“…When n = 0, as explained in [KP19, Remark 5.14], the stack J g,0 (φ can ) is isomorphic to Caporaso's universal compactified Jacobian [Cap94,Cap08], which is studied in detail in [Mel09], [BFV12], [BMV12], [MV14], [BMV12], [BFMV14], [CMKV15], [CMKV17] and is, in turn, isomorphic to Pandharipande's universal compactified Jacobian [Pan96] (see [EP16]). Note that in this case φ can is general precisely when d − g + 1 and 2g − 2 are coprime (see [Cap94,Proposition 6.2] and [KP19, Remark 5.12]).…”