English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We present 23 new VLBA images of the six established TeV blazars Markarian421, Markarian 501, H 1426+428, 1ES 1959+650, PKS 2155-304, and 1ES 2344+514,obtained from 2005 to 2009. Most images were obtained at 43 GHz, and theyreveal the parsec-scale structures of three of these sources (1ES 1959+650, PKS2155-304, and 1ES 2344+514) at factors of two to three higher resolution thanhas previously been attained. Most of the remaining images map the linearpolarization structures at a lower frequency of 22 GHz. We discuss thetransverse structures of the jets as revealed by the high-frequency andpolarimetric imaging. The transverse structures include significantlimb-brightening in Mrk 421, and spine-sheath structures in the electric vectorposition angle (EVPA) and fractional polarization distributions in Mrk 421, Mrk501, and 1ES 1959+650. We use new measured component positions to updatemeasured apparent jet speeds, in many cases significantly reducing thestatistical error over previously published results. With the increasedresolution at 43 GHz, we detect new components within 0.1-0.2 mas of the corein most of these sources. No motion is apparent in these new components overthe time span of our observations, and we place upper limits on the apparentspeeds of the components near the core of less than 2c. From those limits, weconclude that Gamma2 < Gamma1^{1/2} at about 10^5 Schwarzschild radii, whereGamma1 and Gamma2 are the bulk Lorentz factors in the TeV-emitting and 43GHz-emitting regions, respectively, assuming that their velocity vectors arealigned.

The Jets of TeV Blazars at Higher Resolution: 43 GHz and Polarimetric VLBA Observations from 2005-2009