0 Assigned ID: 695 ----- Attempting Submission 1 (Fri Apr 10 19:13:27 GMT 2015) ----- P2 has been prepared by Co-PI Mike Gladders at UChicago. -153738444 ----- Attempting Submission 1 (Sun Jul 19 06:42:30 GMT 2015) ----- We propose to image the Ly-alpha and stellar continuum emission for an exceptionally bright lensed main-sequence galaxy at z=2.39. Its chance alignment close to a natural guide star (very rare for arcs in cluster environments) has allowed high signal-to-noise SINFONI+AO observations of all the rest-frame optical diagnostic emission lines ([OIII], H-beta, [OI], H-alpha, [NII] and [SII]). We find an underlying broad component with FWHM~740 km/s in both the Balmer and forbidden lines, and measure line ratios which place the outflow robustly in the region of the BPT diagrams associated with AGN ionisation. At this redshift, Ly-alpha uniquely falls in the F410M WFC3 medium-band filter. With a modest investment of six orbits, we will map the Ly-alpha emission and stellar UV continuum of this source at spatial scales ~<100 pc - similar resolution to the SINFONI+AO data. This will allow us to compare the spatial extent and morphology (smooth or clumpy) of the Ly-alpha, UV and dust-corrected H-alpha emission and disentangle the effects of star formation and AGN ionisation on each tracer. This is a truly unique opportunity where a combination of gravitational lensing, AO guide star, the right source redshift, and the presence of a weak AGN allow a complete and magnified view of three main tracers of the physical conditions and structure of the interstellar medium in a star-forming galaxy at cosmic noon. This 5 orbit observation of a lensed AGN-hosting galaxy is intended to 1. measure the the Ly-A emission map of the galaxy using the F410M filter, in which the emission line is well-centered; 2. measure the continuum emission of the galaxy using four broad band filters spanning the available wavelength space redward of the Ly-A line (F555W,F814W,F105W,F140W). 3. search for an characterize secondary lensed features - of this galaxy , or others - that will aid in the reconstrcution of the lens mass model, critical to system characterization The primary lensed source is remarkably bright, and so exposure time, per se, is not the dominant concern for the broad band observations. Rather, PSF reconstruction, and rejection of defects and cosmic rays is more of a concern. Extensive previous experience suggests an integration ratio of ~ 2-2.5 to 1 for UVIS to IR works very well for high-z lensed galaxies, and we aim for that here. Based pon existing ground based data, the lensing appears to be due to a sub-cluster offset from the core of a main galaxy cluster. Since information about the main cluster (photometry, possibly weak and/or or strong lensing signals) is of benefit to the lensing reconstruction of the targeted source, and becasue the sub-and main clusters can both be imaged in the same field, we have arranged the pointing to include both. This has the added benefit of moving the main lensed galaxy target off the center of the field, toward the readout registers in the UVIS channel, which aids in suppressing CTE loss effects. A further issue is a consequence of the situation that makes this target so particularly compelling - namely that it has a bright (13th-15th mag, depending on filter) star quite nearby (<10"). Thus keeping exposures as reasonably short as possible (to avoid bleeding, minimize persistence etc), without otherwise compromising data quality via read noise etc, is important. The peak pixel counts are very similar in the IR channels - only very slightly brighter in F105W. The plan sketched below and implemented here in APT yields peak counts per pixel at about 1-3 x 10^6 (all values from BOT, much lower in the mid-band F410M filter). We have carefully evaluated the ghosting, diffraction spikes, and bleeding that can/do occur with such data, by examining in detail similarly bright stars in familiar data taken using similar strategies from the Large program GO13003 (PI:Gladders). In all filters the biggest issue is diffraction spikes from the secondary supports. After that, filters ghosts are a concern in some cases, and in probably one UVIS filter very modest bleeding from saturation. For the IR channel there is the additional issue of persistence. In addition to the primary image of the lensed source, there are numerous possible secondary images suggested in the ground-based data, as well as a number of lensed galaxies; all of these must be characterised with the best possible fidelity to ensure best science return. Putting this all together we have chosen a specific orient to place the primary lensed image as well as all suggested possible secondary features, and lens galaxies, in regions free of both diffraction spikes and ghosts. NOTE - though this is a highly constrained roll angle, it is not itself highly constraining, as the are nearly 180 days available on this target for that angle, according to the Visit Roll Angle report. There various considerations lead to the following plan: 1) We break the 5 orbits up into 2 visits of 3 and 2 orbits respectively. Each visit gets some F410M imaging, plus all the imaging for one IR filter, and one UVIS broadband filter (in the first orbit of the visit). 2) The 3 orbit visit contains 7 IR subframes, done at the start of each orbit, in a 3, 2, 2 arrangement. These are the shortest IR images (SPARS25, NSAMP=5) and are assigned to the filter in which the nearby star will be brightest (F105W). The two orbit visit contains 5 IR subframes, done at the start of each orbit, in a 3, 2 arrangement. These are SPARS25, NSAMP=7 and are assigned to the other IR filter F140W. Total integrations times are 712, 765 sec in F105W, F140W respectively. Dither patterns are simple 3pt line dithers for the 3-image orbits, and 2-point dithers for the 2-image orbits. This will yield reasonable PSF reconstruction, but keeps dithers small to avoid persistance spreading spatially. We do not require ultra-precise photometry, and are confident (based on past experience again) that we can flat-field out IR blobs to a level sufficent for our purposes. The IR 'death star' feature is also not of concern to us. Since the contiguous inter-orbit pointing stability is beter than about 0.2 IR pixels, we also include a small POSTARG offset in the 3-orbit visit in order to further optimize the PSF sampling in the IR. 3) The first orbit in each visit, in addition to the beginning section with IR images, contains 4 UVIS broad band images. F555W is more sensitive, per second, than F814W, and so is placed in the 2-orbit visit where the IR imaging takes somewhat more time, and hence the F555W images are slightly shorter duration than the F814W images. Total integration times are 1748, 1900 sec in F555W, F814W respectively. The dither pattern is a single step across the chip gap, with a sub-pixel dither at each position. We have used this exact pattern effectively in other programs. 4) the remaining 2nd and 3rd orbits in one visit, and the 2nd orbit in the other, are assigned to F410M imaging. Since this is a filter only a few hundred A wide, we wish to minimize the impact of readnoise (and added noise from FLASH) while at the same time maximising PSF reconstruction, defect rejection, etc. Since there are three near-empty orbits available for this imaging, we simply use 2 exposures per orbit, each about 1200 sec long. The total integration time achieved is 7258 seconds. We use a simple 2-point line-dither for each image pari in one orbit, noting that the contiguous inter-orbit pointing undertainting is 0.13-0.5 UVIS pixels (WFC3-2010-09), and so there is little point in attempting any more complex dither strategies here. We DO however add a simple POSTARG offset in Y of (0,1.2,-1.2) across the available three orbits in order to bridge the UVIS chip gap: this isn't relevant for the primary target, but costs basically nothing in exposure time, so we err on the conservative here. 5) In all cases, on the UVIS side, FLASH is used if flagged by APT, to achieve a 12 count background level. ISM IN EXTERNAL GALAXIES 12 false false false false SUPPORTED GALAXY GRAVITATIONAL LENS HIGH REDSHIFT GALAXY QUASAR J2000 J2000 WFC3/UVIS Imaging No No F410M WFC3/UVIS Imaging No No F555W WFC3/UVIS Imaging No No F814W WFC3/IR Imaging No No F105W WFC3/IR Imaging No No F140W POS-TARG DITHER 0.145 LINE false false 2 46.84 WFC3-UVIS-DITHER-LINE 1 false POS-TARG DITHER 0.605 LINE false false 3 41.788 WFC3-IR-DITHER-LINE-3PT 7 false POS-TARG MOSAIC DITHER 2 2.4 WFC3-UVIS-MOS-DITH-LINE false true 0.119 2 85.754 POS-TARG WFC3-UVIS-MOS-DITH-LINE 33.606 8 true POS-TARG DITHER 0.636 LINE false false 2 41.788 WFC3-IR-DITHER-LINE 9 false 1437287921490 /Users/gladders/Desktop/OP-cache/0033try2-v01.xml The scheduling data was generated by CASM 23.2. CASM was run in Phase II mode. 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CASM was run in Phase II mode. (Tic-Visit :proposal-id 14170 :visit-id "02" :proposal-version -1 :trans-version "20150609" :date "19-Jul-2015 01:39:05.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 2428848 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14170 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14170 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2875 :al-overhead-at-end 119 :internal-dur-at-end 31 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3210 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14170 :visit-id "02" :orbit-number 2 :pcs-time 222 :si-vis-utilization 2987 :al-overhead-at-end 122 :internal-dur-at-end 668 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3210 :pcs-gap 0 ) true 2 0