A Transport Equation Theory of Electron Scattering

The use of the Boltzmann transport equation to describe electron scattering in electron microscopy and electron probe microanalysis is discussed. A method of solution is given in which the transport equation is divided into angle and energy intervals. This gives rise to a number of coupled first order differential equations. Separation into forward and backward travelling components of the electron flux distribution enables the correct boundary conditions to be imposed. Solutions are derived which take the form of matrix operators analytic in both depth and target thickness. These matrices allow derivation of other physical quantities such as X-ray or Auger electron production. Calculations using this method are fast and accurate. Results are presented showing angular distributions of backscattered electrons and the variation of the backscattered fraction with angle of incidence and atomic number. The variations of backscattered, transmitted and absorbed fractions with target thickness are presented. The theory has also been applied to the calculation of the energy distributions of backscattered electrons, energy dissipation and X-ray production as functions of depth and the Auger backscattering factor. It appears that electron scattering in thick targets is not amenable to treatment using simple models. This is because most of the features of interest are determined by a combination of medium angle scattering (\u3c 20°) and large angle scattering (20-90°). Nevertheless certain approximations within the present framework, which describe multiple scattering correctly, can give some useful insights

CSSP Newsletter-No.43 (1974)

February 1974, No. 43 Rome: Evangelization and Basic Communities --(p.1-2) Provinces: Ireland, Spain --(p.2-4) Mission News: Senegal, Cameroons, Gabon, Tanzania, Puerto Rico, Nigeria, East Africa (AMECEA), Ethiopia --(p.4-12), Pastoral experiment in Zaire --(p.9) Our Dead --(p.12

CSSP Newsletter-No.45 (1974)

March 1974, No. 45 News from Rome: Pope Paul on Devotion to the Blessed Virgin --(p.1-2), Message to Missionaries from Propaganda Fide --(p.2-3) Works and Missions: Brazil, Nigeria, East Africa, Reunion, Mauritius, Bahamas, Puerto Rico, Cameroons, R.C.A. -- (p.4-11) Varia: Summer Courses in Belgium and France Bibliography --(p.12) Our Dead -- (p. 12

CSSP Newsletter-No.26 (1972)

March 1972, No. 26 News from Rome --(p.1) Provinces and Districts: Ireland, Portugal, Senegal, Nigeria, Kilimanjaro, U.S.A. East, Mexico, Sth. Brazil --(p. 2) Mission News: Cameroun, Congo, Zaïre, S. Africa, Trinidad, Amazonas --(p.7) Varia: African Theology, Latin America, Translations of the Bible, Our Dead -- (p. 10

CSSP Newsletter-No.35 (1973)

March 1973, No. 35 News from Rome: --(p.1 & 4) Generalate --(p.2) Provinces & Districts: Sénégal, Cameroons, Tanzania --(p.2-4) Missionary News: Latin-America, African Press, West Africa, Sénégal, Cameroons, Congo, Gabon, Zaire, Kenya, East Africa, Mauritius, Brazil, Tanzania --(p.4-11) Varia: Statistics of Catholic Church --(p.10) Our Dead: --(p.12

CSSP Newsletter-No.5 (1970)

February 1970, No. 5, Special Issue on East Central Nigeria Indictment: Commissioner of Police versus Lawrence Desmond O\u27Sullivan (m) -- (p. 1) Ihioma Mission; Diary of Events -- (p. 2) Christmas 1969 by Fr. Robert Eberhardt CSSp. -- (p. 5) Spiritans and the Last Days of Biafra --(p.6) Facts and Figures -- (p. 8) The Following is a Letter from Bishop G.E.I. Cockin to the Editor of the London Times -- (p. 10

CSSP Newsletter-No.7 (1971)

July 1971, No. 7 Spiritan Appointments: New Assistant General-Fr. Verdieu; Principal Superiors --(p.1) The General House: General Council - summer schedule of visits, Chapters, etc.; The 1972 Ordo --(p.4) News of the Provinces and Districts --(p.5) Rome and the Missionary world: The Synod: 1971; The Plenary Assembly of Propaganda Fide: 1972 --(p.8

CSSP Neewsletter-No.3 (1971)

March 1971, No. 3 Auxiliary Bishop appointed in Lokoja (Nigeria) --(p.1) Spiritan Apointments --(p.1) The General House: Superior General visits Angola; Spiritans join Sedos ; Meeting of Provincial Superiors --(p.1) News of the Provinces and Districts: A special report on Brazil, etc. --(p.2) News of the Missionary World --(p.9) Necrology --(p.10

CSSP Newsletter-No.41 (1973)

December 1973, No. 41 Generalate: Gen.Chap. 74; appointments; visits --(p.1-3) Provinces & Districts: England, France, USA East, Ontario, Senegal, Guinea(Mgr.Tchidimbo), Cameroons, Zaire, Angola, Kilimanjaro, Madagascar -- (p. 3-9) Mission News: West Indies, Latin America, Expansion of Islam --(p.9-11) Rome: Mission Survey, Prop. Fide College --(p.11-12) Our Dead: --(p.12