Measuring helioseismic travel times

M. Roth, Laurent Gizon, J. G. Beck

    Research output: Contribution to journalArticle

    Abstract

    In time-distance helioseismology wave travel times are measured from the cross-correlation between Doppler velocities recorded at any two locations on the solar surface. We compare two different methods to extract the travel times from the noisy cross-correlation functions. The first method consists of fitting a 5-parameter analytic function to the cross-correlation to obtain the phase travel time. The second method consists of linearizing the distance between the observed cross-correlation and a sliding reference cross-correlation (the only parameter is the travel time). We find that the one-parameter fits are more robust with respect to noise. Using SOHO data from the MDI Structure Program for the years 1996-2003, we study in detail the statistical properties of the noise associated with the travel-time measurements for the two different fitting methods.

    Original languageEnglish (US)
    Pages (from-to)215-222
    Number of pages8
    JournalAstronomische Nachrichten
    Volume328
    Issue number3-4
    DOIs
    StatePublished - Mar 1 2007

    Fingerprint

    cross correlation
    travel time
    travel
    helioseismology
    analytic functions
    sliding
    time measurement
    measuring
    method
    parameter

    Keywords

    • Methods: data analysis
    • Sun: helioseismology

    ASJC Scopus subject areas

    • Astronomy and Astrophysics
    • Space and Planetary Science

    Cite this

    Roth, M., Gizon, L., & Beck, J. G. (2007). Measuring helioseismic travel times. Astronomische Nachrichten, 328(3-4), 215-222. https://doi.org/10.1002/asna.200610722

    Measuring helioseismic travel times. / Roth, M.; Gizon, Laurent; Beck, J. G.

    In: Astronomische Nachrichten, Vol. 328, No. 3-4, 01.03.2007, p. 215-222.

    Research output: Contribution to journalArticle

    Roth, M, Gizon, L & Beck, JG 2007, 'Measuring helioseismic travel times', Astronomische Nachrichten, vol. 328, no. 3-4, pp. 215-222. https://doi.org/10.1002/asna.200610722
    Roth, M. ; Gizon, Laurent ; Beck, J. G. / Measuring helioseismic travel times. In: Astronomische Nachrichten. 2007 ; Vol. 328, No. 3-4. pp. 215-222.
    @article{6eb96581d8a8433aadc8644166b049b4,
    title = "Measuring helioseismic travel times",
    abstract = "In time-distance helioseismology wave travel times are measured from the cross-correlation between Doppler velocities recorded at any two locations on the solar surface. We compare two different methods to extract the travel times from the noisy cross-correlation functions. The first method consists of fitting a 5-parameter analytic function to the cross-correlation to obtain the phase travel time. The second method consists of linearizing the distance between the observed cross-correlation and a sliding reference cross-correlation (the only parameter is the travel time). We find that the one-parameter fits are more robust with respect to noise. Using SOHO data from the MDI Structure Program for the years 1996-2003, we study in detail the statistical properties of the noise associated with the travel-time measurements for the two different fitting methods.",
    keywords = "Methods: data analysis, Sun: helioseismology",
    author = "M. Roth and Laurent Gizon and Beck, {J. G.}",
    year = "2007",
    month = "3",
    day = "1",
    doi = "10.1002/asna.200610722",
    language = "English (US)",
    volume = "328",
    pages = "215--222",
    journal = "Astronomische Nachrichten",
    issn = "0004-6337",
    publisher = "Wiley-VCH Verlag",
    number = "3-4",

    }

    TY - JOUR

    T1 - Measuring helioseismic travel times

    AU - Roth, M.

    AU - Gizon, Laurent

    AU - Beck, J. G.

    PY - 2007/3/1

    Y1 - 2007/3/1

    N2 - In time-distance helioseismology wave travel times are measured from the cross-correlation between Doppler velocities recorded at any two locations on the solar surface. We compare two different methods to extract the travel times from the noisy cross-correlation functions. The first method consists of fitting a 5-parameter analytic function to the cross-correlation to obtain the phase travel time. The second method consists of linearizing the distance between the observed cross-correlation and a sliding reference cross-correlation (the only parameter is the travel time). We find that the one-parameter fits are more robust with respect to noise. Using SOHO data from the MDI Structure Program for the years 1996-2003, we study in detail the statistical properties of the noise associated with the travel-time measurements for the two different fitting methods.

    AB - In time-distance helioseismology wave travel times are measured from the cross-correlation between Doppler velocities recorded at any two locations on the solar surface. We compare two different methods to extract the travel times from the noisy cross-correlation functions. The first method consists of fitting a 5-parameter analytic function to the cross-correlation to obtain the phase travel time. The second method consists of linearizing the distance between the observed cross-correlation and a sliding reference cross-correlation (the only parameter is the travel time). We find that the one-parameter fits are more robust with respect to noise. Using SOHO data from the MDI Structure Program for the years 1996-2003, we study in detail the statistical properties of the noise associated with the travel-time measurements for the two different fitting methods.

    KW - Methods: data analysis

    KW - Sun: helioseismology

    UR - http://www.scopus.com/inward/record.url?scp=34147158291&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=34147158291&partnerID=8YFLogxK

    U2 - 10.1002/asna.200610722

    DO - 10.1002/asna.200610722

    M3 - Article

    VL - 328

    SP - 215

    EP - 222

    JO - Astronomische Nachrichten

    JF - Astronomische Nachrichten

    SN - 0004-6337

    IS - 3-4

    ER -