14593( 2) - 18-Jul-2016 15:36:49 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 14593 Version: 2 Check-in Time: 18-Jul-2016 15:36:49 STScI Edit Number: 0 Title Constraining the Origin of Multiple Populations in Globular Clusters ------------------------------------------------------------------------------------ Type Cycle GO 24 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Nate Bastian Liverpool John Moores University Y CoI: Dr. Marina Rejkuba European Southern Observatory - Germany N CoI: Dr. Michael Hilker European Southern Observatory - Germany N CoI: Dr. Ben Davies Liverpool John Moores University N CoI: Mr. Ivan Cabrera-Ziri Liverpool John Moores University N CoI: Ms. Katie Hollyhead Liverpool John Moores University N ------------------------------------------------------------------------------------ Abstract Ancient Globular Clusters (GCs), once thought to be the quintessential single stellar population, are now known to host multiple populations, with varying metal (and presumably helium) content between stars. Many scenarios have been put forward to explain the presence of the multiple populations, several of which rely on multiple generations of stars, with the first generation chemically enriching further generations. Testing these scenarios is difficult as nearby young clusters, that can be resolved into their constituent stars, do not show age/abundance spreads. It has been suggested that this is the case because the young clusters are not massive enough (>5*10^5 Msun) to hold onto their stellar ejecta, and hence follow a different evolutionary path than GCs. We propose UV imaging of a sample of massive (>10^6 Msun) young (50-500 Myr) clusters, in order to combine them with our ground based medium resolution high S/N VLT/X-shooter spectroscopy (and existing HST U-band and optical imaging), to confirm or refute age spreads within them. We will be able to place limits of >10-to-1, first-to-second generation mass ratios, which will directly test popular globular cluster formation models. ------------------------------------------------------------------------------------ Observations Description ------------------------ This programme will provide UV imaging in the F275W filter with WFC3 of three ongoing/recent galactic mergers, NGC 34, NGC 4038 (the Antennae), and NGC 7252. It is designed to compliment previous WFC3 and ACS imaging of these galaxies in the optical. ------------------------------------------------------------------------------------ 14593( 2) - 18-Jul-2016 15:36:49 - [ 2] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC-34 GALAXY, INTERACTING RA=00H11M8.4000S, J2000 V = 13.52 GALAXY, STARBURST DEC=-12D06'18.30" Reference Frame: Other: SIMBAD Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. ------------------------------------------------------------------------------------------------------------------------------------ 2 NGC-4038 GALAXY, INTERACTING RA=12H01M54.0000S, J2000 V = 11.2 GALAXY, STARBURST DEC=-18D52'40.00" Reference Frame: Other: SIMBAD Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. ------------------------------------------------------------------------------------------------------------------------------------ 3 NGC-7252 GALAXY, INTERACTING RA=22H20M43.9500S, J2000 V = 12.06 GALAXY, STARBURST DEC=-24D40'39.50" Reference Frame: Other: SIMBAD Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. ------------------------------------------------------------------------------------------------------------------------------------ 14593( 2) - 18-Jul-2016 15:36:49 - [ 3] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-UVIS-DITHER-LINE-3PT Pattern_Purpose DITHER Number_Of_Points 3 Point_Spacing 0.135 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 46.84 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 14593( 2) - 18-Jul-2016 15:36:49 - [ 4] Visit: 01 (NGC 34) Visit Requirements: ORIENT 67D TO 71 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 NGC-34 WFC3/UVI ACCUM UVIS-CENT F275W CR-SPLIT=NO, FLASH=8.0 1 869 S PATTERN 1 1 S ER (2607 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 | ------------------------------------------------------------------------------------------------------------------------------------ NGC-34 1 WFC3/UVI ACCUM UVIS-CEN F275W 1 none none none 1 N/A S TER NGC-34 1 WFC3/UVI ACCUM UVIS-CEN F275W 2 none none none 1 N/A S TER NGC-34 1 WFC3/UVI ACCUM UVIS-CEN F275W 3 none none none 1 N/A S TER 14593( 2) - 18-Jul-2016 15:36:49 - [ 5] Visit: 02 (NGC 4038) Visit Requirements: ORIENT 136D TO 140 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 NGC-4038 WFC3/UVI ACCUM UVIS-CENT F275W CR-SPLIT=NO, FLASH=8.0 1 870 S PATTERN 1 1 S ER (2610 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 | ------------------------------------------------------------------------------------------------------------------------------------ NGC-4038 1 WFC3/UVI ACCUM UVIS-CEN F275W 1 none none none 1 N/A S TER NGC-4038 1 WFC3/UVI ACCUM UVIS-CEN F275W 2 none none none 1 N/A S TER NGC-4038 1 WFC3/UVI ACCUM UVIS-CEN F275W 3 none none none 1 N/A S TER 14593( 2) - 18-Jul-2016 15:36:49 - [ 6] Visit: 03 (NGC 7252) Visit Requirements: ORIENT 55D TO 60 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 NGC-7252 WFC3/UVI ACCUM UVIS-CENT F275W CR-SPLIT=NO, FLASH=8.0 1 871 S GS ACQ SCENARIO BASE1B3; S ER (2613 S) PATTERN 1 1 ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ NGC-7252 1 WFC3/UVI ACCUM UVIS-CEN F275W 1 none none none 1 N/A S TER NGC-7252 1 WFC3/UVI ACCUM UVIS-CEN F275W 2 none none none 1 N/A S TER NGC-7252 1 WFC3/UVI ACCUM UVIS-CEN F275W 3 none none none 1 N/A S TER 14593( 2) - 18-Jul-2016 15:36:49 - [ 7] Summary Form for Proposal 14593 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures UVIS-CENTER ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/UVIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO, FLASH=8.0 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements GS ACQ SCENARIO BASE1B3, ORIENT 136D TO 140 D, ORIENT 55D TO 60 D, ORIENT 67D TO 71 D, PATTERN 1 1 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F275W ------------------------------------------------------------------------------------------------------------------------------------ Target Names NGC-34, NGC-4038, NGC-7252 ------------------------------------------------------------------------------------------------------------------------------------