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Using MHD seismology by observed kink waves, the magnetic field profile of acoronal streamer has been investigated. STEREO-B/EUVI temporal image data on 7March 2012 shows an evolution of two consecutive EUV waves that interact withthe footpoint of a coronal streamer evident in the co-spatial and co-temporalSTEREO-B/COR-I observations. The evolution of EUV waves is clearly evident inSTEREO-B/EUVI, and its energy exchange with coronal streamer generates kinkoscillations. We estimate the phase velocities of the kink wave perturbationsby tracking it at different heights of the coronal streamer. We also estimatethe electron densities inside and outside the streamer using SSI of polarizedbrightness images in STEREO-B/COR-1 observations. Taking into account the MHDtheory of kink waves in a cylindrical waveguide, their observed properties atvarious heights, and density contrast of the streamer, we estimate the radialprofile of magnetic field within this magnetic structure. Both the kink wavesdiagnose the exponentially decaying radial profiles of the magnetic field incoronal steamer upto 3 solar radii. Within the limit of uncertainties in themeasurements, it is indicated that coronal magnetic field of the streamervaries slowly in time at various heights, although its nature always remainsexponentially decaying. It is seen that during the evolution of second kinkmotion in the streamer, it increases in brightness, and also in areal extentslightly, which may be associated with the decreased photospheric magnetic fluxat its footpoint. As a result, the magnetic field profile produced by thesecond kink wave is reduced within the streamer compared to the one diagnosedby the first one. The precisely estimated magnetic field profiles with theuncertainty less than 10% match well with the empirical profile and variousobservational estimations of the outer coronal magnetic field.

Inference of Magnetic Field in the Coronal Streamer Invoking Kink Wave Motions generated by Multiple EUV Waves