This is a substitute visit to replace the initial 3rd visit. The reason for this substitution is that
T Pyx is brighter than the expected, generic nova and thus we wish to take advantage of this by
expanding the wavelength coverage. The original proposal just had long exposures with the
E140M and E230M (1978) echelles. In this version we add an E230 (2707) echelle exposure and
short exposure with the the low resolution G430L CCD. These additions expand our coverage from
the original 2382 Angstroms out to 5700 Angstroms and allow us to view the important Mg II (2800)
and [Ne V] (3346, 3426) lines which are either impossible or difficult to get from the ground.----- Attempting Submission 1 (Sun Jul 17 15:17:54 GMT 2011) -----
----- Attempting Submission 2 (Thu Aug 25 19:20:15 GMT 2011) -----This is submission makes a few changes to the program for the 3rd visit of T Pyx. The
first change is that the observation window is finally set, between Sept 25 - Oct 8th.
The other change is the addition of other exposures to extend the coverage out to
5700 Angstroms. T Pyx is brighter than a the generic nova used in the initial proposal
and thus this version of the 3rd visit takes advantage of that fact.STIS UV spectroscopy of a bright classical nova during its super soft X-ray phaseWe propose ToO observations of a bright classical nova (CN) in outburst using the STIS echelle to obtain ultraviolet spectroscopy while the source is X-ray luminous. The data will complement our existing ground based optical/infrared and Swift X-ray CN programs and provide continous spectral information from X-ray to the IR during this important X-ray phase for the first time. The UV spectroscopy is a critical bandpass that enables determination of ejecta physical properties, including the elemental abundances, mass, and structure. This information provides insight into the role of CNe in the isotopic enrichment of the interstellar medium, pre-solar grain abundances, details on the mass and composition of the underlying white dwarf, needed checks on hydrodynamic models of the outburst, and constraints on the relationship of CNe as SN Ia progenitors. UV data are key to these analyses, providing the only opportunity to observe strong carbon lines in these objects as well as direct measures of the interstellar reddening. With slit spectroscopy from ~ 1100-3100 Angstroms, HST is currently the only facility that can fill this important gap in the spectral energy distribution.We will observe a bright nova during its super soft source (SSS) X-ray phase as determined by Swift XRT monitoring. The program calls for three separate one orbit visits. The initial ToO trigger occurs when the source enters the SSS phase, e.g., the majority of photons have E ~< 1 keV and a Swift X-ray count rate ~> 0.1 ct/s. The second visit is initiated after the source has reached X-ray maximum and stabilized at an approximately constant level. The last visit is scheduled after the decline in the X-ray light curve indicating that nuclear burning has ended. This will give us UV spectra of the ejecta exposed to different photoionization levels.
In order to sample the full spectral range we will use the E140M and E230M gratings. The echelle is necessary to provide high resolution data while also minimizing the flux on the MAMA detectors for this bright source. For each orbit we use the CCD and F28X50LP aperture to acquire the source. A 1 second exposure is sufficient to obtain enough S/N to acquire but if the source is too bright we will switch to the F20X50OII aperture. We will use the E140M and the E230M (lambda1978) to obtain the critical 1150-1700 Angstrom and 1600-2300 Angstrom spectra. In the first and second visits this will be supplmented with an additional E230M (lambda 2707) exposure to get the 2300-3100 Angstrom data. There will be no E230M (lambda 2707) during the third visit. The exposure times for each grating and position should be approximately equal in each visit, e.g. 360-590 seconds in visits 1 and 2 and longer 780-1050 second exposures in visit 3. The 0.2'' X 0.2'' slit will be used unless the nova is too bright in which case we will use an appropriate neutral density filter. This is unlikely as such novae are relatively rare. We will use visual photometry and Swift UVOT data to estimate the UV brightness before each visit to ensure the health of the MAMA detectors.This is a Target of Opportunity program and thus will be scheduled once the PI identifies an acceptable target. The program also utilizes the STIS MAMA detectors so the observations must be taken in non-SAA impacted orbits.HOT STARS12false0.00.0falsefalsefalsefalseSUPPORTEDSTARRECURRENT NOVAThis object was generated by the targetselector and retrieved from the SIMBAD database.TPYXJ2000J2000STIS/FUV-MAMASpectroscopicNoNoE140M1425STIS/NUV-MAMASpectroscopicNoNoE230M1978STIS/NUV-MAMASpectroscopicNoNoE230M2707STIS/FUV-MAMASpectroscopicNoNoE140M1425STIS/NUV-MAMASpectroscopicNoNoE230M1978STIS/NUV-MAMASpectroscopicNoNoE230M2707STIS/FUV-MAMASpectroscopicNoNoE140M1425STIS/NUV-MAMASpectroscopicNoNoE230M1978Timing link suitability includes constraints ([02 After 01 by 30.0 to 50.0 days] [99 After 01 by at least 60.0 days])The scheduling data was generated by CASM 18.3.1.CASM was run in Phase II mode.First observation before visual maximum. T Pyx has reached V ~ 7.5 mag.1304754374000103.04405891981281(Tic-Visit
:proposal-id 12200
:visit-id "01"
:proposal-version -1
:trans-version "20100505"
:date "24-Apr-2011 13:44:18.0"
:trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0
:FATAL-ERRORS 0 :CONTINUABLE-FATALS 0)
:number-of-orbits 1
:saa-model "24"
:si-bright-earth-limb-angle 20.0
:data-volume 261424
:tdrss-contact-duration 0
:coron NIL
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(Tic-Obset
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:obset-id "01"
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(Tic-Orbit
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:visit-id "01"
:orbit-number 1
:pcs-time 333
:si-vis-utilization 2940
:al-overhead-at-end 0
:internal-dur-at-end 396
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3275
:pcs-gap 0
)false10Timing link suitability includes constraints ([03 After 02 by 50.0 to 80.0 days])The scheduling data was generated by CASM 18.3.1.CASM was run in Phase II mode.Modified V2 for a brighter T Pyx than initially expected.(Tic-Visit
:proposal-id 12200
:visit-id "02"
:proposal-version -1
:trans-version "20100505"
:date "29-Jun-2011 10:23:35.0"
:trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0
:FATAL-ERRORS 0 :CONTINUABLE-FATALS 0)
:number-of-orbits 1
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:data-volume 261520
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(Tic-Obset
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:visit-id "02"
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:pcs-mode "FGS"
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(Tic-Orbit
:proposal-id 12200
:visit-id "02"
:orbit-number 1
:pcs-time 333
:si-vis-utilization 2942
:al-overhead-at-end 0
:internal-dur-at-end 396
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3275
:pcs-gap 0
)false10Timing link suitability includes constraints ([03 After 99 by 50.0 to 120.0 days])The scheduling data was generated by CASM 19.3.CASM was run in Phase II mode./private/var/folders/dW/dWEC5QrmHka4IkUmjGtKo++++TI/-Tmp-/OPVisit8222609940869903843.xmlTo be taken after the large decline from the optical "plateau" or pending an event in the X-ray, e.g. a unexpected rebrightening or final decline.(Tic-Visit
:proposal-id 12200
:visit-id "03"
:proposal-version -1
:trans-version "20110509"
:date "25-Aug-2011 15:06:19.0"
:trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0
:FATAL-ERRORS 0 :CONTINUABLE-FATALS 0)
:number-of-orbits 1
:saa-model "24"
:si-bright-earth-limb-angle 20.0
:data-volume 316624
:tdrss-contact-duration 0
:coron NIL
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(Tic-Obset
:proposal-id 12200
:visit-id "03"
:obset-id "03"
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(Tic-Orbit
:proposal-id 12200
:visit-id "03"
:orbit-number 1
:pcs-time 333
:si-vis-utilization 2942
:al-overhead-at-end 0
:internal-dur-at-end 415
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3275
:pcs-gap 0
)true10Target of Opportunity. Hold will be released when selected source fades from X-ray maximum as seen by Swift.Timing link suitability includes constraints ([03 After 99 by 50.0 to 120.0 days])The scheduling data was generated by CASM 19.3.CASM was run in Phase II mode.This is a substitute visit to replace the currently scheduled 2nd visit. The reason for this substitution is that T Pyx has undergone an unexpected dust formation event, the first in a recurrent nova. The formation of dust has cause the UV flux, as measured by Swift UVOT photometry, to plummet in the last few days. The decrease is sufficient to make parts of the current 2nd visit less than optimal, specifically the neutral density filter on the E230M (2707) exposure. If the second visit plan can be changed we would like to substitute this version to account for the significantly lower UV flux and include a few optical exposures since T Pyx can't currently be observed from the ground.1311878275000169.5816537183157(Tic-Visit
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:trans-version "20110509"
:date "17-Jul-2011 11:03:06.0"
:trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0
:FATAL-ERRORS 0 :CONTINUABLE-FATALS 0)
:number-of-orbits 1
:saa-model "24"
:si-bright-earth-limb-angle 20.0
:data-volume 427040
:tdrss-contact-duration 0
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:internal-dur-at-end 441
:dark-offset NIL
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:max-dark-utilization 1920
:low-sky "N"
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