1) Our strategy is to have a combination of slot and slit observations, with the wide slot to maximize the likelihood of capturing the comet and slit rasters/sit-n-stare to obtain spectroscopic diagnostics.
We would like to run the following studies in a sequence:
1.1) 10:37-11:07 UT, on 2024-Oct-28 #91 Alignment_266: sit-and-stare wide slot (266"x512") including He II 256A.
1.2) 11:07-12:27 UT (-40 minutes before perihelion to +40 minutes after, covering 80 minutes) #557 HPW023_FULLCCD_V3s2 : Sit-and-stare with 2" slit (100s exposures). ~20 minutes duration for each pointing, to be optimized after considering slew time from one pointing to another (The 20 duration is based on the lifetime of bright tail striations of Comet Lovejoy)
1.3) 12:27-13:47 #403 Atlas_30 or #404 Atlas_60 raster scan: 30-60 min full CCD spectra with 2" slit (60"x160").
2) The exact pointing and timing will be communicated to the CO by the proposers before the Hinode draft plan is built.
3) There are a number of spectral lines of interest: Oxygen lines (from cometary water ice among other volatile material): O VI (171 A), O V (193), O III (263), and O IV (279). Fe VIII, Fe IX, Si VII, and Si VIII may also be observable. Ne III line at 251.14A: would be interesting, as it could potentially be the first confirmed detection, relevant to cometary formation models. |
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