Did we just discover a new subatomic particle? Scientists are being super cautious.

These CERN physicists are being very, very cautious about today’s exciting news:

Here’s the news: Researchers using the Large Hadron Collider think they may have found evidence of a new subatomic particle. They’re being cautious because if their suspicion is confirmed, it will be a complete game changer for particle physics.

Why is that significant? Because when physicists discovered the Higgs boson in 2012, it capped off a decades-long search to confirm the existence of every subatomic particle theorized. A new subatomic particle would mean there are tiny components of matter that scientists have neither predicted existed nor observed before. That’s really cool.

It “would be a game changer” Gian Francesco Giudice, a CERN scientist, told Nature. The standard model of particle physics would no longer be the standard.

After the scientists discovered the Higgs — the subatomic particle that gives other particles their mass — the collider was shut down for two years. Physicists were both triumphant and a bit mournful. “With the Higgs, we thought we had touched the bottom,” Andre David, a research physicist, told Wired.

Just this last summer, the collider was started up again — this time with double the atom-smashing power — with the hope of finding bigger, newer, stranger subatomic particles. Or perhaps to find confirmation of a theory called supersymmetry, which postulates that every particle of matter has a corresponding partner particle with a slightly different spin. These supersymmetical particles might make up dark matter, a mysterious source of gravity that holds galaxies together and is apparently the most abundant source of matter in the universe.

According to the New York Times, it will take until the summer to come to a conclusive answer whether this new particle — believed to be a boson heavier than the Higgs — is real.