ASTRID was built as a dual-purpose storage ring able to store either ions interacting with electrons or laser beams for atomic and physics research, or electrons for synchrotron radiation. Initially ASTRID was used 100% for stored-ion physics, and during the period ~1995-2005 ASTRID was operated 50% with ions and 50% for synchrotron radiation. After the invention of ELISA, the ion-storage programme was gradually moved away from ASTRID to ELISA, which could deliver much more running time with ions. ELISA is a newer electrostatic storage ring which is able to store particles with a much wider range of masses than ASTRID, however only at energies up to 25 keV per charge state. 

For 10 years, the ion storage programme (at both ASTRID and ELISA) was concerned with supporting the activities of ACAP, the Aarhus Centre for Advanced Physics, and AMO, the Atomic Molecular and Optical Physics Group at the Department of Physics and Astronomy, Aarhus University.  The present ion-storage programme at ELISA is run by Professors Jens Ulrik Andersen, Lars Henrik Andersen, Steen Brøndsted Nielsen and Preben Hvelplund.

The type of experiments performed on stored ions include;

• electron-ion interactions using an electron cooler
• spectroscopy and lifetime studies, particularly of negative ions
• cluster physics

The table below lists all the ions which have been successfully stored in ASTRID. 
 

Positive ions
D+	4He+	6,7Li+	6Li++	14N+	16O+	19F+
20Ne+	24Mg+	40Ar+	151Eu+	166Er+	40Ar++	132Xe+
Xe++	129Xe8+	129Xe15+	129Xe20+	12C3+
H2+	H3+	HD+	D2+	3He4He+	4He2+	H2O+
HDO+	H3O+	D3O+	CH3+	C2H2+	13C16O+	13C16O2++
14N15N+	14N15N++	14N16O+	16O2+	20Ne2+	12C16O2+	12C16O2++
12C3+	12C4+	12C4H5+	12C32S2+	C48-60+	C70+	12C16O++
13C16O++	13C16O++	16O18O++	C60+
Negative ions
H-	D-	3He-	7Li-	9Be-	12C-	16O-
19F-	28Si-	32S-	35Cl-	40Ca-	56Fe-	88Sr-
138Ba-	174Yb-
4He2-	12C2-8-	16OH-	12C14N-	11B16O-	16O2-	16O3-
19F2-	12C16O2-	14N16O2-	14N16O3-	14N16O2{H2O}-	32S16O2-	34S2-
34S18O2-	12C32S2-	Al1-12-	C48-60-	C70-

More information about these activities can be found on the AMO pages. 

 

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Last Modified 08 July 2009