Circuit to apply power to the arduino when a push button is triggered

Hello all.
I'm trying to find a schematic diagram to understand how we can apply power to the arduino for let's say 1 minute when a push button is trigerred.

My project is to make a letter box letter detection.
There will be a mercury contactor ( the push button) to make the contact when it is shaked by a letter falling
Once the contact is made, I would like the arduino to be connected to 5v and boot on a wifi skech to send the information to an ip address. After 1 minute, I would like the 5v to be disconnecteed from circuitry and the arduino to power off.
It is probably a timer schematic but I need someone to point me into the right direction

So, use two Arduinos.

Paul

The idea is to save on battery
I found a solution with Push on off latching circuit using a push button switch | 555 timer projects - YouTube
1 button to power
1 GPIO to shut down

But the NE555 still needs to be powered.

I'm trying to find something which completely switch to zero consumption when the system is not shaked
To save the lipo battery

In that case, try a micro switch with a very long actuator lever the letter can hit on. The weight of the letter would keep the lever pressed.

Paul

Found my solution

Google "ESP8266 dash button"
No Arduino or 555 needed.
Leo..

Use a P-channel MOSFET, where the switch can trigger the gate, power up the Arduino, the Arduino then keeps the gate triggered, and when it's time it releases the gate to turn everything off.
Pololu.com makes a few variations
https://www.pololu.com/product/2808

The one I used is Here.