how do i run given code in a new window?

Hi All.
I have this code on a button click event:
Protected Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Response.ContentType = "Application/pdf"
        'Get the physical path to the file.
        Dim FilePath As String = MapPath("acrobat.pdf")
        'Write the file directly to the HTTP output stream.
        Response.WriteFile(FilePath)
        Response.End()
    End Sub
 The above code opens a pdf file in the browser as i want it to. However, i would like it to open it in a new window. How can that be achieved?
 
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