Exploring the Magnetic Field Configuration in BL Lac Using GMVA

The high radio frequency polarization imaging of non-thermal emission from active galactic nuclei (AGN) is a direct way to probe the magnetic field strength and structure in the immediate vicinity of supermassive black holes (SMBHs) and is crucial in testing the jet-launching scenario. To explore the the magnetic field configuration at the base of jets in blazars, we took advantage of the full polarization capabilities of the Global Millimeter VLBI Array (GMVA). With an angular resolution of ∼50 micro-arcseconds (μas) at 86 GHz, one could resolve scales up to ∼450 gravitational radii (for a 10 9 solar mass black hole at a redshift of 0.1). We present here the preliminary results of our study on the blazar BL Lac. Our results suggest that on sub-mas scales the core and the central jet of BL Lac are significantly polarized with two distinct regions of polarized intensity. We also noted a great morphological similarity between the 7 mm/3 mm VLBI images at very similar angular resolution.

[1]  R. Blandford,et al.  Active Galactic Nuclei: The TeV Challenge , 2015, 1511.07515.

[2]  J. Hodgson,et al.  PKS 1502+106: A high-redshift Fermi blazar at extreme angular resolution. Structural dynamics with VLBI imaging up to 86 GHz , 2015, 1511.01085.

[3]  H Germany,et al.  Connection between inner jet kinematics and broadband flux variability in the BL Lac object S5 0716+714 , 2015, 1503.04218.

[4]  L. Sironi,et al.  Relativistic Magnetic Reconnection in Pair Plasmas and Its Astrophysical Applications , 2014, 1412.2451.

[5]  H Germany,et al.  Jet outflow and gamma-ray emission correlations in S5 0716+714 , 2014, 1410.0196.

[6]  M. Cohen,et al.  STUDIES OF THE JET IN BL LACERTAE. II. SUPERLUMINAL ALFVÉN WAVES , 2014, 1409.3599.

[7]  M. Cohen,et al.  STUDIES OF THE JET IN BL LACERTAE. I. RECOLLIMATION SHOCK AND MOVING EMISSION FEATURES , 2014, 1404.0976.

[8]  D. Grupe,et al.  Swift detects BL Lacertae in an historic high state in X-rays , 2012 .

[9]  M. Gurwell,et al.  Gamma-Ray Blazar BL Lacertae at historic high brightness in millimeter, X-ray and far-infrared bands , 2012 .

[10]  T. Krichbaum,et al.  Gamma-ray blazar BL Lacertae: the highest recorded cm/mm radio flux over the past 30 years , 2012 .

[11]  S. Cutini.  Fermi-LAT detection of increasing of gamma-ray activity of BL Lacertae , 2012 .

[12]  W. Alef,et al.  On the calibration of full-polarization 86 GHz global VLBI observations , 2012, 1203.1424.

[13]  Harvard,et al.  Efficient Generation of Jets from Magnetically Arrested Accretion on a Rapidly Spinning Black Hole , 2011, 1108.0412.

[14]  Paul S. Smith,et al.  The inner jet of an active galactic nucleus as revealed by a radio-to-γ-ray outburst , 2008, Nature.

[15]  Paul S. Smith,et al.  Polarimetric Observations of 15 Active Galactic Nuclei at High Frequencies: Jet Kinematics from Bimonthly Monitoring with the Very Long Baseline Array , 2005, astro-ph/0502501.

[16]  G. Denn,et al.  IS THE RADIO CORE OF BL LACERTAE PRECESSING , 2004, astro-ph/0412496.

[17]  Walter Kieran Gear,et al.  Models for high-frequency radio outbursts in extragalactic sources, with application to the early 1983 millimeter-to-infrared flare of 3C 273. , 1985 .