English
Related papers

Related papers: Magnetic fields and the location of the PDR

200 papers

The {\em B}-field Orion Protostellar Survey (BOPS) recently obtained polarimetric observations at 870 ${\rm \mu m}$ towards 61 protostars in the Orion molecular clouds with $\sim 1^{\prime\prime}$ spatial resolution using the Atacama Large…

A high density portion of the Orion Molecular Cloud 1 (OMC-1) contains the prominent, warm Kleinmann-Low (KL) nebula that is internally powered by an energetic event plus a farther region in which intermediate to high mass stars are…

Astrophysics of Galaxies · Physics 2015-06-03 T. -C. Peng , F. Wyrowski , L. A. Zapata , R. Güsten , K. M. Menten

The atomic-to-molecular hydrogen (H/H2) transition has been extensively studied as it controls the fraction of gas in a molecular state in an interstellar cloud. This fraction is linked to star-formation by the Schmidt-Kennicutt law. While…

Astrophysics of Galaxies · Physics 2021-12-08 Vincent Maillard , Emeric Bron , Franck Le Petit

Dust polarization observations are a powerful, practical tool to probe the geometry (and to some extent, the strength) of magnetic fields in star-forming regions. In particular, Planck polarization data have revealed the importance of…

A group of four compact HII regions associated with the well-known 50 km/s molecular cloud is the closest site of on-going star formation to the dynamical center of the Galaxy, at a projected distance of ~6 pc. We present a study of ionized…

Astrophysics of Galaxies · Physics 2015-05-20 F. Yusef-Zadeh , J. H. Lacy , M. Wardle , B. Whitney , H. Bushouse , D. A. Roberts , R. G. Arendt

We have studied the polarization characteristics and Faraday rotation of the extragalactic radio source J17204$-$3554, that appears projected on the north lobe of the galactic H II region NGC 6334A. From observations made with the Very…

Astrophysics of Galaxies · Physics 2015-05-30 L. F. Rodriguez , Y. Gomez , D. Tafoya

Photodissociation regions (PDRs) and shocks give rise to conspicuous emission from rotationally and vibrationally excited molecular hydrogen. This line emission has now been studied with ISO and from the ground in great detail. A remarkable…

We analyze the distribution of the interstellar matter in the environs of the \hii region Gum 31, excited by the open cluster NGC 3324, located in the complex Carina region, with the aim of investigating the action of the massive stars on…

Astrophysics · Physics 2007-07-16 C. Cappa , V. S. Niemela , R. Amorin , J. Vasquez , ;

Interstellar bubbles around O stars are driven by a combination of the star's wind and ionizing radiation output. The wind contribution is uncertain because the boundary between the wind and interstellar medium is difficult to observe.…

Astrophysics of Galaxies · Physics 2014-12-10 Jonathan Mackey , Vasilii V. Gvaramadze , Shazrene Mohamed , Norbert Langer

We study the large-scale magnetic field structure and its interplay with the gas dynamics in the Monoceros OB1 East molecular cloud. We combine observations of dust polarised emission from the Planck telescope and CO molecular line emission…

Astrophysics of Galaxies · Physics 2022-03-14 D. Alina , J. Montillaud , Y. Hu , A. Lazarian , I. Ristorcelli , E. Abdikamalov , S. Sagynbayeva , M. Juvela , T. Liu , J. -S. Carrière

We study the correlation of the velocity dispersion of the coexisting molecules H13CN and H13CO+ and the turbulent energy dissipation scale in the DR21(OH) star-forming region. The down-shift of the H13CO+ spectrum relative to H13CN is…

Astrophysics of Galaxies · Physics 2019-01-30 Talayeh Hezareh , Martin Houde , Carolyn McCoey , Hua-bai Li

Radio continuum observations of barred galaxies revealed strong magnetic fields of >= 50-100 muG in the circumnuclear starbursts. Such fields are dynamically important and give rise to magnetic stress that causes inflow of gas towards the…

Astrophysics of Galaxies · Physics 2015-06-03 Rainer Beck

We present ALMA Band 7 polarisation observations of the OMC-1 region of the Orion molecular cloud. We find that the polarisation pattern observed in the region is likely to have been significantly altered by the radiation field of the…

We report millimeter interferometric observations of polarized continuum and line emission from the massive star forming region G34.4. Polarized thermal dust emission at 3 mm wavelength and CO $J=1 \to 0$ line emission were observed using…

Astrophysics · Physics 2009-11-13 P. C. Cortes , R. M. Crutcher , D. Shepherd , L. Bronfman

Sharpless 2-27 (Sh2-27) is a nearby ${\rm H\,{\small II}}$ region excited by $\zeta$Oph. We present observations of polarized radio emission from 300 to 480$\,$MHz towards Sh2-27, made with the Parkes 64$\,$m Radio Telescope as part of the…

Magnetism is one of the most important forces on the interstellar medium (ISM), anisotropically regulating the structure and star formation that drive galactic evolution. Recent high dynamic range observations of diffuse gas and molecular…

Astrophysics of Galaxies · Physics 2019-03-20 S. E. Clark , Carl Heiles , Tim Robishaw

Because of their relatively simple morphology, "bubble" HII regions have been instrumental to our understanding of star formation triggered by HII regions. With the far-infrared (FIR) spectral coverage of the Herschel satellite, we can…

Spiral galaxies host dynamically important magnetic fields which can affect gas flows in the disks and halos. Total magnetic fields in spiral galaxies are strongest (up to 30 \muG) in the spiral arms where they are mostly turbulent or…

Astrophysics · Physics 2009-06-23 Rainer Beck

Interstellar magnetic fields are strong: up to 25 muG in spiral arms and 40 muG in nuclear regions. In the spiral galaxy NGC 6946 the average magnetic energy density exceeds that of the thermal gas. Magnetic fields control the evolution of…

Astrophysics · Physics 2017-01-25 Rainer Beck

We report Submillimeter Array dust continuum and molecular spectral line observations toward the Orion Bar photon-dominated region (PDR). The 1.2 mm continuum map reveals, for the first time, a total of 9 compact (r < 0.01pc) dust…

Solar and Stellar Astrophysics · Physics 2018-03-08 Keping Qiu , Zeqiang Xie , Qizhou Zhang