A detector in the field of research refers to a device or tool used to measure, quantitate, or detect the presence of a specific substance, signal, or phenomenon. Detectors can range from simple devices like thermometers or Geiger counters to more complex instruments like gas chromatographs or mass spectrometers. They are essential in many scientific disciplines, including chemistry, physics, biology, environmental science, and engineering, for analyzing samples, monitoring processes, and collecting data. Detectors can be based on various principles, such as optical, electrical, magnetic, or radioactive detection, and are crucial for advancing our understanding of the natural world and developing new technologies.