Arc Stroke

var config = {
    width: 800,
    height: 600,
    type: Phaser.AUTO,
    parent: 'phaser-example',
    scene: {
        create: create
    }
};

var game = new Phaser.Game(config);

function create ()
{
    var graphics = this.add.graphics();

    graphics.lineStyle(50, 0xffffff);

    graphics.beginPath();
    graphics.arc(400, 300, 200, Phaser.Math.DegToRad(0), Phaser.Math.DegToRad(360), false, 0.02);
    graphics.strokePath();
    graphics.closePath();

    graphics.beginPath();
    graphics.lineStyle(40, 0xff00ff);
    graphics.arc(400, 300, 200, Phaser.Math.DegToRad(0), Phaser.Math.DegToRad(360), true, 0.02);
    graphics.strokePath();
    graphics.closePath();
}