A Comparison of Actual and Black-Body Temperatures

Charles C. Bidwell

doi:10.1103/physrev.3.439

Clouds over the Tropial Atlantic during July and August 1970

Bulletin of the American Meteorological Society ◽

10.1175/1520-0477-55.6.587 ◽

1974 ◽

Vol 55 (6) ◽

pp. 587-596 ◽

Cited By ~ 3

Author(s):

R. Madden ◽

L. Sapp ◽

E. Zipser

Keyword(s):

Spatial Distribution ◽

Satellite Data ◽

Relative Frequency ◽

Black Body ◽

Tropical Atlantic ◽

Body Temperatures ◽

Cloud Clusters ◽

Weather Observations ◽

High Clouds

Nimbus IV radiance measurements in the 10.5–12.5-μm window channel from the tropical Atlantic during July and August 1970 are studied. The relative frequency of cold, and presumably high clouds, is determined. The average spatial distribution of equivalent black-body temperatures associated with 38 cloud clusters is reported. Ship cloud and weather observations are studied in conjunction with the satellite data. By combining the evidence provided by the satellite and ship observations, a model of typical clouds and weather associated with cloud clusters is proposed for further study.

Download Full-text

The ROSAT observations of classical novae

International Astronomical Union Colloquium ◽

10.1017/s0252921100038872 ◽

1996 ◽

Vol 158 ◽

pp. 289-289

Author(s):

M. Orio ◽

H. Ögelman ◽

S. Balman

Keyword(s):

Thin Shell ◽

Black Body ◽

Archival Data ◽

X Rays ◽

Body Temperatures ◽

Hydrogen Burning ◽

X Ray ◽

Classical Novae ◽

Upper Limits ◽

The Galaxy

We observed a number of classical and recurrent novae in the Galaxy and the LMC with the ROSAT X-ray telescope and searched the archival data for other serendipitous observations. Preliminary results show that only 9 out of 37 observed objects were bright enough in X-rays to be detected with ROSAT, either in outburst or at quiescence.Three basic mechanisms can cause X-ray emission from classical or re-current novae. The first is hot hydrogen burning in a thin shell of the remnant envelope left on the white dwarf after the nova explosion. Hydrogen burning post-novae should be blackbody like emitters at nearly Eddington luminosity (as per the ‘supersoft’ X-ray sources). In our sample, only GQ Mus (Nova Mus 1983, see Ögelman et al. 1993; Shanley et al. 1995) and V1974 Cyg 1992 (Krautter et al. 1996) had these characteristics. Remarkably, among 10 LMC novae that had an outburst in the last 47 yr none was detected as a ‘supersoft’ X-ray source. The 3 σ upper limits for the black-body temperatures of the post-nova white dwarfs are mainly in the range 20… 30 eV. A post-nova can also emit X-rays because of shocks occurring in the ejected shell (e.g. O’Brien et al. 1994). Three out of four classical novae that were observed in outburst displayed a hard X-ray component in the ROSAT energy band, which might be due to a shocked shell. Finally, X-ray emission is expected from quiescent nearby novae because of accretion. Only four nearby accreting sources were detected; the ROSAT upper limits for the non-detected quiescent novae are Lx < 1031… 1032 ergs−1, assuming a thermal plasma at kT = a few keV.

Download Full-text

Calibration and Tests of Commercial Wireless Infrared Thermometers

Applied Engineering in Agriculture ◽

10.13031/aea.12577 ◽

2018 ◽

Vol 34 (4) ◽

pp. 647-658 ◽

Cited By ~ 2

Author(s):

Paul D. Colaizzi ◽

Susan A. O’Shaughnessy ◽

Steven R. Evett

Keyword(s):

Agricultural Research ◽

Canopy Temperature ◽

Longwave Radiation ◽

Radiation Energy ◽

Black Body ◽

Limited Range ◽

Target Temperature ◽

Body Temperatures ◽

Wireless Data Transmission ◽

Temperature Controlled

Abstract. Applications of infrared thermometers (IRTs) in large agricultural fields require wireless data transmission, and IRT target temperature should have minimal sensitivity to internal detector temperature. To meet these objectives, a prototype wireless IRT system was developed at USDA Agricultural Research Service, Bushland, Texas, and commercialized by Dynamax, Inc., Houston, Texas. The objective of this article was to calibrate and test the Dynamax, Inc. system. Following deployment in an irrigated field during the 2015 crop season, 26 IRTs were calibrated and tested in a temperature-controlled room. The IRTs measured a black body target temperature controlled at 15°C to 55°C in 5°C increments, and for each range of black body temperatures, ambient room temperatures were controlled at 15°C, 20°C, 25°C, 35°C, and 45°C under isothermal and steady-state conditions. Discrepancies between uncalibrated IRT and black body temperatures varied by IRT and had root mean squared errors (RMSE) between 0.25°C and 1.51°C, mean absolute errors (MAE) between 0.19°C and 1.17°C, and mean bias errors (MBE) between -0.66°C and 0.16°C. A calibration equation was derived from the longwave radiation energy balance of the IRT internal detector, and sensor-specific calibrations reduced discrepancies for all IRTs, with RMSE between 0.16°C and 0.28°C, MAE between 0.12°C and 0.21°C, and absolute MBE less than 0.05°C. A generic calibration was derived by pooling all sensor-specific calibrations, and reduced discrepancies for all but five IRTs, but these were very marginal compared with no calibration. Therefore, the generic calibration did not appear justified, but sensor-specific calibrations were justified for most IRTs. The IRTs were again deployed in the irrigated field and measured corn canopy temperature in 2016. Crop evapotranspiration (ETc) was calculated using measurements from one IRT and compared to ETc measured by a large weighing lysimeter. The choice of calibration (none, generic, or sensor-specific) had little impact on calculated ETc, which was likely related to a limited range of target and sensor body temperature differences in the field (mostly +10°C), in contrast to those in the temperature-controlled room (up to +40°C) Keywords: Canopy temperature, Crop management, Evapotranspiration, Irrigation, Remote sensing, Sensors.

Download Full-text

How many equivalent black-body temperatures are there?

Journal of Thermal Biology ◽

10.1016/0306-4565(81)90045-0 ◽

1981 ◽

Vol 6 (1) ◽

pp. 59-60 ◽

Cited By ~ 15

Author(s):

George S. Bakken

Keyword(s):

Black Body ◽

Body Temperatures

Download Full-text

Comparison of Six Supersoft X-ray Binaries

Symposium - International Astronomical Union ◽

10.1017/s0074180900117929 ◽

1999 ◽

Vol 190 ◽

pp. 239-240

Author(s):

A. P. Cowley ◽

P. C. Schmidtke ◽

J. B. Hutchings ◽

D. Crampton

Keyword(s):

Column Density ◽

Galactic Plane ◽

Black Body ◽

Body Temperatures ◽

X Ray ◽

Distinct Class ◽

The Galaxy ◽

X Ray Absorption ◽

X Ray Binaries ◽

Very High

The supersoft X-ray sources are a distinct class of X-ray sources identified by ROSAT. They are characterized by very high luminosities (Lbol ~ 1038 ergs s−1) and black body temperatures of kT~ 30–60 eV. These sources are easily detected in the LMC and SMC because of the low column density of absorbing H gas. Thus, the samples found there are complete. They are much more difficult to find in the Galaxy due to soft X-ray absorption in the galactic plane.

Download Full-text