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Optical Readout Time Projection Chamber (O-TPC) for a Study of Oxygen Formation In Stellar Helium Burning

Moshe Gai·Amos Breskin·Rachel Chechik·Volker Dangendorf·Henry R. Weller
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Abstract

We are developing an Optical Readout Time Projection Chamber (O-TPC) detector for the study of the 12C(a,g)16O reaction that determines the ratio of carbon to oxygen in helium burning. This ratio is crucial for understanding the final fate of a progenitor star and the nucleosynthesis of elements prior to a Type II supernova; an oxygen rich star is predicted to collapse to a black hole, and a carbon rich star to a neutron star. Type Ia supernovae (SNeIa) are used as standard candles for measuring cosmological distances with the use of an empirical light curve-luminosity stretching factor. It is essential to understand helium burning that yields the carbon/oxygen white dwarf and thus the initial stage of SNeIa. The O-TPC is intended for use with high intensity photon beams extracted from the HIgS/TUNL facility at Duke University to study the 16O(g,a)12C reaction, and thus the direct reaction at energies as low as 0.7 MeV. We are conducting a systematical study of the best oxygen containing gas with light emitting admixture(s) for use in such an O-TPC. Preliminary results with CO_2 + TEA mixture were obtained

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Moshe Gai, Amos Breskin, Rachel Chechik, Volker Dangendorf, Henry R. Weller. 2005-04-01. Optical Readout Time Projection Chamber (O-TPC) for a Study of Oxygen Formation In Stellar Helium Burning. https://doi.org/10.1556/aph.25.2006.2-4.37

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