Rapid alternate detection system of the Rothney Astrophysical Observatory.

Area of Science:

• Astronomy
• Astrophysics
• Instrumentation

Background:

• Differential photometry is crucial for detecting subtle changes in stellar brightness.
• Existing photometry systems can be affected by atmospheric transparency and sky brightness variations.
• The Rothney Astrophysical Observatory sought to improve observational accuracy and reliability.

Purpose of the Study:

• To design and test a new differential variable-star photometry system.
• To minimize the impact of environmental factors on photometric measurements.
• To enhance the robustness of stellar photometry under challenging conditions.

Main Methods:

• A single telescope, photometer, and detector were utilized.
• Gated pulse-counting electronics synchronized to a chopped secondary mirror were employed.
• The mirror rapidly alternated between the variable star, comparison star, and sky-background regions.

Main Results:

• The system demonstrated insensitivity to transparency, sky-brightness, and detector-sensitivity variations on longer timescales.
• The photometry system proved effective under significant cloud cover (up to three magnitudes).
• Rapid alternate detection enabled stable differential measurements.

Conclusions:

• The developed system offers improved accuracy and reliability for variable-star photometry.
• This instrumentation is valuable for astronomical research, especially in variable-star studies.
• The system's resilience to environmental changes expands its applicability.