Spectral Variability Analysis of BL Lacertae

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.

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Physics and Astronomy (Arts and Sciences)

Grantor dc:publisher

Ohio University

Year dc:date

2012

Author dc:creator

• Kohli, Meenakshi

Contributors dc:contributor

• Elster, Charlotte
• Boettcher, Markus

• Physics
• Spectral variability analysis of BL Lac
• Spectral Energy Distribution
• BL Lacertae

Statement 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.

Language dc:language

English

Repository record dc:identifier

http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1343698887

OAI identifier oai:identifier

oai:etd.ohiolink.edu:ohiou1343698887