자료유형  

 학위논문

Control Number  

0017162640

International Standard Book Number  

9798384049609

Dewey Decimal Classification Number  

530

Main Entry-Personal Name  

Angel, Jay Scott.

Publication, Distribution, etc. (Imprint  

[S.l.] : Cornell University., 2024

Publication, Distribution, etc. (Imprint  

Ann Arbor : ProQuest Dissertations & Theses, 2024

Physical Description  

227 p.

General Note  

Source: Dissertations Abstracts International, Volume: 86-03, Section: B.

General Note  

Advisor: Hammer, David.

Dissertation Note  

Thesis (Ph.D.)--Cornell University, 2024.

Summary, Etc.  

요약An imploding gas puff z-pinch is the magnetic compression of a cylindrical plasma along the central axis. This implosion occurs when an axial current parallel to the z-axis creates a magnetic field outside the cylinder. As the magnetic pressure increases the cylinder compresses radially, ideally forming the z-pinch along the axis.The density and temperature at pinch time can be very high and for this reason some private companies are exploring z-pinches to produce fusion energy. The magnetic field profile responsible for the z-pinch is inherently dependent on the distribution of the current within the plasma. Currently, probes used to measure the magnetic field distribution, and from that the current distribution, are easily destroyed by the high energy density plasma (HEDP) produced in the process. Therefore it would be beneficial to develop a spectroscopic means to measure the magnetic field as the z-pinch develops.A magnetic field (B-field) splits atomic energy levels, causing spectral lines to split. The B-field magnitude determines the splitting and therefore, by measuring the spectrum, one can determine the B-field. The Stark (electric field) broadening of spectral lines is substantial in dense plasma, with multi-nm width, and for typical fields of 5 T, the Zeeman splitting, as measured by the Zeeman Polarization Spectroscopic (ZPS) system, is only fractions of a nm. In order to resolve the Zeeman splitting it is essential to separate the blue-shifted and red-shifted peaks. Luckily the Zeeman-split line components emitted parallel to the B-field are in two oppositely circularly polarized groups. The two peaks are resolvable if we separate by polarization even with Stark broadening. This "polarization spectroscopy" method was developed, for HEDP gas puff z-pinch situations, at the Weizmann Institute of Science (a Cornell Center collaborator) by Yitzhak Maron et al to be used on Cornell's pulsed power machine COBRA.Experimental results show that the magnetic field measured using the ZPS system confirms that during the implosion phase of the z-pinch all of the machine current is flowing within the radial plasma region known as the magnetic piston, which drives the implosion towards the axis.By examining multiple shots, a current distribution is calculated and the entirety of the machine current is found to be flowing within about 1 mm radially inwards from the piston. This is the first time the current distribution of the imploding gas puff z-pinch has been measured on a 1 MA peak current pulsed power machine.

Subject Added Entry-Topical Term  

Plasma physics.

Subject Added Entry-Topical Term  

High temperature physics.

Subject Added Entry-Topical Term  

Physics.

Index Term-Uncontrolled  

Zeeman Polarization Spectroscopic system

Index Term-Uncontrolled  

Electric field

Index Term-Uncontrolled  

Cylindrical plasma

Index Term-Uncontrolled  

Magnetic field

Added Entry-Corporate Name  

Cornell University Electrical and Computer Engineering

Host Item Entry  

Dissertations Abstracts International. 86-03B.

Electronic Location and Access  

로그인을 한후 보실 수 있는 자료입니다.

Control Number  

joongbu:658249