Keck laser return and model Milonni,99 comparable with Na layer abundance from Maui LIDAR

1
Keck laser return and model (Milonni,99)
comparable with Na layer abundance from Maui
LIDAR

• Keck Laser
• 23 observations
• (May-June 2006)
• Milonni et al. (JOSA A 1999)
• Maui MALT
• 35 nights
• 979 data points
• (2002-2005)

Keck Laser median 2.47x10-9 atoms cm-2 Maui MALT
median 3.60x10-9 atoms cm-2
http//conrad.csl.uiuc.edu/Research/Maui/NaLidar/i
ndex.html
2
Modified LIDAR equation from Milonni et al.

• Anchored to LLNL dye laser data
• The flux at the telescope pupil in photons cm-2
  sec-1 is given by,

Keck Laser median 2.47x10-9 atoms cm-2 Maui MALT
median 3.60x10-9 atoms cm-2
where Plaser is the average output laser power,
tp is the laser pulse length, Rp is the pulse
repetition rate, Isat 5W/cm2 is the saturation
intensity for pulsed lasers, A 1/(16ns) is the
radiative decay rate for sodium atoms, a is the
spot FWHM at the sodium layer, z is the range to
the sodium layer from the telescope, Cs is the
sodium column density in atoms cm-2, Tatmos is
the atmospheric transmission Tbeam is the beam
train transmission.