Astrophysics (Index)About

bolometer

(instrument measuring heat produced by radiation)

A bolometer is an instrument for measuring electromagnetic radiation by allowing the radiation to heat a metal whose electrical resistance is dependent upon its temperature. As the material heats, the change in resistance is noted. Bolometers measure a relatively wide range of frequencies, thus are more suited to measuring energy over a wide range or estimating the total incident energy from a source. Bolometers are not necessarily the most sensitive instruments at some frequencies. They can be made competitive in the submillimeter to 1 mm range (far infrared). To achieve sensitivity, such bolometers are run near absolute zero. Micro-bolometers are used for imaging, with on the order of 100 × 100 pixels, and more recently approaching 1000 × 1000.

Note that the adjective bolometric which has the obvious meaning "involving bolometers", is also very often used to indicate the total of all EMR, e.g., from a source. This is the intended meaning in terms like bolometric correction, bolometric luminosity, and bolometric magnitude. This came about because bolometers do indeed measure the power of the EMR striking it across a wide band, wider than many other instruments, though they are not complete in that regard, and also, an Earth-bound bolometer will necessarily miss radiation not within atmospheric windows.


(instrument type,EMR,submillimeter)
Further reading:
http://en.wikipedia.org/wiki/Bolometer

Referenced by pages:
ACBAR
Atacama Cosmology Telescope (ACT)
Atacama Pathfinder Experiment (APEX)
Atacama Submillimeter Telescope Experiment (ASTE)
AzTEC-3
bolometric luminosity (LBol)
BOOMERanG
CMB Stage-4 (CMB-S4)
EBEX
focal plane array (FPA)
front end instrument
Green Bank Telescope (GBT)
GISMO
James Clerk Maxwell Telescope (JCMT)
LSPE-SWIPE
MAXIMA
MUSTANG
QUaD
QUBIC
radiometer
SCUBA
Swedish-ESO Submillimetre Telescope (SEST)
SOFIA
South Pole Telescope (SPT)
superconducting tunnel junction (STJ)
transition edge sensor (TES)

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