Scripting Reference
ParticleEmitter.useWorldSpace

var useWorldSpace : boolean

Description

If enabled, the particles don't move when the emitter moves. If false, when you move the emitter, the particles follow it around.

JavaScript 
particleEmitter.useWorldSpace = true;
using UnityEngine;
using System.Collections;

public class example : MonoBehaviour {
    void Example() {
        particleEmitter.useWorldSpace = true;
    }
}
import UnityEngine
import System.Collections

class example(MonoBehaviour):

    def Example():
        particleEmitter.useWorldSpace = true