Kavli Affiliate: Martin Haehnelt | Summary:The Genesis Initiative is an extragalactic community-wide effort to coordinate white papers in response to the STScI Multi-Cycle Treasury (MCT) concept call. Two of JWST’s primary science goals are to discover and characterize the first stars and galaxies, and to understand how they evolved into the galaxies we see today […]
Kavli Affiliate: Martin Haehnelt | Summary:JWST has revealed an abundant population of faint active galactic nuclei and a new class of compact, high-redshift sources known as Little Red Dots (LRDs), whose physical nature remains debated, with accreting massive black holes among the leading explanations. The emerging demographics of early black holes, with their high inferred […]
Kavli Affiliate: Roberto Maiolino | Summary:The origin of anomalous chemical enrichment in high-redshift galaxies discovered by JWST remains a key question in galaxy evolution. Enhanced nitrogen abundances have been identified in several galaxies at early cosmic times, but the physical conditions driving this enrichment, and their connection to galaxy morphology, remain unclear. We test whether […]
Kavli Affiliate: Roberto Maiolino | Summary:JWST has extended the search for accreting black holes into the high-redshift, low-mass regime. We report a low-mass black hole candidate in MARTA 3887, a clumpy, metal-poor galaxy at $z=3.7694$, combining deep JWST/NIRSpec spectroscopy, HST and JWST imaging, and archival VLT/MUSE data. We detect a broad H$α$ component with $L_rm […]
Kavli Affiliate: Anthony Challinor | Summary:The thermal Sunyaev–Zel’dovich (tSZ) field is highly non-Gaussian and contains cosmological information that cannot be fully captured by its angular power spectrum. In this work, we investigate the information content of this field using a convolutional neural network (CNN), and compare to simple and interpretable summary statistics, in a simulation-based […]
Kavli Affiliate: Debora Sijacki | Summary:The circumgalactic medium (CGM) of massive high-redshift galaxies contains inflowing filamentary gas, recycled material, and feedback-driven outflows. We investigate the formation and evolution of dense CGM clumps in two cosmological zoom-in simulations of the same massive halo at $z > 6$: the fiducial Fable model and the modified Fable-SE model, […]
Kavli Affiliate: Roberto Maiolino | Summary:JWST surveys find more UV-bright galaxies at $z>10$ than galaxy-formation models predict, but the roles of recent star formation, stellar mass and dust remain uncertain. We analyse 1365 spectroscopically confirmed JADES galaxies at $3leq zleq9$, fitting NIRCam photometry and NIRSpec emission lines with ceri. Our model includes flexible star-formation histories […]
Kavli Affiliate: Kaisey Mandel | Summary:Photometric Type Ia supernova (SN Ia) cosmology in the era of the Vera C. Rubin Observatory’s Legacy Survey of Space and Time (LSST) demands statistical frameworks that simultaneously account for selection effects, photometric redshift uncertainties and non-Ia contamination at scale. We present FlowSN2, a modular statistical framework combining hierarchical Bayesian […]
Kavli Affiliate: Blake Sherwin | Summary:The recent measurement of baryon acoustic oscillations by the Dark Energy Spectroscopic Instrument reveals a mild tension with observations of the cosmic microwave background (CMB) within the standard $Λ$CDM cosmological model. Another interesting hint beyond standard cosmology arises from recent analyses of Planck polarization data which has been interpreted as […]
Kavli Affiliate: Roberto Maiolino | Summary:We measure the fraction of clumpy galaxies ($f_rm clumpy$) over the redshift range $z=1-9$ and stellar masses $log_10(M_star/rm M_odot) geq 8$ using JWST/NIRCam imaging from JADES. We define clumps as compact off-centre surface-brightness peaks with characteristic sizes of a few hundred parsecs, and develop a dendrogram-based clump-finding method with astrodendro […]