An optical polarization survey for BL Lacs

We re-examine the differences observed in the pc-scale magnetic field geometry of high and low optical polarization quasars (HPQs, LPRQs) using the MOJAVE sample. We find that, as previously reported, HPQ jets exhibit predominantly transverse B fields while LPRQ jets tend to display longitudinal B fields. We attempt to understand these results along with the different B field geometry observed in the low and high energy peaked BL Lacs (LBLs, HBLs) using a simple picture wherein the spinning central black holes in these AGNs influence the speed and strength of the jet components (spine, sheath). Higher spin rates in HPQs compared to LPRQs and in LBLs compared to HBLs could explain the different total radio powers, VLBI jet speeds, and the observed B field geometry in these AGN classes.

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Magnetic-field strengths from optical polarization data

Symposium - International Astronomical Union ◽

10.1017/s0074180900101263 ◽

1967 ◽

Vol 31 ◽

pp. 381-383

Author(s):

J. M. Greenberg

Keyword(s):

Magnetic Field ◽

Optical Polarization ◽

Polarization Data ◽

Term Model ◽

Source Of Information ◽

Field Strengths

Van de Hulst (Paper 64, Table 1) has marked optical polarization as a questionable or marginal source of information concerning magnetic field strengths. Rather than arguing about this–I should rate this method asq+-, or quarrelling about the term ‘model-sensitive results’, I wish to stress the historical point that as recently as two years ago there were still some who questioned that optical polarization was definitely due to magnetically-oriented interstellar particles.

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Quasi-Optical Polarization Attenuators in the Terahertz Frequency Band

Telecommunications and Radio Engineering ◽

10.1615/telecomradeng.v67.i13.80 ◽

2008 ◽

Vol 67 (13) ◽

pp. 1207-1215 ◽

Cited By ~ 1

Author(s):

V. K. Kiselyov ◽

M. S. Yanovsky ◽

V. I. Bezborodov ◽

Ye. M. Kuleshov

Keyword(s):

Frequency Band ◽

Optical Polarization ◽

Terahertz Frequency

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Contrast Enhancement of Mammograms by Optical Polarization of the Viewing Environment.

10.21236/ada328921 ◽

1997 ◽

Author(s):

David C. Spelic

Keyword(s):

Contrast Enhancement ◽

Optical Polarization

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Strong and robust polarization anisotropy of site- and size-controlled single InGaN/GaN quantum wires

Scientific Reports ◽

10.1038/s41598-020-71590-x ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Hwan-Seop Yeo ◽

Kwanjae Lee ◽

Young Chul Sim ◽

Seoung-Hwan Park ◽

Yong-Hoon Cho

Keyword(s):

Quantum Wire ◽

Quantum Wires ◽

Geometrical Shape ◽

Optical Polarization ◽

Polarization Anisotropy ◽

Single Quantum ◽

Group Iii ◽

Highly Efficient ◽

Group Iii Nitride ◽

Size Controlled

Abstract Optical polarization is an indispensable component in photonic applications, the orthogonality of which extends the degree of freedom of information, and strongly polarized and highly efficient small-size emitters are essential for compact polarization-based devices. We propose a group III-nitride quantum wire for a highly-efficient, strongly-polarized emitter, the polarization anisotropy of which stems solely from its one-dimensionality. We fabricated a site-selective and size-controlled single quantum wire using the geometrical shape of a three-dimensional structure under a self-limited growth mechanism. We present a strong and robust optical polarization anisotropy at room temperature emerging from a group III-nitride single quantum wire. Based on polarization-resolved spectroscopy and strain-included 6-band k·p calculations, the strong anisotropy is mainly attributed to the anisotropic strain distribution caused by the one-dimensionality, and its robustness to temperature is associated with an asymmetric quantum confinement effect.

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Ultrafast electrical control of optical polarization in hybrid semiconductor structure

Physica E Low-dimensional Systems and Nanostructures ◽

10.1016/j.physe.2021.114755 ◽

2021 ◽

pp. 114755

Author(s):

I.V. Rozhansky ◽

V.N. Mantsevich ◽

N.S. Maslova ◽

P.I. Arseyev ◽

N.S. Averkiev ◽

...

Keyword(s):

Semiconductor Structure ◽

Optical Polarization ◽

Electrical Control

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The Environment of OJ 287: Nearby Galaxies and a Long Optical Jet?

Symposium - International Astronomical Union ◽

10.1017/s0074180900079961 ◽

1996 ◽

Vol 175 ◽

pp. 47-48

Author(s):

A. Sillanpää ◽

L. Takalo ◽

K. Nilsson ◽

T. Pursimo ◽

P. Teerikorpi ◽

...

Keyword(s):

Large Scale ◽

Radio Galaxies ◽

Trigger Mechanism ◽

Galaxy Clustering ◽

Bl Lac Objects ◽

Close Interaction ◽

Relativistic Jet ◽

Bl Lac ◽

Nearby Galaxies ◽

Bl Lacs

A widely accepted model for BL Lac objects is that they are radio galaxies with a relativistic jet pointing almost directly towards us. But we need a clear trigger mechanism for these jets. One possibility is the close interaction between the BL Lac host and the closeby galaxies (e.g. Heckman et al. 1986). This interaction has been seen many times in the case of quasars (Hutchings et al. 1989) but not so much is known about the close surroundings of the BL Lac objects although there has been some pioneer work like Stickel et al. (1993). The problem has usually been that the images are not deep enough and that the seeing has not been so good. To clarify the situation we have started an observing program to get very deep images in the sub-arcsecond seeing conditions from the whole 1 Jy sample (Stickel et al. 1991) of BL Lac objects. The aims of this study are: 1. to search for very close companions to the BL Lacs, 2. to study the large scale galaxy clustering around the BL Lacs and 3. to study the BL Lac hosts themselves.

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