diff --git a/postprocessor.py b/postprocessor.py
index d0f7520..65a1927 100644
--- a/postprocessor.py
+++ b/postprocessor.py
@@ -463,7 +463,7 @@ class PostProcessor(HDF5Container):
         Returns the position in normalized units centered on the position of the star
         """
         pos = dset.get_cell_centers()
-        pos = pos - (np.array(self.pp_params.disk.pos_star) / self.lbox)
+        pos = pos - np.array(self.pp_params.disk.center)
         return pos
 
     def oct_getter_vect_r(self, dset, name_vect):
@@ -891,23 +891,15 @@ class PostProcessor(HDF5Container):
             # Get coordinates
             im_extent = np.array(self.save.root.maps._v_attrs.im_extent) * self.lbox
             map_size = self.pp_params.pymses.map_size
-            pos_star = self.pp_params.disk.pos_star
+            center = self.pp_params.disk.center * self.lbox
 
             # Physical size of cells
             dx = (im_extent[1] - im_extent[0]) / map_size
             dy = (im_extent[3] - im_extent[2]) / map_size
 
             # Physical coordinates of the center of the cells
-            x = (
-                np.linspace(im_extent[0], im_extent[1], map_size)
-                + 0.5 * dx
-                - pos_star[0]
-            )
-            y = (
-                np.linspace(im_extent[2], im_extent[3], map_size)
-                + 0.5 * dy
-                - pos_star[1]
-            )
+            x = np.linspace(im_extent[0], im_extent[1], map_size) + 0.5 * dx - center[0]
+            y = np.linspace(im_extent[2], im_extent[3], map_size) + 0.5 * dy - center[1]
 
             xx, yy = np.meshgrid(x, y)
             rr = np.sqrt(xx ** 2 + yy ** 2)
@@ -926,14 +918,12 @@ class PostProcessor(HDF5Container):
         """
         Computes radial bins (for disk)
         """
-        pos_star = self.pp_params.disk.pos_star
+        center = self.pp_params.disk.center * self.lbox
         im_extent = np.array(self.save.root.maps._v_attrs.im_extent) * self.lbox
 
         # radius of the corner of the box plus a margin
         rad_of_box = (
-            np.sqrt(
-                (im_extent[1] - pos_star[0]) ** 2 + (im_extent[3] - pos_star[1]) ** 2
-            )
+            np.sqrt((im_extent[1] - center[0]) ** 2 + (im_extent[3] - center[1]) ** 2)
             + 0.1
         )
 
@@ -969,7 +959,7 @@ class PostProcessor(HDF5Container):
         """
         im_extent = np.array(self.save.root.maps._v_attrs.im_extent) * self.lbox
         map_size = self.pp_params.pymses.map_size
-        pos_star = self.pp_params.disk.pos_star
+        center = self.pp_params.disk.center * self.lbox
 
         # Physical size of cells
         dx = (im_extent[1] - im_extent[0]) / map_size
@@ -982,7 +972,7 @@ class PostProcessor(HDF5Container):
         xx, yy = np.meshgrid(x, y)
 
         # Physical radius
-        rr = np.sqrt((xx - pos_star[0]) ** 2 + (yy - pos_star[1]) ** 2)
+        rr = np.sqrt((xx - center[0]) ** 2 + (yy - center[1]) ** 2)
         return rr
 
     def _bins_on_map(self, ax_los="z"):
@@ -1306,15 +1296,15 @@ class PostProcessor(HDF5Container):
         # Get coordinates
         im_extent = np.array(self.save.root.maps._v_attrs.im_extent) * self.lbox
         map_size = self.pp_params.pymses.map_size
-        pos_star = self.pp_params.disk.pos_star
+        center = self.pp_params.disk.center * self.lbox
 
         # Physical size of cells
         dx = (im_extent[1] - im_extent[0]) / map_size
         dy = (im_extent[3] - im_extent[2]) / map_size
 
         # Physical coordinates of the center of the cells
-        x = np.linspace(im_extent[0], im_extent[1], map_size) + 0.5 * dx - pos_star[0]
-        y = np.linspace(im_extent[2], im_extent[3], map_size) + 0.5 * dy - pos_star[1]
+        x = np.linspace(im_extent[0], im_extent[1], map_size) + 0.5 * dx - center[0]
+        y = np.linspace(im_extent[2], im_extent[3], map_size) + 0.5 * dy - center[1]
 
         xx, yy = np.meshgrid(x, y)
         rr = np.sqrt(xx ** 2 + yy ** 2)
diff --git a/pp_params.yml b/pp_params.yml
index 798b23b..6a62655 100644
--- a/pp_params.yml
+++ b/pp_params.yml
@@ -11,7 +11,7 @@ plot : # Plot parameters
 
 disk: # Disk speficic parameters
     enable    : False                 # Enable specific disk analysis
-    pos_star  : [1., 1., 1.]          # Position of the central star
+    center    : [0.5, 0.5, 0.5]       # Position of the center of the disk (in fraction of lbox)
     binning   : "log"                 # Kind of binning (lin : linear, log : logarithmic)
     mass_star : 1.                    # Mass of the central star
     nb_bin    : 100                   # Number of bins for averaged quantities