0 Assigned ID: 520 ----- Attempting Submission 1 (Fri Apr 10 15:44:52 GMT 2015) ----- HST Phase I Proposal 520 (grb080517.prop.apt) successfully submitted. Receipt: # 520-1 We would appreciate careful checking of our phase II since the PI is relatively inexperienced at setting up Hubble observations. -362219266 ----- Attempting Submission 1 (Wed Jul 22 16:36:02 GMT 2015) ----- Gamma ray bursts (GRBs) are potentially observable to the highest redshift, but their interpretation relies on a knowledge of their hosts and environment. GRB hosts are identified by a single stellar explosion which allows strong statistical statements on the global star formation distribution. However making these relies on local, low redshift exemplars in which the conditions giving rise to bursts can be studied. Unfortunately such sources are rare. We have identified an unusual, dusty GRB host in the local universe (host of low-luminosity GRB 080517 at z=0.09) which shows strong star formation and is exceptionally luminous in the infrared. It is also within 25 kpc and a few hundred km/s of a neighbouring galaxy, itself undergoing a merger. In this programme we wish to map this system in the ultraviolet and infrared. We will evaluate evidence for clumpy star formation and tidal interactions between the two galaxies, determining whether galaxy interactions may have contributed to the starbursts in both galaxies, and assessing whether this may have played a role in triggering the burst. If so, it is likely that the role of clustering and larger scale environment needs to be reassessed in inferences drawn from the redshift distribution of GRBs. We requested 1 orbit, to include WFC3 observations in UVIS/F275W (~1235s on target), IR/F098M (200s) and IR/F160W (200s) of a single target field which is centred on the host galaxy of GRB 080517. We were allocated the 1 orbit requested. While the GRB host (on which our pointing is centered) is the primary target, we are also interested in a neighbouring source, 17 arcsec to the North-East, with which we believe it to be interacting. Both are visible in DSS imaging. In Phase II, we have updated the integration times to allow for dithering of the telescope (using standard dither patterns), and to pack the orbit in order to maximise science. The F275W observation is divided into three dithered sub-exposures, each flashing the chip to minimise background. These are specified in the UVIS2 aperture, while placing the target near the corner of the chip for charge transfer efficiency (which previous experience by our team suggests is important). This choice of aperture and target placement restricts our range of roll angles in order to ensure both sources are comfortably on the chip. The two IR observations are each divided into two dithered sub-exposures. These are centred on the IR chip to allow for any roll angle and have had total integration times increased to improve depth and prevent downtime due to buffer dump. We would appreciate careful checking of our programme, since the PI is relatively inexperienced at specifying a Hubble Phase II. UNRESOLVED STELLAR POPULATIONS AND GALAXY STRUCTURE 12 false true false false SUPPORTED GALAXY INTERACTING GALAXY STARBURST J2000 J2000 WFC3/UVIS Imaging No No F275W WFC3/IR Imaging No No F098M WFC3/IR Imaging No No F160W POS-TARG DITHER 0.135 LINE false false 3 46.84 WFC3-UVIS-DITHER-LINE-3PT 1 false POS-TARG DITHER 0.636 LINE false false 2 41.788 WFC3-IR-DITHER-LINE 2 false The scheduling data was generated by CASM 23.2. CASM was run in Phase II mode. 1437582816870 /private/var/folders/bd/4m9splvs5bz385z_4wrg1c9c0000gn/T/OPVisit3325539563530672824.xml (Tic-Visit :proposal-id 14276 :visit-id "01" :proposal-version -1 :trans-version "20150609" :date "22-Jul-2015 17:33:36.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 1562608 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14276 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14276 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 3067 :al-overhead-at-end 0 :internal-dur-at-end 614 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3403 :pcs-gap 0 ) true 1 0