Patent ID: 8311742

Claim:
A computer-implemented method for estimating solar plasma velocities, comprising: receiving, at a computer programmed with appropriate software, data representing a plurality of vector magnetograms, each vector magnetogram being a digital image comprising a plurality of pixels p,q and each pixel p,q having corresponding magnetic field components B x and B y in a horizontal image plane and B z in a vertical plane normal to the horizontal image plane, the pixels of each vector magnetogram being co-aligned so that pixel p,q of a first magnetogram corresponds to pixel p,q of a second magnetogram; receiving, at the computer, data representing a plurality of horizontal spatial derivatives ∂ x B x , ∂ x B y , ∂ x B z , ∂ y B x , ∂ y B y , and ∂ y B z of the horizontal and vertical magnetic field components at pixel p,q and further receiving, at the computer, data representing a time derivative ∂ t B z of the vertical magnetic field component at pixel p,q; transforming, at the computer, the data of the spatial and temporal derivatives and the data of the magnetic field components into a structure tensor S, the structure tensor including a plurality of elements expressly containing at least one of the horizontal magnetic field components B x and B y , the terms of the structure tensor being defined to minimize an error between a magnetic induction equation including a modeled plasma velocity and the data of the vector magnetogram; convolving, at the computer, the structure tensor S with a window function centered at pixel p,q to produce a convolved structure tensor S , the elements of the convolved structure tensor S including an average of the values of the structure tensor S over a window defined by the window function; and obtaining, at the computer, a least-squares solution to an error metric C SSD from the convolved structure tensor S , the solution including data of a horizontal plasma velocity v h and a vertical plasma velocity v z at pixel p,q.