Characterization of atmospheric turbulence for the Large Synoptic Survey Telescope

Kavli Affiliate: Patricia Burchat | Summary:One of the scientific goals of the Large Synoptic Survey Telescope (LSST) is to measure the evolution of dark energy by measuring subtle distortions of galaxy shapes due to weak gravitational lensing caused by the evolving dark matter distribution. Understanding the point spread function (PSF) for LSST is a crucial […]


Continue.. Characterization of atmospheric turbulence for the Large Synoptic Survey Telescope

Characterization of lemniscate atmospheric aberrations in Gemini Planet Imager data

Kavli Affiliate: Bruce A. Macintosh | First 5 Authors: Alexander Madurowicz, Bruce A. Macintosh, Jean-Baptiste Ruffio, Jeffery Chilcote, Vanessa P. Bailey | Summary: A semi analytic framework for simulating the effects of atmospheric seeing in Adaptive Optics systems on an 8-m telescope is developed with the intention of understanding the origin of the wind-butterfly, a […]


Continue.. Characterization of lemniscate atmospheric aberrations in Gemini Planet Imager data

Production Rate Measurement of Tritium and Other Cosmogenic Isotopes in Germanium with CDMSlite

Kavli Affiliate: Blas Cabrera | Summary:Future direct searches for low-mass dark matter particles with germanium detectors, such as SuperCDMS SNOLAB, are expected to be limited by backgrounds from radioactive isotopes activated by cosmogenic radiation inside the germanium. There are limited experimental data available to constrain production rates and a large spread of theoretical predictions. We […]


Continue.. Production Rate Measurement of Tritium and Other Cosmogenic Isotopes in Germanium with CDMSlite

Energy Loss Due to Defect Formation from $^206$Pb Recoils in SuperCDMS Germanium Detectors

Kavli Affiliate: Blas Cabrera | Summary:The Super Cryogenic Dark Matter Search experiment (SuperCDMS) at the Soudan Underground Laboratory studied energy loss associated with Frenkel defect formation in germanium crystals at mK temperatures using in situ $^210$Pb sources. We examine the spectrum of $^206$Pb nuclear recoils near its expected 103 keV endpoint energy and determine an […]


Continue.. Energy Loss Due to Defect Formation from $^206$Pb Recoils in SuperCDMS Germanium Detectors

Statistical analysis of acoustic wave power and flows around solar active regions

Kavli Affiliate: Philip H. Scherrer | Summary:We analyze the effect of a sunspot in its quiet surroundings applying a helioseismic technique on almost three years of Helioseismic and Magnetic Imager (HMI) observations obtained during solar cycle 24 to further study the sunspot structure below the solar surface. The attenuation of acoustic waves with frequencies lower […]


Continue.. Statistical analysis of acoustic wave power and flows around solar active regions

Defining Pathway Assembly and Exploring its Applications

Kavli Affiliate: Stuart Marshall | Summary:How do we estimate the probability of an abundant objects’ formation, with minimal context or assumption about is origin? To explore this we have previously introduced the concept of pathway assembly (as pathway complexity), in a graph based context, as an approach to quantify the number of steps required to […]


Continue.. Defining Pathway Assembly and Exploring its Applications

On-Orbit Performance of the Helioseismic and Magnetic Imager Instrument onboard the Solar Dynamics Observatory

Kavli Affiliate: Philip H. Scherrer | Summary:The Helioseismic and Magnetic Imager (HMI) instrument is a major component of NASA’s Solar Dynamics Observatory (SDO) spacecraft. Since beginning normal science operations on 1 May 2010, HMI has operated with remarkable continuity, e.g. during the more than five years of the SDO prime mission that ended 30 September […]


Continue.. On-Orbit Performance of the Helioseismic and Magnetic Imager Instrument onboard the Solar Dynamics Observatory

Thermal detection of single e-h pairs in a biased silicon crystal detector

Kavli Affiliate: Blas Cabrera | Summary:We demonstrate that individual electron-hole pairs are resolved in a 1 cm$^2$ by 4 mm thick silicon crystal (0.93 g) operated at $sim$35 mK. One side of the detector is patterned with two quasiparticle-trap-assisted electro-thermal-feedback transition edge sensor (QET) arrays held near ground potential. The other side contains a bias […]


Continue.. Thermal detection of single e-h pairs in a biased silicon crystal detector

ProtoDESI: First On-Sky Technology Demonstration for the Dark Energy Spectroscopic Instrument

Kavli Affiliate: Kevin Reil | Summary:The Dark Energy Spectroscopic Instrument (DESI) is under construction to measure the expansion history of the universe using the baryon acoustic oscillations technique. The spectra of 35 million galaxies and quasars over 14,000 square degrees will be measured during a 5-year survey. A new prime focus corrector for the Mayall […]


Continue.. ProtoDESI: First On-Sky Technology Demonstration for the Dark Energy Spectroscopic Instrument

DES Science Portal: Computing Photometric Redshifts

Kavli Affiliate: Rafe Schindler | Summary:A significant challenge facing photometric surveys for cosmological purposes is the need to produce reliable redshift estimates. The estimation of photometric redshifts (photo-zs) has been consolidated as the standard strategy to bypass the high production costs and incompleteness of spectroscopic redshift samples. Training-based photo-z methods require the preparation of a […]


Continue.. DES Science Portal: Computing Photometric Redshifts