Printed by SSC Jan 29, 20 19:21 Spitzer Approved Warm Mission Abstracts Page 1/750 Jan 29, 20 19:21 Spitzer Approved Warm Mission Abstracts Page 2/750 Spitzer Space Telescope − Directors Discretionary Time Proposal #13159 Spitzer Space Telescope − General Observer Proposal #60167 Variability at the edge: highly accreting objects in Taurus Disk tomography and dynamics: a time−dependent study of known mid−infrared Principal Investigator: Peter Abraham variable young stellar objects Institution: Konkoly Observatory Principal Investigator: Peter Abraham Technical Contact: Peter Abraham, Konkoly Observatory Institution: Konkoly Observatory of the Hungarian Academy of Science Co−Investigators: Technical Contact: Peter Abraham, Konkoly Observatory of the Hungarian Agnes Kospal, Konkoly Observatory Academy of Science Robert Szabo, Konkoly Observatory Co−Investigators: Science Category: YSOs Jose Acosta−Pulido, Instituto de Astrofisica de Canarias Observing Modes: IRAC Post−Cryo Mapping Cornelis P. Dullemond, Max−Planck−Institut fur Astronomie Hours Approved: 9.3 Carol A. Grady, Eureka Sci/NASA Goddard Thomas Henning, Max−Planck−Institut fur Astronomie Abstract: Attila Juhasz, Max−Planck−Institut fur Astronomie In Kepler K2, Campaign 13, we will obtain 80−days−long optical light curves of Csaba Kiss, Konkoly Observatory seven highly accreting T Tauri stars in the benchmark Taurus star forming Agnes Kospal, Leiden Observatory region. Here we propose to monitor our sample simultaneously with Kepler and Maria Kun, Konkoly Observatory Spitzer, to be able to separate variability patterns related to different David Westley Miller, University of Louisville physical processes. Monitoring our targets with Spitzer during the final 11 Attila Moor, Konkoly Observatory days of the K2 campaign, we will clean the light curves from non−accretion Aurora Sicilia−Aguilar, Max−Planck−Institut fur Astronomie effects (rotating stellar spots, dips due to passing dust structures), and construct, for the first time, a variability curve which reflects the Science Category: young stellar objects time−dependent accretion only. We will then study and understand how Observing Modes: IRAC Post−Cryo Mapping time−dependent mass accretion affects the density and temperature structure of Hours Approved: 49.3 the protoplanetary disk, which sets the initial conditions for planet formation. The proposed work cannot be done without the unparalleled precision Abstract: of Kepler and Spitzer. This unique and one−time opportunity motivated our DDT Most of our knowledge on young stars comes from snapshot observations: spectra proposal. and images taken at a single epoch, or at different epochs at different wavelengths. It is, however, known that many of the systems are variable. Variability at optical and near−infrared wavelength is mostly related to the central star itself. Mid−infrared flux changes, on the other hand, are in most cases due to varying emission of the circumstellar material, either via varying accretion rate (and thus changing thermal emission), or varying extinction along the line−of−sight (shadowing effects). If the illuminated disk area varies with time, measuring the variable integrated flux offers a tomographic analysis. Monitoring and interpreting variability provide a powerful "extra dimension" of information on the structure of the circumstellar material. The Spitzer Warm Mission is a unique opportunity for the systematic establishment of mid−infrared variability studies of young stars. Following an extensive preparatory work, we compiled a list of young stellar objects with variable mid−infrared brightness. We propose to conduct a multi−epoch survey of these carefully selected pre−main sequence stars with Spitzer. We plan to complement the Spitzer observations with simultaneous optical and near−infrared photometry from ground−based telescopes. Our aim is to document the mid−infrared brightness evolution of our targets, examine the possible reasons of the observed variability, model disk structure and dynamics for different scenarios and confront the data with model predictions. Wednesday January 29, 2020 Spitzer_abstracts_warm.txt 1/375 Printed by SSC Jan 29, 20 19:21 Spitzer Approved Warm Mission Abstracts Page 3/750 Jan 29, 20 19:21 Spitzer Approved Warm Mission Abstracts Page 4/750 Spitzer Space Telescope − General Observer Proposal #80165 Spitzer Space Telescope − Directors Discretionary Time Proposal #14223 Revisiting and refining the model of TRAPPIST−1 with Spitzer Disk tomography during the outburst of two new young eruptive stars Principal Investigator: Eric Agol Principal Investigator: Peter Abraham Institution: University of Washington Institution: Konkoly Observatory Technical Contact: Eric Agol, University of Washington Technical Contact: Peter Abraham, Konkoly Observatory Co−Investigators: Co−Investigators: Emeline Bolmont, University of Geneva Agnes Kospal, Leiden Observatory Adam Burgasser, UCSD Attila Moor, Konkoly Observatory Sean Carey, IPAC Laetitia Delrez, University of Cambridge Science Category: young stellar objects Brice−Olivier Demory, University of Bern Observing Modes: IRAC Post−Cryo Mapping Dan Fabrycky, University of Chicago Hours Approved: 1.8 Michael Gillon, University of Liege Simon Grimm, University of Bern Abstract: Jim Ingalls, IPAC Most young stars are variable, and not only at optical, but also at infrared Renu Malhotra, University of Arizona wavelengths. Our group had proposed a new method to interpret such light Brett Morris, University of Washington variations using a tomographic technique. It is based on analyzing the time Sean Raymond, University of Bordeaux variations of the integrated flux of a shrinking illuminated disk area during Amaury Triaud, University of Birmingham the fading. We also suggested that rearrangement in the density structure of the inner disk − mainly due to evaporation/condensation of dust particles in the Science Category: Exoplanets outburst heat − can be seen in the multicolor light curves. The outbursts of two Observing Modes: IRAC Post−Cryo Mapping so−far unknown young eruptive stars in Cygnus in 2010 August offer the Hours Approved: 103.0 long−waited opportunity to perform a proof−of−concept analysis of our proposed Priority: 1 methods to investigate disk tomography and dynamics. Here we propose to conduct a multi−epoch survey of two young eruptive star during their outburst with Spitzer/IRAC. We will obtain 3.6 and 4.5 um images at 9 epochs, and the data Abstract: will be supplemented by simultaneous ground−based optical and near−infrared With the Spitzer Space Telescope, we have discovered a system of seven photometry. The flux and color variations of HBC 722 will be interpreted using transiting planets about the star TRAPPIST−1, and for the first time measured the new method of disk tomography, while the corresponding data on VSX the densities of three Earth−sized, temperate exoplanets using transit−timing J205126.1+440523 will be interpreted in terms of the sum of variable variations (Gillon et al. 2017; Ducrot et al. 2018; Grimm et al. 2018). We illumination and time variable density structure of the inner disk/envelope. propose to gather additional transits of the TRAPPIST−1 system, focusing on the Our study may demonstrate that variability, in particular the wavelength outer planets in the system which have had fewer transits observed to date. The dependence of flux variations over the whole infrared domain, provides an four−fold goals of this proposal are: i). to flag potential transits which extremely powerful ?extra dimension? of information, in addition to space and might be affected by stellar variability; ii). to constrain the dynamical state wavelength. of the planet system; iii). to better constrain the masses of the planets; iv). to tighten the ephemeris forecast for observations with JWST. In addition, we will search for any evidence an eighth planet, characterize the stellar variability, and forecast planet−planet overlaps during transits. The proposed observations contain measurements which are only possible in March−April 2019, and so we request a time critical review to the extent possible. Wednesday January 29, 2020 Spitzer_abstracts_warm.txt 2/375 Printed by SSC Jan 29, 20 19:21 Spitzer Approved Warm Mission Abstracts Page 5/750 Jan 29, 20 19:21 Spitzer Approved Warm Mission Abstracts Page 6/750 Spitzer Space Telescope − General Observer Proposal #70157 Spitzer Space Telescope − General Observer Proposal #12112 Star formation in the 4th Galactic Quadrant Variability of Two Young L/T Transition Brown Dwarfs Principal Investigator: Lori Allen Principal Investigator: Katelyn Allers Institution: Smithsonian Astrophysical Observatory Institution: Institute for Astronomy Technical Contact: Lori Allen, Smithsonian Astrophysical Observatory Technical Contact: Katelyn Allers, Institute for Astronomy Co−Investigators: Co−Investigators: Sarah Willis, Iowa State University Beth Biller, University of Edinburgh Massimo Marengo, Iowa State University Jack Gallimore, Bucknell University Tom Megeath, University of Toledo Ian Crossfield, Lunar and Planetary Lab, University of Arizona Rob Gutermuth, University of Massachusetts / Smith College Science Category: brown dwarfs/very low mass stars Science Category: star formation Observing Modes: IRAC Post−Cryo Mapping Observing Modes: IRAC Post−Cryo Mapping Hours Approved: 29.7 Hours Approved: 35.5 Priority: 2 Abstract: Abstract: Empirical scaling laws relating star formation rates to gas surface density in We propose for