High-precision millimeter-wave spectroscopy with the lamb dip

Winton, R. Scott; Gordy, Walter

doi:10.1016/0375-9601(70)90287-2

Cited by 86 publications

(28 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(Additional) transition frequencies in the range of our survey were contributed by Dubrulle et al (1980) for all species, by Winton & Gordy (1970) and van Dijk & Dymanus (1974) for the main isotopologue in its ground vibrational state, and by Larsen & Winnewisser (1974) for the 13 C isotopologue and for 2 = 1 of the main species.…”

Section: Carbonyl Sulfide Ocsmentioning

confidence: 69%

Complex organic molecules in the interstellar medium: IRAM 30 m line survey of Sagittarius B2(N) and (M)

Беллоче

Müller

Menten

et al. 2013

A&A

374

521

View full text Add to dashboard Cite

Context. The discovery of amino acids in meteorites fallen to Earth and the detection of glycine, the simplest of them, in samples returned from a comet to Earth strongly suggest that the chemistry of the interstellar medium is capable of producing such complex organic molecules and that they may be widespread in our Galaxy. Aims. Our goal is to investigate the degree of chemical complexity that can be reached in the interstellar medium, in particular in dense star-forming regions. Methods. We performed an unbiased, spectral line survey toward Sgr B2(N) and (M), two regions where high-mass stars are formed, with the IRAM 30 m telescope in the 3 mm atmospheric transmission window. Partial surveys at 2 and 1.3 mm were performed in parallel. The spectra were analyzed with a simple radiative transfer model that assumes local thermodynamic equilibrium but takes optical depth effects into account. Results. About 3675 and 945 spectral lines with a peak signal-to-noise ratio higher than 4 are detected at 3 mm toward Sgr B2(N) and (M), i.e. about 102 and 26 lines per GHz, respectively. This represents an increase by about a factor of two over previous surveys of Sgr B2. About 70% and 47% of the lines detected toward Sgr B2(N) and (M) are identified and assigned to 56 and 46 distinct molecules as well as to 66 and 54 less abundant isotopologues of these molecules, respectively. In addition, we report the detection of transitions from 59 and 24 catalog entries corresponding to vibrationally or torsionally excited states of some of these molecules, respectively, up to a vibration energy of 1400 cm −1 (2000 K). Excitation temperatures and column densities were derived for each species but should be used with caution. The rotation temperatures of the detected complex molecules typically range from ∼50 to 200 K. Among the detected molecules, aminoacetonitrile, n-propyl cyanide, and ethyl formate were reported for the first time in space based on this survey, as were five rare isotopologues of vinyl cyanide, cyanoacetylene, and hydrogen cyanide. We also report the detection of transitions from within twelve new vibrationally or torsionally excited states of known molecules. Absorption features produced by diffuse clouds along the line of sight are detected in transitions with low rotation quantum numbers of many simple molecules and are modeled with ∼30-40 velocity components with typical linewidths of ∼3-5 km s −1 . Conclusions. Although the large number of unidentified lines may still allow future identification of new molecules, we expect most of these lines to belong to vibrationally or torsionally excited states or to rare isotopologues of known molecules for which spectroscopic predictions are currently missing. Significant progress in extending the inventory of complex organic molecules in Sgr B2(N) and deriving tighter constraints on their location, origin, and abundance is expected in the near future thanks to an ongoing spectral line survey at 3 mm with ALMA in its cycles 0 and 1. The present single-dish surve...

show abstract

Section: Carbonyl Sulfide Ocsmentioning

confidence: 69%

Complex organic molecules in the interstellar medium: IRAM 30 m line survey of Sagittarius B2(N) and (M)

Беллоче

Müller

Menten

et al. 2013

A&A

374

521

View full text Add to dashboard Cite

show abstract

“…This very low pressure regime, the double-pass arrangement, and proper source power allowed the detection of a Lamb-dip spectrum (Costain 1969;Winton & Gordy 1970), whose high resolution is shown in the magnified windows of Fig. 1, where splittings of ∼30 kHz are well resolved.…”

Section: Experimental Details and Spectra Analysismentioning

confidence: 98%

The hyperfine structure of the inversion-rotation transitionJ_K= ${1}_{0}$ $\leftarrow$ ${0}_{0}$ of NH₃investigated by Lamb-dip spectroscopy

Cazzoli

Dore

Puzzarini

2009

A&A

View full text Add to dashboard Cite

The ground-state inversion-rotation transition of ammonia at 572.498 GHz has been investigated in the laboratory using a sourcemodulation microwave spectrometer equipped with a double-pass cell. The experiment has been carried out at a pressure lower than 0.5 mTorr, thus enabling to record a Lamb-dip spectrum showing a partial resolution of the magnetic hyperfine structure due to the three proton spins. The achieved high resolution proved to be comparable to that of molecular beam experiments. This measurement provides very precise rest frequencies of the J K = 1 0 ← 0 0 transition and of its hyperfine components, which fall in a spectral region covered by the HIFI instrument on board the Herschel satellite.

show abstract

“…A way to improve the accuracy of the retrieved frequencies has to exploit sub-Doppler resolution, which can be obtained by means of the Lamb-dip technique [133,134] in case of rotational spectroscopy. Despite the fast growth undergone by spectroscopy and non-linear optics in the past decade, the achievement of sub-Doppler resolution is only at its beginning.…”

Section: High-resolution Spectroscopymentioning

confidence: 99%

Terahertz Frequency Metrology for Spectroscopic Applications: a Review

Consolino

Bartalini

Natale

2017

J Infrared Milli Terahz Waves

View full text Add to dashboard Cite

We provide an overview on terahertz (THz) frequency metrology, starting from the nowadays available continuous wave THz sources, discussing their main features such as tunability, spectral purity, and frequency referencing to the primary frequency standards. A comparison on the achieved results in high-precision molecular spectroscopy is given and discussed, and finally, a special emphasis poses on the future developments of this upcoming field.

show abstract

High-precision millimeter-wave spectroscopy with the lamb dip

Cited by 86 publications

References 3 publications

Complex organic molecules in the interstellar medium: IRAM 30 m line survey of Sagittarius B2(N) and (M)

Complex organic molecules in the interstellar medium: IRAM 30 m line survey of Sagittarius B2(N) and (M)

The hyperfine structure of the inversion-rotation transitionJ_K= ${1}_{0}$ $\leftarrow$ ${0}_{0}$ of NH₃investigated by Lamb-dip spectroscopy

Terahertz Frequency Metrology for Spectroscopic Applications: a Review

Contact Info

Product

Resources

About

High-precision millimeter-wave spectroscopy with the lamb dip

Cited by 86 publications

References 3 publications

Complex organic molecules in the interstellar medium: IRAM 30 m line survey of Sagittarius B2(N) and (M)

Complex organic molecules in the interstellar medium: IRAM 30 m line survey of Sagittarius B2(N) and (M)

The hyperfine structure of the inversion-rotation transitionJK= ${1}_{0}$ $\leftarrow$ ${0}_{0}$ of NH3investigated by Lamb-dip spectroscopy

Terahertz Frequency Metrology for Spectroscopic Applications: a Review

Contact Info

Product

Resources

About

The hyperfine structure of the inversion-rotation transitionJ_K= ${1}_{0}$ $\leftarrow$ ${0}_{0}$ of NH₃investigated by Lamb-dip spectroscopy