PURPOSE.

The objective of this document is to provide a guide to all the nuclear weapon effects data acquired during U.S. atmospheric nuclear explosions.

The nuclear effects data acquired from U.S. atmospheric nuclear weapon detonations during 1945 to 1962 have been maintained and used for decades. In fact, the judicious application of these data has been instrumental in the development of a strong defense posture by the United States. As the immediate need for this information decreases, the interest in preserving it could diminish. Likewise, the ability to use it will erode, especially since many of the primary data users were the data generators, and they are now at retirement age. The Defense Nuclear Agency (DNA) is taking steps to assure that the data will still be available in the future if unforeseen threats arise, once again requiring the United States to take a strong nuclear weapon stand. As an adjunct to the nuclear effects data preservation it is appropriate to provide a guide to future users who will not have access to current experts to tell them where data can be found. This document is designed to provide such guidance and to serve in part. as a replacement for the corporate memory that exists today.

NUCLEAR WEAPON EFFECTS.

The "Guide to Atmospheric Nuclear Weapon Effects Data" contains no nuclear weapon test data. It does identify essentially all of the atmospheric nuclear weapon effects projects that were fielded during U.S.-sponsored events from 1945 to 1962 and specifies the document where data can be found. Effects data is that information that describes how the explosion's radiant emissions and induced hydrodynamic motions and induced electromagnetic fields affect materials and objects. Nuclear weapon effects are descriptions of the bomb's destructive powers. The agents of these powers; airblast. ground shock, thermal and some of the nuclear radiation, and electromagnetic pulse (EMP) are themselves largely products of the explosion's interactions with its primary environment. Experiments that measured these destructive agents are also described in this guide as these are important in understanding the effects. Not included are the small number of x-ray effects experiments conducted in conjunction with the completely contained underground nuclear tests that took place in the last years of the atmospheric testing era.

Experiments intended to check the performance of the nuclear explosive device itself usually called weapon diagnostics or bomb physics measurements are generally not included unless they provide nuclear environment information useful for weapon effects analyses. This distinction is sometimes difficult to make and this guide errs on the side of inclusion.

ATMOSPHERIC NUCLEAR TESTS.

The U.S. nuclear detonations used as sources for atmospheric nuclear effects data in this document were not all atmospheric explosions. Some were underwater bursts and others were exoatmospheric detonations. A few were underground cratering tests. This document describes effects activities from all detonations even underground tunnels and shaft tests where the objective was to collect DoD effects data except for x-ray effects. This exclusion is noted and explained in discussing the 1958 Hardtack II series. With one exception, safety-related tests are not included since they provided no effects data. Trinity and the Hiroshima and Nagasaki bombings are

included because the bombings provided unique effects information, although the diagnostics associated with normal nuclear weapon effects tests were not available.

The majority of the U.S. atmospheric nuclear tests were for weapon development, not for effects data. However effects information was frequently acquired on development tests on a noninterference basis.

The atmospheric nuclear testing period is generally considered to span the period from 1945, when the Trinity detonation occurred, to 1963, when the atmospheric nuclear test ban came into force. The final U.S. atmospheric nuclear test actually occurred in 1962. The vast majority of U.S. atmospheric tests occurred before the 1958 test moratorium. A relatively small number took place between April and November 1962, after the Soviets broke the first moratorium and before the atmospheric testing ended with the 1963 Treaty.

The dates listed for the nuclear explosions are local rime where the events took place. Many tests in the Pacific occurred one day earlier than the date in the United States.

REPORT ORGANIZATION.

In order to meet the objective of this project, it was necessary to search out, review, and synopsize every document that was used as a record for U.S. atmospheric nuclear weapon effects data. U.S. test directors were thorough in project organization and reporting from the outset of nuclear testing. Each project was assigned a project number or name and a report number Test summary documents containing project numbers and descriptions were generated. (With this identification process and a complete library, data document review became routine if time consuming.)

Atmospheric nuclear weapon effects data sources are reported in this document in chronological order of the nuclear events or test series (see Table 1). That is. effects data sources for the Trinity tests (July 1945) are presented first, Hiroshima and Nagasaki (August 1945) second. Operation Crossroads (1946) third, Operation Sandstone (1948) fourth, etc.

U.S. test series were typically organized as "operations" with various numbers of nuclear detonations occurring at one of the test sites over a period of weeks or months. These operations were like a campaign with a commander or director, a supporting organization and limited objectives.

The form of two of the operation's name has been altered over the years since first used. In 1958 the test operations in the Pacific were called Operation Hardtack and the small operation at NTS that followed was called Operation Hardtack II. Similarly, the 1962 test operation in the Pacific were called Operation Dominic and the smaller NTS operations were called Operation Sunbeam and Operation Dominic II. In neither case was the main show in the Pacific called Hardtack I or Dominic I in the contemporaneous literature. As this report is essentially an index to this contemporaneous literature, these "I" are not used.

Within each operation, a number of effects programs might be defined, with each programs identifying a technical area of interest, such as blast effects, thermal effects, aircraft structure effects, etc. Within each program, a number of projects would be performed in support of the program. Each program was assigned a number (e.g., Program 1, Blast Effects), and each project within that program contained the program number prefix (e.g., Project 1.1, Peak Pressure TableMeasurements). Generally, each technical area was assigned the same program number for all of the operations. That is, Program I involved blast studies in Operation Castle, Operation Redwing, etc. Thus, a researcher wishing to determine what atmospheric effects experiments were

performed in the area of blast should review the Program 1 projects in each of the operations. While this effects program format was not adhered to for all atmospheric test operations, it was followed the majority of the time.

The weapon test literature was organized in 1951 into a single numerical array that continues to be used for reporting nuclear weapon effects experiments. WT-1 (for Weapon Test report no.1) through WT-120 were assigned to the Operation Greenhouse experiments and the WT reports in the 200 block were assigned to Ranger in the same year. Each successive test operation was assigned a block of 100 or 200 WT numbers that the projects within the formal test organization used for reporting. An exception to the blocking of reports by hundreds occurred in 1958 when Argus was given a small block within the WT-1700 block being used by the simultaneously occurring Hardtack operation. In addition, a small block of very high numbers (WT 9000) were assigned for several reports of multiple series measurements.

In later years, this blocking by centuries of report numbers broke down even further and when the United States returned to atmospheric testing in 1961 the reports began being designated as "Project Officer's Reports" or POR, although the numbering continued whether they were WT or POR. For some operations, the project reports have been published as either WT or POR, and indeed some reports have both WT and POR designations. In addition, interim reports may have been issued by the projects as ITR (for Interim Test Reports) and POIR (for Project Officer's Interim Reports). These used the same number as that assigned to the project's WT or POR, and although most of these interim reports have been superseded by final reports, some are the only report issued by the project and are considered as final.

For test series before Ranger and Greenhouse, namely Crossroads and Sandstone, an arbitrary numbering scheme was set up for the already published body of the test literature from these series. The 214 reports of Crossroads were designated XRD-1 through XRD-214 and for Sandstone the reports became SS-l through 55-44. These were post-publication designations and do not appear printed on the covers of the documents, but because of the limited availability of these older reports this post-publication numbering scheme appears to have worked. if agencies hold these old documents, they seem to know them by these XRD and 55 numbers.

Weapon effects data derived from the proof test of the implosion device at Trinity or from the attacks upon Japan are largely in the reports of the laboratory at Los Alamos (now LANL). There are also other agency reports that are, for a few experimental activities, the prime place of data publication. These sources are cited when appropriate.

An introduction to each section of this guide provides an historical background and describes the objectives of the test series, the types of nuclear weapons under development, the types of weapon effects data acquired with associated program numbers, and any other information deemed useful to atmospheric nuclear weapon effects users.

Following the introduction, each program and its associated projects are briefly described in terms of objective, instrumentation employed, and type of data reported. The title and the identification number for the report containing the data are provided. The some cases, the quality and quantity of data are indicated. Projects and reports providing no data usually have been omitted from this document.

Each test operation included various experimental, diagnostic and support activities. These activities were assigned program numbers for organization and reporting purposes. In most cases. the Department of Defense DoD) effects experiments were incorporated in Programs 1 through 9. Some test series included effects investigations by the Atomic Energy Commission (AEC) and by the Federal Office of Civil Defense, which were not reported within Programs 1 through 9. These projects and data sources are described in this document, usually being added to the appropriate DoD effects area or in a section entitled "Non-DOD Effects Projects."

Practically all of the data reports identified in this document were originally classified. This is to be expected, considering the state of knowledge of nuclear weapons and effects in the 1940s and 1950s. A large number of the reports have since been declassified.

Essentially all of the atmospheric nuclear weapon effects data documents and a large quantity of nuclear test film data reside at the DoD Nuclear Information and Analysis Center DASIAC), Santa Barbara, CA, operated by Kaman Sciences Corporation for DNA. An additional number of relevant AEC environment and effects reports may exist at Department of Energy (DOE) facilities.