Courtesy Photo

LAMAR—In early August, Pierre Auger Cosmic Ray Observatory consortium colleagues visited from Colorado State University to refit the LCC tank with insulation. After one year of temperature data from an uninsulated tank, the Auger Project is ready to take data from an insulated tank. “The proposed site in southeastern Colorado has colder winters than Argentina (where the southern hemisphere site is located) which will affect water freezing in the tanks,” says Dr. Pablo Bauleo. “We want to understand how the water in the insulated tank will be affected over the course of the next year, so we make no design errors in the amount of insulation for the northern hemisphere detector tank design.” If too much water freezes in the tank, it could damage the sensitive electronics inside and affect the reliability of the measurements they take.

The refit consisted of pumping water out of the liner inside of the tank - all 3,000 gallons, removing the liner, fitting the inside surfaces (except the bottom) with blue flexible polystyrene held in place with nylon rivets, then replacing the liner and pumping back in the water. This will not be the way the proposed Auger North tanks will be insulated - they will have a commercial insulation built in during production, but it is an easy and cost effective way to obtain insulated tank data from the area. Although the water inside of the actual detectors in Argentina is extremely pure, the LCC tank has only reverse osmosis (RO) treated water. Since LCC’s tank has not been fitted with cosmic ray detection devices, but only temperature probes, the need for ultra-pure water is unnecessary at this stage. The Auger colleagues decided to keep the water that was inside LCC’s tank because it was already at an equilibrium temperature with the local environment. “If we were to put in new water from the RO plant in Las Animas, we would have to wait at least a month or two for it to reach equilibrium with the local environment,” said Dr. Jeff Brack. “This would be one of the variables in our data that would make it difficult to create a model of the temperature inside of the tank. We decided to eliminate this possible problem by renting a tanker truck in Lamar and re-using the water, which is already at the correct local temperature.”

CSU graduate students, Yevgeniy Petrov and Michael Vertuli, worked inside of the tank for one whole day to fit and secure the insulation. “It was hot and hard work inside,” said Yevgeniy, “but the cooler weather allowed us to work during the day, which we couldn’t have done during the latter parts of July.”

For more information about the Auger Project, or specifically about the proposed northern site, visit www.augernorth.org or call Brad Thompson at LCC 719.336.1548.