No it is not haraam to become a physicist or an astrophysicist or an astronomer. Science is only exploring what God has created. And indeed, we are told in many Hadith and even in the Qur'an to seek knowledge whenever possible. It is this that made the first generation of Muslims get into the Golden age of Islam. 

Also, the God Particle, the Higgs Boson, is just a name given to it. It does not mean that it is literally God. It is named 'The God Particle' because it is so hard to find.