Standard multiporpose line
Responsible scientist: Miguel Crespillo Almenara
This is a multi-purpose beam line placed at the 30º port of the switching magnet. The experimental station is devoted to RBS, ERDA, PIXE, NRA and, more occasionally, IL.
The experiments can be carried out in random or channelling geometries thanks to a 3-axis goniometer with an accuracy of 0.01º. The beam current is measured by means of a Faraday cup placed before the experimental chamber and the beam size is controlled with two sets of collimating slits. The analysis chamber is pumped to high vacuum and the sample holder is monitored with a small video camera.
Two silicon barrier particle detectors (12 keV resolution) are used for ion collection: a fixed detector located at 170º scattering angle and a movable detector with a set of foils and slits located in front of it (for ERDA and NRA). A silicon drift X-ray detector (Ketec Axas-A model, with 140 eV resolution) is located at 135º scattering angle for PIXE experiments. In addition, a reverse-electrode Ge detector (Canberra GR3520 model) is used for gamma-ray detection in PIGE experiments. A non-permanent set-up of optical and infrared cameras and view-ports can be attached to the vacuum chamber in order to perform IL measurements.
Ion dose is measured by a current integrator with an usual maximum precision of 0.1 nC. Recently, a new four-channel acquisition system based on an ultra-fast multiparameter multichannel analyser has been developed and implemented to improve the data collection. Due to the versatility of this station and the possibility of combining different techniques, the Standard beam line is the most suitable to perform total-IBA experiments under high vacuum conditions.