Johanna M. Nagy
A5082480097- Radio Astronomy Observations and Technology
- Superconducting and THz Device Technology
- Cosmology and Gravitation Theories
- Astrophysics and Cosmic Phenomena
- Adaptive optics and wavefront sensing
- Dark Matter and Cosmic Phenomena
- Galaxies: Formation, Evolution, Phenomena
- Aerospace Engineering and Energy Systems
- Astronomy and Astrophysical Research
- Advanced Thermodynamic Systems and Engines
- Spacecraft Design and Technology
- Spacecraft and Cryogenic Technologies
- Computational Physics and Python Applications
- Atmospheric Ozone and Climate
- Particle Detector Development and Performance
- Geophysics and Gravity Measurements
- Stellar, planetary, and galactic studies
- Cryospheric studies and observations
- Pulsars and Gravitational Waves Research
- Scientific Research and Discoveries
- Astrophysics and Star Formation Studies
- Gamma-ray bursts and supernovae
- Atmospheric and Environmental Gas Dynamics
- Planetary Science and Exploration
- Astronomical Observations and Instrumentation
Case Western Reserve University
2012-2025
Washington University in St. Louis
2020-2023
University of Chicago
2012-2022
University of Toronto
2016-2021
Canadian Institute for Theoretical Astrophysics
2016-2021
Cardiff University
2012-2020
California Institute of Technology
2020
National Institute of Standards and Technology
2016
University of California, Berkeley
2012
Brookhaven National Laboratory
2007
Abstract We present the first linear polarization measurements from 2015 long-duration balloon flight of Spider , which is an experiment that designed to map cosmic microwave background (CMB) on degree angular scales. The results these include maps and power spectra observations 4.8% sky at 95 150 GHz, along with internal consistency tests data. While polarized CMB anisotropy primordial density perturbations dominant signal in this region sky, Galactic dust emission also detected high...
Inflation may provide unique insight into the physics at highest available energy scales that cannot be replicated in any realistic terrestrial experiment. Features primordial power spectrum are generically predicted a wide class of models inflation and its alternatives, observationally one most overlooked channels for finding evidence non-minimal inflationary models. Constraints from observations cosmic microwave background cover widest range feature frequencies, but sensitive constraints...
CMB-S4, the next-generation ground-based cosmic microwave background (CMB) observatory, will provide detailed maps of CMB at millimeter wavelengths to dramatically advance our understanding origin and evolution universe. CMB-S4 deploy large- small-aperture telescopes with hundreds thousands detectors observe arcminute degree resolutions wavelengths. Inflationary science benefits from a deep delensing survey capable observing large field view This kind acts as complement angular resolution...
CMB-S4 is a proposed experiment to map the polarization of Cosmic Microwave Background (CMB) nearly cosmic variance limit for angular scales that are accessible from ground. The science goals and capabilities in illuminating inflation, measuring sum neutrino masses, searching relativistic relics early universe, characterizing dark energy matter, mapping matter distribution universe have been described Science Book. This Technology Book companion volume ambitious CMB-S4, "Stage-4" experiment,...
The hot dense environment of the early universe is known to have produced large numbers baryons, photons, and neutrinos. These extreme conditions may also other long-lived species, including new light particles (such as axions or sterile neutrinos) gravitational waves. effects any such relics can be observed through their unique imprint in cosmic microwave background (CMB), large-scale structure, primordial element abundances, are important determining initial universe. We argue that future...
Abstract Using data from the first flight of Spider and Planck High Frequency Instrument, we probe properties polarized emission interstellar dust in observing region. Component-separation algorithms operating both spatial harmonic domains are applied to their consistency quantify modeling errors associated with assumptions. Analyses diffuse Galactic spanning full region demonstrate (i) a spectral energy distribution that is broadly consistent modified-blackbody (MBB) model index β d = 1.45...
Abstract We present a new upper limit on cosmic microwave background (CMB) circular polarization from the 2015 flight of Spider , balloon-borne telescope designed to search for B -mode linear inflation. Although level in CMB is predicted be very small, experimental limits provide valuable test underlying models. By exploiting nonzero circular-to-linear coupling half-wave plate modulators, data 's Antarctic constraint Stokes V at 95 and 150 GHz range <?CDATA $33\lt {\ell }\lt 307$?> <mml:math...
We present the results of integration and characterization Spider instrument after 2013 pre-flight campaign. is a balloon-borne polarimeter designed to probe primordial gravitational wave signal in degree-scale B-mode polarization cosmic microwave background. With six independent telescopes housing over 2000 detectors 94 GHz 150 frequency bands, will map 7.5% sky with depth 11 14 μK•arcmin at each frequency, which factor ~5 improvement Planck. discuss pointing, cryogenic, electronics, power...
We describe the cryogenic half-wave plate rotation mechanisms built for and used in Spider, a polarization-sensitive balloon-borne telescope array that observed cosmic microwave background at 95 GHz 150 during stratospheric balloon flight from Antarctica January 2015. The operate liquid helium temperature flight. A three-point contact design keeps mechanical bearings relatively small but allows large (305 mm) diameter clear aperture. worm gear driven by stepper motor precise positioning...
In April to May 2023, the superBIT telescope was lifted Earth's stratosphere by a helium-filled super-pressure balloon, acquire astronomical imaging from above (99.5% of) atmosphere. It launched New Zealand then, for 40 days, circumnavigated globe five times at latitude 50 degrees South. Attached were four 'DRS' (Data Recovery System) capsules containing 5 TB solid state data storage, plus GNSS receiver, Iridium transmitter, and parachute. Data copied these, two dropped over Argentina. They...
The SPTpol camera is a dichroic polarimetric receiver at 90 and 150 GHz. Deployed in January 2012 on the South Pole Telescope (SPT), looking for faint polarization signals Cosmic Microwave Background (CMB). consists of 180 individual Transition Edge Sensor (TES) polarimeters GHz seven 84-polarimeter modules (a total 588 polarimeters) We present design, dark characterization, in-lab optical properties modules. consist photolithographed arrays TES coupled to silicon platelet corrugated...
This is a solicited whitepaper for the Snowmass 2021 community planning exercise. The paper focuses on measurements and science with Cosmic Microwave Background (CMB). CMB foundational to our understanding of modern physics continues be powerful tool driving cosmology particle physics. In this paper, we outline broad unique impact High Energy Frontier in upcoming decade. We also describe progression ground-based experiments, which shows that prepared develop key capabilities facilities...
An attitude determination system for balloon-borne experiments is presented. The provides pointing information in azimuth and elevation instruments flying on stratospheric balloons over Antarctica. In-flight given by the real-time combination of readings from star cameras, a magnetometer, sun sensors, GPS, gyroscopes, tilt sensors an encoder. Post-flight reconstruction determined camera solutions, interpolated gyroscopes using extended Kalman Filter. multi-sensor was employed Balloon-borne...
We describe 280 GHz bolometric detector arrays that instrument the balloon-borne polarimeter spider. A primary science goal of spider is to measure large-scale B-mode polarization cosmic microwave background (cmb) in search cosmic-inflation, gravitational-wave signature. channels aid this by constraining level contamination from galactic dust emission. present focal plane unit design, which consists a 16x16 array conical, corrugated feedhorns coupled monolithic fabricated on 150 mm diameter...
We present the conceptual design of modular detector and readout system for Cosmic Microwave Background – Stage four (CMB-S4) ground-based survey experiment. CMB-S4 will map cosmic microwave background (CMB) millimeter-wave sky to unprecedented sensitivity, using 500,000 superconducting detectors observing from Chile Antarctica over 60% sky. The fundamental building block is a module package operated at 100 mK, which connected amplification chain that carries signals out room temperature. It...
In January 2012, the 10m South Pole Telescope (SPT) was equipped with a polarization-sensitive camera, SPTpol, in order to measure polarization anisotropy of cosmic microwave background (CMB). Measurements CMB at small angular scales (~several arcminutes) can detect gravitational lensing by large scale structure and constrain sum neutrino masses. At (~few degrees) measurements energy Inflation. SPTpol is two-color mm-wave camera that consists 180 polarimeters 90 GHz 588 150 GHz, each...
The SPTpol camera is a two-color, polarization-sensitive bolometer receiver, and was installed on the 10 meter South Pole Telescope in January 2012. designed to study faint polarization signals Cosmic Microwave Background, with two primary scientific goals. One constrain tensor-to-scalar ratio of perturbations primordial plasma, thus space permissible inflationary models. other measure weak lensing effect large-scale structure CMB polarization, which can be used sum neutrino masses as well...
CMB-S4 – the next-generation ground-based cosmic microwave background (CMB) experiment - will significantly advance sensitivity of CMB measurements and improve our understanding origin evolution universe. deploy large-aperture telescopes fielding hundreds thousands detectors at millimeter wavelengths. We present baseline optical design concept telescopes, which consists two configurations: (i) a new off-axis, three-mirror, free-form anastigmatic (ii) existing coma-corrected crossed-Dragone...
Abstract We present an implementation of a Bayesian mixture model using Hamiltonian Monte Carlo techniques to search for the spatial separation Galactic dust populations. Utilizing intensity measurements from Planck High Frequency Instrument, we apply this high-latitude emission. Our analysis reveals strong preference spatially varying two-population over one-population model, when latter must capture total variance in sky. Each population is well characterized by single-component spectral...