{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/23962"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/23962","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Photoproduction of charged pions from deuterium near threshold","abstract":"\"An experiment has been performed in order to improve existing information on the behavior of the pi-photoproduction cross section near threshold. To do this an X=ray beam from the University of Illinois betatron was passed through a 14 inch liquid deuterium bubble chamber. Each X ·-ray pulse (E max :: 230 MeV) contained a total energy of about 106 MeV. l'ne X.\"\"ray beam wa.s hardened by means of a. standard beam . hardening technique to reduce the electron background. The X-ray beam monitor was calibrated with an uncertainty of ± 2.4%. A total of 140,000 usable photographs were taken. About 5400 .\"\" + ~ -photoproduction events and about 2700 ~ Qphotoproduction events were found. Each ~=-event was identified by a kinematic fitting of the vertex, and each n+=event was identified by a characteristic ~= ~ decay signature. Results were compared with Baldin9s impulse approximation calculations in order to obtain the matrix element for the ~=-photoproduction process from a free neutron. The results agree with the previous experiment by Adamovich et al. and with the photoproduction theory of Chew, Goldberger$ Low and Nambu. This result, however, was found to be sensitive to the so-called Ucut~offgD parameter. The .., + . ~ to ~ ratio has been dete~ned for seven pion laboratory energy and angle binsp using the ~+~events observed in deuterium. Coulomb corrections have been applied to these results. A. Chew=Low ti8unstable tar get ei extrapolation procedure was used in order to obtain the cross section for the ~=-photoproduction process from a free neutron. A. correction factor has been calculated to eliminate the effects of the Coulomb interaction and specific n~clear force interaction of the recoiling protons in the final state. The result of this analysis agrees with the CGLN theory evaluated with a coupling constant f 2= 0.·073 (=) ~ .003 and N being set to zero. The extrapolation to threshold was carried out using the cross section shape predicted by CGLN. The threshold value of BRa 0 ( .., ) Ci was found to be 26.0! 1.0 ~b/ster. Comparing th~s with the result of the latest ~ + experiment a't the University of Illinoisp the threshold t;J' -/t;+J' ratio was found to be 1.23 + .06.\"","abstract_html":""An experiment has been performed in order to improve existing information on the behavior of the pi-photoproduction cross section near threshold. To do this an X=ray beam from the University of Illinois betatron was passed through a 14 inch liquid deuterium bubble chamber. Each X ·-ray pulse (E max :: 230 MeV) contained a total energy of about 106 MeV. l'ne X.""ray beam wa.s hardened by means of a. standard beam . hardening technique to reduce the electron background. The X-ray beam monitor was calibrated with an uncertainty of ± 2.4%. A total of 140,000 usable photographs were taken. About 5400 ."" + ~ -photoproduction events and about 2700 ~ Qphotoproduction events were found. Each ~=-event was identified by a kinematic fitting of the vertex, and each n+=event was identified by a characteristic ~= ~ decay signature. Results were compared with Baldin9s impulse approximation calculations in order to obtain the matrix element for the ~=-photoproduction process from a free neutron. The results agree with the previous experiment by Adamovich et al. and with the photoproduction theory of Chew, Goldberger$ Low and Nambu. This result, however, was found to be sensitive to the so-called Ucut~offgD parameter. The .., + . ~ to ~ ratio has been dete~ned for seven pion laboratory energy and angle binsp using the ~+~events observed in deuterium. Coulomb corrections have been applied to these results. A. Chew=Low ti8unstable tar get ei extrapolation procedure was used in order to obtain the cross section for the ~=-photoproduction process from a free neutron. A. correction factor has been calculated to eliminate the effects of the Coulomb interaction and specific n~clear force interaction of the recoiling protons in the final state. The result of this analysis agrees with the CGLN theory evaluated with a coupling constant f 2= 0.·073 (=) ~ .003 and N being set to zero. The extrapolation to threshold was carried out using the cross section shape predicted by CGLN. The threshold value of BRa 0 ( .., ) Ci was found to be 26.0! 1.0 ~b/ster. Comparing th~s with the result of the latest ~ + experiment a't the University of Illinoisp the threshold t;J' -/t;+J' ratio was found to be 1.23 + .06."","abstract_has_math":false,"creators":["Yoon, Taek-Soon"],"institution":null,"degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Physics","degree_department":null,"school":null,"contributors":["Goldwasser, E.L."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-19T15:08:53Z","date_published":"2011-05-19T15:08:53Z","updated_at":"2026-07-22T22:25:23Z","subjects":["photoproduction","charged pions","deuterium","deuterium near threshold","liquid deuterium bubble chamber"],"languages":["en"],"rights":["1964 Taek-Soon Yoon"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["2820769"],"render_values":[{"text":"2820769","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/23962","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Goldwasser, E.L."]},{"key":"dc:creator","label":"Author","values":["Yoon, Taek-Soon"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-19T15:08:53Z","10000-01-01","1964"]},{"key":"dc:type","label":"Dc Type","values":["Dissertation / Thesis","text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Physics"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["photoproduction","charged pions","deuterium","deuterium near threshold","liquid deuterium bubble chamber"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["1964 Taek-Soon Yoon"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["2820769","http://hdl.handle.net/2142/23962"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["\"An experiment has been performed in order to improve existing information on the behavior of the pi-photoproduction cross section near threshold. To do this an X=ray beam from the University of Illinois betatron was passed through a 14 inch liquid deuterium bubble chamber. Each X ·-ray pulse (E max :: 230 MeV) contained a total energy of about 106 MeV. l'ne X.\"\"ray beam wa.s hardened by means of a. standard beam . hardening technique to reduce the electron background. The X-ray beam monitor was calibrated with an uncertainty of ± 2.4%. A total of 140,000 usable photographs were taken. About 5400 .\"\" + ~ -photoproduction events and about 2700 ~ Qphotoproduction events were found. Each ~=-event was identified by a kinematic fitting of the vertex, and each n+=event was identified by a characteristic ~= ~ decay signature. Results were compared with Baldin9s impulse approximation calculations in order to obtain the matrix element for the ~=-photoproduction process from a free neutron. The results agree with the previous experiment by Adamovich et al. and with the photoproduction theory of Chew, Goldberger$ Low and Nambu. This result, however, was found to be sensitive to the so-called Ucut~offgD parameter. The .., + . ~ to ~ ratio has been dete~ned for seven pion laboratory energy and angle binsp using the ~+~events observed in deuterium. Coulomb corrections have been applied to these results. A. Chew=Low ti8unstable tar get ei extrapolation procedure was used in order to obtain the cross section for the ~=-photoproduction process from a free neutron. A. correction factor has been calculated to eliminate the effects of the Coulomb interaction and specific n~clear force interaction of the recoiling protons in the final state. The result of this analysis agrees with the CGLN theory evaluated with a coupling constant f 2= 0.·073 (=) ~ .003 and N being set to zero. The extrapolation to threshold was carried out using the cross section shape predicted by CGLN. The threshold value of BRa 0 ( .., ) Ci was found to be 26.0! 1.0 ~b/ster. Comparing th~s with the result of the latest ~ + experiment a't the University of Illinoisp the threshold t;J' -/t;+J' ratio was found to be 1.23 + .06.\"","Submitted by Carolyn Mead (cmead2@illinois.edu) on 2011-05-19T15:08:53Z No. of bitstreams: 1 1964_yoon.pdf: 3381171 bytes, checksum: 880dd847b465c2310d3b3c632d15b8bf (MD5)","Made available in DSpace on 2011-05-19T15:08:53Z (GMT). No. of bitstreams: 1 1964_yoon.pdf: 3381171 bytes, checksum: 880dd847b465c2310d3b3c632d15b8bf (MD5) Previous issue date: 1964","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Carolyn Mead (cmead2@illinois.edu) on 2011-05-19T15:08:53Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:13:44-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: Thesis","Thesis","U of I Only"]},{"key":"dc:title","label":"Title","values":["Photoproduction of charged pions from deuterium near threshold"]}]}],"canonical_facts":{"dc:contributor":["Goldwasser, E.L."],"dc:creator":["Yoon, Taek-Soon"],"dc:date":["2011-05-19T15:08:53Z","10000-01-01","1964"],"dc:description":["\"An experiment has been performed in order to improve existing information on the behavior of the pi-photoproduction cross section near threshold. To do this an X=ray beam from the University of Illinois betatron was passed through a 14 inch liquid deuterium bubble chamber. Each X ·-ray pulse (E max :: 230 MeV) contained a total energy of about 106 MeV. l'ne X.\"\"ray beam wa.s hardened by means of a. standard beam . hardening technique to reduce the electron background. The X-ray beam monitor was calibrated with an uncertainty of ± 2.4%. A total of 140,000 usable photographs were taken. About 5400 .\"\" + ~ -photoproduction events and about 2700 ~ Qphotoproduction events were found. Each ~=-event was identified by a kinematic fitting of the vertex, and each n+=event was identified by a characteristic ~= ~ decay signature. Results were compared with Baldin9s impulse approximation calculations in order to obtain the matrix element for the ~=-photoproduction process from a free neutron. The results agree with the previous experiment by Adamovich et al. and with the photoproduction theory of Chew, Goldberger$ Low and Nambu. This result, however, was found to be sensitive to the so-called Ucut~offgD parameter. The .., + . ~ to ~ ratio has been dete~ned for seven pion laboratory energy and angle binsp using the ~+~events observed in deuterium. Coulomb corrections have been applied to these results. A. Chew=Low ti8unstable tar get ei extrapolation procedure was used in order to obtain the cross section for the ~=-photoproduction process from a free neutron. A. correction factor has been calculated to eliminate the effects of the Coulomb interaction and specific n~clear force interaction of the recoiling protons in the final state. The result of this analysis agrees with the CGLN theory evaluated with a coupling constant f 2= 0.·073 (=) ~ .003 and N being set to zero. The extrapolation to threshold was carried out using the cross section shape predicted by CGLN. The threshold value of BRa 0 ( .., ) Ci was found to be 26.0! 1.0 ~b/ster. Comparing th~s with the result of the latest ~ + experiment a't the University of Illinoisp the threshold t;J' -/t;+J' ratio was found to be 1.23 + .06.\"","Submitted by Carolyn Mead (cmead2@illinois.edu) on 2011-05-19T15:08:53Z No. of bitstreams: 1 1964_yoon.pdf: 3381171 bytes, checksum: 880dd847b465c2310d3b3c632d15b8bf (MD5)","Made available in DSpace on 2011-05-19T15:08:53Z (GMT). No. of bitstreams: 1 1964_yoon.pdf: 3381171 bytes, checksum: 880dd847b465c2310d3b3c632d15b8bf (MD5) Previous issue date: 1964","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Carolyn Mead (cmead2@illinois.edu) on 2011-05-19T15:08:53Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:13:44-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: Thesis","Thesis","U of I Only"],"dc:identifier":["2820769","http://hdl.handle.net/2142/23962"],"dc:language":["en"],"dc:rights":["1964 Taek-Soon Yoon"],"dc:subject":["photoproduction","charged pions","deuterium","deuterium near threshold","liquid deuterium bubble chamber"],"dc:title":["Photoproduction of charged pions from deuterium near threshold"],"dc:type":["Dissertation / Thesis","text"],"thesis:degree_discipline":["Physics"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."]},"updated_at":"2026-07-22T22:25:23Z"}