30luflS8 
 
 MDDC-994 
 
 UNITED STATES 
 
 ATOMIC ENERGY COMMISSION 
 
 OAK RIDGE 
 
 TENNESSEE 
 
 TRANSMUTATIONS WITH fflGH ENERGY 
 DEUTERONS AND HEUUM IONS IN THE 184-INCH CYCLOTRON 
 
 by 
 
 B. B. Cunningham 
 R. C. Thompson 
 P. R. O'Connor 
 G. T. Seaborg 
 H. H. Hopkins 
 D. R. Miller 
 M. Lindner 
 I. Perlman 
 
 University of California 
 
 Published for use within the Atomic Energy Commission. Inquiries for additional copies 
 and any questions regarding reproduction by recipients of this document may be referred 
 to the Technical Information Division, Atomic Energy Commission, P. O. Box E, Oak Ridge, 
 Tennessee. 
 
 Inasmuch as a declassified document may differ materially from the original classified 
 document by reason of deletions necessary to accomplish declassification, this copy does 
 not constitute authority for declassification of classified copies of a similar document which 
 may bear the same title and authors. 
 
 I \ Date of Manuscript: April 28, 1947 
 
 Document Declassified: May 15, 1947 
 This document consists of 2 pages. 
 
 onsiTQRY 
 
MDDC-994 
 
 TRANSMUTATIONS WITH HIGH ENERGY 
 DEUTERONS AND HELIUM IONS IN THE 184-INCH CYCLOTRON 
 
 By B. B. Cunningham, H. H. Hopkins, M. Lindner, D. R. Miller, P. R. O'Connor, 
 I. Perlman, G. T. Seaborg, and R. C. Thompson 
 
 The successful operation^ of the Berkeley 184-inch cyclotron to produce useful beams 
 of deuterons and helium ions of approximately 200 and 400 Mev, respectively, has made 
 possible the radiochemical identification of many of the transmutation products of nuclei 
 excited to very high energies. Products with considerably lower atomic number than the 
 target were observed in all cases. For example, with 200 Mev deuterons on ^^^s^^ activ- 
 ities were found representative of all elements from 3486 to 25Mn with lower elements 
 not excluded. Both negative beta-particle and positron (or orbital electron capture) activ- 
 ities are noted, indicating reactions both of multiple neutron ejection and multiple charged 
 particle ejection. For example with deuterons on ySb^^^ ^"** ^23 ^oth 6.7-hour 48CdlO''^ 
 and 2.5-day ^gCd}'-^ were produced and with 33AS75 cobalt activities tentatively assigned 
 to 27C055 or 27Co54 (^12 Hr.) and 27C06I ('^'1.8 Hr.) 2 were found. 
 
 For the formation of light isotopes, several different reactions are possible since in 
 most cases the products will not be shielded from formation through a chain of short-lived 
 positron (or orbital electron capture) ancestors following the ejection of different combi- 
 nations of neutrons and charged particles in the primary reaction. As an example from 
 deuterons on 29Cu^3 ^^ ^^, the formation of a new 8-hour iron positron emitter assigned 
 to 26^® ^^y ^^ represented by the expression, Cu®3(d,4zl3a)Fe°^, which indicates that 
 four units of charge and thirteen mass units are lost in arriving at the product. In the case 
 of the heavier isotopes it may be possible to write somewhat more definite reactions of 
 the type Sbl23(d,2a2n)Cd^^5 and As'^5((i,p3a3n)Co^^, although negative beta-particle emit- 
 ting parents are certainly possible. 
 
 Uranium was bombarded with 400 Mev helium ions and a wide range of activities were 
 identified both in the heavy element region and in the region of the fission products. Rep- 
 resentative of the heavy isotopes observed were 88Ra223(AcX), QQRa.^^\TiiX.) , and ssAt^^' 
 The fission product distribution is characterized by a much shallower dip between the max- 
 ima than is the case for slow neutron fission, and the yields of the lightest observed fis- 
 sion productB are much higher. 
 
 The various aspects of this work will be published more fully by the individual groups 
 of investigators. 
 
MDDC-994 
 
 REFERENCES 
 
 1. W. M. Brobeck, E. O. Lawrence, K. R. MacKenzie, E. M. McMillan, R. Serber, 
 D. C. Sewell, K. M. Simpson, andR. L. Thornton, Phys. Rev. 71, 449 (1947). 
 
 2. T. J. Parmley and B. J. Moyer, Abstract No. E6, this meeting of Am. Phys. Soc. 
 
Digitized by tine Internet Arclnive 
 
 in 2011 witli funding from 
 
 University of Florida, George A. Smathers Libraries with support from LYRASIS and the Sloan Foundation' 
 
 http://www.archive.org/details/transmutationswiOOuniv 
 
UNIVERSITY OF FLORIDA 
 
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