Publications (14)
Why is the Galactic disk so cool?
Chris Hamilton, Shaunak Modak, Scott Tremaine
The bulk of old stars in the Galactic disk have migrated radially by up to several kpc in their lifetimes, yet the disk has remained relatively cool, i.e., the ratio of radial heat…
Cosmic-Ray Driven Galactic Winds from the Warm Interstellar Medium
Shaunak Modak, Eliot Quataert, Yan-Fei Jiang +1
We study the properties of cosmic-ray (CR) driven galactic winds from the warm interstellar medium using idealized spherically symmetric time-dependent simulations. The key ingredi…
Galactokinetics
Chris Hamilton, Shaunak Modak, Scott Tremaine
Galactic disks lie at the heart of many of the most pressing astrophysical puzzles. There are sophisticated kinetic theories that describe some aspects of galaxy disk dynamics, but…
An Analytic Model for Stellar Metallicity Gradient Residuals in Cold, Phase-Mixed Galactic Disks
Shaunak Modak, Zoe Hackshaw, Keith Hawkins
The distribution of stellar metallicities over phase space in galactic disks is sculpted by both star formation and secular orbital transport processes. As a result, chemo-dynamica…
Eccentricity dynamics of wide binaries -- II. The effect of stellar encounters and constraints on formation channels
Chris Hamilton, Shaunak Modak
GAIA wide stellar binaries (separations AU) are observed to have a superthermal eccentricity distribution function (DF), well-fit by with $…
Distinguishing Dark Matter Cusps from Cores using Globular Clusters
Shaunak Modak, Shany Danieli, Jenny E. Greene
Globular Clusters (GCs) provide valuable insight into the properties of their host galaxies' dark matter halos. Using N-body simulations incorporating semianalytic dynamical fricti…
Interstellar Medium-Driven Orbital Transport -- I. Radial Heating and Migration
Shaunak Modak, Chris Hamilton, Eve C. Ostriker +1
Interstellar medium (ISM) structures gravitationally perturb stellar orbits in galactic disks, driving orbital heating and migration. However, studies of these transport processes…
Galactokinetics II: Spiral structure
Chris Hamilton, Shaunak Modak, Scott Tremaine
We present a unified theory of linear spiral structure in stellar disks. We begin by identifying the characteristic scales involved in the spiral structure problem and listing some…
Record-breaking polarization from the interacting superluminous supernova 2017hcc
Jon C. Mauerhan, Nathan Smith, G. Grant Williams +12
We present multiepoch spectropolarimetry of the superluminous interacting Type IIn supernova SN2017hcc, covering 16 to 391 days after explosion. In our first epoch we measure conti…
The Zwicky Transient Facility Bright Transient Survey. II. A Public Statistical Sample for Exploring Supernova Demographics
Daniel A. Perley, Christoffer Fremling, Jesper Sollerman +34
We present a public catalog of transients from the Zwicky Transient Facility (ZTF) Bright Transient Survey (BTS), a magnitude-limited (m<19 mag in either the g or r filter) survey…
Characterizing Density and Gravitational Potential Fluctuations of the Interstellar Medium
Shaunak Modak, Eve C. Ostriker, Chris Hamilton +1
Substructure in the interstellar medium (ISM) is crucial for establishing the correlation between star formation and feedback and has the capacity to significantly perturb stellar…
The Lick Observatory Supernova Search follow-up program: photometry data release of 70 stripped-envelope supernovae
WeiKang Zheng, Benjamin E. Stahl, Thomas de Jaeger +85
We present BVRI and unfiltered Clear light curves of 70 stripped-envelope supernovae (SESNe), observed between 2003 and 2020, from the Lick Observatory Supernova Search (LOSS) foll…
Eccentricity dynamics of wide binaries -- I. The effect of Galactic tides
Shaunak Modak, Chris Hamilton
A major puzzle concerning the wide stellar binaries (semimajor axes \,AU) in the Solar neighborhood is the origin of their observed superthermal eccentricity distrib…
The Gravity Collective: A Search for the Electromagnetic Counterpart to the Neutron Star-Black Hole Merger GW190814
Charles D. Kilpatrick, David A. Coulter, Iair Arcavi +79
We present optical follow-up imaging obtained with the Katzman Automatic Imaging Telescope, Las Cumbres Observatory Global Telescope Network, Nickel Telescope, Swope Telescope, and…