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Related papers: Evidence for Toroidal B-Field Structures in BL Lac…

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We have conducted a survey of Faraday rotation in a sample of 191 compact radio-loud AGNs as part of the MOJAVE (Monitoring of Jets in Active galactic nuclei with VLBA Experiments) project. The observations were carried out with the VLBA at…

High Energy Astrophysical Phenomena · Physics 2012-05-03 T. Hovatta , M. L. Lister , M. F. Aller , H. D. Aller , D. C. Homan , Y. Y. Kovalev , A. B. Pushkarev , T. Savolainen

Observational studies of collimation in jets in active galactic nuclei (AGN) are a key to understanding their formation and acceleration processes. We have performed an automated search for jet shape transitions in a sample of 367 AGN using…

We present an analysis of the core linear polarization properties of 387 parsec-scale active galactic nuclei (AGN) jets. Using 15 GHz VLBA data, we revisit the conclusions of the first paper in this series with multi-epoch measurements and…

Astrophysics of Galaxies · Physics 2018-08-16 M. A. Hodge , M. L. Lister , M. F. Aller , H. D. Aller , Y. Y. Kovalev , A. B. Pushkarev , T. Savolainen

The BL Lacertae (BL Lac) object OJ 287 is one of the most dynamic blazars across the directly accessible observational windows: spectral, timing, polarization, and imaging. Apart from behaviors considered characteristics of blazars, it…

High Energy Astrophysical Phenomena · Physics 2022-07-01 Pankaj Kushwaha

Radial gradients of the brightness temperatures along the parsec-scale jets of Active Galactic Nuclei (AGN) can be used to infer the energy balance and to estimate the parameter range of physical conditions in these regions. In this paper,…

High Energy Astrophysical Phenomena · Physics 2025-04-03 E. V. Kravchenko , I. N. Pashchenko , D. C. Homan , Y. Y. Kovalev , M. L. Lister , A. B. Pushkarev , E. Ros , T. Savolainen

The first measurements of the average transverse-momentum fraction ($\langle z \rangle$) as a function of transverse momentum ($p_{\rm T}$) for strange baryons ($\Lambda$ and $\bar{\Lambda}$) and strange mesons ($K_{\rm S}^0$), produced in…

High Energy Physics - Experiment · Physics 2026-03-23 ALICE Collaboration

We used 15 GHz VLBA observations of 366 sources having at least 5 epochs within a time interval 1995-2013 from the MOJAVE program and/or its predecessor, the 2 cm VLBA Survey. For each source we produced a corresponding stacked image…

High Energy Astrophysical Phenomena · Physics 2015-02-03 Alexander B. Pushkarev , Matthew L. Lister , Yuri Y. Kovalev , Tuomas Savolainen

We present a measurement of the shapes of b-jets using 300 pb-1 of data obtained with the upgraded Collider Detector at Fermilab (CDF II) in p pbar collisions at center of mass energy sqrt{s}=1.96 TeV. This measurement covers a wide…

High Energy Physics - Experiment · Physics 2010-05-12 CDF Collaboration , A. Abulencia

We present the measurement of a new set of jet shape observables for track-based jets in central Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}} = 2.76$ TeV. The set of jet shapes includes the first radial moment or angularity, $g$; the…

Nuclear Experiment · Physics 2019-01-21 ALICE Collaboration

Recent multifrequency polarimetric observations of the eponymous blazar BL Lac reveal an extremely large degree of polarization in the optical band (average of $25\%$, reaching $45\%$), together with a small ($\lesssim 7\%$) degree of…

High Energy Astrophysical Phenomena · Physics 2025-07-14 F. Tavecchio , F. Bolis , E. Sobacchi , S. Boula , A. Sciaccaluga

We have observed the BL Lac object Markarian 501 at 1.4 GHz with the High Sensitivity Array and at 86 GHz with the global VLBI mm array. Thanks to the great resolution and sensitivity provided by these instruments, we probe regions of the…

Astrophysics · Physics 2007-08-30 G. Giovannini , M. Giroletti , G. B. Taylor

The possibility to use observations of lensed relativistic jets on very small angular scales to construct proper models of spiral lens galaxies and to independently determine the Hubble constant is considered. On the example of the system…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-14 T. I. Larchenkova , A. A. Lutovinov , N. S. Lyskova

We present simulations of relativistic jets propagating in a nonuniform medium. Specifically, we study the bending of jets propagating obliquely to the vector of the density-gradient. Our results are applied to the NGC 4258, where such a…

Astrophysics · Physics 2008-02-03 T. Plewa , J. Ma. Marti , E. Mueller , M. Rozyczka , M. Sikora

The aim of this work is to explore possible medium modifications to the substructure of inclusive charged jets in Pb-Pb relative to proton-proton collisions by measuring a set of jet shapes. The set of shapes includes the radial moment,…

Nuclear Experiment · Physics 2019-08-13 Leticia Cunqueiro

Very long baseline interferometric observations of the radio galaxy 3C 120 show a systematic presence of gradients in Faraday rotation and degree of polarization across and along the jet. These are revealed by the passage of multiple…

Astrophysics · Physics 2008-07-17 J. L. Gomez , I. Agudo , A. P. Marscher , S. G. Jorstad , M. Roca-Sogorb

Jet substructure in heavy-ion collisions is a rapidly evolving area with lots of intriguing new measurements. This contribution presents a selection of recent jet-substructure measurements from experiments at the LHC, in particular,…

Nuclear Experiment · Physics 2024-10-08 Robert Vertesi

A new continuous classification system for BL Lacertae (BL Lac) objects is proposed. The peak frequency of the synchrotron component in the $\nu L_{\nu}$ spectrum is used as a classifying parameter. The application of the accelerating inner…

Astrophysics · Physics 2007-05-23 Markos Georganopoulos , Alan P. Marscher

Observations made with the VLBA have led to fundamental advances in our understanding of how radio jets in AGN evolve from parsec-scales out to distances exceeding several hundred kiloparsecs. In this review I discuss current models of…

Astrophysics · Physics 2007-07-12 Matthew L. Lister

We describe a geometric model for synchrotron radiation from blazar jets, involving multiple emission zones with turbulent magnetic fields and a transient core with a helical B field. Including the effects of jet divergence, particle…

High Energy Astrophysical Phenomena · Physics 2018-09-19 A. L. Peirson , Roger W. Romani

With the assumption that the optical variability timescale is dominated by the cooling time of the synchrotron process for BL Lac objects, we estimate time dependent magnetic field strength of the emission region for two BL Lac objects. The…

High Energy Astrophysical Phenomena · Physics 2022-01-19 Xu-Liang Fan , Da-Hai Yan , Qing-Wen Wu , Xu Chen