On the Time Variable Rotation Measure in the Core Region of Markarian 421
In this conference contribution, we discuss and interpret the time variable rotation measure (RM) detected in the core region of the TeV blazar Markarian 421 (Mrk 421). We monitored Mrk 421 during 2011 with one observing run per month at 15, 24, and 43 GHz with the American Very Long Baseline Array....
Main Authors: | , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
MDPI AG
2017-09-01
|
Series: | Galaxies |
Subjects: | |
Online Access: | https://www.mdpi.com/2075-4434/5/4/57 |
id |
doaj-0799c8ec6fb945289bd3975b7d7d036f |
---|---|
record_format |
Article |
spelling |
doaj-0799c8ec6fb945289bd3975b7d7d036f2020-11-24T21:25:09ZengMDPI AGGalaxies2075-44342017-09-01545710.3390/galaxies5040057galaxies5040057On the Time Variable Rotation Measure in the Core Region of Markarian 421Rocco Lico0José L. Gómez1Keiichi Asada2Antonio Fuentes3Dipartimento di Fisica e Astronomia, Università di Bologna, via Gobetti 93/3, 40129 Bologna, ItalyInstituto de Astrofísica de Andalucía, IAA-CSIC, Apdo. 3004, 18080 Granada, SpainInstitute of Astronomy and Astrophysics, Academia Sinica, PO Box 23-141, Taipei 10617, TaiwanInstituto de Astrofísica de Andalucía, IAA-CSIC, Apdo. 3004, 18080 Granada, SpainIn this conference contribution, we discuss and interpret the time variable rotation measure (RM) detected in the core region of the TeV blazar Markarian 421 (Mrk 421). We monitored Mrk 421 during 2011 with one observing run per month at 15, 24, and 43 GHz with the American Very Long Baseline Array. We explore the possible connection between the RM and the accretion rate, and we investigate the Faraday screen properties and its location with respect to the jet emitting region. Among the various scenarios, the jet sheath is the most promising candidate for being the main source of Faraday rotation. We interpret the RM sign reversals observed during the one-year monitoring within the context of the magnetic tower models by invoking the presence of two nested helical magnetic fields in the relativistic jet with opposite helicities, originating through the Poynting–Robertson cosmic battery effect. The net observed RM values result from the relative contribution of both inner and outer helical fields.https://www.mdpi.com/2075-4434/5/4/57active galaxies: magnetic fieldsgalaxies: jetsBL Lacertae objects: individual: Mrk 421 |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Rocco Lico José L. Gómez Keiichi Asada Antonio Fuentes |
spellingShingle |
Rocco Lico José L. Gómez Keiichi Asada Antonio Fuentes On the Time Variable Rotation Measure in the Core Region of Markarian 421 Galaxies active galaxies: magnetic fields galaxies: jets BL Lacertae objects: individual: Mrk 421 |
author_facet |
Rocco Lico José L. Gómez Keiichi Asada Antonio Fuentes |
author_sort |
Rocco Lico |
title |
On the Time Variable Rotation Measure in the Core Region of Markarian 421 |
title_short |
On the Time Variable Rotation Measure in the Core Region of Markarian 421 |
title_full |
On the Time Variable Rotation Measure in the Core Region of Markarian 421 |
title_fullStr |
On the Time Variable Rotation Measure in the Core Region of Markarian 421 |
title_full_unstemmed |
On the Time Variable Rotation Measure in the Core Region of Markarian 421 |
title_sort |
on the time variable rotation measure in the core region of markarian 421 |
publisher |
MDPI AG |
series |
Galaxies |
issn |
2075-4434 |
publishDate |
2017-09-01 |
description |
In this conference contribution, we discuss and interpret the time variable rotation measure (RM) detected in the core region of the TeV blazar Markarian 421 (Mrk 421). We monitored Mrk 421 during 2011 with one observing run per month at 15, 24, and 43 GHz with the American Very Long Baseline Array. We explore the possible connection between the RM and the accretion rate, and we investigate the Faraday screen properties and its location with respect to the jet emitting region. Among the various scenarios, the jet sheath is the most promising candidate for being the main source of Faraday rotation. We interpret the RM sign reversals observed during the one-year monitoring within the context of the magnetic tower models by invoking the presence of two nested helical magnetic fields in the relativistic jet with opposite helicities, originating through the Poynting–Robertson cosmic battery effect. The net observed RM values result from the relative contribution of both inner and outer helical fields. |
topic |
active galaxies: magnetic fields galaxies: jets BL Lacertae objects: individual: Mrk 421 |
url |
https://www.mdpi.com/2075-4434/5/4/57 |
work_keys_str_mv |
AT roccolico onthetimevariablerotationmeasureinthecoreregionofmarkarian421 AT joselgomez onthetimevariablerotationmeasureinthecoreregionofmarkarian421 AT keiichiasada onthetimevariablerotationmeasureinthecoreregionofmarkarian421 AT antoniofuentes onthetimevariablerotationmeasureinthecoreregionofmarkarian421 |
_version_ |
1725984562364809216 |