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   PR # 42152
   We propose to observe with ASCA three quasars (PKS2251+113, PHL909,
   and PG0043+039 ) in which we expect to detect ionized ("warm")
   absorbers. All the three objects show evidence of absorption in their
   ultraviolet spectra. The EINSTEIN spectra of the two (PKS2251+113 and
   PHL909) are consistent with having excess absorption at the source,
   while PG0043+039 has never been observed in X-rays. The constraints
   provided by both the X-ray and UV data will provide a powerful tool
   to study the physical, conditions in the absorbing gas.
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