6540( 5) - 08/21/97 14:05 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 6540 Version: 5 Check-in Date: 21-Aug-1997 14:04:34 1.Proposal Title: Imaging Circumstellar Nebulae around Luminous Blue Variables in the Magellanic Clouds ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle HOT STARS GO 6 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: Regina E. Schulte-Ladbeck UNIVERSITY OF PITTSBURGH CoI: Antonella Nota Space Telescope Science Institute N CoI: Mark Clampin Space Telescope Science Institute N CoI: Mario Livio Space Telescope Science Institute N CoI: Claus Leitherer Space Telescope Science Institute N CoI: Anna Pasquali Space Telescope Science Institute N ------------------------------------------------------------------------------------ 6. Abstract We propose to exploit the unique spatial resolution of the Planetary Camera to image circumstellar ejecta of hot and luminous stars in the Magellanic Clouds (MCs), where ground- based imaging of new, spectroscopically discovered nebulae is difficult and cannot provide meaningful spatial information. The objectives are to study the distribution of the ionized gas and dust in order to determine the morphology and physical properties of the circumstellar nebulae, by observing them in a narrow, line-free V continuum filter and in the HAlpha emission line. These data will provide information about the mass-loss history of the central stars, important for understanding the evolution of massive stars and of the interstellar medium of their host galaxies. Two aspects of this proposal are of particular significance: the study of the nebular morphology, to provide input to hydrodynamic models now becoming available, and the determination of the total mass ejected, which can now be predicted with the latest theoretical models of massive-star evolution. This promises to supply us with a much better knowledge of the statistical properties of LBV nebulae, which is needed to test evolutionary models. There is a larger number of LBVs and candidates known in the MCs than in the Galaxy, and only HST is capable to provide sufficent spatial resolution to study them. ------------------------------------------------------------------------------------ 6540( 5) - 08/21/97 14:05 - [ 2] Observations Description ------------------------ We propose to use the WFPC2 Planetary Camera to obtain high spatial resolution images of a number of LBVs and candidates in the MCs, with the primary objective of characterizing the observational properties of their circumstellar shells. The Planetary Camera is the ideal instrument for this investigation, for three reasons: beginitemize em high angular resolution (0.046"/pixel) of the Point Spread Function, combined with a relatively large field of view (35"*35"); em good spectral response at the wavelengths of interest; em suitability of the CCD cameras for observations requiring high dynamic range, as WFPC2 CCDs have MPP architecture (see WFPC2 Handbook, 1995), and, therefore, limited blooming on saturated stars. enditemizeFor each object of the sample, we propose to take PC images in the following filters: 547M - V Continuum, and F658N - HAlpha. Our observational strategy will be to obtain two images of each object/filter combination, to properly correct for cosmic rays. The exposure time for each of the two images has been calculated in order to achieve a S/N of 10 in the nebular region, while saturating the central object. On the basis of the WWW WFPC2 exposure time estimator and the WFPC2 handbook, using the PC camera and the F547M filter for a star with V = 11 and surface brightness in the nebula of ~eq 18 magnitudes/square arcsecs, two exposures of 300 secs, for each filter, will achieve a S/N per pixel of 10. For the H Alpha emission, assuming a typical line flux of 6times10^-14 ergs/sec/cm^2/arcsec^2, we derive a S/N per pixel of 10 for two 500 sec exposures. The stars themselves will saturate columns contained within a radius of approximately 0.3 arcsecs. For all exposures we will operate the CCDs with the serial clocks running in order to remove excess charge from saturated columns and prevent charge spreading to adjacent columns. This strategy has already proven successful, allowing us to obtain excellent images of AG Carinae (Proposal 5149). Including the Guide Star Acquisitions and the exposure overheads, the complete set of observations for each target requires 45 minutes, half a CVZ orbit. All of the targets are in the CVZ and are physically close together, so that we can make very efficient use of the allocated time, by observing two of the LMC targets per CVZ orbit. The total time required amounts to 6 CVZ orbits. All of the observations will be taken in CVZ. The CVZ orbits will be used to observe multiple targets. Targets have been ordered so to minimise slew time and length. A bug in RPS2 calculates slew times that are incorrect. We have obtained the correct slew times from R. Henry and finetuned the exp. times using these numbers. The current version of the proposal exceeds the TAC allocation of 6 orbits by approximately 22 min, because in the version the slews are still calculated incorrectly. The proposal needs to be rerun after RPS2 has been fixed. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 6540( 5) - 08/21/97 14:05 - [ 3] Data Distribution Media: 8MM Blocking Factor: 10 Ship To: PI_Address Ship Via: UPS Email: ------------------------------------------------------------------------------------ 6540( 5) - 08/21/97 14:05 - [ 4] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 HD35343 EXT-STAR,EMISSION LINE RA=05H 18M 14.84S +/-0.5S, DEC=- J2000 V = 9.97 STAR,LUMINOUS BLUE 69D 15' 00.2" +/-0.5", PLATE- B-V = +0.11 VARIABLE ID=05ZW 2 HD269858 EXT-STAR,EMISSION LINE RA=05H 36M 43.64S +/-0.5S, DEC=- J2000 V = 11.16 STAR,LUMINOUS BLUE 69D 29' 45.9" +/-0.5", PLATE- B-V = -0.07 VARIABLE ID=05ZW 3 S119 EXT-STAR,EMISSION LINE RA=05H 31M 25.97S +/-0.5S, DEC=- J2000 V = 11.90 STAR,LUMINOUS BLUE 69D 05' 37.9" +/-0.5", PLATE- B-V = -0.07 VARIABLE ID=05ZW 4 HD269006 EXT-STAR,EMISSION LINE RA=05H 02M 07.87S +/-0.5S, DEC=- J2000 V = 9.83 STAR,LUMINOUS BLUE 71D 20' 12.8" +/-0.5", PLATE- B-V = +0.19 VARIABLE ID=05ZW 5 HD269582 EXT-STAR,EMISSION LINE RA=05H 27M 53.14S +/-0.5S, DEC=- J2000 V = 11.88 STAR,LUMINOUS BLUE 68D 59' 07.9" +/-0.5", PLATE- B-V = -0.04 VARIABLE ID=05ZW 6 HD269929 EXT-STAR,EMISSION LINE RA=05H 38M 51.91S +/-0.5S, DEC=- J2000 V = 12.20 STAR,LUMINOUS BLUE 69D 08' 07.2" +/-0.5", PLATE- VARIABLE ID=05ZW 7 HD6884 EXT-STAR,EMISSION LINE RA=01H 07M 18.48S +/-0.5S, DEC=- J2000 V = 10.68 STAR,LUMINOUS BLUE 72D 28' 04.3" +/-0.5", PLATE- B-V = +0.08 VARIABLE ID=00RG 8 HD5980 EXT-STAR,LUMINOUS BLUE RA=00H 59M 26.72S +/-0.5S, DEC=- J2000 V = 11.69 VARIABLE 72D 09' 55.4" +/-0.5", PLATE- B-V = -0.20 ID=06B1 9 S61 EXT-STAR,EMISSION LINE RA=05H 45M 52.27S +/-0.5S, DEC=- J2000 V = 12.01 STAR,LUMINOUS BLUE 67D 14' 25.6" +/-0.5", PLATE- B-V = -0.13 VARIABLE ID=06B0 10 HDE269927C EXT-STAR,EMISSION LINE RA=05H 38M 58.50S +/-0.5S, DEC=- J2000 V = 12.48 STAR,LUMINOUS BLUE 69D 29' 20.9" +/-0.5", PLATE- B-V = -0.11 VARIABLE ID=05ZW 11 HD269445 EXT-STAR,EMISSION LINE RA=05H 23M 00.26S +/-0.5S, DEC=- J2000 V = 11.45 STAR,LUMINOUS BLUE 68D 01' 46.8" +/-0.5", PLATE- B-V = +0.27 VARIABLE ID=05ZW 12 BE381 EXT-STAR,EMISSION LINE RA=05H 35M 54.61S +/-0.5S, DEC=- J2000 V = 13.26 STAR,LUMINOUS BLUE 68D 59' 08.4" +/-0.5", PLATE- B-V = +0.04 VARIABLE ID=05ZW 6540( 5) - 08/21/97 14:05 - [ 5] Visit: 01 Visit Requirements: CVZ 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 ------------------------------------------------------------------------------------------------------------------------------------ 101 S61 WFPC2 IMAGE PC1 F547M 1 500 S SEQ 101-102 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 102 S61 WFPC2 IMAGE PC1 F656N CR-SPLIT=0.5 2 1200 S ------------------------------------------------------------------------------------------------------------------------------------ 103 HD269445 WFPC2 IMAGE PC1 F656N 1 800 S ------------------------------------------------------------------------------------------------------------------------------------ 104 HD269582 WFPC2 IMAGE PC1 F656N 1 800 S ------------------------------------------------------------------------------------------------------------------------------------ 105 BE381 WFPC2 IMAGE PC1 F547M 1 500 S SEQ 105-106 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 106 BE381 WFPC2 IMAGE PC1 F656N CR-SPLIT=0.5 2 1200 S ------------------------------------------------------------------------------------------------------------------------------------ 107 HD269929 WFPC2 IMAGE PC1 F656N 1 800 S ------------------------------------------------------------------------------------------------------------------------------------ 6540( 5) - 08/21/97 14:05 - [ 6] Visit: 02 Visit Requirements: CVZ 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 ------------------------------------------------------------------------------------------------------------------------------------ 108 S119 WFPC2 IMAGE PC1 F547M 1 500 S SEQ 108-109 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 109 S119 WFPC2 IMAGE PC1 F656N CR-SPLIT=0.5 2 1200 S ------------------------------------------------------------------------------------------------------------------------------------ 110 HD35343 WFPC2 IMAGE PC1 F656N 1 800 S ------------------------------------------------------------------------------------------------------------------------------------ 111 HDE269927C WFPC2 IMAGE PC1 F656N 1 800 S ------------------------------------------------------------------------------------------------------------------------------------ 112 HD269858 WFPC2 IMAGE PC1 F547M 1 500 S SEQ 112-113 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 113 HD269858 WFPC2 IMAGE PC1 F656N CR-SPLIT=0.5 2 1200 S ------------------------------------------------------------------------------------------------------------------------------------ 114 HD269006 WFPC2 IMAGE PC1 F656N 1 800 S ------------------------------------------------------------------------------------------------------------------------------------ 115 HD5980 WFPC2 IMAGE PC1 F656N 1 800 S ------------------------------------------------------------------------------------------------------------------------------------ 116 HD6884 WFPC2 IMAGE PC1 F656N 1 800 S ------------------------------------------------------------------------------------------------------------------------------------ 6540( 5) - 08/21/97 14:05 - [ 7] Summary Form for Proposal 6540 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=0.5 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category HOT STARS ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements CVZ SEQ 101-102 NON-INT SEQ 105-106 NON-INT SEQ 108-109 NON-INT SEQ 112-113 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F547M F656N ------------------------------------------------------------------------------------------------------------------------------------ Target Names S61 HD269445 HD269582 BE381 HD269929 S119 HD35343 HDE269927C HD269858 HD269006 HD5980 HD6884 ------------------------------------------------------------------------------------------------------------------------------------