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Re: xrt_co: - Draft proposal
That is ~ 1 to 2 CCD pixels per day. This might be do-able with good
statistics, I think.
--Mark
On Aug 20, 2008, at 4:14 PM, Leon Golub wrote:
> Sorry, I actually used 15 m/sec in the calculation; I just mistyped
> it in my message. The motion is ~15 m/sec X 86,000 sec per day, so
> it's 15X86 km = 1290 km per day.
>
>
>
> Ed Deluca wrote:
>> The meridional circulation is ~15m/s not 15km/s!!
>> This is going to be hard to see.
>> Ed
>> On Aug 20, 2008, at 4:01 PM, Leon Golub wrote:
>>> Ed
>>>
>>> OK, our visitor has given me his A&A paper, so this is a follow-
>>> up on my previous message. (Sorry about sending that to
>>> everybody; I hit the wrong button.) Again, I would think that you
>>> should stay away from the 7-day lifetime regions, even though
>>> they may not rotate with a different differential coefficient.
>>> They will, however, become fairly large, so that defining their
>>> location might become difficult.
>>>
>>> So, what can you do with one-day lifetime regions? At a speed of
>>> 15 km/sec, the latitudinal motion will amount to about 1300 km
>>> per day. That's about 2 arcsec, and I think is probably about
>>> equal to the best you could expect in terms of locating a central
>>> position for each XBP.
>>> That's not so terrible if you measure, say, 100 of them and
>>> figure that the statistics go as N^1/2. I'd say you have a chance
>>> of succeeding.
>>>
>>>
>>> By the way, you will only have a few 1-day regions regions each
>>> day. If you go for 2-day regions (might as well, while you're at
>>> it) there won't be many of them.
>>>
>>> Leon
>>>
>>>
>>> Ed Deluca wrote:
>>>> Attached is a draft proposal for a set of observations designed
>>>> to measure the
>>>> meridional circulation from XBPs. It is a difficult and time
>>>> consuming task,
>>>> so please review and comment on the feasibility and science
>>>> value. If
>>>> we think this is worthwhile I will present it to the SSC in
>>>> September.
>>>> Ed
>>>> -------------------------------------------------------------------
>>>> -----
>>>> ===================================================================
>>>> Dr. Edward E. DeLuca Smithsonian Astrophysical
>>>> Observatory
>>>> edeluca@cfa.harvard.edu MS 58
>>>> Office 617 496 7725 60 Garden Street
>>>> Fax 617 496 7577 Cambridge, MA 02138
>>>> Cell 508 728 5424 USA
>>>> ===================================================================
>>>
>>> --
>>>
>>>
>>> ***********************************************************
>>> Dr. Leon Golub; Harvard-Smithsonian Center for Astrophysics
>>> 60 Garden Street, Cambridge MA 02138
>>> Ph: 617 495 7177; Fax: 617 496 7577
>>> e-mail: lgolub@cfa.harvard.edu
>>> http://hea-www.harvard.edu/~golub/HomePage.html
>>> ***********************************************************
>
> --
>
>
> ***********************************************************
> Dr. Leon Golub; Harvard-Smithsonian Center for Astrophysics
> 60 Garden Street, Cambridge MA 02138
> Ph: 617 495 7177; Fax: 617 496 7577
> e-mail: lgolub@cfa.harvard.edu
> http://hea-www.harvard.edu/~golub/HomePage.html
> ***********************************************************