! GO6614 Phase II Proposal --- submitted by K. J. Mighell on 9 February 1996 ! ! Hubble Space Telescope Cycle 6 (1996) Phase II Proposal Template ! $Id: 6614,v 6.1 1996/05/15 20:31:03 pepsa Exp $ ! Hubble Space Telescope Cycle 6 (1996) Phase II Proposal Template ! $Id: 6614,v 6.1 1996/05/15 20:31:03 pepsa Exp $ ! ! Refer to the HST Phase II Proposal Instructions to fill this out ! ! Anything after a "!" is ignored, and may be deleted ! ! All keywords with multiple entries are comma delimited except the ! Visit_Requirements and Special_Requirements keywords which can be ! delimited with carriage returns or semi-colons, but not commas ! ! For help call your Program Coordinator: Landis ! Phone: 410-338-4560 , E-mail: landis@stsci.edu ! ! This partially completed template was generated from a Phase I proposal. ! Name of Phase I Proposal: archive-0579.mighell.prop ! Date generated: Fri Dec 22 15:59:07 EST 1995 ! Proposal_Information ! Section 4 Title: The Star Formation History of the Sagittarius Dwarf Spheroidal Galaxy Proposal_Category: GO Scientific_Category: STELLAR POPULATIONS Cycle: 6 Investigators PI_name: Kenneth Mighell PI_Institution: Columbia University CoI_Name: Taft Armandroff CoI_Institution: Kitt Peak National Observatory Contact: N ! Y or N (designate at most one contact) CoI_Name: Ata Sarajedini CoI_Institution: Kitt Peak National Observatory Contact: N ! Y or N (designate at most one contact) CoI_Name: Andrew Layden CoI_Institution: McMaster University Contact: N ! Y or N (designate at most one contact) CoI_Name: Mario Mateo CoI_Institution: University of Michigan Contact: N ! Y or N (designate at most one contact) CoI_Name: Flavio Fusi Pecci CoI_Institution: Universita di Bologna Contact: N ! Y or N (designate at most one contact) CoI_Name: Francesco Ferraro CoI_Institution: Universita di Bologna Contact: N ! Y or N (designate at most one contact) CoI_Name: Roberto Buonanno CoI_Institution: Osservatorio Astronomico di Roma Contact: N ! Y or N (designate at most one contact) Abstract: ! Free format text (please update) We propose WFPC2 observations that will provide deep VI color- magnitude diagrams of the field stellar population of the Sagittarius dwarf spheroidal galaxy which is the nearest galaxy to the Milky Way. We will determine the star formation history of the stellar populations from a) the location and distribution of stars near the main-sequence turnoff, b) the luminosities, colors, and metallicities of stars on the giant branch, c) the relation of horizontal-branch morphology to stellar ages and metallicities, and d) the stellar luminosity function near the main-sequence turnoff. This investigation will provide valuable information on the formation and evolution of dwarf spheroidal galaxies in the Local Group. Questions ! Free format text (please update) Observing_Description: We will observe four fields in the Sagittarius dwarf spheroidal galaxy and two background fields. We will spend two orbits per target field using the WFPC2 instrument with the F555W and F814W filters. We have 6 target fields and will use 12 primary orbits in 6 visits (2 orbits/visit). The first orbit of each visit will have 11 exposures : 6x160s (F555W) and 5x160s (F814W). The second orbit of each visit will have 4 exposures : 2x600s (F555W) and 2x500s (F814W). All exposures will be taken at ATD-GAIN=15 (high-gain) with CLOCKS=NO and CR-SPLIT=NO. The target SGR-DSPH1 is 12 arcmin north of the Sgr globular cluster M54 and was observed by Sarajedini & Layden (1995, AJ, 109, 1086). The target SGR-DSPH2 is 2 arcmin north of SGR-DSPH1. This will allow a 2 to 13 percent overlap depending on the orientation of the HST. The target SGR-DSPH3 is in the center of the field observed by Mateo et al. (1995, AJ, 109, 588). The target SGR-DSPH4 is 2 arcmin north of SGR-DSPH3. The target SGR-MWG1 is in the center of the Mateo \et (1995) control field. The target SGR-MWG2 is two arcmin north of SGR-MWG1. The small amount of field overlap will allow us to measure measure many stars at two different locations within the WFPC2 instrument. This will allow us to determine the self-consistency of the WFPC2 photometry. Each 160-sec exposure pair of F555W and F814W will allow us to construct VI color-magnitude diagrams from ~1.3 mag above the horizontal branch (V_HB ~ 18.3 mag) to ~2.7 mag below an old 15 Gyr main-sequence turnoff (V_TO ~ 21.8 mag) assuming a minimum detection of signal-to-noise ratio S/N=5. All our S/N calculations assume a background level of V=20.0 mag/arcsec^2. Combining the photometry from three 160-sec exposure pairs together will allow us reach a limiting magnitude (S/N=5) of 24.7<=V<=25.4 mag (depending on the areal stellar density) which is at least 2.9 mag below the main-sequence turnoff of an old 15 Gyr stellar population. The final composite VI color-magnitude diagram will have a dynamic range of over 8 magnitudes from about 1.3 mag above the horizontal branch to at least 4 magnitudes (conservatively) below the main-sequence turnoff of the oldest stellar population in the Sgr dwarf spheroidal galaxy. Real_Time_Justification: None. The supporting ground-based VI CCD observations already exist within our group. Calibration_Justification: ! Move appropriate text from Real_Time_Justification Additional_Comments: Fixed_Targets Target_Number: 1 Target_Name: SGR-DSPH1 Alternate_Names: Description: GALAXY, DWARF SPHEROIDAL Position: RA=18H 55M 03.30S +/- 0.01S, DEC=-30D 16' 42.0" +/- 0.1" Equinox: J2000 RV_or_Z: RA_PM: 0.0 Dec_PM: 0.0 Epoch: Annual_Parallax: Flux: V=17 B-V=0.6 Comments: DO NOT USE THE GLOBULAR CLUSTER M54 AS A GUIDE STAR. ! THIS FIELD IS 12 ARCMIN NORTH OF THE GLOBULAR CLUSTER M54. ! SARAJEDINI & LAYDEN (1995, AJ, 109, 1086) OBSERVED THIS SGR DSPH FIELD. Target_Number: 2 Target_Name: SGR-DSPH2 Alternate_Names: Description: GALAXY, DWARF SPHEROIDAL Position: RA=18H 55M 03.30S +/- 0.01S, DEC=-30D 14' 42.0" +/- 0.1" Equinox: J2000 RV_or_Z: RA_PM: 0.0 Dec_PM: 0.0 Epoch: Annual_Parallax: Flux: V=17 B-V=0.6 Comments: DO NOT USE THE GLOBULAR CLUSTER M54 AS A GUIDE STAR. ! THIS FIELD IS 14 ARCMIN NORTH OF THE GLOBULAR CLUSTER M54. ! SARAJEDINI & LAYDEN (1995, AJ, 109, 1086) OBSERVED THIS SGR DSPH FIELD. Target_Number: 3 Target_Name: SGR-DSPH3 Alternate_Names: Description: GALAXY, DWARF SPHEROIDAL Position: RA=19H 06M 11.00S +/- 0.01S, DEC=-30D 25' 22.0" +/- 0.1" Equinox: J2000 RV_or_Z: RA_PM: 0.0 Dec_PM: 0.0 Epoch: Annual_Parallax: Flux: V=17 B-V=0.6 Comments: ! MATEO ET AL. (1995, AJ, 109, 588) OBSERVED THIS SGR DSPH FIELD. Target_Number: 4 Target_Name: SGR-DSPH4 Alternate_Names: Description: GALAXY, DWARF SPHEROIDAL Position: RA=19H 06M 11.00S +/- 0.01S, DEC=-30D 23' 22.0" +/- 0.1" Equinox: J2000 RV_or_Z: RA_PM: 0.0 Dec_PM: 0.0 Epoch: Annual_Parallax: Flux: V=17 B-V=0.6 Comments: ! MATEO ET AL. (1995, AJ, 109, 588) OBSERVED THIS SGR DSPH FIELD. Target_Number: 5 Target_Name: SGR-MWG1 Alternate_Names: Description: GALAXY, SPIRAL Position: RA=18H 33M 26.00S +/- 0.01S, DEC=-40D 57' 57.0" +/- 0.1" Equinox: J2000 RV_or_Z: RA_PM: 0.0 Dec_PM: 0.0 Epoch: Annual_Parallax: Flux: V=17 B-V=0.6 Comments: ! MATEO ET AL. (1995, AJ, 109, 588) OBSERVED THIS MWG BACKGROUND FIELD. Target_Number: 6 Target_Name: SGR-MWG2 Alternate_Names: Description: GALAXY, SPIRAL Position: RA=18H 33M 26.00S +/- 0.01S, DEC=-40D 55' 57.0" +/- 0.1" Equinox: J2000 RV_or_Z: RA_PM: 0.0 Dec_PM: 0.0 Epoch: Annual_Parallax: Flux: V=17 B-V=0.6 Comments: ! MATEO ET AL. (1995, AJ, 109, 588) OBSERVED THIS MWG BACKGROUND FIELD. Solar_System_Targets ! Section 5.2 Generic_Targets ! Section 5.3 Scan_Data ! Appendix B ! This is a template for a single visit containing a single exposure ! Repeat exposure and visit blocks as needed Visits Visit_Number: 01 Visit_Requirements: On_Hold_Comments: Visit_Comments: Exposure_Number: 11 Target_Name: SGR-DSPH1 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 6 Time_Per_Exposure: 160S Special_Requirements: Exposure_Number: 17 Target_Name: SGR-DSPH1 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 5 Time_Per_Exposure: 160S Special_Requirements: Exposure_Number: 21 Target_Name: SGR-DSPH1 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 2 Time_Per_Exposure: 600S Special_Requirements: Exposure_Number: 23 Target_Name: SGR-DSPH1 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 2 Time_Per_Exposure: 500S Special_Requirements: Visit_Number: 02 Visit_Requirements: On_Hold_Comments: Visit_Comments: Exposure_Number: 11 Target_Name: SGR-DSPH2 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 6 Time_Per_Exposure: 160S Special_Requirements: Exposure_Number: 17 Target_Name: SGR-DSPH2 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 5 Time_Per_Exposure: 160S Special_Requirements: Exposure_Number: 21 Target_Name: SGR-DSPH2 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 2 Time_Per_Exposure: 600S Special_Requirements: Exposure_Number: 23 Target_Name: SGR-DSPH2 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 2 Time_Per_Exposure: 500S Special_Requirements: Visit_Number: 03 Visit_Requirements: On_Hold_Comments: Visit_Comments: Exposure_Number: 11 Target_Name: SGR-DSPH3 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 6 Time_Per_Exposure: 160S Special_Requirements: Exposure_Number: 17 Target_Name: SGR-DSPH3 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 5 Time_Per_Exposure: 160S Special_Requirements: Exposure_Number: 21 Target_Name: SGR-DSPH3 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 2 Time_Per_Exposure: 600S Special_Requirements: Exposure_Number: 23 Target_Name: SGR-DSPH3 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 2 Time_Per_Exposure: 500S Special_Requirements: Visit_Number: 04 Visit_Requirements: On_Hold_Comments: Visit_Comments: Exposure_Number: 11 Target_Name: SGR-DSPH4 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 6 Time_Per_Exposure: 160S Special_Requirements: Exposure_Number: 17 Target_Name: SGR-DSPH4 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 5 Time_Per_Exposure: 160S Special_Requirements: Exposure_Number: 21 Target_Name: SGR-DSPH4 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 2 Time_Per_Exposure: 600S Special_Requirements: Exposure_Number: 23 Target_Name: SGR-DSPH4 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 2 Time_Per_Exposure: 500S Special_Requirements: Visit_Number: 05 Visit_Requirements: On_Hold_Comments: Visit_Comments: Exposure_Number: 11 Target_Name: SGR-MWG1 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 6 Time_Per_Exposure: 160S Special_Requirements: Exposure_Number: 17 Target_Name: SGR-MWG1 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 5 Time_Per_Exposure: 160S Special_Requirements: Exposure_Number: 21 Target_Name: SGR-MWG1 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 2 Time_Per_Exposure: 600S Special_Requirements: Exposure_Number: 23 Target_Name: SGR-MWG1 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 2 Time_Per_Exposure: 500S Special_Requirements: Visit_Number: 06 Visit_Requirements: On_Hold_Comments: Visit_Comments: Exposure_Number: 11 Target_Name: SGR-MWG2 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 6 Time_Per_Exposure: 160S Special_Requirements: Exposure_Number: 17 Target_Name: SGR-MWG2 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 5 Time_Per_Exposure: 160S Special_Requirements: Exposure_Number: 21 Target_Name: SGR-MWG2 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 2 Time_Per_Exposure: 600S Special_Requirements: Exposure_Number: 23 Target_Name: SGR-MWG2 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: CLOCKS=NO,ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 2 Time_Per_Exposure: 500S Special_Requirements: ! Comments: Data_Distribution ! Defaults indicated; change if desired Medium: 8MM ! 8MM or 6250BPI or 1600BPI Blocking_Factor: 10 ! 10 or 1 ! Only astronomers with very old 9- ! track tape drives should consider ! a blocking factor of 1 Ship_To: PI_Address ! STSCI or PI_Address or ! PI Address from Phase I is: ! ! Department of Astronomy ! 538 West 120th Street ! New York ! 10027 ! ! Ship_Via: UPS ! UPS (2-day) or OVERNIGHT ! Overnight shipping done at PI expense Recipient_Email: ! mighell@figaro.phys.columbia.edu ! Needed if Ship_To: is not PI_Address ! ! Let us know what you think of this template and software! ! Please send a list of your likes and dislikes to your Program Coordinator