Sequel to my rant on the so-called "Gathering Rite".
Here we have the so-called "sending forth song" or sometimes simply called the "sending hymn". Many confuse this for the recessional hymn, which is not part of the Mass but many of us sing it anyways. I can't say there is no such thing as a "sending rite". There is. It's actually called the "Dismissal rite". But here are the choices given for the REAL sending forth song (Celebrant's part in regular print, people's part in bold):
This is the simple Latin Ite, Missa Est, used in most Latin Novus Ordo Masses. Other settings, much more complex than the one above, can be found in the Kyriale.
Here is the chant setting in English, as found in the English version of the Roman Missal, often called the Sacramentary, a title that Rome has asked the USCCB several times NOT to use.
Finally, the Easter setting, in both Latin and English. This is the setting that is sung at the Easter Vigil, Easter Day, and through the Octave (Second/Low/Divine Mercy Sunday). It also appears in Mass I of the Kyriale.
So, there you have it, folks. These ARE the OFFICIAL "sending forth" songs. This is the OFFICIAL end of Holy Mass. Don't let the "music issues" dope slap you on the way out the door (ha ha ha).