Description

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Sondrestrom Lidar Operation Log

Operator(s) : Katelynn, Greer, Christian, Have, Pedersen, Christian, Have, Pedersen, Christian Have Pedersen
Purpose : System optimization and routine data collection
Date(s) : 080719 - 080720
File(s) : L20080719_000 - L20080720_002
Comments : Began run by converging the system (very little was needed) and attempting to
optimize the 1/2 wave plates (this was not very sucessful given the low signal
level). Next, I turned the lasers off and recorded background noise for about an
hour. Afterwards, I began Steve's requested experiment where I would take data
for one hour in one plane, then change the plane of polarization and take data for
another hour and so on. However, after about an hour I identified a possible PMC
and decided to record it with the sun tracking flipping routine for as long as I
could. I ended data collection after the PMC apparently dissipated and well after
the sun has risen.
Logfile : l0807200.log

Setup:0

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[0]
front end Iris=not_installed
Rayleigh System=On
Rayleigh Field stop=0.5mm
Rayleigh path attenuation=0dB
Dye System=Off
Sodium Field stop=0.5mm
Etalon=In
Daystar=4A_In
Polarizer=In
HalfWave Plates=Tracking
Rayleigh Filter=2:532(.5nm)
Rayleigh seeding=off

Logsheet:0

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Sondrestrom Lidar Operation Log

Log Sheet 1 of 3
Operators : Katelynn, Greer, Christian Have Pedersen
Date(s) : 080719 - 080720
File(s) : L20080719_000 - L20080719_000

Files	Time [UT]	Comments	Cnt	S	Ope
L20080719_000	23:34:34	Start of experiment		0	cp
		SP Energy: 5250 mJ; Counts=3686
		Big Sky 1 = 0.70; Big Sky 2 = 0.70
	23:35:28	Attempting to Converge system		0	cp
	23:45:10	Rayliegh converged		0	cp
	23:45:20	Raman PMT turned on		0	cp
		Power = 0.750, 10 dB neutral density filter in place before
		chopper
	23:48:40	Raman signal bad, we are going to try checking the path		0	cp
	00:00:48	RX raman signal seems to be hitting side of iris		0	cp
		Iris was set at 7.5, opening to 10.0
		Now we have signal induced noise in 532
		This does not work
	00:03:05	Returning Iris to 7.5		0	cp
		Christian thinks that because we are not tracking the
		sun right now, this may be enough to drown the Raman
		signal
	00:06:01	Turning on Sun-tracking		0	cp
	00:09:32		31	0	cp
	00:09:37	Changing Raman attenuation to 6 dB and replacing cabinet		0	cp
	00:17:57	Raman signal still not improved; returning to 10 dB		0	cp
		Final Beam splitter before filter stack is producing a
		distorted beam shape
	00:28:06	Christian is now going to try to manipulate the beam splitter		0	cp

Logsheet:1

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Sondrestrom Lidar Operation Log

Log Sheet 2 of 3
Operators : Christian Have Pedersen
Date(s) : 080720 - 080720
File(s) : L20080719_000 - L20080719_000

Files	Time [UT]	Comments	Cnt	S	Ope
L20080719_000	00:28:41		32	0	cp
	00:39:10	Beam splitter is fine		0	cp
	00:39:31	We have discovered a turning mirror in the far upper		0	cp
		right corner that is a bit loose, likely being bumped when
		the cabinet cover was put on, that caused the beam
		to not fall through the following iris, mirror has been put
		back into the correct position
	00:42:14	Yeah, Raman profile problem solved!		0	cp
	00:45:00	Turning on sun tracking and flipping routine		0	cp
	00:47:50		-5	0	cp
	00:48:34		39	0	cp
	00:55:30	Christian and I will now attempt to optimize the		0	cp
		half wave plates
	00:56:36	Changing software to turn off flipping, with sun tracking		0	cp
	01:00:19	Capping 607 channel and opening iris		0	cp
	01:04:12	There does seem very much background to minimize with		0	cp
		the RX wave plate, it seems to be correct where it was
		Perhaps we will try earlier in the day another time
	01:15:55	TX also very difficult to optimize, decide it is best at 150		0	cp
		Turning 607 channel back on
	01:25:16	Christian noticed a low-frequency oscillation on		0	cp
		O-scope while optimizing
	01:28:36	We have decided to look just at the background noise		0	cp
		Shutting down lasers

Logsheet:2

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Sondrestrom Lidar Operation Log

Log Sheet 3 of 3
Operators : Christian Have Pedersen
Date(s) : 080720 - 080720
File(s) : L20080719_000 - L20080720_002

Files	Time [UT]	Comments	Cnt	S	Ope
L20080719_000	01:31:15	Recording Background only		0	cp
	01:36:37		-1	0	cp
	02:27:33	Warming the lasers back up		0	cp
	02:40:21	Begin Q-swtiching		0	cp
L20080720_000	02:42:40	Begin experiment for flipping plane every hour		0	cp
	02:43:56		18	0	cp
	02:47:23		40	0	cp
	03:20:34	I am a bit concerned about the shape of the 532 signal		0	cp
		I don't know what it means...	39
	03:43:32	It looks like there may be a PMC in the signal		0	cp
	03:45:51	Because of the likely PMC, I will now go to the		0	cp
		sun tracking flipping routine
	04:28:10		39	0	cp
	04:54:45	PMC seems to be thinning	41	0	cp
L20080720_001	05:38:46		40	0	cp
	06:06:58		40	0	cp
L20080720_001	06:36:20		40	0	cp
	07:04:24		38	0	cp
	07:19:11	The sun has begun to rise		0	cp
L20080720_002	07:50:55	PMC seems to have dissipated	43	0	cp