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Register a new userThe Galactic Plane Infrared Polarization Survey (GPIPS): Data Release 4
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The Galactic Plane Infrared Polarization Survey (GPIPS) seeks to characterize the magnetic field in the dusty Galactic disk using near-infrared stellar polarimetry. All GPIPS observations were completed using the 1.83 m Perkins telescope and Mimir instrument. GPIPS observations surveyed 76 sq-deg of the northern Galactic plane, from Galactic longitudes 18 to 56 deg and latitudes -1 to +1 deg, in the H-band (1.6 um). Surveyed stars span 7th to 16th mag, resulting in nearly 10 million stars with measured linear polarizations. Of these stars, ones with m_H < 12.5 mag and polarization percentage uncertainties under 2% were judged to be high quality and number over one million. GPIPS data reveal plane-of-sky magnetic field orientations for numerous interstellar clouds for AV values to ~30 mag. The average sky separation of stars with m_H < 12.5 mag is about 30arcsec, or about 60 per Planck polarization resolution element. Matching to Gaia DR2 showed the brightest GPIPS stars are red giants with distances in the 0.6-7.5 kpc range. Polarization orientations are mostly parallel to the Galactic disk, with some zones showing significant orientation departures. Changes in orientations are stronger as a function of Galactic longitude than of latitude. Considered at 10 arcmin angular scales, directions that show the greatest polarization fractions and narrowest polarization position angle distributions are confined to about ten large, coherent structures that are not correlated with star forming clouds. The GPIPS polarimetric and photometric data products (Data Release 4 catalogs and images) are publicly available for over 13million stars.
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We present observations of fifty square degrees of the Mopra carbon monoxide (CO) survey of the Southern Galactic Plane, covering Galactic longitudes $l = 300$-$350^circ$ and latitudes $|b| le 0.5^circ$. These data have been taken at 0.6 arcminute spatial resolution and 0.1 km/s spectral resolution, providing an unprecedented view of the molecular clouds and gas of the Southern Galactic Plane in the 109-115 GHz $J = 1$-0 transitions of $^{12}$CO, $^{13}$CO, C$^{18}$O and C$^{17}$O. We present a series of velocity-integrated maps, spectra and position-velocity plots that illustrate Galactic arm structures and trace masses on the order of $sim$10$^{6}$ M$_{odot}$ per square degree; and include a preliminary catalogue of C$^{18}$O clumps located between $l=330$-$340^circ$. Together with information about the noise statistics of the survey these data can be retrieved from the Mopra CO website, the PASA data store and the Harvard Dataverse (doi:10.7910/DVN/LH3BDN ).
We present observations of the first ten degrees of longitude in the Mopra carbon monoxide (CO) survey of the southern Galactic plane (Burton et al. 2013), covering Galactic longitude l = 320-330{deg} and latitude b = $pm$0.5{deg}, and l = 327-330{deg}, b = +0.5-1.0{deg}. These data have been taken at 35 arc sec spatial resolution and 0.1 km/s spectral resolution, providing an unprecedented view of the molecular clouds and gas of the southern Galactic plane in the 109-115 GHz J = 1-0 transitions of 12CO, 13CO, C18O and C17O. Together with information about the noise statistics from the Mopra telescope, these data can be retrieved from the Mopra CO website and the CSIRO-ATNF data archive.
We have finished the 6cm polarization survey of the Galactic plane using the Urumqi 25m radio telescope. It covers 10deg<l<230deg in Galactic longitude and |b| <5deg in Galactic latitude. The new polarization maps not only reveal new properties of the diffuse magnetized interstellar medium, but also are very useful for studying individual objects such as Hii regions, which may act as Faraday screens with strong regular magnetic fields inside, and supernova remnants for their polarization properties and spectra. The high sensitivity of the survey enables us to discover two new SNRs G178.2-4.2 and G25.3-2.1 and a number of Hii regions.
The SEDIGISM (Structure, Excitation and Dynamics of the Inner Galactic Interstellar Medium) survey used the APEX telescope to map 84 deg^2 of the Galactic plane between l = -60 deg and l = +31 deg in several molecular transitions, including 13CO(2-1) and C18O(2-1), thus probing the moderately dense (~10^3 cm^-3) component of the interstellar medium. With an angular resolution of 30 and a typical 1-sigma sensitivity of 0.8-1.0 K at 0.25 km/s velocity resolution, it gives access to a wide range of structures, from individual star-forming clumps to giant molecular clouds and complexes. The coverage includes a good fraction of the first and fourth Galactic quadrants, allowing us to constrain the large scale distribution of cold molecular gas in the inner Galaxy. In this paper we provide an updated overview of the full survey and the data reduction procedures used. We also assess the quality of these data and describe the data products that are being made publicly available as part of this first data release (DR1). We present integrated maps and position-velocity maps of the molecular gas and use these to investigate the correlation between the molecular gas and the large scale structural features of the Milky Way such as the spiral arms, Galactic bar and Galactic centre. We find that approximately 60 per cent of the molecular gas is associated with the spiral arms and these appear as strong intensity peaks in the derived Galactocentric distribution. We also find strong peaks in intensity at specific longitudes that correspond to the Galactic centre and well known star forming complexes, revealing that the 13CO emission is concentrated in a small number of complexes rather than evenly distributed along spiral arms.
(Abridged) We present the first public release of high-quality data products (DR1) from Hi-GAL, the {em Herschel} infrared Galactic Plane Survey. Hi-GAL is the keystone of a suite of continuum Galactic Plane surveys from the near-IR to the radio, and covers five wavebands at 70, 160, 250, 350 and 500 micron, encompassing the peak of the spectral energy distribution of cold dust for 8 < T < 50K. This first Hi-GAL data release covers the inner Milky Way in the longitude range 68{deg} > l > -70{deg} in a |b|<1{deg} latitude strip. Photometric maps have been produced with the ROMAGAL pipeline, that optimally capitalizes on the excellent sensitivity and stability of the bolometer arrays of the {em Herschel} PACS and SPIRE photometric cameras, to deliver images of exquisite quality and dynamical range, absolutely calibrated with {em Planck} and {em IRAS}, and recovering extended emission at all wavelengths and all spatial scales. The compact source catalogues have been generated with the CuTEx algorithm, specifically developed to optimize source detection and extraction in the extreme conditions of intense and spatially varying background that are found in the Galactic Plane in the thermal infrared. Hi-GAL DR1 images will be accessible via a dedicated web-based image cutout service. The DR1 Compact Source Catalogues are delivered as single-band photometric lists containing, in addition to source position, peak and integrated flux and source sizes, a variety of parameters useful to assess the quality and reliability of the extracted sources, caveats and hints to help this assessment are provided. Flux completeness limits in all bands are determined from extensive synthetic source experiments and depend on the specific line of sight along the Galactic Plane. Hi-GAL DR1 catalogues contain 123210, 308509, 280685, 160972 and 85460 compact sources in the five bands, respectively.
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