There's no way a rat would sit tight that long! They're quick as a flash unless half dead.
Air riffle, cage trap, dogs/ferrets, break back trap or glue boards. Shooting a rat in a cage trap with an air rifle isn't quite as simple as you'd think.
I quite like glue boards. I check morning and night, mice and rats are easily killed because they're held still. None of it's nice, shooting is Quite humane, but rats are hard to shoot because they're so quick and wary. Poison is probably the least humane, but easiest. Break back traps can work well, but you can catch non target species :-( even if set up in a tunnel. Non target species caught in glue traps can be removed with veg oil.
Good luck!