title: High-accuracy differential image motion monitor measurements for the Thirty Meter Telescope site testing program.
abstract: Differential image motion monitors (DIMMs) have become the industry standard for astronomical site characterization. The calibration of DIMMs is generally considered to be routine, but we show that particular care must be paid to this issue if high-accuracy measurements are to be achieved. In a side by side comparison of several DIMMs, we demonstrate that with proper care we can achieve an agreement between the seeing measurements of two DIMMS operating under the same conditions to better than +/-0.02 arc sec.
authors.affiliation: Department of Physics and Astronomy, University of California, Irvine, Irvine, California 92697, USA. lianqiw@tmt.org
authors.forename: Lianqi
authors.initials: L
authors.lastname: Wang
authors.forename: Matthias
authors.initials: M
authors.lastname: Schöck
authors.forename: Gary
authors.initials: G
authors.lastname: Chanan
authors.forename: Warren
authors.initials: W
authors.lastname: Skidmore
authors.forename: Robert
authors.initials: R
authors.lastname: Blum
authors.forename: Edison
authors.initials: E
authors.lastname: Bustos
authors.forename: Sebastian
authors.initials: S
authors.lastname: Els
authors.forename: Reed
authors.initials: R
authors.lastname: Riddle
authors.forename: Juan
authors.initials: J
authors.lastname: Seguel
authors.forename: Tony
authors.initials: T
authors.lastname: Travouillon
authors.forename: Joselino
authors.initials: J
authors.lastname: Vasquez
authors.forename: David
authors.initials: D
authors.lastname: Walker
authors.forename: Paul
authors.initials: P
authors.lastname: Gillett