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.
And it is He Who spread out the earth, and placed therein firm mountains and rivers and of every kind of fruits He made Zawjain Ithnain (two in pairs - may mean two kinds or it may mean: of two varieties, e.g. black and white, sweet and sour, small and big). He brings the night as a cover over the day. Verily, in these things, there are Ayat (proofs, evidence, lessons, signs, etc.) for people who reflect.
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. Following is from wikipedia
Lederman said he gave the Higgs boson the nickname "The God Particle" because the particle is "so central to the state of physics today, so crucial to our final understanding of the structure of matter, yet so elusive,"[5] "And the Lord said, Behold".[6][7][8] The text in the book explain "the publisher wouldn't let us call it the Goddamn Particle, though that might be a more appropriate title, given its villainous nature and the expense it is causing.
