scholarly journals A molecular line survey toward the nearby galaxies NGC 1068, NGC 253, and IC 342 at 3 mm with the Nobeyama 45 m radio telescope: The data

2019 ◽  
Vol 71 (Supplement_1) ◽  
Author(s):  
Shuro Takano ◽  
Taku Nakajima ◽  
Kotaro Kohno
Keyword(s):  
Radio Telescope ◽  
High Spectral Resolution ◽  
X Rays ◽  
Narrow Beam ◽  
Molecular Line ◽  
Line Intensities ◽  
Nearby Galaxies ◽  
Ngc 1068 ◽  
Line Survey ◽  
Molecular Abundances

AbstractWe present observational data of a molecular line survey toward the nearby galaxies NGC 1068, NGC 253, and IC 342 at wavelengths of 3 mm (∼85–116 GHz) obtained with the Nobeyama 45 m radio telescope. Regarding IC 342, a line survey with high spectral resolution in the 3 mm region was reported for the first time. NGC 1068 is a nearby gas-rich galaxy with X-rays from an active galactic nucleus (AGN), and NGC 253 and IC 342 are nearby gas-rich galaxies with prototypical starbursts. These galaxies are useful for studying the impacts of X-rays and ultraviolet radiation on molecular abundances. The survey was carried out with a resulting rms noise level of a few mK ($T\rm {_A^*}$). As a result we could obtain almost complete data of these galaxies in the 3 mm region: we detected 19–23 molecular species, depending on the galaxies, including several new detections (e.g., cyclic-C3H2 in IC 342). We found that the intensities of HCN, CN, and HC3N relative to 13CO are significantly strong in NGC 1068 compared with those in NGC 253 and IC 342. On the other hand, CH3CCH was not detected in NGC 1068. We obtained these results with the narrow beam (${15{^{\prime\prime}_{.}}2}$–${19{^{\prime\prime}_{.}}1}$) of the 45 m telescope, among single-dish telescopes, and in particular selectively observed molecular gas close to the circumnuclear disk (CND) in NGC 1068. The present line intensities in NGC 1068 were compared with those obtained with the IRAM 30 m radio telescope already reported. As a result, the intensity ratio of each line was found to have information on the spatial distribution. Our observations revealed the line intensities and stringent constraints on the upper limit for the three galaxies with such a narrow beam; consequently, the present data will be a basis for further observations with high spatial resolution.

scholarly journals Molecular Line Observations Towards W58 and GL490

1992 ◽  
Vol 150 ◽  
pp. 225-226
Author(s):  
D.G. Roh ◽  
H.R. Kim ◽  
Y.C. Minh ◽  
B.R. Auh ◽  
B.C. Koo
Keyword(s):  
Radio Telescope ◽  
Spectral Resolution ◽  
High Spectral Resolution ◽  
Interstellar Molecules ◽  
Molecular Line ◽  
Star Forming ◽  
Star Forming Regions ◽  
Molecular Abundances

We observed 3 mm transitions of several interstellar molecules toward star-forming regions in W58 and GL490 using the 14 m Daeduk Radio Telescope (Korea). We derive molecular abundances for the“broad” components observed with a high spectral resolution, which could represent the abundances of outflowing materials.

scholarly journals An ALMA and ATCA Molecular Line Survey Toward Centaurus A

2012 ◽  
Vol 8 (S292) ◽  
pp. 251-251
Author(s):  
Jürgen Ott ◽  
Mark McCoy ◽  
David Meier
Keyword(s):  
Radio Galaxy ◽  
Molecular Absorption ◽  
Physical Processes ◽  
Molecular Line ◽  
Physical Conditions ◽  
Line Survey ◽  
Molecular Abundances ◽  
Excitation Conditions ◽  
Compact Array ◽  
Centaurus A

AbstractWe present Atacama Large Millimeter/submillimeter Array (ALMA) and Australia Telescope Compact Array (ATCA) data of molecular absorption lines toward the bright central core of the prominent, nearby (d ∼ 3.8 Mpc) radio galaxy Centaurus A, at 13, 7, 3, and 1mm wavelengths. The line of sight crosses the prominent dust lane and continues through the disk and eventually through gas that may be very close to the central supermassive black hole. The goal of our survey is to determine the physical conditions of the gas via analyses of molecular line tracers including molecular abundances and excitation conditions that are sensitive to changes in temperature, density, ionization, and shocks. This study allows us to derive the physical processes that are shaping each molecular environment.

scholarly journals Aλ = 3 mm molecular line survey of NGC 1068

2012 ◽  
Vol 549 ◽  
pp. A39 ◽  
Author(s):  
R. Aladro ◽  
S. Viti ◽  
E. Bayet ◽  
D. Riquelme ◽  
S. Martín ◽  
...  
Keyword(s):  
Molecular Line ◽  
Ngc 1068 ◽  
Line Survey

scholarly journals 0.8mm extragalactic surveys of nearby galaxies

2016 ◽  
Vol 11 (S321) ◽  
pp. 305-305
Author(s):  
Ilhuiyolitzin Villicaña-Pedraza ◽  
Sergio Martín ◽  
Jesus Martín-Pintado ◽  
Miguel Requena-Torres ◽  
Rolf Guesten ◽  
...  
Keyword(s):  
Galactic Center ◽  
Ionization Rate ◽  
X Rays ◽  
Stellar Nucleosynthesis ◽  
Atmospheric Window ◽  
Nearby Galaxies ◽  
Line Survey ◽  
Extragalactic Surveys ◽  
Fitting In ◽  
First Time

AbstractWe present the first submillimetric line survey of extragalactic sources carried out by APEX. The surveys cover the 0.8 mm atmospheric window from 270 to 370GHz toward NGC253, NGC4945 and Arp220. We found in NGC 253, 150 transitions of 26 molecules. For NGC 4945, 136 transitions of 24 molecules, and 64 transitions of 17 molecules for Arp 220. Column densities and rotation temperatures have been determinate using the Local Thermodinamical Equilibrium(LTE) line profile simulation and fitting in the MADCUBA IJ software. The differences found in ratios between the Galactic Center and the starburst galaxies NGC 4945 and NGC 253 suggest that the gas is less processed in the latter than in the Galactic Center. The high 18O/17O ratios in the galaxies NGC 4945 and NGC 253 suggest also material less processed in the nuclei of these galaxies than in the Galactic Center. This is consistent with the claim that 17O is a more representative primary product than 18O in stellar nucleosynthesis (Wilson and Rood 1994); Also, we did a Multitransitions study of H3O+ at 307GHz, 364GHz, 388GHz and 396GHz. From our non-LTE analysis of H3O+ in NGC253 with RADEX we found that the collisional excitation can not explain the observed intensity of the ortho 396 GHz line. Excitation by radiation from the dust in the Far-IR can roughly explain the observations if the H2 densities are relatively low. From the derived H3O+ column densities we conclude that the chemistry of this molecule is dominated by ionization produce by the starburst in NGC253 (UV radiation from the O stars) and Arp 220 (cosmic rays from the supernovae) and likely from the AGN in NGC4549 (X-rays ); Finally, we report, for the first time, the tentative detection of the molecular ion HCNH+ (precursor of HCN and HNC) toward a galaxy, NGC4945, abundance explain the claimed enhancement of HCN abundance in the AGN, due to the enhancement of the ionization rate by X-rays. The abundance is much larger than the Galactic center of the Milky Way.

scholarly journals Molecular line emission in NGC 1068 imaged with ALMA

2014 ◽  
Vol 570 ◽  
pp. A28 ◽  
Author(s):  
S. Viti ◽  
S. García-Burillo ◽  
A. Fuente ◽  
L. K. Hunt ◽  
A. Usero ◽  
...  
Keyword(s):  
Line Emission ◽  
Molecular Line ◽  
Ngc 1068

scholarly journals Formic acid above the Jungfraujoch during 1985–2007: observed variability, seasonality, but no long-term background evolution

2010 ◽  
Vol 10 (6) ◽  
pp. 14771-14814 ◽  
Author(s):  
R. Zander ◽  
P. Duchatelet ◽  
E. Mahieu ◽  
P. Demoulin ◽  
G. Roland ◽  
...  
Keyword(s):  
Formic Acid ◽  
High Spectral Resolution ◽  
Temperature Sensitive ◽  
Atmospheric Gases ◽  
Vertical Column ◽  
Line Intensities ◽  
Sigma Level ◽  
Remote Measurements ◽  
Remote Determination

Abstract. This paper reports on daytime total vertical column abundances of formic acid (HCOOH) above the Northern mid-latitude, high altitude Jungfraujoch station (Switzerland; 46.5° N, 8.0° E, 3580 m altitude). The columns were derived from the analysis of infrared solar observations regularly performed with high spectral resolution Fourier transform spectrometers during over 1537 days between September 1985 and September 2007. The investigation was based on the spectrometric fitting of five spectral intervals, one encompassing the HCOOH ν6 band Q branch at 1105 cm−1, and four additional ones allowing to optimally account for critical temperature-sensitive or timely changing interferences by other atmospheric gases, in particular HDO, CCl2F2 and CHClF2. The main results derived from the 22 yr long database indicate that the free tropospheric burden of HCOOH above the Jungfraujoch undergoes important short-term daytime variability, diurnal and seasonal modulations, inter-annual anomalies, but no statistically significant long-term background change at the 1-sigma level. A major progress in the remote determination of the atmospheric HCOOH columns reported here has resulted from the adoption of new, improved absolute spectral line intensities for the infrared ν6 band of trans-formic acid, resulting in retrieved free tropospheric loadings being about a factor two smaller than if derived with previous spectroscopic parameters. Implications of this significant change with regard to earlier remote measurements of atmospheric formic acid and comparison with relevant Northern mid-latitude in situ findings will be assessed critically. Sparse HCOOH model predictions will also be evoked.

Molecular Line Survey

2014 ◽  
pp. 1-6
Author(s):  
Brett A. McGuire ◽  
Anthony J. Remijan
Keyword(s):  
Molecular Line ◽  
Line Survey

The Limits of Resolution in X-Ray Microscopy

1997 ◽  
Vol 3 (S2) ◽  
pp. 1185-1186
Author(s):  
J. Maser ◽  
C. Jacobsen ◽  
S. Spector
Keyword(s):  
Near Field ◽  
High Spectral Resolution ◽  
X Rays ◽  
Thin Specimen ◽  
Selective Labeling ◽  
X Ray ◽  
Luminescent Probes ◽  
Electron Microscopes ◽  
Good Signal ◽  
Do So

In far-field microscopes, the spatial resolution is ultimately limited by the wavelength of the radiation used. While near-field and related microscopes can improve upon this, they can only do so with thin specimen regions. Thin specimens can also be studied at atomic resolution using electron microscopes. To achieve improved resolution on micrometer-thick specimens, another alternative is to use significantly shorter photon wavelengths. We discuss here the use of soft x-rays for microscopy and their resolution limits.Image formation requires resolution and contrast. by using soft x-rays with a photon energy between the K absorption edges of carbon and oxygen, one is able to image hydrated biological specimens with high contrast. The contrast is such that no addi-tional staining is required, while efforts are also underway to utilize gold and luminescent probes for selective labeling. In addition, x-ray sources have high spectral resolution and good signal-to-background relative to electron microscopes which allows for elemental and chemical state mapping of major constituents.

scholarly journals Molecular line survey of the high-mass star-forming region NGC 6334I withHerschel/HIFI and the Submillimeter Array

2012 ◽  
Vol 546 ◽  
pp. A87 ◽  
Author(s):  
A. Zernickel ◽  
P. Schilke ◽  
A. Schmiedeke ◽  
D. C. Lis ◽  
C. L. Brogan ◽  
...  
Keyword(s):  
High Mass ◽  
Mass Star ◽  
Molecular Line ◽  
Star Forming ◽  
Line Survey
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