Monacelli, The Martyrdom of St. Barbara
Church of Santa Barbara dei Librari, Rome
This fresco is probably from the 17th century. It sits just above Garzi's 17th-century painting of the saint's being welcomed into Heaven. The style of Barbara's garments would be consistent with this dating.
In the background is the tower that serves as St. Barbara's attribute in portraits.
Monacelli's name is given by an internet source; I have not found any information on an artist of such a name.
More of Saint Barbara
Photographed at the church by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license.