Homestake Meeting, 12/11/14
Attending: Vuk, Gary, Tanner, Gwynne, Victor, Pat, Daniel, Nelson
Homestake wiki: https://zzz.physics.umn.edu/groups/homestake/home
1) Homestake status: Gary, Tanner, and Pat visited Homestake in Nov, installed 3 stations at 4850 (all but the 17-ledge one) and two stations on the surface (near Ross and near Yates). GPS antenna on the roof of Yates admin building, Q330 master and a GPS transceiver in IT room in the admin building, GPS receivers in all underground stations. All underground stations are AC powered, two via a small battery and one via a DC power supply. Radio antenna installed on the roof of Yates admin building.
- GPS system 2014_12_11_homestake_timing.pdf (Tanner): showing timing error for each of the three stations, how far each digitizer clock is from the GPS clock. Continuous GPS signal underground, but it appears there is a non-trivial drift over time, up to several ms. It appears the stations are receiving the GPS time, they are listed at >85% for each station, so it is not clear what this drift means and whether this is a problem. Probably need Tim to understand this, should hear from him soon. Also not clear why the clock quality is not at 100%. Manual indicates that the behavior at 48D and 48C could be due to a poor signal, will have to check with Tim and Jamey.
- radios (Gary): tested radios inside a building and they worked well, so they should be programmed correctly. However, at the moment the master radio is not communicating with the surface stations. Did spectral analysis and suspect the problem is that there are many wireless ports in the admin building that are in the same band as the radio antenna. Need to find out how to re-program the radios to operate in the upper part of the band (there are several free channels there). Currently the master radio is connected to one of the ethernet ports of the antelope server, but the port is probably configured wrong. Would be good if we could fix this remotely, Gary will look into this - need information (root password) from IRIS to do this.
Currently, the second network port of the antelope server is connected to the Homestake network, to which underground stations are also connected.
- antelope software: Gary remotely logged into the antelope server and configured it, so that we now have a real-time data stream. Need VPN to log into the antelope machine, can run antelope software such as dlmon to monitor the data etc. Have to figure out how to send/download data from this computer to other remote machines. Gary will try to set things up in his office, and will send the configuration files to others, so that we can keep several copies of the data in different locations. Gary is in contact with antelope developers to figure this out, we can then decide whether we all pull data directly from Homestake or have one “master” location from which all other institutions pull the data.
- first data: Gary noticed that a station drops connection and some data, so there are gaps in the data. Another question for Tim.
Vuk will send an email to Tim et al to suggest a time to meet next week.
2) Planning next visit: Jan 12 - ?
Gary could probably go to Homestake on Jan 19 or 26. Victor is potentially free the week of Jan 12 but not later. Terry could help too, especially with battery-powered stations.
Vuk/Tanner could go Jan 12, Tanner could stay for 2 weeks. Daniel flexible.
Vuk will send an email with the proposed schedule for 2 week long trip, then can proceed with tickets etc.
3) Analysis of existing data
Gary: writing a code for 3D visualization of particle motion.
Vuk: met with Eric and Noah, have a candidate for a bug in the radiometer-rayleigh code. Noah will be looking at it more next week.