13644( 5) - 09-Sep-2014 18:19:36 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 13644 Version: 5 Check-in Time: 09-Sep-2014 18:19:36 STScI Edit Number: 3 Title CIII] Emission in z=5.7 Galaxies: A Pathfinder for Galaxy Spectroscopy in the Reionization Era ------------------------------------------------------------------------------------ Type Cycle GO 22 ------------------------------------------------------------------------------------ Investigators Contact? PI: Prof. Xiaohui Fan University of Arizona Y CoI: Prof. Daniel P. Stark University of Arizona N CoI: Dr. Fuyan Bian Australian National University N CoI: Mr. Zheng Cai University of Arizona N CoI: Dr. Linhua Jiang Arizona State University N CoI: Dr. Ian McGreer University of Arizona N CoI: Prof. Brant Robertson University of Arizona N CoI: Prof. Brian Siana University of California - Riverside N ------------------------------------------------------------------------------------ Abstract The last few years has witnessed a rapid increase in the detections of galaxies at z>7, at the end of the reionization era. However, as a result of the increasing attenuation of Ly alpha emission by the partially neutral IGM at this redshift, it is becoming clear that the traditional means of redshift confirmation is bound for limited success; this presents a major challenge to galaxy spectroscopy as we probe deeper into the reionization era with JWST and ELTs. Through our survey of reionization-era analog galaxies at z~2, we find that low metallicity, low luminosity galaxies exhibit strong CIII]1909 nebular emission lines. If, as is expected, CIII] remains strong at high redshift, the line can be used as a powerful alternative to Ly alpha in spectroscopy of reionization-era galaxies. To explore this possibility, we will carry out deep HST WFC3/IR F128N narrow-band imaging of a sample of 8 galaxies at z=5.7 in two fields. At this redshift, the CIII] line is fortuitously located within the F128N passband, allowing detection of CIII] in this sample of spectroscopically confirmed galaxies, reaching a flux limit beyond what is possible with current ground-based observations. Combining the F128N narrow-band imaging with broad-band observations, we will reliably measure the CIII] flux for the brighter objects in our sample (J<~26), and measure or strongly constrain the stacked CIII] flux for fainter objects (J~27). This program will provide the first statistical sample of CIII] emission in galaxies close to the end of reionization. Success in this venture would usher in a new era of redshift confirmation at z>7, guiding the strategy of such programs on future major facilities. ------------------------------------------------------------------------------------ Observations Description ------------------------ we will carry out 6-orbit F128N narrowband imaging for each of our two fields, SDF1324 and SXFDF0217. We will also obtain a 2-orbit F125W broadband imaging of the SXDF0217 field, providing accurate continuum subtraction. For SDF1324, we will rotate the field with a position angle (PA)=102.4 degree to include two high-z galaxies in this field. The coordinates of the two galaxies are (13:24:16.13, +27:44:11.6) and (13:24:13.00, +27:41:45.8), which 13644( 5) - 09-Sep-2014 18:19:36 - [ 2] can be included into one WFC3/IR field with a rotation angle of 102.4 degree. We use the two visits to populate the 6-orbit F128N imaging. In the Visit 01, we use a four-point-dither to populate the first two orbit; and also, we use another four-point-dither to populate the 3rd and 4th orbit. In the Visit 02, we use a four-point-dither to populate the 5th and 6th orbit. For SXDF0217, we will rotate the the field with a PA=49.9 deg to include five high-z galaxies in this field. We will use two visits to populate a 8-orbit for this field. In the Visit 03, we will first obtain a 2-orbit F125W broadband imaging. We use two four-point-dither to populate each orbit of F125W imaging. Then, we obtain 2-orbit F128N narrowband imaging in this visit. We will use a four-point-dither to populate the 2-orbit F128N imaging. In the Visit 04, we carry out a 4-orbit F128N narrowband imaging. We will (1) use a two-point-dither to populate 1-orbit F128N narrowband imaging; (2) a two-point-dither to populate the next orbit of F128N narrowband imaging; (3) a four-point-dither to populate the last 2-orbit of F128N narrowband imaging. ------------------------------------------------------------------------------------ 13644( 5) - 09-Sep-2014 18:19:36 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 SDF1324 GALAXY, HIGH REDSHIFT RA=13H24M16.1280S, J2000 Z = 5.7 J_AB=24-27 GALAXY DEC=+27D44'11.62" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 2 SXDF0217 GALAXY, HIGH REDSHIFT RA=02H17M46.3600S, J2000 J_AB=25-27 GALAXY DEC=-05D27'58.00" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 13644( 5) - 09-Sep-2014 18:19:36 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-IR-DITHER-BOX-MIN Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.572 Line_Spacing 0.365 Coordinate_Frame POS-TARG Pattern_Orient 18.528 Angle_Between_Sides 74.653 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-IR-DITHER-LINE Pattern_Purpose DITHER Number_Of_Points 2 Point_Spacing 0.636 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 41.788 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 13644( 5) - 09-Sep-2014 18:19:36 - [ 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 SDF1324 WFC3/IR MULTIAC IR F128N NSAMP=14, SAMP-SEQ=STEP200 1 DEF GS ACQ SCENARIO SINGLE; CUM (5596.926 PATTERN 1 1 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 SDF1324 WFC3/IR MULTIAC IR F128N NSAMP=15, SAMP-SEQ=SPARS100 1 DEF POS TARG 0.636, 0.0; CUM (5611.747 PATTERN 1 2 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 | ------------------------------------------------------------------------------------------------------------------------------------ SDF1324 1 WFC3/IR MULTIAC IR F128N 1 none none none 1 N/A CUM SDF1324 1 WFC3/IR MULTIAC IR F128N 2 none none none 1 N/A CUM SDF1324 1 WFC3/IR MULTIAC IR F128N 3 none none none 2 N/A CUM SDF1324 1 WFC3/IR MULTIAC IR F128N 4 none none none 2 N/A CUM SDF1324 2 WFC3/IR MULTIAC IR F128N 1 none none none 3 N/A CUM SDF1324 2 WFC3/IR MULTIAC IR F128N 2 none none none 3 N/A CUM SDF1324 2 WFC3/IR MULTIAC IR F128N 3 none none none 4 N/A CUM SDF1324 2 WFC3/IR MULTIAC IR F128N 4 none none none 4 N/A CUM 13644( 5) - 09-Sep-2014 18:19:36 - [ 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 SDF1324 WFC3/IR MULTIAC IR F128N NSAMP=14, SAMP-SEQ=STEP200 1 DEF POS TARG -0.636, 0.0; GS CUM (5596.926 ACQ SCENARIO SINGLE; S) PATTERN 1 1 ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ SDF1324 1 WFC3/IR MULTIAC IR F128N 1 none none none 1 N/A CUM SDF1324 1 WFC3/IR MULTIAC IR F128N 2 none none none 1 N/A CUM SDF1324 1 WFC3/IR MULTIAC IR F128N 3 none none none 2 N/A CUM SDF1324 1 WFC3/IR MULTIAC IR F128N 4 none none none 2 N/A CUM 13644( 5) - 09-Sep-2014 18:19:36 - [ 7] Visit: 03 Visit Requirements: ORIENT 44.8D TO 45.1 D 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 SXDF0217 WFC3/IR MULTIAC IR F125W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF PATTERN 1 1 CUM (2611.753 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 SXDF0217 WFC3/IR MULTIAC IR F125W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF POS TARG 0.636, 0.0; CUM (2611.753 PATTERN 1 2 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 SXDF0217 WFC3/IR MULTIAC IR F128N NSAMP=15, SAMP-SEQ=SPARS100 1 DEF POS TARG 0.0, 0.0; CUM (5611.747 PATTERN 1 3 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 | ------------------------------------------------------------------------------------------------------------------------------------ SXDF0217 1 WFC3/IR MULTIAC IR F125W 1 none none none 1 N/A CUM SXDF0217 1 WFC3/IR MULTIAC IR F125W 2 none none none 1 N/A CUM SXDF0217 1 WFC3/IR MULTIAC IR F125W 3 none none none 1 N/A CUM SXDF0217 1 WFC3/IR MULTIAC IR F125W 4 none none none 1 N/A CUM SXDF0217 2 WFC3/IR MULTIAC IR F125W 1 none none none 2 N/A CUM SXDF0217 2 WFC3/IR MULTIAC IR F125W 2 none none none 2 N/A CUM SXDF0217 2 WFC3/IR MULTIAC IR F125W 3 none none none 2 N/A CUM SXDF0217 2 WFC3/IR MULTIAC IR F125W 4 none none none 2 N/A CUM SXDF0217 3 WFC3/IR MULTIAC IR F128N 1 none none none 3 N/A CUM SXDF0217 3 WFC3/IR MULTIAC IR F128N 2 none none none 3 N/A CUM SXDF0217 3 WFC3/IR MULTIAC IR F128N 3 none none none 4 N/A CUM SXDF0217 3 WFC3/IR MULTIAC IR F128N 4 none none none 4 N/A CUM 13644( 5) - 09-Sep-2014 18:19:36 - [ 8] Visit: 04 Visit Requirements: ORIENT 44.8D TO 45.1 D 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 SXDF0217 WFC3/IR MULTIAC IR F128N SAMP-SEQ=SPARS100, NSAMP=14 1 DEF POS TARG 0.636, 0.0; CUM (2605.873 PATTERN 2 1 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 SXDF0217 WFC3/IR MULTIAC IR F128N NSAMP=15, SAMP-SEQ=SPARS100 1 DEF POS TARG -0.636, 0.0; CUM (2805.874 PATTERN 2 2 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 SXDF0217 WFC3/IR MULTIAC IR F128N NSAMP=15, SAMP-SEQ=SPARS100 1 DEF POS TARG 0.0, 0.0; CUM (5611.747 PATTERN 1 3 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 | ------------------------------------------------------------------------------------------------------------------------------------ SXDF0217 1 WFC3/IR MULTIAC IR F128N 1 none none none 1 N/A CUM SXDF0217 1 WFC3/IR MULTIAC IR F128N 2 none none none 1 N/A CUM SXDF0217 2 WFC3/IR MULTIAC IR F128N 1 none none none 2 N/A CUM SXDF0217 2 WFC3/IR MULTIAC IR F128N 2 none none none 2 N/A CUM SXDF0217 3 WFC3/IR MULTIAC IR F128N 1 none none none 3 N/A CUM SXDF0217 3 WFC3/IR MULTIAC IR F128N 2 none none none 3 N/A CUM SXDF0217 3 WFC3/IR MULTIAC IR F128N 3 none none none 4 N/A CUM SXDF0217 3 WFC3/IR MULTIAC IR F128N 4 none none none 4 N/A CUM 13644( 5) - 09-Sep-2014 18:19:36 - [ 9] Summary Form for Proposal 13644 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/IR ------------------------------------------------------------------------------------------------------------------------------------ Opmodes MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NSAMP=14, NSAMP=15, SAMP-SEQ=SPARS100, SAMP-SEQ=SPARS50, SAMP-SEQ=STEP200 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements GS ACQ SCENARIO SINGLE, ORIENT 44.8D TO 45.1 D, PATTERN 1 1, PATTERN 1 2, PATTERN 1 3, PATTERN 2 1, PATTERN 2 2, POS TARG -0.636, 0.0, POS TARG 0.0, 0.0, POS TARG 0.636, 0.0 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F125W, F128N ------------------------------------------------------------------------------------------------------------------------------------ Target Names SDF1324, SXDF0217 ------------------------------------------------------------------------------------------------------------------------------------