Burchard, M.

Dedera, S.

Glasmacher, U. A.

Trautmann, C.

GSI Repository

GSITemplate2007 Online Raman on M-branch: First results * Sebastian Dedera1#, Ulrich A. Glasmacher1, Michael Burchard1, Christina Trautmann2,3 1Institute of Earth Sciences, University of Heidelberg, 2GSI Darmstadt, 3Technische Universität Darmstadt Raman spectroscopy, as a tool to determine material change caused by accelerated ions or natural radioactive decay, is widely used in geoscience and material research. Due to many issues in the current workflow with standard equipment, in 2014, an online and in-situ Raman system to irradiate matter with swift heavy ions has been devel-oped. The Raman system is established at the 400 mm spectroscopic chamber of the M3-branch and is fed with accelerated swift heavy ions by the UNILAC. For tech-nical details see the associated report in this volume [1].  To test the system’s ability to detect changes in the properties of the irradiated material, calcite has been cho-sen for first experiments, because calcite reacts very sen-sitive to ion irradiation and the changes of calcite in Ra-man spectra are known [2,3]. The calcite crystals from Chihuahua, Mexico were irradiated at the M3 - branch of the UNILAC, GSI with Au+26 , 4.8 MeV/u, 2 Hz and an extraction time of 1.2 ms.  After calibration, alignment and focusing of the system, one calcite crystal has been irradiated with Au ions in steps from 1 x 109 ions/cm2 until a fluence of 1 x 1012 ions/cm2. Raman spectra were taken after each irradiation step with 20 s acquisition time with 3 repetitions. A first brief analysis of the Raman spectra of calcite show four major changes during irradiation (Fig. 1). The two peaks at 156 and 284 cm-1 at the beginning of the spectra are decreasing in intensity with increasing fluence, but they are still visible at 1 x 1012 ions/cm2. The next change in the spectra is the peak at 437 cm-1. It arises with in-creasing fluence and is visible for the first time at 2 x 1010 ions/cm2. Its intensity is increasing after this fluence, but it reaches its maximum at 5 x 1011 ions/cm2. The last peak to be mentioned is the biggest peak of the spectra at 1087 cm-1. It is getting wider with increasing fluence, starting at 5 x 1011 ions/cm2. In conclusion, the first results of the new online Raman system at M3 are very promising. The system works and the results are in quality and quantity comparable with the results of established methods with all the advantages of o online Raman system with its in situ measurements. After eliminating some minor problems, a powerful tool to measure various materials before, during and after the irradiation with swift heavy ion is at hand. A more de-tailed analysis of the obtained data is in progress.  [1] S. Dedera et al., “Online Raman Measurements on M-Branch”, GSI Science Report 2014 [2] S. Dedera et al., “Online Raman Measurements of Calcite and Malachite during Irradiation with Swift Heavy Ions”, in prep. [3] S. Pabst et al., Swift heavy ion induced damage in calcite, aragonite and dolomite: a Raman spectroscop-ic study”, in prep.    * Work supported by BMBF Verbundprojekt 05K10VH1 #  Sebastian.Dedera@geow.uni-heidelberg.de Figure 1: Raman spectra of calcite, taken with the new online Raman system on M3-Branch GSI SCIENTIFIC REPORT 2014 APPA-MML-MR-11DOI:10.15120/GR-2015-1-APPA-MML-MR-11 263

Online Raman on M-branch : First results

http://repository.gsi.de/record/183997/files/APPA-MML-MR-11.pdf

Online Raman on M-branch : First results

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