KIPAC Tea Talk: Uncovering Collisionally Ionized, Relativistic, and BAL-like Outflows in MCG-6-30-15 with Chandra HETG, XRISM, and Bayesian Framework / Turning a Dark Matter Detector into a Neutrino Observatory: Latest Results from XENONnT

Hoffman Abstract: Highly ionized winds are a promising candidate for Active Galactic Nuclei (AGN) feedback. Precisely constraining these winds requires careful analysis of absorption lines in high-resolution X-ray spectra from nearby AGN, for which typical studies are not yet optimized. New approaches to analyzing data from Chandra's High Energy Transmission Grating (HETG) and XRISM Resolve can yield crucial progress. In this poster, I will present results for a Bayesian analysis framework on deep, archival HETG MCG-6-30-15 2000 & 2004 data. We uncover a hot relativistic ultra-fast outflow (UFO) previously undetected in HETG, independently observed in XRISM, and tentative cool UFOs. We reveal a more slow warm absorbers and detect the first potential collisional absorbers in this system. Finally, we uniformly trace how these winds evolved over 25 years, the longest possible timeline using XRISM, and emphasize the arrival of a new era in high spectral resolution X-ray astrophysics.

Xu Abstract: XENONnT is a dual-phase time projection chamber with a 5.9-tonne liquid xenon target, operating underground at the Laboratori Nazionali del Gran Sasso. Originally designed for weakly interacting massive particle (WIMP) searches, its exceptionally low background and low energy threshold have opened new opportunities for solar neutrino physics.I will present two recent XENONnT measurements that exploit the complementary electronic and nuclear recoil channels. In the electronic recoil channel, I will discuss the signal and background modeling behind a 5.0 sigma measurement of elastic neutrino-electron scattering (ES) with a 2.5 tonne-year exposure, detecting solar neutrinos with energies down to 17 keV, the lowest neutrino energy threshold achieved to date. In the nuclear recoil channel, dedicated reconstruction and selection strategies suppress accidental-coincidence backgrounds by more than a factor of 1000, enabling a 3.3 sigma measurement of coherent elastic neutrino-nucleus scattering (CEvNS) from solar Boron-8 neutrinos with a 6.8 tonne-year exposure. I will describe these techniques, along with the low-energy calibration and detector response model underlying the analysis. I will conclude with prospects for next-generation multipurpose liquid xenon observatories to enable precision tests of electroweak and neutrino physics.