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Large-scale foundation models (e.g., CLIP) have shown promising zero-shot generalization performance on downstream tasks by leveraging carefully designed language prompts. However, despite their success, most prompt learning techniques tend to underperform in the presence of domain shift. Our study addresses this problem and, to improve CLIP's generalization ability across domains, proposes \textsc{StyLIP}, a novel approach for Domain Generalization (DG) based on a domain-agnostic prompt learning strategy. In the absence of explicit domain knowledge, we aim to disentangle the visual style and the content information extracted from the pre-trained CLIP in the prompts so they can be effortlessly adapted to novel domains during inference. Furthermore, we consider a set of style projectors to learn the prompt tokens directly from these multi-scale style features, and the generated prompt embeddings are later fused with the multi-scale visual features learned through a content projector. The projectors are contrastively trained, given CLIP's frozen vision and text encoders. We present extensive experiments in five different DG settings on multiple benchmarks, demonstrating that \textsc{StyLIP} consistently outperforms the relevant state-of-the-art methods., Comment: 23 pages, 7 figures, 9 tables

Accretion of matter onto the supermassive black holes that live at the heart of most galaxies is one of the most energetic processes in the Universe. These active galactic nuclei (AGN), and the energy they expel, are believed to play a critical role in how galaxies evolve. Despite this, our understanding of how the energy emitted from the active nucleus couples to the rest of the galaxy is limited. The goal of the Close AGN Reference Survey (CARS) has been to construct a dataset that is tailored to answering this question. We have observed the brightest unobscured AGN at redshifts 0.01 < z < 0.06 with the best astronomical observatories in the world, including the Multi Unit Spectroscopic Explorer (MUSE) at ESO’s Very Large Telescope, the Atacama Large Millimeter/submillimeter Array (ALMA), the Very Large Array (VLA), the Hubble Space Telescope, and the Chandra X-ray Observatory. In this article we highlight the ongoing work of the CARS team, along with the recent data release and accompanying papers, before discussing what comes next for the survey., Published in The Messenger vol. 187, pp. 3-7, June 2022.

The energetic feedback generated by the radiation pressure of the accretion disk or the radio jets in active galactic nuclei (AGNs) has been suggested to be able to produce fast ionized outflows, which can be studied using highly ionized emission lines. Radiation pressure from the accretion disk is thought to be the dominant driving mechanism in radio quiet AGN. However, detection of HI absorbing gas in outflow in Low Excitation Radio Galaxies (LERGs) as well as a correlation between [OIII] line width and radio power suggest that the radio jet in radio loud AGN may be capable of driving an outflow. We obtained SDSS spectroscopic data for 18 optically selected LERGs at 0.01< z

The broad line wings in the optical [OIII] 5007 emission line are one of the best signatures of fast ionized gas outflows on host galaxy scales in AGN. While large spectroscopic surveys like SDSS have characterized the kinematics of [OIII] for large samples of AGN in detail, they cannot determine the location and energetics of those outflows. As part of the Close AGN Reference Survey (CARS) we obtained spatially-resolved IFU spectroscopy for a representative sample of 40 luminous type 1 AGN at 0.0195% of the flux associated with a point-like source. Strickingly, we measure small offsets in their spatial location on the order of 100 parsecs from the AGN nucleus using the spectroastrometry technique. Our findings confirm that most of the ionized gas outflows are rather compact and not (yet) reaching significantly into their host galaxy which is in agreement with HST or recent AO observations, but strongly disagrees with several previous IFU studies. Such systematic analyses provided by CARS are therefore the key to establishing a picture of AGN-driven outflows in the local Universe and provide a benchmark for comparison with higher redshift observations of even more powerful AGN.

The broad line wings in the optical [OIII] 5007 emission line are one of the best signatures of fast ionized gas outflows on host galaxy scales in AGN. While large spectroscopic surveys like SDSS have characterized the kinematics of [OIII] for large samples of AGN in detail, they cannot determine the location and energetics of those outflows. As part of the Close AGN Reference Survey (CARS) we obtained spatially-resolved IFU spectroscopy for a representative sample of 40 luminous type 1 AGN at 0.0195% of the flux associated with a point-like source. Strickingly, we measure small offsets in their spatial location on the order of 100 parsecs from the AGN nucleus using the spectroastrometry technique. Our findings confirm that most of the ionized gas outflows are rather compact and not (yet) reaching significantly into their host galaxy which is in agreement with HST or recent AO observations, but strongly disagrees with several previous IFU studies. Such systematic analyses provided by CARS are therefore the key to establishing a picture of AGN-driven outflows in the local Universe and provide a benchmark for comparison with higher redshift observations of even more powerful AGN.

What is a Gravitational Wave? It is the ripples in the curvature of spacetime propagating as waves. It has not been detected for a long time since its strain amplitude is extremely low and the detectors were not sensitive enough. Thanks to LIGO that their detectors have been sensitive enough to detect it. Here, a matched filtering analysis have been performed to investigate the truth about the detection, where the strain data from the two interferometers have been whitened and filtered using bandpass and notch filter. It ultimately gets matched with the NR template very well. A good way to search for a gravitational wave is performing a blind burst search where the signal. Here, the the signal has shown some properties which also has confirmed the detection of gravitational wave as well. There are three phases for the event-inspiral, merger, ringdown among which the merger and the ringdown is still not clear. When their relativistic motion begins only one approach can successfully explain the whole scenario’Effective One Body’ formalism. Here it explains a lot about the last stages of inspiral and the merger. To understand the ringdown phase an easy but effective way is to comapre it with a similar looking signal model. The dominant QNM ringdown frequency is the frequency of the least damped part. It has been determined with the frequency equation of ringdown phase and the analytical value gets very well matched with the observed wave. In the low frequency domain (≈ 1 Hz) classical mechanics holds good . So, applying simple physics for compact binaries it is possible to predict the existence of gravitational wave in that domain.