! Proposal 6731, submission 1 ! PI: Robin Ciardullo ! Received Wed Feb 7 13:14:55 EST 1996 ! From: johnf@astro.psu.edu ! +====================+ ! | PED OUTPUT PRODUCT | ! +====================+ ! ! /auto/kzin/home/kzin/johnf/Research/HST/6731.prop ! Generated by PREPROCESSOR, version 6.0e ! Date: Wed Feb 7 12:47:17 EST 1996 Proposal_Information Title: Exploring PN Production as a Probe of Elliptical Galaxy Stellar Populations Proposal_Category: GO Scientific_Category: GALAXIES & CLUSTERS Cycle: 6 Investigators PI_Name: Robin Ciardullo PI_Institution: The Pennsylvania State University CoI_Name: John Feldmeier CoI_Institution: The Pennsylvania State University Contact: Abstract: In addition to being an excellent distance indicator, the O III Lambda 5007 planetary nebula luminosity function (PNLF) is potentially a powerful probe of stellar population. Values for the production rate of bright PN vary by almost an order of magnitude between different galaxies: galaxies with bright absolute magnitudes, strong Mg_2 indices, and large UV upturns are systematically deficient in bright planetary nebulae. This behavior has been cited as support for models of non- traditional post-asymptotic branch evolution ( i.e., the post- early-AGB, and AGB-manque scenarios) in metal-rich systems, and it gives us a tool with which to examine the population of nearby elliptical galaxies. There is, however, one problem in associating the planetary nebula production rate with UV flux or Mg_2 index. Because of crowding and signal-to-noise considerations, groundbased measurements of the PNLF are confined to the outer parts of galaxies, whereas absorption line spectroscopy and UV photometry are restricted to the bright inner regions. We propose to use the Planetary Camera of the Hubble Space Telescope to measure the O III planetary nebula luminosity function in the centers of two nearby ellipticals. These data will quantitatively calibrate the correlations between PN production, UV flux, and the spectroscopic indices of Mg, Fe, and H Beta, allowing PN to be used as a tool for population studies. Questions Observing_Description: We wish to measuring the planetary nebula luminosity function for two galaxies: NGC 3379 and NGC 4278. The technique for doing this involves taking on-band/off-band images in O III Lambda 5007. The on-band filter is F502N, which has a central wavelength of 5013 Angstrom and is 27 Angstrom wide; the off-band filter is F547M, which is 486 Angstrom wide. The recessional velocities of NGC 3379 and NGC 4278 are 920 and 649 km-s^-1, respectively, so both galaxies fall within the velocity range of the F502N filter. To estimate the exposure time needed to sample the top ~ 1 mag of the PNLF, we begin by noting that the apparent distance modulus of both galaxies is (m-M) = 30.0 (Ciardullo, Jacoby & Ford 1989; Jacoby, Ciardullo, & Harris 1995). Since the PNLF cutoff magnitude is M^* ~ -4.5, this implies that we must reach m_5007 ~ 26.5, where m_5007 is related to monochromatic flux by m_5007 = -2.5log F_5007 - 13.74 Using the F502N filter specifications in the WFPC2 Instrument Handbook (1995), the exposure times necessary to do this with the Planetary Camera at a location 1" from the galaxies' centers is 2.6 hr. This number assumes a signal-to-noise of 10 is required to obtain a statistically complete PN sample (Ciardullo Etal 1987; Hui Etal 1993). Based on their surface brightness profiles, we can expect to find between 10 and 50 PN in the central 15" of NGC 4278 and between 15 and 75 PN in the same region of NGC 3379, depending on the value of alpha_2.5. Real_Time_Justification: None The outer regions of the proposed galaxies have already been surveyed from planetary nebulae. The data for NGC 3379 is published; a paper describing the results for NGC 4278 has been submitted to the Ap. J. Calibration_Justification: Additional_Comments: If possible, we would like our exposures oriented so that we can link previous ground-based planetary nebulae measurements with the new HST measurements of the cores. This will allow us to put both data on common photometric and astrometric systems. Fixed_Targets Target_Number: 1 Target_Name: NGC3379-NUC Alternate_Names: M105,UGC05902 Description: GALAXY,ELLIPTICAL, Position: RA=10H 45M 11S +/- 2.5",DEC=12D 50' 48" +/- 2.5" Equinox: B1950 RV_or_Z: V = 920 RA_PM: Dec_PM: Epoch: Annual_Parallax: Flux: V = 9.4+/-0.1 B-V = 1.0+/-0.1 Comments: Target_Number: 2 Target_Name: NGC4278-NUC Alternate_Names: UGC07386 Description: GALAXY,ELLIPTICAL Position: RA=12H 17M 36.20S +/- 0.025S,DEC=29D 33' 29.0" +/- 0.375" Equinox: 1950 RV_or_Z: V=+649 RA_PM: Dec_PM: Epoch: Annual_Parallax: Flux: V = 10.1+/-0.1 B-V = 1.0+/-0.1 Comments: Visits Visit_Number: 01 Visit_Requirements: On_Hold_Comments: Visit_Comments: Exposure_Number: 11 Target_Name: NGC3379-NUC Config: WFPC2 Opmode: IMAGE Aperture: PC1 Sp_Element: F547M Wavelength: Optional_Parameters: Number_of_Iterations: 5 Time_Per_Exposure: 120S Special_Requirements: MAX DUR 100% Comments: Exposure_Number: 12 Target_Name: NGC3379-NUC Config: WFPC2 Opmode: IMAGE Aperture: PC1 Sp_Element: F502N Wavelength: Optional_Parameters: CR-SPLIT=0.0 Number_of_Iterations: 1 Time_Per_Exposure: 20M Special_Requirements: MAX DUR 150% NO SPLIT Comments: Exposure_Number: 13 Target_Name: NGC3379-NUC Config: WFPC2 Opmode: IMAGE Aperture: PC1 Sp_Element: F502N Wavelength: Optional_Parameters: Number_of_Iterations: 2 Time_Per_Exposure: 82M Special_Requirements: MAX DUR 150% Comments: Visit_Number: 02 Visit_Requirements: ORIENT 315D TO 90D On_Hold_Comments: Visit_Comments: Exposure_Number: 21 Target_Name: NGC4278-NUC Config: WFPC2 Opmode: IMAGE Aperture: PC1 Sp_Element: F547M Wavelength: Optional_Parameters: Number_of_Iterations: 5 Time_Per_Exposure: 120S Special_Requirements: MAX DUR 100% Comments: Exposure_Number: 22 Target_Name: NGC4278-NUC Config: WFPC2 Opmode: IMAGE Aperture: PC1 Sp_Element: F502N Wavelength: Optional_Parameters: CR-SPLIT=0.0 Number_of_Iterations: 1 Time_Per_Exposure: 20M Special_Requirements: MAX DUR 150% Comments: Visit_Number: 03 Visit_Requirements: ORIENT 315D TO 90D On_Hold_Comments: Visit_Comments: Exposure_Number: 24 Target_Name: NGC4278-NUC Config: WFPC2 Opmode: IMAGE Aperture: PC1 Sp_Element: F502N Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 2700S Special_Requirements: MAX DUR 150% Comments: Visit_Number: 04 Visit_Requirements: ORIENT 315D TO 90D On_Hold_Comments: Visit_Comments: Exposure_Number: 24 Target_Name: NGC4278-NUC Config: WFPC2 Opmode: IMAGE Aperture: PC1 Sp_Element: F502N Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 2700S Special_Requirements: MAX DUR 150% Comments: Visit_Number: 05 Visit_Requirements: ORIENT 315D TO 90D On_Hold_Comments: Visit_Comments: Exposure_Number: 24 Target_Name: NGC4278-NUC Config: WFPC2 Opmode: IMAGE Aperture: PC1 Sp_Element: F502N Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 2700S Special_Requirements: MAX DUR 150% Comments: Visit_Number: 06 Visit_Requirements: ORIENT 315D TO 90D On_Hold_Comments: Visit_Comments: Exposure_Number: 24 Target_Name: NGC4278-NUC Config: WFPC2 Opmode: IMAGE Aperture: PC1 Sp_Element: F502N Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 2700S Special_Requirements: MAX DUR 150% Comments: Data_Distribution ! Defaults indicated; change if desired Medium: 8MM Blocking_Factor: 10 Ship_To: PI_Address Ship_Via: UPS Recipient_Email: ! Let us know what you think of this template and software! ! Please send a list of your likes and dislikes to your Program Coordinator