Spider CMB
Encyclopedia
Spider is a balloon-borne experiment designed to search for primordial gravity waves
imprinted on the cosmic microwave background (CMB). Measuring the strength of this signal puts limits on inflationary theory.
The Spider instrument consists of six degree-resolution telescopes cooled to liquid Helium temperature (4 K
) which observe at frequencies of 100 GHz, 150 GHz, and 220 GHz (corresponding to wavelengths of 3 mm, 2 mm, and 1.4 mm). Each telescope is coupled to a polarisation-sensitive transition-edge bolometer
array cooled to 250 mK
.
The first balloon flight of the experiment is planned for 2012 from McMurdo Station
, Antarctica, with support from NASA's Columbia Scientific Balloon Facility
. This Long Duration Balloon flight allows several weeks of mapping over about 10% of the sky. Further flights planned for successive seasons enable upgrades and changes to the modular telescope, and ever-improving depth for stronger results.
The primary science goals include:
Cosmic gravitational wave background
The cosmic gravitational wave background is a relic of the Cosmic inflation that can be measured directly or indirectly by examining the polarization of the Cosmic microwave background radiation...
imprinted on the cosmic microwave background (CMB). Measuring the strength of this signal puts limits on inflationary theory.
The Spider instrument consists of six degree-resolution telescopes cooled to liquid Helium temperature (4 K
Kelvin
The kelvin is a unit of measurement for temperature. It is one of the seven base units in the International System of Units and is assigned the unit symbol K. The Kelvin scale is an absolute, thermodynamic temperature scale using as its null point absolute zero, the temperature at which all...
) which observe at frequencies of 100 GHz, 150 GHz, and 220 GHz (corresponding to wavelengths of 3 mm, 2 mm, and 1.4 mm). Each telescope is coupled to a polarisation-sensitive transition-edge bolometer
Transition edge sensor
A transition edge sensor or TES is a type of cryogenic particle detector that exploits the strongly temperature-dependent resistance of the superconducting phase transition.-Principle of operation:...
array cooled to 250 mK
Kelvin
The kelvin is a unit of measurement for temperature. It is one of the seven base units in the International System of Units and is assigned the unit symbol K. The Kelvin scale is an absolute, thermodynamic temperature scale using as its null point absolute zero, the temperature at which all...
.
The first balloon flight of the experiment is planned for 2012 from McMurdo Station
McMurdo Station
McMurdo Station is a U.S. Antarctic research center located on the southern tip of Ross Island, which is in the New Zealand-claimed Ross Dependency on the shore of McMurdo Sound in Antarctica. It is operated by the United States through the United States Antarctic Program, a branch of the National...
, Antarctica, with support from NASA's Columbia Scientific Balloon Facility
Columbia Scientific Balloon Facility
The Columbia Scientific Balloon Facility is a NASA facility responsible for providing launch, tracking and control, airspace coordination, telemetry and command systems, and recovery services for unmanned, high altitude balloons...
. This Long Duration Balloon flight allows several weeks of mapping over about 10% of the sky. Further flights planned for successive seasons enable upgrades and changes to the modular telescope, and ever-improving depth for stronger results.
The primary science goals include:
- characterization of the curl-free component of the CMB polarization on the largest scales
- searching for the signature of inflationary gravitational waves in the CMB polarization
- characterization of the polarization properties of the emission from our own Milky Way Galaxy