9826( 12) - 02/18/04 13:04 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 9826 Version: 12 Check-in Date: 18-Feb-2004 13:02:41 1.Proposal Title: The Planetary Nebula K648 in the Globular Cluster M15 ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 12 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Dr. Luciana Bianchi The Johns Hopkins University CoI: Dr. James Herald The Johns Hopkins University N ------------------------------------------------------------------------------------ 5. Abstract We propose STIS spatially resolved UV spectra (long slit), and echelle UV spectra, of the Planetary Nebula (PN) K648 in M15, one of the few PN known in globular clusters. The data will provide two crucial tests to clarify the still elusive nature of this object, in particular whether it evolved from a coalesced binary (Bianchi et al. 2001). Such a result would have general implications for better understanding the evolution of close binaries (common envelope phase), especially important in the globular cluster environment, and the formation of bi-polar nebulae. We will try to reveal the presence (and dimensions) of a disk surrounding the central star by modeling the high resolution profile of the CIV wind line. The stellar parameters (and possible disk presence) can be constrained only by the requested STIS spectra. Complementary FUSE spectra in the far-UV (905-1187A) will be analysed concurrently, to derive the circumstellar molecular and neutral hydrogen, and the extinction. ------------------------------------------------------------------------------------ 9826( 12) - 02/18/04 13:04 - [ 2] Observations Description ------------------------ Primary. We need STIS long slit spectra with G140L and G230L . We aim at a S/N of 50 (over most of the wavelength range) on the central star spectrum, to be able to detect (at degraded resolution, but significant flux level) the much fainter nebular continuum emission in the spatially resolved spectra. We will use a 0.2"' wide long slit, For the high resolution E140M exposure, we pose a minimum requirement of S/N=20 at a resolution of 25 km/s (i.e. rebinning by a factor of 4 the full resolution of the E140M, 6.5 km/s, which is sufficient for our purpose - see Fig.4-5)The E140M exposure will be taken through the 0.2'x0.2' slit.Using the on-line STIS exposure time calculator (ETC) and the flux from the FOS spectra (Fig.s 1 and 2), we estimate exposure times of 7.5, 6.5, and 60 minutes respectively for the three settings. PARALLEL: With WFPC2, taking into account the additional over-heads for readouts of the parallel images, in two orbits of parallels we can reach about 3 magnitudes below the turn-off of M15, i.e. approximately the magnitude of CVs in quiescence with S/N=40 in U, B, V and I (15, 12, 2.5, 5 min respectively). Additionally, with a 7.5 min. exposure in F255W, we will reach the turn off magnitude (S/N=20) thus definitely detect all the BSS in the near-UV band too, which is useful to refine the temperature. Acquisition. Because of the crowded field, we will offset from a nearby brighter star. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 9826( 12) - 02/18/04 13:04 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 K648-OFFSET STAR, K III-I RA=21H29M55.68S +/- 2.0", J2000 V = 12.83+/-0.2 DEC=+12D10'45.47" +/- 2.0", B-mag = 14.29 PLATE-ID=02V2 Coordinate Source: HST_IMAGE Comments: Coordinates measured on WFPC2 image U5B8010HR from chip containing both target and offset star. Note: shifts of up to 2" between known star coordinates measured on the WFPC2 image and from in the catalogs. Nearest bright neighbor to offset star has mag(555W) = 14.72 and is 3.8" away Relative coordinates between target and offset star should be accurate. 2 K648 STAR, PLANETARY NEBULA RA-OFF=3.7864S +/- 0.1S, DEC- J2000 V = 14.95+/-0.2 CENTRAL STAR OFF=-19.319" +/- 0.1", FROM 1, PLATE-ID=02V2 Coordinate Source: HST_IMAGE Comments: Offset coordinates relative to offset star: RA 00 00 3.7864 Dec -00 00 19.319 Absolute coordinates of target: RA 21 29 59.4640 Dec +12 10 26.140 9826( 12) - 02/18/04 13:04 - [ 4] TARGET LIST Generic Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Selection Criteria | Flux data No | Name | Description | | ------------------------------------------------------------------------------------------------------------------------------------ 3 PARALLEL-IN- STELLAR CLUSTER, V = 14.0+/-1.0 M15 GLOBULAR CLUSTER ------------------------------------------------------------------------------------------------------------------------------------ 9826( 12) - 02/18/04 13:04 - [ 5] Visit: 01 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 K648-OFFSET STIS/C ACQ 50CCD MIRROR 1 1 S SEQ 1-7 NON-INT CD ------------------------------------------------------------------------------------------------------------------------------------ 2 K648 STIS/F ACCUM 52X0.2 G140L 1425 1 450 S PAR 4-5 WITH 2-3 UV-MAM A ------------------------------------------------------------------------------------------------------------------------------------ 3 K648 STIS/N ACCUM 52X0.2 G230L 2376 1 397 S UV-MAM A ------------------------------------------------------------------------------------------------------------------------------------ 4 ANY WFPC2 IMAGE WFALL F814W CR-SPLIT=0.5,CR-TOLERANCE=0.2 1 300 S ------------------------------------------------------------------------------------------------------------------------------------ 5 ANY WFPC2 IMAGE WFALL F255W CR-SPLIT=.5,CR-TOLERANCE=0.2 1 450 S ------------------------------------------------------------------------------------------------------------------------------------ 6 K648 STIS/F ACCUM 0.2X0.2 E140M 1425 1 680 S PAR 7 WITH 6 UV-MAM A Comments: extend as long as possible to fill the orbit ------------------------------------------------------------------------------------------------------------------------------------ 7 ANY WFPC2 IMAGE WFALL F170W CR-SPLIT=0.5,CR-TOLERANCE=0.2 1 595 S ------------------------------------------------------------------------------------------------------------------------------------ 8 K648 STIS/F ACCUM 0.2X0.2 E140M 1425 1 2795 S PAR 9-12 WITH 8 UV-MAM A Comments: extend as long as possible to fill the orbit ------------------------------------------------------------------------------------------------------------------------------------ 9 ANY WFPC2 IMAGE WFALL F555W CR-SPLIT=0.5,CR-TOLERANCE=0.2 1 150 S Comments: make sure CRsplit ------------------------------------------------------------------------------------------------------------------------------------ 10 ANY WFPC2 IMAGE WFALL F439W CR-SPLIT=.5,CR-TOLERANCE=.2 1 720 S ------------------------------------------------------------------------------------------------------------------------------------ 11 ANY WFPC2 IMAGE WFALL F336W CR-SPLIT=.5,CR-TOLERANCE=0.2 1 538 S ------------------------------------------------------------------------------------------------------------------------------------ 12 ANY WFPC2 IMAGE WFALL F336W CR-SPLIT=NO,CR-TOLERANCE=0.2 1 269 S ------------------------------------------------------------------------------------------------------------------------------------ 9826( 12) - 02/18/04 13:04 - [ 6] Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Visit Id| Exp Id |Primary |Secondary |Iteration |CR-SPLIT |Orbit Num |Duration | |Pattern Pos |Pattern Pos |Num |Num | | ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Visit Id| Exp Id |Primary |Secondary |Iteration |CR-SPLIT |Orbit Num |Duration | |Pattern Pos |Pattern Pos |Num |Num | | ------------------------------------------------------------------------------------------------------------------------------------ 01 1 none none none none 1 tbd 01 2 none none none none 1 tbd 01 3 none none none none 1 tbd 01 4 none none none 1 1 tbd 01 4 none none none 2 1 tbd 01 5 none none none 1 1 tbd 01 5 none none none 2 1 tbd 01 6 none none none none 1 tbd 01 7 none none none 1 1 tbd 01 7 none none none 2 1 tbd 01 8 none none none none 2 tbd 01 9 none none none 1 2 tbd 01 9 none none none 2 2 tbd 01 10 none none none 1 2 tbd 01 10 none none none 2 2 tbd 01 11 none none none 1 2 tbd 01 11 none none none 2 2 tbd 01 12 none none none none 2 tbd 9826( 12) - 02/18/04 13:04 - [ 7] Summary Form for Proposal 9826 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures 50CCD 52X0.2 WFALL 0.2X0.2 ------------------------------------------------------------------------------------------------------------------------------------ Configurations STIS/CCD STIS/FUV-MAMA STIS/NUV-MAMA WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ ACCUM IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=0.5 CR-TOLERANCE=0.2 CR-SPLIT=.5 CR-TOLERANCE=.2 CR-SPLIT=NO ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements SEQ 1-7 NON-INT PAR 4-5 WITH 2-3 PAR 7 WITH 6 PAR 9-12 WITH 8 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR G140L G230L F814W F255W E140M F170W F555W F439W F336W ------------------------------------------------------------------------------------------------------------------------------------ Target Names K648-OFFSET K648 ANY ------------------------------------------------------------------------------------------------------------------------------------ Wavelengths 1425 2376 ------------------------------------------------------------------------------------------------------------------------------------