CARNERERO MARTIN, Maria IsabelMaria IsabelCARNERERO MARTINRAITERI, Claudia MariaClaudia MariaRAITERIVILLATA, MassimoMassimoVILLATAAcosta Pulido, JoseJoseAcosta PulidoSmith, PaulPaulSmithLarionov, ValeriValeriLarionov2021-02-102021-02-1020162075-4434http://hdl.handle.net/20.500.12386/30298We investigate the multiwavelength behaviour of the high-energy peaked BL Lac object (HBL) Mrk 421 at redshift z = 0 . 031 in the period 2007-2015. We use optical photometric, spectroscopic, and polarimetric data and near-infrared data obtained by 35 observatories participating in the GLAST-AGILE Support Program (GASP) of the Whole Earth Blazar Telescope (WEBT), as well as by the Steward Observatory Support of the Fermi Mission. We also employ high-energy data from the Swift (UV and X-rays) satellite to study correlations among emission in different bands.ELETTRONICOenArticle10.3390/galaxies40400612-s2.0-85030699002000391004000029https://www.mdpi.com/2075-4434/4/4/61/htm2016Galax...4...61CFIS/05 - ASTRONOMIA E ASTROFISICA