GCN Circular 1608

K. Sahu, A. Fruchter, I. Burud, and K. Sembach (STScI) report for the
larger GOSH collaboration:

GRB 020411 was observed from 14:00 to 23:00 UT on Oct 6 using the STIS
CCD spectrograph and G430L grism, and the NUV MAMA and prism.   The 
CCD spectrum shows two prominent absorption features, at 404.1 nm and
401.1 nm.    The first of these agrees well with a previously reported
feature that has been identified as Lyman alpha at z=2.323.  The second
absorption feature would then appear to be Si III at z=2.324, which
would
imply an offset of order 100 km/s in the restframe between the ionized
and neutral components.  

The NUV MAMA prism observation shows a break shortward of approximately 
303.0 nm, which would correspond to the Lyman limit of the z=2.323
system.  
Calibration of both the CCD and NUV MAMA observations may be improved
when all files from the observation are available to us.