Particle Physics on the Plains​ 2023

Session

Gravitational Waves and Astroparticle Physics

15 Oct 2023, 08:55

2048 Malott Hall (University of Kansas)

Conveners

Gravitational Waves and Astroparticle Physics

• Peisi Huang

13. Did we hear the sound of the Universe boiling? Analysis using the full fluid velocity profiles and NANOGrav 15-year data

Dr Fazlollah Hajkarim (University of Oklahoma)

15/10/2023, 08:55

We analyse sound waves arising from a cosmic phase transition where the full velocity profile is taken into account as an explanation for the gravitational wave spectrum observed by multiple pulsar timing array experiments. Unlike the broken power law used in the literature, in this scenario the power law after the peak depends on the macroscopic properties of the phase transition, allowing...

19. Probing Exotic Phases Via Stochastic Gravitational Wave Spectra

Mr Biswajit Padhi (Colorado State University)

15/10/2023, 09:13

Stochastic backgrounds of gravitational waves (GWs) from the pre-BBN era offer a unique opportunity to probe the universe beyond what has already been achieved with the Cosmic Microwave Background (CMB). If the source is short in duration, the low-frequency tail of the resulting GW spectrum follows a universal frequency scaling dependent on the equation of state of the universe when modes...

29. First Order Electroweak Phase Transitions in the SM with a Real Scalar Singlet Extension

Anthony Hooper

15/10/2023, 09:31

We investigate an extension of the standard model (SM) with a real scalar singlet without $\mathbb{Z}_2$ symmetry, requiring a first order electroweak phase transition (FOPT) to occur to satisfy the condition for electroweak baryogenesis. We perform numerical calculations that include one-loop thermal effects and Coleman-Weinberg corrections with daisy resummation. The bubble nucleation...

10. Dark Mediator Spectroscopy with Binary Inspirals.

Badal Bhalla (University of Oklahoma)

15/10/2023, 09:49

Binary inspirals can serve as probes of dark mediators, under the assumption that the spiraling objects are charged under a new long-range dark force. The range of mediator masses probed by the inspirals of astrophysical bodies spans O(10^-14)eV–O(10^-22)eV. The sensitivity of the spectroscopy in all cases depends on the strength of the dark coupling and the amount of dark charge. We calculate...

14. Hawking Radiation, Superradiance, and Dark Sector

Tao Xu (The University of Oklahoma)

15/10/2023, 10:07

Gravitational particle production from black holes offers a novel avenue for exploring particle physics, particularly in the case of dark sector particles whose non-gravitational interactions remain beyond the reach of conventional laboratory searches. In this talk, I will discuss two production mechanisms: Hawking radiation and Superradiance. Via Hawking radiation, black holes can generate...

20. A New Probe of Relic Neutrino Clustering Using Decaying Heavy Dark Matter

Ms Writasree Maitra

15/10/2023, 10:25

The existence of relic neutrino background is a strong prediction of big bang cosmology. But because of their extremely small kinetic energy today, the direct detection of relic neutrinos remains elusive. On the other hand, we know very little about the nature of dark matter. In this work, we show that heavy dark matter (with mass in the range of $10^9$ to $10^{15}$ GeV) decaying into...

7. Impact of non-standard neutrino self interactions on sterile neutrino dark matter production in the early universe

Aaroodd UR

15/10/2023, 10:43

Active-sterile mixing is the simplest mechanism to produce sterile neutrinos in the
early Universe. However, the generic production mechanism, known as the Dodelson-Widrow mechanism, is in tension with the astrophysical bounds coming from structure
formation and X-ray observations. Thus, it is necessary to introduce new interactions
to modify the DW production, as this mechanism is...