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==> In this proposal, more time is being requested for MMORRIS.GCSHOCK
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Molecular gas within a few hundred parsecs of the Galactic center
displays considerable non-circular motion, perhaps as a response of the
gas to a central bar potential, or as a result of one or more violent
releases of energy in the past.  The tumult characterizing molecular
cloud kinematics there is accompanied by strong shock interactions
between clouds, or between clouds and the ambient medium. In the
Galactic Center,  shocks occur under very different conditions than
encountered normally (large size, extreme velocities, large magnetic
fields).  To investigate shocks occuring under these conditions,
and to compare with `standard' shocks as well as shock models,
we have used the LWS and SWS to observe a wide range of shock lines
in two regions in the Galactic Center (project MMORRIS.GCSHOCK).
In the current proposal, we request discretionary time to follow up
an intriguing result from the previous proposal.  We propose to extend
MMORRIS/GCSHOCK by carrying out an LWS F-P (LWS03) observation of a
0.6-micron range around the 179.5-micron water line for one of these
sources, G-0.02-0.07, a key object at the interface of a molecular
cloud and the nonthermal shell source Sgr A East. Our previous LWS
grating mode observation of this region showed a prominent absorption
feature near this wavelength; however, our previous F-P (LWS04) data,
which covered a 400 km/s velocity range, showed no evidence for the
179.5 micron water line. Thus either the identification of the
absorption line seen in the grating data as 179.5-micron H2O is
incorrect, or the line is very broad (>400 km/s).  Either possibility
is surprising.  Thus we are requesting additional time to observe a
wider wavelength range, to search for lines beyond our original F-P
range, or a very broad 179.5-micron line.