LaTeX.org

When you do that the height of the symbol become too long according to the symbols that are in same font size, however thank you for your concern and answer.

I don't know. If I know, I would also probably find. I looked at comprehensive symbols book but I couldn't fully search it since it is too long.

I guess there is no such symbol. In that case, how can I write it on latex? I heard about creating new symbols in latex somewhere. How can I do this?

I made it with paint by arranging "I" and "\Uppsi". But of course it is now a picture, however I want to use it in equations. How can I write it in latex with latex commands?
Symbol:
http://img407.imageshack.us/img407/2998/psiupdown.png