15892( 3) - 08-Apr-2020 13:30:23 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 15892 Version: 3 Check-in Time: 08-Apr-2020 13:30:23 STScI Edit Number: 0 Title Probing the Jet at the Heart of the Coldest Object in the Universe ------------------------------------------------------------------------------------ Type Cycle GO 27 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Raghvendra Sahai Jet Propulsion Laboratory Y CoI: Prof. Wouter Vlemmings Chalmers University of Technology/Onsala N Space Obs. CoI: Dr. Lars-Angstrom ke Nyman European Southern Observatory - Germany N CoI: Prof. Eric Blackman University of Rochester N ------------------------------------------------------------------------------------ Abstract The Boomerang Nebula, is the coldest (naturally occurring) object in the Universe. CO(1-0) observations of it show a massive ultra-cold outflow in absorption against the microwave background, implying that the nebula has cooled below the temperature of the cosmic background radiation. Its extreme properties make it the Rosetta Stone for understanding the mass-loss processes that govern late stellar evolution. Our recent ALMA study shows that the Boomerang is the product of a common-envelope event (CEE) in a binary system, while the primary was an RGB/early-AGB star, which ejected the primary's envelope that now forms the ultra-cold outflow. It is likely that the companion merged into the primary's core, leaving a single G-type star with a large dusty disk. This disk may be the launch site of a jet that has sculpted the inner regions of the ultra-cold outflow, producing the bipolar nebula at the center. HST polarised-light imaging shows the presence of two point-symmetric spurs around the central star, that likely result from such a jet. Previous ground-based spectroscopy shows absorption and emission lines that are likely associated with this jet. We propose to obtain long-slit spectroscopy with STIS in order to confirm the presence of the jet and probe its spatio-kinematic structure. These data will provide us with unprecedented details of the product of a CEE event, and the launching of jets from the central source - a fundamental, yet very poorly understood astrophysical process. Our analysis will use the results of a recent theoretical study that shows how one can constrain basic properties of the jet engine by studying the jet properties. ------------------------------------------------------------------------------------ 15892( 3) - 08-Apr-2020 13:30:23 - [ 2] Observations Description ------------------------ We will use STIS with G750M centered at 6581\, \AA~and a mosaic of 10 parallel slits aligned along the axis of the central bipolar nebula (i.e. PA=353\arcdeg), to probe the spatio-kinematic structure of the jet and shocked regions where it impacts the walls of the bipolar cavity. We will use the the $52{''}\times$0\farcs2 slit to obtain spectra in the $\lambda\lambda$6295-6867\, \AA range with $\sim$50\, \kms~spectral and 0.05 arcsec spatial resolution. We will thus cover the H$\alpha$, [NII]\, 6548, 6583 and [SII]\, 6717, 6731 lines, the [OI]6300 line will be near the edge, but still visible. The average H$\alpha$, [NII] and [SII] average line intensities are in the range $\sim3.5\times10^{-15}-1.5\times10^{-15}$ erg\, s$^{-1}$\, cm$^{-2}$\, arcsec$^{-2}$. The line-widths (marginally resolved) are about $70-90$\, \kms. Since the line intensities are likely not uniform, we assume a variation of a factor 3, and a minimum S/N ratio of about 10 in the regions of lowest intensity in our weakest lines, i.e., [SII]\, 6717, 6731, which are important for measuring the densities in the jet; the S/N obtained on the H$\alpha$ absorption line will be larger. A high S/N for the latter is important, as it is the only tracer that we have for the unshocked gas in the jet. Using the STIS Exposure Time Calculator, we estimate that an exposure time of about 1100\, s will be needed. Thus, for our mosaic of 10 slits, we will need 183 minutes of exposure time, i.e., 4 orbits (with 50\, min per orbit to allow increase in Scheduling Flexibility, as per the APT). From the observed PA of the bipolar nebula (353\arcdeg), we compute an $ORIENT=PA+46.3\arcdeg\sim39\arcdeg$ or $PA+226.3\arcdeg\sim219\arcdeg$ (as per the STIS handbook). We therefore request a slit ORIENT range $PA=34\arcdeg-44\arcdeg$, or $214\arcdeg-224\arcdeg$, in order to probe the emission from the highly-collimated jet precisely. This ORIENT range, although restricted, allows a substantial $\gtrsim$1-month long window for scheduling. ------------------------------------------------------------------------------------ 15892( 3) - 08-Apr-2020 13:30:23 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 IRAS12419-54 STAR, POST-AGB STAR RA=12H44M46.0900S, J2000 V = 12.8 +/- 0.3 14 DEC=-54D31'13.36" Reference Frame: ICRS Extended: YES ------------------------------------------------------------------------------------------------------------------------------------ 15892( 3) - 08-Apr-2020 13:30:23 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type STIS-PERP-TO-SLIT STIS-ALONG-SLIT Pattern_Purpose MOSAIC DITHER Number_Of_Points 10 3 Point_Spacing 0.2 0.380325 Line_Spacing Coordinate_Frame POS-TARG POS-TARG Pattern_Orient 0.0 90.0 Angle_Between_Sides Center_Pattern YES NO Pattern_Comments: pattern should produce a mosaice of 10 parallel slits, with a grid spacing of 0.2 arcsec for each slit location, there should be 3 dithered exposures ------------------------------------------------------------------------------------------------------------------------------------ 15892( 3) - 08-Apr-2020 13:30:23 - [ 5] Visit: 01 Visit Requirements: PCS MODE FINE; SCHED 30%; ORIENT 34D TO 44 D; ORIENT 214D TO 224 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 IRAS12419-5 STIS/CCD ACQ F28X50LP MIRROR ACQTYPE=POINT 1 0.5 S (0.5 414 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 IRAS12419-5 STIS/CCD ACCUM 52X0.2 G750M 6581 1 200 S PATTERN 1 2 414 see below (7872 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 | ------------------------------------------------------------------------------------------------------------------------------------ IRAS12419-5414 1 STIS/CCD ACQ F28X50LP MIRROR none none none none 1 N/A IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 1 1 none 1 1 136.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 1 1 none 2 1 136.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 1 2 none 1 1 136.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 1 2 none 2 1 136.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 1 3 none 1 1 136.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 1 3 none 2 1 136.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 2 1 none 1 1 136.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 2 1 none 2 1 136.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 2 2 none 1 1 136.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 2 2 none 2 1 136.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 2 3 none 1 1 136.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 2 3 none 2 1 136.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 3 1 none 1 2 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 3 1 none 2 2 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 3 2 none 1 2 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 3 2 none 2 2 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 3 3 none 1 2 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 3 3 none 2 2 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 4 1 none 1 2 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 4 1 none 2 2 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 4 2 none 1 2 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 4 2 none 2 2 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 4 3 none 1 2 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 4 3 none 2 2 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 5 1 none 1 2 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 5 1 none 2 2 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 5 2 none 1 2 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 5 2 none 2 2 130.0 S 15892( 3) - 08-Apr-2020 13:30:23 - [ 6] 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 | ------------------------------------------------------------------------------------------------------------------------------------ IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 5 3 none 1 3 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 5 3 none 2 3 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 6 1 none 1 3 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 6 1 none 2 3 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 6 2 none 1 3 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 6 2 none 2 3 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 6 3 none 1 3 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 6 3 none 2 3 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 7 1 none 1 3 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 7 1 none 2 3 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 7 2 none 1 3 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 7 2 none 2 3 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 7 3 none 1 3 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 7 3 none 2 3 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 8 1 none 1 3 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 8 1 none 2 3 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 8 2 none 1 4 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 8 2 none 2 4 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 8 3 none 1 4 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 8 3 none 2 4 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 9 1 none 1 4 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 9 1 none 2 4 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 9 2 none 1 4 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 9 2 none 2 4 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 9 3 none 1 4 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 9 3 none 2 4 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 10 1 none 1 4 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 10 1 none 2 4 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 10 2 none 1 4 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 10 2 none 2 4 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 10 3 none 1 4 130.0 S IRAS12419-5414 2 STIS/CCD ACCUM 52X0.2 G750M 6581 10 3 none 2 4 130.0 S 15892( 3) - 08-Apr-2020 13:30:23 - [ 7] Summary Form for Proposal 15892 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures 52X0.2, F28X50LP ------------------------------------------------------------------------------------------------------------------------------------ Configurations STIS/CCD ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, ACQ ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters ACQTYPE=POINT ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 214D TO 224 D, ORIENT 34D TO 44 D, PATTERN 1 2, PCS MODE FINE, SCHED 30% ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements G750M, MIRROR ------------------------------------------------------------------------------------------------------------------------------------ Target Names IRAS12419-5414 ------------------------------------------------------------------------------------------------------------------------------------