Meaning: This quote by Frederick Reines, a renowned physicist, encapsulates the significance of reducing cosmic ray muon flux in order to conduct successful experiments in deep underground laboratories. To fully understand the quote, it's essential to delve into the context of cosmic ray muons and the role they play in scientific experiments.

Cosmic rays are high-energy radiation originating from outer space. They consist of protons, electrons, and other atomic nuclei. When these cosmic rays collide with particles in the Earth's atmosphere, they produce a shower of secondary particles, including muons. Muons are elementary particles similar to electrons but are around 200 times more massive. They are created in large quantities in cosmic ray showers and can penetrate deeply into the Earth's surface.

In the field of particle physics, muons are of particular interest due to their penetrating nature and their ability to interact weakly with matter. This makes them valuable for studying processes such as neutrino interactions and for conducting experiments that require penetrating radiation. However, the high flux of cosmic ray muons at the Earth's surface poses a significant challenge for experiments that demand low background radiation and precise measurements.

To address this challenge, researchers like Reines have turned to deep underground laboratories. These facilities are located deep beneath the Earth's surface, typically in mines or other underground structures, where they are shielded from cosmic ray muon flux. By conducting experiments in these underground environments, scientists can significantly reduce the interference caused by cosmic ray muons and other background radiation, thus enabling more precise measurements and observations.

Reines' statement emphasizes the necessity for researchers to become experts in the operation of deep underground laboratories in order to mitigate the impact of cosmic ray muon flux on their experiments. This expertise may encompass a range of skills, including the design and construction of underground facilities, the implementation of shielding technologies, and the development of specialized detectors capable of capturing elusive particles such as neutrinos.

Furthermore, Reines' work as a physicist is particularly noteworthy in the context of this quote. He was awarded the Nobel Prize in Physics in 1995 for his co-discovery of the neutrino, a fundamental particle that interacts with matter via the weak nuclear force. The discovery was made possible through the use of underground laboratories to reduce background radiation and isolate neutrino interactions.

In conclusion, Frederick Reines' quote underscores the critical role of reducing cosmic ray muon flux in the success of experiments that demand low background radiation. It highlights the expertise required to operate deep underground laboratories and emphasizes the significance of these facilities in enabling groundbreaking discoveries in the field of particle physics. By understanding the challenges posed by cosmic ray muons and the solutions offered by underground laboratories, researchers can continue to push the boundaries of scientific knowledge and make significant strides in understanding the fundamental particles and forces that govern the universe.