The feasibility of utilizing characteristic interactions of K2\u00b0 mesons in the liquid of a CF3Br bubble chamber for the purpose of detecting photoproduced K\u00b0 mesons has been investigated. The K2\u00b0 mesons were produced from carbon at an average laboratory angle of 11 degrees by photons with energies ranging from threshold to 1300 Mev. Although examples of most of the possible K2\u00b0 signatures were found, only the signature comprised of a [...] decay could be used to estimate the cross sections for photoproducing K\u00b0 mesons in conjunction with [...] and [...] hyperons. If the CM cross sections for the three processes are comparable in magnitude, the average differential CM cross sections are estimated to be (0.36 +/- 0.19) x 10(-30) cm2/ster. Since an enormous amount of work is required per K2\u00b0 detected, this technique is not recommended for more detailed examination of K\u00b0 photoproduction unless simpler methods cannot be devised.
\r\n\r\nAn auxiliary result, the thermodynamic conditions of the bubble chamber have been shown to be well stabilized over long periods of time. For this reason, measurements of the gap-length distribution of a track may be used to determine a particle\u2019s velocity without recalibration for each individual bubble chamber expansion.
", "doi": "10.7907/QM7F-G944", "publication_date": "1962", "thesis_type": "phd", "thesis_year": "1962" }, { "id": "thesis:662", "collection": "thesis", "collection_id": "662", "cite_using_url": "https://resolver.caltech.edu/CaltechETD:etd-02172006-111450", "primary_object_url": { "basename": "Mullins_jh_1959.pdf", "content": "final", "filesize": 29629471, "license": "other", "mime_type": "application/pdf", "url": "/662/1/Mullins_jh_1959.pdf", "version": "v2.0.0" }, "type": "thesis", "title": "Part I: A WF\u2086 Bubble Chamber. Part II: Physics of Bubble Chambers and Applications to Advanced Designs", "author": [ { "family_name": "Mullins", "given_name": "Joe Hill", "clpid": "Mullins-Joe-Hill" } ], "thesis_advisor": [ { "family_name": "Bacher", "given_name": "Robert F.", "clpid": "Bacher-R-F" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_pma" } ], "abstract": "Part I: \r\n\r\nThe role of bubble chambers in photoproduction studies is considered in the light of experimental problems, and arguments for use of heavy liquid chambers are presented. Successful operation of a small WF6 chamber in conjunction with the C.I.T. electron synchrotron is described and experimental results are given. Design, construction and operation of a 12 inch hydrostatically supported bubble chamber for use with hydrocarbons, Freons, or WF6 is described. The chamber is operated with a unique \"resonant\" expansion system employing large valves of a special design, resulting in a very fast operating cycle with small energy input.\r\n\r\nPart II: \r\n\r\nThe mechanism of formation and growth of bubbles in a bubble chamber is investigated, and the results of calculations concerning growth and collapse in propane are given. Mechanisms which have been proposed dealing with the nucleation of bubbles by charged particles are examined with the intention of determining their probable validity, and the influence of some additional processes is discussed. A technique is suggested which may allow construction of large bubble chambers, particularly of the heavy liquid variety, with very fast expansions and recompressions, or very rapid cycling rates.", "doi": "10.7907/JNK9-EQ20", "publication_date": "1959", "thesis_type": "phd", "thesis_year": "1959" }, { "id": "thesis:1090", "collection": "thesis", "collection_id": "1090", "cite_using_url": "https://resolver.caltech.edu/CaltechETD:etd-03242004-143552", "primary_object_url": { "basename": "Jacobson_nf_1956.pdf", "content": "final", "filesize": 6590392, "license": "other", "mime_type": "application/pdf", "url": "/1090/1/Jacobson_nf_1956.pdf", "version": "v2.0.0" }, "type": "thesis", "title": "Studies in the Measurement of Nuclear Radiations of Extremely Low Intensity - Carbon 14 Dating", "author": [ { "family_name": "Jacobson", "given_name": "Norman Ford", "clpid": "Jacobson-Norman-Ford" } ], "thesis_advisor": [ { "family_name": "Yost", "given_name": "Don M.", "clpid": "Yost-D-M" }, { "family_name": "Neher", "given_name": "Henry Victor", "clpid": "Neher-H-V" }, { "family_name": "Bacher", "given_name": "Robert F.", "clpid": "Bacher-R-F" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_chem" } ], "abstract": "The technical details of a radiation measuring system based on a quartz torsion fiber electroscope and a pressurized ionization chamber are described. This equipment is designed to measure the radiation intensity from the carbon-14 contained in a sample introduced into the system as carbon dioxide. This system, including the shielding, is shown to be capable of measuring nuclear radiations of extremely low intensities, on the order of 1/200 of the normal laboratory background level, with a probable error of approximately l%. The background radiation intensity observed with the system including the shielding is also on the order of 1/200 of the normal laboratory background level. The nature of background radiation and its relation to the measurement of such low intensities is discussed. It is shown that the main limitation in accuracy, with the equipment described here, is due to cosmic ray bursts. It is also shown that the major source of background radiation is external to the equipment, being thus due to cosmic rays and/or local external gamma ray emitting material contamination. Although the evidence is not conclusive, the data indicates in addition that the cosmic rays are the major contributor to this background radiation. The main conclusion which may be drawn from these results is that the selection of an equipment location is very effective in reducing the level of background radiation, thus permitting the measurement of radiation fields of extremely low intensity. The final application of this equipment was to the well known carbon-14 dating method originated by W. F. Libby. Several samples of interest were dated and the results are given. Of particular interest, are the samples from the Santa Rosa Islands off the California Coast, concerning an Indian culture which existed there before Christ and after.", "doi": "10.7907/M68S-AP25", "publication_date": "1956", "thesis_type": "phd", "thesis_year": "1956" } ]