Question ID = 0100
Question ID = 0100
Assigned Member (担当者)2008-06-20 M.SuzukiName and Institute (質問者/機関)Dr. Alex Markowitz (UCSD)Question (質問)For both of the observations that I'm currently analyzing (ae702040010, observed Dec. 2007, and ae701033010, observed June 2006), I've noticed that the GTI extension list in each of the "tuned" v.2.0 PIN background event files are much smaller than those in the "quick" background files (many fewer rows for the tuned background). Furthermore, after forming a GTI file by ANDing the GTI extensions of the source event file and the tuned-background even file, applying this GTI when extracting source events for obsid 701033010 has no effect (i.e., the number of events extracted is the same regardless of whether the GTI is applied or not. This did not happen for the quick-look background.) Is there some extra filtering required for the "tuned" backgrounds that were not needed for the "quick-look" backgrounds? The impression I got from the web pages was that this was not the case. In the meantime, can the GTI formed from ANDing the GTI extensions of the quick-look background and source event files be used instead when extracting the source and tuned-background spectra? Answer from(回答の文責)Suzaku Help DeskAnswer (答え)
(1) GTI list of tuned background is shorter than that
of quick background.
There is nothing wrong with short GTI list of tuned
background. Since the processes of making quick and tuned
background differ from each other, the GTI lists could be
differ from each other.
(2) The number of selected events did not change whether
ANDing GTI of source and tuned background or not.
We checked the data of 701033010 and found that the GTI of tuned
background completely contains that of source events.
This is the reason the number of selected events did not change.
(3) Is there some extra filtering required for the "tuned" backgrounds
that were not needed for the "quick-look" backgrounds?
No. You can find a comment from HXD team in the web page:
http://www.astro.isas.jaxa.jp/suzaku/analysis/hxd/pinnxb/tuned/
"Please note that this new PIN-NXB files are also "*dead-time
corrected*", and hence the analysis procedure is exactly the same
between "quick" and "tuned"."
(4) Can the GTI formed from ANDing the GTI extensions of the quick-look
background and source event files be used instead when extracting
the source and tuned-background spectra?
No. The tuned backgrounds must be processed with its own GTIs,
because the processes of making tuned background is different
from that of quick background.
Status （詳細なステータス）2008-06-20 Accept2008-06-24 Done 
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