Stellar Initial Mass Function (IMF) Probed with Supernova Rates and Neutrino Background: Cosmic Average IMF Slope is $\simeq 2-3$ Similar to the Salpeter IMF

Abstract

The stellar initial mass function (IMF) is expressed by $\varphi (m)\propto m^{-\alpha }$ with the slope $\alpha$, and known as the poorly-constrained but very important function in studies of star and galaxy formation. There are no sensible observational constraints on the IMF slopes beyond Milky Way and nearby galaxies. Here we combine two sets of observational results, 1) cosmic densities of core-collapse supernova explosion (CCSNe) rates and 2) cosmic far ultraviolet radiation (and infrared re-radiation) densities, which are sensitive to massive ($\simeq 8-50{\mathrm{M}}_{\odot }$) and moderately massive ($\simeq 2.5-7{\mathrm{M}}_{\odot }$) stars, respectively, and constrain the IMF slope at $m>1{\mathrm{M}}_{\odot }$ with a freedom of redshift evolution. Although no redshift evolution is identified beyond the uncertainties, we find that the cosmic average IMF slope at $z=0$ is $\alpha =1.8-3.2$ at the 95 % confidence level that is comparable with the Salpeter IMF, $\alpha =2.35$, which marks the first constraint on the cosmic average IMF. We show a forecast for the Nancy Grace Roman Space Telescope supernova survey that will provide significantly strong constraints on the IMF slope with $\delta \alpha \simeq 0.5$ over $z=0-2$. Moreover, as for an independent IMF probe instead of 1), we suggest to use diffuse supernovae neutrino background (DSNB), relic neutrinos from CCSNe. We expect that the Hyper-Kamiokande neutrino observations over 20 years will improve the constraints on the IMF slope and the redshift evolution significantly better than those obtained today, if the systematic uncertainties of DSNB production physics are reduced in the future numerical simulations.

arXiv comment7 pages, 6 figures, published in ApJ

References in corpus (31)

• Galactic Stellar and Substellar Initial Mass Function
• On the variation of the Initial Mass Function
• Cosmic Star Formation History
• How Massive Single Stars End their Life
• The propagation of uncertainties in stellar population synthesis modeling I: The relevance of uncertain aspects of stellar evolution and the IMF to the derived physical properties of galaxies
• Relativistic Shapiro delay measurements of an extremely massive millisecond pulsar
• From filamentary clouds to prestellar cores to the stellar IMF: Initial highlights from the Herschel Gould Belt survey
• The propagation of uncertainties in stellar population synthesis modeling III: model calibration, comparison, and evaluation
• A Universal Stellar Initial Mass Function? A Critical Look at Variations
• Gravitational-wave constraints on the neutron-star-matter Equation of State
• Neutron-star radius constraints from GW170817 and future detections
• A Substantial Population of Low Mass Stars in Luminous Elliptical Galaxies
• The Stellar Initial Mass Function in Early-Type Galaxies From Absorption Line Spectroscopy. II. Results
• The galaxy stellar mass-star formation rate relation: Evidence for an evolving stellar initial mass function?
• The Aquila prestellar core population revealed by Herschel
• Constraints on a Universal IMF from UV to Near-IR Galaxy Luminosity Densities
• The Diffuse Supernova Neutrino Background
• The Formation and Destruction of Molecular Clouds and Galactic Star Formation
• Supernova Relic Neutrino Search at Super-Kamiokande
• Simulations of the WFIRST Supernova Survey and Forecasts of Cosmological Constraints
• The Stellar Initial Mass Function in Early-Type Galaxies from Absorption Line Spectroscopy. III. Radial Gradients
• Supernova Neutrino Light Curves and Spectra for Various Progenitor Stars: From Core Collapse to Proto-neutron Star Cooling
• Core-collapse supernovae missed by optical surveys
• Atmospheric neutrino results from Super-Kamiokande and Kamiokande - Evidence for nu_mu oscillations -
• The Extended Hubble Space Telescope Supernova Survey: The Rate of Core Collapse Supernovae to z~1
• Simulating Turbulence-aided Neutrino-driven Core-collapse Supernova Explosions in One Dimension
• Detectability of the Supernova Relic Neutrinos and Neutrino Oscillation
• Implications of a Temperature Dependent IMF I: Photometric Template Fitting
• The stellar initial mass function at 0.9<z<1.5
• Comparison of cosmological simulations and deep submillimetre galaxy surveys
• The Cosmic Microwave Background and the Stellar Initial Mass Function

Cited by in corpus (2)

• Diffuse Neutrino Flux Based on the Rates of Core-collapse Supernovae and Black Hole Formation Deduced from a Novel Galactic Chemical Evolution Model
• Impacts of Black-Hole-Forming Supernova Explosions on the Diffuse Neutrino Background