6708( 5) - 03/01/96 09:51 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 6708 Version: 5 Check-in Date: 01-Mar-1996 09:45:12 1.Proposal Title: Multiwavelength Imaging of two Luminous Blue Compact Galaxies ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle STELLAR POPULATIONS GO 6 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: Goeran Oestlin Astronomiska observatoriet CoI: Nils Bergvall Astronomiska observatoriet, Uppsala N CoI: Ana Hidalgo Astronomiska observatoriet, Uppsala N CoI: Kjell Olofsson Astronomiska observatoriet, Uppsala N CoI: Jari Roennback ESO N ------------------------------------------------------------------------------------ 6. Abstract Blue compact galaxies may hold key information about the early evolution of galaxies and their chemical evolution. Some BCGs are considered as the most interesting young galaxy candidates. Their starburst properties, low dust content and small sizes make them ideal for studying massive stellar evolution and chemical enrichment as well as early galaxy evolution. The relationship with normal dwarf galaxies may be fundamental. Still, their evolutionary history is not very well known. We propose to obtain images in the F218W, F336W, F439W, F555W and F814W filters of the BCG ESO338- IG04. Thereby we will adress the following qestions: What is the distribution and the optical depth of dust in the galaxy? What is the upper mass limit of star formation (SF) in these systems? What is the SF time-scale/size and ages of individual starburst regions? There are indications of recently formed globular clusters in ESO338-IG04, which will be investigated with the help of the images. Alltogether this would help us to draw conclusion on the ages and SF histories as well as on the formation of these galaxies. (The title may seem confusing but at the phase1 stage another galaxy was also included). ------------------------------------------------------------------------------------ 6708( 5) - 03/01/96 09:51 - [ 2] Observations Description ------------------------ We propose to observe the Blue Compact Galaxy ESO338-IG04 in five wavelength bands. When estimating integration times the WFPC2 the simulator on WWW was used. Assuming a mean surface brightness for ESO338-IG04 of 19.5 magnitudes/arcsec^2 in B and using fluxes from IUE-data we get the following integration times and signal to noise ratios: F218W 1800 seconds give S/N = ~ 2 per planetary camera (PC) pixel, in F336W t=900s gives S/N = ~ 4 per PC pixel, in F439W t=800s gives S/N = 4 per PC pixel, in F555W t=260s gives S/N = 6 per PC pixel and in F814W t=520s gives S/N = 7 per PC pixel. Since the estimated V brightnes for the globular cluster candidates are around 21 magnitudes and their sizes less than 0.2 arcsec (tvice half-light radius) they have high surface brightnes and can be detected with high (more than 15) S/N per PC pixel. The observations for each filter will be separated in two exposures to allow for cosmic ray removals. Real Time Justification ----------------------- None. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Media: 8MM Blocking Factor: 10 Ship To: PI_Address Ship Via: Email: , ------------------------------------------------------------------------------------ 6708( 5) - 03/01/96 09:51 - [ 3] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 ESO338-IG04 GALAXY, DWARF COMPACT, RA=19H 27M 57.7S +/- 0.2S, DEC=- J2000 V = 2829 V = 13.5 STARBURST, EXT-CLUSTER, 41D 34' 33.5" +/- 0.5", PLATE- B-V = 0.24 GLOBULAR CLUSTER, ID=01IA U-B = -0.44 V-R = 0.17 6708( 5) - 03/01/96 09:51 - [ 4] Visit: 01 Visit Requirements: ORIENT 250D TO 250D On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 ESO338-IG04 WFPC2 IMAGE PC1-FIX F439W 1 400S ------------------------------------------------------------------------------------------------------------------------------------ 2 ESO338-IG04 WFPC2 IMAGE PC1-FIX F439W 1 400S ------------------------------------------------------------------------------------------------------------------------------------ 3 ESO338-IG04 WFPC2 IMAGE PC1-FIX F336W 1 500S ------------------------------------------------------------------------------------------------------------------------------------ 4 ESO338-IG04 WFPC2 IMAGE PC1-FIX F336W 1 400S ------------------------------------------------------------------------------------------------------------------------------------ 5 ESO338-IG04 WFPC2 IMAGE PC1-FIX F555W 1 100S ------------------------------------------------------------------------------------------------------------------------------------ 6 ESO338-IG04 WFPC2 IMAGE PC1-FIX F555W 1 160S ------------------------------------------------------------------------------------------------------------------------------------ 7 ESO338-IG04 WFPC2 IMAGE PC1-FIX F218W CR-SPLIT=NO 1 1000S ------------------------------------------------------------------------------------------------------------------------------------ 8 ESO338-IG04 WFPC2 IMAGE PC1-FIX F218W CR-SPLIT=NO 1 800S ------------------------------------------------------------------------------------------------------------------------------------ 9 ESO338-IG04 WFPC2 IMAGE PC1-FIX F814W 1 260S ------------------------------------------------------------------------------------------------------------------------------------ 10 ESO338-IG04 WFPC2 IMAGE PC1-FIX F814W 1 260S ------------------------------------------------------------------------------------------------------------------------------------ 6708( 5) - 03/01/96 09:51 - [ 5] Summary Form for Proposal 6708 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category STELLAR POPULATIONS ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 250D TO 250D ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F439W F336W F555W F218W F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names ESO338-IG04 ------------------------------------------------------------------------------------------------------------------------------------