How to logout from 2 different web application independantly ?

See more:

C#

ASP.NET

session

Hello,
Everyone i am new to session handling.Here I have developed web application where user can login using windows authentication.Also I have another web application which also uses windows authentication.i.e both application have same user name and password and both can login simultaneously.Problem is that when i logout from my web application it automatically logout from another application.
Is there is any solution please share with me.

What I have tried:

following code inside the session_start event

string windowsLogin = this.Context.Request.LogonUserIdentity.Name;


            //Normally if the domain is present you get a string like DOMAINNAME\username, remove the domain
            int hasDomain = windowsLogin.IndexOf(@"\");
            if (hasDomain > 0)
            {
                windowsLogin = windowsLogin.Remove(0, hasDomain + 1);
            } //end if 
           Session["UserName"] = windowsLogin;

then function for logout is javascript function

function Logout() {
          try {

              if (window.XMLHttpRequest) {

                  document.execCommand("ClearAuthenticationCache");

              }

              else {
                  alert("This feature requires Internet Explorer 6.0 Service Pack 1 or above. " + "Please close all browser windows in order to complete the logout process.");
              }
          }
          catch (e) {
              alert("This feature requires Internet Explorer 6.0 Service Pack 1 or above. " + "Please close all browser windows in order to complete the logout process.");
          }
          //netscape.security.PrivilegeManager.enablePrivilege("UniversalBrowserWrite");
          //self.close();
          window.close();

      }