What is the Aramaic transliteration system used in the “Aramaic of Jesus” Wikipedia article?

Question

The Wikipedia article "Aramaic of Jesus" contains many instances of transliterated Aramaic, using a system I have not seen before. Some of the notations are well-established, like ŝ for /ʃ/ and macrons for long vowels, but there are many I haven't seen before.

I tried looking up more information on Aramaic transcription systems. Wikipedia has no article on Aramaic transcription, and the articles on Aramaic, Romanization of Hebrew, and various Hebrew letters don't seem to have any relevant information.

Particularly

T-cedilla:

• ţlīthā, ţlē

B-underline (the Wikipedia page used an actual underline; I added an underline diacritic since Markdown doesn't allow underline):

• Ţb̲îthâ, šəb̲aqtanî

Circumflex vowels:

• šəb̲aqtanî, bar-Yêšû`, tômâ

Spacing grave accent:

• Šim`ôn bar-Yônâ, bar-Yêšû`, r`am

g-breve ğ (I'm guessing this is supposed to represent /ɣ/, similar to its use in Turkish/Azeri.):

• rğaš

What transliteration system is this?

Answer 1

The t-cedilla indicates ט (tet).

The b-underline indicates an aspirated ב (bet; sounding similar to v).

Circumflex vowels indicate long vowels.

The grave accent on its own indicates ע (ayin).

The g-breve indicates an aspirated ג (gamal; sounding similar to "gh").

It's one of many variations that Semiticists use to express Aramaic, Hebrew, and other Semitic languages in transliteration. The actual symbols and Unicode combinations used may vary, but their meanings are generally understood and there is no one generally "recognized" or "authoritative" system and different publications use their own flavors (even in academic works). :-)