!__Proposal-Section__ !6125 ! Hubble Space Telescope Cycle 5 (1995) Phase II Proposal Template ! $Id: 6125,v 15.1 1996/08/07 15:10:06 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: Christian Ready ! Phone: 410 338-4546 , E-mail: ready@stsci.edu ! ! This partially completed template was generated from a Phase I proposal. ! Date generated: Mon Dec 19 08:27:22 EST 1994 ! Proposal_Information ! Section 4 Title: Imaging and Spectroscopy of SN 1885 in M31 Proposal_Category: GO Scientific_Category: Interstellar Medium Cycle: 5 Investigators PI_name: Robert Fesen PI_Institution: Dartmouth College CoI_Name: Andrew Hamilton CoI_Institution: University of Colorado Contact: ! Y or N (designate at most one contact) Abstract: ! Free format text (please update) We request WFC images and FOS spectra of the remnant of S Andromedae, the historic 1885 supernova which occurred in the M31 bulge. Our 1988 discovery of this remnant as an unresolved dark spot of Fe I 3860 Angstrom \ absorption silhouetted against M31 suggests it contains a large quantity of cold, iron-rich ejecta expanding at up to 5000 km/s. These properties together with its bulge location are consistent with a SN I classification despite a peculiarly fast light curve. , Absorption line studies offer powerful new probes into the dynamical and chemical properties of SN ejecta. FOS Fe I LambdaLambda3720,3860 absorption profiles of the S And remnant will allow the first determination of an SN I's average iron density as a function of radius in the freely expanding ejecta. Only HST makes such a study possible. The remnant's estimated diameter is just 0.3'' - 0.5''. HST's superb PSF, small FOS apertures, and accurate, blind-offset positioning are crucial for this program. Cycle 1's degraded optics and M31's steep continuum fall-off below 3000 Angstrom \ prevented a detection in the UV. Attempted 3000 - 4000 Angstrom \ spectra from the ground have failed due to severe bulge light contamination on this sub-arcsec size target. WFC2 images will provide a precise remnant location for accurate FOS aperture positioning plus Fe I size and expansion asymmetry information. Questions ! Free format text (please update) Observing_Description: The orbital visibility of M31 is 54 minutes. We wish to obtain two WFC images of S And in EARLY ACQUISITION mode and then use these to determine accurate offset positioning of the remnant so precise FOS aperture targeting can be made. We would like to have a SNR of 20 or greater to clearly detect the remnant, check for expansion asymmetries, and measure accurate offsets. All WFC exposures will be CR-SPLIT to facilitate removal of the numerous cosmic rays. 1) For estimating WFC image exposures, we used published photometry of the M31 bulge (Kent 1983), IUE and HST flux measurements of the bulge near S And, and our original discovery groundbased 3880 Angstrom \ images. S And is just 16 arcsec from the nucleus and there is a very steep gradient towards the nucleus (Kent 1983) and several small neighboring dust clouds. The surface brightness of the bulge at S And's position is about V = 14.0 mag. From the WFPC2 Handbook, we find the FQUVN-B filter (that is, the ``on'' band filter for detecting Fe I 3860 blueshifted absorption) has a intQT dLambda/Lambda = 0.00028. With a surface brightness of V = 14 mag/sq arcsec, an AB_V appropriate for the bulge at 3800 Angstrom \ (Table 6.1; for gE galaxy AB = 2.0), we then calculate using Eq. 6.1 a N(e) = 28 electrons s^-1 arcsec^-2. This means that each 0.1'' WFC pixel will see 1/100 of this or N(e) = 0.28 e^- s^-1 pixel^-1. This agrees within a factor of two with an estimate using our groundbased 3880 Angstrom \ images. A similar calculation for the ``off-band'' FQUVN-C filter gives N(e) = 0.38 e^- s^-1 pixel^-1. Sky background and readout noise are negligible. With 54 minutes orbital visibility minus the 12 minutes needed for GS Acquisition, that leaves 42 min for exposures and overhead. We can fit three 10 min exposures plus 8 minutes overhead per orbit. Since the count rate is higher for the off-band image, we would take this image in the first orbit, leaving the on-band image (FQUVN-B) for the next orbit which has only a 6 min GS re-acq. This would allow two 19 min CR-SPLIT exposures, each with 5 min OH, completely filling the orbit. This would give a 38 minute total FQUVN-B on-band Fe I image, with total counts around the target at 638 cts/pixel with a SNR = 23. The 30 minute off-band FQUVN-C images will collect 685 cts/pixel with a SNR = 24. Thus 2 orbits are needed for imaging, one for each filter. The remnant will occupy 9 to 25 pixels and should be well detected with these pixel counts. 2) FOS spectra need to cover the strong optical Fe I resonance lines at 3720 and 3860 Angstrom. The G400H grating with the Red Digicon will do this and actually peaks in sensitivity near these wavelengths (Fig. 1.2.3 FOS Handbook May 1994). To match the expected size of the remnant and to also pickup a neighboring section of the M31 bulge for comparison, we will use the 0.5-pair FOS apertures. These will sample both the target (S And) and sky (bulge light). HST makes studying S And feasible because of its precise positioning (+/- 0.02''; pg 43, HST Call for Proposals book). The early ACQ WFC images will yield accurate remnant size and position information necessary for accurate FOS aperture positioning. Since S And's dark Fe I absorption spot cannot be directly positioned on, we will use (like we did in Cycle 1) an offset star (mag 14) located 17.0'' west and 84.5'' north from S And (these measurements will be improved via the WFC images.) Acquisition of this star (12 min), and the series of four peakup target acquisitions using the 0.5'' apertures will take 7+ 14+ 12 + 17 minutes. Since the orbital visibility for M31 is 54 minutes, all but the last 17 minute stage can be fit into the first orbit (9 min are left unused). In Orbit 2 following re-acq (6 min) and the 17 min fourth stage, 25 minutes is needed to do the blind offset from the offset star to S And (page 18), leaving 6 min lost at the end. On Orbit 3 after re-acq, we can take a 42 minute exposure and still have 6 min for FOS/ACCUM overhead. This will be enough to get us a very good spectrum. The expected FOS count rate from the flux of M31's bulge at the S And site can be estimated directly from the Cycle 1 data. These show a rate N = 0.20 counts per diode at 3700 Angstrom \ taking into consideration the larger aperture used (1.0'' pair), the higher resolution of the G270H grating vs G400H grating (i.e. 2.05 vs 3.0 Angstrom \ per diode), and extrapolating from the observed flux at 3200 Angstrom \ to 3800 Angstrom. This count rate is much larger than the FOS/RD dark signal of 0.01 cts/diode. Using the full 42 minutes we have left available in Orbit 3, the spectrum will have a SNR = 16 with 630 total cts/diode. This should be sufficient to detect weak absorption in the wings of the expected 5000 km/s broad profiles (= 60-70 Angstrom \ or 20-23 diodes) for the stronger Fe I lines. Real_Time_Justification: None. We have exhausted what can be practically done from the ground. Calibration_Justification: ! Move appropriate text from Real_Time_Justification Additional_Comments: Fixed_Targets ! Section 5.1 Target_Number:1 Target_Name:NGC224-SN1885 Alternate_Names:M31 Description:ISM,SNR Position:RA=00H 42M 42.930S +/- 0.1S, DEC=+41D 15' 50.60" +/- 1", PLATE-ID=0738 Equinox:J2000 Flux: ! Include at least V and B-V Comments:Target is absorption "dark" spot in bulge of M31 which is the supernova remnant of 1885. Fixed_Targets ! Section 5.1 Target_Number:2 Target_Name:SN1885-OFFSET Alternate_Names: Description:STAR Position:RA=00H 42M 41.312S +/- 0.2S, DEC=+41D 15' 24.13" +/- 1", PLATE-ID=0738 Equinox:J2000 Flux:V=15.0 +/- 1.5 Comments:Off-setting star is 15.0 mag star SW of SN 1885. Target_Number:3 Target_Name:SN1885 Alternate_Names:S-AND Description:ISM,SNR Position:RA=00H 42M 42.882S +/- 0.001S, DEC=+41D 16' 05.02" +/- 0.01", PLATE-ID=0738 Equinox:J2000 Flux:V=17.0 +/- 1.0 Comments:Target is a blind offset from 14 mag star (target 2). Target_Number:4 Target_Name:NGC224 Alternate_Names:M31 Description:GALAXY,SPIRAL Position:RA=00H 42M 44.190S +/- 0.1S, DEC=+41D 16' 08.15" +/- 1", PLATE-ID=0738 Equinox:J2000 Flux:V=14.0 +/- 2.0 Comments:Target is background M31 bulge light near nucleus. Visits ! Section 6 Visit_Number:01 Visit_Requirements: ! Section 7.1 ! Uncomment or copy visit level special requirements needed ! Most of these requirements (including ORIENT) will limit scheduling On_Hold_Comments: Visit_Comments: Exposure_Number:11 ! Section 6.5 Target_Name:NGC224-SN1885 Config:WFPC2 Opmode:IMAGE Aperture:WF3-FIX Sp_Element:FQUVN Wavelength:3916 Optional_Parameters: Number_of_Iterations:1 Time_Per_Exposure:400S Special_Requirements: ! Section 7.2 Exposure_Number:12 ! Section 6.5 Target_Name:NGC224-SN1885 Config:WFPC2 Opmode:IMAGE Aperture:WF3-FIX Sp_Element:FQUVN Wavelength:3916 Optional_Parameters: Number_of_Iterations:1 Time_Per_Exposure:400S Special_Requirements: ! Section 7.2 Exposure_Number:13 ! Section 6.5 Target_Name:NGC224-SN1885 Config:WFPC2 Opmode:IMAGE Aperture:WF3-FIX Sp_Element:FQUVN Wavelength:3916 Optional_Parameters: Number_of_Iterations:1 Time_Per_Exposure:400S Special_Requirements:POS TARG -0.50,-0.50 ! Section 7.2 Exposure_Number:14 ! Section 6.5 Target_Name:NGC224-SN1885 Config:WFPC2 Opmode:IMAGE Aperture:WF3-FIX Sp_Element:FQUVN Wavelength:3916 Optional_Parameters: Number_of_Iterations:1 Time_Per_Exposure:400S Special_Requirements:POS TARG -0.50,-0.50 ! Section 7.2 Exposure_Number:21 ! Section 6.5 Target_Name:NGC224-SN1885 Config:WFPC2 Opmode:IMAGE Aperture:WF4-FIX Sp_Element:FQUVN Wavelength:3839 Optional_Parameters:CR-SPLIT=NO Number_of_Iterations:1 Time_Per_Exposure:500S Special_Requirements: ! Section 7.2 Exposure_Number:22 ! Section 6.5 Target_Name:NGC224-SN1885 Config:WFPC2 Opmode:IMAGE Aperture:WF4-FIX Sp_Element:FQUVN Wavelength:3839 Optional_Parameters:CR-SPLIT=NO Number_of_Iterations:1 Time_Per_Exposure:500S Special_Requirements: ! Section 7.2 Exposure_Number:23 ! Section 6.5 Target_Name:NGC224-SN1885 Config:WFPC2 Opmode:IMAGE Aperture:WF4-FIX Sp_Element:FQUVN Wavelength:3839 Optional_Parameters:CR-SPLIT=NO Number_of_Iterations:1 Time_Per_Exposure:500S Special_Requirements:POS TARG -0.50,-0.50 ! Section 7.2 Exposure_Number:24 ! Section 6.5 Target_Name:NGC224-SN1885 Config:WFPC2 Opmode:IMAGE Aperture:WF4-FIX Sp_Element:FQUVN Wavelength:3839 Optional_Parameters:CR-SPLIT=NO Number_of_Iterations:1 Time_Per_Exposure:500S Special_Requirements:POS TARG -0.50,-0.50 ! Section 7.2 Visits ! Section 6 Visit_Number:02 Visit_Requirements:ON HOLD FOR 1 ! Section 7.1 On_Hold_Comments:Waiting for EARLY ACQ of VISIT 1 WFPC2 IMAGING for precise positional information to insure detection with FOS apertures. Visit_Comments: The WFPC2 images will guide the FOS spectral observations in target offset positioning and aperature selection. The ACQ/PEAK 4 obs. could be dropped and exposure 105 lengthened if target is larger than 0.5 arcsec in dia. Exposure_Number:101 ! Section 6.5 Target_Name:SN1885-OFFSET Config:FOS/RD Opmode:ACQ/PEAK Aperture:4.3 Sp_Element:G400H Wavelength:4000 Optional_Parameters:SCAN-STEP-Y=1.204, SEARCH-SIZE-X=1, SEARCH-SIZE-Y=3 Number_of_Iterations:1 Time_Per_Exposure:1.0S Special_Requirements:ONBOARD ACQ FOR 102 ! Section 7.2 Exposure_Number:102 ! Section 6.5 Target_Name:SN1885-OFFSET Config:FOS/RD Opmode:ACQ/PEAK Aperture:1.0 Sp_Element:G400H Wavelength:4000 Optional_Parameters:SCAN-STEP-X=.602, SCAN-STEP-Y=.602, SEARCH-SIZE-X=6, SEARCH-SIZE-Y=2 Number_of_Iterations:1 Time_Per_Exposure:1.0S Special_Requirements:ONBOARD ACQ FOR 103 ! Section 7.2 Exposure_Number:103 ! Section 6.5 Target_Name:SN1885-OFFSET Config:FOS/RD Opmode:ACQ/PEAK Aperture:0.5 Sp_Element:G400H Wavelength:4000 Optional_Parameters:SCAN-STEP-X=.172, SCAN-STEP-Y=.172, SEARCH-SIZE-X=5, SEARCH-SIZE-Y=5 Number_of_Iterations:1 Time_Per_Exposure:1.0S Special_Requirements:ONBOARD ACQ FOR 104 ! Section 7.2 Exposure_Number:104 ! Section 6.5 Target_Name:SN1885-OFFSET Config:FOS/RD Opmode:ACQ/PEAK Aperture:0.3 Sp_Element:G400H Wavelength:4000 Optional_Parameters:SCAN-STEP-X=.05, SCAN-STEP-Y=.05, SEARCH-SIZE-X=5, SEARCH-SIZE-Y=5 Number_of_Iterations:1 Time_Per_Exposure:10.0S Special_Requirements:ONBOARD ACQ FOR 105 ! Section 7.2 Exposure_Number:105 ! Section 6.5 Target_Name:SN1885 Config:FOS/RD Opmode:ACCUM Aperture:0.5 Sp_Element:G400H Wavelength:4000 Optional_Parameters: Number_of_Iterations:1 Time_Per_Exposure:3000S Special_Requirements: ! Section 7.2 Exposure_Number:106 ! Section 6.5 Target_Name:NGC224 Config:FOS/RD Opmode:ACCUM Aperture:1.0 Sp_Element:G400H Wavelength:4000 Optional_Parameters: Number_of_Iterations:1 Time_Per_Exposure:530S Special_Requirements: ! Section 7.2 Visit_Number:51 Visit_Requirements: ! Section 7.1 On_Hold_Comments: Visit_Comments: HOPR Repeat Visit for failed visit 02. Exposure_Number:200 ! Section 6.5 Target_Name:NGC224 Config:FOS/RD Opmode:ACCUM Aperture:1.0 Sp_Element:G400H Wavelength: Optional_Parameters: Number_of_Iterations:1 Time_Per_Exposure:420S Special_Requirements:EXPAND ! Section 7.2 Exposure_Number:201 ! Section 6.5 Target_Name:SN1885-OFFSET Config:FOS/RD Opmode:ACQ/PEAK Aperture:4.3 Sp_Element:G570H Wavelength: Optional_Parameters:SCAN-STEP-Y=1.23, SEARCH-SIZE-X=1,SEARCH-SIZE-Y=3 Number_of_Iterations:1 Time_Per_Exposure:2.3S Special_Requirements:ONBOARD ACQ FOR 202 ! Section 7.2 Exposure_Number:202 ! Section 6.5 Target_Name:SN1885-OFFSET Config:FOS/RD Opmode:ACQ/PEAK Aperture:1.0 Sp_Element:G570H Wavelength: Optional_Parameters:SCAN-STEP-X=.61, SCAN-STEP-Y=.61, SEARCH-SIZE-X=6, SEARCH-SIZE-Y=2 Number_of_Iterations:1 Time_Per_Exposure:2.5S Special_Requirements:ONBOARD ACQ FOR 203 ! Section 7.2 Exposure_Number:203 ! Section 6.5 Target_Name:SN1885-OFFSET Config:FOS/RD Opmode:ACQ/PEAK Aperture:0.5 Sp_Element:G570H Wavelength: Optional_Parameters:SCAN-STEP-X=.29, SCAN-STEP-Y=.29, SEARCH-SIZE-X=3, SEARCH-SIZE-Y=3 Number_of_Iterations:1 Time_Per_Exposure:2.6S Special_Requirements:ONBOARD ACQ FOR 204 ! Section 7.2 Exposure_Number:204 ! Section 6.5 Target_Name:SN1885-OFFSET Config:FOS/RD Opmode:ACQ/PEAK Aperture:0.3 Sp_Element:G570H Wavelength: Optional_Parameters:SCAN-STEP-X=.11, SCAN-STEP-Y=.11, SEARCH-SIZE-X=4, SEARCH-SIZE-Y=4 Number_of_Iterations:1 Time_Per_Exposure:30.0S Special_Requirements:ONBOARD ACQ FOR 205 ! Section 7.2 Exposure_Number:205 ! Section 6.5 Target_Name:SN1885 Config:FOS/RD Opmode:ACCUM Aperture:0.5 Sp_Element:G400H Wavelength: Optional_Parameters: Number_of_Iterations:1 Time_Per_Exposure:4200S Special_Requirements:EXPAND ! Section 7.2 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: ! ! 6127 Wilder Lab, ! Department of Physics and Astr ! onomy, Hanover, NH 03755 ! ! Ship_Via: UPS ! UPS (2-day) or OVERNIGHT ! Overnight shipping done at PI expense Recipient_Email: ! Needed if Ship_To: is not PI_Address !