ASTRO-E News no 5: Bug in "Maki"

["Koji Mukai, US ASCA/ASTRO-E GOF, 301-286-9447" <MUKAI@lheavx.gsfc.nasa.gov>]

We have discovered a serious bug in Maki, the web-based tool to
display ASTRO-E field of view for a given roll angle, and to
investigate when a given roll is available.

The bug (which has been fixed as of 9am EDT, Wednesday, September
15th, at HEASARC)  was in the latter.  (The former --- the relationship
between the numerical values of the roll angle and how the field of
view overlays on Sky images --- was fine.)  Thus, for any given date,
Maki returned a 'legal roll angle' that was 90 degrees off from what
it should really be; integrated over a year, Maki was often claiming
impossible roll angle to be possible, and vice versa.

	This may be important to your proposals only if a specific
	and narrow range of roll angles is essential to your scientific
	objectives.

The new command-line tool, kappa, is not (and has never been) affected
by this bug.

Users do not have to download a new Plugin to correct this bug; the fix
is in place on in Skyview and in the web Stand-Alone version of Maki.
So you will get correct results the next time you use the HEASARC web
tools pages.  However, advanced users who downloaded the source code
(Maki.tcl) to run off the network are advised to download Maki.tcl again.

As a quick rule of thumb, the long axis of the XRS field of view must
point to the Sun.  Given the definition of roll angles (0 if long axis
is along the North-South line), the allowed range of roll angle is
typically near 60-120 and 240-300 at low ecliptic latitude.

We sincerely apologize for this bug, and for not having discovered it sooner.

There is another problem which affects OSF (DEC UNIX) users only.  There
was a bug in the LHEATcl plugin which caused MAKI to report *all* times
and roll angles as allowed or *all* times and rolls as not allowed.  This
is a separate problem for the roll offset problem described above.  If you
downloaded the LHEATcl plugin for OSF before September 15, you need to
download and install it again.

	http://heasarc.gsfc.nasa.gov/Tools/maki/plugin/

If you ran MAKI before September 15, and you are rechecking your results,
you may need to clear your browser's "cache" to enable the new version of
MAKI to download.  We have observed this problem only under Windows but
it may exist for other platforms.  To clear your cache:

- in Netscape: open the Edit->Preferences...->Advanced->Cache menu
  and click the two "Clear Cache" buttons.
- in IE:  open the Tools->Internet Options menu and on the General
  tab, click the "Delete Files..." button in the Temporary Internet Files
  section.  Check "Delete all offline content" and click OK.

* * *

If you have already submitted a roll-critical proposal, please contact
ISAS, GSFC, or ESA as appropriate.

If you are about to submit a roll-critical proposal, please re-check
your roll angle requirement.  If you do not think you can rework your
proposal in time for the deadline, please contact the appropriate
agency.

We will make every effort to ensure that affected proposers will not
be unnecessarily penalized by the bugs.

We again apologize for this mistake, and any inconveniences this may
have caused.