motorcycles after you request them to stop? There are a lot of children who play outside in our neighborhood. Three of them our mine. I am so afraid one of them will be ran over while the neighbors pop wheelies and speed up and down our street.
It isn't a hole!!! When a massive star dies after using all of its elements to make energy it goes dark the gases remaining are pulled by gravity into a very dense sphere - a black hole. The sphere has a very high mass which creates a very high gravitational pull on the space around it. The gravity is so high that it will even pull in the photons of light from other stars resulting in a black spot in the universe thus it was called a black hole.
No permanent installation, and you'll have a picture of the intruder. I think that's better than just detecting the intrusion.
State and local laws vary, however, the general rule (NFPA 101 Life Safety Code) requires all dormitories to have fire alarms unless it is under 3 stories high and all rooms have exterior exit access (i.e., at grade or to an open balcony).
