Preliminary assembly test of the TAO operation building has been completed

Operation building of the TAO telescope

At the summit of Co. Chajnantor (altitude 5640 m), the enclosure protecting the TAO telescope from harsh natural environments and the operation building with a facility to perform observation and maintenance will be constructed (Fig. 1). The enclosure is a cylindrical building which is 25 m in diameter and 24 m high, and the TAO telescope will be installed on an independent foundation placed in the center. The top of the enclosure can be rotated horizontally, and the celestial objects are observed through opening and closing doors (slits).

The operation building is a three-story building, 27 m long, 17 m wide, and 15 m high, located on the south side of the enclosure. The first floor will house a generator room, electrical room, laboratory, warehouse, and garage. The observation room, computer room, and lounge will be located on the second floor, and the room with the highest ceiling will house the mirror deposition equipment, mirror cleaning equipment, and a large crane for maintenance. On the third floor, there will be a laboratory and warehouse. A bridge connects the second floor of the operation building to the observation floor (non-rotating section) of the enclosure. When the primary mirror of the TAO telescope is re-evaporated, it is placed on a large cart and transported across the bridge to the mirror deposition and mirror cleaning equipment in the operation building.
In the early phase of TAO operation, securing power supply with generators on the first floor of the operation building, we will control the telescope from the observation room on the second floor and carry out scientific observations. In addition, the operation building will be connected via a wireless network to the TAO base facility in San Pedro de Atacama, 50 km away, making remote observations possible. In the near future, the power supply and network in the operation building will be connected to the outside via stable and high-speed fiber lines and power lines that will be set along the access road to the summit of Co. Chajnantor.

▲Fig. 1: Conceptual drawing of completion of the TAO summit facility

Preliminary assembly test in Japan

Structural components of the operation building, including steel frames and walls, were manufactured in Japan. In order to carry out construction work reliably and smoothly in a harsh environment at an altitude of 5,640m, we decided to make a preliminary assembly of steel components for the operation building in Japan.

Preliminary assembly tests of steel components of the operation building were conducted in Kazo City, northern Saitama prefecture, starting in May 2020. Most of the steel frame members were assembled, and the accuracy and strength of the joints and the dimensions were checked. We also checked the accuracy of the joints with non-steel frame components. (Fig.2, Fig.3)

▲Fig.2. Preliminary assembled steel components of the operation building (in Kazo, Saitama)

▲Fig. 3. Preliminary assembled second floor of the operation building

Preliminary assembled components of the operation building were demolished in July 2020. The Steel and other components were carefully packed to withstand long-term transportation to Chile and storage, divided into eight ships, departed from Yokohama Port, and arrived at Angamos Port in Chile safely. They will be stored at the foot of Co. Chajnantor until construction work starts at the summit.