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The OMI has enormous potential for detecting supernovae. The
more galaxies that are observed the higher the probability of
detection. With its 5 degrees² field of view and the ability
to go very deep, potentially several supernovae could be detected
every night! The OMI can survey over 182 degrees² in an 8
hour period to magnitude 24 (z’, s/n=3. FWHM=1.25”).
According to the Deep Range Survey (Babul & Ferguson 1996,
KPNO) there are over 50,000 galaxies per degree² at magnitude
24 visible outside the galactic plane. Thus OMI could potentially
detect 10,000,000 galaxies during an 8 hour period. Only supernovae
that reach the detection level can be observed! At magnitude 24
the supernovae will be much further out ( higher red shift) than
the brighter galaxies and thus should help in calibrating the
distance scale.
Supernova
Science with the OMI.pdf (181 KB)
The most successful supernovae search is the KAIT ( The Katzman
Automatic Imaging Telescope, Lick Obs.), which over the last 10
years has detected some 66 supernovae per year. The OMI has some
350X the field size and is able to image 2-3 magnitudes deeper
which would suggest that the OMI could detect hundreds if not
thousands of supernovae per year!
Limiting magnitude z’ = 22 (s/n=3)
Exposure = 37sec. (including 16 second download)
8 hour survey = 3,767degrees²
Galaxies per degrees² = 15,000 ( z’)
Potential total galaxies = 15,000 gal/deg² X 3,767 deg²=
~56,000,000
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Mag. z' s/n=3
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Exp. s
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Area deg²
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Galaxies/deg²*
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Galaxy count*
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21
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20
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6,969
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6,000
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40,000,000
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22
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37
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3,767
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15,000
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56,000,000
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23
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137
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1,017
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25,000
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35,000,000
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24
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764
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182
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55,000
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10,000,000
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Supernovae search potential based on total
galaxy count (FWHM=1.25”, 8 hr night, includes 16s
download time (* based KNPO 1997 data).
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OMI
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KAIT
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Aperture (m)
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1.0
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0.7
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Lim. Mag r' (30s)
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22.8
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19.5
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FOV deg²
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4.94
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0.013
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| Discoveries/year |
>25000
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66
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KAIT compared to OMI in terms of potential
discoveries per year. (KAIT = The Katzman Automatic Imaging
Telescope, Lick Obs.).
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Galaxy count deg²/mag, KPNO.
Next: Extra-Galactic Astronomy
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