Description

Page : 1805

Sondrestrom Lidar Operation Log

Operator(s) : Christian Have Pedersen
Purpose : Daytime background reference measurements on rayleigh channel. IR channel test and usual data acquisition on rayleigh and sodium channel.
Date(s) : 070216 - 070217
File(s) : L20070216_000 - L20070217_002
Comments : Started the experiment early to do daytime background reference measurements.
So there is a 2 and a half hour break in this experiment. IR measurements were
taken as well, but they were saturated by the nearfield ligth contamination.
RX half wave plate has been turned off for a while, due to emc. However, it was
not aligned with the TX HWP and this has been corrected, resulting in a marginal
improvement of 532 and 589 returns (counts).
Logfile : l1702070.log

Setup:0

Page : 1806
[0]
front end Iris=1.5mm
Rayleigh System=On
Rayleigh Field stop=0.5mm
Rayleigh path attenuation=0dB
Dye System=On
Sodium Field stop=0.5mm
Etalon=Out
Daystar=Out
Polarizer=In
HalfWave Plates=Out
Rayleigh Filter=2:532(.5nm)
Rayleigh seeding=off

Logsheet:0

Page : 1807

Sondrestrom Lidar Operation Log

Log Sheet 1 of 2
Operators : Christian Have Pedersen
Date(s) : 070216 - 070216
File(s) : L20070216_000 - L20070216_000

Files	Time [UT]	Comments	Cnt	S	Ope
L20070216_000	17:54:23	Start of experiment	0	0	cp
L20070216_000	17:56:26	PMT unblocked. Lasers are off. Chopper is in. Frontend and		0	cp
		receiver iris are partly open (Nearfield reducing)
L20070216_000	17:58:17	PMT unblocked. Lasers are off. Chopper is in. Frontend and		0	cp
		receiver irises are fully open.	-7659
L20070216_000	18:36:30	Same as before, just with a 10 dB att. in optical path	-1711	0	cp
L20070216_000	18:46:20	Same as before, now the chopper has been adjusted to	-29	0	cp
		open at 0 alt.

L20070216_000	19:16:54	PMT unblocked. Lasers off. Chopper OUT. Frontend and RX	6	0	cp
		iris fully open. Chopper replaced by adjustable iris, which is open
L20070216_000	19:28:03	This adjustable iris did not show anything out of the ordinary.		0	cp
L20070216_000	19:29:34	Now putting in chopper again and will try to place iris just in		0	cp
		front of chopper blade.
L20070216_000	19:39:54	PMT unblocked. Lasers off. Chopper IN. Frontend and RX	-2686	0	cp
		irises fully open. Now adjusting chopper in alt. NB. Sunset now
L20070216_000	19:59:59	As before, only now trying to fit an iris in front of	-139	0	cp
		chooper blade.
L20070216_000	20:08:10	Requires more work. Stopping data acq. waiting for sun to set.		0	cp
		Will continue with lasers up later.
L20070216_000	22:25:04	Rayleigh laser is up. Acquisition on 532nm channel now.	364	0	cp
		Frontend and RX iris optimized to reduce low alt. contamin.
		This is the optimized profile for rayleigh channel with the
		nearfield issue still not solved. Counts still low.

Logsheet:1

Page : 1808

Sondrestrom Lidar Operation Log

Log Sheet 2 of 2
Operators : Christian Have Pedersen
Date(s) : 070216 - 070217
File(s) : L20070216_001 - L20070217_002

Files	Time [UT]	Comments	Cnt	S	Ope
L20070216_001	22:30:10	Incremented filenumber since there will be no adjustments		0	cp
		to the optical path from now on.
L20070216_001	22:46:04	Count ref.	364	0	cp
L20070216_001	23:14:28	Adjusting half wave plate	368	0	cp
L20070216_001	23:23:06	RX half wave plate now aligned TX HW plate.	410	0	cp
L20070216_001	23:23:55	Bring up IR channel	410	0	cp
L20070216_001	23:35:13	No useful return, so now alignment will be verified.		0	cp
		Rayleigh return will be gone. Fileno. Inc.
L20070217_000	00:10:18	IR channel is aligned. Rayleigh up again.	411	0	cp
		Restarting IR app. Com error
L20070217_000	00:13:30	No profile is showing in IR plot. Will try and adjust IR chopper		0	cp
L20070217_000	00:29:31	IR profile has a spike at 0 alt. No chopper adjust can change	361	0	cp
		that. It seems the IR channel is saturated by near field return
L20070217_000	00:48:32	Bringing up Na. Taking down IR channel.	415	0	cp
L20070217_002	01:12:01	532 and 589 up and running.	527	0	cp
L20070217_002	02:10:49	End of experiment	472	0	cp