Radiometer System to Map the Cosmic Background Radiation

PDF Version Also Available for Download.

Description

We have developed a 33 GHz airborne radiometer system to map large-scale angular variations in the temperature of the 3 K cosmic background radiation. A ferrite circulator switches a room-temperature mixer between two antennas pointing 60{sup o} apart in the sky. In forty minutes of observing, the radiometer can measure the anisotropy of the microwave background with an accuracy of {+-} 1 m{sup o}K rms, or about one part in 3000 of 3 K. The apparatus is flown in a U-2 jet to 20 km altitude where 33 GHz thermal microwave emission from the atmosphere is at a low level. ... continued below

Creation Information

Gorenstein, Marc V.; Muller, Richard A.; Smoot, George F. & Tyson,J. Anthony November 1, 1977.

Context

This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided by UNT Libraries Government Documents Department to Digital Library, a digital repository hosted by the UNT Libraries. More information about this article can be viewed below.

Who

People and organizations associated with either the creation of this article or its content.

Publisher

Provided By

UNT Libraries Government Documents Department

Serving as both a federal and a state depository library, the UNT Libraries Government Documents Department maintains millions of items in a variety of formats. The department is a member of the FDLP Content Partnerships Program and an Affiliated Archive of the National Archives.

Contact Us

What

Descriptive information to help identify this article. Follow the links below to find similar items on the Digital Library.

Description

We have developed a 33 GHz airborne radiometer system to map large-scale angular variations in the temperature of the 3 K cosmic background radiation. A ferrite circulator switches a room-temperature mixer between two antennas pointing 60{sup o} apart in the sky. In forty minutes of observing, the radiometer can measure the anisotropy of the microwave background with an accuracy of {+-} 1 m{sup o}K rms, or about one part in 3000 of 3 K. The apparatus is flown in a U-2 jet to 20 km altitude where 33 GHz thermal microwave emission from the atmosphere is at a low level. A second radiometer, tuned to 54 GHz near oxygen emission lines, monitors spurious signals from residual atmospheric radiation. The antennas, which have an extremely low side-lobe response of less than -65 dB past 60{sup o}, reject anisotropic radiation from the earth's surface. Periodic interchange of the antenna positions and reversal of the aircraft's flight direction cancel equipment-based imbalances. The system has been operated successfully in U-2 aircraft flown from NASA-Ames at Moffett Field, California.

Source

  • Journal Name: Review of Scientific Instruments; Journal Volume: 49; Journal Issue: 4; Related Information: Journal Publication Date: 1978

Language

Item Type

Identifier

Unique identifying numbers for this article in the Digital Library or other systems.

  • Report No.: LBL--6493
  • Grant Number: DE-AC02-05CH11231
  • Office of Scientific & Technical Information Report Number: 893056
  • Archival Resource Key: ark:/67531/metadc883734

Collections

This article is part of the following collection of related materials.

Office of Scientific & Technical Information Technical Reports

What responsibilities do I have when using this article?

When

Dates and time periods associated with this article.

Creation Date

  • November 1, 1977

Added to The UNT Digital Library

  • Sept. 21, 2016, 2:29 a.m.

Description Last Updated

  • Sept. 30, 2016, 12:42 p.m.

Usage Statistics

When was this article last used?

Yesterday: 0
Past 30 days: 1
Total Uses: 10

Interact With This Article

Here are some suggestions for what to do next.

Start Reading

PDF Version Also Available for Download.

Citations, Rights, Re-Use

Gorenstein, Marc V.; Muller, Richard A.; Smoot, George F. & Tyson,J. Anthony. Radiometer System to Map the Cosmic Background Radiation, article, November 1, 1977; Berkeley, California. (digital.library.unt.edu/ark:/67531/metadc883734/: accessed August 17, 2017), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.