10/18/08
| DIAL Daily Activity Log | Telescope | |||||||||||
| Type: | Ch5 | Ch2 | Ch1 | |||||||||
| Date: | 10/18/2008 | Time Zone: | GMT-5 | Primary Diameter | 16'' | 4'' | 4'' | |||||
| Operator: | Kuang | F/# | 4.5 | 1 | 1 | |||||||
| Sky Condition | clear | Field Stop | 1.5 mrads | 4.3mrads | 4.3mrads | |||||||
| Electronics | ||||||||||||
| Laser power | before data acquisition | |||||||||||
| HV (kV) | Green(W) | UV(mW) | BBO Crystal | PMT | EMI8931QA | R7400U-03 | R7400U-03 | |||||
| 285 Laser: | 1.5 | 72 | 289.102 | Voltage | 1850V | 800V | 800V | |||||
| 291 Laser | 1.5 | 57 | 297.088 | Serial # | 49 | |||||||
| Ch5 | Ch1 | LICEL | ||||||||||
| Alignment | No | No | didn't align due to some thin clouds | |||||||||
| Disc Level | 8 | 8 | 8 | |||||||||
| ADC Range (mV) | 500 | 500 | 500 | |||||||||
| Filter | solar | solar | solar | |||||||||
| Data Description | ||||||||||||
| Delay (us)* | ND Filter | |||||||||||
| Time | resolution(min) | Ch1 | Ch2-285 | Ch2-291 | Ch5 | Ch1 | Ch2 | Ch5 | ||||
| 12:09 | 2 | 0 | 192, 1.7 | 202, 1.7 | 2, 13 | NA | NA | NA | ||||
| Purpose | taking data | |||||||||||
| Comments | change the ADC range of channel-1 from 100 to 500. The signal before bin 20 exceeds the Licel limit if seting the range as 0-100mV. | |||||||||||
| *The first value is the delay set on the pulse generator; the second one is the actual delay. | ||||||||||||
Range-corrected signal
Ozone retrieval (10-min resolution)
Ozonesonde measurement at 13:03 local time
A one-degree least-square polynomial fit (linear fit) is performed on five consecutive bins (binwidth=150m) in signal processing. No smoothing for the signal. Compared with the 5-point running smoothing, the retrieval result doesn't have a big change especially for ch2 and ch5. 5-point smoothing seems to result a smoother retrieval. We should be very careful about using numerical filter and gluing analog-PC data for ch1 since the signal decays very quick at near-range. Any error in data processing can lead to huge errors in retrievals. The gluing altitudes for 285 and 291 bascially should be the same for our case (285 outgoing power is a little bigger than 291). The ratio of analog/PC (after deadtime and background correction) should be constant around the gluing altitude. We are conversative about the ch1 retreivals.
There is a cloud interference at 17:10. Decreasing ozone between 3 and 5km after 18:00. Stable ozone layer at ~6km.
