Context : Scattering polarization in the Sr I 4607.3 Å line observed with high resolution is an important diagnostic of the Sun ’ s atmosphere and magnetism at small spatial scales .
Investigating the scattering polarization altered by the Hanle effect is key to constraining the role of small-scale magnetic activity in solar atmospheric activity and energy balance .
At present , spatially resolved observations of this diagnostic are rare and have not been reported as close to the disk center as for \mu = 0.6 .

Aims : Our aim is to measure the scattering polarization in the Sr I line at \mu = 0.6 and to identify the spatial fluctuations with a statistical approach .

Methods : Using the Fast Solar Polarimeter ( FSP ) mounted on the TESOS filtergraph at the German Vacuum Tower Telescope ( VTT ) in Tenerife , Spain , we measured both the spatially resolved full Stokes parameters of the Sr I line at \mu = 0.6 and the center-to-limb variation of the spatially averaged Stokes parameters .

Results : We find that the center-to-limb variation of the scattering polarization in the Sr I line measured with FSP is consistent with previous measurements .
A statistical analysis of Stokes Q / I ( i.e. , the linear polarization component parallel to the solar limb ) , sampled with 0.16″ pixel ^ { -1 } in the line core of Sr I reveals that the signal strength is inversely correlated with the intensity in the continuum .
We find stronger linear polarimetric signals corresponding to dark areas ( intergranular lanes ) in the Stokes I continuum image .
In contrast , independent measurements at \mu = 0.3 show a positive correlation of Q / I with respect to the continuum intensity .
We estimate that the patch diameter responsible for the excess Q / I signal is on the order of 0.5″-1″ .

Conclusions : The presented observations and the statistical analysis of Q / I signals at \mu = 0.6 complement reported scattering polarization observations as well as simulations .
The FSP has proven to be a suitable instrument to measure spatially resolved scattering polarization signals .
In the future , a systematic center-to-limb series of observations with subgranular spatial resolution and increased polarimetric sensitivity ( ¡ 10 ^ { -3 } ) compared to that in the present study is needed in order to investigate the change in trend with \mu that the comparison of our results with the literature suggests .