A new beam line and injector deck for AMS measurements have been built at the 8 MV tandem accelerator of the National Institute of Nuclear Physics and Engineering, Bucharest, Romania. The main components on the low-energy side are a high-current cesium sputter source, a 90° injection magnet and a pre-acceleration stage. At the high-energy side the beam line is achromatic, consisting of two 90° analysing magnets with mass energy product 120 MeV amu and a gas-filled ionization chamber. The system will be complete with a Wien filter and a multi-anode gas detector with time-of-flight discrimination. Presently, the AMS facility is undergoing tests and routine measurements are expected to start soon.

AMS at the National Institute of Nuclear Physics and Engineering in Bucharest

The Tandem Van de Graaff accelerator is one of the main experimental facilities of the “Horia Hulubei” National Institute of Physics and Nuclear Engineering (IFIN-HH) in Bucharest-Magurele (http://www.nipne. ro). The institute, with more than 300 scientists, is the most significant player in the Romanian physics research landscape.

Laboratory Portraits: Bucharest Tandem Van de Graaff Accelerator

The HVEC-FN type tandem accelerator of the Institute of Atomic Physics in Bucharest was twice, in 1977 and 1986, severely damaged by strong earthquakes

Earthquake protection and other improvements to the Bucharest FN tandem accelerator

A 14.5 GHz ECR ion source is in an advanced stage of construction at the Institute of Atomic Physics of Bucharest, Romania. This ECR multicharge heavy ion source (RECRIS) is designed to be independently used in atomic physics research as well as an injector into the existing rf heavy ion postaccelerator of the Bucharest FN tandem accelerator. The general design and main characteristics of RECRIS are presented as well as the present status and the schedule of this project. A research program and facility was started in order to study physical ways to improve the ECR ion source performances.

Romanian ECR ion source project RECRIS

Subsequent to the installation of the seismic protection system in the HVEC FN-tandem accelerator in Bucharest, observations have been made of the efficiency of the protection devices. Performance and improvements of the new voltage divider are discussed. The SF 6 content of the insulating gas is shown to be conveniently measured using the elastic recoil technique and a robust ioniser heater is described for the HICONEX source.

Fn-tandem accelerator in bucharest after the seismic protection system installation

A concept for an earthquake protection of a tandem accelerator has been developed starting from a better understanding of the earthquake effects upon an FN column structure as a result of dynamic interaction between the ground, building and accelerator. The characteristics of earthquakes in Bucharest as well as the preliminary full-scale vibration tests are described. The main requirements for an efficient earthquake protection system are derived. These requirements are best met by a protection system that performs the vibration isolation of the accelerator tank by supporting it on spring and damper units. By means of specially designed devices (“mechanical fuses”), these units are blocked under normal operation conditions to ensure the alignment of the accelerator and are released in case of an earthquake whose acceleration exceeds a certain limit. Such a vibration isolation system might be useful for other scientific or industrial equipment too.

V. Zoran

Papers

A concept for earthquake protection of the Bucharest tandem accelerator

Earthquake protection and other improvements to the Bucharest FN tandem accelerator