Probing the precise location of the radio core in the TeV blazar Mrk 501 with VERA at 43 GHz

Shoko Koyama, Motoki Kino, Akihiro Doi, Kotaro Niinuma, Kazuhiro Hada, Hiroshi Nagai, Mareki Honma, Kazunori Akiyama, Marcello Giroletti, Gabriele Giovannini, Monica Orienti, Naoki Isobe, Jun Kataoka, David Paneque, Hideyuki Kobayashi, Keiichi Asada

    Research output: Contribution to journalArticle

    2 Citations (Scopus)

    Abstract

    We investigate the position of the radio core in a blazar by multi-epoch astrometric observations at 43 GHz. Using the VLBI Exploration of Radio Astrometry (VERA), we have conducted four adjacent observations in 2011 February and another four in 2011 October, and succeeded in measuring the position of the radio core in the TeV blazar Mrk 501 relative to a distant compact quasar NRAO 512. During our observations, we find that (1) there is no positional change within ∼0.2 mas or ∼2.0 pc de-projected with ±1 σ error for the weighted-mean phase-referenced positions of the Mrk 501 core relative to NRAO 512 over four adjacent days, and (2) there is an indication of position change for the 3C 345 core relative to NRAO 512. By applying our results to the standard internal shock model for blazars, we constrain the bulk Lorenz factors of the ejecta.

    Original languageEnglish
    Article number67
    JournalPublications of the Astronomical Society of Japan
    Volume67
    Issue number4
    DOIs
    Publication statusPublished - 2015 May 25

    Fingerprint

    very long base interferometry
    astrometry
    very long baseline interferometry
    radio
    ejecta
    blazars
    quasars
    indication
    shock
    time measurement

    Keywords

    • Astrometry
    • Galaxies: active
    • Galaxies: individual (Mrk 501 3C 345, NRAO 512)
    • Radio continuum: galaxies
    • Techniques: interferometric

    ASJC Scopus subject areas

    • Astronomy and Astrophysics
    • Space and Planetary Science

    Cite this

    Probing the precise location of the radio core in the TeV blazar Mrk 501 with VERA at 43 GHz. / Koyama, Shoko; Kino, Motoki; Doi, Akihiro; Niinuma, Kotaro; Hada, Kazuhiro; Nagai, Hiroshi; Honma, Mareki; Akiyama, Kazunori; Giroletti, Marcello; Giovannini, Gabriele; Orienti, Monica; Isobe, Naoki; Kataoka, Jun; Paneque, David; Kobayashi, Hideyuki; Asada, Keiichi.

    In: Publications of the Astronomical Society of Japan, Vol. 67, No. 4, 67, 25.05.2015.

    Research output: Contribution to journalArticle

    Koyama, S, Kino, M, Doi, A, Niinuma, K, Hada, K, Nagai, H, Honma, M, Akiyama, K, Giroletti, M, Giovannini, G, Orienti, M, Isobe, N, Kataoka, J, Paneque, D, Kobayashi, H & Asada, K 2015, 'Probing the precise location of the radio core in the TeV blazar Mrk 501 with VERA at 43 GHz', Publications of the Astronomical Society of Japan, vol. 67, no. 4, 67. https://doi.org/10.1093/pasj/psu144
    Koyama, Shoko ; Kino, Motoki ; Doi, Akihiro ; Niinuma, Kotaro ; Hada, Kazuhiro ; Nagai, Hiroshi ; Honma, Mareki ; Akiyama, Kazunori ; Giroletti, Marcello ; Giovannini, Gabriele ; Orienti, Monica ; Isobe, Naoki ; Kataoka, Jun ; Paneque, David ; Kobayashi, Hideyuki ; Asada, Keiichi. / Probing the precise location of the radio core in the TeV blazar Mrk 501 with VERA at 43 GHz. In: Publications of the Astronomical Society of Japan. 2015 ; Vol. 67, No. 4.
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    AU - Kino, Motoki

    AU - Doi, Akihiro

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    AU - Hada, Kazuhiro

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    AU - Honma, Mareki

    AU - Akiyama, Kazunori

    AU - Giroletti, Marcello

    AU - Giovannini, Gabriele

    AU - Orienti, Monica

    AU - Isobe, Naoki

    AU - Kataoka, Jun

    AU - Paneque, David

    AU - Kobayashi, Hideyuki

    AU - Asada, Keiichi

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    KW - Techniques: interferometric

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