A5017507375- Astro and Planetary Science
- Gamma-ray bursts and supernovae
- Solar and Space Plasma Dynamics
- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- Planetary Science and Exploration
- Pulsars and Gravitational Waves Research
- Galaxies: Formation, Evolution, Phenomena
- Isotope Analysis in Ecology
- Advanced Research in Science and Engineering
- Radiation Therapy and Dosimetry
- Advanced Chemical Physics Studies
- Spectroscopy and Laser Applications
- Geophysics and Gravity Measurements
- Methane Hydrates and Related Phenomena
- Atomic and Molecular Physics
- Space Science and Extraterrestrial Life
- Nuclear physics research studies
- Astronomical Observations and Instrumentation
- Quantum, superfluid, helium dynamics
- Metal-Catalyzed Oxygenation Mechanisms
- Lightning and Electromagnetic Phenomena
- Geomagnetism and Paleomagnetism Studies
- Electrostatic Discharge in Electronics
- Advanced Electrical Measurement Techniques
Boston University
2023-2024
University of Minnesota System
2022-2024
University of Illinois Urbana-Champaign
2020-2023
University of Minnesota
2023
European Organization for Nuclear Research
2023
King's College London
2023
University of Notre Dame
2023
Johns Hopkins University Applied Physics Laboratory
2023
Washington State University
2014-2015
University of Wisconsin–Madison
2014-2015
We investigate the impact of high optical depth on HI saturation observed in Perseus molecular cloud by using Arecibo emission and absorption measurements toward 26 radio continuum sources. The spin temperature individual components are derived along each line-of-sight, enabling us to estimate correction for depth. examine two different methods correction, Gaussian decomposition isothermal methods, find that they consistent (maximum factor ~ 1.2) likely due relatively low insignificant...
The Late Devonian was a protracted period of low speciation resulting in biodiversity decline, culminating extinction events near the Devonian-Carboniferous boundary. Recent evidence indicates that final event may have coincided with dramatic drop stratospheric ozone, possibly due to global temperature rise. Here we study an alternative possible cause for postulated ozone drop: nearby supernova explosion could inflict damage by accelerating cosmic rays can deliver ionizing radiation up $\sim...
(Abridged) Using the Arecibo Observatory we have obtained neutral hydrogen (HI) absorption and emission spectral pairs in direction of 26 background radio continuum sources vicinity Perseus molecular cloud. Strong lines were detected all cases allowing us to estimate spin temperature (T_s) optical depth for 107 individual Gaussian components along these sight. Basic properties HI clouds (spin temperature, depth, column density cold warm medium, CNM WNM) around are very similar those found...
Abstract The widespread detection of 60 Fe in geological and lunar archives provides compelling evidence for recent nearby supernova explosions within ∼100 pc at 3 7 Myr ago. blasts from these had a profound effect on the heliosphere. We perform new calculations to study compression heliosphere due blast. Assuming steady but non-isotropic solar wind, we explore range properties appropriate distances inspired by data, 20 proposed account mass extinctions end-Devonian period. examine locations...
Abstract The astrophysical sites where r -process elements are synthesized remain mysterious: it is clear that neutron star mergers (kilonovae (KNe)) contribute, and some classes of core-collapse supernovae (SNe) also possible sources at least the lighter species. discovery 60 Fe on Earth Moon implies one or more explosions have occurred near within last few million years, probably SNe. Intriguingly, 244 Pu has now been detected, mostly overlapping with pulses. However, flux may extend to...
Binary neutron star (BNS) post-merger gravitational-wave emission can occur in the aftermath of a BNS merger -- provided system avoids prompt collapse to black hole as quasistable hypermassive remnant experiences quadrupolar oscillations and non-axisymmetric deformations. The spectrum possesses characteristic peak frequency that has been shown be dependent on binary chirp mass equation state (EoS), rendering gravitational waves powerful tool for constraining composition. Unfortunately,...
Most stars generate winds and move through the interstellar medium that surrounds them. This movement creates a cocoon formed by deflection of these envelops protects stars. We call “cocoons” astrospheres. The Sun has its own cocoon, heliosphere. heliosphere is an immense shield Solar System from harsh, galactic radiation. radiation enters affects life on Earth as well human space exploration. Galactic cosmic rays are dominant source principal hazard affecting missions within our System....
Abstract The Sun moves through the interstellar medium (ISM) at a velocity of ∼19 pc Myr −1 , making conditions outside solar system vary with time over millions years. Today’s is protected from particles by heliosphere, bubble formed wind as ISM, which engulfs planets. There geological evidence 60 Fe that Earth was in direct contact ISM 2–3 and 5–7 million years ago (MYA). Recent work argues encountered massive cold cloud 2 MYA part Local Ribbon Cold Clouds shrunk heliosphere exposed to...
Abstract 244 Pu has recently been discovered in deep-sea deposits spanning the past 10 Myr, a period that includes two 60 Fe pulses from nearby supernovae. is among heaviest r -process products, and we consider whether it was created supernovae, which disfavored by nucleosynthesis simulations, or an earlier kilonova event seeded interstellar medium with subsequently swept up supernova debris. We discuss how these possibilities can be probed measuring other radioisotopes such as 129 I 182 Hf,...
Iron-TAML activators of peroxides are functional mimics peroxidase and short-circuited cytochrome P450 enzymes that perform numerous transformations appear by all measures to date be fully life cycle compatible with the environment. Here we show how design same catalytic chemistry without direct addition H2O2, thereby removing need transport store hydrogen peroxide. In this new approach, dioxygen is reduced in situ D-glucose presence glucose oxidase (GO) from Aspergillus niger. The resulting...
There is now solid experimental evidence of at least one supernova explosion within 100 pc Earth the last few million years, from measurements short-lived isotope 60Fe in widespread deep-ocean samples, as well lunar regolith and cosmic rays. This first established example a specific dated astrophysical event outside Solar System having measurable impact on Earth, offering new probes stellar evolution, nuclear astrophysics, astrophysics solar neighborhood, cosmic-ray sources acceleration,...
Abstract We discuss the synergies between heliospheric and dust science, open science questions, technological endeavours, programmatic aspects that are important to maintain or develop in decade come. In particular, we illustrate how can use interstellar solar system as a tracer for (dynamic) heliosphere properties, emphasize fairly unexplored, but potentially question of role cosmic astrospheric physics. show an probe mission with dedicated suite would bring unprecedented advances...
We live in a dynamic star-forming galaxy, and as result the solar neighborhood changes constantly.One of most spectacular events that inevitably occurs is explosion supernova near Earth.Remarkably, wealth evidence now shows at least two supernovae occurred during past 10 Myr within ∼ 100 pc Earth.We summarize these data, notably detection radioactive 60 Fe deep sea, Antarctic snow, Moon.Analytic estimates hydrodynamic simulations show heliospheric response was dramatic, with heliopause...
We investigated the perception of lactation experience at work and relationship between taking time academic productivity among neurology women faculty.
Our solar system's path has recently been shown to potentially intersect dense interstellar clouds 2 and 7 million years ago: the Local Lynx of Cold Cloud edge Bubble. These compressed heliosphere, directly exposing Earth medium. Previous studies that examined climate effects these encounters argued for an induced ice age due formation global noctilucent (NLCs). Here, we revisit such with a modern 2D atmospheric chemistry model using parameters heliospheric magnetohydrodynamic models as...
Supernova blasts envelop many surrounding stellar systems, transferring kinetic energy to small bodies in the systems. Geologic evidence from $^{60}\rm Fe$ points recent nearby supernova activity within past several Myr. Here, we model transfer of and resulting orbital changes these Oort Cloud, Kuiper belt, Saturn's Phoebe ring. For an impulse approximation shows that a 50 pc can eject approximately half all objects less than 1 cm while altering trajectories larger ones, depending on their...
Whitepaper #038 in the Decadal Survey for Solar and Space Physics (Heliophysics) 2024-2033. Main topics: basic research. Additional outer heliosphere; space-based missions/projects; emerging opportunities.
Whitepaper #377 in the Decadal Survey for Solar and Space Physics (Heliophysics) 2024-2033. Main topics: basic research; infrastructure/workforce/other programmatic. Additional other outer heliosphere; programmatic; space-based [...]