Optical Turbulence Measurements and Models for Mount John University Observatory

Details Optical Turbulence Measurements and Models for Mount John University Observatory Optical Turbulence Measurements and Models for Mount John University Observatory

2010-08-04

arxiv.org/abs/1008.0998v1

(2010) Pub. Astr. Soc. Australia 27(3): 347- 359

Astronomy and Astrophysics

Astrophysics

Instrumentation and Methods for Astrophysics

14 pages; accepted for publication in PASA

Scientific paper

10.1071/AS10008

Site measurements were collected at Mount John University Observatory in 2005 and 2007 using a purpose-built scintillation detection and ranging system. $C_n^2(h)$ profiling indicates a weak layer located at 12 - 14 km above sea level and strong low altitude turbulence extending up to 5 km. During calm weather conditions, an additional layer was detected at 6 - 8 km above sea level. $V(h)$ profiling suggests that tropopause layer velocities are nominally 12 - 30 m/s, and near-ground velocities range between 2 -- 20 m/s, dependent on weather. Little seasonal variation was detected in either $C_n^2(h)$ and $V(h)$ profiles. The average coherence length, $r_0$, was found to be $7 \pm 1$ cm for the full profile at a wavelength of 589 nm. The average isoplanatic angle, $\theta_0$, was $1.0 \pm 0.1$ arcsec. The mean turbulence altitude, $\bar{h_0}$, was found to be $2.0\pm0.7$ km above sea level. No average in the Greenwood frequency, $f_G$, could be established due to the gaps present in the \vw\s profiles obtained. A modified Hufnagel-Valley model was developed to describe the $C_n^2(h)$ profiles at Mount John, which estimates $r_0$ at 6 cm and $\theta_0$ at 0.9 arcsec. A series of $V(h)$ models were developed, based on the Greenwood wind model with an additional peak located at low altitudes. Using the $C_n^2(h)$ model and the suggested $V(h)$ model for moderate ground wind speeds, $f_G$ is estimated at 79 Hz.

Affiliated with

Also associated with

No associations

Rating

Optical Turbulence Measurements and Models for Mount John University Observatory does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Optical Turbulence Measurements and Models for Mount John University Observatory, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical Turbulence Measurements and Models for Mount John University Observatory will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-83353