Speaker: Zhengkang Zhang
Host:
Title: Effective Field Theory of Dark Matter Direct Detection With Collective Excitations
Zoom: https://zoom.us/j/186024391
Abstract:
I will present a framework for computing dark matter direct detection rates via phonon and magnon excitations in crystal targets for general dark matter models. It consists of parameterizing dark matter interactions by a nonrelativistic EFT, and computing material responses to the EFT operators. Our work extends previous calculations that focused on simple models such as standard spin-independent interactions, and shows that new direct detection experiments that utilize collective excitations, such as SPICE, will have discovery potential over a broad range of dark matter theories.
Description:
Groundhog Day
User:
High-Energy Seminars
Time:
1:30pm - 2:30pm
Send Reminder:
Yes - 0 days 8 hour 0 minutes before start
Description:
Speaker: Ben Safdi
Title: Listening for Axion Dark Matter with Radio Telescopes
Abstract: Abstract: The quantum chromodynamics axion is a well-motivated dark matter candidate that may also solve the strong CP problem related to the absence of the neutron electric dipole moment. Multiple experimental efforts are currently racing to try to discover this particle in the laboratory. In this talk I will show that astrophysical observations are also a promising path towards detecting the axion. In particular, I will demonstrate that axion dark matter may convert to narrow radio lines in the strong magnetic fields surrounding neutron stars. I will present first results from a dedicated radio search performed with data from the Green Bank and Effelsberg radio telescopes, and I will discuss future detection prospects.
Host: Markus Luty
Zoom: https://zoom.us/j/186024391
Host: Markus Luty
Description:
Valentine's Day
Description:
Presidents' Day
User:
High-Energy Seminars
Time:
1:30pm - 2:30pm
Send Reminder:
Yes - 0 days 8 hour 0 minutes before start
Description:
Speaker: Anson Hook
Title: Aharonov-Bohm in the Sky : A CMB Millikan Experiment with Cosmic Axiverse Strings
Zoom: https://zoom.us/j/186024391
Host: Markus Luty
Abstract: We show that photons moving around an axion string coupled to photons undergo an Aharonov-Bohm effect. As a result, axion strings produce a distinct quantized polarization rotation of CMB photons which can be as large as O(1%). As the CMB passes many strings, this polarization rotation converts E-modes to B-modes and adds up like a random walk. We show that the expected size of the final result is well within the reach of current and future CMB experiments. The quantized polarization rotation angle is topological in nature and its value provides insight into the quantization of electric charge.
