Collisions of Neutrons with Protons

Abstract

where T is the period. The value n n determines the coefficient of refraction n of electromagnetic waves in a ferromagnetic metal, while nk determines their coefficient of absorption 3 k: n=(<rTfj, n )% and &= (<r 7)^)2.In practice M& is usually calculated from the resistance of ferromagnetic wires to an alternating current and i* n jo X toocm from their self-induction. The values fik, defined by me, were calculated from the resistance determined from the coefficient of absorption of waves in parallel wires. In another paper 4 I determined the magnetic permeability by a method which consisted in comparing the coefficient of reflection of the waves from a coarse Hertzian grating of magnetic wires, with the coefficient of reflection from a grating of non-magnetic wires of the same diameter and resistance. This method allows one to calculate the value of fx n and to compare it with nk obtained by the method of absorption of the waves in wires. 3 The results observed by me for X between 1 and 73 cm for a wire 0.0245 mm in diameter, are shown by circles in Fig. 1. The values of fi n obtained by Hoag and Jones are shown by crosses. They relate to a wire 3.18 mm in diameter. The concordance of the results of Hoag and Jones with my values is better than expected. We see from the above, that the values obtained by them for \x n were bound to be smaller than my values for /**•. We see also, that the permeability of iron really decreases, approaches 1 at \ = 1 cm, and approaches the value corresponding to thermal and optical frequencies.W. ARKADIEW Langer 1 has recently demonstrated that Be 9 is radioactive and has suggested the possibility that He 5 might be one of the products of the disintegration and that, if so, He 5 should be found in old beryllium mineral.Professor Gruner placed at our disposal a large crystal of beryl from the pre-Cambrian dykes of the Black Hills in South Dakota (estimated age greater than 3X10 8 years). The gases were driven out by heating the crushed crystal and were passed through a charcoal trap immersed 1 R. M. Langer and R. W. Raitt, Phys. Rev. 43, 585 (1933).in liquid air. A mass-spectrograph analysis of the gas not absorbed showed He 4 . If He 5 was present its concentration was less than one part in 40,000 relative to He 4 .As a check on the apparatus, ordinary hydrogen was examined for the (H 2 H J ) + molecular ion. An analysis of the data, taken at different pressures to correct for (H3 1 )" 1 ", showed H 2 present in a concentration of the order of 1 part in 30,000 relative to H 1 .

The early history of carbon-14

“…By Volume 40, Number the end of 1936,1 received a PhD on the basis of results obtained from an analysis of 730 tracks which showed a marked asymmetry in the angular distribution of protons in the energy range from ~0.1 to 3 Mev (9). This result confirmed those obtained by Kurie a few years previously (10). But, at the time, these results were in contradiction to theoretical expectations.…”

Neutron-Proton Collisions

“…The model of neutron of a complex particle, proton-electron combination, used by Massey in its calculations seems to be in disagreement with some experimental observations (see for example [7], [8], [28]).…”

Нейтрон

“…Иногда, однако, на долю нейтрона при-ходится вся энергия, и такой процесс соответствует испусканию быстрых нейтронов. С этой точки зрения мы должны получить остаточные ядра С 12 , состоящие из трех α-частиц, и две группы нейтронов, которые должны были бы различаться по энергии на величину энергии γ-лучей (с поправкой на кинетическую энергию отброшенного ядра С 12 ). Если принять для скоростей двух групп нейтронов значения, данные выше, энергия γ-лучей получится рав-ной 7 · 10 е электрон-вольт.…”

“…Однако нет оснований тогда ожидать испускания нейтронов двумя определен-ными группами, как это, повидимому, происходит. Может быть имеют место оба процесса, причем иногда образуется ядро С 12 , а иногда три α-частицы; тогда должно быть принято в расчет при-сутствие γ-лучей не только с энергией около 7 • 10 а V, но *1и 5· 10 6 V, как это получается из измерений Беккера и Боте.…”

“…Некоторые данные, касающиеся углового распределения прото-нов, были получены этим методом Оже и Моно-Герценом , а также американским физиком Кюри 12 , который пользовался несколько иной методикой. В обоих опытах источником нейтронов служил бе-риллий, массивный слой которого подвергался бомбардировке α-ча-стиц полония.…”