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Jun 23 – 27, 2025
Eckhardt Research Center
America/Chicago timezone

Frequency-Selectable Laser Source (FLS) Calibrator for CMB Bandpass Characterization

Jun 23, 2025, 4:00 PM
15m
401 (ERC)

401

ERC

Parallel Session Parallel Session B

Speaker

Lauren Saunders (Fermi National Accelerator Laboratory)

Description

One of the biggest challenges for Cosmic Microwave Background (CMB) experiments comes from our detector bandpass calibration. Uncertainties in bandpass can severely limit our measurements by limiting foreground removal and spectral fitting, which is particularly important for high-$\ell$ observations like cluster science using the Sunyaev-Zeldovich (SZ) effect. Currently, CMB experiments typically use a Fourier Transform Spectrometer (FTS) to measure the detector bandpasses. However, the resolution of the FTS is dependent on the length of the interferometer arms, leading to a need for increasingly large FTS instruments as CMB experiments require tighter constraints on detector bandpasses. Additionally, systematic effects like shifts in bandpass shape from uneven illumination from the FTS further limit the calibration uncertainties. As a complement to the FTS, we have developed a Frequency-selectable Laser Source (FLS) calibrator, which uses a laser with adjustable frequency housed in a calibrator that allows for varying degrees of laser power attenuation. We present several tests used to characterize the first prototype design of the FLS calibrator, as well as the improvements to the calibrator design currently underway.

Would you be interested in presenting a poster if the conference is oversubcribed? Yes

Primary author

Lauren Saunders (Fermi National Accelerator Laboratory)

Co-authors

Jeff McMahon (University of Chicago) Sara Simon (Fermi National Accelerator Laboratory) Shreya Sutariya (University of Chicago)

Presentation materials

There are no materials yet.