Page 41 - Neutrons for Sciences and Society

Chapter 2: Portrait of three founders of the ILL
There he had to borrow books from the library of the Lycee du Parc. A roundup there forced him to hide far from Lyon up to the Liberation32. Like his father he managed to escape the anti-Jewish raids, but his mother was arrested by the Vichy police and was deported to Auschwitz where she was murdered. He had to await the Liberation to continue his studies, firstly as a foreign student, until his naturalisation in November 1945, too late to enter the prestigious School of Mines to which he had already qualified.
After the war and leaving university in 1946 he was taken on
by the CEA. His first job was to reconstruct the calculations
for atomic piles (to help in the design of ZOE) from the notes brought back from America by Kowarski33. The following year
he departed for Denmark to train in theoretical physics with
Niels Bohr. On his return he was attached to the department of mathematical physics led by Jacques Yvon. The scientists in this group, (Anatole Abragam, Michel Trocherie, then Albert Messiah, Claude Bloch, and others) shared their time between theoretical physics and reactor physics. The theoretical work of Horowitz focused on a variety of topics. In 1949 he wrote up an important clarification with Albert Messiah on the passage of neutrons through crystalline media34. I regret I have not been able to find the actual text35, but the subject shows that at this time he was interested in what would be the main theme of research at the ILL.
32 The books disappeared during this flight. The Lycée du Parc lodged a complaint and Horowitz was convicted of theft by a court of the regime. After the Liberation he found himself with this criminal record which the new Justice Ministry refused to annul. I learnt these facts from Robert Dautray, and offer him my thanks. They dem- onstrate well the attitude of the French authorities at that time towards the Jews.
33 “Souvenirs de Jules Horowitz” published in a special edition of “Echos du CEA” after 20 years of ZOE.
34 See the book “L’oeuvre de Jules Horowitz” Tome 1, page 48. [2018 addition: Book edited by Lucile Arnau- det, Robert Deloche and Lucien Procope, Paris, CEA, 1999. The paper of 1949 is in a hard-to-find CEA report “Horowitz J. et Messiah A., Rapport SPM no 5”. SPM stands for “Service de Physique Mathématique”].
35 I think I possess copies of all the articles used in this draft. They cover the effects of scattering and polarised neutrons. These copies have been heavily annotated. Comparisons with manuscripts from that time show these comments were written by Horowtiz.
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