14330( 6) - 11-Jul-2018 18:23:56 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 14330 Version: 6 Check-in Time: 11-Jul-2018 18:23:56 STScI Edit Number: 3 Title Astrometric search for Planets in the closest Brown Dwarf Binary system Luhman 16AB ------------------------------------------------------------------------------------ Type Cycle GO 23 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Luigi R. Bedin Osservatorio Astronomico di Padova Y CoI: Dr. Esther Buenzli Eidgenossiche Technische Hochschule (ETH) N CoI: Dr. Henri M.J. Boffin European Southern Observatory - Chile N CoI: Dr. Valerio Nascimbeni Universita degli Studi di Padova N CoI: Prof. Daniel Apai University of Arizona N CoI: Prof. Adam J. Burgasser University of California - San Diego N ------------------------------------------------------------------------------------ Abstract Located at 2.0 pc, the L8+T1 dwarfs system Luhman16AB is the third closest system known to Earth, making it a key benchmark for detailed investigation of brown dwarf atmospheric properties, thermal evolution, multiplicity and planet-hosting frequency. Indeed, a recent ground-based astrometric campaign suggested this system to host a 5-30 Jupiter masses exoplanet. We propose to use HST in spatial-scanning mode to obtain the most accurate annual parallax of any brown dwarf to date, achieving an unprecedented accuracy of 1 part in 10000 (50 micro-arcsecond) for each of the two components of Luh16, and to constrain their absolute space motions with similar accuracy. Most importantly, we will be able to confirm the giant planet candidate and to search for faint companions co-moving with the targets, either resolved or through astrometric perturbations of the A-B orbital motion, the latter probing down to few Earth-masses. Present-day ground-based direct imaging and AO facilities have fundamental limitations (field of view, PSF stability, differential chromatic effects, visibility) which introduce systematic and seasonal errors that are hard to quantify, and which have already resulted many times in clamorous false alarm in the recent past. This is particularly true for faint and red objects. Luhman 16A and B will be problematic for GAIA (faint, color, crowding, visibility), and the here proposed HST spatial-scanning mode observations will actually be an important complementary validation of the final GAIA catalog itself (expected 2020). Similarly, JWST is not expected to provide any better astrometry than HST because of its broader and irregular PSFs. ------------------------------------------------------------------------------------ Observations Description ------------------------ Each visit is scheduled in a 4-10 days window, centered at a well defined epoch. These epochs are choose as to better constraints the maxima elongation along the major and minor axis 14330( 6) - 11-Jul-2018 18:23:56 - [ 2] of the annual parallax of Luh16AB, its proper motions, the cusp and curve of the resulting cycloid combined motions, and to sample presence of possible extrasolar planets with periods between ~15 days and ~6months. Three epochs are taken at the maxima elongation along the annual parallax semi-major axis. Five epochs at the maxima elongations along the semi-minor axis of the annual parallax. Three epochs are taken at the cycloid (pms+annaual annual parallax) curles of the Luh16AB proper motions (visits labeled "ricciolo"), and two epochs at the bottom of the cycloid motion (visits labeled "pancia"). For total of 3+5+3+2 = 13 epochs. Eleven of these epochs should be taken within Cycle 22, and the last two within Cycle 23. The first epoch should be taken as early as possible (this should be in this August 29th, 2014). Each epoch contains three images in point source imaging mode, and four in spatial-scanning mode with WFC3/UVIS. In addition to the images taken in spatial scan mode and to the short two point-source images at the beginning and at the end of the single orbit-visits --- as requested at the phase I stage --- it turned out possible to fit in the orbit one extra point source images of 348s in F606W. The color information will be a precious to discriminate the nature (and so the distance) of the reference sources in the field (for example to separate slow close by red dwarf from far away giants). ------------------------------------------------------------------------------------ 14330( 6) - 11-Jul-2018 18:23:56 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 7 LUHMAN16AB-R STAR, BROWN DWARF RA=10H49M15.0000S, J2000 V = 24 +/- 1 Sloan-i = 15 +/- .5 ICCIOLO-1 DEC=-53D19'12.00" Reference Frame: ICRS Comments: We have mapped the relative path of Luhman 16AB between 2014 and 2016 ------------------------------------------------------------------------------------------------------------------------------------ 5 LUHMAN16ABMI STAR, BROWN DWARF RA=10H49M16.5000S, J2000 V = 24 +/- 1 Sloan-i = 15 +/- .5 NAPNE1 DEC=-53D19'40.00" Reference Frame: ICRS Comments: We have mapped the relative path of Luhman 16AB between 2014 and 2016 ------------------------------------------------------------------------------------------------------------------------------------ 14330( 6) - 11-Jul-2018 18:23:56 - [ 4] Visit: 06 (2016-10-05 mAP_NE_3) Visit Requirements: ORIENT 220D TO 220 D; BETWEEN 01-OCT-2016 AND 11-OCT-2016 On Hold Comments: Additional Comments: Epoch 2016-10-05. This is the epoch is taken at the minimum NE-elongation in the minor axis of the annual parallax (AP). The epococh must be around 2016-10-05 +/- 25 days Then we want to scan perpendicularly to the minor axis. ORIENTATION = ~ 90d or ~270d +/- 35d main SCAN along Y, where CTE are worse, so SCAN ORIENT. secondary SCAN along X. A suitalbe window seems to be between 28 September 2015 and 15 Oct 2016. The closer to the Oct 5th 2016, the better. 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 LUHMAN16ABM WFC3/UVI ACCUM UVIS1 F814W FLASH=12 1 60 S (60 POS TARG -4, 4 INAPNE1 S S) ------------------------------------------------------------------------------------------------------------------------------------ 2 LUHMAN16ABM WFC3/UVI ACCUM UVIS1 F814W FLASH=12 1 348 S (348 POS TARG -4, 4; SPATIAL INAPNE1 S S) SCAN 0.012, 270.0 Degrees, Forward ------------------------------------------------------------------------------------------------------------------------------------ 3 LUHMAN16ABM WFC3/UVI ACCUM UVIS1 F814W FLASH=12 1 348 S (348 POS TARG -4, -4; SPATIAL INAPNE1 S S) SCAN 0.012, 0.0 Degrees, Forward ------------------------------------------------------------------------------------------------------------------------------------ 4 LUHMAN16ABM WFC3/UVI ACCUM UVIS1 F606W FLASH=12 1 348 S (348 POS TARG 0, 0 INAPNE1 S S) ------------------------------------------------------------------------------------------------------------------------------------ 5 LUHMAN16ABM WFC3/UVI ACCUM UVIS1 F814W FLASH=12 1 348 S (348 POS TARG 4, 4; SPATIAL INAPNE1 S S) SCAN 0.012, 180.0 Degrees, Forward ------------------------------------------------------------------------------------------------------------------------------------ 6 LUHMAN16ABM WFC3/UVI ACCUM UVIS1 F814W FLASH=12 1 348 S (348 POS TARG 4, -4; SPATIAL INAPNE1 S S) SCAN 0.012, 90.0 Degrees, Forward ------------------------------------------------------------------------------------------------------------------------------------ 7 LUHMAN16ABM WFC3/UVI ACCUM UVIS1 F814W FLASH=12 1 60 S (60 POS TARG 4, -4 INAPNE1 S S) ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ 14330( 6) - 11-Jul-2018 18:23:56 - [ 5] 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 | ------------------------------------------------------------------------------------------------------------------------------------ LUHMAN16ABMINAPNE1 1 WFC3/UVI ACCUM UVIS1 F814W none none none none 1 N/A S LUHMAN16ABMINAPNE1 2 WFC3/UVI ACCUM UVIS1 F814W none none none none 1 N/A S LUHMAN16ABMINAPNE1 3 WFC3/UVI ACCUM UVIS1 F814W none none none none 1 N/A S LUHMAN16ABMINAPNE1 4 WFC3/UVI ACCUM UVIS1 F606W none none none none 1 N/A S LUHMAN16ABMINAPNE1 5 WFC3/UVI ACCUM UVIS1 F814W none none none none 1 N/A S LUHMAN16ABMINAPNE1 6 WFC3/UVI ACCUM UVIS1 F814W none none none none 1 N/A S LUHMAN16ABMINAPNE1 7 WFC3/UVI ACCUM UVIS1 F814W none none none none 1 N/A S 14330( 6) - 11-Jul-2018 18:23:56 - [ 6] Visit: 11 (2016-08-29 Ricciolo_3) Visit Requirements: ORIENT 160D TO 165 D; BETWEEN 20-AUG-2018 AND 23-AUG-2018 On Hold Comments: Additional Comments: Epoch 2016-08-29. This is the epoch is taken at the ricciolo of the cycloid apparent motion. The epoch must be around 2016-08-29 +/- 15 days main SCAN along Y, where CTE are worse, so SCAN ORIENT. secondary SCAN along X. 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 LUHMAN16AB- WFC3/UVI ACCUM UVIS1 F814W FLASH=12 1 60 S (60 POS TARG -4, 4 RICCIOLO-1 S S) ------------------------------------------------------------------------------------------------------------------------------------ 2 LUHMAN16AB- WFC3/UVI ACCUM UVIS1 F814W FLASH=12 1 380 S (380 POS TARG -4, 4; SPATIAL RICCIOLO-1 S S) SCAN 0.012, 270.0 Degrees, Forward, 0.45 Arcsec, 6 ------------------------------------------------------------------------------------------------------------------------------------ 3 LUHMAN16AB- WFC3/UVI ACCUM UVIS1 F814W FLASH=12 1 380 S (380 POS TARG -4, -4; SPATIAL RICCIOLO-1 S S) SCAN 0.012, 0.0 Degrees, Forward, 0.45 Arcsec, 6 ------------------------------------------------------------------------------------------------------------------------------------ 4 LUHMAN16AB- WFC3/UVI ACCUM UVIS1 F606W FLASH=12 1 348 S (348 POS TARG 0, 0 RICCIOLO-1 S S) ------------------------------------------------------------------------------------------------------------------------------------ 5 LUHMAN16AB- WFC3/UVI ACCUM UVIS1 F814W FLASH=12 1 380 S (380 POS TARG 4, 4; SPATIAL RICCIOLO-1 S S) SCAN 0.012, 180.0 Degrees, Forward, 0.45 Arcsec, 6 ------------------------------------------------------------------------------------------------------------------------------------ 6 LUHMAN16AB- WFC3/UVI ACCUM UVIS1 F814W FLASH=12 1 380 S (380 POS TARG 4, -4; SPATIAL RICCIOLO-1 S S) SCAN 0.012, 90.0 Degrees, Forward, 0.45 Arcsec, 6 ------------------------------------------------------------------------------------------------------------------------------------ 7 LUHMAN16AB- WFC3/UVI ACCUM UVIS1 F814W FLASH=12 1 60 S (60 POS TARG 4, -4 RICCIOLO-1 S S) ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ LUHMAN16AB-RICCIOLO 1 WFC3/UVI ACCUM UVIS1 F814W none none none none 1 N/A -1 S LUHMAN16AB-RICCIOLO 2 WFC3/UVI ACCUM UVIS1 F814W none none none none 1 N/A -1 S 14330( 6) - 11-Jul-2018 18:23:56 - [ 7] 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 | ------------------------------------------------------------------------------------------------------------------------------------ LUHMAN16AB-RICCIOLO 3 WFC3/UVI ACCUM UVIS1 F814W none none none none 1 N/A -1 S LUHMAN16AB-RICCIOLO 4 WFC3/UVI ACCUM UVIS1 F606W none none none none 1 N/A -1 S LUHMAN16AB-RICCIOLO 5 WFC3/UVI ACCUM UVIS1 F814W none none none none 1 N/A -1 S LUHMAN16AB-RICCIOLO 6 WFC3/UVI ACCUM UVIS1 F814W none none none none 1 N/A -1 S LUHMAN16AB-RICCIOLO 7 WFC3/UVI ACCUM UVIS1 F814W none none none none 1 N/A -1 S 14330( 6) - 11-Jul-2018 18:23:56 - [ 8] Summary Form for Proposal 14330 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures UVIS1 ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/UVIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters FLASH=12 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements BETWEEN 01-OCT-2016 AND 11-OCT-2016, BETWEEN 20-AUG-2018 AND 23-AUG-2018, ORIENT 160D TO 165 D, ORIENT 220D TO 220 D, POS TARG -4, -4, POS TARG -4, 4, POS TARG 0, 0, POS TARG 4, -4, POS TARG 4, 4, SPATIAL SCAN 0.012, 0.0 Degrees, Forward, SPATIAL SCAN 0.012, 0.0 Degrees, Forward, 0.45 Arcsec, 6, SPATIAL SCAN 0.012, 180.0 Degrees, Forward, SPATIAL SCAN 0.012, 180.0 Degrees, Forward, 0.45 Arcsec, 6, SPATIAL SCAN 0.012, 270.0 Degrees, Forward, SPATIAL SCAN 0.012, 270.0 Degrees, Forward, 0.45 Arcsec, 6, SPATIAL SCAN 0.012, 90.0 Degrees, Forward, SPATIAL SCAN 0.012, 90.0 Degrees, Forward, 0.45 Arcsec, 6 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F606W, F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names LUHMAN16AB-RICCIOLO-1, LUHMAN16ABMINAPNE1 ------------------------------------------------------------------------------------------------------------------------------------