Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 1153c Report Date: 09-May-96:16:14 Version: ********** Check-in Date: ********** 1.Proposal Title: UV INTERSTELLAR EXTINCTION IN THE SMC ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID INTERSTELLAR MEDIUM GTO/HRS Sub Category DUST ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Prof. John B. Hutchings DOMINION ASTROPHYSICAL OBSER CANADA (604)388-3909 PROFESSOR ------------------------------------------------------------------------------------ 7. Abstract IUE spectra have shown that the SMC has high UV extinction compared with the galaxy. Because of this IUE data have not been good enough to define the extinction curve well. This proposal is to obtain good S/N data on reddened and unreddened stars of the same type in the SMC, to obtain better estimate of the UV extinction curve. Parallel WFC exposures in the SMC with the prism will pick out hot stars for further studies and map the UV extinction. ------------------------------------------------------------------------------------ 8. Scientific Key Words: REDDENED BO STARS IN SMC FOR UV EXTINCTION ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 0.50 par: 0 10. Num targs pri: 6 par: 0 ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 1153c PI: Prof. John B. Hutchings Proposal Title: UV INTERSTELLAR EXTINCTION IN THE SMC ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ John B. Hutchings DOMINION ASTROPHYSICAL CANADA OBSERVATORY ------------------------------------------------------------------------------------ 3. Description of proposed observations. All observations with Blue digicon. Each star to be observed with G130H, G190H, G270H gratings; 0.5" aperture to be used for all observations. Parallel observations with the WFC in UV grating mode requested for the duration of the dwell time at each star. ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. ST observations are required to obtain the high S/N data required. IUE is not sensitive enough and has poor S/N. The dispersion chosen will provide sufficient resolution to distinguish line features from continuum variations. ------------------------------------------------------------------------------------ 7. Data reduction and analysis plans. UV flux distributions of three stars will be compared with each other and with appropriate model atmospheres, to derive extinction curves. Stellar line features will also be examined as part of stellar wind studies in the SMC. WFC UV grating data will provide deep investigation of SMC stellar populations, with particular emphasis on reddened early type stars. Appropriate facilities and software exist at DAO for all analysis. ------------------------------------------------------------------------------------ 10. Resources to be supplied by investigator's institution(s). All analysis on spectra can be done at DAO from standard ST product tapes. ------------------------------------------------------------------------------------ 13. FOS spectra will be obtained in the 1200-3000A region of one unreddened and two reddened early B type stars in the SMC. The data will define the UV extinction curves. The reddened stars have very differing degrees of visible diffuse interstellar band absorption. ------------------------------------------------------------------------------------ 11. Address Information Name: JOHN B. HUTCHINGS Category: PI Institution: DOMINION ASTROPHYSICAL OBSERVATOR Address: 5071 W. SAANICH RD. R.R. #5 V8X 4M6 City: VICTORIA State: BC Zip Code: Country: CANADA Telephone: Telex (or e-mail): ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 1153c [ 3] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial |Acqui|FLX| Flux data No | Name | Description | Position |Eqnx | Vel. |Prblm|REF| | | | | | | | | ------------------------------------------------------------------------------------------------------------------------------------ 1 AZZ104 B1 STAR RA=0H 50M 46.2S +/- 1", 1950 1 V=13.13 +/- 0.05 DEC=-72D 56' 6" +/- 1" 2 E(B-V)=0 +/- 0.05 ------------------------------------------------------------------------------------------------------------------------------------ 2 AZZ398 B2 STAR RA=1H 5M 22.2S +/- 1", ^ 1 V=13.85 +/- 0.05 DEC=-72D 4' 0" +/- 1" 2 E(B-V)=0.2 +/- 0.05 ------------------------------------------------------------------------------------------------------------------------------------ 3 AZZ456 BO STAR RA=1H 10M 11.4S +/- 1", ^ 1 V=12.88 +/- 0.05 DEC=-72D 50' 48" +/- 1" 2 E(B-V) = 0.3 +/- 0.05 ------------------------------------------------------------------------------------------------------------------------------------ TARGET LIST c)Generic Targets ID = 1153c [ 4] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 7 ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Selection Criteria |Acqui|FLX| Flux data No | Name | Description | |Prblm|REF| | | | | | | ------------------------------------------------------------------------------------------------------------------------------------ 4 AZZ104-FIELD FIELD IN WFC SMC FIELD IN WFC, FOR PARALLEL OBS ------------------------------------------------------------------------------------------------------------------------------------ 5 AZZ398-FIELD ^ ^ ------------------------------------------------------------------------------------------------------------------------------------ 6 AZZ456-FIELD ^ ^ ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 1153c [ 5] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |10 | 11 | 12 |13 |14| 15 ------------------------------------------------------------------------------------------------------------------------------------ Line | Seq | Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | S/N |Flx|Pr| Special Number | Name | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| |Rel. Time|Ref| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 AZZ104 FOS/BL ACQ/ 4.3 MIRROR BRIGHT=65000 1 5S 1 ONBOARD ACQ FOR 2- BINARY 4 CYCLE 2 /1-15 ------------------------------------------------------------------------------------------------------------------------------------ 2 ^ ^ ACCUM 0.5 G130H 1150- ^ 2M ^ SEQ 2-4 NO GAP 1608 ------------------------------------------------------------------------------------------------------------------------------------ 3 ^ ^ ^ ^ G190H 1595- ^ ^ ^ 2282 ------------------------------------------------------------------------------------------------------------------------------------ 4 ^ ^ ^ ^ G270H 2227- ^ 1M ^ 3306 ------------------------------------------------------------------------------------------------------------------------------------ 5 AZZ104- WFC IMAGE ALL G200L ^ 5M ^ PAR WITH 2 FIELD ------------------------------------------------------------------------------------------------------------------------------------ 6 AZZ398 FOS/BL ACQ/ 4.3 MIRROR BRIGHT=60000 ^ 11S ^ ONBOARD ACQ FOR 7- BINARY 9 ------------------------------------------------------------------------------------------------------------------------------------ 7 ^ ^ ACCUM 0.5 G130H 1150- ^ 3M ^ SEQ 7-9 NO GAP 1608 ------------------------------------------------------------------------------------------------------------------------------------ 8 ^ ^ ^ ^ G190H 1595- ^ ^ ^ 2282 ------------------------------------------------------------------------------------------------------------------------------------ 9 ^ ^ ^ ^ G270H 2227- ^ 2M ^ 3306 ------------------------------------------------------------------------------------------------------------------------------------ 10 AZZ398- WFC IMAGE ALL G200L 1 8M 1 PAR WITH 7 FIELD ------------------------------------------------------------------------------------------------------------------------------------ 11 AZZ456 FOS/BL ACQ/ 4.3 MIRROR BRIGHT=60000 ^ 11S ^ ONBOARD ACQ FOR 12 BINARY -14 ------------------------------------------------------------------------------------------------------------------------------------ 12 AZZ456 FOS/BL ACCUM 0.5 G130H 1150- 1 3M 1 SEQ 12-14 NO GAP 1608 ------------------------------------------------------------------------------------------------------------------------------------ 13 ^ ^ ^ ^ G190H 1595- ^ ^ ^ 2282 ------------------------------------------------------------------------------------------------------------------------------------ 14 ^ ^ ^ ^ G270H 2227- ^ 2M ^ 3306 ------------------------------------------------------------------------------------------------------------------------------------ 15 AZZ456- WFC IMAGE ALL G200L ^ 8M ^ PAR WITH 12 FIELD ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 1153c [ 6] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations FOS/BL ^ WFC ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ/BINARY ACCUM ^ IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters BRIGHT=65000 BRIGHT=60000 ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GTO/HRS ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 0.50 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category INTERSTELLAR MEDIUM ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category DUST ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ONBOARD ACQ FOR 2-4; CYCLE 2 /1-15 SEQ 2-4 NO GAP PAR WITH 2 ONBOARD ACQ FOR 7-9 SEQ 7-9 NO GAP PAR WITH 7 ONBOARD ACQ FOR 12-14 SEQ 12-14 NO GAP PAR WITH 12 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR G130H G190H G270H G200L ------------------------------------------------------------------------------------------------------------------------------------ Target Names AZZ104 AZZ398 AZZ456 AZZ104-FIELD AZZ398-FIELD AZZ456-FIELD ------------------------------------------------------------------------------------------------------------------------------------