Aaron C Birch
Colorado Research Associates
a division of NorthWest Research Associates, Inc.
3380 Mitchell Lane
Boulder CO 80301-5410 USA

phone: 303 415 9701 x236
fax: 303 415 9702

email: aaronb at cora.nwra.com

Links


NASA LWS TR&T Project to Predict the Emergence of Active Regionsmy dissertation
Matlab codes for computing kernels
Matlab codes for computing rays

Papers

Jackiewicz, J., Gizon, L., Birch, A. C., and Duvall, T. L., Jr.
Time-Distance Helioseismology: Sensitivity of f-mode Travel Times to Flows
ApJ, 671, 1051 (2007)

Braun, D. C., Birch, A. C., Benson, D., Stein, R. F., Nordlund, A.
Helioseismic Holography of Simulated Solar Convection and Prospects for the Detection of Small-Scale Subsurface Flows
ApJ, 669, 1395 (2007)

Birch, A. C., Gizon, L., Hindman, B.~W., Haber, D. A.
The Linear Sensitivity of Helioseismic Ring Diagrams to Local Flows
ApJ, 662, 730 (2007)

Jackiewicz, J., Gizon, L., Birch, A. C., Thompson, M. J.
A procedure for the inversion of f-mode travel times for solar flows
Astron. Nach., 328, 234 (2007)

Birch, A.C. & Gizon, L.
Linear Sensitivity of Helioseismic Travel Times to Local Flows
Astronomische Nachrichten, 328, 228 (2007)

Braun, D.C. & Birch, A.C.
Observed Frequency Variations of Solar P-Mode Travel Times as Evidence for Surface Effects in Sunspot Seismology
ApJ, 647, L187 (2006)

Couvidat, S. & Birch, A.C.
Optimal Gaussian Phase-Speed Filters in Time-Distance Helioseismology
Sol. Phys., 647, 187 (2006)

Duvall, T.L., Jr., Birch, A.C., & Gizon, L. 2006
Direct Measurements of Wave Kernels in Time-Distance Helioseismology
ApJ, 646, 553 (2006)

Rajaguru, S.P., Birch, A.C., Duvall, T.L., Jr, Thompson, M.J., & Zhao, J.
Sensitivity of Time-Distance Helioseismic Measurements to Spatial Variation of Oscillation Amplitudes I. Observations and a Numerical Model
ApJ, 646, 543 (2006)

Gizon, L., Hanasoge, S., Birch, A.C.
Scattering of Acoustic Waves by a Magnetic Cylinder: Accuracy of the Born Approximation
ApJ, 643, 549 (2006)

Couvidat, S., Birch, A.C., & A.G. Kosovichev
3D Inversion of Sound Speed Below a Sunspot in the Born Approximation
ApJ, 640, 516 (2005)

Gizon, L. & Birch, A.C.
Local Helioseismology
Living Reviews in Solar Physics (2005)

Couvidat, S., Gizon, L., Birch, A. C., Larsen, R. M., & Kosovichev, A.G.
Time-Distance Helioseismology: Inversion of Noisy Correlated Data
ApJS, 158, 217 (2005)

Birch, A C
The Current Status of Theory for Time-Distance Helioseismology
GONG2004/SOHO14 proceedings p. 138 (2004)

Birch, A C and Felder, G
The Born Approximation for Time-Distance Helioseismology of Flows
Apj 616 1261 (2004)

Gizon, L & Birch, A. C.
Time-Distance Helioseismology: Noise Estimation
ApJ 614 472 (2004)

Birch, A C, Kosovichev, A G and Duvall T L Jr.
Sensitivity of Acoustic Wave Travel Times to Sound-Speed Perturbations in the Solar Interior
ApJ 608 580 (2004)

Couvidat, S, Birch, A C, Kosovichev, A G, and Zhao, J.
Three-dimensional Inversion of Time-Distance Helioseismology Data: Ray-Path and Fresnel-Zone Approximations
ApJ 607 554 (2004)

Gizon, L & Birch, A. C. (2002)
Time-Distance Helioseismology: The Forward Problem for Random Distributed Sources,
ApJ 571 966 (2002)

Birch, A C, Kosovichev, A G, Price, G H, Schlottman, R B
 The Accuracy of the Born and Ray Approximations in Time-Distance Helioseismology
ApJ, 561, L229 (2001)

Birch, A. C. & Kosovichev A. G., Spiegal, E. A. & Tao, L
Resonant Vibrational Instabilities in Magnetized Stellar Atmospheres Sol. Phys, 199, 291
Sol. Phys, 199, 291 (2001)

Birch, A. C. & Kosovichev, A. G. (2001)
The Born Approximation in Time-Distance Helioseismology
in Proceedings of the SOHO 10/GONG 2000 Workshop: Helio- and asteroseismology at the dawn of the millennium Ed. A. Wilson (Noordwijk: ESA) 187

Birch, A. C. & Kososichev, A. G.
Travel Time Sensitivity Kernels
Sol. Phys. 192, 193 (200)

Birch, A. C. & Kosovichev, A. G. 
Latitudinal Variation of Solar Subsurface Rotation Inferred from p-Mode Frequency Splittings Measured with SOI-MDI and GONG
ApJ 503 L187 (1998)

Birch, A. C. & Kosovichev, A. G. (1998)
Latitudinal Dependence of the Solar Rotation Rate in the Upper Convection Zone,
in Stucture and Dynamics of the Interior of the Sun and Sun-Like Stars SOHO6/GONG98 ed. S. Korzenneik and A. Wilson (Noordwijk: ESA), 187