IUAC Pelletron Accelerator The first accelerator 15UD Pelletron was installed in 1990 and has been operational for more than 20 years. This accelerator is consistently operating with an uptime of more than 95%. The 15UD accelerator was modifed/upgraded to start AMS prgram to study 10 Be and 26Al.
> 400 User groups from : 80 Universities 53 Colleges 58 Institutes
Areas of Research at IUAC Nuclear Physics Materials Science Atomic & Molecular Physics Radiation Biology Accelerator Mass Spectrometry
ACCELERATOR MASS SPECTROSCOPY PROGRAM AT IUAC Method : Conversion of sample to Ion beam and Subsequent acceleration Mass analysis in magnets (ME/Q2) & Velocity selectors (E/M) Nuclear Charge determination(z) in DE- E detectors Advantages ; Ultra sensitive tool for detection of trace elements ( 1 Part in 1015) Used for detection of long lived radio-isotopes : 10Be, 26Al, 36Cl, 41Ca, 59Ni, 129I Wide spread use in Archeology, Geology, Biomedicine, Environmental and Materials Science Special advantage in tandem Accelerator : Use of negative ions prevent contamination of 14N in 14C studies. Stripper eliminates molecules
Comparison between stable and rare isotopes for Unknown sample and Standard Isobar separator Simultaneous measurement of 9Be and 10Be Stable isotope separator for same rigidity
Multi-cathode SNICS Simultaneous loading of many samples. Presently 40 cathodes. Upgrade to 120 cathodes.
Wien Filter AMS Beam LINE Chemistry Lab
Be Inter-lab measurements 10 Standard sample: SRM4325, Procured from NIST, USA Nominal value: 2.68x10-11( Decay counting) Present accuracy is ~ 7% depending on the accelerator stability.
Recent 10Be measurements Growth rate measurements of Mn-nodules from Indian Ocean Sedimentation rate and paleoclimate modeling using 10Be in lagoonal sediments from Kaluveli, near Pondicherry Study of 10Be concentration from Southern Indian ocean sediments Determination of sedimentation rate on sediment core from Uttarangudi river sediments Sediment samples from Antarctica lake were measured. Sample processed at Pondicherry University chem lab
Workshops (2005, 2007, 2010, 2011 ) about AMS at IUAC. A special workshop ISMAS-DM HEAL was conducted by ISMAS in collaboration with IUAC in April, 2011. IUAC has conducted many acquaintances programs in different universities to generate awareness about AMS. There are 12 projects currently being run under AMS program 26 Al AMS Facility development. Standard solution is procured from Univ. of California and converted here in Al2O3 powder form. Tested in Ion sources and found better current, if mixed with Nb powder. 26 Al signal is seen in detector and facility is now open for users.
AMS at IUAC OUR PRESENT: 26 10Be (T 1/2 = 1.34Ma), Al (T1/2=.71Ma), Chronological data up to tens of Ma. OUR FUTURE: 14C (T 1/2= 5730Y), Chronological data upto 50Ka Smaller machines are better for 14C Higher accuracy, easy to operate
STATUS OF AMS FACILITIES ALL OVER THE WORLD (May, 2011 Prepared by Walter Kutschera) There are around 107 AMS facilities all over the world ~94 facilities are for 14C Major C Facilities: USA Europe Others countries Australia Japan China India (IOP) 14 20 38 10 06 14 05 01 Single sample measurement charge is ~ US $600 depending upon the laboratory.
Importance of 14C in the various fields of Science: Geosciences: Dating of Terrestrial sediments and peat profiles to investigate climate change in recent past. Oceanography: Radiocarbon dating of ocean water to validate Ocean circulation model. - An important factor for global climate and marine biology. Glaciology (Ice Cores): Study of climatic conditions in the past with the 14C measurement from the CO2 trapped in the ice cores as air bubble. Archaeology: Providing the chronology for the archeological events - 14C is the most suitable isotope.
Climate Change and Atmospheric Sciences: CH4 is a main greenhouse gas, whose concentration in the atmosphere has increased dramatically. AMS measurements of 14C offer the considerable advantage of requiring relatively small air samples, typically 1 m3. Measurements of 14CH4 from a clean southern-air sampling site in New Zealand showed that about 25% of atmospheric methane may be fossil in origin. Biomedicine Sciences: C is used as a tracer in biomedical research and in drug testing. 14 AMS offers the major advantage of very much small doses Reduces the expense of preparing suitable amounts of labeled compounds, greatly reducing the problems of disposal and allowing studies in humans.
List of Talks in Workshop on 15 September, 2011 Presenter Title S. Balakrishnan, Pondicherry University Application of Cosmogenic Nuclides in Geological Sciences B. Nagender Nath, NIO, Goa Some Applications of Cosmogenic Nuclides in Marine Geological, Geochemical and Oceanographic Studies Rajeev Saraswat, NIO, Goa Understanding Past Monsoon Changes: Role of AMS 14 C Dating J. K. Pattanaik, IISER Kolkata Determining the Millennial Scale Weathering Rates in the Drainage Basin using 10Be and 26Al M.G. Yadava, PRL, Ahmedabad Compound Specific Radiocarbon Analysis of Sediments using AMS Method Ravi Bhushan, PRL,Ahmedabad Application of Radiocarbon in Oceanography C.M. Nautiyal, BSIP, Lucknow Radiocarbon Dating and its Application to Palaeoclimatic and Archaeological Studies S.S. Das, Allahabad University Application of AMS Dating for the Study of Late Quaternary Climatic Changes in the Arabian Se a
Presenter Title Vanessa Andrade, IISc, Bangalore Palaeo-tsunami Age Estimates from the Andaman and Nicobar Islands using Radiocarbon Samples, their Depositional Environment and the Associated Coseismic Geomorphology A. H. Laskar, PRL, Ahmedabad Exploring Organic Carbon Cycling in Indian Soils using AMS Radiocarbon Dating Pankaj Kumar, IUAC, New Delhi Role of Chemistry in Accelerator Mass Spectrometry C.S. Dubey, University of Delhi, Delhi Cosmogenic Nuclides for the Studies of Erosion, Weathering and Tectonics Process in Orogenic Belts (Teesta And Satluj River Area) S.P. Dhal, Pondicherry University Puducherry Preliminary 10Be Studies on Sediment Core Samples from Cauvery Delta Ramya Bala P, IISc Bangalore Paleo-environmental Reconstruction from the Montane Peat Bogs of Nilgiris: A Multi Proxy Approach
Proposed AMS Facility for C ( Be and Al) 500kV Tandem Ion Accelerator
14 C sample Preparation Laboratory: The methodology of AMS starts with the collection of samples from various sites depending upon the field of study. The sample preparation procedure involves the following steps. a) Pretreatment: Extracts the carbon from the sample material and removes the contaminants. The pretreatment procedure varies on the basis of sample origin and type. b) Combustion: CO2 is produced from pretreated residue of the sample. The purified CO2 is collected in glass tubes for converting into graphite. c) Graphitization: This step converts the CO2 into graphite. Automated graphitization unit : Many labs have developed automated graphitization units to minimize the human efforts and to increase the throughput of the sample processing. AMS lab. at PSI, ETH Zurich has developed a fully automated and compact system.
Proposed place of installation of the AMS system 1.7 MV Pelletron for RBS AMS
Time Schedule for 14C Facility Sanction of Project: Expected Dec 2011 Procurement of Accelerator System: 1 Yr 2 mo (Feb 2013) Testing of Accelerator system & Setting up of sample preparation Lab: + 6 months (Aug 2013) Regular operation for users: + 4 mo (Dec 2013)
The two Pelletron Accelerators at IUAC are central facilities for accelerator based research programs. 14C AMS facility will be a National facility and all the universities as well as research institutions are expected to utilize this facility.
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