Inflation with a running spectral index in supergravity

The first year Wilkinson Microwave Anisotropy Probe data favor primordial adiabatic fluctuation with a running spectral index with n(s) > 1 on a large scale and n(2) < 1 on a smaller scale. The model building of inflation that predicts perturbations with such a spectrum is a challenge, because most models predict fluctuations with either n(2) > 1 (hybrid inflation) or n(2) < 1 (new, chaotic, or topological inflation). We give a sensible particle physics model in supergravity that accommodates the desired running of the spectral index using double inflation.