It’s a matter of time: Empirical Constraints on Supernova Yields and Delay Times from Dwarf Spheroidal Galaxies

Posted by klaurent Chicago

Kavli Affiliate: Alexander Ji | Summary:The chemical abundances of a stellar population encode information about nucleosynthesis and its astrophysical sites, but this information is confounded by the specific star formation history of the host galaxy. As a result, placing empirical constraints on supernova yields and timing using abundances has been very challenging. We introduce a […]


Continue.. It’s a matter of time: Empirical Constraints on Supernova Yields and Delay Times from Dwarf Spheroidal Galaxies

A steadily declining dispersion measure for the repeating fast radio burst FRB 20220529A: Evidence for an FRB engine embedded in an expanding supernova remnant

Posted by klaurent MIT

Kavli Affiliate: Kiyoshi Masui | Summary:We present the discovery and subsequent 3.2 year monitoring campaign of the repeating fast radio burst FRB 20220529A with CHIME/FRB. We observe a gradual dispersion measure (DM) decline of $-0.881pm0.001~mathrmpc~mathrmcm^-3~mathrmyear^-1$ ($-1.235pm0.001~mathrmpc~mathrmcm^-3~mathrmyear^-1$ in the rest frame), implying a $geq3.5pm0.2$% decrease of the total electron column in the source environment, and we […]


Continue.. A steadily declining dispersion measure for the repeating fast radio burst FRB 20220529A: Evidence for an FRB engine embedded in an expanding supernova remnant

A steadily declining dispersion measure for the repeating fast radio burst FRB 20220529A: Evidence for an FRB engine embedded in an expanding supernova remnant

Posted by klaurent MIT

Kavli Affiliate: Kiyoshi Masui | Summary:We present the discovery and subsequent 3.2 year monitoring campaign of the repeating fast radio burst FRB 20220529A with CHIME/FRB. We observe a gradual dispersion measure (DM) decline of $-0.881pm0.001~mathrmpc~mathrmcm^-3~mathrmyear^-1$ ($-1.235pm0.001~mathrmpc~mathrmcm^-3~mathrmyear^-1$ in the rest frame), implying a $geq3.5pm0.2$% decrease of the total electron column in the source environment, and we […]


Continue.. A steadily declining dispersion measure for the repeating fast radio burst FRB 20220529A: Evidence for an FRB engine embedded in an expanding supernova remnant

AT2024lhc and AT2024kmq in the landscape of featureless tidal disruption events

Posted by klaurent MIT

Kavli Affiliate: Dheeraj Pasham | Summary:We study AT2024kmq and AT2024lhc, two tidal disruption events (TDEs) with blue featureless spectra associated with high-mass black holes ($M_rm BHsim 10^8,M_odot$). Both events show optical precursors consistent with shock dissipation from stream self-intersection. Their X-ray emission is luminous ($L_rm Xsim 10^44,rm erg,s^-1$), highly variable (with minimum observed variability timescales […]


Continue.. AT2024lhc and AT2024kmq in the landscape of featureless tidal disruption events

A generalized synthetic control algorithm for sparse functional data

Posted by dbos UCSD / Salk

Kavli Affiliate: Wesley Thompson | Authors: Lucy Shao, Kilian M. Pohl and Wesley K. Thompson | Summary: The Synthetic Control Method (SCM) and its interactive factor model generalizations (GSC) are powerful for estimating causal effects from panel data but are not easily applied when follow-up is irregular or sparse, common features of biomedical cohorts. We […]


Continue.. A generalized synthetic control algorithm for sparse functional data

Designing heterostructures to control oxygen stoichiometry in helimagnetic perovskite strontium ferrite

Posted by klaurent Cornell

Kavli Affiliate: David Muller | Summary:A large challenge in determining the physics of helimagnetic SrFeO3 is in stabilizing the stoichiometric chemical phase over long enough time scales to conduct extensive measurements. Degradation in SrFeO3 manifests mainly as a crossover from metallic to insulating behavior. Using a combination of electronic transport and density functional theory, we […]


Continue.. Designing heterostructures to control oxygen stoichiometry in helimagnetic perovskite strontium ferrite

Designing heterostructures to control oxygen stoichiometry in helimagnetic perovskite strontium ferrite

Posted by klaurent Cornell

Kavli Affiliate: David Muller | Summary:A large challenge in determining the physics of helimagnetic SrFeO3 is in stabilizing the stoichiometric chemical phase over long enough time scales to conduct extensive measurements. Degradation in SrFeO3 manifests mainly as a crossover from metallic to insulating behavior. Using a combination of electronic transport and density functional theory, we […]


Continue.. Designing heterostructures to control oxygen stoichiometry in helimagnetic perovskite strontium ferrite

The DECam MAGIC Survey: Uncovering the Tidal Tails of the Crater II Dwarf Galaxy

Posted by klaurent Chicago

Kavli Affiliate: Alexander Ji | Summary:Crater II (CraII), a large and low-density dwarf spheroidal galaxy, has unusual observed properties that are difficult to reproduce in cold dark matter simulations. Ongoing tidal disruption may help explain the discrepancies, as evidenced by the recent discovery of tidal tails. Here we present metallicity-sensitive narrowband photometry of the Ca […]


Continue.. The DECam MAGIC Survey: Uncovering the Tidal Tails of the Crater II Dwarf Galaxy

A Path to an All-Sky Survey with Roman

Posted by klaurent Stanford

Kavli Affiliate: Susan Clark | Summary:A deep, space-based, all-sky near-infrared survey carried out with the Nancy Grace Roman Space Telescope would constitute a foundational astronomical infrastructure for decades to come. In this white paper, we present a concrete and feasible path to imaging the entire sky at $sim0.1”$ resolution, beginning with high-impact fields in Cycle […]


Continue.. A Path to an All-Sky Survey with Roman

The DECam MAGIC Survey: Uncovering the Tidal Tails of the Crater II Dwarf Galaxy

Posted by klaurent Chicago

Kavli Affiliate: Alexander Ji | Summary:Crater II (CraII), a large and low-density dwarf spheroidal galaxy, has unusual observed properties that are difficult to reproduce in cold dark matter simulations. Ongoing tidal disruption may help explain the discrepancies, as evidenced by the recent discovery of tidal tails. Here we present metallicity-sensitive narrowband photometry of the Ca […]


Continue.. The DECam MAGIC Survey: Uncovering the Tidal Tails of the Crater II Dwarf Galaxy