How would i use this to tell a local script this is on a players head?

How would i use this to tell another players script that the lazer is in contact with there head? i have tried several things such as mouse.Parent.Head, but it wont work for me!

--[[Super Util]]--
function WaitForChild(parent,...)
	local debugPrint = false
	for _, i in ipairs({...}) do
		if type(i)=='boolean' then
			debugPrint = i
		else
			while not parent:FindFirstChild(i) do  
				wait(1/30) 
				if debugPrint then
					print(script.Name..':'..parent.Name..' Waiting for '.. i)
				end
			end
			parent=parent[i]
		end
	end
	return parent
end

function ForEach(parent,func)
	if type(parent)=='table' then
		for _,i in pairs(parent) do
			func(i)
		end
	else
		for _,i in pairs(parent:GetChildren()) do
			func(i)
		end
	end
end

function MakeValue(class,name,value,parent)
	local temp = Instance.new(class)
	temp.Name = name
	temp.Value = value
	temp.Parent = parent
	return temp
end	

function TweenProperty(obj, propName, inita, enda, length,sentinel)
	local startTime = tick()
	local mySentinel = sentinel.Value
	local diff = enda-inita
	while tick()-startTime<length and mySentinel==sentinel.Value do
		obj[propName] = (((tick()-startTime)/length)*diff)+inita
		wait(1/30)
	end
	obj[propName] = enda	
end

--[[Constants]]--

--[[Workspace Variables]]--
local Tool = script.Parent
local Handle = WaitForChild(Tool,'Handle')
local LazerSound = WaitForChild(Handle,'Lazer')
--[[Script Variables]]--

--[[Script Functions]]--

function CastLightRay(startPos,endPos,color,segLength,segSpeed,parts,effectfunc)
	local part, nend = game.Workspace:FindPartOnRay( Ray.new(startPos,(endPos-startPos).unit*999.999),Tool.Parent)
	if nend then endPos = nend end
	
	if part and part.Parent then
		if part.Parent:FindFirstChild('Humanoid') and part.Parent ~=Tool.Parent then
			effectfunc(part.Parent.Humanoid,(endPos-startPos).unit)
		elseif part.Parent.Parent and part.Parent.Parent:FindFirstChild('Humanoid')  and part.Parent.Parent~=Tool.Parent then
			effectfunc(part.Parent.Parent.Humanoid,(endPos-startPos).unit)
		end
	end	
	
	
	local numSegments = math.floor(math.min((startPos-endPos).magnitude/segLength,50))
	local initNumParts = #parts
	for i=numSegments,initNumParts,1 do
		if parts[i] then
			parts[i]:Destroy()
			parts[i]=nil
		end
	end
	for i=1,numSegments,1 do
		if not parts[i] then
			parts[i] = Instance.new('Part')
			parts[i].Parent = Tool
			parts[i].Anchored = true
			parts[i].FormFactor = 'Custom'
			parts[i].Size = Vector3.new(0,0,segLength)
			parts[i].CanCollide = false
			local tlight = Instance.new('PointLight')
			tlight.Name = 'Light'
			tlight.Parent = parts[i]
			
		end
		parts[i].BrickColor = color
		parts[i]:WaitForChild('Light').Color = color.Color
		parts[i].Light.Range =((math.sin(tick()*3)+1)*1)+5
		parts[i].Light.Brightness =((math.sin(tick()*3)+1)*1)+1

		parts[i].CFrame = CFrame.new(((i-.4)*(endPos-startPos).unit*segLength)+startPos,endPos)

	end
	
	return parts
end

--[[Running Logic]]--
local equipped = false
local rayparts = {}
local ColorChoices = {BrickColor.new('Bright red')}
local StartOffset = {Vector3.new(-.45,0,0),Vector3.new(0,0,0),Vector3.new(.45,0,0)}
local oldC0 =nil
local nweld
local EffectFunctions = 
{
	function(hum,dir) hum:TakeDamage(1) end,
	function(hum,dir) hum:TakeDamage(-1) end,
	function(hum,dir) 
		if hum.Torso then
			local nforce = Instance.new('BodyForce')
			nforce.force = dir*3000
			nforce.Parent = hum.Torso
			hum.Sit = true
			game.Debris:AddItem(nforce,.2)
			Delay(.2,function() hum.Sit = false end)
		end
	end
}
Tool.Equipped:connect(function(mouse)
	--game.Players.LocalPlayer:GetMouse()
	Spawn(function()
		local colorChoice = 1
		if not Tool.Parent:FindFirstChild('Torso') or not Tool.Parent.Torso:FindFirstChild('Right Shoulder') or not Tool.Parent:FindFirstChild('Humanoid') then return end
		LazerSound:Play()
		nweld = Tool.Parent.Torso['Right Shoulder']
		oldC0 = nweld.C0
		nweld.CurrentAngle = 0
		nweld.DesiredAngle = 0
		nweld.MaxVelocity = 0
		mouse.Button1Down:connect(function()
			colorChoice=colorChoice+1
			if colorChoice>#ColorChoices then colorChoice =1 end
			LazerSound.Pitch = .75+((colorChoice*.25)*3)
		end)
		equipped = true
		while equipped and Tool.Parent:FindFirstChild('Torso') do
			local tframe = Tool.Parent.Torso.CFrame
			tframe = tframe + tframe:vectorToWorldSpace(Vector3.new(1, 0.5, 0))
			local taim = mouse.Hit.p -( tframe.p )
			nweld.C0 = (CFrame.new(Vector3.new(),tframe:vectorToObjectSpace(taim))*CFrame.Angles(0,math.pi/2,0))+Vector3.new( 1, 0.5, 0 )
			rayparts = CastLightRay(Handle.CFrame.p+Handle.CFrame:vectorToWorldSpace(StartOffset[colorChoice]),mouse.Hit.p,ColorChoices[colorChoice], 5, .2,rayparts, EffectFunctions[colorChoice])
			LazerSound.Volume = ((math.sin(tick()*3)+1)*.25)+.25
			wait()
		end
		nweld.C0 =oldC0
		LazerSound:Stop()
	end)
end)

Tool.Unequipped:connect(function(mouse)
	equipped= false
	LazerSound:Stop()
	for i=1,50,1 do
		if rayparts[i] then
			rayparts[i]:Destroy()
			rayparts[i]=nil		
		end
	end
	if nweld then
		nweld.MaxVelocity =.15
		nweld.C0 =oldC0
	end
	
end)