# H. S. P. Muller's research while affiliated with University of Cologne and other places

## Publications (41)

Preprint
This overview paper presents ATOMIUM, a Large Programme in Cycle 6 with the Atacama Large Millimeter-submillimeter Array (ALMA). The goal of ATOMIUM is to understand the dynamics and the gas phase and dust formation chemistry in the winds of evolved asymptotic giant branch (AGB) and red supergiant (RSG) stars. A more general aim is to identify chem...
Article
Context. Glycinamide (NH 2 CH 2 C(O)NH 2 ) is considered to be one of the possible precursors of the simplest amino acid, glycine. Its only rotational spectrum reported so far has been in the centimetre-wave region on a laser-ablation generated supersonic expansion sample. Aims. The aim of this work is to extend the laboratory spectrum of glycinami...
Preprint
The nebular circumstellar environments of cool evolved stars are known to harbour a rich morphological complexity of gaseous structures on different length scales. A large part of these density structures are thought to be brought about by the interaction of the stellar wind with a close companion. The S-type asymptotic giant branch star Pi1 Gruis,...
Article
Context. Aminoacetonitrile, a molecule detected in the interstellar medium only toward the star-forming region Sagittarius B2 (Sgr B2), is considered an important prebiotic species; in particular, it is a possible precursor of the simplest amino acid glycine. To date, observations have been limited to ground state emission lines, whereas transition...
Article
Full-text available
Nitrogen oxides are thought to play a significant role as a nitrogen reservoir and to potentially participate in the formation of more complex species. Until now, only NO, NO, and HNO have been detected in the interstellar medium. We report the first interstellar detection of nitrous acid (HONO). Twelve lines were identified towards component B of...
Article
Context. One of the important questions of astrochemistry is how complex organic molecules, including potential prebiotic species, are formed in the envelopes around embedded protostars. The abundances of minor isotopologues of a molecule, in particular the D- and ¹³ C-bearing variants, are sensitive to the densities, temperatures and timescales ch...
Article
We present results from a comprehensive submillimeter spectral survey toward the source Orion South, based on data obtained with the HIFI instrument aboard the Herschel Space Observatory, covering the frequency range 480 to 1900 GHz. We detect 685 spectral lines with S/N > 3σ, originating from 52 different molecular and atomic species. We model eac...
Article
Full-text available
Formamide (NH2CHO) has previously been detected in several star-forming regions and is thought to be a precursor for different prebiotic molecules. Its formation mechanism is still debated, however. Observations of formamide, related species, and their isopotologues may provide useful clues to the chemical pathways leading to their formation. The P...
Article
Full-text available
We present the first ∼7.'5 × 11.'5 velocity-resolved (∼0.2 km/s) map of the [C ii] 158 μm line toward the Orion molecular cloud 1 (OMC 1) taken with the Herschel/HIFI instrument. In combination with far-IR (FIR) photometric images and velocity-resolved maps of the H41α hydrogen recombination and CO J = 2–1 lines, this data set provides an unprecede...
Article
Full-text available
We report the first detection of pure rotational transitions of TiO and TiO_2 at (sub-)millimeter wavelengths towards the red supergiant VY CMa. A rotational temperature, T_rot, of about 250 K was derived for TiO_2. Although T_rot was not well constrained for TiO, it is likely somewhat higher than that of TiO_2. The detection of the Ti oxides confi...
Article
Full-text available
The formation of inorganic dust in circumstellar environments of evolved stars is poorly understood. Spectra of molecules thought to be most important for the nucleation, i.e. AlO, TiO, and TiO2, have been recently detected in the red supergiant VY CMa. These molecules are effectively formed in VY CMa and the observations suggest that non-equilibri...
Article
A spectrum of VY Canis Majoris obtained with the Plateau de Bure Interferometer on 22 April and 13 October 2012 in the frequency range 220.65-224.25GHz. The interferometer was used in its D configuration with six antennas and the synthesized beam was 4.9x2.2-arcsec. The spectrum was extracted from the central pixel of the map obtained with the grid...
Article
Circumstellar envelopes around late-type stars harbour a rich variety of molecular gas and copious amounts of dust, originating from the mass-loss of the central star during the asymptotic giant branch (AGB) or the red supergiant phase. The formation of dust in these objects, in particular the first nucleation stages out of gas phase molecules, is...
Article
Full-text available
We have used the Herschel-HIFI instrument to observe interstellar nitrogen hydrides along the sight-lines towards W49N and G10.6-0.4 in order to elucidate the production pathways leading to nitrogen-bearing species in diffuse gas. All detections show absorption by foreground material over a wide range of velocities, as well as absorption associated...
Article
Three conformers of n-butyl cyanide have been studied in this work, anti-anti (AA), gauche-anti (GA), and anti-gauche (AG). The molecules are asymmetric top rotors. 14N hyperfine structure has been observed in part in previous work. Watson's S-reduction was used in the representation Ir. Data below 22GHz are from previous work; data above 75GHz are...
Article
Full-text available
At the last meeting, we reported the preliminary results on an isotopically invariant Dunham-type fit of the six oxygen isotopologues including experimental data for $v=0-18$ in $X^{3}\Sigma^{-}_{g}$, $v=0-10$ in $a^{1}\Delta_{g}$, $v=0-12$ in $b^{1}\Sigma^{+}_{g}$. At this meeting we report the the results of our complete fit, with additional expe...
Article
A molecular line survey was carried out with the IRAM 30 m telecope toward the prolific hot core Sgr B2(N) in order to explore its molecular complexity. The entire 3 mm range as well as selected regions at 2 and 1.3 mm were covered. Notable results include the detections of aminoacetonitrile, ethyl formate, n-propyl cyanide, and the singly substitu...
Article
Full-text available
We have examined methanol emission from Orion KL with of the {\em Herschel}/HIFI instrument, and detected two methanol bands centered at 524 GHz and 1061 GHz. The 524 GHz methanol band (observed in HIFI band 1a) is dominated by the isolated $\Delta$J$=$0, K$=-4\rightarrow$-3, v$_t$$=$0 Q branch, and includes 25 E-type and 2 A-type transitions. The...
Article
Although water is just a simple triatomic molecule, its spectroscopy still remains a challenge due to the ever increasing amount of available data. Two types of data have been recently obtained for water: \\begin{itemize} \item Accurate frequencies have been measured for transitions in the sub millimeter and terahertz domains involving high-lying r...
Article
The major new facilities, Herschel, SOFIA and ALMA are opening up the submillimeter region by making investigations of unprecedented high sensitivity and angular resolution over a very wide wavelength range. To cope with the amount of data new methods are developed to analyse those spectra using the two major databases for molecular spectroscopy: t...
Article
Ethanol is a complex organic molecule (COM), observed principally in hot core regions in the interstellar medium (e.g. Sgr B2, W51M, Orion KL, G34.3+0.15). The 13C isotopologues have not been identified in the ISM and prior to this work only scarce low-frequency laboratory data were available. Absorption spectra of both 13C isotopologues of ethanol...
Article
A global fit of the six isotopologues of the O$_2$ molecule has been carried out, with the purpose to support the current and future Earth remote sensing missions. All previously available experimental data from the following systems were collected and used in the analysis: the microwave transitions in the $X^{3}\Sigma^{-}_{g}$ and $a^{1}\Delta_{g}... Article The rotational and rovibrational spectra of H$_2$O and its isotopologs, including HDO, are of great importance for atmospheric chemistry, astrophysics, and basic sciences. We recorded rotational spectra of HDO in the ground and first excited bending state from the microwave region up to 2.8~THz. Several spectrometers were employed in Kiel, Koln, an... Article Full-text available We present the first results of a high-spectral-resolution survey of the carbon-rich evolved star IRC+10216 that was carried out with the HIFI spectrometer onboard Herschel. This survey covers all HIFI bands, with a spectral range from 488 to 1901GHz. In this letter we focus on the band-1b spectrum, in a spectral range 554.5-636.5GHz, where we iden... Article Full-text available We report the detection of more than 48 velocity-resolved ground rotational state transitions of H2(16)O, H2(18)O, and H2(17)O - most for the first time - in both emission and absorption toward Orion KL using Herschel/HIFI. We show that a simple fit, constrained to match the known emission and absorption components along the line of sight, is in ex... Article Full-text available Aims. This paper describes the Heterodyne Instrument for the Far-Infrared ( HIFI) that was launched onboard ESA's Herschel Space Observatory in May 2009. Methods. The instrument is a set of 7 heterodyne receivers that are electronically tuneable, covering 480-1250 GHz with SIS mixers and the 1410-1910 GHz range with hot electron bolometer (HEB) mix... Article Dimethyl ether (CH3OCH3) is one of the largest or detected in the interstellar medium. As an asymmetric top molecule with two methyl groups which undergo large amplitude motions and a dipole moment of mub=1.3D it conveys a dense spectrum throughout the terahertz region and contributes to the spectral line confusion in astronomical observations at t... Conference Paper Titanium monoxide, TiO, is a well known astronomical molecule that exhibits prominent electronic absorption lines in the spectra of M and S stars. We present here improved rotational transition frequencies for an astronomical search in the radio band }. The recent laboratory detection of TiO$_2$in the cm-wave region and its tentative detection in... Article Vibrational satellites of spectral lines from a number of molecules have been found for several species in high-mass star-forming regions or in circumstellar envelopes around mass-losing evolved stars. To excite levels in high energy states and produce emission (or absorption) lines strong enough to be observable by radio or (sub)millimeter telesco... Article The method of laser-induced reaction} {\bf 127} (2007) Art. No. 154317.} has been used for the first time to detect rotational transitions. The astronomically important$1_{01} - 0_{00}$and$1_{11} - 0_{00}$transitions of H$_2$D$^+$and HD$_2^+\$, respectively, have been recorded by observing the enhancement of their D/H isotope exchange reactions...
Article
Full-text available
We discuss the first astronomical detection of the CF+ (fluoromethylidynium) ion, obtained by observations of the J=1-0 (102.6 GHz), J=2-1 (205.2 GHz) and J=3-2 (307.7 GHz) rotational transitions toward the Orion Bar region. Our search for CF+, carried out using the IRAM 30m and APEX 12m telescopes, was motivated by recent theoretical models that p...
Article
Full-text available
We report the first astronomical detection of the CF+ (fluoromethylidynium) ion obtained by recent observations of its J = 1 - 0 (102.6 GHz), J = 2 - 1 (205.2 GHz), and J = 3 - 2 (307.7 GHz) pure rotational emissions toward the Orion Bar. Our search for CF+, carried out using the IRAM 30m and APEX 12m telescopes, was motivated by recent theoretical...
Article
Extensions in frequency coverage coupled with sensitive spectroscopic techniques have enabled high resolution measurements of pure rotational spectra of deuteromethane and its 13-C substituted counterpart up to J' = 7. The current work reveals a small inconsistency in previously reported frequency measurements of (CH3D)-C-12 at J' = 5. (c) 2009 Els...

## Citations

... The hydrolysis of glycinamide forms glycine on the grain surface, which was presented in reactions 4 (Alonso et al., 2018). Recently, Kisiel et al. (2022) searched for the emission lines of glycinamide from Sgr B2(N) but they cannot find any evidence of glycinamide within the limit of the Local Thermodynamic Equi-librium (LTE) model. They estimated the upper limit column density of glycinamide towards Sgr B2(N) was ⩽1.5×10 16 cm −2 . ...
... Besides HOCN, already reported by Brünken et al. (2010) and Zeng et al. (2018), we have provided the tentative detections towards this source of HCOCN and HOCH 2 CN (third detection in the ISM), and the detection of the three unsaturated C 4 H 3 N isomers (being the second source after TMC-1 in which all three isomers are identified). These detections confirm the rich reservoir of nitriles in space, and complete the list of prebiotic molecular precursors detected previously, including species directly involved in the synthesis of ribonucleotides such as glycolaldehyde (HCOCH 2 OH; Hollis et al., 2004;Requena-Torres et al., 2006;Beltrán et al., 2009;Jørgensen et al., 2012), urea (Belloche et al., 2019;Jiménez-Serra et al., 2020), hydroxylamine NH 2 OH , and 1,2ethenediol (Rivilla et al. 2022a); of amino acids, such as amino acetonitrile (NH 2 CH 2 CN; Belloche et al., 2008;Melosso et al., 2020); and of lipids, such as ethanolamine (NH 2 CH 2 CH 2 OH; Rivilla et al., 2021a), and propanol (CH 3 CH 2 CH 2 OH; Jimenez-Serra et al. 2022;Belloche et al. 2022). ...
... A total of 54 molecular species (not counting isotopologues) have been identified in the parts of the spectrum surveyed to date: a 20 GHz-wide band at 7-mm wavelength with the ATCA interferometer and the Yebes 40-m telescope, a 8 GHz-wide band at 3-mm with NOEMA, and a 38 GHz-wide band between 3-mm and 0.6-mm with ALMA (Muller et al. 2011(Muller et al. , 2014(Muller et al. , 2016(Muller et al. , 2017 and references therein, Tercero et al. 2020). ...
... (HSPM) early results of the Protostellar Interferometric Line Survey (PILS): PILS is an unbiased molecular line survey around 345 GHz carried out with the Atacama Large Millimetre/submillimetre Array (ALMA) to study the physical conditions and the molecular complexity of the Class 0 solartype protostellar system and astrochemical template source IRAS 16293−2422 (Jørgensen et al. 2016). Through the high sensitivity of PILS and narrow lines towards one component of IRAS 16293-2422 (limiting line confusion) a number of species have been detected for the first time, including the organohalogen compound methyl chloride (CH 3 Cl) (Fayolle et al. 2017), nitrous acid (HONO) (Coutens et al. 2019) and, tentatively, 3-hydroxypropenal ). An important contribution of PILS has also been the numerous isotopologues of organic molecules, in particular deuterated variants, that were detcted for the first time in the interstellar medium (ISM). ...
... The deuterated species detected in the PILS data are the mono-deuterated isotopomers of the oxygen-bearing organics glycolaldehyde (Jørgensen et al. 2016), ethanol, ketene, formic acid and of mono-deuterated acetaldehyde species CH 3 CDO (Jørgensen et al. 2018) and CH 2 DCHO (Coudert et al. 2019;Manigand et al. 2020), of the nitrogenbearing organics isocyanic acid DNCO and the monodeuterated isotopomers of formamide (Coutens et al. 2016) and the cyanamide isotopologue HDNCN (Coutens et al. 2018) and sulfur-containing species such as the hydrogen sulfide isotopologue HD 34 S (Drozdovskaya et al. 2018). Also, the PILS data reveal the presence of doubly-deuterated organics including the methyl cyanide species CHD 2 CN (Calcutt et al. 2018), the methyl formate species CHD 2 OCHO (Manigand et al. 2019) and the dimethyl ether species CHD 2 OCH 3 (Richard et al. 2021) and enable new and more accurate constraints on the doubly-and triply-deuterated variants of methanol in the warm gas close to the protostars (Drozdovskaya et al. 2022;Ilyushin et al. 2022). ...
... To reproduce the spectrum of Orion KL observed by the TMRT and re-affirm the line identification, we fit it with a simple radiative transfer model. The emission of Orion KL (especially for strong lines) is complex, with contributions from several physical components including the foreground Hii region M42 (Wilson et al. 1997), the PDR between M42 and the molecular cloud (e.g., Natta et al. 1994), the externally heated "compact ridge" (e.g., Mangum & Wootten 1993;Wang et al. 2011;Tahani et al. 2016 (e.g., Mangum & Wootten 1993;Jacob et al. 2021), the extended ridge and plateau (e.g., Genzel & Stutzki 1989;Bernal et al. 2021) as well as some other millimeter continuum sources (e.g., Wu et al. 2014). Since only single-point data were available in our observations, it is difficult to assign the detected emission to specific physical structures within the beam, especially for molecular emission. ...
... Formamide (NH 2 CHO) is an interstellar complex organic molecule (iCOM, referring to C-bearing species with six atoms or more; Herbst & van Dishoeck 2009;Ceccarelli et al. 2017) and a key precursor of more complex organic molecules, that can lead to the origin of life, because of its potential to form peptide bonds (Saladino et al. 2012;Kahane et al. 2013;López-Sepulcre et al. 2019). It has been detected in the gas phase in hot corinos (Kahane et al. 2013;Coutens et al. 2016;Imai et al. 2016;López-Sepulcre et al. 2017;Bianchi et al. 2019;Hsu et al. 2022), which are the hot (100 K) and compact (100 au) regions immediately around low-mass (Sun-like) protostars (Ceccarelli et al. 2007). The formamide origin is still under debate. ...
... However, for p3, both −15 to 5 km s -1 and 5-20 km s −1 velocity components contribute significantly to the emission. Thus, we carried out the PDR analysis for p3 for three cases: first, where we used the integrated intensities of The FIR intensities were determined using the formalism described in Goicoechea et al. (2015), where the dust parameters (dust temperature and opacity) were calculated from 70 and 160 μm data from the Herschel Space Archive (HSA), obtained within the Hi-GAL Galactic plane survey (Molinari et al. 2010) observed with the Photodetector Array Camera and Spectrometer (PACS; Poglitsch et al. 2010). A detailed description of the method is given in Tiwari et al. (2021). ...
... We have explicitly taken into account the rate coefficients between 10 and 100 K kinetic temperatures for 55 transitions in case of ortho-and 180 transitions in case of para-H 3 O + . For both sets of calculations the rotational energies along with the radiative transition frequencies and Einstein -coefficients were used as it is proposed in JPL data base (Pickett et al. (2010), Species Tag: 19004, version 3, compiled by Yu & Drouin, Jan. 2010). In total 11 rotational states (up to the = 5 + 3 state) were included in the analysis of ortho-H 3 O + , while in case of para-H 3 O + we considered the 20 lowest states (including the = 5 − 4 state as the highest, see Table. 1 for more details). ...
... In principle, the γ-ray emission from the decay of 44 Ti nuclei can be used as a tool for the search of remnants of recent supernovae (less than approx 1,000 years old) [15]. However, an unambiguous assignment of the X-and γ−ray emission of 44 Ti to specific sources has been so far only possible in the case of the For the main isotopologue 48 TiO purely high-resolution rotational data of the ground state were investigated by Namiki et al. [31] and Kania et al. [32]. Recently, Lincowski et al. [23] presented rotational measurements of all stable titanium isotopologues. ...