15497( 5) - 14-Dec-2018 21:53:42 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 15497 Version: 5 Check-in Time: 14-Dec-2018 21:53:42 STScI Edit Number: 1 Title Resolving the late planet formation stages around young M-stars ------------------------------------------------------------------------------------ Type Cycle GO 26 ------------------------------------------------------------------------------------ Investigators Contact? PI: Maxwell Andrew Millar-Blanchaer Jet Propulsion Laboratory Y CoI: Dr. Paul George Kalas University of California - Berkeley N CoI: Dr. Marshall Perrin Space Telescope Science Institute N CoI: Dr. James R. Graham University of California - Berkeley N CoI: Dr. Karl Stapelfeldt Jet Propulsion Laboratory N CoI: Dr. Anneila I. Sargent California Institute of Technology N CoI: Dr. John Carpenter Associated Universities, Inc. N CoI: Scott Barenfeld California Institute of Technology N ------------------------------------------------------------------------------------ Abstract Recent discoveries of earth-like planets around M-stars have highlighted the importance of understanding planet formation around late-type stars. However, this effort has been hampered by the lack of resolved observations of protoplanetary disks. In particular, scattered light images of M-star disks near the age of dispersal are critical to making further progress. The Upper Sco region provides a promising venue to remedy this situation, as it is the closest region with an age of 5-11 Myrs, commensurate with dispersal timescales. We propose to observe three M-star protoplanetary disks in the Upper Sco association using HST/STIS coronography to resolve the disks in scattered-light for the first time and to search for morphological signatures of forming planets. These three disks have been selected based on ALMA mm-dust and CO measurements that display radii within the STIS field of view and outside its inner working angle (IWA). We will use these observations to carry out a comparative study of the evolutionary state between M-star disks in Upper Sco and the younger 1-2 Myr Taurus region, leveraging both previous scattered-light images of disks in Taurus, as well as previous observations of the mm-dust and CO in both regions. All three targets are too faint to be observed using ground-based AO. Therefore, HST/STIS is the only instrument able to make these important measurements. These observations will act as critical diagnostics of the evolutionary state of nearby M-star protoplanetary disks, that will inform theories of planet formation and will further our understanding of the evolution of the planets around M-stars, such as our nearest neighbor Proxima Centauri b. ------------------------------------------------------------------------------------ Observations Description ------------------------ Our observations seek to take advantage of the recently commissioned STIS BAR5 (i.e. the bent finger; Gaspar & Schneider, GO-12923) coronagraphic mode to achieve the 0.25" inner working angle required to image these three disks in scattered light. The expected outer radius of the scattered-light disk is unknown, as the exact relationship between the small dust and the CO at these evolved stages is unknown, but it is expected to be at least that of the CO radius (and therefore observable with STIS), but possibly extending further. 15497( 5) - 14-Dec-2018 21:53:42 - [ 2] Empirically measuring the relationship between these two components is one of the main goals of this proposal. The relatively small angular separations of the expected emission in these disks (~0.5") necessitates the use of PSF subtraction techniques in order to reasonably expect a detection. We therefore use three orbits per target: two orbits at different telescope ORIENT positions separated from each other by 30 degrees, and one orbit for a reference star. The first two roll-orbits allow for basic angular differential imaging PSF subtraction while building signal to noise in a given disk, and the third orbit is required to mitigate self-subtraction of the disk in order to recover its true morphology. This multi-roll-plus-reference-star PSF subtraction strategy is well established and has led to many successfully imaged disks (e.g. Schneider et al., 2014). In each case the ORIENTs are assigned using the disk's known position angle such that the disk does not fall behind either a diffraction spike or the BAR5 finger itself. The three reference stars for this program are RAVE-J161322.1-192417, UCAC2- 24134747 and 2MASS-J16150856-1851009 - one for each target. Each reference star was chosen to match the B-V color, the Vmag and the position in the sky as close as possible. ------------------------------------------------------------------------------------ 15497( 5) - 14-Dec-2018 21:53:42 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 3 T64-6 STAR, DISK RA=16H12M39.1690S, J2000 V = 14.3 +/- 0.3 DEC=-18D59'28.51" Reference Frame: ICRS Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. Position angle of disk around 2MASS J16123916-1859284 (T64-6) PA = 105 (+11 -11) ------------------------------------------------------------------------------------------------------------------------------------ 6 2MASS-J16150 STAR, M V-IV RA=16H15M8.5600S, J2000 V = 14.5 +/- 0.2 856-1851009 DEC=-18D51'1.00" Reference Frame: ICRS Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. ------------------------------------------------------------------------------------------------------------------------------------ 15497( 5) - 14-Dec-2018 21:53:42 - [ 4] Visit: 07 Visit Requirements: ORIENT 119D TO 119.5 D; SEQ 07, 09, 10 WITHIN 2.9 Orbits On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 T64-6 STIS/CCD ACQ 50CCD MIRROR 1 1 S (1 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 T64-6 STIS/CCD ACCUM BAR10 MIRROR CR-SPLIT=6, GAIN=4 1 2214 S POS TARG 16.34596, (2214 S) -7.17672 ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ T64-6 1 STIS/CCD ACQ 50CCD MIRROR none none none none 1 N/A T64-6 2 STIS/CCD ACCUM BAR10 MIRROR none none none 1 1 N/A T64-6 2 STIS/CCD ACCUM BAR10 MIRROR none none none 2 1 N/A T64-6 2 STIS/CCD ACCUM BAR10 MIRROR none none none 3 1 N/A T64-6 2 STIS/CCD ACCUM BAR10 MIRROR none none none 4 1 N/A T64-6 2 STIS/CCD ACCUM BAR10 MIRROR none none none 5 1 N/A T64-6 2 STIS/CCD ACCUM BAR10 MIRROR none none none 6 1 N/A 15497( 5) - 14-Dec-2018 21:53:42 - [ 5] Visit: 09 Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 2MASS-J1615 STIS/CCD ACQ 50CCD MIRROR 1 1 S (1 S) 0856-185100 9 ------------------------------------------------------------------------------------------------------------------------------------ 2 2MASS-J1615 STIS/CCD ACCUM BAR10 MIRROR CR-SPLIT=6, GAIN=4 1 2214 S POS TARG 16.34596, 0856-185100 (2214 S) -7.17672 9 ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ 2MASS-J16150856-185 1 STIS/CCD ACQ 50CCD MIRROR none none none none 1 N/A 1009 2MASS-J16150856-185 2 STIS/CCD ACCUM BAR10 MIRROR none none none 1 1 N/A 1009 2MASS-J16150856-185 2 STIS/CCD ACCUM BAR10 MIRROR none none none 2 1 N/A 1009 2MASS-J16150856-185 2 STIS/CCD ACCUM BAR10 MIRROR none none none 3 1 N/A 1009 2MASS-J16150856-185 2 STIS/CCD ACCUM BAR10 MIRROR none none none 4 1 N/A 1009 2MASS-J16150856-185 2 STIS/CCD ACCUM BAR10 MIRROR none none none 5 1 N/A 1009 2MASS-J16150856-185 2 STIS/CCD ACCUM BAR10 MIRROR none none none 6 1 N/A 1009 15497( 5) - 14-Dec-2018 21:53:42 - [ 6] Visit: 10 Visit Requirements: ORIENT 16D TO 21D FROM 07 On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 T64-6 STIS/CCD ACQ 50CCD MIRROR 1 1 S (1 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 T64-6 STIS/CCD ACCUM BAR10 MIRROR CR-SPLIT=6, GAIN=4 1 2214 S POS TARG 16.34596, (2214 S) -7.17672 ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ T64-6 1 STIS/CCD ACQ 50CCD MIRROR none none none none 1 N/A T64-6 2 STIS/CCD ACCUM BAR10 MIRROR none none none 1 1 N/A T64-6 2 STIS/CCD ACCUM BAR10 MIRROR none none none 2 1 N/A T64-6 2 STIS/CCD ACCUM BAR10 MIRROR none none none 3 1 N/A T64-6 2 STIS/CCD ACCUM BAR10 MIRROR none none none 4 1 N/A T64-6 2 STIS/CCD ACCUM BAR10 MIRROR none none none 5 1 N/A T64-6 2 STIS/CCD ACCUM BAR10 MIRROR none none none 6 1 N/A 15497( 5) - 14-Dec-2018 21:53:42 - [ 7] Summary Form for Proposal 15497 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures 50CCD, BAR10 ------------------------------------------------------------------------------------------------------------------------------------ Configurations STIS/CCD ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, ACQ ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=6, GAIN=4 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 119D TO 119.5 D, ORIENT 16D TO 21D FROM 07, POS TARG 16.34596, -7.17672, SEQ 07, 09, 10 WITHIN 2.9 Orbits ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR ------------------------------------------------------------------------------------------------------------------------------------ Target Names 2MASS-J16150856-1851009, T64-6 ------------------------------------------------------------------------------------------------------------------------------------