12186( 3) - 07-Sep-2010 16:59:05 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 12186 Version: 3 Check-in Time: 07-Sep-2010 16:59:05 STScI Edit Number: 0 Title Jet launching and evolution in the weakly magnetized Herbig Ae star HD 163296 ------------------------------------------------------------------------------------ Type Cycle GO 18 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Hans Moritz Guenther Smithsonian Institution Astrophysical Observatory CoI: Dr. Scott J. Wolk Smithsonian Institution Astrophysical N Observatory CoI: Mr. Christian P. Schneider Universitat Hamburg, Hamburger Sternwarte N ------------------------------------------------------------------------------------ Abstract Jets are common in young stars, however, their driving mechanism and many details about their evolution are still unknown. We propose to reobserve HH 409, the jet driven by the Herbig Ae star HD 163296. One orbit each will be used for optical (G750M, covering Ha and the density and temperature sensitive forbidden lines [OI], [SII] and [NII]) and FUV (G140M, covering Lya) long-slit spectroscopy with STIS. Similar HST data were taken between 1998 and 2003 already. Comparing archival to new observations we have a long time baseline to study the evolution of velocity, temperature and density in the Herbig-Haro objects of the jet. We can infer their energy budget from radiative cooling, expansion and continuous shock reheating. Furthermore, we will spectrally resolve the emission lines. If a high-velocity component is found, we can rule out disk winds as jet launching scenario. HH 409 is the only jet with detected X-ray emission from a young star with a weak magnetic field. ------------------------------------------------------------------------------------ Observations Description ------------------------ We ask for 2 orbits of HST time to measure i) the position and ii) the spectrum of the HH objects. All proposed HST observations closely resemble existing observations. Those observations show that no safety contraint will be violated. We expect the position of the emitting gas to change, but as best estimate we base our exposure time calculation on the existing data. At the declination of HD 163296 the usable time is 54 min per orbit. Target acquisition including acquisition exposures requires roughly 10 min, so in each orbit we can take a single long-slit exposure of 2700 s. We request a full orbit with the G750M grating with central wavelength 6581 A on the 50???0.2?? slit, positioning the central star behind the occulting bar to reduce the risk of stray light (aperture 52X0.2F1). In contrast to dataset O5FO22010 the higher resolution of the G750M grating allows us to separate [S ii] 6716 A and [S ii] 6731 A. To estimate the SNR ratio we use the line fluxes from an G750L observation of 1440 s (dataset O5FO22010, Wassell et al. 2006); the data is shown in Fig. 4 of the science justification. In [Oi] 6300 A and [Nii] 6584 A we will reach a signal to noise ratio (SNR) of 5-10 for knot A, which was fainter than knot B and C in the existing observations. In Halpha we 12186( 3) - 07-Sep-2010 16:59:05 - [ 2] will reach SNR of 30 in the line center and 15 in the fast component, assuming that the line width is 500 km/s. Thus we can easily split the flux in different velocity components. We propose to observe the FUV lines with the G140M grating, central wavelength 1218 A, for one full orbit. We will use the 50???0.2?? slit. This exactly replicates the set-up of an observation taken on 1999-09-30 15:16:27 (dataset O57Z03010). That observation was published by Devine et al. (2000); the data is shown in Fig. 2 of the science justification. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- The BOT warns me of bright objects, which might damage the detector. That is OK, the bright object is actually HD 163296 be very target we want to observe (or more preciely, we want to observe the jet from HD 163296). This is why we place the central star behind the occulting bar for the spectrocopy and perfrom the target acquisition with a narrow band filter. Observatiosn of very similar layout on the same object have been done with STIS before without any detector damage. ------------------------------------------------------------------------------------ 12186( 3) - 07-Sep-2010 16:59:05 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 HD-163296 STAR, CIRCUMSTELLAR RA=17H56M21.2879S +/- 0.01", J2000 V = 6.871 MATTER, HERBIG AE/BE, DEC=-21D57'21.88" +/- 0.01" JET Reference Frame: ICRS 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) 2000 -5.843850057091823E-4 -0.04043 0.00819 ------------------------------------------------------------------------------------------------------------------------------------ 12186( 3) - 07-Sep-2010 16:59:05 - [ 4] Visit: 01 Visit Requirements: ORIENT 88.3D TO 90.3 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| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 HD-163296 STIS/CCD ACQ F28X50OII MIRROR ACQTYPE=POINT 1 2 S ------------------------------------------------------------------------------------------------------------------------------------ 2 HD-163296 STIS/CCD ACCUM 52X0.2F1 G750M 6581 CR-SPLIT=3 1 2000 S see below ------------------------------------------------------------------------------------------------------------------------------------ 3 HD-163296 STIS/FUV TIME-TA 52X0.2F1 G140M 1218 BUFFER-TIME=1000 1 2700 S -MAMA G see below ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ HD-163296 1 STIS/CCD ACQ F28X50OI MIRROR none none none none 1 N/A I HD-163296 2 STIS/CCD ACCUM 52X0.2F1 G750M 6581 none none none 1 1 758.0 S HD-163296 2 STIS/CCD ACCUM 52X0.2F1 G750M 6581 none none none 2 1 758.0 S HD-163296 2 STIS/CCD ACCUM 52X0.2F1 G750M 6581 none none none 3 1 759.0 S HD-163296 3 STIS/FUV TIME-TA 52X0.2F1 G140M 1218 none none none none 2 2997.0 S -MAMA G 12186( 3) - 07-Sep-2010 16:59:05 - [ 5] Summary Form for Proposal 12186 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures 52X0.2F1, F28X50OII ------------------------------------------------------------------------------------------------------------------------------------ Configurations STIS/CCD, STIS/FUV-MAMA ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, ACQ, TIME-TAG ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters ACQTYPE=POINT, BUFFER-TIME=1000, CR-SPLIT=3 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 88.3D TO 90.3 D ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements G140M, G750M, MIRROR ------------------------------------------------------------------------------------------------------------------------------------ Target Names HD-163296 ------------------------------------------------------------------------------------------------------------------------------------