papers

Publications (81)

astro-ph.IM2019

The Wide Field Infrared Survey Telescope: 100 Hubbles for the 2020s

Rachel Akeson, Lee Armus, Etienne Bachelet +103

The Wide Field Infrared Survey Telescope (WFIRST) is a 2.4m space telescope with a 0.281 deg^2 field of view for near-IR imaging and slitless spectroscopy and a coronagraph designe…

astro-ph.GA2024

Local Analogs of Primordial Galaxies: In Search of Intermediate Mass Black Holes with JWST NIRSpec

Sara Doan, Shobita Satyapal, William Matzko +15

Local low metallicity galaxies with signatures of possible accretion activity are ideal laboratories in which to search for the lowest mass black holes and study their impact on th…

cs.AI2022

Predictive Coding: a Theoretical and Experimental Review

Beren Millidge, Anil Seth, Christopher L Buckley

Predictive coding offers a potentially unifying account of cortical function -- postulating that the core function of the brain is to minimize prediction errors with respect to a g…

astro-ph.GA2023

The Panchromatic Hubble Andromeda Treasury XXI. The Legacy Resolved Stellar Photometry Catalog

Benjamin F. Williams, Meredith Durbin, Dustin Lang +14

We present the final legacy version of stellar photometry for the Panchromatic Hubble Andromeda Treasury (PHAT) survey. We have reprocessed all of the Hubble Space Telescope (HST)…

astro-ph.CO2011

Constraining the role of star cluster mergers in nuclear cluster formation: Simulations confront integral-field data

Markus Hartmann, Victor P. Debattista, Anil Seth +2

We present observations and dynamical models of the stellar nuclear clusters (NCs) at the centres of NGC 4244 and M33. We then compare these to an extensive set of simulations test…

astro-ph.GA2024

Towards Understanding the Milky Way's Typicality: Assessing the Chemodynamics of M31's Bulge & Bar, Thick & Thin Discs

Benjamin J. Gibson, Gail Zasowski, Anil Seth +6

We describe a novel framework to model galaxy spectra with two cospatial stellar populations, such as may represent a bulge & bar or thick & thin disc, and apply it to APOGEE spect…

astro-ph.HE2026

The Intermediate Mass Black Hole in Omega Centauri: Constraints on Accretion from JWST

Steven Chen, Jeremy Hare, Oleg Kargaltsev +4

We analyze JWST observations of the central region of the globular cluster Centauri (NGC 5139, Cen hereafter), around the position of the candidate IMBH inferred by \cite…

astro-ph.GA2026

SDSS-V Local Volume Mapper (LVM): The Integrated Light and Internal Rotation of Omega Centauri

Maximilian Häberle, Dmitry Bizyaev, Alina Boecker +34

The SDSS-V Local Volume Mapper (LVM) is a wide-field integral field spectroscopic survey of the Southern Milky Way plane, the Magellanic Clouds, and nearby Local Group galaxies. We…

astro-ph.GA2020

Nuclear X-ray Activity in Low-Surface-Brightness Galaxies: Prospects for Constraining the Local Black Hole Occupation Fraction with a Chandra Successor Mission

Edmund Hodges-Kluck, Elena Gallo, Anil Seth +2

About half of nearby galaxies have a central surface brightness >1 magnitude below that of the sky. The overall properties of these low-surface-brightness galaxies (LSBGs) remain u…

astro-ph.GA2017

A Multi-wavelength Study of the Turbulent Central Engine of the Low-mass AGN hosted by NGC404

Kristina Nyland, Timothy A. Davis, Dieu D. Nguyen +9

The nearby dwarf galaxy NGC404 harbors a low-luminosity active galactic nucleus (AGN) powered by the lowest-mass (< 150,000 solar-masses) central massive black hole (MBH) with a dy…

astro-ph.GA2020

Nuclear Star Clusters

Nadine Neumayer, Anil Seth, Torsten Boeker

We review the current knowledge about nuclear star clusters (NSCs), the spectacularly dense and massive assemblies of stars found at the centers of most galaxies. Recent observatio…

astro-ph2003

Star Clusters in Virgo and Fornax Dwarf Irregular Galaxies

Anil Seth, Knut Olsen, Bryan Miller +2

We present the results of a search for clusters in dwarf irregular galaxies in the Virgo and Fornax Cluster using HST WFPC2 snapshot data. The galaxy sample includes 28 galaxies, 1…

q-bio.NC2020

Relaxing the Constraints on Predictive Coding Models

Beren Millidge, Alexander Tschantz, Anil Seth +1

Predictive coding is an influential theory of cortical function which posits that the principal computation the brain performs, which underlies both perception and learning, is the…

astro-ph.GA2017

Detection of Enhanced Central Mass-to-Light Ratios in Low-Mass Early-Type Galaxies: Evidence for Black Holes?

Renuka Pechetti, Anil Seth, Michele Cappellari +4

We present dynamical measurements of the central mass-to-light ratio () of a sample of 27 low-mass early-type ATLAS galaxies. We consider all ATLAS galaxies with…

astro-ph.CO2011

Star Clusters in M31: V. Internal Dynamical Trends: Some Troublesome, Some Reassuring

Jay Strader, Nelson Caldwell, Anil Seth

We present internal velocity dispersions and precise radial velocities for 200 globular clusters (GCs) in M31 that are derived using new high-resolution spectra from MMT/Hectochell…

astro-ph.GA2026

A Long Period Stellar-Mass Black Hole Binary in Centauri

Matthew Whitaker, Evan Kerr, Anil Seth +16

Modern simulations of stellar dynamics in globular clusters peg a dominant role for stellar-mass black holes, but direct evidence for black holes in clusters remains limited. We pr…

astro-ph.GA2026

ReveaLLAGN 1: JWST Emission-Line Spectra Reveal Low-Luminosity AGN with UV-Deficient SEDs and Warm Molecular Gas

Kameron Goold, Anil Seth, Mallory Molina +20

We present near- and mid-infrared spectra of eight Low-Luminosity Active Galactic Nuclei (LLAGN), spanning nearly four orders of magnitude in black hole mass and Eddington ratio, o…

astro-ph.HE2019

Towards a high accuracy measurement of the local black hole occupation fraction in low mass galaxies

Elena Gallo, Edmund Hodges-Kluck, Tommaso Treu +7

This document illustrates the feasibility of a few per cent level measurement of the local black hole occupation fraction in low mass galaxies through wide-field, high angular reso…

astro-ph.GA2016

The Black Hole - Bulge Mass Relation in Megamaser Host Galaxies

Ronald Läsker, Jenny E. Greene, Anil Seth +4

We present HST images for nine megamaser disk galaxies with the primary goal of studying photometric BH-galaxy scaling relations. The megamaser disks provide the highest-precision…

astro-ph.GA2015

A tidally disrupting dwarf galaxy in the halo of NGC 253

Elisa Toloba, David Sand, Kristine Spekkens +7

We report the discovery of Scl-MM-Dw2, a new dwarf galaxy at a projected separation of 50 kpc from NGC 253, as part of the PISCeS (Panoramic Imaging Survey of Centaurus and S…

q-bio.NC2023

Minimum-phase property of the hemodynamic response function, and implications for Granger Causality in fMRI

Leonardo Novelli, Lionel Barnett, Anil Seth +1

Granger Causality (GC) is widely used in neuroimaging to estimate directed statistical dependence among brain regions using time series of brain activity. An important issue is tha…

astro-ph.GA2021

Relics of Supermassive Black Hole Seeds: The Discovery of an Accreting Black Hole in an Optically Normal, Low Metallicity Dwarf Galaxy

Jenna M. Cann, Shobita Satyapal, Barry Rothberg +11

The detection and characterization of supermassive black holes (SMBHs) in local low mass galaxies is crucial to our understanding of the origins of SMBHs. This statement assumes th…

astro-ph.CO2010

Nuclear Star Clusters and Black Holes

Anil Seth, Michele Cappellari, Nadine Neumayer +8

We summarize the recent results of our survey of the nearest nuclear star clusters. The purpose of the survey is to understand nuclear star cluster formation mechanisms and constra…

astro-ph.GA2022

Young, blue, and isolated stellar systems in the Virgo Cluster. II. A new class of stellar system

Michael G. Jones, David J. Sand, Michele Bellazzini +21

We discuss five blue stellar systems in the direction of the Virgo cluster, analogous to the enigmatic object SECCO 1 (AGC 226067). These objects were identified based on their opt…

astro-ph2005

The Vertical Structure of Stars in Edge-on Galaxies

Anil Seth, Julianne Dalcanton, Roelof de Jong

We present a summary of our recent work on the vertical distribution of the resolved stellar populations in six low mass, edge-on, spiral galaxies observed with the Hubble Space Te…

cs.LG2021

Understanding the Origin of Information-Seeking Exploration in Probabilistic Objectives for Control

Beren Millidge, Anil Seth, Christopher Buckley

The exploration-exploitation trade-off is central to the description of adaptive behaviour in fields ranging from machine learning, to biology, to economics. While many approaches…

astro-ph.GA2026

Jet-driven shocks and turbulence in radio-loud Active Galactic Nuclei observed with JWST MIRI/MRS

Rogemar A. Riffel, Gabriel L. Souza-Oliveira, Luis Colina +34

Jet-cloud interactions are a key manifestation of Active Galactic Nucleus (AGN) feedback on nuclear scales, distinct from the large-scale radio-mode feedback that suppresses gas co…

astro-ph.GA2014

The HST/ACS Coma Cluster Survey. X. Nuclear star clusters in low-mass early-type galaxies: scaling relations

Mark den Brok, Reynier F. Peletier, Anil Seth +16

We present scaling relations between structural properties of nuclear star clusters and their host galaxies for a sample of early-type dwarf galaxies observed as part of the Hubble…

astro-ph.IM2009

Training the Next Generation of Astronomers

Peter K. G. Williams, Eric Huff, Holly Maness +28

While both society and astronomy have evolved greatly over the past fifty years, the academic institutions and incentives that shape our field have remained largely stagnant. As a…

astro-ph.CO2013

The Densest Galaxy

Jay Strader, Anil Seth, Duncan Forbes +8

We report the discovery of a remarkable ultra-compact dwarf galaxy around the massive Virgo elliptical galaxy NGC 4649 (M60), which we term M60-UCD1. With a dynamical mass of 2.0 x…

astro-ph.CO2011

M94 As A Unique Testbed for Black Hole Mass Estimates and AGN Activity At Low Luminosities

Anca Constantin, Anil Seth

We discuss the peculiar nature of the nucleus of M94 (NGC 4736) in the context of new measurements of the broad H_alpha emission from HST-STIS observations. We show that this compo…

astro-ph.GA2019

Surprisingly Strong K-band Emission Found in Low Luminosity Active Galactic Nuclei

Antoine Dumont, Anil Seth, Jay Strader +3

We examine the near-infrared (NIR) emission from low-luminosity AGNs (LLAGNs). Our galaxy sample includes 15 objects with detected 2-10 keV X-ray emission, dynamical black hole mas…

astro-ph.GA2014

Measuring Consistent Masses for 25 Milky Way Globular Clusters

Brian Kimmig, Anil Seth, Inese I. Ivans +4

We present central velocity dispersions, masses, mass to light ratios (s), and rotation strengths for 25 Galactic globular clusters. We derive radial velocities of 1951 stars…

astro-ph.HE2012

Two stellar-mass black holes in the globular cluster M22

Jay Strader, Laura Chomiuk, Thomas Maccarone +2

Hundreds of stellar-mass black holes likely form in a typical globular star cluster, with all but one predicted to be ejected through dynamical interactions. Some observational sup…

astro-ph.GA2019

Astro2020 Science White Paper: The Local Relics of of Supermassive Black Hole Seeds

Jenny E Greene, Aaron Barth, Andrea Bellini +18

We have compelling evidence for stellar-mass black holes (BHs) of ~5-80 M_sun that form through the death of massive stars. We also have compelling evidence for so-called supermass…

astro-ph.CO2013

A Multi-Wavelength Analysis of NGC 4178: A Bulgeless Galaxy with an AGN

Nathan Secrest, Shobita Satyapal, Sean Moran +5

We present {\it Gemini} longslit optical spectroscopy and VLA radio observations of the nuclear region of NGC 4178, a late-type bulgeless disk galaxy recently confirmed to host an…

astro-ph2006

The Binary Nucleus in VCC 128: A Candidate Supermassive Black Hole in a Dwarf Elliptical Galaxy

Victor P. Debattista, Ignacio Ferreras, Anna Pasquali +3

{\it Hubble Space Telescope} (\hst) Wide Field Planetary Camera 2 ({\it WFPC2}) images of the Virgo Cluster dwarf elliptical galaxy VCC 128 reveal an apparently double nucleus. The…

astro-ph2007

Resolving the Outer Disks and Halos of Nearby Galaxies

Anil Seth, Roelof de Jong, David Radburn-Smith +1

In a hierarchical merging scenario, the outer parts of a galaxy are a fossil record of the galaxy's early history. Observations of the outer disks and halos of galaxies thus provid…

astro-ph2008

Radio continuum observations of the candidate supermassive black hole in the dwarf elliptical VCC128

Pieter Buyle, Sven De Rijcke, Victor P. Debattista +4

The presence of black holes (BHs) at the centers of dwarf elliptical galaxies (dEs) has been argued both theoretically and observationally. Using archival HST/WFPC2 data, we found…

astro-ph.GA2026

JWST Reveals Compact Nuclear Starbursts Masquerading as AGNs in Metal-Poor Dwarfs: Where Are the Accreting Intermediate-Mass Black Holes?

William Matzko, Shobita Satyapal, Jeffrey D. Mckaig +19

We present JWST/NIRSpec spectroscopy of the low-mass, metal-poor galaxy SDSS~J160135.95+311353.7 (J1601), selected for its extreme mid-infrared colors and compact nuclear emission,…

astro-ph.GA2023

The Panchromatic Hubble Andromeda Treasury: Triangulum Extended Region (PHATTER). V. The Structure of M33 in Resolved Stellar Populations

Adam Smercina, Julianne J. Dalcanton, Benjamin F. Williams +13

We present a detailed analysis of the the structure of the Local Group flocculent spiral galaxy M33, as measured using the Panchromatic Hubble Andromeda Treasury Triangulum Extende…

astro-ph.GA2014

A Supermassive Black Hole in an Ultracompact Dwarf Galaxy

Anil Seth, Remco van den Bosch, Steffen Mieske +11

Ultracompact dwarf galaxies (UCDs) are among the densest stellar systems in the universe. These systems have masses up to 200 million solar masses, but half light radii of just 3-5…

astro-ph.GA2025

Fast-moving stars around an intermediate-mass black hole in Omega Centauri

Maximilian Häberle, Nadine Neumayer, Anil Seth +15

Black holes have been found over a wide range of masses, from stellar remnants with masses of 5-150 solar masses (Msun), to those found at the centers of galaxies with Msu…

astro-ph.GA2019

Luminosity Models and Density Profiles for Nuclear Star Clusters for a Nearby Volume-Limited Sample of 29 Galaxies

Renuka Pechetti, Anil Seth, Nadine Neumayer +3

Nuclear Star Clusters (NSCs) are dense clusters of stars that reside in the centers of a majority of the galaxies. In this paper, we study the density profiles for 29 galaxies in a…

astro-ph.GA2021

The TREX Survey: Kinematical Complexity Throughout M33's Stellar Disk and Evidence for a Stellar Halo

Karoline M. Gilbert, Amanda C. N. Quirk, Puragra Guhathakurta +9

We present initial results from a large spectroscopic survey of stars throughout M33's stellar disk. We analyze a sample of 1667 red giant branch (RGB) stars extending to projected…

astro-ph2005

The UV, Optical, and IR Properties of SDSS Sources Detected by GALEX

Marcel A. Agueros, Zeljko Ivezic, Kevin R. Covey +18

We discuss the UV, optical, and IR properties of the SDSS sources detected by GALEX as part of its All-sky Imaging Survey Early Release Observations. Virtually all of the GALEX sou…

astro-ph2005

Extragalactic Thick Disks: Implications for Early Galaxy Evolution

Julianne J. Dalcanton, Anil Seth, Peter Yoachim

I briefly review the growing evidence that thick stellar disks surround most edge-on disk galaxies. Recent studies show that these extragalactic thick disks have old ages, low meta…

q-bio.NC2022

A continuity of Markov blanket interpretations under the Free Energy Principle

Anil Seth, Tomasz Korbak, Alexander Tschantz

Bruineberg and colleagues helpfully distinguish between instrumental and ontological interpretations of Markov blankets, exposing the dangers of using the former to make claims abo…

astro-ph.GA2025

oMEGACat. VI. Analysis of the overall kinematics of Omega Centauri in 3D: velocity dispersion, kinematic distance, anisotropy, and energy equipartition

Maximilian Häberle, Nadine Neumayer, Callie Clontz +15

Omega Centauri ( Cen) is the Milky Way's most massive globular cluster and is likely the stripped nucleus of an accreted dwarf galaxy. In this paper, we analyze Cen's kine…

astro-ph.IM2019

Using Contour Trees in the Analysis and Visualization of Radio Astronomy Data Cubes

Paul Rosen, Anil Seth, Betsy Mills +5

The current generation of radio and millimeter telescopes, particularly the Atacama Large Millimeter Array (ALMA), offers enormous advances in observing capabilities. While these a…

astro-ph2008

The Coincidence of Nuclear Star Clusters and Active Galactic Nuclei

Anil Seth, Marcel Agueros, Duane Lee +1

We study galaxies that host both nuclear star clusters and active galactic nuclei (AGN) implying the presence of a massive black hole. We select a sample of 176 galaxies with previ…

astro-ph.GA2020

Milky Way Analogues in MaNGA: Multi-Parameter Homogeneity and Comparison to the Milky Way

Nicholas Fraser Boardman, Gail Zasowski, Anil Seth +15

The Milky Way provides an ideal laboratory to test our understanding of galaxy evolution, owing to our ability to observe our Galaxy over fine scales. However, connecting the Galax…

astro-ph.GA2024

Centauri: A MUSE discovery of a counter-rotating core

Renuka Pechetti, Sebastian Kamann, Davor Krajnovic +7

Centauri is considered the most massive globular cluster of the Milky Way and likely the former nuclear star cluster of a galaxy accreted by the Milky Way. It is speculated to…

astro-ph.GA2022

AGC 226178 and NGVS 3543: Two deceptive dwarfs towards Virgo

Michael G. Jones, David J. Sand, Michele Bellazzini +21

The two sources AGC 226178 and NGVS 3543, an extremely faint, clumpy, blue stellar system and a low surface brightness dwarf spheroidal, are adjacent systems in the direction of th…

astro-ph.HE2012

No Evidence for Intermediate-Mass Black Holes in Globular Clusters: Strong Constraints from the JVLA

Jay Strader, Laura Chomiuk, Thomas Maccarone +4

With a goal of searching for accreting intermediate-mass black holes (IMBHs), we report the results of ultra-deep Jansky VLA radio continuum observations of the cores of three Gala…

astro-ph.IM2014

The Sloan Digital Sky Survey Reverberation Mapping Project: Technical Overview

Yue Shen, W. N. Brandt, Kyle S. Dawson +36

The Sloan Digital Sky Survey Reverberation Mapping project (SDSS-RM) is a dedicated multi-object RM experiment that has spectroscopically monitored a sample of 849 broad-line quasa…

astro-ph.GA2021

The Panchromatic Hubble Andromeda Treasury: Triangulum Extended Region (PHATTER) I. Ultraviolet to Infrared Photometry of 22 Million Stars in M33

Benjamin F. Williams, Meredith J. Durbin, Julianne J. Dalcanton +18

We present panchromatic resolved stellar photometry for 22 million stars in the Local Group dwarf spiral Triangulum (M33), derived from Hubble Space Telescope (HST) observations wi…

astro-ph.GA2014

Circumnuclear Molecular Gas in Megamaser Disk Galaxies NGC 4388 and NGC 1194

Jenny E. Greene, Anil Seth, Mariya Lyubenova +3

We explore the warm molecular and ionized gas in the centers of two megamaser disk galaxies using K-band spectroscopy. Our ultimate goal is to determine how gas is funneled onto th…

astro-ph.GA2021

Resolved nuclear kinematics link the formation and growth of nuclear star clusters with the evolution of their early and late-type hosts

Francesca Pinna, Nadine Neumayer, Anil Seth +7

We present parsec-scale kinematics of eleven nearby galactic nuclei, derived from adaptive-optics assisted integral-field spectroscopy at (near-infrared) CO band-head wavelengths.…

astro-ph.GA2021

NGC 5128 globular cluster candidates out to 150 kpc: a comprehensive catalog from Gaia and ground based data

Allison K. Hughes, David J. Sand, Anil Seth +9

We present a new catalog of 40502 globular cluster (GC) candidates in NGC 5128 out to a projected radius of 150 kpc, based on data from the Panoramic Imaging Survey of Centau…

astro-ph.CO2011

The M81 Group Dwarf Irregular Galaxy DDO 165. II. Connecting Recent Star Formation with ISM Structures and Kinematics

John M. Cannon, Hans P. Most, Evan D. Skillman +8

We compare the stellar populations and complex neutral gas dynamics of the M81 group dIrr galaxy DDO 165 using data from the HST and the VLA. Paper I identified two kinematically d…

astro-ph2006

Star Formation and Feedback in Smoothed Particle Hydrodynamic Simulations--I. Isolated Galaxies

Greg Stinson, Anil Seth, Neal Katz +3

We present an analysis of star formation and feedback recipes appropriate for galactic smoothed particle hydrodynamics simulations. Using an isolated Milky Way-like galaxy, we cons…

astro-ph.GA2018

A 3.5-million Solar Masses Black Hole in the Centre of the Ultracompact Dwarf Galaxy Fornax UCD3

Anton V. Afanasiev, Igor V. Chilingarian, Steffen Mieske +16

The origin of ultracompact dwarfs (UCDs), a class of compact stellar systems discovered two decades ago, still remains a matter of debate. Recent discoveries of central supermassiv…

astro-ph.CO2013

Using Megamaser Disks to Probe Black Hole Accretion

Jenny E. Greene, Anil Seth, Mark den Brok +7

We examine the alignment between H_2O megamaser disks on sub-pc scales with circumnuclear disks and bars on <500 pc scales observed with HST/WFC3. The HST imaging reveals young sta…

astro-ph.GA2021

Composite Bulges -- II. Classical Bulges and Nuclear Discs in Barred Galaxies: The Contrasting Cases of NGC 4608 and NGC 4643

Peter Erwin, Anil Seth, Victor P. Debattista +14

We present detailed morphological, photometric, and stellar-kinematic analyses of the central regions of two massive, early-type barred galaxies with nearly identical large-scale m…

astro-ph.GA2014

The Panchromatic Hubble Andromeda Treasury X. Ultraviolet to Infrared Photometry of 117 Million Equidistant Stars

Benjamin F. Williams, Dustin Lang, Julianne J. Dalcanton +16

We have measured stellar photometry with the Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) and Advanced Camera for Surveys (ACS) in near ultraviolet (F275W, F336W), optic…

astro-ph.GA2014

Panchromatic Hubble Andromeda Treasury IX: A Photometric Survey of Planetary Nebulae in M31

Mark J. Veyette, Benjamin F. Williams, Julianne J. Dalcanton +8

We search Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) and Wide Field Camera 3 (WFC3) broadband imaging data from the Panchromatic Hubble Andromeda Treasury (PHAT…

astro-ph2007

Detection of a Stellar Halo in NGC 4244

Anil Seth, Roelof De Jong, Julianne Dalcanton +1

We present the preliminary detection of a stellar halo in the nearby, edge-on galaxy, NGC 4244. Using data from the Hubble Space Telescope's Advanced Camera for Surveys (HST/ACS),…

astro-ph.GA2021

Detection of a 100,000 M black hole in M31's most massive globular cluster: A tidally stripped nucleus

Renuka Pechetti, Anil Seth, Sebastian Kamann +6

We investigate the presence of a central black hole (BH) in B023-G078, M31's most massive globular cluster. We present high-resolution, adaptive-optics assisted, integral-field spe…

astro-ph.GA2014

The Panchromatic Hubble Andromeda Treasury. Progression of Large-Scale Star Formation across Space and Time in M31

Dimitrios A. Gouliermis, Lori C. Beerman, Luciana Bianchi +11

We investigate the clustering of early-type stars younger than 300 Myr on galactic scales in M31. Based on the stellar photometric catalogs of the Panchromatic Hubble Andromeda Tre…

astro-ph.CO2011

The M81 Group Dwarf Irregular Galaxy DDO 165. I. High Velocity Neutral Gas in a Post-Starburst System

John M. Cannon, Hans P. Most, Evan D. Skillman +8

We present new multi-configuration VLA HI spectral line observations of the M81 group dIrr post-starburst galaxy DDO 165. The HI morphology is complex, with multiple column density…

astro-ph.GA2023

Composite Bulges -- III. A Study of Nuclear Star Clusters in Nearby Spiral Galaxies

Aishwarya Ashok, Anil Seth, Peter Erwin +17

We present photometric and morphological analyses of nuclear star clusters (NSCs) -- very dense, massive star clusters present in the central regions of most galaxies -- in a sampl…

cs.AI2020

Investigating the Scalability and Biological Plausibility of the Activation Relaxation Algorithm

Beren Millidge, Alexander Tschantz, Anil Seth +1

The recently proposed Activation Relaxation (AR) algorithm provides a simple and robust approach for approximating the backpropagation of error algorithm using only local learning…

astro-ph.GA2023

The Chemodynamics of the Stellar Populations in M31 from APOGEE Integrated Light Spectroscopy

Benjamin J. Gibson, Gail Zasowski, Anil Seth +8

We present analysis of nearly 1,000 near-infrared, integrated light spectra from APOGEE in the inner 7 kpc of M31. We utilize full spectrum fitting with A-LIST simple stellar…

astro-ph.GA2012

The Chandra View of NGC 4178: The Lowest Mass Black Hole in a Bulgeless Disk Galaxy?

Nathan Secrest, Shobita Satyapal, Mario Gliozzi +3

Using high resolution Chandra data, we report the presence of a weak X-ray point source coincident with the nucleus of NGC 4178, a late-type bulgeless disk galaxy known to have hig…

cs.AI2021

A Mathematical Walkthrough and Discussion of the Free Energy Principle

Beren Millidge, Anil Seth, Christopher L Buckley

The Free-Energy-Principle (FEP) is an influential and controversial theory which postulates a deep and powerful connection between the stochastic thermodynamics of self-organizatio…

astro-ph.GA2019

Astro2020 Science White Paper: Black Holes Across Cosmic Time

Kayhan Gültekin, Aaron Barth, Karl Gebhardt +8

Supermassive black holes are located at the center of most, if not all, massive galaxies. They follow close correlations with global properties of their host galaxies (scaling rela…

cs.NE2021

Neural Kalman Filtering

Beren Millidge, Alexander Tschantz, Anil Seth +1

The Kalman filter is a fundamental filtering algorithm that fuses noisy sensory data, a previous state estimate, and a dynamics model to produce a principled estimate of the curren…

astro-ph2002

Water Masers as Tracers of Protostellar Disks and Outflows in the Intermediate Mass Star Forming Region NGC 2071

Anil Seth, Lincoln Greenhill, Benjamin Holder

We have mapped the water maser emission associated with the infrared centers IRS1 and IRS3 of the NGC 2071IR star forming region at four epochs over ~4 months with the Very Long Ba…

astro-ph.HE2023

The black hole occupation fraction of local dwarf galaxies with AXIS

Elena Gallo, Edmund Hodges-Kluck, Tommaso Treu +7

The fraction of local dwarf galaxies that hosts massive black holes is arguably the cleanest diagnostic of the dominant seed formation mechanism of today's supermassive black holes…

astro-ph.GA2020

The APOGEE Library of Infrared SSP Templates (A-LIST): High-Resolution Simple Stellar Population Spectral Models in the H-Band

Aishwarya Ashok, Gail Zasowski, Anil Seth +8

Integrated light spectroscopy from galaxies can be used to study the stellar populations that cannot be resolved into individual stars. This analysis relies on stellar population s…