1 / 18

Sarah Stoebner University of Hawai’i at Hilo Mentor: Billie Chitwood

Sarah Stoebner University of Hawai’i at Hilo Mentor: Billie Chitwood. Temperature Effects on the Pointing of Antennas at the Submillimeter Array. SMA Why? Background Project Results. Outline. The Submillimeter Array Mauna Kea, Hawai’i. Important Project. -Daytime observations

ondrea
Download Presentation

Sarah Stoebner University of Hawai’i at Hilo Mentor: Billie Chitwood

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Sarah Stoebner University of Hawai’i at Hilo Mentor: Billie Chitwood Temperature Effects on the Pointing of Antennas at the Submillimeter Array

  2. SMA • Why? • Background • Project • Results Outline

  3. The Submillimeter ArrayMauna Kea, Hawai’i

  4. Important Project -Daytime observations -Most temperature variation -Metal heats up it expands -Variation of expansion affects pointing -Pointing important for astronomical data -Other factors cause pointing errors -Correct for factors that cause large error -Pointing Model -Too expensive to correct for all

  5. Quadrapods

  6. Primary Reflector Reflector Mount Sensor

  7. Temperature Dataon July 25, 2007

  8. Snapshotson July 25, 2007 Snapshot of Jupiter at sunset (7:32PM) Snapshot of Jupiter a few hours later (10:13PM)

  9. Arcturus Altair Deneb Jupiter Vega

  10. Results In Azimuth: The pixel difference was 1.6 pixels With 1.252” per pixel the pointing error caused by temperature was 1.878” In Elevation: The pixel difference was 3.5 pixels With 1.252” per pixel the pointing error caused by temperature was 4.381”

  11. Acknowledgments • Billie Chitwood • Nimesh Patel • Erin Brassfield • SMA Staff • Sarah Anderson • Scott Seagroves • Hilary O’Bryan • This work has been supported by the National Science Foundation Science and Technology Center for Adaptive Optics, managed by the University of California at Santa Cruz under cooperative agreement No. AST - 9876783.

  12. Azimuth Error Elevation Error ΔEl = El´ + S cos(El) + I cos(Az) + I sin(Az) + I cos(2(Az)) + I sin(2(Az)) + Qel Other Pointing Errors ΔAz cos(El) = Az´ cos(El) + C + L sin (El) +I sin(El) sin(Az) + I sin(El) cos(Az) + I sin(El) sin(2(Az)) + I sin(El) cos(2(Az))+ M cos(El) sin(Az) + M cos(El) cos(Az) + M cos(El) sin(2(Az)) + M cos(El) cos(2(Az)) + M cos(El) sin(3(Az)) + M cos(El) cos(3(Az))+ Qaz +RMaz

More Related