Re: A question came up from Bill J., while working on our TOO...

From: Rachel A. Gibbons (ragibbons@lbl.gov)
Date: Tue Jul 13 2004 - 09:12:56 PDT

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    Hi Bill,

        I responded to you on this point (and others) already asking about the
    possibility of moving those visits by a couple of days (earlier or later
    -- although earlier is probably not available to us) in order to improve
    the time of visibility.

        I'll also consider how our SNR would be affected if moving the BETWEEN
    doesn't help lengthen target visibility.

    Thanks,

    Rachel

    On Tue, 13 Jul 2004, Saul Perlmutter wrote:

    > A question came up from Bill J., while working on our TOO... He said
    > that in previous requests from Adam's team they found that they needed
    > to up the default earth-avoidance angle from 20 degrees to 25 degrees,
    > because they were getting too much noise. However, this would greatly
    > reduce the time we could get on our target per orbit, from almost 60
    > minutes to closer to 40 minutes. So the obvious question is whether
    > the extra noise is worse than the loss of exposure time in terms of
    > final signal-to-noise. Bill didn't know the numbers, and said that he
    > only knows of Adam needing to change this avoidance angle for his
    > program. So I will try phoning Adam now to see if he knows where the
    > trade-off occurs in terms of time loss.
    >
    > Rachel, are you still logged in (awake), if Bill needs new modified
    > instructions to fit a shorter orbit?

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