Book contents
- Frontmatter
- Contents
- List of Illustrations
- Preface
- 1 Introduction
- 2 Early Research on Fission: 1933–1943
- 3 The Early Materials Program: 1933–1943
- 4 Setting Up Project Y: June 1942 to March 1943
- 5 Research in the First Months of Project Y: April to September 1943
- 6 Creating a Wartime Community: September 1943 to August 1944
- 7 The Gun Weapon: September 1943 to August 1944
- 8 The Implosion Program Accelerates: September 1943 to July 1944
- 9 New Hopes for the Implosion Weapon: September 1943 to July 1944
- 10 The Nuclear Properties of a Fission Weapon: September 1943 to July 1944
- 11 Uranium and Plutonium: Early 1943 to August 1944
- 12 The Discovery of Spontaneous Fission in Plutonium and the Reorganization of Los Alamos
- 13 Building the Uranium Bomb: August 1944 to July 1945
- 14 Exploring the Plutonium Implosion Weapon: August 1944 to February 1945
- 15 Finding the Implosion Design: August 1944 to February 1945
- 16 Building the Implosion Gadget: March 1945 to July 1945
- 17 Critical Assemblies and Nuclear Physics: August 1944 to July 1945
- 18 The Test at Trinity: January 1944 to July 1945
- 19 Delivery: June 1943 to August 1945
- Epilogue
- 20 The Legacy of Los Alamos
- Notes
- Name Index
- Subject Index
8 - The Implosion Program Accelerates: September 1943 to July 1944
Published online by Cambridge University Press: 31 March 2010
- Frontmatter
- Contents
- List of Illustrations
- Preface
- 1 Introduction
- 2 Early Research on Fission: 1933–1943
- 3 The Early Materials Program: 1933–1943
- 4 Setting Up Project Y: June 1942 to March 1943
- 5 Research in the First Months of Project Y: April to September 1943
- 6 Creating a Wartime Community: September 1943 to August 1944
- 7 The Gun Weapon: September 1943 to August 1944
- 8 The Implosion Program Accelerates: September 1943 to July 1944
- 9 New Hopes for the Implosion Weapon: September 1943 to July 1944
- 10 The Nuclear Properties of a Fission Weapon: September 1943 to July 1944
- 11 Uranium and Plutonium: Early 1943 to August 1944
- 12 The Discovery of Spontaneous Fission in Plutonium and the Reorganization of Los Alamos
- 13 Building the Uranium Bomb: August 1944 to July 1945
- 14 Exploring the Plutonium Implosion Weapon: August 1944 to February 1945
- 15 Finding the Implosion Design: August 1944 to February 1945
- 16 Building the Implosion Gadget: March 1945 to July 1945
- 17 Critical Assemblies and Nuclear Physics: August 1944 to July 1945
- 18 The Test at Trinity: January 1944 to July 1945
- 19 Delivery: June 1943 to August 1945
- Epilogue
- 20 The Legacy of Los Alamos
- Notes
- Name Index
- Subject Index
Summary
By late summer 1944, the implosion program was among the laboratory's highest priorities. It had started out as a small, informally run, back burner effort of a handful of researchers surrounding the reserved Seth Neddermeyer (Chapter 4). Between the fall of 1943 and the summer of 1944, it was transformed into a well-coordinated, multidisciplinary research effort of more than fourteen groups operating within T-Division and the newly created Gadget (G) and Explosives (X) Divisions.
The shift began with a visit in late September 1943 by the great mathematician and physicist John von Neumann. On learning about Neddermeyer's test implosions of small cylindrical metal shells, von Neumann pointed out that their efficiency could be increased using a substantially higher ratio of explosive to metal mass, which would promote more rapid assembly. The suggestion excited leading Los Alamos theorists, including Bethe, Oppenheimer, and Teller, who could now envision an atomic weapon requiring active material having less mass and a lower level of purity than was needed in the gun device – advantages of particular interest to General Groves.
Theorists, particularly Bethe and Teller, spent more and more time on implosion questions, while von Neumann continued to work on theoretical aspects of the implosion in Washington, D.C. The new implosion theory group was set up in March 1944 under Teller to develop the mathematical description of implosion. Additional experimentalists joined the program. Neddermeyer's E-Division group expanded from five to roughly fifty.
- Type
- Chapter
- Information
- Critical AssemblyA Technical History of Los Alamos during the Oppenheimer Years, 1943–1945, pp. 129 - 162Publisher: Cambridge University PressPrint publication year: 1993