11836( 3) - 20-Nov-2008 20:42:10 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 11836 Version: 3 Check-in Time: 20-Nov-2008 20:42:10 STScI Edit Number: 0 Title Chandra Imaging of NGC 922 -- the closest collisional ring galaxy ------------------------------------------------------------------------------------ Type Cycle GO 17 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Andrea H. Prestwich Smithsonian Institution Astrophysical Observatory CoI: Dr. Andreas Zezas Smithsonian Institution Astrophysical N Observatory CoI: Dr. Timothy Paul Roberts University of Durham N CoI: Prof. Martin J. Ward University of Durham N CoI: Mr. Roy Erik Kilgard Wesleyan University N CoI: Dr. Ginevra Trinchieri Osservatorio Astronomico di Brera, Milano N CoI: Dr. Anna Wolter Osservatorio Astronomico di Brera, Milano N CoI: Mr. Ryan Foltz Smithsonian Institution Astrophysical N Observatory ------------------------------------------------------------------------------------ Abstract Ultra Luminous X-ray sources (ULX) have luminosities many times the Eddington limit for a stellar black hole and are associated with massive star formation. This is illustrated by the Chandra image of the Cartwheel, a collisional ring galaxy. The bulk of the X-ray luminosity is produced by 16 ULX co-incident with the outer ring of star formation. We request Chandra and HST time to image another collisional ring galaxy NGC 922. NGC 922 is similar to the Cartwheel, except that it is nearly three times closer and has higher metallicity. We will (1) detect fainter sources than was possible for the Cartwheel, (2) use archival HST data and our new Halpha images to associate X-ray sources with tracers of star formation and (3) study the effect of metallicity on the formation of ULX. ------------------------------------------------------------------------------------ Observations Description ------------------------ This proposal involves H-alpha line and continuum imaging of the nearby collisional ring galaxy NGC 922. The F665N filter is used to image the redshifted H-alpha line and the F621 filter used to image the continuum. We requre at least 5000s in the line filter and 1500s in the continuum. One of our science goals is to determine the positions of bright X-ray sources relative to the H-alpha ring. We therefore opt to use the UVIS-CENTER aperture and a LINE dither to fill in the chip gaps (as well as eliminate hot pixels and cosmic ray hits). Real Time Justification ----------------------- Calibration Justification ------------------------- 11836( 3) - 20-Nov-2008 20:42:10 - [ 2] Additional Comments ------------------- ------------------------------------------------------------------------------------ 11836( 3) - 20-Nov-2008 20:42:10 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC-0922 GALAXY, INTERACTING RA=02H25M4.4000S +/- 0.1", J2000 V = 12.12 GALAXY, RING, SPIRAL, DEC=-24D47'17.00" +/- 0.1" STARBURST Reference Frame: ICRS Comments: This object was generated by the targetselector and retrieved from the NED database. ------------------------------------------------------------------------------------------------------------------------------------ 11836( 3) - 20-Nov-2008 20:42:10 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type LINE WFC3-UVIS-DITHER-LINE Pattern_Purpose DITHER DITHER Number_Of_Points 2 2 Point_Spacing 2.0 0.145 Line_Spacing Coordinate_Frame POS-TARG POS-TARG Pattern_Orient 46.84 46.84 Angle_Between_Sides Center_Pattern NO NO ------------------------------------------------------------------------------------------------------------------------------------ 11836( 3) - 20-Nov-2008 20:42:10 - [ 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 NGC-0922 WFC3/UVI ACCUM UVIS-CENT F665N CR-SPLIT=NO 1 1200 S PATTERN 1 1-2 S ER see below ------------------------------------------------------------------------------------------------------------------------------------ 2 NGC-0922 WFC3/UVI ACCUM UVIS-CENT F621M CR-SPLIT=NO 1 330 S S ER 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 | ------------------------------------------------------------------------------------------------------------------------------------ NGC-0922 1 WFC3/UVI ACCUM UVIS-CEN F665N 1 1 none none 1 2169.0 S S TER NGC-0922 1 WFC3/UVI ACCUM UVIS-CEN F665N 1 2 none none 2 N/A S TER NGC-0922 1 WFC3/UVI ACCUM UVIS-CEN F665N 2 1 none none 2 N/A S TER NGC-0922 1 WFC3/UVI ACCUM UVIS-CEN F665N 2 2 none none 3 2093.0 S S TER NGC-0922 2 WFC3/UVI ACCUM UVIS-CEN F621M 1 1 none none 1 600.0 S S TER NGC-0922 2 WFC3/UVI ACCUM UVIS-CEN F621M 1 2 none none 2 353.0 S S TER NGC-0922 2 WFC3/UVI ACCUM UVIS-CEN F621M 2 1 none none 3 N/A S TER NGC-0922 2 WFC3/UVI ACCUM UVIS-CEN F621M 2 2 none none 3 N/A S TER 11836( 3) - 20-Nov-2008 20:42:10 - [ 6] Summary Form for Proposal 11836 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures UVIS-CENTER ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/UVIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PATTERN 1 1-2 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F621M, F665N ------------------------------------------------------------------------------------------------------------------------------------ Target Names NGC-0922 ------------------------------------------------------------------------------------------------------------------------------------