**
A recent, major, puzzle in the core-level photo emission spectra of
doped manganites is the observation of a 1-2 eV wide shoulder with
intensity varying with temperature T as the square of the
magnetization over a T scale of order 200K, an order of magnitude
less than electronic energies. In this talk I discuss a recent
theory we have developed* to address and resolve this puzzle, by
extending the recently proposed (localized-polaron +
mobile-electron) two fluid model for manganites to include core-hole
effects. The shoulder seems to arise from a broadened X-ray edge
singularity whose exponent varies with temperature, reflecting the
rapid redistribution of the spectral density of the mobile electrons
due to their strong scattering from thermally disordered t _{2g}
core spins. Furthermore, our theory leads to a correspondence
between spectral changes due to increasing doping and decreasing
temperature, as experimentally observed.
(* work done in collaboration with Prabuddha Sanyal, Subhra Sen
Gupta, Nandan Pakhira, D. D. Sarma and T. V. Ramakrishnan
( http://arxiv.org/abs/0704.3923), and to be published)
**

**
**