16434( 7) - 08-Feb-2021 16:18:59 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 16434 Version: 7 Check-in Time: 08-Feb-2021 16:18:59 STScI Edit Number: 0 Title Imaging of AG Car ------------------------------------------------------------------------------------ Type Cycle GO/DD 28 ------------------------------------------------------------------------------------ Investigators Contact? PI: Christopher Britt Space Telescope Science Institute Y CoI: Max Mutchler Space Telescope Science Institute Y CoI: Quyen Hart Space Telescope Science Institute Y CoI: Joseph DePasquale Space Telescope Science Institute N CoI: Alyssa Pagan Space Telescope Science Institute N CoI: Christine Pulliam Space Telescope Science Institute N CoI: Cheryl Gundy Space Telescope Science Institute N CoI: Holly Ryer (Greathouse) Space Telescope Science Institute N CoI: Ray Villard Space Telescope Science Institute N CoI: Elizabeth Rafferty Space Telescope Science Institute N ------------------------------------------------------------------------------------ Abstract We propose to obtain WFC3 imaging of the Luminous Blue Variable AG Car, and the nebula around it, with 3 medium or broadband filters to image the reflection nebula, as well as the Ha+NII narrowband filter to image the gas around AG Car. ------------------------------------------------------------------------------------ Observations Description ------------------------ We will obtain high signal-to-noise (S/N) imaging of the Luminous Blue Variable AG Car with new broad, medium and narrow band observations from UV to NIR to image the wind outflow and dust reflection nebula using the WFC3/UVIS instrument using the F275W, F547M, F657N, and F845M filters. These new images will complement existing archival observations in F547M and F658N taken with the PC chip of WFPC2. We will obtain new high S/N observations in F657N with WFC3/UVIS to increase the poor S/N of imagery that exists in the archival data as well as add to the outlying nebula which fell off of earlier PC chip exposures. We will also obtain new high S/N observations in F547M, a line-free filter which will show the dust scattering continuum. To better image the structure of the dust in the reflection nebula and maximize the slight color differences in scattered light caused by differences in the dust, we will obtain new medium band observations in F275W and F845M, which are both regions selected for containing no or few emission lines which trace the hot gas rather than scattering dust. The UV capabilities of Hubble will provide a long lever-arm to extract subtle color differences in the scattered light. The bright star in the center of the nebula poses a challenge in reconstructing a public-quality image for release as the bleed trails from the saturated central star will be significant. To mitigate this, we request to schedule observations in both January and February, allowing the instrument to rotate between observations and sending the bleed trail to different parts of the nebula. In this way, images from each epoch can be combined and the bleed trails removed without losing detail in the nebula. In addition to archival F547M and F658N 16434( 7) - 08-Feb-2021 16:18:59 - [ 2] imaging, there exist archival FOS spectra and IUE spectra of AG Car and its nebula, which can be used to help guide exposure time calculations for F275W observations. AG Car is 10x timesfainter at 2800A than the frequently observed Eta Car, which was featured in a press release using F280N imaging in July, 2019. This suggests that the brightness difference is almost entirely due to the distance, as AG Car is 3x further away. Eta Car was observed with 3930s in F280N, which is 10x narrower than F275W. We here propose to use 4 orbits in F275W, two in January and two in February, to obtain a high S/N image of AG Car in F275W. The archival images in F658N totaled 1200s. Archival F547M images total 4200s. An additional 3 orbits each in January and in February for F547M, F657N, and F845M, would provide high S/N images in each filter and extend the coverage of the outer nebula which fell off the PC chip in archival observations. 6 orbits for optical observations in F547M, F657N, and F845M and 4 orbits for F275W gives a total of 10 orbits. Scheduling windows for AG Car are in early January and late February. In order to best treat the large bleed trails from the central star in the final image, we request to do half of our orbits in January and half in late February, so that the angle of the detector on the sky changes and takes the bleed trail (and large diffraction spikes) to another location in the nebula, allowing the data from one month to fill in the resulting gap in the other. ------------------------------------------------------------------------------------ 16434( 7) - 08-Feb-2021 16:18:59 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 AG-CAR STAR, LUMINOUS BLUE RA=10H56M11.5681S, J2000 V = 6.96 VARIABLE DEC=-60D27'12.78" Reference Frame: Other: SIMBAD Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2015.5 -6.355335037111536E-4 0.001873 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 16434( 7) - 08-Feb-2021 16:18:59 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 4 Primary_Pattern Secondary_Pattern Pattern_Type LINE Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 2.5 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 86 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 5 Primary_Pattern Secondary_Pattern Pattern_Type LINE Pattern_Purpose DITHER Number_Of_Points 3 Point_Spacing 2.5 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 86 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 6 Primary_Pattern Secondary_Pattern Pattern_Type LINE Pattern_Purpose DITHER Number_Of_Points 2 Point_Spacing 2.5 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 86 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 16434( 7) - 08-Feb-2021 16:18:59 - [ 5] Visit: 01 Visit Requirements: ORIENT 301D TO 309 D 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 AG-CAR WFC3/UVI ACCUM UVIS2-FIX F275W FLASH=15 1 1400 S PATTERN 4 1 S (5600 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 | ------------------------------------------------------------------------------------------------------------------------------------ AG-CAR 1 WFC3/UVI ACCUM UVIS2-FI F275W 1 none none none 1 N/A S X AG-CAR 1 WFC3/UVI ACCUM UVIS2-FI F275W 2 none none none 1 N/A S X AG-CAR 1 WFC3/UVI ACCUM UVIS2-FI F275W 3 none none none 2 N/A S X AG-CAR 1 WFC3/UVI ACCUM UVIS2-FI F275W 4 none none none 2 N/A S X 16434( 7) - 08-Feb-2021 16:18:59 - [ 6] Visit: 02 Visit Requirements: SAME ORIENT AS 01 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 AG-CAR WFC3/UVI ACCUM UVIS2-FIX F547M FLASH=8 1 700 S PATTERN 5 1-3 S (2100 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 AG-CAR WFC3/UVI ACCUM UVIS2-FIX F657N FLASH=16 1 1200 S S (3600 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 AG-CAR WFC3/UVI ACCUM UVIS2-FIX F845M FLASH=12 1 700 S S (2100 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 | ------------------------------------------------------------------------------------------------------------------------------------ AG-CAR 1 WFC3/UVI ACCUM UVIS2-FI F547M 1 none none none 1 N/A S X AG-CAR 1 WFC3/UVI ACCUM UVIS2-FI F547M 2 none none none 2 N/A S X AG-CAR 1 WFC3/UVI ACCUM UVIS2-FI F547M 3 none none none 3 N/A S X AG-CAR 2 WFC3/UVI ACCUM UVIS2-FI F657N 1 none none none 1 N/A S X AG-CAR 2 WFC3/UVI ACCUM UVIS2-FI F657N 2 none none none 2 N/A S X AG-CAR 2 WFC3/UVI ACCUM UVIS2-FI F657N 3 none none none 3 N/A S X AG-CAR 3 WFC3/UVI ACCUM UVIS2-FI F845M 1 none none none 1 N/A S X AG-CAR 3 WFC3/UVI ACCUM UVIS2-FI F845M 2 none none none 2 N/A S X AG-CAR 3 WFC3/UVI ACCUM UVIS2-FI F845M 3 none none none 3 N/A S X 16434( 7) - 08-Feb-2021 16:18:59 - [ 7] Visit: 03 Visit Requirements: ORIENT 352D TO 359.9 D 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 AG-CAR WFC3/UVI ACCUM UVIS1-FIX F275W FLASH=20 1 100 S (200 PATTERN 6 1-3 S S) ------------------------------------------------------------------------------------------------------------------------------------ 2 AG-CAR WFC3/UVI ACCUM UVIS1-FIX F275W FLASH=15 1 1400 S S (2800 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 AG-CAR WFC3/UVI ACCUM UVIS1-FIX F657N FLASH=15 1 1200 S S (2400 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 | ------------------------------------------------------------------------------------------------------------------------------------ AG-CAR 1 WFC3/UVI ACCUM UVIS1-FI F275W 1 none none none 1 N/A S X AG-CAR 1 WFC3/UVI ACCUM UVIS1-FI F275W 2 none none none 2 N/A S X AG-CAR 2 WFC3/UVI ACCUM UVIS1-FI F275W 1 none none none 1 N/A S X AG-CAR 2 WFC3/UVI ACCUM UVIS1-FI F275W 2 none none none 2 N/A S X AG-CAR 3 WFC3/UVI ACCUM UVIS1-FI F657N 1 none none none 1 N/A S X AG-CAR 3 WFC3/UVI ACCUM UVIS1-FI F657N 2 none none none 2 N/A S X 16434( 7) - 08-Feb-2021 16:18:59 - [ 8] Visit: 04 Visit Requirements: SAME ORIENT AS 03 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 AG-CAR WFC3/UVI ACCUM UVIS1-FIX F547M FLASH=12 1 700 S PATTERN 5 1-3 S (2100 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 AG-CAR WFC3/UVI ACCUM UVIS1-FIX F657N FLASH=16 1 1200 S S (3600 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 AG-CAR WFC3/UVI ACCUM UVIS1-FIX F845M FLASH=12 1 700 S S (2100 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 | ------------------------------------------------------------------------------------------------------------------------------------ AG-CAR 1 WFC3/UVI ACCUM UVIS1-FI F547M 1 none none none 1 N/A S X AG-CAR 1 WFC3/UVI ACCUM UVIS1-FI F547M 2 none none none 2 N/A S X AG-CAR 1 WFC3/UVI ACCUM UVIS1-FI F547M 3 none none none 3 N/A S X AG-CAR 2 WFC3/UVI ACCUM UVIS1-FI F657N 1 none none none 1 N/A S X AG-CAR 2 WFC3/UVI ACCUM UVIS1-FI F657N 2 none none none 2 N/A S X AG-CAR 2 WFC3/UVI ACCUM UVIS1-FI F657N 3 none none none 3 N/A S X AG-CAR 3 WFC3/UVI ACCUM UVIS1-FI F845M 1 none none none 1 N/A S X AG-CAR 3 WFC3/UVI ACCUM UVIS1-FI F845M 2 none none none 2 N/A S X AG-CAR 3 WFC3/UVI ACCUM UVIS1-FI F845M 3 none none none 3 N/A S X 16434( 7) - 08-Feb-2021 16:18:59 - [ 9] Summary Form for Proposal 16434 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures UVIS1-FIX, UVIS2-FIX ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/UVIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters FLASH=12, FLASH=15, FLASH=16, FLASH=20, FLASH=8 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 301D TO 309 D, ORIENT 352D TO 359.9 D, PATTERN 4 1, PATTERN 5 1-3, PATTERN 6 1-3, SAME ORIENT AS 01, SAME ORIENT AS 03 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F275W, F547M, F657N, F845M ------------------------------------------------------------------------------------------------------------------------------------ Target Names AG-CAR ------------------------------------------------------------------------------------------------------------------------------------