VSR Ammonia Data Collection
4 August 2015
Systems started at 0930, Data collection Started at 1030, Completed at 1420
Lab Temperature = 22.5C
Lab Humidity = 55%
Pressure = 1090 mb (sea level)
BB = SR-800 4 inch
General approach:
1. The blackbody was set to the indicated temperature (18, 22, 27, 32, 37, and 42C) and allowed to
stabilize and lock.
2. With the cell in place, a purge rate of 325 cc/min of dry nitrogen was applied for 20 minutes.
3. The flow was stopped, the cell blocked in and a background consisting of 20000 scans was
collected
4. The cell was then charged with pure ammonia vapor at a rate of 300 cc/min for 3 minutes
5. The cell was then purged with dry nitrogen at a rate of 325 cc/min for 1 min, 45 seconds to
reduce the cell concentration below 1 abs.
6. The cell was then purged with dry nitrogen at a rate of 325 cc/min for approximately 5 minutes
while 20000 scans were collected.
7. Noise measurements were collected at 35, 45 and 55C with and without the cell.
measurements were made using the VSR side port with ZnSe corrective optics installed.
Legend
NC – Noise No cell present Noise Measurement
NH3-Bkg - Cell present background
NH3 – Declining cell data
Temp
Setting
(Deg C)
18
18
VSR File
VSR_NH3_bkg
T18_08_04_15
VSR_NH3_T18_08_04
_15
Scans
Cell
Present
20000
Yes
20000
Yes
Background Purge
Cell Fill
cc/min
Time
(min)
cc/min
325
20
300
Cell pre-Purge
Declining Cell
Time
(min)
cc/min
Time
(min:
sec)
cc/min
Time
(min)
3
325
1:45
325
5
22
22
27
27
32
32
37
37
42
42
35
45
55
VSR_NH3_bkg
T22_08_04_15
VSR_NH3_T22_08_04
_15
VSR_NH3_bkg
T27_08_04_15
VSR_NH3_T27_08_04
_15
VSR_NH3_bkg
T32_08_04_15
VSR_NH3_T32_08_04
_15
VSR_NH3_bkg
T37_08_04_15
VSR_NH3_T37_08_04
_15
VSR_NH3_bkg
T37_08_04_15
VSR_NH3_T42_08_04
_15
VSR_Noise_NC
T35_08_04_15
VSR_Noise_NC
T45_08_04_15
VSR_Noise_NC
T55_08_04_15
20000
Yes
325
20000
Yes
20000
Yes
20000
Yes
20000
Yes
20000
Yes
20000
Yes
20000
Yes
20000
Yes
20000
Yes
12000
No
325
10
12000
No
325
10
12000
No
325
10
325
325
325
325
20
300
3
325
1:45
325
5
300
3
325
1:45
325
5
300
3
325
1:45
325
5
300
3
325
1:45
325
5
300
3
325
1:45
325
5
20
20
20
20