Assigned ID: 518 ----- Attempting Submission 1 (Fri Feb 26 19:21:35 GMT 2010) ----- HST Phase I Proposal 518 (HDXXX.apt) successfully submitted. ----- Attempting Submission 2 (Fri Feb 26 22:04:47 GMT 2010) ----- HST Phase I Proposal 518 (HDXXX.apt) successfully submitted. Dear Van, I checked the exposure times for the ACQ exposure. We should achieve S/N=200 in 0.6 s and reach saturation after 3.6 s. As you suggested I now put an exposure time of 2 s, which is midway between those values. I deleted the ACQ/PEAK exposure. That also gives us an additional 161 s for science. Thanks a lot for your help! Yours, Moritz ----- Attempting Submission 1 (Tue Jul 06 15:28:08 GMT 2010) ----- HST Phase II Proposal 12186 (HDXXX_1visit.apt) successfully submitted. ----- Attempting Submission 2 (Tue Sep 07 16:30:20 GMT 2010) ----- HST Phase II Proposal 12186 (HDXXX_1visit.apt) successfully submitted. ----- Attempting Submission 3 (Tue Sep 07 16:31:29 GMT 2010) ----- 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.

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 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. 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. STAR FORMATION 12 false 0.0 0.0 false false false false false false SUPPORTED STAR CIRCUMSTELLAR MATTER HERBIG AE/BE JET This object was generated by the targetselector and retrieved from the SIMBAD database. J2000 17 56 21.2879 -21 57 21.88 J2000 STIS/FUV-MAMA Spectroscopic No No G140M 1218 STIS/CCD Spectroscopic No No G750M 6581 /data/hguenther/my_proposals/HST/OP-cache/HDXXX_1visit-v01.xml 1283876139260 The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. (Tic-Visit :proposal-id 12186 :visit-id "01" :proposal-version -1 :trans-version "20100505" :date "07-Sep-2010 12:15:39.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 336000 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12186 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12186 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2916 :al-overhead-at-end 75 :internal-dur-at-end 2166 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3249 :pcs-gap 0 ) (Tic-Orbit :proposal-id 12186 :visit-id "01" :orbit-number 2 :pcs-time 222 :si-vis-utilization 3027 :al-overhead-at-end 0 :internal-dur-at-end 681 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3249 :pcs-gap 0 ) true 2 0