Maciek Wielgus (Instituto de Astrofisica de Andalucia, Granada, Spain)
Very long baseline interferometry (VLBI) offers a way to study AGN jets with an exceptionally high angular resolution, zooming into the zone of the jet collimation and acceleration. In particular, a global array of the Event Horizon Telescope (EHT) offers unprecedented resolution with highest VLBI observing frequency of 230 GHz. During the first observing campaign of the EHT in 2017, observations of 16 AGN sources were carried out. Together with the previous measurements at lower radio frequencies, these new observations allow for a statistical study of the properties of AGN cores across the angular scales. We observe a persistent and statistically significant effect of brightness temperature increase with the distance from the central black hole, which indicates evolution of Doppler factors in accelerating jets and a gradual conversion of the magnetic energy into kinetic energy. I will describe these observations and discuss what they teach us about the AGN jets.
Sudhagar Suyamprakasam (CAMK, Warsaw)
he LIGO/Virgo/KAGRA (LVK) collaboration has discovered several dozen binary mergers since 2015; however, binary mergers are not the exclusive sources of gravitational waves. Asymmetric rotating neutron stars and planetary or asteroid mass-primordial BH (PBH) binaries during their in-spiral phase also emit quasi-monochromatic, long-duration gravitational waves. Detecting signals from these sources requires longer observation times due to their weak amplitude with respect to the current sensitivity of detectors, and thus far, the detection of those signals has not been confirmed yet. Suppose the massive object lies in the line of sight; the signal can undergo gravitational lensing. This presentation provides a brief overview of gravitational wave gravitational lensing, an emerging subdomain in gravitational wave astronomy, and the impact of the gravitational lensing signature in long-duration signals, which provides new possibilities for detecting the signals from those sources.
Luke Dones (Southwest Research Institute, Boulder, Colorado)
Jarosław Duda (Jagiellonian University, Cracow)
While naively laser only excites target, it can also cause its deexcitation – as stimulated emission, SASE (self-amplified spontaneous emission), synchrotron self-absorption, ASE (amplified spontaneous emission), or in Rabi cycle cyclically causing excitation and deexcitation. STED microscopy is a popular application of laser causing deexcitation - I would like to propose and discuss a few more, based on its properties suggested by CPT symmetry. For example, while CT scanner makes 3D maps of absorption coefficient, CPT symmetry suggests how to analogously measure/map emission coefficients, what should have much better transparency thanks to lower concentrations (N2 << N1). Related medical application could be causing deexcitation of autoluminescent molecules like NADH, e.g. to starve cancer tissue. It suggests also how to build new type of telescope - seeing synchrotron radiation, but not thermal. Finally, the original motivation was more symmetric and powerful two-way quantum computers (2WQC), for example with photonic chip between coupled laser resonators.
Surajit Kalita (Warsaw University Observatory)
