{"id":{"repo_id":"creighton","oai_identifier":"oai:cdr.creighton.edu:10504/133683"},"canonical_url":"https://search.dev.ndltd.org/etd/creighton/oai:cdr.creighton.edu:10504/133683","repository":{"repo_id":"creighton","name":"Creighton University","base_url":"https://cdr.creighton.edu/server/oai/request"},"display":{"title":"ρ^' Photoproduction in ultra- peripheral heavy ion collisions with the ALICE detector","abstract":"This thesis presents the analysis of the coherent ρ' mesons photoproduction in ultra-peripheral Pb-Pb collisions at the center of mass energy of √(s_NN ) = 5.02 TeV with the ALICE detector at the Large Hadron Collider. The STAR collaboration has measured the π^+ π^- π^+ π^- decay channel previously in Au-Au collisions at a collision energy of 200 GeV and observed a wide peak at 1.540 GeV/c^2. In contrast, the Particle Data Group lists two separate particles at 1.465 GeV/c^2 and 1.720 GeV/c^2. I have measured the π^+ π^- π^+ π^- decay channel of the ρ' meson at a higher collision energy, with higher statistics to resolve this contradiction. I have analyzed 4.52 x 10^8 events. Out of that 1.46 x 10^4 events satisfied the selection criteria. The raw ρ' yield was approximately corrected for track reconstruction efficiency, but a full efficiency correction was not done. The detector acceptance was estimated using the STARlight Monte Carlo simulations. The efficiency-corrected ρ' mass distribution was fit with both a single Breit-Wigner function, to compare with the results obtained by the STAR collaboration and with a combination of two Breit-Wigner functions, as expected based on the Particle Data Group. The results I obtained favors the two Breit-Wigner interpretation, but this should be confirmed after doing a full efficiency correction","abstract_html":"This thesis presents the analysis of the coherent ρ' mesons photoproduction in ultra-peripheral Pb-Pb collisions at the center of mass energy of √(s_NN ) = 5.02 TeV with the ALICE detector at the Large Hadron Collider. The STAR collaboration has measured the π^+ π^- π^+ π^- decay channel previously in Au-Au collisions at a collision energy of 200 GeV and observed a wide peak at 1.540 GeV/c^2. In contrast, the Particle Data Group lists two separate particles at 1.465 GeV/c^2 and 1.720 GeV/c^2. I have measured the π^+ π^- π^+ π^- decay channel of the ρ' meson at a higher collision energy, with higher statistics to resolve this contradiction. I have analyzed 4.52 x 10^8 events. Out of that 1.46 x 10^4 events satisfied the selection criteria. The raw ρ' yield was approximately corrected for track reconstruction efficiency, but a full efficiency correction was not done. The detector acceptance was estimated using the STARlight Monte Carlo simulations. The efficiency-corrected ρ' mass distribution was fit with both a single Breit-Wigner function, to compare with the results obtained by the STAR collaboration and with a combination of two Breit-Wigner functions, as expected based on the Particle Data Group. The results I obtained favors the two Breit-Wigner interpretation, but this should be confirmed after doing a full efficiency correction","abstract_has_math":false,"creators":["Perera, Gamamedaliyanage Ann Shani"],"institution":"Creighton University","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Seger, Janet E."],"committee_chairs":[],"committee_members":[],"year":2021,"date_issued":"2021-08-05","date_published":"2021-08-05","updated_at":"2026-07-24T01:51:08Z","subjects":[],"languages":["en_US"],"rights":["Copyright is retained by the Author. A non-exclusive distribution right is granted to Creighton University and to ProQuest following the publishing model selected above."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/10504/133683","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Seger, Janet E."]},{"key":"dc:creator","label":"Author","values":["Perera, Gamamedaliyanage Ann Shani"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2021-08-13T21:15:31Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2021-08-13T21:15:31Z"]},{"key":"dc:date.issued","label":"Date","values":["2021-08-05"]},{"key":"dc:publisher","label":"Institution","values":["Creighton University"]},{"key":"dc:type","label":"Dc Type","values":["Dissertation"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en_US"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright is retained by the Author. A non-exclusive distribution right is granted to Creighton University and to ProQuest following the publishing model selected above."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10504/133683"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["This thesis presents the analysis of the coherent ρ' mesons photoproduction in ultra-peripheral Pb-Pb collisions at the center of mass energy of √(s_NN ) = 5.02 TeV with the ALICE detector at the Large Hadron Collider. The STAR collaboration has measured the π^+ π^- π^+ π^- decay channel previously in Au-Au collisions at a collision energy of 200 GeV and observed a wide peak at 1.540 GeV/c^2. In contrast, the Particle Data Group lists two separate particles at 1.465 GeV/c^2 and 1.720 GeV/c^2. I have measured the π^+ π^- π^+ π^- decay channel of the ρ' meson at a higher collision energy, with higher statistics to resolve this contradiction. I have analyzed 4.52 x 10^8 events. Out of that 1.46 x 10^4 events satisfied the selection criteria. The raw ρ' yield was approximately corrected for track reconstruction efficiency, but a full efficiency correction was not done. The detector acceptance was estimated using the STARlight Monte Carlo simulations. The efficiency-corrected ρ' mass distribution was fit with both a single Breit-Wigner function, to compare with the results obtained by the STAR collaboration and with a combination of two Breit-Wigner functions, as expected based on the Particle Data Group. The results I obtained favors the two Breit-Wigner interpretation, but this should be confirmed after doing a full efficiency correction"]},{"key":"dc:title","label":"Title","values":["ρ^' Photoproduction in ultra- peripheral heavy ion collisions with the ALICE detector"]}]}],"canonical_facts":{"dc:contributor.advisor":["Seger, Janet E."],"dc:creator":["Perera, Gamamedaliyanage Ann Shani"],"dc:date.accessioned":["2021-08-13T21:15:31Z"],"dc:date.available":["2021-08-13T21:15:31Z"],"dc:date.issued":["2021-08-05"],"dc:description.abstract":["This thesis presents the analysis of the coherent ρ' mesons photoproduction in ultra-peripheral Pb-Pb collisions at the center of mass energy of √(s_NN ) = 5.02 TeV with the ALICE detector at the Large Hadron Collider. The STAR collaboration has measured the π^+ π^- π^+ π^- decay channel previously in Au-Au collisions at a collision energy of 200 GeV and observed a wide peak at 1.540 GeV/c^2. In contrast, the Particle Data Group lists two separate particles at 1.465 GeV/c^2 and 1.720 GeV/c^2. I have measured the π^+ π^- π^+ π^- decay channel of the ρ' meson at a higher collision energy, with higher statistics to resolve this contradiction. I have analyzed 4.52 x 10^8 events. Out of that 1.46 x 10^4 events satisfied the selection criteria. The raw ρ' yield was approximately corrected for track reconstruction efficiency, but a full efficiency correction was not done. The detector acceptance was estimated using the STARlight Monte Carlo simulations. The efficiency-corrected ρ' mass distribution was fit with both a single Breit-Wigner function, to compare with the results obtained by the STAR collaboration and with a combination of two Breit-Wigner functions, as expected based on the Particle Data Group. The results I obtained favors the two Breit-Wigner interpretation, but this should be confirmed after doing a full efficiency correction"],"dc:identifier.uri":["http://hdl.handle.net/10504/133683"],"dc:language.iso":["en_US"],"dc:publisher":["Creighton University"],"dc:rights":["Copyright is retained by the Author. A non-exclusive distribution right is granted to Creighton University and to ProQuest following the publishing model selected above."],"dc:title":["ρ^' Photoproduction in ultra- peripheral heavy ion collisions with the ALICE detector"],"dc:type":["Dissertation"]},"updated_at":"2026-07-24T01:51:08Z"}