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. (arXiv:1902.10868v1 [astro-ph.GA])
<a href="http://arxiv.org/find/astro-ph/1/au:+Takano_S/0/1/0/all/0/1">Shuro Takano</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Nakajima_T/0/1/0/all/0/1">Taku Nakajima</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kohno_K/0/1/0/all/0/1">Kotaro Kohno</a>
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
($sim$85–116 GHz) obtained with the Nobeyama 45 m radio telescope. In IC 342
the line survey with high spectral resolution at the 3 mm region was reported
for the first time. NGC 1068 is a nearby gas-rich galaxy with X-rays from an
active galactic nucleus (AGN), and NGC 253 and IC 342 are nearby gas-rich
galaxies with prototypical starbursts. These galaxies are useful to study the
impacts of X-rays and ultraviolet radiation on molecular abundances. The survey
was carried out with the resulting rms noise level of a few mK ($Trm{_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.
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
($sim$85–116 GHz) obtained with the Nobeyama 45 m radio telescope. In IC 342
the line survey with high spectral resolution at the 3 mm region was reported
for the first time. NGC 1068 is a nearby gas-rich galaxy with X-rays from an
active galactic nucleus (AGN), and NGC 253 and IC 342 are nearby gas-rich
galaxies with prototypical starbursts. These galaxies are useful to study the
impacts of X-rays and ultraviolet radiation on molecular abundances. The survey
was carried out with the resulting rms noise level of a few mK ($Trm{_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.
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