Modeling non-thermal emission from SN 1987A

AbstractAn asymmetry of optical emission lines that appeared in Sept. 1988 is interpreted as evidence of dust condensation within the metal-rich ejecta of SN 1987A. A quantitative analysis of this spectroscopic effect is given and shown to be compatible with the photometric record. Moreover, observational and theoretical estimates of the bolometric light curve come into agreement when the far-IR excess is interpreted as thermal emission by grains in the ejecta. A grain population comprising small silicate grains with an admixture of graphite or amorphous carbon particles is suggested by the data. The relevance of this discovery to suggestions that supernovae are major sources of interstellar dust is briefly discussed.

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Thermal X-Rays due to Ejecta/CSM Interaction in SN 1987A

International Astronomical Union Colloquium ◽

10.1017/s0252921100094379 ◽

1988 ◽

Vol 108 ◽

pp. 450-451

Author(s):

K. Masai ◽

S. Hayakawa ◽

H. Itoh ◽

K. Nomoto ◽

T. Shigeyama

Keyword(s):

Light Curve ◽

Photon Energy ◽

Thermal Emission ◽

Circumstellar Matter ◽

Expansion Velocity ◽

X Rays ◽

X Ray ◽

Sn 1987A ◽

Inner Radius

The X-ray spectrum observed by Ginga is characterized by a component below 10keV which decreases with increasing photon energy, and a component above 10keV which is nearly flat. This unusual X-ray spectrum may be understood as follows; X-rays below 10keV is likely to be due to thermal emission coming from the shock-heated ejecta, and X-rays above 10keV to be due to γ-ray degradation inside the ejecta. If thermal emission due to the collision of the ejecta with circumstellar matter (CSM) is responsible for X-rays below 10keV, the epoch of the collision can be estimated to be ∼ 0.2yr after the explosion if ∼ 0.5yr is the time when the X-ray flux at ∼ 10keV reaches its maximum. The X-ray light curve then requires the inner radius of CSM to be ∼ 1×1016cm for an expansion velocity, Vex ≃2×109cm s−1.

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Freeze out, IR-catastrophes and Non-thermal Emission in SNe

International Astronomical Union Colloquium ◽

10.1017/s0252921100008083 ◽

1996 ◽

Vol 145 ◽

pp. 211-222 ◽

Cited By ~ 1

Author(s):

Claes Fransson ◽

John Houck ◽

Cecilia Kozma

Keyword(s):

Light Curve ◽

Total Mass ◽

Thermal Emission ◽

Sharp Decrease ◽

Light Curves ◽

Thermal Excitation ◽

Sn 1987A ◽

Ubv Photometry ◽

Optical Flux ◽

Freeze Out

Freeze out effects and the IR-catastrophe are discussed for SN 1987A and for Type la SNe. We show that the light curves of the optical lines in SN 1987A provide strong evidence for the IR-catastrophe. We also argue that most optical lines are dominated by non-thermal excitation after ∼ 800 days. The level of this emission is set mainly by the total mass of the elements. Models of the [OI]λλ6300 — 64 light curve show that an oxygen mass of ∼ 1.5Mʘ is needed. Light curve models for Type la SNe display a sharp decrease in the optical flux as a result of the IR-catastrophe at ∼ 500 days, producing UBV-photometry inconsistent with observations of SN1972E by Kirshner & Oke (1975).

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Distance to SN 1987A and the LMC

Symposium - International Astronomical Union ◽

10.1017/s0074180900118959 ◽

1999 ◽

Vol 190 ◽

pp. 549-554

Author(s):

Nino Panagia

Keyword(s):

Angular Size ◽

Large Magellanic Cloud ◽

Magellanic Cloud ◽

Light Curves ◽

Distance Modulus ◽

Absolute Size ◽

Sn 1987A

Using the new reductions of the IUE light curves by Sonneborn et al. (1997) and an extensive set of HST images of SN 1987A we have repeated and improved Panagia et al. (1991) analysis to obtain a better determination of the distance to the supernova. In this way we have derived an absolute size of the ringRabs= (6.23 ± 0.08) x 1017cm and an angular sizeR″ = 808 ± 17 mas, which give a distance to the supernovad(SN1987A) = 51.4 ± 1.2 kpc and a distance modulusm–M(SN1987A) = 18.55 ± 0.05. Allowing for a displacement of SN 1987A position relative to the LMC center, the distance to the barycenter of the Large Magellanic Cloud is also estimated to bed(LMC) = 52.0±1.3 kpc, which corresponds to a distance modulus ofm–M(LMC) = 18.58±0.05.

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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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Nuclear γ ray lines in the supernova SN 1987a

Annales de Physique ◽

10.1051/anphys:01991001604044300 ◽

1991 ◽

Vol 16 (4) ◽

pp. 443-457

Author(s):

R. Lehoucq ◽

Ph. Durouchouxa

Keyword(s):

Sn 1987A ◽

Γ Ray

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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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