BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:A Redshift-Limited Sample Selection and Photometric Redshift Estim ation for 4MOST WAVES: Prospects for LSST DTSTART;VALUE=DATE-TIME:20261020T125000Z DTEND;VALUE=DATE-TIME:20261020T130500Z DTSTAMP;VALUE=DATE-TIME:20261112T103434Z UID:indico-contribution-438-2265@events.ncbj.gov.pl DESCRIPTION:Speakers: Gursharanjit Kaur (Center for Theoretical Physics\, PAN)\nIn this talk\, I will present a machine learning-based approach to s elect a redshift-limited sample using multiband photometry when spectrosco pic redshifts are not available. The technique is a decision tree-based bi nary classification\, which has been further extended into a photometric r edshift estimation method. This selection methodology has been applied to select targets for the WAVES survey of the Multi-Object Spectroscopy Facil ity (4MOST). WAVES has a key science goal of probing the halo mass functio n to fainter magnitudes compared to previous surveys like GAMA. The ML sel ection method achieves completeness of over 90%\, as desired by the survey . We demonstrate that our method achieves photo-z scatter σ_NMAD ~ 0.015 when tested against the DESI DR1 sample flux-limited to 21.2 in Z-band mag nitude. \n\nThis sample selection and photometric redshift estimation meth odology can be successfully applied to a large photometric survey like LSS T\, and we see it as a potential contribution to the LSST DESC photo-z com munity.\n\nhttps://events.ncbj.gov.pl/event/502/contributions/2265/ LOCATION: URL:https://events.ncbj.gov.pl/event/502/contributions/2265/ END:VEVENT BEGIN:VEVENT SUMMARY:Unlocking Non-linear Pairwise Velocities in the LSST Era DTSTART;VALUE=DATE-TIME:20261020T123500Z DTEND;VALUE=DATE-TIME:20261020T125000Z DTSTAMP;VALUE=DATE-TIME:20261112T103434Z UID:indico-contribution-438-2264@events.ncbj.gov.pl DESCRIPTION:Speakers: Mariana Jaber (NCBJ)\nPeculiar velocities provide a complementary probe of large-scale structure by directly tracing the gravi tational dynamics of structure formation. Yet observational analyses of pa irwise velocities and the pairwise kinetic Sunyaev-Zel’dovich signal rem ain largely restricted to linear and quasi-linear scales\, leaving substan tial cosmological information at smaller separations untapped.\n\nWe prese nt a simulation-calibrated likelihood for the mean pairwise velocity\, v12 (r\,a)\, based on the exact pair conservation equation and non-linear matt er clustering\, validated against the Quijote and TNG300-3 simulations. Ex tending the analysis from a linear-regime baseline of 50 Mpc/h down to 4 M pc/h at z=0.5 reduces the uncertainty on fσ8 by up to 86%\, while the joi nt Ωm–fσ8 Figure-of-Merit improves by up to a factor of 9.1.\n\nThese gains motivate asking how much of this non-linear information can be recov ered with LSST-era datasets. LSST will provide dense photometric samples f or cross-correlation with spectroscopic and CMB surveys\, while photometri c redshift uncertainties\, tracer selection and galaxy velocity bias compl icate the interpretation of small-scale pairs. Our framework provides a co ntrolled starting point for quantifying these effects and determining the scales on which non-linear pairwise motions can become a practical cosmolo gical probe.\n\nhttps://events.ncbj.gov.pl/event/502/contributions/2264/ LOCATION: URL:https://events.ncbj.gov.pl/event/502/contributions/2264/ END:VEVENT BEGIN:VEVENT SUMMARY:Improved delensing of CMB B-modes with upcoming SO and LSST Year-1 data DTSTART;VALUE=DATE-TIME:20261020T121500Z DTEND;VALUE=DATE-TIME:20261020T123500Z DTSTAMP;VALUE=DATE-TIME:20261112T103434Z UID:indico-contribution-438-2263@events.ncbj.gov.pl DESCRIPTION:Speakers: Kishan Deka (NCBJ (BP4))\nIn the era of high-precisi on Cosmic Microwave Background (CMB) anisotropy measurements\, detection o f primordial gravitational waves (PGWs) is one of the main goals of curren t CMB experiments. Detection of a divergence-free (B-mode) component in CM B polarisation will provide direct evidence of inflationary PGWs in the ea rly universe. However\, weak gravitational lensing of CMB photons due to i ntervening mass distribution of the Universe distorts the primordial polar isation patterns\, introducing an additional lensing-induced B-mode signal . Removing these lensing-induced B-modes is essential for improving constr aints on the amplitude of PGWs. In this work\, we test a tomographic delen sing method on simulations of the Rubin Observatory LSST galaxy catalogue and Simons Observatory (SO) CMB maps. A significant improvement in delensi ng efficiency is achieved by using a multi-tracer approach\,\nwhere we spl it the galaxy dataset into tomographic redshift bins. However\, uncertaint ies in photometric redshift measurements pose a problem for optimal weight ing of the tracers. In this work\, we set up a pipeline to perform a multi -tracer delensing method and studied the impact of photometric redshift er rors\, using realistic simulations of LSST galaxy catalogue and SO CMB map s.\n\nhttps://events.ncbj.gov.pl/event/502/contributions/2263/ LOCATION: URL:https://events.ncbj.gov.pl/event/502/contributions/2263/ END:VEVENT BEGIN:VEVENT SUMMARY:Cosmology with quasars in Kilo-Degree Survey DTSTART;VALUE=DATE-TIME:20261020T130500Z DTEND;VALUE=DATE-TIME:20261020T132000Z DTSTAMP;VALUE=DATE-TIME:20261112T103434Z UID:indico-contribution-438-2266@events.ncbj.gov.pl DESCRIPTION:Speakers: Szymon Nakoneczny (CFT PAN)\nI will present my curre nt work on cosmological inference with quasars (QSOs) from the Kilo-Degree Survey (KiDS). In both the classification and the photometric redshift (p hoto-z) steps\, I test how far the models can be extrapolated beyond the c overage of the spectroscopic training data\, and how the resulting errors propagate into the cosmological constraints. I compare ML methods for unce rtainty estimation in QSO photo-z\, and describe the calibration of the cl assification and photo-z results with self-organising maps (SOMs). Finally \, I present preliminary constraints from the KiDS QSO samples\, obtained with tomographic binning in photo-z. Both the methods and the results carr y over directly to LSST\, which will deliver quasar samples that are large r and deeper\, but even less well covered by spectroscopic training data.\ n\nhttps://events.ncbj.gov.pl/event/502/contributions/2266/ LOCATION: URL:https://events.ncbj.gov.pl/event/502/contributions/2266/ END:VEVENT END:VCALENDAR