6492( 5) - 03/17/97 11:17 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 6492 Version: 5 Check-in Date: 17-Mar-1997 10:36:43 1.Proposal Title: High Resolution Imaging of the Massive Overcontact Binary RY Scuti ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle BINARIES AND STAR FOR GO 6 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: ROBERT D. GEHRZ UNIVERSITY OF MINNESOTA CoI: Terry Jones University of Minnesota Y CoI: Roberta Humphreys University of Minnesota N CoI: Kris Davidson University of Minnesota N CoI: Joachim Krautter University of Heidelberg N ------------------------------------------------------------------------------------ 6. Abstract RY Scuti is a post-main sequence, eclipsing, 'overcontact' binary. The two components are very massive, 49 and 39 M_\odot , with a combined luminosity in excess of 3* 10^6L_\odot . Ground based observations have established that this star is surrounded with a very unusual nebula about 1 arcsecond in extent containing both ionized gas and thermally emitting dust. The Ne abundance in the nebula is well above solar composition, indicating the system is at a critical phase of its evolution. We propose to image the nebulosity around RY Scuti to investigate its morphology and the mass loss process in the system. We will use these images to distinguish between hypothesized mass loss scenarios and to study the interface between the plasma and dust regions of the nebula. ------------------------------------------------------------------------------------ 6492( 5) - 03/17/97 11:17 - [ 2] Observations Description ------------------------ RY Scuti is a relatively bright object (V = 9.1, B = 10.1) surrounded by faint nebulosity. We have planned a series of exposures in V (F547M), B (F467M) and HAlpha (F656N) with the shortest chosen to avoid bleeding from the central star and the longest to image the fainter outer parts of the nebula. The exposure times are: 0.5s, 3s, 20s, 60s in V; 10s, 50s, 250s in B; 15s, 75s, 400s in HAlpha . With standard allowances for acquisition and overhead time this fills one orbit. begintabularlll Cycle 6 & Primary Orbits:1 & Exposures:10, endtabular Real Time Justification ----------------------- None. R. D. Gehrz and J. Krautter will be obtaining supporting ground-based near-IR imaging observations using IRAC-2 on the 2.3-m telescope and mid-IR imaging observations using the TIMMI camera on the 3.6-m telescope at ESO. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Media: 8MM Blocking Factor: 10 Ship To: PI_Address Ship Via: UPS Email: ------------------------------------------------------------------------------------ 6492( 5) - 03/17/97 11:17 - [ 3] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 100 HD169515 STAR,SUPERGIANT RA=18H 22M 42.706S +/- 1950 V = 9.1+/-0.1 O,INTERACTING BINARY 0.0011S,DEC=-12D 43' 9.24" +/- B-V = 1.06+/-0.05 0.005" E(B-V) = 1.37+/-0.1 6492( 5) - 03/17/97 11:17 - [ 4] Visit: 01 Visit Requirements: 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 HD169515 WFPC2 IMAGE PC1 F467M ATD-GAIN=15 1 2 S SEQ 101-303 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 102 HD169515 WFPC2 IMAGE PC1 F467M DITHER-TYPE=LINE, 2 100 S DITHER-LINE-SPACING=0.161 ------------------------------------------------------------------------------------------------------------------------------------ 301 HD169515 WFPC2 IMAGE PC1 F656N ATD-GAIN=15 1 5 S ------------------------------------------------------------------------------------------------------------------------------------ 302 HD169515 WFPC2 IMAGE PC1 F656N 2 20 S ------------------------------------------------------------------------------------------------------------------------------------ 303 HD169515 WFPC2 IMAGE PC1 F656N DITHER-TYPE=LINE, 1 120 S DITHER-LINE-SPACING=0.161 ------------------------------------------------------------------------------------------------------------------------------------ 6492( 5) - 03/17/97 11:17 - [ 5] Summary Form for Proposal 6492 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters ATD-GAIN=15 DITHER-LINE-SPACING=0.161 DITHER-TYPE=LINE ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category BINARIES AND STAR FORMATION ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements SEQ 101-303 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F467M F656N ------------------------------------------------------------------------------------------------------------------------------------ Target Names HD169515 ------------------------------------------------------------------------------------------------------------------------------------