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Nucleosynthesis in Supernova Shock Waves

Supernova Science with an Advanced Compton Telescope

Hadronic Gamma Rays from Supernova Remnants

A gas cloud near a supernova remnant (SNR) provides a target for pp-collisions leading to subsequent.

AAVSO Supernova Search Manual

Simulating Supernova Shock Propagation Through Stellar Envelopes in 3D

Gravitational Lensing of Supernova Neutrinos

The black hole at the center of the galaxy is a powerful lens for supernova neutrinos. In the very special circumstance of a supernova near the extended line of sight from Earth to the galactic center
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Simulating Supernova Feedback in Galaxy Disks

Supernova Constraints on a Superlight Gravitino

Ionixation and Heating of the Gum Nebula by Energetic Particles from the Vela X Supernova

Condensation of Carbon in Radioactive Supernova Gas

Overview of the SuperNova

Radio Polarisation Study of the Snail Pulsar Wind Nebula in Supernova Remnant G327.1-1.1

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Nucleosynthesis in Supernova Shock Waves

James W. Truran, William David Arnett, Alastair Graham Walter Cameron,

Supernova Science with an Advanced Compton Telescope

Gamma-ray line emission is a direct probe of the nucleosynthesis that occurs in Type Ia supernovae. In this work we describe the wealth of information obtainable from observations of this emission. Advanced Compton telescope designs are being studied by the Naval Research Laboratory, with the goal being the construction of a telescope which would be capable of detecting SNe Ia to distances in excess of 100 Mpc. We describe the instrument capabilities and the design issues that are being addressed. We assume a SN Ia rate and quantify the frequency at which an advanced Compton telescope could detect, discriminate between, and diagnose Type Ia supernovae. From these estimates, we argue that an advanced Compton telescope would be a powerful astrophysical tool.

Gamma-ray line emission is a direct probe of the nucleosynthesis that occurs in Type Ia supernovae. In this work we describe the wealth of information obtainable from observations of this emission.

Hadronic Gamma Rays from Supernova Remnants

A gas cloud near a supernova remnant (SNR) provides a target for pp-collisions leading to subsequent.

AAVSO Supernova Search Manual

Rev. Robert O. Evans, American Association of Variable Star Observers,

Simulating Supernova Shock Propagation Through Stellar Envelopes in 3D

Nicolay Jan Hammer,

Gravitational Lensing of Supernova Neutrinos

The black hole at the center of the galaxy is a powerful lens for supernova neutrinos.

Simulating Supernova Feedback in Galaxy Disks

Peter Edward Creasey,

Supernova Constraints on a Superlight Gravitino

In supergravity models with low supersymmetry breaking scale the gravitinos can be superlight, with mass in the 10[sup -6] eV to few keV range. In such a case, gravitino emission provides a new cooling mechanism for protoneutron stars and therefore can provide constraints on the mass of a superlight gravitino. This happens because the coupling to matter of superlight gravitinos is dominated by its goldstino component, whose coupling to matter of superlight gravitinos is dominated by its goldstino component, whose coupling to matter is inversely proportional to the scale of supersymmetry breaking and increases as the gravitino mass decreases. Present observations therefore provide lower limits on the gravitino mass. Using the recently revised goldstino couplings, we find that the two dominant processes in supernova cooling are e[sup+] e[sup -][yields] GG and[gamma]+e[sup -][yields] e[sup -] GG. They lead to a lower limit on the supersymmetry breaking scale[Lambda][sub s] from 160 to 500 GeV for core temperatures 30 to 60 MeV and electron chemical potentials 200 to 300 MeV. The corresponding lower limits on the gravitino mass are .6 - 6 x 10[sup -6] eV.

In supergravity models with low supersymmetry breaking scale the gravitinos can be superlight, with mass in the 10[sup -6] eV to few keV range.

Ionixation and Heating of the Gum Nebula by Energetic Particles from the Vela X Supernova

R. Ramaty,

Condensation of Carbon in Radioactive Supernova Gas

Ethan A.-N. Deneault,

Overview of the SuperNova

The SuperNova/Acceleration Probe (SNAP) is a space-based experiment to measure the expansion history of the Universe and study both its dark energy and the dark matter. The experiment is motivated by the startling discovery that the expansion of the Universe is accelerating. A 0.7 square-degree imager comprised of 36 large format fully-depleted n-type CCD's sharing a focal plane with 36 HgCdTe detectors forms the heart of SNAP, allowing discovery and lightcurve measurements simultaneously for many supernovae. The imager and a high-efficiency low-resolution integral field spectrograph are coupled to a 2-m three mirror anastigmat wide-field telescope, which will be placed in a high-earth orbit. The SNAP mission can obtain high-signal-to-noise calibrated light-curves and spectra for over 2000 Type Ia supernovae at redshifts between z = 0.1 and 1.7. The resulting data set can not only determine the amount of dark energy with high precision, but test the nature of the dark energy by examining its equation of state. In particular, dark energy due to a cosmological constant can be differentiated from alternatives such as ''quintessence'', by measuring the dark energy's equation of state to an accuracy of ± 0.05, and by studying its time dependence.

The SuperNova/Acceleration Probe (SNAP) is a space-based experiment to measure the expansion history of the Universe and study both its dark energy and the dark matter.

Radio Polarisation Study of the Snail Pulsar Wind Nebula in Supernova Remnant G327.1-1.1

This dissertation, "Radio Polarisation Study of the Snail Pulsar Wind Nebula in Supernova Remnant G327.1-1.1" by Yik-ki, Ma, 馬奕騏, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Pulsar wind nebulae (PWNe) are believed to be acceleration sites of cosmic rays in the Galaxy. In the acceleration process, magnetic field plays an important role. Radio polarisation measurements offer a direct probe of the magnetic field geometry of astronomical objects, but such experiments have rarely been conducted on PWNe, especially for evolved systems. PWNe can be crushed by the supernova reverse shock at an age of 10 kyr. Previous hydrodynamical simulations show that such interactions can result in a turbulent environment in the nebula interior, suggesting a tangled magnetic field. In this thesis, I present a radio study of the Snail PWN in the composite supernova remnant G327.1-1.1 using the Australia Telescope Compact Array. This PWN is believed to have already interacted with the supernova reverse shock. The study reveals a highly ordered magnetic field configuration in the Snail, which can be explained if either the shockwave could not penetrate into the PWN interior to drive the turbulence, or the characteristic turbulence scale is large. A toy model is built to estimate the turbulence scale assuming the latter scenario. It is found that a simulated PWN with a turbulence scale of one-eighth to one-sixth of the nebula radius and a pulsar wind filling factor of 50-75% can match the observation results. This suggests significant mixing between supernova ejecta and pulsar wind material in this system. In addition, the Snail exhibits a subsonic comet-like protrusion extending from the putative neutron star. Cometary PWNe were found to exhibit a variety of magnetic field configurations but the exact reason remains unclear. The polarisation observations of this system revealed a magnetic field parallel to the nebula elongation, similar to what was found in the Mouse (G359.23-0.82) and the handle of the Frying Pan (G315.78-0.23). This adds an important sample to cometary PWNe for future MHD modelling. Subjects: Supernova remnants Pulsars

Yik-Ki Ma, 馬奕騏,

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