Any association between a planetary nebula (PN) and a Galactic open star cluster is an extremely valuable and potent astrophysical tool. This is because the accurate (<10%) cluster distance, as determined from a high quality color-magnitude diagram (CMD), constrains the physical parameters of the PN and its central star (CSPN) to exceptional precision. The age, and hence mass of the progenitor star can also be very tightly constrained from cluster isochrones. CSPN photometry also allows precise determination of its intrinsic luminosity and mass. The mass of the progenitor star, which can be related to the chemistry of the resulting PN (from spectroscopy), provides a rare additional datum for the fundamental white dwarf (WD) initial-to-final mass relation (IFMR) which intimately links WD properties to their main-sequence progenitors. A robust IFMR is a key component of using WD luminosity functions to constrain the age of the Galactic disk (field WD population) and open clusters (cluster population) and is also key to the build up of carbon and nitrogen in galaxies. We have discovered a unique PN/open cluster association to add to the IFMR. This single-object proposal is designed to exploit the science inherent in this remarkable discovery.

We plan to use WFC3 with the following broad filters: F200LP and F350LP to assure that the CS is correctly identified and to determine the UV continuum; the F555W and F814W filters will allow a determination of the visible continuum (since the nebula is well resolved) and also allow the construction of a deep CMD for the host cluster. The continuum exposures will be centered on the cluster, and line-dithered to ameliorate detector artifacts (particularly for the PN central star). We also plan an exposure of the PN with the F502N narrow-band filter (centered in UVIS1) to provide the detailed nebular microstructure in [O_III]. The broad wavelength coverage of these filters beginning in the near-UV where the star will be brightest gives us the opportunity to correctly identify the PN central ionizing star, which we have predicted to have V~23.5+/-1.0. A major additional by-product of the WFC3 field of view is that it is nearly identical to the size of the cluster, which affords the opportunity of a complete color-magnitude diagram for the host cluster. The existing literature CMDs from ground based observations are of rather low quality and suffer from image blending and field star contamination within this compact cluster. In detail, we need exposures centered on the cluster of ~0.5 min plus >10 min in each of F555W and F814W to cover the full dynamic range of the cluster stars with S/N>=30 from above the red clump (V=16.5) to the faint CSPN (V~23.5). We also need the UV continuum with a 14 min and a 16~min exposure in F200LP and F350LP, respectively, which will yield S/N=20. Finally, we plan a ~15 min exposure in F502N, which will yield a S/N ~10 per resolution element. Splitting all exposures (except for the two at 30~s) and allowing for dither offsets between pairs for continuum exposures, plus orbit overheads and managing buffer dumps, requires 2 orbits for this program. RESOLVED STELLAR POPULATIONS 12 false 0.0 0.0 false false false false SUPPORTED STELLAR CLUSTER EJECTA EMISSION LINE NEBULA OPEN CLUSTER Coordinates of PN from Parker, Q.A., et al. 2011, MNRAS, 413, 1835 J2000 J2000 log F(Hb)=-13.31 ± 0.02; E(B-V)=0.75 STELLAR CLUSTER EMISSION LINE NEBULA OPEN CLUSTER Coordinates of Open Cluster (center) from Parker, Q.A., et al. 2011, MNRAS, 413, 1835 WFC3/UVIS Imaging No No F200LP WFC3/UVIS Imaging No No F502N WFC3/UVIS Imaging No No F555W WFC3/UVIS Imaging No No F814W WFC3/UVIS Imaging No No F350LP POS-TARG DITHER 0.145 LINE false false 2 46.84 WFC3-UVIS-DITHER-LINE 1 false The scheduling data was generated by CASM 19.3. CASM was run in Phase II mode. (Tic-Visit :proposal-id 12518 :visit-id "01" :proposal-version -1 :trans-version "20110509" :date "22-Jun-2011 15:12:44.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 3465008 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12518 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12518 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 3266 :al-overhead-at-end 116 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3599 :pcs-gap 0 ) (Tic-Orbit :proposal-id 12518 :visit-id "01" :orbit-number 2 :pcs-time 222 :si-vis-utilization 3376 :al-overhead-at-end 118 :internal-dur-at-end 670 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3599 :pcs-gap 0 ) false 2 0