The Galactic Underworld: The spatial distribution of compact remnants

Abstract

We chart the expected Galactic distribution of neutron stars and black holes. These compact remnants of dead stars -- the Galactic underworld -- are found to exhibit a fundamentally different distribution and structure to the visible Galaxy. Compared to the visible Galaxy, concentration into a thin flattened disk structure is much less evident with the scale height more than tripling to 1260 +- 30 pc. This difference arises from two primary causes. Firstly, the distribution is in part inherited from the integration over the evolving structure of the Galaxy itself (and hence the changing distribution of the parent stars). Secondly, an even larger effect arises from the natal kick received by the remnant at the event of its supernova birth. Due to this kick we find 30% of remnants have sufficient kinetic energy to entirely escape the Galactic potential (40% of neutron stars and 2% of black holes) leading to a Galactic mass loss integrated to the present day of ~ 0.4% of the stellar mass of the Galaxy. The black hole -- neutron star fraction increases near the Galactic centre: a consequence of smaller kick velocities in the former (the assumption made is that kick velocity is inversely proportional to mass). Our simulated remnant distribution yields probable distances of 19 pc and 21 pc to the nearest neutron star and black hole respectively, while our nearest probable magnetar lies at 4.2 kpc. Although the underworld only contains of order ~ 1% of the Galaxy's mass, observational signatures and physical traces of its population, such as microlensing, will become increasingly present in data ranging from gravitational wave detectors to high precision surveys from space missions such as Gaia.

arXiv comment9 pages, 11 figures

References in corpus (71)

• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• Array Programming with NumPy
• GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral
• PARSEC: stellar tracks and isochrones with the PAdova and TRieste Stellar Evolution Code
• The ATNF Pulsar Catalogue
• How Massive Single Stars End their Life
• Binary interaction dominates the evolution of massive stars
• galpy: A Python Library for Galactic Dynamics
• A statistical study of 233 pulsar proper motions
• Stellar Multiplicity
• GW190521: A Binary Black Hole Merger with a Total Mass of $150M_{\odot }$
• Progenitors of core-collapse supernovae
• Explosion Mechanisms of Core-Collapse Supernovae
• Core-Collapse Supernovae from 9 to 120 Solar Masses Based on Neutrino-powered Explosions
• Compact Remnant Mass Function: Dependence on the Explosion Mechanism and Metallicity
• Magnetars
• Binary Black Hole Population Properties Inferred from the First and Second Observing Runs of Advanced LIGO and Advanced Virgo
• The McGill Magnetar Catalog
• Compact Object Modeling with the StarTrack Population Synthesis Code
• Black holes, gravitational waves and fundamental physics: a roadmap
• Birth and Evolution of Isolated Radio Pulsars
• The Black Hole Mass Distribution in the Galaxy
• Improving PARSEC models for very low mass stars
• PARSEC evolutionary tracks of massive stars up to $350M_{\odot }$ at metallicities 0.0001$\le Z\le$0.04
• Observational constraints on the progenitors of core-collapse supernovae : the case for missing high mass stars
• Binary and Millisecond Pulsars
• The Velocity Distribution of Isolated Radio Pulsars
• Be/X-ray binaries
• Mass Limits For Black Hole Formation
• New PARSEC evolutionary tracks of massive stars at low metallicity: testing canonical stellar evolution in nearby star forming dwarf galaxies
• Progenitor-Explosion Connection and Remnant Birth Masses for Neutrino-Driven Supernovae of Iron-Core Progenitors
• The Evolution of Compact Binary Star Systems
• Perspectives on Core-Collapse Supernova Theory
• A two-parameter criterion for classifying the explodability of massive stars by the neutrino-driven mechanism
• The Pulsar Kick Velocity Distribution
• Merging black hole binaries in galactic nuclei: implications for advanced-LIGO detections
• The Milky Way total mass profile as inferred from Gaia DR2
• On the Mass Distribution and Birth Masses of Neutron Stars
• Galaxia: a code to generate a synthetic survey of the Milky Way
• The search for failed supernovae with the Large Binocular Telescope: confirmation of a disappearing star
• On the formation history of Galactic double neutron stars
• Massive runaways and walkaway stars
• Investigating stellar-mass black hole kicks
• The Status of Multi-Dimensional Core-Collapse Supernova Models
• The observed velocity distribution of young pulsars
• Hydrodynamics of core-collapse supernovae and their progenitors
• Black Hole, Neutron Star and White Dwarf Candidates from Microlensing with OGLE-III
• Pre-supernova evolution, compact object masses and explosion properties of stripped binary stars
• An isolated mass gap black hole or neutron star detected with astrometric microlensing
• Formation of Double Neutron Star systems as implied by observations
• The Dawes Review 8: Measuring the Stellar Initial Mass Function
• Kinematic modelling of the Milky Way using the RAVE and GCS stellar surveys
• Simple recipes for compact remnant masses and natal kicks
• Constraining the masses of microlensing black holes and the mass gap with Gaia DR2
• The Galactic distribution of X-ray binaries and its implications for compact object formation and natal kicks
• Predicting the binary black hole population of the Milky Way with cosmological simulations
• The Formation of Supermassive Black Holes from Low-Mass Pop III Seeds
• Initial spin periods of neutron stars in supernova remnants
• Synthetic catalog of black holes in the Milky Way
• The observed velocity distribution of young pulsars II: analysis of complete PSR$\pi$
• Intermediate-Mass-Elements in Young Supernova Remnants Reveal Neutron Star Kicks by Asymmetric Explosions
• Detecting Black Hole Binaries by Gaia
• The most massive progenitors of neutron stars: CXO J164710.2-455216
• Combined analysis of neutron star natal kicks using proper motions and parallax measurements for radio pulsars and Be X-ray binaries
• The role of core-collapse physics in the observability of black-hole neutron-star mergers as multi-messenger sources
• X-ray emission from isolated neutron stars
• Evidence from high mass X-ray binaries that Galactic WR components of WR+O binaries end their life with a supernova explosion
• Suzaku Studies of the Supernova Remnant CTB~109 Hosting the Magnetar 1E~2259+586
• Pulsar spin-velocity alignment from single and binary neutron star progenitors
• Can Isolated Single Black Holes Produce X-ray Novae?
• Consequences of Energetic Magnetar-Like Outbursts of Nearby Neutron Stars: ${}^{14}$C Events and the Cosmic Electron Spectrum

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