# A PERTURBATIVE ANALYSIS OF SYNCHROTRON SPECTRAL INDEX VARIATION OVER THE MICROWAVE SKY

@article{Saha2015APA, title={A PERTURBATIVE ANALYSIS OF SYNCHROTRON SPECTRAL INDEX VARIATION OVER THE MICROWAVE SKY}, author={Rajib Saha and Pavan K. Aluri}, journal={The Astrophysical Journal}, year={2015}, volume={829} }

In this paper, we implement a perturbative approach, first proposed by Bouchet & Gispert, to estimate the variation of the spectral index of galactic polarized synchrotron emission, using a linear combination of simulated Stokes Q polarization maps of selected frequency bands from WMAP and Planck observations on a region of sky dominated by the synchrotron Stokes Q signal. We find that a first order perturbative analysis recovers the input spectral index map well. Along with the spectral index…

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