Is this melody part of the French church mass? In this article, in the section entitled The “Great” Aleinu History, the author writes that a particular melody used in Jewish High Holiday prayers was added to the French Church Mass in the late 12th century by French crusaders, and can be heard to this very day. You can directly play the mp3 here.

My question is, is it true that this melody can still be heard in the mass to this very day? What part of the mass is it used for? Are there any audio recordings of it?

EDIT:

Also, from the article linked in caseyr547's answer below:


  Another report adds that the Gentiles 'henceforth used the chant in their church,' and musicologist Eric Werner did in fact locate the melody in the Sanctus of the Ninth Mass of the Virgin.
I have recently taken few lesson of Gregorian Chant and we sung something from the Ninth Mass to Virgin Mary. Unfortunately, we stopped at Kyrie and I've heard its Sanctus just once or twice, so I can't tell whether some part of it is similar to that Aleinu record or not. I have notes for the Sanctus, so at the first opportunity I can scan the notes and link the picture, so that someone more competent can verify this theory. The guy who taught me the chant has been to France few times, so it should be what we are looking for, not "central-europian mutation" of the same chant. Unfortunately, I'm not really competent in reading (medieval) musical notation, so there might be some piece similar to this even though I didn't find any similarity.

Anyway, even if the two melodies were somewhat similar, still it is quite likely to be just an accident. There is limited (though big) set of possible melodies, and set of melodies used for sacral music is not-as-big. Provided there are some similarities between Jewish sacral music and Gregorian Chant, such occasional similarities are inevitable.

Such random similarities in music are often exaggerated by conspiracy theorist. In my nation (Czech) vague similarities between our and Irish folk music are often presented as a proof that we are more Celtic than Slavic, but I remember one of the proponents of this theory to admit that he have heard music from Tibet that sounded more similar to some kinds of Czech folk music than Irish music does.