Survey of Ionized Gas of the Galaxy, Made with the Arecibo Telescope (SIGGMA): Inner Galaxy Data Release

Liu, Bin; McIntyre, Travis; Roshi, A.; Churchwell, E.; Minchin, R. F.; Terzian, Yervant

doi:10.3847/1538-4365/aaef8e

Cited by 30 publications

(25 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…• 5, b = −0. • 6 may be affected by W51 (compare Figure 4 with the radio recombination line map of W51 presented by Liu et al 2019). The case L = 100 pc then implies a mean n e B ≈ 10 µG cm −3 .…”

Section: Discussionmentioning

confidence: 89%

Strong Excess Faraday Rotation on the Inside of the Sagittarius Spiral Arm

Shanahan

Lemmer

Stil

et al. 2019

ApJL

Self Cite

View full text Add to dashboard Cite

We present first results for Faraday rotation of compact polarized sources (1 to 2 GHz continuum) in The HI/OH/Recombination line (THOR) survey of the inner Galaxy. In the Galactic longitude range 39 • < < 52 • , we find rotation measures in the range −310 rad m −2 ≤ RM ≤ +4219 rad m −2 , with the highest values concentrated within a degree of = 48 • at the Sagittarius arm tangent. Most of the high RM s arise in diffuse plasma, along lines of sight that do not intersect H II regions. For > 49 • , RM drops off rapidly, while at < 47 • , the mean RM is higher with a larger standard deviation than at > 49 • . We attribute the RM structure to the compressed diffuse Warm Ionized Medium in the spiral arm, upstream of the major star formation regions. The Sagittarius arm acts as a significant Faraday screen inside the Galaxy. This has implications for models of the Galactic magnetic field and the expected amount of Faraday rotation of Fast Radio Bursts from their host galaxies. We emphasize the importance of sensitivity to high Faraday depth in future polarization surveys.

show abstract

Section: Discussionmentioning

confidence: 89%

Strong Excess Faraday Rotation on the Inside of the Sagittarius Spiral Arm

Shanahan

Lemmer

Stil

et al. 2019

ApJL

Self Cite

View full text Add to dashboard Cite

show abstract

“…Wenger et al (2013 also studied the properties of helium and carbon RRL emission from the HRDS nebulae (including the H ii region G018.937−0.434a). Concerning the source G018.937−0.434a, line widths of hydrogen and helium lines were reported to be 23.83±0.05 and 16.31±0.85 km s −1 , respectively (Wenger et al 2013), which are smaller than the ones observed in supernova remnants (SNRs; i.e., > 50 km s −1 ; Liu et al 2019). Based on the properties of RRL emission (i.e., the 4 He + /H + ionic abundance ratio and line widths), the G18.937−0.434 (or G018.937−0.434a) was classified as a Galactic H ii region.…”

Section: Overview Of G1888−049mentioning

confidence: 95%

New Insights into the H ii Region G18.88–0.49: Hub–Filament System and Accreting Filaments

Dewangan

Ojha

Sharma

et al. 2020

ApJ

View full text Add to dashboard Cite

We present an analysis of multi-wavelength observations of an area of 0 • .27 × 0 • .27 around the Galactic H ii region G18.88−0.49, which is powered by an O-type star (age ∼10 5 years). The Herschel column density map reveals a shell-like feature of extension ∼12 pc × 7 pc and mass ∼2.9 ×10 4 M around the H ii region; its existence is further confirmed by the distribution of molecular ( 12 CO, 13 CO, C 18 O, and NH 3 ) gas at [60, 70] km s −1 . Four subregions are studied toward this shell-like feature, and show a mass range of ∼0.8-10.5 ×10 3 M . These subregions associated with dense gas are dominated by non-thermal pressure and supersonic non-thermal motions. The shell-like feature is associated with the H ii region, Class I protostars, and a massive protostar candidate, illustrating the ongoing early phases of star formation (including massive stars). The massive protostar is found toward the position of the 6.7 GHz methanol maser, and is associated with outflow activity. Five parsec-scale filaments are identified in the column density and molecular maps, and appear to be radially directed to the dense parts of the shell-like feature. This configuration is referred to as a "hub-filament" system. Significant velocity gradients (0.8-1.8 km s −1 pc −1 ) are observed along each filament, suggesting that the molecular gas flows towards the central hub along the filaments. Overall, our observational findings favor a global non-isotropic collapse scenario as discussed in Motte et al. (2018), which can explain the observed morphology and star formation in and around G18.88−0.49.

show abstract

“…as G051.010+00.060 (Anderson et al 2014;Liu et al 2019), which is a source of thermal radio continuum emission.…”

Section: Arayamentioning

confidence: 99%

GeV Emission in the Region of the Supernova Remnant G51.26+0.11

Araya

2021

ApJ

View full text Add to dashboard Cite

The supernova remnant (SNR) G51.26+0.11 was recently discovered and little is known about its properties and environment. Using data from the Fermi Large Area Telescope we study the GeV emission seen in the direction of G51.26+0.11 to constrain the origin of the gamma rays and their possible relation to this SNR or to a star-forming region. We also search for emission from molecular gas in the region that could provide dense material for the production of gamma rays. By modeling the multi-wavelength spectrum of G51.26+0.11 from radio to gamma rays we derive the properties of the particle populations that could produce the emission in several possible scenarios. We rule out the star-forming regions (such as G051.010+00.060) seen nearby as the origin of the GeV emission.The correspondence seen between the gamma-ray and radio morphologies support a scenario where G51.26+0.11 is the cause of the gamma rays. The flat spectral energy distribution observed at GeV energies is best fit by hadronic or inverse Compton emission, while a bremsstrahlung model cannot properly account for the radio fluxes under a simple one-zone scenario. A pulsar wind nebula origin of the high-energy photons cannot be ruled out or confirmed.

show abstract

Survey of Ionized Gas of the Galaxy, Made with the Arecibo Telescope (SIGGMA): Inner Galaxy Data Release

Cited by 30 publications

References 72 publications

Strong Excess Faraday Rotation on the Inside of the Sagittarius Spiral Arm

Strong Excess Faraday Rotation on the Inside of the Sagittarius Spiral Arm

New Insights into the H ii Region G18.88–0.49: Hub–Filament System and Accreting Filaments

GeV Emission in the Region of the Supernova Remnant G51.26+0.11

Contact Info

Product

Resources

About