnie Heisepage 40https://thekeep.eiu.edu/vehicle/1044/thumbnail.jp

    The Vehicle, Fall 1984

    Get PDF
    Vol. 26, No. 1 Table of Contents Thoughts on I-57Jim Caldwellpage 3 A Night Between Lonely and BlindJennifer K. Soulepage 4 What is Unnatural is Sometimes MagicAngelique Jenningspage 4 Cutting ClosenessBecky Lawsonpage 5 PhotoBrian Ormistonpage 6 The Sensuality of Corn One Week in AugustMichelle Mitchellpage 7 American MusicJim Caldwellpage 7 Water is WaitingMichael Kuopage 8 WhereJennifer K. Soulepage 8 The Fishing HoleJan Kowalskipage 9 Miller\u27s PondSue Gradypage 9 PhotoCathy Stonerpage 11 Young Man Reading To His LoverMaggie Kennedypage 11 ShellsChristopher R. Albinpage 12 In The ShadeJohn Fehrmannpage 12 FallLynanne Feilenpage 13 IndecisionDave L. Brydenpage 13 Dark Falls SoftlyAngelique Jenningspage 14 Not a Parked \u2757 Chevy in the Summer in the CountryMichelle Mitchellpage 20 BirdAnnie Heisepage 20 Clouds Created Only For Poets And Certain WomenJennifer K. Soulepage 21 SandGraham Lewispage 22 PhotoFred Zwickypage 23 Judgment CallCathy Moepage 23 I was hip that night Dan Hintzpage 24 A Sight Of WindDan Von Holtenpage 25 Tillard Isabel M. Parrottpage 26 The WidowMaggie Kennedypage 27 The SeparationMichelle Mitchellpage 27 The Garden Hose TrialMaggie Kennedypage 28 InterruptionsJennifer K. Soulepage 28 On Happening Across Jesus While Cleaning the BasementMaggie Kennedypage 29 GileonMichelle Mitchellpage 30 If My Father Were A Writer, He Would Still BuildAngelique Jenningspage 36 A Visit to Grandpa Gib\u27s HouseTammy Veachpage 37 For Having SeenAngelique Jenningspage 38 PhotoJudy Klancicpage 39 The Earth in BlueSusan J. Bielskypage 39 Things I Could Have SaidAngelique Jenningspage 40 AcrosticsAnnie Heisepage 40https://thekeep.eiu.edu/vehicle/1044/thumbnail.jp
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