Description

Page : 321

Sondrestrom Lidar Operation Log

Operator(s) : E.Gudmundsson
Purpose : Routine data collection
Date(s) : 990810 - 990811
File(s) : L9908104 - L9908116
Comments : During files l9908104 to l9908111 a normal sodium run was done. During this
time Rayleigh sloping background fenomena was studied. It looked as if the
chopper was not fully open for background until about 60km! At 23:19 the the
Rayleigh beam was diverged and background data was taken revealing this slow
background increase. The files after ll9908111 contain tests.
After climing on top of the telescope around local midnight and looking at the iris
mount it was seen from the beam image projected on the mount, that the setup
was
way out of focus. The mount was moved about 1.5cm out or until the beam image
ended in a sharp spot. Using the image the iris was put in place. Closing the iris
to
1/4 of largest opening did not seem to have an impact on the Rayleigh signal
although the sodium signal suffered greatly. The opertunity was used and the
sodium part of the receiver was tweeked without any noticable improvement.
The
items tweeked were the focus and x y adjustments on the last folding mirror but as
no improvement was seen this was aborted. On the Reyleigh side an
improvement
of ca. 4.4 in signal/noise was accived without loosing to much signal. Fine tuning
the location of the iris was not atampted -> further S/N gain should be possible.
Logfile : L9908101.log

Setup:0

Page : 322
[Variables]
Dye Power=85mJ
Rayleigh Power=560mJ

[0]
90% PMT Iris=not_installed
Rayleigh System=On
Dye System=On
Daystar=In
Polerizer=In
HalfWave Plates=Tracking
Filter Wheel=2:532(.5nm)

[1]
90% PMT Iris=not_installed
Rayleigh System=On
Dye System=On
Daystar=Out
Polerizer=In
HalfWave Plates=Tracking
Filter Wheel=2:532(.5nm)

Logsheet:0

Page : 323

Sondrestrom Lidar Operation Log

Log Sheet 1 of 3
Operators : E.Gudmundsson
Date(s) : 990810 - 990811
File(s) : L9908104 - L9908112

Files	Time [UT]	Comments	Cnt	S	Ope
L9908104	22:45:29	Start of experiment	1056	0	EG
L9908104	23:14:32	I took a look at our background fenomena. It looks like		0
		there is a minimum at the altitude where the signal to noise
		approaches 1. going a bit higher the the noise floor increases
		and the noise variance as well. I'm gonna increment and
		diverge the convergence to see if it's still there
L9908105	23:19:54	Done diverging first rec has some rayleigh signal		0
L9908105	23:22:39	Changing PMT gate from 170us to 0s		0
L9908105	23:39:40	Done testing , this may be a chopper problem!!! Even when		0
		the chopper fully open for the signal it may still be opening
		for the noise.
L9908106	23:53:19	Rayleigh HG adjusted	725	0
L9908106	00:11:55	Changing setup		0
L9908110	00:13:54	Running with setup 1	793	1
L9908110	00:50:19	Sodium Convergence mirror adjusted	3822	1
L9908110	01:32:58	Counts	3858	1
L9908110	01:36:45	Rayleigh Convergence mirror adjusted	3810	1
L9908110	01:39:51	Rayleigh HG adjusted	3925	1
L9908110	02:23:18	Rayleigh Convergence mirror adjusted	3531	1
L9908110	02:35:26	Sodium Convergence mirror adjusted	4001	1
L9908110	02:41:41	Dye system tunedfrom 589.157 to 589. 158nm	3823	1
L9908111	03:20:13	Pausing to do some tests		1
L9908112	03:28:57	Iris at primary mirror focal pint installed	3915	1
L9908112	03:30:25	Closing iris half down	3821	1

Logsheet:1

Page : 324

Sondrestrom Lidar Operation Log

Log Sheet 2 of 3
Operators : E.Gudmundsson
Date(s) : 990811 - 990811
File(s) : L9908112 - L9908115

Files	Time [UT]	Comments	Cnt	S	Ope
L9908112	03:31:47	No signal loss....yet	3787	1
L9908112	03:32:56	Sodium channel suffered, reconverged, seeing how it goes	3781	1
L9908112	03:37:33	Closing iris down to 1/4	3816	1
L9908112	03:40:05	Sodium channel suffered a lot		1
L9908112	04:07:41	No luck getting better sodium counts with the iris	3770	1
L9908112	04:11:26	Trying again, closing iris	3825	1
L9908112	04:55:09	Still the same problems	3791	1
L9908112	04:56:03	Opended the iris	3936	1
L9908112	05:08:49	Moved the sodium focus	3811	1
L9908112	05:58:15	Closed iris fully SN prior to this 3812/43=88 SZA=93.2	3881	1
L9908113	06:01:28	now SN~843/5 =168 2x improvement (note @30km)	805	1
L9908113	06:02:13	Reconverging Rayleigh	805	1
L9908113	06:03:26	Done reconverging	772	1
L9908114	06:04:08	incremented output file	772	1
L9908114	06:04:39	SN after reconverging 2761/7= 394 4.4x better than before	2697	1
L9908114	06:07:01	The sodium got completly lost after closing the iris	2604	1
L9908114	06:20:07	UPS! got light into the sodium PMT	2684	1
L9908114	06:36:29	SN 2623/33=79		1	EG
L9908114	07:13:09	The SZA=88.1 and the SN~2812/115=24 @30km	2857	1	EG
L9908114	07:15:33	Pausing to change setup, incremented		1	EG
L9908115	07:18:32	SZA=87.7 SN 365/7=52 @30km		1	EG
L9908115	07:35:26	Tweeked Rayleigh Convergence	371	1	EG
L9908115	08:16:58	SZA 82	388	1	EG
L9908115	08:52:08	SZA 79.5. Shutting down sodium system	354	1	EG

Logsheet:2

Page : 325

Sondrestrom Lidar Operation Log

Log Sheet 3 of 3
Operators : E.Gudmundsson
Date(s) : 990811 - 990811
File(s) : L9908115 - L9908116

Files	Time [UT]	Comments	Cnt	S	Ope
L9908115	09:25:23	SZA 76.3 and still going (no sodium though!)	411	1	EG
L9908115	09:25:56	The solar eclipse is just about started	411	1	EG
L9908116	10:43:27	SZA 68.7 counts 427 noise 58	427	1	EG
L9908116	10:45:19	End of experiment	427	1	EG