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 10Be 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 accelerationMass 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

Stable isotope separator for same rigidity

Comparison between stable and rare isotopes for Unknown sample and Standard

Isobar separator

Simultaneous measurement of 9Be and 10Be

Multi-cathode SNICS

Simultaneous loading of many samples. Presently 40 cathodes.Upgrade to 120 cathodes.

Wien Filter

AMS Beam LINE Chemistry Lab

10Be Inter-lab measurementsStandard sample: SRM4325, Procured from NIST, USANominal 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

26Al 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. 26Al signal is seen in detector and facility is now open for users.

OUR PRESENT: 10Be (T1/2 = 1.34Ma), 26Al (T1/2= .71Ma), Chronological data up to tens of Ma.

OUR FUTURE: 14C (T1/2= 5730Y), Chronological data upto 50Ka

Smaller machines are better for 14C – Higher accuracy, easy to operate

AMS at IUAC

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 14C Facilities: USA 20 Europe 38 Others countries 10 Australia 06 Japan 14

China 05 India (IOP) 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:14C is used as a tracer in biomedical research and in drug testing.

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.

Presenter TitleS. 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 14C 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 OceanographyC.M. Nautiyal, BSIP, Lucknow Radiocarbon Dating and its Application to

Palaeoclimatic and Archaeological StudiesS.S. Das, Allahabad University Application of AMS Dating for the Study of Late

Quaternary Climatic Changes in the Arabian Sea

List of Talks in Workshop on 15 September, 2011

Presenter TitleVanessa 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 SpectrometryC.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

Proposed AMS Facility for C ( Be and Al)

500kV Tandem Ion Accelerator

14C 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.

Thank You for your attention!