Keyword field with tabs in Solr 7.4

[Michael Aleythe, Sternwald]

Hey everybody,

i have a Solr field keyword field defined as:

<fieldType name="text_keyword" class="solr.TextField">
             <analyzer>
                           <tokenizer class="solr.KeywordTokenizerFactory" />
             </analyzer>
</fieldType>

<dynamicField name="*_KY" type="text_keyword"              indexed="true" 
stored="true"             termVectors="false" multiValued="false" />

Some documents have tabs (\t) indexed in this field, e.g. 
IPTC_2_080_KY:"\tbus\tbahn"

How can i query this content? I tried  "\tbus\tbahn", 
\\tbus\\tbahn<file://tbus/tbahn> and " bus bahn" but nothing matches. Does 
anybody know what to do?

Regards
Michael