The flights over Quincy appear to be a Cessna 182 (or more than one) using an EO/IR sensor.

http://www.boston.com/yourtown/news/quincy/2013/05/photos_prove_suspicious_ aircra.html

A rough outline of the flight path :

https://www.boston.com/yourtown/news/quincy/2013/05/low-flying_aircraft_causing_co.html

” . . . it passes my house in Wollaston, circles over Milton, Blue Hills, over Randolph, Holbrook and comes back to the same spot every eight minutes. ”

A map of the area :

http://docs.unh.edu/MA/blue48nw.jpg

Cessna modification for law enforcement agencies :

http://www.cessnaenforcer.com/

http://www.youtube.com/watch?&v=txsHT36vCmo

The sensor vendor :

http://www.policeaviationnews.com/acrobat/192panewsapril2012.pdf

“SkyIMD, Inc., provider of aerial imaging systems, has announced that Cessna Aircraft Company has selected the SkyFusion Pak system for the Cessna Enforcer. It provides law enforcement customers the ability to customise their new Cessna 172, 182 and 206 aircraft with the mission equipment they need for aerial surveillance and live video downlink.”

http://skyimd.com/skyfusionpak.html

The RKT Productions (whoever they are) fleet :

http://www.regosearch.com/aircraft/us/461AJ

http://www.regosearch.com/aircraft/us/323LP

http://www.regosearch.com/aircraft/us/906TM