Controlling 220v sensor

Hi,

I have bought PIR sensor ( http://www.steinel.de/en/Motion-Detectors/Overview-Motion-Detectors/Infrared-motion-detector-IS-1-White.html ) and i’m wondering if anyone knows how could i be able to use it with Arduino.
I want to make an alarm system with it but i don’t know how could i be able to control it with Arduino, sensor is connected to 220 V (L) and when it detect something it gives 220 V (L’). Is it even possible to use it like this sensor ?
( http://archive.wired.com/geekdad/2012/09/using-motion-detectors-with-an-arduino/ )
Thank you for your answers

Drive a small AC relay with the output from the detector. Wire the relay contacts like a switch to an input. There are also ways of doing that with optoisolators although I don't know the details. At any rate you need isolation between the mains and Arduino.

https://www.google.com/search?q=opto+isolator+for+220v&rlz=1C1GPCK_enUS504US504&espv=2&tbm=isch&tbo=u&source=univ&sa=X&ei=RU_qU-T_BIbtoATOvYDwDw&ved=0CE0QsAQ&biw=864&bih=438&dpr=2

Thank you very much, i will try to do that, really thanks for giving me enough information to start =)