  Cornell's electron/positron storage ring (CESR) was modified over a series of
accelerator shutdowns beginning in May 2008, which substantially improves its
capability for research and development for particle accelerators. CESR's
energy span from 1.8 to 5.6 GeV with both electrons and positrons makes it
ideal for the study of a wide spectrum of accelerator physics issues and
instrumentation related to present light sources and future lepton damping
rings. Additionally a number of these are also relevant for the beam physics of
proton accelerators. This paper is the third in a series of four describing the
the conversion of CESR to the test accelerator, CesrTA. The first two papers
discuss the overall plan for the conversion of the storage ring to an
instrument capable of studying advanced accelerator physics issues and the
details of the vacuum system upgrades. This paper focusses on the necessary
development of new instrumentation, situated in four dedicated experimental
regions, capable of studying such phenomena as electron clouds (ECs) and
methods to mitigate EC effects. The fourth paper in this series describes the
vacuum system modifications of the superconducting wigglers to accommodate the
diagnostic instrumentation for the study of EC behavior within wigglers. While
the initial studies of CesrTA focussed on questions related to the
International Linear Collider damping ring design, CesrTA is a very versatile
storage ring, capable of studying a wide range of accelerator physics and
instrumentation questions.
