{"id":{"repo_id":"ohiolink","oai_identifier":"oai:etd.ohiolink.edu:ohiou1343698887"},"canonical_url":"https://search.dev.ndltd.org/etd/ohiolink/oai:etd.ohiolink.edu:ohiou1343698887","repository":{"repo_id":"ohiolink","name":"OhioLINK","base_url":"https://etd.ohiolink.edu/acprod/odb_etd/ws/oai/oai"},"display":{"title":"Spectral Variability Analysis of BL Lacertae","abstract":"BL-Lacertae is the prototype of BL Lac objects. It has been observed during the months of May, October and December 2011 with the aim of studying the intranight color variations on short timescales using the method of Color-Magnitude Diagram analysis and to look for the time-lag between the variations at different optical wavelengths using the method of Discrete Correlation Function analysis. Quasi-simultaneous measurements in the UBVRI bands have been performed using the 1.3 m optical telescope at MDM observatory at Kitt-Peak, AZ. A flare is observed during May 2011 in optical data that is also seen in the same time period in the gamma ray data, which is taken directly from the Fermi LAT website. BL Lacertae showed the trend Redder when Brighter and the transition to Bluer when brighter in the higher flux states, i.e. when the magnitude of R band is less than 13.5. A time-lag between the variations at optical wavelength band B and R is found to be (0.01 +/- 0.0056) day (less than 2ς). Using the value of time-lag, the lower limit on the magnetic field in the jet is found to be B > 1.24 G.","abstract_html":"BL-Lacertae is the prototype of BL Lac objects. It has been observed during the months of May, October and December 2011 with the aim of studying the intranight color variations on short timescales using the method of Color-Magnitude Diagram analysis and to look for the time-lag between the variations at different optical wavelengths using the method of Discrete Correlation Function analysis. Quasi-simultaneous measurements in the UBVRI bands have been performed using the 1.3 m optical telescope at MDM observatory at Kitt-Peak, AZ. A flare is observed during May 2011 in optical data that is also seen in the same time period in the gamma ray data, which is taken directly from the Fermi LAT website. BL Lacertae showed the trend Redder when Brighter and the transition to Bluer when brighter in the higher flux states, i.e. when the magnitude of R band is less than 13.5. A time-lag between the variations at optical wavelength band B and R is found to be (0.01 +/- 0.0056) day (less than 2ς). Using the value of time-lag, the lower limit on the magnetic field in the jet is found to be B > 1.24 G.","abstract_has_math":false,"creators":["Kohli, Meenakshi"],"institution":"Ohio University","degree_name":"Master of Science (MS)","degree_level":"masters","degree_discipline":"Physics and Astronomy (Arts and Sciences)","degree_department":null,"school":null,"contributors":["Elster, Charlotte","Boettcher, Markus"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2012,"date_issued":"2012","date_published":"2012","updated_at":"2026-07-24T03:35:52Z","subjects":["Physics","Spectral variability analysis of BL Lac","Spectral Energy Distribution","BL Lacertae"],"languages":["English"],"rights":["unrestricted","This thesis or dissertation is protected by copyright: all rights reserved. It may not be copied or redistributed beyond the terms of applicable copyright laws."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1343698887","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Elster, Charlotte","Boettcher, Markus"]},{"key":"dc:creator","label":"Author","values":["Kohli, Meenakshi"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2012"]},{"key":"dc:publisher","label":"Institution","values":["Ohio University / OhioLINK"]},{"key":"dc:type","label":"Dc Type","values":["Electronic Thesis or Dissertation"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Physics and Astronomy (Arts and Sciences)"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science (MS)"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Ohio University"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Physics","Spectral variability analysis of BL Lac","Spectral Energy Distribution","BL Lacertae"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["English"]},{"key":"dc:rights","label":"Dc Rights","values":["unrestricted","This thesis or dissertation is protected by copyright: all rights reserved. It may not be copied or redistributed beyond the terms of applicable copyright laws."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1343698887"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["BL-Lacertae is the prototype of BL Lac objects. It has been observed during the months of May, October and December 2011 with the aim of studying the intranight color variations on short timescales using the method of Color-Magnitude Diagram analysis and to look for the time-lag between the variations at different optical wavelengths using the method of Discrete Correlation Function analysis. Quasi-simultaneous measurements in the UBVRI bands have been performed using the 1.3 m optical telescope at MDM observatory at Kitt-Peak, AZ. A flare is observed during May 2011 in optical data that is also seen in the same time period in the gamma ray data, which is taken directly from the Fermi LAT website. BL Lacertae showed the trend Redder when Brighter and the transition to Bluer when brighter in the higher flux states, i.e. when the magnitude of R band is less than 13.5. A time-lag between the variations at optical wavelength band B and R is found to be (0.01 +/- 0.0056) day (less than 2ς). Using the value of time-lag, the lower limit on the magnetic field in the jet is found to be B > 1.24 G."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf","p.52","1.22 MB"]},{"key":"dc:title","label":"Title","values":["Spectral Variability Analysis of BL Lacertae"]}]}],"canonical_facts":{"dc:contributor":["Elster, Charlotte","Boettcher, Markus"],"dc:creator":["Kohli, Meenakshi"],"dc:date":["2012"],"dc:description":["BL-Lacertae is the prototype of BL Lac objects. It has been observed during the months of May, October and December 2011 with the aim of studying the intranight color variations on short timescales using the method of Color-Magnitude Diagram analysis and to look for the time-lag between the variations at different optical wavelengths using the method of Discrete Correlation Function analysis. Quasi-simultaneous measurements in the UBVRI bands have been performed using the 1.3 m optical telescope at MDM observatory at Kitt-Peak, AZ. A flare is observed during May 2011 in optical data that is also seen in the same time period in the gamma ray data, which is taken directly from the Fermi LAT website. BL Lacertae showed the trend Redder when Brighter and the transition to Bluer when brighter in the higher flux states, i.e. when the magnitude of R band is less than 13.5. A time-lag between the variations at optical wavelength band B and R is found to be (0.01 +/- 0.0056) day (less than 2ς). Using the value of time-lag, the lower limit on the magnetic field in the jet is found to be B > 1.24 G."],"dc:format":["application/pdf","p.52","1.22 MB"],"dc:identifier":["http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1343698887"],"dc:language":["English"],"dc:publisher":["Ohio University / OhioLINK"],"dc:rights":["unrestricted","This thesis or dissertation is protected by copyright: all rights reserved. It may not be copied or redistributed beyond the terms of applicable copyright laws."],"dc:subject":["Physics","Spectral variability analysis of BL Lac","Spectral Energy Distribution","BL Lacertae"],"dc:title":["Spectral Variability Analysis of BL Lacertae"],"dc:type":["Electronic Thesis or Dissertation"],"thesis:degree_discipline":["Physics and Astronomy (Arts and Sciences)"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science (MS)"],"thesis:institution_name":["Ohio University"]},"updated_at":"2026-07-24T03:35:52Z"}