Erratum

Collapse of a molecular cloud core to stellar densities: Stellar core and outflow formation in radiation magnetohydrodynamics simulations [MNRAS, 465, (2017) (2714-2716)] DOI: 10.1093/mnras/stt1865

Matthew R. Bate, Terrence S. Tricco, Daniel J. Price

Research output: Contribution to journalComment / DebateOtherpeer-review

Abstract

The paper 'Collapse of a molecular cloud core to stellar densities: stellar core and outflow formation in radiation magnetohydrodynamics simulations' was published in MNRAS, 437, 77 (2014) (hereafter 'the Original Paper'). The calculations presented in that work were performed using a smoothed particle magnetohydrodynamics code known as sphNG. Unfortunately, a bug was present in the integrator that was used to evolve the magnetic field. This necessitated the use of rapid divergence cleaning of the magnetic field (using a cleaning speed 30 times faster than the fast magnetohydrodynamics, MHD, wave speed) in the Original Paper in order to maintain stability of the calculations.We are grateful to Dobbs (private communication) for the discovery of the error in the integrator. In this erratum, we compare results from one of the original calculations with those obtained using a more recent version of the code in which the integrator has been corrected. In addition, the more recent code includes the improved divergence cleaning scheme of Tricco, Price & Bate (2016), though we have found that for this problem, the differences between calculations using the older cleaning scheme and those using the new scheme are insignificant. The corrected code uses the standard divergence cleaning wave speed (equal to the fast MHD wave speed). This allows larger timesteps to be taken, which results in the calculations running up to 30 times faster early on. However, after the stellar core forms, the calculations are only about four times faster because thermal and gravitational forces dominate over magnetic forces inside the stellar core.We show that the results of the calculations are slightly different, but these minor differences do not affect the conclusions in the Original Paper. Section 1 of this erratum discusses the integrator bug in detail and then in Section 2, we provide a side-by-side comparison of the calculation from the Original Paper that had the strongest magnetic field strength with a calculation using the more recent code that uses a corrected integrator and includes the improved divergence cleaning scheme.

Original languageEnglish
Pages (from-to)2714-2716
Number of pages3
JournalMonthly Notices of the Royal Astronomical Society
Volume465
Issue number3
DOIs
Publication statusPublished - 2017

Keywords

  • Accretion
  • Accretion discs
  • MHD
  • Outflows
  • Radiative transfer
  • Stars: evolution
  • Stars: formation
  • Stars: winds

Cite this

@article{5ae7ee38a9c74761a0f7ae5ab600e0bf,
title = "Erratum: Collapse of a molecular cloud core to stellar densities: Stellar core and outflow formation in radiation magnetohydrodynamics simulations [MNRAS, 465, (2017) (2714-2716)] DOI: 10.1093/mnras/stt1865",
abstract = "The paper 'Collapse of a molecular cloud core to stellar densities: stellar core and outflow formation in radiation magnetohydrodynamics simulations' was published in MNRAS, 437, 77 (2014) (hereafter 'the Original Paper'). The calculations presented in that work were performed using a smoothed particle magnetohydrodynamics code known as sphNG. Unfortunately, a bug was present in the integrator that was used to evolve the magnetic field. This necessitated the use of rapid divergence cleaning of the magnetic field (using a cleaning speed 30 times faster than the fast magnetohydrodynamics, MHD, wave speed) in the Original Paper in order to maintain stability of the calculations.We are grateful to Dobbs (private communication) for the discovery of the error in the integrator. In this erratum, we compare results from one of the original calculations with those obtained using a more recent version of the code in which the integrator has been corrected. In addition, the more recent code includes the improved divergence cleaning scheme of Tricco, Price & Bate (2016), though we have found that for this problem, the differences between calculations using the older cleaning scheme and those using the new scheme are insignificant. The corrected code uses the standard divergence cleaning wave speed (equal to the fast MHD wave speed). This allows larger timesteps to be taken, which results in the calculations running up to 30 times faster early on. However, after the stellar core forms, the calculations are only about four times faster because thermal and gravitational forces dominate over magnetic forces inside the stellar core.We show that the results of the calculations are slightly different, but these minor differences do not affect the conclusions in the Original Paper. Section 1 of this erratum discusses the integrator bug in detail and then in Section 2, we provide a side-by-side comparison of the calculation from the Original Paper that had the strongest magnetic field strength with a calculation using the more recent code that uses a corrected integrator and includes the improved divergence cleaning scheme.",
keywords = "Accretion, Accretion discs, MHD, Outflows, Radiative transfer, Stars: evolution, Stars: formation, Stars: winds",
author = "Bate, {Matthew R.} and Tricco, {Terrence S.} and Price, {Daniel J.}",
year = "2017",
doi = "10.1093/mnras/stw2940",
language = "English",
volume = "465",
pages = "2714--2716",
journal = "Monthly Notices of the Royal Astronomical Society",
issn = "0035-8711",
publisher = "Oxford University Press, USA",
number = "3",

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T1 - Erratum

T2 - Collapse of a molecular cloud core to stellar densities: Stellar core and outflow formation in radiation magnetohydrodynamics simulations [MNRAS, 465, (2017) (2714-2716)] DOI: 10.1093/mnras/stt1865

AU - Bate, Matthew R.

AU - Tricco, Terrence S.

AU - Price, Daniel J.

PY - 2017

Y1 - 2017

N2 - The paper 'Collapse of a molecular cloud core to stellar densities: stellar core and outflow formation in radiation magnetohydrodynamics simulations' was published in MNRAS, 437, 77 (2014) (hereafter 'the Original Paper'). The calculations presented in that work were performed using a smoothed particle magnetohydrodynamics code known as sphNG. Unfortunately, a bug was present in the integrator that was used to evolve the magnetic field. This necessitated the use of rapid divergence cleaning of the magnetic field (using a cleaning speed 30 times faster than the fast magnetohydrodynamics, MHD, wave speed) in the Original Paper in order to maintain stability of the calculations.We are grateful to Dobbs (private communication) for the discovery of the error in the integrator. In this erratum, we compare results from one of the original calculations with those obtained using a more recent version of the code in which the integrator has been corrected. In addition, the more recent code includes the improved divergence cleaning scheme of Tricco, Price & Bate (2016), though we have found that for this problem, the differences between calculations using the older cleaning scheme and those using the new scheme are insignificant. The corrected code uses the standard divergence cleaning wave speed (equal to the fast MHD wave speed). This allows larger timesteps to be taken, which results in the calculations running up to 30 times faster early on. However, after the stellar core forms, the calculations are only about four times faster because thermal and gravitational forces dominate over magnetic forces inside the stellar core.We show that the results of the calculations are slightly different, but these minor differences do not affect the conclusions in the Original Paper. Section 1 of this erratum discusses the integrator bug in detail and then in Section 2, we provide a side-by-side comparison of the calculation from the Original Paper that had the strongest magnetic field strength with a calculation using the more recent code that uses a corrected integrator and includes the improved divergence cleaning scheme.

AB - The paper 'Collapse of a molecular cloud core to stellar densities: stellar core and outflow formation in radiation magnetohydrodynamics simulations' was published in MNRAS, 437, 77 (2014) (hereafter 'the Original Paper'). The calculations presented in that work were performed using a smoothed particle magnetohydrodynamics code known as sphNG. Unfortunately, a bug was present in the integrator that was used to evolve the magnetic field. This necessitated the use of rapid divergence cleaning of the magnetic field (using a cleaning speed 30 times faster than the fast magnetohydrodynamics, MHD, wave speed) in the Original Paper in order to maintain stability of the calculations.We are grateful to Dobbs (private communication) for the discovery of the error in the integrator. In this erratum, we compare results from one of the original calculations with those obtained using a more recent version of the code in which the integrator has been corrected. In addition, the more recent code includes the improved divergence cleaning scheme of Tricco, Price & Bate (2016), though we have found that for this problem, the differences between calculations using the older cleaning scheme and those using the new scheme are insignificant. The corrected code uses the standard divergence cleaning wave speed (equal to the fast MHD wave speed). This allows larger timesteps to be taken, which results in the calculations running up to 30 times faster early on. However, after the stellar core forms, the calculations are only about four times faster because thermal and gravitational forces dominate over magnetic forces inside the stellar core.We show that the results of the calculations are slightly different, but these minor differences do not affect the conclusions in the Original Paper. Section 1 of this erratum discusses the integrator bug in detail and then in Section 2, we provide a side-by-side comparison of the calculation from the Original Paper that had the strongest magnetic field strength with a calculation using the more recent code that uses a corrected integrator and includes the improved divergence cleaning scheme.

KW - Accretion

KW - Accretion discs

KW - MHD

KW - Outflows

KW - Radiative transfer

KW - Stars: evolution

KW - Stars: formation

KW - Stars: winds

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U2 - 10.1093/mnras/stw2940

DO - 10.1093/mnras/stw2940

M3 - Comment / Debate

VL - 465

SP - 2714

EP - 2716

JO - Monthly Notices of the Royal Astronomical Society

JF - Monthly Notices of the Royal Astronomical Society

SN - 0035-8711

IS - 3

ER -