Non-thermal emission from the interaction of extragalactic jets with stars

An intriguing question about extragalactic jets is why they are so few being seen at optical wavelengths, or equivalently, why the cutoff frequency of the synchrotron radiation is generally not in the optical, but rather in the infrared or even in the sub- millimeter domain. The answer is undoubtedly related to the efficiency of the acceleration of the relativistic electrons responsible for the synchrotron emission. The presence of a break at low frequency somewhere in the synchrotron spectrum is another feature that constrains the model parameters, but its precise location is unknown for most jets, because of the lack of photometry in the millimeter domain. It was thus necessary to fill the gap between radio and optical wavelengths in the synchrotron spectrum of optical jets. The required observation had to be of high sensitivity and high spatial resolution (of the order of 1″). Another reason for observing at millimeter wavelengths is that molecular lines and thermal emission from cold dust are detectable in this frequency range.

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Blazars: Clues to Jet Physics

Symposium - International Astronomical Union ◽

10.1017/s0074180900161844 ◽

1999 ◽

Vol 194 ◽

pp. 113-122

Author(s):

Rita M. Sambruna

Keyword(s):

Thermal Emission ◽

Jet Physics ◽

Spectral Energy ◽

Jet Formation ◽

Ionized Gas ◽

Extragalactic Jets ◽

Radiative Power ◽

Crucial Information ◽

Γ Rays ◽

Jet Structure

Being dominated by non-thermal emission from aligned relativistic jets, blazars allow us to elucidate the physics of extragalactic jets, and, ultimately, how energy is extracted from the central black hole. Crucial information about jet structure is provided by the spectral energy distributions from radio to γ-rays, their trends with luminosity, and correlated multifrequency variability. Since blazar jets have broad implications for all radio-loud (and possibly radio-quiet) AGNs, we also need to understand their circumnuclear structure, especially the details of the physical and dynamical conditions of the highly ionized gas on sub-pc scales, which could be directly related to jet formation and radiative power. Eventually, the bulk of information provided by blazars will help us clarify the origin of the radio-loud/radio-quiet AGN dichotomy, one of the most outstanding open issues of extragalactic astrophysics.

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Measurement of lattice parameter at the nanometer scale using convergent-beam microdiffraction from a thermal emission source

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100149283 ◽

1993 ◽

Vol 51 ◽

pp. 690-691

Author(s):

W. T. Pike

Keyword(s):

Electron Microscope ◽

Transmission Electron Microscope ◽

Thermal Emission ◽

Lattice Parameter ◽

Scanning Transmission Electron Microscope ◽

Emission Source ◽

Device Structure ◽

Transmission Electron ◽

Scanning Transmission ◽

Convergent Beam

With the advent of crystal growth techniques which enable device structure control at the atomic level has arrived a need to determine the crystal structure at a commensurate scale. In particular, in epitaxial lattice mismatched multilayers, it is of prime importance to know the lattice parameter, and hence strain, in individual layers in order to explain the novel electronic behavior of such structures. In this work higher order Laue zone (holz) lines in the convergent beam microdiffraction patterns from a thermal emission transmission electron microscope (TEM) have been used to measure lattice parameters to an accuracy of a few parts in a thousand from nanometer areas of material.Although the use of CBM to measure strain using a dedicated field emission scanning transmission electron microscope has already been demonstrated, the recording of the diffraction pattern at the required resolution involves specialized instrumentation. In this work, a Topcon 002B TEM with a thermal emission source with condenser-objective (CO) electron optics is used.

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Thermal Emission and Curing Efficiency of LED and Halogen Curing Lights

Yearbook of Dentistry ◽

10.1016/s0084-3717(08)70037-0 ◽

2006 ◽

Vol 2006 ◽

pp. 39-40 ◽

Cited By ~ 1

Author(s):

P.C. Belvedere

Keyword(s):

Thermal Emission

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Hydrodynamical Simulations of Extragalactic Jets

EAS Publications Series ◽

10.1051/eas:2001010 ◽

2001 ◽

Vol 1 ◽

pp. 75-87

Author(s):

J.M. Martí

Keyword(s):

Extragalactic Jets ◽

Hydrodynamical Simulations

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Application of Backside Photo and Thermal Emission Microscopy Techniques to Advanced Memory Devices

ISTFA 1997: Conference Proceedings from the 23rd International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa1997p0063 ◽

1997 ◽

Author(s):

S.-S. Lee ◽

J.-S. Seo ◽

N.-S. Cho ◽

S. Daniel

Keyword(s):

Thermal Emission ◽

Test Cases ◽

Memory Devices ◽

Front Side ◽

Emission Analysis ◽

Intensity Attenuation ◽

Analysis Techniques ◽

Defect Sites ◽

Emission Microscopy ◽

Microscopy Techniques

Abstract Both photo- and thermal emission analysis techniques are used from the backside of the die colocate defect sites. The technique is important in that process and package technologies have made front-side analysis difficult or impossible. Several test cases are documented. Intensity attenuation through the bulk of the silicon does not compromise the usefulness of the technique in most cases.

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