Date:
Wednesday, July 18, 2018
Telescope:
CTIO Blanco 4-m
Submitter:
Will Dawson
Submitter Email:
Observer Support:
Hernan Tirado
Night Assistant:
Jackie Seron
Also Present:
Claudio Aguilera
Problems:
At UT 3:50 we experienced an Interlock Alert causing the observations to halt. Once it was green, we tried to observe agains and received the same error. The TO restarted the lower level of the TCS, and resolved the issue at UT 04:14 (total loss of time 24 minutes).
Program:
Proposal:
2018A-0273
Target of Oportunity:
No
Time Observed:
8.25
Time Engineering:
0.0
Time lost technical:
0.5
Time lost weather:
3.0
Time lost other:
0.0
Description:
PALS black hole microlensing survey
Primary Investigator:
Will Dawson
Email:
Institution:
Lawrence Livermore National Lab
Instrument:
CTIO 4m DECam
Organization:
NOAO
Total Program Time:
11.75
| Total Times | Time Observed | Time Engineering | Time lost technical | Time lost weather | Time lost other | Total Program Time |
|---|---|---|---|---|---|---|
| 2018-07-18 | 8.25 | 0.0 | 0.5 | 3.0 | 0.0 | 11.75 |
Printer-friendly version
The first part of the night was lost due to humidity near the limit, and started observing at UT 02:00 when the humidity fell to ~60%. Seeint was poor during the first part of the night (~3-4"). We suspect that it was due to an ~4 degree celcius tempterature differential between the outside temp and dome temp (colder outside). At UT 3:15 we decide to open the dome louvers to try and cool it down, despite concerns that it might cause the humidity to increase slightly (this was deemed a reasonably safe risk since the humidity had been stable at ~55% for about the past 3 hours). The temperature of the mirror (pmas_temp) quickly fell 3 degrees C, however for some reason after about 30 minutes it quickly rose 2.5C and then fell agian by ~2C about 10 minutes later.
Seeing worsened as the night proceeded, with both the DIMM and DECam measured seeing being greater than 4" for the vast majority of the night. The worst seeing topped out above 13". In the later quarter of the night the 30 minute average seeing was 6". Gemini South also experienced worse than normal seeing (DIMM > 2") for the entire night, although it was closer to 2". Note that the Quarter Night Summary below will only allow you to enter a seeing value up to 3", which is why these are not representative of the report.