Measurements and scalings of the H-mode pedestal on Alcator C-Mod

In this paper we summarize the results of recent measurements of the high c onfinement mode (H-mode) edge transport barrier in Alcator C-Mod. A number of new, high-resolution edge diagnostics provide measurements of plasma par ameters (electron density and temperature, and impurity density) in the ped estal region. Pedestal parameters are measured both at the top edge of the plasma and at the midplane. Very narrow (2-5 mm) electron density and tempe rature and impurity density pedestals are observed. The impurity pedestal i s located inside the density and temperature pedestals in the midplane meas urements, bur coincides with the n(e) pedestal at the top edge. Correlation of both width and height of the pedestals at the midplane with global plas ma parameters and core confinement characteristics is observed. At the same time there are no clear indications of scaling for the electron density an d impurity pedestal widths measured at the top of the plasma.