Kavli Affiliate: James Analytis| Summary:The unusual transport properties of strange metals point to the breakdown of the quasiparticle picture, the understanding of which remains one of the most vexing problems in physics. Here, we report investigations of the electrical Hall effect of the strange metal superconductor BaFe$_2$(As$_1-x$P$_x$)$_2$. We show that a doping-independent contribution to the […]
Kavli Affiliate: David Muller | Summary:Oxygen dopants play a critical role in tuning the properties of cuprate superconductors, yet it is challenging to visualize them at the atomic scale. Here, we use multislice electron ptychography to directly image oxygen dopants in a Sr2CuO3+delta film. We observe oxygen dopants at interstitial sites between the Cu-O chains, […]
Kavli Affiliate: Fukun Liu| Summary: About twenty late B-type hypervelocity stars (HVSs) traveling faster than the Galactic escape velocity have been discovered in the Galactic halo, many of which were ejected from the Galactic center (GC). Recently, we have advocated that these HVSs most likely formed in the nuclear star cluster (NSC) $150$–$500, rmMyr$ ago […]
Kavli Affiliate: Menno Veldhorst | Summary:Understanding collective phases of strongly correlated quantum magnets relies on theoretically tractable model systems with precise microscopic control. Antiferromagnetic spin ladders provide such a setting, hosting field-tunable gapped and gapless phases at half filling and unconventional pairing tendencies upon doping. Here, we realize a programmable Heisenberg spin ladder in a […]
Kavli Affiliate: Luis Ho | Summary:We use 50 Sobol-sampled VariableTNG simulations, varying eight subgrid parameters at fixed cosmology and initial conditions, to determine which baryonic processes regulate galaxies and black holes at $z=6$ and $z=8$. We compare the simulations with recent high-redshift measurements of the stellar mass function, star-forming main sequence, stellar and gas-phase mass-metallicity […]
Kavli Affiliate: Katrin Heitmann | Summary:Early Dark Energy (EDE) models have been suggested as a possible solution to the so-called Hubble Tension, a discrepancy of the measurement of the Hubble constant at early and late times. In this paper, we investigate the effects of EDE on large-scale structure probes of cosmology via the EDENS (Early […]
Kavli Affiliate: Paul Schechter | Summary:Finch et al (2002) derived relations for the summed absolute magnifications of quadruply lensed images that vary inversely with flattening in two alternative isothermal gravitational potential models. However, they did not elaborate on the selection effects this "flatter-fainter” relation induces in actual lensed systems. We test the relation against the […]
Kavli Affiliate: Bruce Macintosh | Summary:The upcoming Roman Coronagraph will be the first high-contrast instrument in space capable of high-order wavefront sensing and control technologies, a critical technology demonstration for the proposed Habitable Worlds Observatory (HWO) that aims to directly image and characterize habitable exoEarths. The nominal Roman Coronagraph observing plan involves alternating observations of […]
Kavli Affiliate: Luis Ho | Summary:Understanding the physical processes that regulate galaxy quenching is a key challenge in galaxy formation and evolution. The VariableTNG (VTNG) project provides a laboratory to investigate these processes, as it systematically varies eight parameters of galaxy formation while keeping the initial conditions fixed, allowing the effects of individual feedback prescriptions […]
Kavli Affiliate: Anna Frebel | Summary:We present our chemical abundance analysis of ten new extremely metal-poor stars with $-4.05leqmbox[Fe/H]leq-2.33$, based on high-resolution (R $sim28,000$) Magellan/MIKE spectra. Eight of our stars have low heavy-element abundances of $mbox[Sr/H]<-4.5$ and $mbox[Ba/H]<-4.0$, making them Small Accreted Stellar System (SASS) stars. Four are hyper neutron-capture-element poor with $mbox[Sr/H]<-5.0$, including Gaia […]