Introduction
The Limiting Magnitude Study is a current research project of Olivia Chiarini, funded by a UMBC URA. When making observations with the UMBC Observatory, we have to account for the limitations of our observatory, given that we are looking through an atmosphere, located around Baltimore, and have imperfect equipment. Because of this, we must properly understand the effects of these factors on our observations, and develop pipelines to correct for said factors. One standard quantity for ground based observatories is the limiting magnitude, which defines the faintest celestial objects we can reasonably expect to detect on a given night. This quantity is often calculated by observing dim sets of stars, and seeing how accurately we can calculate their relative magnitudes. This is tested against a set of papers by Dr. Arlo Landolt, which lists some constant star fields and their magnitudes (often called Photometric Standards). Given data from these photometric standards, we seek to develop a pipeline that takes our frames and transforms them into calibrated sets of data, called science frames. The first step to utilizing this pipeline involves taking of calibration frames, frames that seek to isolate possible sources of unwanted signal in our camera such as thermal noise, bias from our cameras, or dust and particles in our optical system. With these frames, we can create a software pipeline to process data from photometric standards in combination with calibration frames to calculate instrument magnitudes, a relative value that is dependent on our location and equipment. After this, we can account for the effects of our atmosphere, and translate our measurements to the traditional magnitude system. From here, we can compare our calculated magnitudes to those published by Landolt, noting at what magnitudes our values begin to decrease in accuracy as we lose the ability to observe more faint objects. With a tested and accurate data reduction pipeline, the UMBC Observatory gains the ability to calibrate and observe stellar sources outside of relative measurements, which can be used to further future projects.
Author: Olivia Chiarini
Editor: Jacob
Date: 20240910