Only changes are ORIENT constraint on visit 5 and small reduction on integration time on Visit 6/Exposure 5 because it overran.----- Attempting Submission 2 (Fri Jul 01 18:36:20 GMT 2011) -----Debris Disk Chemistry from Spatially Resolved SpectroscopyWe propose the first coronagraphic spectroscopy of three circumstellar debris disks. These observations will enable the only possible studies of their cold dust grain compositions. Spectroscopy of their dust will provide detailed reflectivities from 3500 - 9500 Angstroms, an unprecedentedly large wavelength grasp. We will be able to estimate the organic-to-silicate ratio of the dust and constrain its place of formation and subsequent processing. Debris dust arises from the collisions and evaporation of planetesimals, and it is these same planetesimals which are the building blocks for planets. The compositions and dynamics of planetesimals may reflect and affect the final composition and architectures of the planetary systems.
All of our targets have been imaged previously with HST. All have complex broad-band colors that change with location in the disk and that may signal the presence of dynamical perturbations or compositional processing. We have demonstrated in a previous program how to use STIS for spatially resolved disk spectroscopy. We now propose to apply our technique to study the compositions of essentially all known edge-on disks bright enough to observe with STIS.Each target consists of a sequence of observations:
1. Standard acquisition
2. Peakup - We do the peakup in the smallest available aperture.
Then, for both G430L and G750L gratings, we do the following:
3. Point source spectrum outside of fiducial in 52x0.2 slit
4. Fiducial spectra - maximum integration time for bright sources set by time to saturation of stellar scattered light at edge of the fiducial, minimum integration time for faint sources set by time to achieve source noise limited spectra. Integrations are CR-SPLIT for CR removal. In Phase I, we specifically requested the F2 fiducial (unsupported aperture) because of its superior light rejection. For the science objects, we specify a narrow range of acceptable ORIENTs to position the slit along the disk major axis.
For G750L only, we do a
5. FlatPSF observation - This is necessary to be able to subtract off the stellar contribution at every position and wavelength to reveal the spectrum and spatial profile of the disk.
Peakup - though not strictly required according to the STIS IHB, we want exceptionally good positioning under the fiducial in order to be able to cleanly subtract off the PSF contribution. For all targets (objects and PSFs), we do the peakup in the smallest available aperture.
Point source spectrum outside of fiducial in 52x0.2 slit - This is necessary for calibrating out any spectral differences between the target and PSFas well as for aiding in photometric calibration
G750L flat -CCDFLAT taken with 52X0.2 slit for better defringing of extended-source spectra (narrower slit would be better for defringing point-source spectra).EXTRA-SOLAR PLANETS12false0.00.0falsefalsefalsefalseAVAILABLESTARA0-A3 V-IVHipparcos ICRS coordinates J1991.25J2000J2000STARA0-A3 V-IVHipparcos ICRS coordinates epoch 1991.25J2000J2000STARA0-A3 V-IVA0V star; B-V=0.2; Hipparcos ICRS coordinates epoch J2000 (via VizieR)J2000J2000STARA0-A3 V-IVB-V=0.2. Hipparcos ICRS coordinates epoch J1991.25HD31489J2000J2000STARM V-IVThis object was generated by the targetselector and retrieved from the SIMBAD database.
Hipparcos PMs and PlxJ2000J2000STARM V-IVThis object was generated by the targetselector and retrieved from the SIMBAD database.
PMs and Plx from HipparcosJ2000J2000STIS/CCDSpectroscopicNoNoG750L7751STIS/CCDSpectroscopicNoNoG430L4300STIS/CCDSpectroscopicNoNoG750L7751STIS/CCDSpectroscopicNoNoG430L4300STIS/CCDSpectroscopicNoNoG750L7751STIS/CCDSpectroscopicNoNoG430L4300STIS/CCDSpectroscopicNoNoG750L7751STIS/CCDSpectroscopicNoNoG430L4300STIS/CCDSpectroscopicNoNoG750L7751STIS/CCDSpectroscopicNoNoG750L7751Timing link suitability includes constraints ([Group (01 02) Within 0.2 days])The scheduling data was generated by CASM 19.3.CASM was run in Phase II mode./private/var/folders/x-/x-OPzCZ3HuarTIaDLTVAIk+++TI/-Tmp-/OPVisit3790664942845945730.xmlPoint-source and fiducial spectra of HR4796A with G705L and G430L. Need to align slit parallel to disk semi-major axis. Disk PA = 27.1 degrees. ORIENT = (27.1, 207.1) + offset angle = (27.1, 207.1) + 45 -1 = (71.1, 251.1) degrees. I would prefer exactly this angle, but at 1'', I could tolerate an offset of 1/4 of a slit width, which corresponds to an angular offset of +/- 1.5 degrees. This offset angle (-1 deg) comes from Don Lindler (actually -0.957 deg). Charles Proffitt will get back to me on additional offset angle due to rotation of the slit. It turns out that the PA=71 is the schedulable orientation. Visits 01 and 02 should be scheduled as close together in time as possible.(Tic-Visit
:proposal-id 12512
:visit-id "01"
:proposal-version -1
:trans-version "20110509"
:date "01-Jul-2011 14:35:54.0"
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(Tic-Obset
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(Tic-Orbit
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(Tic-Orbit
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:visit-id "01"
:orbit-number 2
:pcs-time 222
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:dark-offset NIL
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:low-sky "N"
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)true20HR 4796 is A0V with B=5.79, V=5.78. F28X50OII filter gives S/N = 132 in 0.1s and doesn't saturate (with F28X50LP, brightest pixel saturates in minimum exposure time).Peak-up in x and y required for accurate positioning of star under fiducial bar (short slit peak-up). T_exp = 0.1s with 0.2X0.05ND gives S/N = 159, with 14,363e- in brightest pixel (>5000e- desired according to STIS IHB).).4s gives S/N > 52 achieved at all wavelengths > 3100A.Brightest pixel (4000 Ang) in 891s = 891s x 17.6 counts/pix/s = 15682 = 48% full well at GAIN=1.
Maximum count rate estimated from 52X0.2F2 observation of HD141653 (A2V star, B=5.25, file o68m01050_crj.fits) and scaling to brightness of HR 4796A, B=5.79.0.4 s gives S/N > 52 for wave<9750A.CCDFLAT taken with 52X0.2 slit for better defringing of extended-source spectra (narrower slit would be better for defringing point-source spectra). Do 2 iterations for cosmic-ray rejection.Brightest pixel in 646s = 646s x 28.7 counts/pix/s = 18540 = 56% full well at GAIN=1.
Maximum count rate estimated from 52X0.2F2 observation of HD141653 (A2V star, V = 5.194, file o68m010b0_crj.fits) scaled to brightness of HR 4796A, V=5.78.Timing link suitability includes constraints ([Group (01 02) Within 0.2 days])The scheduling data was generated by CASM 19.3.CASM was run in Phase II mode./private/var/folders/x-/x-OPzCZ3HuarTIaDLTVAIk+++TI/-Tmp-/OPVisit6347840995272787400.xmlPoint-source and fiducial spectra of HR4748-PSF with G705L and G430L. No orientation constraint for observations. Visits 01 and 02 should be scheduled as close together as possible (GROUP WITHIN constraint given on visit 01).(Tic-Visit
:proposal-id 12512
:visit-id "02"
:proposal-version -1
:trans-version "20110509"
:date "01-Jul-2011 14:35:57.0"
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(Tic-Obset
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(Tic-Orbit
:proposal-id 12512
:visit-id "02"
:orbit-number 1
:pcs-time 333
:si-vis-utilization 2968
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:dark-offset NIL
:dark-utilization 0
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)true10B=5.382, V=5.448, B8V; F28X50OII filter gives S/N = 190 in 0.1s and doesn't saturate (with F28X50LP, brightest pixel saturates in minimum exposure time).Peak-up in x and y required for accurate positioning of star under fiducial bar (short slit peak-up). T_exp = 0.1s with 0.2X0.05ND gives S/N = 210 and does not saturate. 21,320e- in brightest pixel.S/N >75 achieved at all wavelengths > 3100A.PSF star is 0.41 mag = 1.46 times brighter than HR4796 at B.
Brightest pixel in 250s image = 250s x 25.7 counts/pix/s = 6425 e- = 19% full well at GAIN=1. No problems there.
Maximum count rate estimated from 52X0.2F2 observation of HD141653 (A2V star, B=5.25, file o68m01050_crj.fits) scaled to B=5.380.4 s gives S/N > 57 for wave<9750A.CCDFLAT taken with 52X0.2 slit for better defringing of extended-source spectra (narrower slit would be better for defringing point-source spectra). Do 2 iterations for cosmic-ray rejection.PSF star is 0.33 mag = 1.355 times brighter than HR4796.
Brightest pixel in 350s image = 350s x 38.9 counts/pix/s = 13615 = 41% full well at GAIN=1. No problem there.
Maximum count rate estimated from 52X0.2F2 observation of HD141653 (A0V star, V = 5.194, file o68m010b0_crj.fits) scaled to HR 4748 V=5.45.Timing link suitability includes constraints ([Group (03 04) Within 0.3 days])The scheduling data was generated by CASM 19.3.CASM was run in Phase II mode./private/var/folders/x-/x-OPzCZ3HuarTIaDLTVAIk+++TI/-Tmp-/OPVisit2298009328318588066.xmlPoint-source and fiducial spectra of HD 32297 with G705L and G430L. Need to align slit parallel to disk semi-major axis. Disk PA = 47.5/227.5 degrees (median of both lobes). ORIENT = (47.5, 227.5) + offset angle = (47.5, 227.5) + 45 -1 = (91.5, 271.5) degrees +/- 1.0 degrees. Charles Proffitt will get back to me on additional offset angle due to rotation of the slit, but -1 deg comes from Don Lindler. Visits 03 and 04 should be scheduled as close together in time as possible.(Tic-Visit
:proposal-id 12512
:visit-id "03"
:proposal-version -1
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(Tic-Obset
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(Tic-Orbit
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(Tic-Orbit
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:low-sky "N"
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(Tic-Orbit
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(Tic-Orbit
:proposal-id 12512
:visit-id "03"
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)true40F28X50OII filter (3729A) gives S/N = 75 in 0.3s and doesn't saturate (with F28X50LP, 70% full well in minimum exposure time; too close to saturation for comfort).
B=8.33
V=8.13Peak-up in x and y required for accurate positioning of star under fiducial bar (short slit peak-up). IHB says we need at least 5000e- (1250 DN). T_exp = 0.3s with 0.2X0.05ND gives S/N = 60 with 4453e- in brightest pixel and 17390e- in 32x32 box.Tint=1 s gives S/N > 30 at wavelengths > 3100A; SN>80 for wavelengths>3600.Brightest pixel in expects 1.7 e-/s at about 4000 Ang. Should be no problem with saturation at edge of fiducial.
Maximum count rate estimated from 52X0.2F2 observation of HD141653 (A0V star, B=5.25, file o68m01050_crj.fits) scaled to HD 32297 at B=8.33.2 s gives S/N>36 at wavelengths<9750ACCDFLAT taken with 52X0.2 slit for better defringing of extended-source spectra (narrower slit would be better for defringing point-source spectra). Do 2 iterations for cosmic-ray rejection.Brightest pixel will have 3.3e-/s, so can go as long as 10,000 s without saturating. Just fill orbits.
Maximum count rate estimated from 52X0.2F2 observation of HD141653 (A0V star, V = 5.194, file o68m010b0_crj.fits) scaled to V=8.13 of HD 32297.Timing link suitability includes constraints ([Group (03 04) Within 0.3 days])The scheduling data was generated by CASM 19.3.CASM was run in Phase II mode./private/var/folders/x-/x-OPzCZ3HuarTIaDLTVAIk+++TI/-Tmp-/OPVisit1629523423203411321.xmlPoint-source and fiducial spectra of HIP22984-CALIB for HD 32297 with G705L and G430L. No orientation constraint for observations. Visits 03 and 04 should be scheduled as close together as possible (GROUP WITHIN constraint given on visit 03).(Tic-Visit
:proposal-id 12512
:visit-id "04"
:proposal-version -1
:trans-version "20110509"
:date "01-Jul-2011 14:36:03.0"
:trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0
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:data-volume 221360
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(Tic-Obset
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:visit-id "04"
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)
(Tic-Orbit
:proposal-id 12512
:visit-id "04"
:orbit-number 1
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)true10B=7.68, V=7.49, B8V; 0.2 s in F28X50OII filter gives S/N = 73 (too bright for F28X50LP)Peak-up in x and y required for accurate positioning of star under fiducial bar (short slit peak-up). T_exp = 0.2s with 0.2X0.05ND gives S/N = 75 and 5709e- in brightest pixel.S/N > 35 achieved at all wavelengths > 3100A.PSF star is 0.64 mag brighter (1.8x brighter) than HD 32297.
Brightest pixel at edge of fiducial should have 2.8 e-/s. Not a problem for exposures < 10Ks.
Maximum count rate estimated from 52X0.2F2 observation of HD141653 (A0V star, B=5.25, file o68m01050_crj.fits) and scaled to HIP 22984 with B=7.691.8 s gives S/N > 50 for wave<9750A.CCDFLAT taken with 52X0.2 slit for better defringing of extended-source spectra (narrower slit would be better for defringing point-source spectra). Do 2 iterations for cosmic-ray rejection.PSF star is 0.64 mag brighter (1.8x brighter) than HD 32297.
Brightest pixel at edge of fiducial should have 5.9 e-/s. Not a problem for exposures < 5Ks.
Maximum count rate estimated from 52X0.2F2 observation of HD141653 (A0V star, V =5.19, file o68m01050_crj.fits) and scaled to HIP 22984 with V=7.49Timing link suitability includes constraints ([Group (05 06) Within 0.3 days])The scheduling data was generated by CASM 19.3.CASM was run in Phase II mode./Users/alycia/Documents/proposals/hst/cycle19/PhaseII/OP-cache/12512-v05.xmlPoint-source and fiducial spectra of AU Mic with G705L. Need to align slit parallel to disk semi-major axis. Disk PA = 128.6 degrees (Krist et al. 2005). ORIENT = (128.6, 308.6) + offset angle = (128.6, 308.6) + 45 -1 = (172.6, 352.6) degrees. Charles Proffitt will get back to me on additional offset angle due to rotation of the slit (see p. 269; 282 of PDF of IHB), but this one comes from Don Lindler and should be ok. Visits 05 and 06 should be scheduled as close together in time as possible.
The AU Mic midplane is narrow; at 1.9'' from the star, the FWHM of the midplane is 0.24'' (from Figure 6 of Krist et al. 2005). The maximum angle that can be tolerated at 2'' is 1/2 slit width, or 0.1''. This implies an angle asin(0.1)/2 = 2.9 deg. So, I could do 352.6+2.9 = 355.5 deg at absolute worst. At 3'' from the star, the angle is asin(0.1)/3 = 1.9 deg. For now, specify MaxOrient of orient+1 deg (i.e. 353.6) but could relax a little later if necessary for schedulability. MinOrient is not constraining the schedulability, so leave it.
To get desired ORIENT to schedule, I had to shorten my orbits by 1-2 min.(Tic-Visit
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(Tic-Obset
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(Tic-Orbit
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(Tic-Orbit
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(Tic-Orbit
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)true30B=10.05, V=8.61; Saturates in minimum exposure time in F28x50LP;
F28X50OII( filter gives S/N = 75 in 0.31s and doesn't saturate but might have flare emission (STIS.ta.179214)
Went with F25ND3; used successfully in program 12228
F25ND3 gives S/N=82 (2413 e- in brightest pixel) in 0.3 sPeak-up in x and y required for accurate positioning of star under fiducial bar (short slit peak-up). IHB says we need at least 5000e- (1250 DN). T_exp = 0.4s with 0.2X0.05ND gives S/N = 80 with 5188e- in brightest pixel and 23,785e- in 32x32 box.0.5 s gives S/N>58 at all wavelengthsCCDFLAT taken with 52X0.2 slit for better defringing of extended-source spectra (narrower slit would be better for defringing point-source spectra). Do 2 iterations for cosmic-ray rejection.Brightest pixel at edge of wedge from star will have 5.4e-/s, so can go as long as 6,000 s per exposure without saturating.
Maximum count rate estimated from 52X0.2F2 observation of CD-43 2742 (M20V star, V = 10.15) scaled to V=8.61 of AU Mic.
Make sure we're source noise dominated - for total expected disk+star surface brightness at 1'' of 3.5e-15 erg/s/cm^2/Ang/sq.arcsec, ETC says we get source noise=readout noise (15.8e-) for 330 s (See ETC STIS.sp.180489). For AU Mic disk alone, SB=1.2e-15. To get this to be source noise limited takes ~1000s. At R=2'', disk is 2x fainter. To get this to be source noise limited takes 1883 s. But, we need CR-SPLITs, so we'll do CR-SPLIT=2. In the firsts orbit, we only get ~790s/exposure. In subsequent orbits, we get 1400 s/exposure.
Note: I had to reduce the exposure time to 1500 s (which looks like it doesn't fill the orbit) in order to get my ORIENT schedulable -- i.e. move to a shorter orbit more off nominal.Timing link suitability includes constraints ([Group (05 06) Within 0.3 days])The scheduling data was generated by CASM 19.3.CASM was run in Phase II mode./Users/alycia/Documents/proposals/hst/cycle19/PhaseII/OP-cache/12512-v06.xmlPoint-source and fiducial spectra of GJ 784 with G705L. Visits 05 and 06 should be scheduled as close together in time as possible. This constraint is placed on Visit 5(Tic-Visit
:proposal-id 12512
:visit-id "06"
:proposal-version -1
:trans-version "20110509"
:date "01-Jul-2011 13:49:20.0"
:trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0
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:number-of-orbits 1
:saa-model "24"
:si-bright-earth-limb-angle 20.0
:data-volume 129328
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:coron NIL
)
(Tic-Obset
:proposal-id 12512
:visit-id "06"
:obset-id "06"
:pcs-mode "FGS"
)
(Tic-Orbit
:proposal-id 12512
:visit-id "06"
:orbit-number 1
:pcs-time 333
:si-vis-utilization 3057
:al-overhead-at-end 0
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:dark-offset NIL
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)true10B=9.42, V=7.97; Saturates in minimum exposure time in F28x50LP;
use same Acq filter as for AU Mic - F25ND3 gives S/N=81 in 0.2 sPeak-up in x and y required for accurate positioning of star under fiducial bar (short slit peak-up). IHB says we need at least 5000e- (1250 DN). T_exp = 0.2s with 0.2X0.05ND gives S/N = 65 with 4237e- in brightest pixel and 19039e- in 32x32 box.0.4 s gives S/N>60 at all wavelengthsCCDFLAT taken with 52X0.2 slit for better defringing of extended-source spectra (narrower slit would be better for defringing point-source spectra). Do 2 iterations for cosmic-ray rejection.Brightest pixel will have 9.7e-/s, so can go as long as 3000 s per exposure without saturating.
Maximum count rate estimated from 52X0.2F2 observation of CD-43 2742 (M20V star, V = 10.15) scaled to V=7.97 of AU Mic.