Shifa Bashir

Measuring the Effect of a Change in Neutrino Chemical Potential on the Primordial Value of Helium-4 and Deuterium

Started Sept. 24, 2024

Abstract or project description

The essential nature of this research is to alter a section of primordial code, PRyMordial, to observe the effect on the abundances of light elements, specifically of helium-4 and deuterium. By altering the code, we can discover a range of values of neutrino chemical potential (NCP) that can relieve the tension between the observed and theoretical abundances. My partner and I hypothesized that the values of the NCP would be relatively close to zero, suggesting that there is minimal asymmetry between neutrinos and antineutrinos. By running PRyMordial several times, the theoretical values were collected and inputted into our code to produce a graph. The graphs have horizontal lines representing the true values for the light elements. The data points are the theoretical values connected by a continuous line. The intersection of this line and the bar of observed abundances are used to reveal the range of values for NCP. We discovered that the values of chemical potential relieving the tension for deuterium are -0.08 to -0.43. For helium-4 the values of chemical potential differ; the range is between -0.005 and 0.02. Since there are two bands of true values from different sources, we have two ranges for helium-4, the second being 0.03 to 0.056. The resulting ranges corroborated our initial hypothesis by confirming that the values were near zero.