Description

Page : 1090

Sondrestrom Lidar Operation Log

Operator(s) : E.Guðmundsson
Purpose : Caracterization of chopper and polarization extinction tests.
Date(s) : 021127 - 021128
File(s) : L20021127_000 - L20021127_001
Comments : Started out by not having full signal due to iris clipping. Worked on that until I
got
3% or less loss of signal with minimum iris opening. Moved on to chopper
characterization. Moving the chopper changed the chopper slopes to the better
on
the low altitude side but got worse on the top side. Looks like the best chopper
location is where it is. Ran out of clear skies to confiirm this!
Logfile : L0211270.log

Setup:0

Page : 1091
[Variables]
Dye Power=85mJ
Rayleigh Power=450mJ

[0]
Iris=min_opening
Rayleigh System=On
Dye System=On
Etalon=Out
Daystar=Out
Polarizer=In
HalfWave Plates=Tracking
Rayleigh Filter=2:532(.5nm)
Rayleigh seeding=off

Logsheet:0

Page : 1092

Sondrestrom Lidar Operation Log

Log Sheet 1 of 2
Operators : E.Guðmundsson
Date(s) : 021127 - 021127
File(s) : L20021127_000 - L20021127_000

Files	Time [UT]	Comments	Cnt	S	Ope
L20021127_000	21:16:51	Start of experiment	889	0	EG
L20021127_000	21:25:17	Looks like thre is a small sporadic peek in the sodium at	878	0	EG
		92km.
L20021127_000	21:27:32	I think that the iris is blocking a bit of signal, open	890	0	EG
		iris a tad to see if counts change. counts data at 40km
L20021127_000	21:29:53	Have opened the iris a tad to see if counts increase.	933	0	EG
L20021127_000	21:31:18	No doubt, the iris is clipping. Counts	1085	0	EG
L20021127_000	21:33:43	Signal increase observed on both channels after opeing up	1097	0	EG
		the IRIS.
L20021127_000	22:07:50	Getting reference counts with chopper open fully	1062	0	EG
L20021127_000	22:11:05	No change counts with iris fully open:	1039	0	EG
L20021127_000	22:11:33	Closing iris down and working with iris.	1039	0	EG
L20021127_000	22:42:31	Just can't seem to gett the full counts with the iris at min!	1026	0	EG
		is very sensitive.
L20021127_000	23:04:17	Loose about 10% of the counts when closing iris fully.	901	0	EG
L20021127_000	23:06:04	Trying convergence again		0	EG
L20021127_000	23:07:24	did get some improvement, loosing about 3% now	973	0	EG
L20021127_000	23:08:16	Counts	975	0	EG
L20021127_000	23:08:32	This is the best I can do! Moving on to the chopper location	974	0	EG
		finding the best focal point of the chopper relay by phsyically
		moving the chopper.
L20021127_000	23:16:06	Chopper moved ~1mm "to the left"	928	0	EG
L20021127_000	23:19:59	Moving chopper 1mm to the left	881	0	EG
L20021127_000	23:21:03	@#!#$!%$!$% clouds! still have useful signal to do the chopper	358	0	EG

Logsheet:1

Page : 1093

Sondrestrom Lidar Operation Log

Log Sheet 2 of 2
Operators : E.Guðmundsson
Date(s) : 021127 - 021128
File(s) : L20021127_000 - L20021127_001

Files	Time [UT]	Comments	Cnt	S	Ope
L20021127_000	23:25:49	Moving chopper 1mm to the left.	764	0	EG
L20021127_000	23:33:00	Moving chopper 1mm to the left	725	0	EG
L20021127_000	23:42:44	It's difficult to say using the raw count profile only. the	583	0	EG
		Lower slope seems to gett better but the "top of the hill"
		seems to broaden out. I'm wondering about the time
		range dpendant nature of the focal plane. How far out do
		we have to get before we can say that we have source at
		infinity? Am I just optimizing for the fastest slope at the
		lower altitude, getting out of focus for the higher stuff?
L20021127_001	23:48:35	raising chopper to 60km and repeating the test!		0	EG
L20021127_001	23:50:06	Moving chopper to the start position.		0	EG
L20021127_001	23:55:41	reduced chopper delay by 100us, moving the chopper 15km	246	0	EG
		up.
L20021127_001	00:18:53	to coudy now shutting down	66	0	EG
L20021127_001	00:22:20	End of experiment	82	0	EG