University of Hertfordshire

From the same journal

From the same journal

Molecular gas kinematics within the central 250 pc of the Milky Way

Research output: Contribution to journalArticlepeer-review

Standard

Molecular gas kinematics within the central 250 pc of the Milky Way. / Henshaw, J.~D.; Longmore, S.~N.; Kruijssen, J.~M.~D.; Davies, B.; Bally, J.; Barnes, A.; Battersby, C.; Cunningham, M.~R.; Ginsburg, A.; Immer, K.; Jones, P.~A.; Kendrew, S.; Mills, E.~A.~C.; Molinari, S.; Moore, T.~J.~T.; Ott, J.; Pillai, T.; Rathborne, J.; Schilke, P.; Schmiedeke, A.; Testi, L.; Walker, D.; Walsh, A.; Zhang, Q.; Dale, James.

In: Monthly Notices of the Royal Astronomical Society, Vol. 457, No. 3, 12.02.2016, p. 2675-2702.

Research output: Contribution to journalArticlepeer-review

Harvard

Henshaw, JD, Longmore, SN, Kruijssen, JMD, Davies, B, Bally, J, Barnes, A, Battersby, C, Cunningham, MR, Ginsburg, A, Immer, K, Jones, PA, Kendrew, S, Mills, EAC, Molinari, S, Moore, TJT, Ott, J, Pillai, T, Rathborne, J, Schilke, P, Schmiedeke, A, Testi, L, Walker, D, Walsh, A, Zhang, Q & Dale, J 2016, 'Molecular gas kinematics within the central 250 pc of the Milky Way', Monthly Notices of the Royal Astronomical Society, vol. 457, no. 3, pp. 2675-2702. https://doi.org/10.1093/mnras/stw121

APA

Henshaw, J. D., Longmore, S. N., Kruijssen, J. M. D., Davies, B., Bally, J., Barnes, A., Battersby, C., Cunningham, M. R., Ginsburg, A., Immer, K., Jones, P. A., Kendrew, S., Mills, E. A. C., Molinari, S., Moore, T. J. T., Ott, J., Pillai, T., Rathborne, J., Schilke, P., ... Dale, J. (2016). Molecular gas kinematics within the central 250 pc of the Milky Way. Monthly Notices of the Royal Astronomical Society, 457(3), 2675-2702. https://doi.org/10.1093/mnras/stw121

Vancouver

Henshaw JD, Longmore SN, Kruijssen JMD, Davies B, Bally J, Barnes A et al. Molecular gas kinematics within the central 250 pc of the Milky Way. Monthly Notices of the Royal Astronomical Society. 2016 Feb 12;457(3):2675-2702. https://doi.org/10.1093/mnras/stw121

Author

Henshaw, J.~D. ; Longmore, S.~N. ; Kruijssen, J.~M.~D. ; Davies, B. ; Bally, J. ; Barnes, A. ; Battersby, C. ; Cunningham, M.~R. ; Ginsburg, A. ; Immer, K. ; Jones, P.~A. ; Kendrew, S. ; Mills, E.~A.~C. ; Molinari, S. ; Moore, T.~J.~T. ; Ott, J. ; Pillai, T. ; Rathborne, J. ; Schilke, P. ; Schmiedeke, A. ; Testi, L. ; Walker, D. ; Walsh, A. ; Zhang, Q. ; Dale, James. / Molecular gas kinematics within the central 250 pc of the Milky Way. In: Monthly Notices of the Royal Astronomical Society. 2016 ; Vol. 457, No. 3. pp. 2675-2702.

Bibtex

@article{2cfd295abe8d436a8afa10f744222540,
title = "Molecular gas kinematics within the central 250 pc of the Milky Way",
abstract = "Using spectral line observations of HNCO, N2H+, and HNC, we investigate the kinematics of dense gas in the central ∼250 pc of the Galaxy. We present SCOUSE (Semi-automated multi-COmponent Universal Spectral-line fitting Engine), a line-fitting algorithm designed to analyse large volumes of spectral line data efficiently and systematically. Unlike techniques which do not account for complex line profiles, SCOUSE accurately describes the {l, b, vLSR} distribution of Central Molecular Zone (CMZ) gas, which is asymmetric about Sgr A* in both position and velocity. Velocity dispersions range from 2.6 km s−1 < σ < 53.1 km s−1. A median dispersion of 9.8 km s−1, translates to a Mach number, M3D≥28. The gas is distributed throughout several {\textquoteleft}streams{\textquoteright}, with projected lengths ∼100–250 pc. We link the streams to individual clouds and sub-regions, including Sgr C, the 20 and 50 km s−1 clouds, the dust ridge, and Sgr B2. Shell-like emission features can be explained by the projection of independent molecular clouds in Sgr C and the newly identified conical profile of Sgr B2 in {l, b, vLSR} space. These features have previously invoked supernova-driven shells and cloud–cloud collisions as explanations. We instead caution against structure identification in velocity-integrated emission maps. Three geometries describing the 3D structure of the CMZ are investigated: (i) two spiral arms; (ii) a closed elliptical orbit; (iii) an open stream. While two spiral arms and an open stream qualitatively reproduce the gas distribution, the most recent parametrization of the closed elliptical orbit does not. Finally, we discuss how proper motion measurements of masers can distinguish between these geometries, and suggest that this effort should be focused on the 20 km s−1 and 50 km s−1 clouds and Sgr C.",
keywords = "stars: formation, ISM: clouds, ISM: kinematics and dynamics, ISM: structure, Galaxy: centre, galaxies: ISM",
author = "J.~D. Henshaw and S.~N. Longmore and J.~M.~D. Kruijssen and B. Davies and J. Bally and A. Barnes and C. Battersby and M.~R. Cunningham and A. Ginsburg and K. Immer and P.~A. Jones and S. Kendrew and E.~A.~C. Mills and S. Molinari and T.~J.~T. Moore and J. Ott and T. Pillai and J. Rathborne and P. Schilke and A. Schmiedeke and L. Testi and D. Walker and A. Walsh and Q. Zhang and James Dale",
note = "This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society. {\textcopyright}2016 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.",
year = "2016",
month = feb,
day = "12",
doi = "10.1093/mnras/stw121",
language = "English",
volume = "457",
pages = "2675--2702",
journal = "Monthly Notices of the Royal Astronomical Society",
issn = "0035-8711",
publisher = "Oxford University Press",
number = "3",

}

RIS

TY - JOUR

T1 - Molecular gas kinematics within the central 250 pc of the Milky Way

AU - Henshaw, J.~D.

AU - Longmore, S.~N.

AU - Kruijssen, J.~M.~D.

AU - Davies, B.

AU - Bally, J.

AU - Barnes, A.

AU - Battersby, C.

AU - Cunningham, M.~R.

AU - Ginsburg, A.

AU - Immer, K.

AU - Jones, P.~A.

AU - Kendrew, S.

AU - Mills, E.~A.~C.

AU - Molinari, S.

AU - Moore, T.~J.~T.

AU - Ott, J.

AU - Pillai, T.

AU - Rathborne, J.

AU - Schilke, P.

AU - Schmiedeke, A.

AU - Testi, L.

AU - Walker, D.

AU - Walsh, A.

AU - Zhang, Q.

AU - Dale, James

N1 - This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society. ©2016 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.

PY - 2016/2/12

Y1 - 2016/2/12

N2 - Using spectral line observations of HNCO, N2H+, and HNC, we investigate the kinematics of dense gas in the central ∼250 pc of the Galaxy. We present SCOUSE (Semi-automated multi-COmponent Universal Spectral-line fitting Engine), a line-fitting algorithm designed to analyse large volumes of spectral line data efficiently and systematically. Unlike techniques which do not account for complex line profiles, SCOUSE accurately describes the {l, b, vLSR} distribution of Central Molecular Zone (CMZ) gas, which is asymmetric about Sgr A* in both position and velocity. Velocity dispersions range from 2.6 km s−1 < σ < 53.1 km s−1. A median dispersion of 9.8 km s−1, translates to a Mach number, M3D≥28. The gas is distributed throughout several ‘streams’, with projected lengths ∼100–250 pc. We link the streams to individual clouds and sub-regions, including Sgr C, the 20 and 50 km s−1 clouds, the dust ridge, and Sgr B2. Shell-like emission features can be explained by the projection of independent molecular clouds in Sgr C and the newly identified conical profile of Sgr B2 in {l, b, vLSR} space. These features have previously invoked supernova-driven shells and cloud–cloud collisions as explanations. We instead caution against structure identification in velocity-integrated emission maps. Three geometries describing the 3D structure of the CMZ are investigated: (i) two spiral arms; (ii) a closed elliptical orbit; (iii) an open stream. While two spiral arms and an open stream qualitatively reproduce the gas distribution, the most recent parametrization of the closed elliptical orbit does not. Finally, we discuss how proper motion measurements of masers can distinguish between these geometries, and suggest that this effort should be focused on the 20 km s−1 and 50 km s−1 clouds and Sgr C.

AB - Using spectral line observations of HNCO, N2H+, and HNC, we investigate the kinematics of dense gas in the central ∼250 pc of the Galaxy. We present SCOUSE (Semi-automated multi-COmponent Universal Spectral-line fitting Engine), a line-fitting algorithm designed to analyse large volumes of spectral line data efficiently and systematically. Unlike techniques which do not account for complex line profiles, SCOUSE accurately describes the {l, b, vLSR} distribution of Central Molecular Zone (CMZ) gas, which is asymmetric about Sgr A* in both position and velocity. Velocity dispersions range from 2.6 km s−1 < σ < 53.1 km s−1. A median dispersion of 9.8 km s−1, translates to a Mach number, M3D≥28. The gas is distributed throughout several ‘streams’, with projected lengths ∼100–250 pc. We link the streams to individual clouds and sub-regions, including Sgr C, the 20 and 50 km s−1 clouds, the dust ridge, and Sgr B2. Shell-like emission features can be explained by the projection of independent molecular clouds in Sgr C and the newly identified conical profile of Sgr B2 in {l, b, vLSR} space. These features have previously invoked supernova-driven shells and cloud–cloud collisions as explanations. We instead caution against structure identification in velocity-integrated emission maps. Three geometries describing the 3D structure of the CMZ are investigated: (i) two spiral arms; (ii) a closed elliptical orbit; (iii) an open stream. While two spiral arms and an open stream qualitatively reproduce the gas distribution, the most recent parametrization of the closed elliptical orbit does not. Finally, we discuss how proper motion measurements of masers can distinguish between these geometries, and suggest that this effort should be focused on the 20 km s−1 and 50 km s−1 clouds and Sgr C.

KW - stars: formation, ISM: clouds, ISM: kinematics and dynamics, ISM: structure, Galaxy: centre, galaxies: ISM

U2 - 10.1093/mnras/stw121

DO - 10.1093/mnras/stw121

M3 - Article

VL - 457

SP - 2675

EP - 2702

JO - Monthly Notices of the Royal Astronomical Society

JF - Monthly Notices of the Royal Astronomical Society

SN - 0035-8711

IS - 3

ER -