Tables of Radio-Frequency Recombination Lines

Lilley, A. E.; Palmer, Patrick

doi:10.1086/190172

Cited by 40 publications

(29 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…There are two recombination lines, H81β and He81β, at 23860.87 and 23870.59 MHz, respectively (Lilley, Palmer 1968). Their frequencies are close to that of the (3, 3) line (23870.129 MHz).…”

Section: Ortho-to-para Abundance Ratios Of Nh 3 In Ngc 253mentioning

confidence: 74%

Observations of Ammonia in External Galaxies I. NGC 253 and M 82

Takano

Nakai

Kawaguchi

2002

Publications of the Astronomical Society of Japan

View full text Add to dashboard Cite

The ammonia (J, K) = (1, 1), (2, 2), (3, 3), and (4, 4) transitions in the 23.7-24.1 GHz region were searched for in nearby galaxies, NGC 253 and M 82, to study the relation between the molecular abundances and physical conditions. The (1, 1), (2, 2), and (3, 3) emission lines were clearly detected in NGC 253, but no lines were found in M 82. In NGC 253 the shapes of the three emission lines were different from one another. The rotational temperatures obtained in NGC 253 were 17-50 K, depending on the velocity components. There are two main results: (1) The ortho-to-para abundance ratio was obtained in NGC 253 and found to be different depending on the velocity components. The ratio was about 1 for the velocity component where the (2, 2) line is detected. On the other hand, the ratio was more than 6 for another velocity component where the (2, 2) line is barely detected. This high ratio corresponds to an equilibration temperature of less than 8 K between ortho and para. (2) The abundance of NH 3 in NGC 253 was found to be about an order of magnitude larger than the upper limit in M 82. This result is an additional evidence for the different molecular abundances which were already reported between NGC 253 and M 82. In addition, the molecular abundances including NH 3 in nearby galaxies with rich molecular gas were compared, and we found that the molecular abundance in M 82 is systematically peculiar concerning the formation mechanisms of molecules. We discussed factors which cause such a peculiarity in M 82.

show abstract

Section: Ortho-to-para Abundance Ratios Of Nh 3 In Ngc 253mentioning

confidence: 74%

Observations of Ammonia in External Galaxies I. NGC 253 and M 82

Takano

Nakai

Kawaguchi

2002

Publications of the Astronomical Society of Japan

View full text Add to dashboard Cite

show abstract

“…In the case of a blended line due to fine and/or hyperfine structures, a frequency of the strongest component is listed. Frequencies of the recombination lines are taken from Lilley & Palmer (1968) and Towle et al (1996). Frequencies are taken from Lovas (2004).…”

Section: Discussionmentioning

confidence: 99%

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

Takano

Nakajima

Kohno

2019

Publications of the Astronomical Society of Japan

View full text Add to dashboard Cite

We present observational data of a molecular line survey toward the nearby galaxies NGC 1068, NGC 253, and IC 342 at the wavelengths of 3 mm (∼85-116 GHz) obtained with the Nobeyama 45 m radio telescope. In IC 342 the line survey with high spectral resolution at 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 to study the impacts of X-rays and ultraviolet radiation on molecular abundances. The survey was carried out with the resulting rms noise level of a few mK (T * A ). As a result we could obtain almost complete data of these galaxies at the 3 mm region: We detected 19-23 molecular species depending on the galaxies including several new detections (e.g., cyclic-C 3 H 2 in IC 342). We found that the intensities of HCN, CN, and HC 3 N relative to 13 CO are significantly strong in NGC 1068 compared to those in NGC 253 and IC 342. On the other hand, CH 3 CCH was not detected in NGC 1068. We obtained these results with the narrow beam (15 ′′ .2-19 ′′ .1) of the 45 m telescope among the single-dish telescopes, and in particular selectively observed the molecular gas close to the circumnuclear disk (CND) in NGC 1068. Our line intensities in NGC 1068 were compared to 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 obtained the line intensities and stringent constraints on the upper limit for the three galaxies with such narrow beam, and consequently, the data will be a basis for further observations with high spatial resolution.

show abstract

“…Table 5. Hydrogen n = 1 to n = 5 recombination lines in the range of HIPASS observations (Lilley & Palmer 1968) and their apparent H I velocities. We encourage other researchers to make use of this data base.…”

Section: Datamentioning

confidence: 98%

“…Velocity distribution of HIPASS galaxies after the second verification check, with labels corresponding to potential RFI frequencies (top) and hydrogen recombination frequencies (bottom). list of hydrogen n = 1 to n = 5 recombination lines appearing in the HIPASS velocity range is given in Table 5 (taken from Lilley & Palmer 1968) and plotted against the distribution of detections following the first two verification checks in Fig. 6).…”

Section: Recombination Linesmentioning

confidence: 99%

The HIPASS catalogue - I. Data presentation

Meyer

Zwaan

Webster

et al. 2004

Monthly Notices of the Royal Astronomical Society

541

481

View full text Add to dashboard Cite

The H I Parkes All-Sky Survey (HIPASS) catalogue forms the largest uniform catalogue of H I sources compiled to date, with 4315 sources identified purely by their H I content. The catalogue data comprise the southern region δ < + 2 • of HIPASS, the first blind H I survey to cover the entire southern sky. The rms noise for this survey is 13 mJy beam −1 and the velocity range is −1280 to 12 700 km s −1 . Data search, verification and parametrization methods are discussed along with a description of measured quantities. Full catalogue data are made available to the astronomical community including positions, velocities, velocity widths, integrated fluxes and peak flux densities. Also available are on-sky moment maps, position-velocity moment maps and spectra of catalogue sources. A number of local large-scale features are observed in the space distribution of sources, including the super-Galactic plane and the Local Void. Notably, large-scale structure is seen at low Galactic latitudes, a region normally obscured at optical wavelengths.

show abstract

Tables of Radio-Frequency Recombination Lines

Cited by 40 publications

References 0 publications

Observations of Ammonia in External Galaxies I. NGC 253 and M 82

Observations of Ammonia in External Galaxies I. NGC 253 and M 82

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

The HIPASS catalogue - I. Data presentation

Contact Info

Product

Resources

About