! revised abstract & description of observations---rtr 13March ! Hubble Space Telescope Cycle 5 (1995) Phase II Proposal ! Id: 5969 - 1995/02/28 ! ! 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: Doug Van Orsow ! Phone: 410 338-4568 , E-mail: vanorsow@stsci.edu ! ! The partially completed template was generated from a Phase I proposal. ! Date generated: Sun Dec 18 09:49:22 EST 1994 ! Proposal_Information ! Section 4 Title: Large Population Studies of Globular Clusters Proposal_Category: GO Scientific_Category: Stellar Populations Cycle: 5 Investigators PI_name: Flavio Fusi Pecci PI_Institution: Osservatorio Astronomico CoI_Name: Francesco R. Ferraro CoI_Institution: Osservatorio Astronomico di Bologna Contact: N ! Y or N (designate at most one contact) CoI_Name: Carla Cacciari CoI_Institution: Osservatorio Astronomico di Bologna Contact: Y CoI_Name: Luciana Federici CoI_Institution: Osservatorio Astronomico di Bologna Contact: N CoI_Name: Roberto Buonanno CoI_Institution: Osservatorio Astronomico di Roma Contact: N CoI_Name: Carlo Corsi CoI_Institution: Osservatorio Astronomico di Roma Contact: N CoI_Name: Giacinto Iannicola CoI_Institution: Osservatorio Astronomico di Roma Contact: N CoI_Name: Robert T. Rood CoI_Institution: University of Virginia Contact: N CoI_Name: Ben Dorman CoI_Institution: University of Virginia Contact: N Abstract: Our long term goal is to obtain very accurate photometric data of a complete sample of Post-Main Sequence (PMS) stars over the entire area of the cluster for a sample of ``prototype'' Galactic Globular Cluster (GGCs). During Cycle 4, 6 hours have been allocated to this program for observing the intermediate metallicity GGC M3. With the present program we shall take WFPC2 observations (in UV, U, V, and I bands) of M92, a very low metallicity GGC. The acquisition of a complete sample of PMS stars will allow us to construct Luminosity Functions (LFs) of stars in any PMS phase. LFs are the most powerful observable tool for testing stellar evolutionary models (e.g. the accuracy of the input physics, the reliability of canonical assumptions, etc.) and have useful applications in several areas, providing, e.g., the most accurate check of the ``stellar clock'' used in dating globular clusters. Our large samples also survey very fast evolutionary and rare (trace) stellar types (e.g. UV-bright stars, blue stragglers, binaries) along with their radial distributions, which will provide fundamental information for internal cluster dynamics and for the origin of UV light from elliptical galaxies. In addition, a pair of very deep exposures in V,I will be taken at two external positions, where the crowding is less severe. These will be used to study the faint end of the luminosity and mass functions of main sequence stars as a function of radial distance. Questions Observing_Description: We propose to obtain WFPC2 observations of the Galactic globular cluster M92 (whose main parameters are listed below) using 4 filters, i.e. F255W, F336W, F555W, F814W. The PC will be positioned on the cluster center and will cover an area of approximately 17 arcsec radius at the higher spatial resolution, while the WFC will cover an additional external area of approximately 2.5 arcmin radius over about 3/4 of the cluster, at a lower spatial resolution. Its lower space resolution is adequate to our needs thanks to the decreased stellar crowding. Ground-based CCD observations will cover the external part of the cluster, the two together providing as complete a mapping as can presently be obtained. Thanks to the restored HST optical performances it will be possible to detect and measure individual stars in all parts of the cluster, including the very central regions. Since the primary aim of this program is to obtain accurate photometric measurements for all the evolved stars, the observations have been planned to optimize both the degree of completeness (down to a fixed magnitude limit, even at the very center of the cluster) and the photometric quality of the individual measures. Hence, the adopted exposure times are adequate to reach S/N=50 in the V and I filters and S/N=30 in the U filter for a G0V star 2 mag below the turnoff, and S/N=10 in the UV filter F255W for F0 stars at the TO level. The V and I exposures will be subdivided into sets of sub-exposures short enough to avoid severe blooming from the brightest (V~13) M0 giants, which would introduce some degree of incompleteness and limit accuracy especially in the very crowded central regions. A few very short V and I exposures will also be taken for non-saturated photometry of the brighest part of the CM diagram. In addition, pairs of very deep V and I exposures will be taken at radial distances of 1.3 and 2.6 arcmin from the cluster center, in order to study the faintest part of the luminosity and mass functions (around absolute luminosity M(V)=+11 and mass M=0.10 Mo), as a function of radial distance. This will provide important information on the structure and dynamics of the cluster. The exposure times have been computed by adopting a readout noise of rn = 14e in the U, V, and I bands and rn = 7e in the UV band. The parameters used for the S/N (or exposure time) calculation are those specified in the WFPC2 Handbook, Version 2.0 May 1994, using the algorithm (S/N)^2=I^2/(I+B) since our observations are not background-dominated. All exposures will be ``dithered'' by 14.5 diagonal pixels in the PC, in order to identify and remove hot pixels and cosmic rays, recover spatial resolution and improve the photometric sampling and accuracy. NGC 6341 (M92): V(TO)=19 E(B-V)=0.02 [Fe/H]=-2.15 Log Rho=3.6 Real_Time_Justification: None Calibration_Justification: No non-standard calibration observations are needed, however see the Observing Description section above for dithering. Additional_Comments: Fixed_Targets ! Section 5.1 Target_Number: 1 Target_Name: NGC6341 Alternate_Names: M92 Description: STELLAR CLUSTER, GLOBULAR CLUSTER Position: RA=17H 17M 7.3S +/- 0.1S, DEC=+43D 8' 11.0" +/- 1" Equinox: 2000 Flux: SURF(V)=15.46 +/- 0.1, B-V=0.62, E(B-V)=0.02 Comments: Above flux values refer to the integrated cluster, for ACQ purposes only. For individual stars see observing description. Visits ! Section 6 Visit_Number: 01 Visit_Requirements: ! Section 7.1 On_Hold_Comments: Visit_Comments: Exposure_Number: 1 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F336W Wavelength: Optional_Parameters: ATD-GAIN=15, CR-SPLIT=0.5 Number_of_Iterations: 1 Time_Per_Exposure: 2000S Special_Requirements: Exposure_Number: 2 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: ATD-GAIN=15, CR-SPLIT=0.5 Number_of_Iterations: 1 Time_Per_Exposure: 200S Special_Requirements: Exposure_Number: 3 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: ATD-GAIN=15, CR-SPLIT=0.50 Number_of_Iterations: 1 Time_Per_Exposure: 2.4S Special_Requirements: Exposure_Number: 4 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: ATD-GAIN=15, CR-SPLIT=0.5 Number_of_Iterations: 1 Time_Per_Exposure: 4S Special_Requirements: Exposure_Number: 5 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: ATD-GAIN=15, CR-SPLIT=0.5 Number_of_Iterations: 2 Time_Per_Exposure: 140S Special_Requirements: Exposure_Number: 6 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F255W Wavelength: Optional_Parameters: CR-SPLIT=0.5 Number_of_Iterations: 1 Time_Per_Exposure: 1100S Special_Requirements: END ORBIT Exposure_Number: 7 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: ATD-GAIN=15, CR-SPLIT=0.50 Number_of_Iterations: 1 Time_Per_Exposure: 2.4S Special_Requirements: POS TARG 0.467, 0.467 Exposure_Number: 8 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F336W Wavelength: Optional_Parameters: ATD-GAIN=15, CR-SPLIT=0.5 Number_of_Iterations: 1 Time_Per_Exposure: 1800S Special_Requirements: POS TARG 0.467, 0.467 Exposure_Number: 9 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: ATD-GAIN=15, CR-SPLIT=0.5 Number_of_Iterations: 1 Time_Per_Exposure: 200S Special_Requirements: POS TARG 0.467, 0.467 Exposure_Number: 10 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: ATD-GAIN=15, CR-SPLIT=0.5 Number_of_Iterations: 1 Time_Per_Exposure: 200S Special_Requirements: POS TARG 0.467, 0.467 Exposure_Number: 11 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: ATD-GAIN=15, CR-SPLIT=0.5 Number_of_Iterations: 1 Time_Per_Exposure: 140S Special_Requirements: POS TARG 0.467, 0.467 Exposure_Number: 12 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: ATD-GAIN=15, CR-SPLIT=0.5 Number_of_Iterations: 1 Time_Per_Exposure: 4S Special_Requirements: POS TARG 0.467, 0.467 Exposure_Number: 13 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F255W Wavelength: Optional_Parameters: CR-SPLIT=0.5 Number_of_Iterations: 1 Time_Per_Exposure: 1300S Special_Requirements: POS TARG 0.467, 0.467; END ORBIT ! ------------------------------------------------------ ! ! Visit_Number: 02 ! Visit_Requirements: SAME ORIENT AS 01 ! ! On_Hold_Comments: ! Visit_Comments: Exposure_Number: 14 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: CR-SPLIT=0.5 Number_of_Iterations: 1 Time_Per_Exposure: 1100S Special_Requirements: POS TARG 77.78, 77.78 Exposure_Number: 15 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: CR-SPLIT=0.5 Number_of_Iterations: 1 Time_Per_Exposure: 1100S Special_Requirements: POS TARG 77.78, 77.78; END ORBIT Exposure_Number: 16 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: CR-SPLIT=0.5 Number_of_Iterations: 1 Time_Per_Exposure: 1100S Special_Requirements: POS TARG 78.247, 78.247 Exposure_Number: 17 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: CR-SPLIT=0.5 Number_of_Iterations: 1 Time_Per_Exposure: 1300S Special_Requirements: POS TARG 78.247, 78.247; END ORBIT !---------------------------------------------- ! ! Visit_Number: 03 ! Visit_Requirements: SAME ORIENT AS 01 ! ! On_Hold_Comments: ! Visit_Comments: Exposure_Number: 18 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: CR-SPLIT=0.5 Number_of_Iterations: 1 Time_Per_Exposure: 900S Special_Requirements: POS TARG 155.56, 155.56 Exposure_Number: 19 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: CR-SPLIT=0.5 Number_of_Iterations: 1 Time_Per_Exposure: 1000S Special_Requirements: POS TARG 155.56, 155.56; END ORBIT Exposure_Number: 20 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F814W Wavelength: Optional_Parameters: CR-SPLIT=0.5 Number_of_Iterations: 1 Time_Per_Exposure: 1100S Special_Requirements: POS TARG 156.027, 156.027 Exposure_Number: 21 Target_Name: NGC6341 Config: WFPC2 Opmode: IMAGE Aperture: PC1-FIX Sp_Element: F555W Wavelength: Optional_Parameters: CR-SPLIT=0.5 Number_of_Iterations: 1 Time_Per_Exposure: 1300S Special_Requirements: POS TARG 156.027, 156.027; END ORBIT 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: ! ! Via Zamboni 33,40126 Bologna, ! ITALY ! ! Ship_Via: UPS ! UPS (2-day) or OVERNIGHT ! Overnight shipping done at PI expense Recipient_Email: ! 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