### Abstract

Ring-diagram analysis is a technique of local helioseismology used to infer plasma flows in the solar convection zone which generates intermediate data products known as ring-fitting parameters. Knowing the sensitivity of ring-fitting parameters to actual flows in the Sun is important for interpreting these measurements. Working in plane-parallel geometry, we compute the linear sensitivity of ring-fitting parameters to small changes in the local power spectrum and then compute the sensitivity of the power spectrum to time-independent weak local flows. We combine these two results to obtain the three-dimensional Frechet kernels that give the linear sensitivity of ring-fitting parameters to both vertical and horizontal local mass flows. We find that ring measurements are essentially only sensitive to flows that are within the spatial region for which the ring diagram is computed. In addition, we find that the depth dependence of the sensitivity is essentially given by the mode kinetic energy density, as has traditionally been assumed. We show that the exact form of the sensitivity of ring measurements depends on the details of the fitting procedure.

Original language | English (US) |
---|---|

Pages (from-to) | 730-737 |

Number of pages | 8 |

Journal | Astrophysical Journal |

Volume | 662 |

Issue number | 1 I |

DOIs | |

State | Published - Jun 10 2007 |

### Fingerprint

### Keywords

- Scattering
- Sun: helioseismology
- Sun: oscillations
- Sun: rotation
- Waves

### ASJC Scopus subject areas

- Astronomy and Astrophysics
- Space and Planetary Science

### Cite this

*Astrophysical Journal*,

*662*(1 I), 730-737. https://doi.org/10.1086/513683

**The linear sensitivity of helioseismic ring diagrams to local flows.** / Birch, A. C.; Gizon, Laurent; Hindman, B. W.; Haber, D. A.

Research output: Contribution to journal › Article

*Astrophysical Journal*, vol. 662, no. 1 I, pp. 730-737. https://doi.org/10.1086/513683

}

TY - JOUR

T1 - The linear sensitivity of helioseismic ring diagrams to local flows

AU - Birch, A. C.

AU - Gizon, Laurent

AU - Hindman, B. W.

AU - Haber, D. A.

PY - 2007/6/10

Y1 - 2007/6/10

N2 - Ring-diagram analysis is a technique of local helioseismology used to infer plasma flows in the solar convection zone which generates intermediate data products known as ring-fitting parameters. Knowing the sensitivity of ring-fitting parameters to actual flows in the Sun is important for interpreting these measurements. Working in plane-parallel geometry, we compute the linear sensitivity of ring-fitting parameters to small changes in the local power spectrum and then compute the sensitivity of the power spectrum to time-independent weak local flows. We combine these two results to obtain the three-dimensional Frechet kernels that give the linear sensitivity of ring-fitting parameters to both vertical and horizontal local mass flows. We find that ring measurements are essentially only sensitive to flows that are within the spatial region for which the ring diagram is computed. In addition, we find that the depth dependence of the sensitivity is essentially given by the mode kinetic energy density, as has traditionally been assumed. We show that the exact form of the sensitivity of ring measurements depends on the details of the fitting procedure.

AB - Ring-diagram analysis is a technique of local helioseismology used to infer plasma flows in the solar convection zone which generates intermediate data products known as ring-fitting parameters. Knowing the sensitivity of ring-fitting parameters to actual flows in the Sun is important for interpreting these measurements. Working in plane-parallel geometry, we compute the linear sensitivity of ring-fitting parameters to small changes in the local power spectrum and then compute the sensitivity of the power spectrum to time-independent weak local flows. We combine these two results to obtain the three-dimensional Frechet kernels that give the linear sensitivity of ring-fitting parameters to both vertical and horizontal local mass flows. We find that ring measurements are essentially only sensitive to flows that are within the spatial region for which the ring diagram is computed. In addition, we find that the depth dependence of the sensitivity is essentially given by the mode kinetic energy density, as has traditionally been assumed. We show that the exact form of the sensitivity of ring measurements depends on the details of the fitting procedure.

KW - Scattering

KW - Sun: helioseismology

KW - Sun: oscillations

KW - Sun: rotation

KW - Waves

UR - http://www.scopus.com/inward/record.url?scp=34347267267&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34347267267&partnerID=8YFLogxK

U2 - 10.1086/513683

DO - 10.1086/513683

M3 - Article

AN - SCOPUS:34347267267

VL - 662

SP - 730

EP - 737

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 1 I

ER -