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Abstract We present a beam pattern measurement of the Canadian Hydrogen Intensity Mapping Experiment (CHIME) made using the Sun as a calibration source. As CHIME is a pure drift-scan instrument, we rely on the seasonal north–south motion of the Sun to probe the beam at different elevations. This semiannual range in elevation, combined with the radio brightness of the Sun, enables a beam measurement that spans ∼7200 square degrees on the sky without the need to move the telescope. We take advantage of observations made near solar minimum to minimize the impact of solar variability, which is observed to be <10% in intensity over the observation period. The resulting data set is highly complementary to other CHIME beam measurements—both in terms of angular coverage and systematics—and plays an important role in the ongoing program to characterize the CHIME primary beam.
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Determining the Orbital Angular Momentum of a Vortex Beam Using the Strong Field Approximation
Using a Classical Trajectory Monte Carlo Simulation and a unique setup with a planewave beam perpendicular to a Laguerre-Gaussian beam, the strong field approximation is used to determine the angular momentum of the vortex beam.
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- Award ID(s):
- 2208040
- PAR ID:
- 10498016
- Publisher / Repository:
- Optica Publishing Group
- Date Published:
- ISBN:
- 978-1-957171-29-6
- Page Range / eLocation ID:
- LD1.2
- Format(s):
- Medium: X
- Location:
- Tacoma, Washington
- Sponsoring Org:
- National Science Foundation
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