12609( 2) - 08-Jul-2011 18:05:17 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 12609 Version: 2 Check-in Time: 08-Jul-2011 18:05:17 STScI Edit Number: 0 Title Imaging the Distribution of Iron in SN 1885 in M31 ------------------------------------------------------------------------------------ Type Cycle GO 19 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Robert A. Fesen Dartmouth College CoI: Dr. Andrew J. S. Hamilton University of Colorado at Boulder N CoI: Dr. Peter A. Hoeflich Florida State University N ------------------------------------------------------------------------------------ Abstract Type Ia supernovae are the thermonuclear explosions of CO white dwarfs but we don't know the specifics of how the nuclear burning proceeds from the core outward once it starts. The thermonuclear instability is thought to start off as a subsonic turbulent deflagration wave but then transition into a supersonic detonation wave. While Ni-56 mass differences between normal and subluminous Type Ia SNe reflect differences in the amount of burning that has occurred, we don't know if the explosion begins at the very center or off-center as some recent models suggest. Directly imaging the chemical distribution of ejecta from a Type Ia SN is actually possible in the case of the subluminous Type Ia SN 1885 which occurred on the near-side of M31's central bulge. The entire 126 year old remnant -- from core to the outer edge -- is visible via strong Ca and Fe line absorptions. In Cycle 17, we imaged the remnant in Fe I using ACS/WFC which revealed a strongly off-center Fe I distribution. However, the dominant ionization species of the remnant's iron-rich ejecta is Fe II, not Fe I. Here we propose a WFC3/F225W Fe II image of SN 1885 to obtain a high-resolution 2D map of all its iron-rich ejecta by taking advantage of an extraordinary situation: Having a young, nearby Type Ia SN remnant visible in silhouette against a galaxy-size light table -- plus a NUV WFC3 filter (F225W) that isolates the strong resonance lines of Fe II. The proposed observation will reveal the remnant's total iron distribution and sphericity as a function of expansion velocity directly testing SN Ia models with a 2D ejecta mapping. ------------------------------------------------------------------------------------ Observations Description ------------------------ This project to to image the remnant of Supernova 1885 which occurred in the bulge of the M31 galaxy using WFC3 and UV filters F225W and F336W to detect the remnant's iron rich ejecta via strong [Fe II] absorptions at 2344 - 2599 Angstroms. An off-band image showing the background light variations will be obtained from a one orbit image taken using the F336W filter. Real Time Justification ----------------------- 12609( 2) - 08-Jul-2011 18:05:17 - [ 2] Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 12609( 2) - 08-Jul-2011 18:05:17 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC224-SN188 ISM, ABSORPTION LINE RA=00H42M42.9600S +/- 0.1", J2000 V = 10.0 5 SYSTEM, EJECTA, SNR DEC=+41D16'5.00" +/- 0.1" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 12609( 2) - 08-Jul-2011 18:05:17 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-UVIS-MOSAIC-LINE WFC3-UVIS-DITHER-BOX Pattern_Purpose DITHER DITHER Number_Of_Points 3 4 Point_Spacing 3.264 0.173 Line_Spacing 0.112 Coordinate_Frame POS-TARG POS-TARG Pattern_Orient 63.697 23.884 Angle_Between_Sides 81.785 Center_Pattern NO NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-UVIS-DITHER-BOX Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.173 Line_Spacing 0.112 Coordinate_Frame POS-TARG Pattern_Orient 23.884 Angle_Between_Sides 81.785 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 12609( 2) - 08-Jul-2011 18:05:17 - [ 5] Visit: 01 Visit Requirements: 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| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC224-SN18 WFC3/UVI ACCUM UVIS2 F225W 1 650 S PATTERN 1 1 85 S see below ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 1 1 none none 1 654.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 1 2 none none 1 654.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 1 3 none none 1 654.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 1 4 none none 1 654.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 2 1 none none 2 681.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 2 2 none none 2 681.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 2 3 none none 2 681.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 2 4 none none 2 681.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 3 1 none none 3 681.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 3 2 none none 3 681.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 3 3 none none 3 681.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 3 4 none none 3 681.0 S S 12609( 2) - 08-Jul-2011 18:05:17 - [ 6] Visit: 02 Visit Requirements: 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| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC224-SN18 WFC3/UVI ACCUM UVIS2 F225W 1 650 S PATTERN 1 1 85 S see below ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 1 1 none none 1 654.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 1 2 none none 1 654.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 1 3 none none 1 654.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 1 4 none none 1 654.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 2 1 none none 2 681. S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 2 2 none none 2 681 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 2 3 none none 2 681 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 2 4 none none 2 681 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 3 1 none none 3 681.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 3 2 none none 3 681.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 3 3 none none 3 681.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 3 4 none none 3 681.0 S S 12609( 2) - 08-Jul-2011 18:05:17 - [ 7] Visit: 03 Visit Requirements: 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| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC224-SN18 WFC3/UVI ACCUM UVIS2 F225W 1 650 S PATTERN 1 1 85 S see below ------------------------------------------------------------------------------------------------------------------------------------ 2 NGC224-SN18 WFC3/UVI ACCUM UVIS2 F336W 1 681 S PATTERN 2 2 85 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 | ------------------------------------------------------------------------------------------------------------------------------------ NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 1 1 none none 1 654.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 1 2 none none 1 654.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 1 3 none none 1 654.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 1 4 none none 1 654.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 2 1 none none 2 681. S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 2 2 none none 2 681 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 2 3 none none 2 681 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 2 4 none none 2 681 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 3 1 none none 3 681.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 3 2 none none 3 681.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 3 3 none none 3 681.0 S S NGC224-SN1885 1 WFC3/UVI ACCUM UVIS2 F225W 3 4 none none 3 681.0 S S NGC224-SN1885 2 WFC3/UVI ACCUM UVIS2 F336W 1 none none none 4 N/A S NGC224-SN1885 2 WFC3/UVI ACCUM UVIS2 F336W 2 none none none 4 N/A S NGC224-SN1885 2 WFC3/UVI ACCUM UVIS2 F336W 3 none none none 4 N/A S 12609( 2) - 08-Jul-2011 18:05:17 - [ 8] 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 | ------------------------------------------------------------------------------------------------------------------------------------ NGC224-SN1885 2 WFC3/UVI ACCUM UVIS2 F336W 4 none none none 4 N/A S 12609( 2) - 08-Jul-2011 18:05:17 - [ 9] Summary Form for Proposal 12609 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures UVIS2 ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/UVIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PATTERN 1 1, PATTERN 2 2 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F225W, F336W ------------------------------------------------------------------------------------------------------------------------------------ Target Names NGC224-SN1885 ------------------------------------------------------------------------------------------------------------------------------------