Searcharxiv⌕ Search
Home/Archive/arXiv

arXiv · astro-ph/9808274

Structure and Kinematics of the Interstellar Medium in front of SN1987A

J. Xu·A. P. S. Crotts
View original source ↗Read source document ↗Export metadata ↓

Abstract

High resolution (10 km/s) [N II] echelle spectra, sampled every 13 arcsec in a 6 arcmin by 6 arcmin region around SN1987A were obtained on the CTIO 4m telescope. The map shows a complicated velocity structure consistent with that reported previously for the interstellar medium. Three components, heliocentric velocity V_hel=265, 277 and 285 km/s are identified as N157C. The radius of this large superbubble was found to expand at 10 km/s, with a lifetime of 6 million years and a total energy of 3x10^51 ergs determined from its radius and velocity according to superbubble theory. The V_hel=235 km/s component corresponds to the near side of 600 pc giant superbubble reported earlier. This bubble is over 10 million years old, and has blown out of the LMC disk. Two other components, V_hel=255 and 245 km/s are identified as the inner major light echo ring (a double-shell structure) at about 130 pc in front of SN1987A. There are also two high velocity components, 300 and 313 km/s, which are possibly the far side of a superbubble in which SN1987A exploded. We also notice that there are two components at 269 and 301 km/s within 20 arcsec of SN1987A. These structures are probably due to the emission from the progenitor star's red supergiant wind. We find that the time it took the SN1987A progenitor to move to the current location 300 pc behind N157C is comparable to the age of N157C as well as that of the progenitor itself.

Explore related subjects

astro-ph

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

J. Xu, A. P. S. Crotts. 1998-09-02. Structure and Kinematics of the Interstellar Medium in front of SN1987A. https://doi.org/10.1086/306637

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2024

Deformation procedure for scalar fields in cosmology

This work offers an extension of the deformation procedure introduced in field theory to the case of standard cosmology in the presence of real scalar field in flat space-time. The procedure is shown to work for many models, which give rise to several different cosmic scenarios, evolving under the presence of first-order differential equations which solve the corresponding equations of motion very appropriately.

astro-ph↗
arXiv2023

Dark Energy is the Cosmological Quantum Vacuum Energy of Light Particles-The Axion and the Lightest Neutrino

We uncover the general mechanism producing the dark energy(DE). This is only based on well known quantum physics and cosmology. We show that the observed DE originates from the cosmological quantum vacuum of light particles which provides a continuous energy distribution able to reproduce the data. Bosons give positive contributions to the DE while fermions yield negative contributions. As usual in field theory, ultraviolet divergences are subtracted from the physical quantities. The subtractions respect the symmetries of the theory and we normalize the physical quantities to be zero for the Minkowski vacuum. The resulting finite contributions to the energy density and the pressure from the quantum vacuum grow as log a(t) where a(t) is the scale factor, while the particle contributions dilute as 1/a^3(t), as it must be for massive particles. The DE equation of state P = w(z)H turns to be w(z)<-1 with w(z) asymptotically reaching the value -1 from below.A scalar particle can produce the observed DE through its quantum cosmological vacuum provided:(i)its mass is of the order of 10^{-3} eV = 1 meV,(ii) it is very weakly coupled and (iii) it is stable on the time scale of the age of the universe. The axion vacuum thus appears as a natural candidate. The neutrino vacuum (especially the lightest mass eigenstate) can give negative contributions to the DE. We find that w(z=0) is slightly below -1 by an amount ranging from [-1.5 10^{-3}] to [-8 10^{-3}] and we predict the axion mass to be in the range between 4 and 5 meV. We find that the universe will expand in the future faster than the de Sitter universe, as an exponential in the square of the cosmic time. DE arises from the quantum vacua of light particles in FRW cosmological space time in an analogous way to the Casimir effect in Minkowski spacetime with non trivial boundaries.

astro-ph↗