The Atacama Large Millimeter/Submillimeter Array (ALMA) is now entering its 6th cycle of scientific observations. Starting with Cycle 3, science observations were no longer considered Ëarly Science" or "best efforts". Cycle 5 is now the third cycle of ßteady state" observations and Cycle 7 is advertised to begin ALMA "full science" operations. ALMA Full Science Operations will include all the capabilities that were agreed upon by the international consortium after the ALMA re-baselining effort. In this talk, I will detail the upcoming ALMA Cycle 5 observing capabilities, describe the process of selecting new observing modes for upcoming cycles and provide an update on the status of the ALMA Full Science capabilities.

The search for complex organic molecules (COMs) in the interstellar medium (ISM) relies heavily on the progress made in the laboratory to record and characterize the rotational spectra of these molecules. Almost 200 different molecules have been identified in the ISM so far, in particular thanks to millimeter-wavelength observations of the star-forming molecular cloud core Sgr B2(N) in the Galactic Center region. The advent of the Atacama Large Millimeter/submillimeter Array (ALMA) has recently opened a new door to explore the molecular complexity of the ISM. Thanks to its high angular resolution, the spectral confusion of star-forming cores can be reduced, and its tremendous sensitivity allows astronomers to detect molecules of low abundance that could not be probed by previous generations of telescopes. I will present results of the EMoCA survey conducted toward Sgr B2(N) with ALMA. The main goal of this spectral line survey is to decipher the molecular content of Sgr B2(N) in order to test the predictions of astrochemical numerical simulations and gain insight into the chemical processes at work in the ISM. I will in particular report on the tentative detection of N-methylformamideA. Belloche, A. A. Meshcheryakov, R. T. Garrod et al. 2017, A&A, in press, DOI: 10.1051/0004-6361/201629724 on the deuterium fractionation of COMsA. Belloche, H. S. P. Müller, R. T. Garrod, and K. M. Menten 2016, A&A, 587, A91 and on the detection of a branched alkyl molecule in the ISMA. Belloche, R. T. Garrod, H. S. P. Müller, and K. M. Menten 2014, Science, 345, 1584R. T. Garrod, A. Belloche, H. S. P. Müller, and K. M. Menten 2017, A&A, in press, DOI: 10.1051/0004-6361/201630254. The latter detection has unveiled a new domain in the structures available to the chemistry of star-forming regions and established a further connection to the COMs found in meteorites.

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A. Belloche, A. A. Meshcheryakov, R. T. Garrod et al. 2017, A&A, in press, DOI: 10.1051/0004-6361/201629724, A. Belloche, H. S. P. Müller, R. T. Garrod, and K. M. Menten 2016, A&A, 587, A91, A. Belloche, R. T. Garrod, H. S. P. Müller, and K. M. Menten 2014, Science, 345, 1584

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Quite recently, some of us detected iso-propyl cyanide as the first branched alkyl molecule in space.A. Belloche, R. T. Garrod, H. S. P. Müller, and K. M. Menten, Science 345 1584.he identification was made in an ALMA Cycle 0 and 1 molecular line survey of Sagittarius B2(N) at 3 mm. The branched isomer was only slightly less abundant than its straight-chain isomer with a ratio of about 2 : 5. While initial chemical models favored the branched isomer somewhat, more recent modelsR. T. Garrod, A. Belloche, H. S. P. Müller, and K. M. Menten, Astron. Astrophys., in press; doi: 10.1051/0004-6361/201630254.re able to reproduce the observed ratio. Moreover, the models predicted that among the next longer butyl cyanides (BuCNs) 2-methylbutyronitrile (2-MBN) should be more abundant than both n-BuCN and 3-MBN by factors of around 2, with t-BuCN being almost negligible. With the rotational spectra of t- and n-BuCN studied,Z. Kisiel, Chem. Phys. Lett. 118 134; M. H. Ordu et al., Astron. Astrophys. 541 A121.e investigated those of 2-MBN and 3-MBN betwen  ∼ 40 and  ∼ 400 GHz by conventional absorption spectroscopy and by chirped-pulse and resonator Fourier transform microwave (FTMW) spectroscopy. The analyses were guided by quantum-chemical calculations. Here we report the analysis of the low-energy conformer of 2-MBN and a search for it in our current ALMA data. Two additional conformers are higher by  ∼ 250 and  ∼ 280 cm⁻¹. The low-energy conformer displays a very rich rotational spectrum because of its great asymmetry (κ ≈ 0.14) and large a- and b-dipole moment components. Accurate ¹⁴N quadrupole coupling parameters were obtained from the FTMW spectral recordings.

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A. Belloche, R. T. Garrod, H. S. P. Müller, and K. M. Menten, Science 345 1584.T R. T. Garrod, A. Belloche, H. S. P. Müller, and K. M. Menten, Astron. Astrophys., in press; doi: 10.1051/0004-6361/201630254.a Z. Kisiel, Chem. Phys. Lett. 118 134; M. H. Ordu et al., Astron. Astrophys. 541 A121.w

Sulfur chemistry in the interstellar medium is clearly misunderstood, the tenth most abundant element in the Galaxy, it is depleted in molecular clouds by a factor of 1000 A. Tieftrunk; et al., 1994, A&A 289, 579 This suggests that sulfur chemistry is important on icy grain mantles, and that sulfur-bearing molecules may be not detected yet due to the lack of laboratory data. The present study is about thioacetaldehyde (CH₃CHS), the analog of acetaldehyde. Previously, the rotational spectra were recorded up to 40 GHz H. Kroto; et al., 1974, Chem. Phys. Lett. 29, 265H. Kroto; et al., 1976, J. Mol. Spectrosc. 62, 346 New spectra were recorded from 150 to 660 GHz using the Lille solid-state based spectrometer. The new fast version of the spectrometer using DDS component is particulary suitable for reactive species like thioacetaldehyde. Thioacetaldehyde was produced in-situ by pyrolisis at 750^° C and introduced in a 1m long pyrex cell in a flow mode. Analysis of the spectra is not obvious, like in acetaldehyde, as this molecule exhibits internal rotation of the methyl group. The internal rotation barrier is higher in thioacetaldehyde, 542 cm-1, than in acetaldehyde, 408 cm-1. However, the coupling between the internal rotation and the overall rotation in thioacetaldehyde is strong, the coupling parameter ρ value is 0.261 just slightly smaller than the acetaldehyde value of 0.329. The spectroscopic results and its searches in SgrB2 will be presented.
This work was supported by the CNES and the Action sur Projets de l'INSU, PCMI. This work was also done under ANR-13-BS05-0008-02 IMOLABS

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A. Tieftrunk; et al., 1994, A&A 289, 579. H. Kroto; et al., 1974, Chem. Phys. Lett. 29, 265, H. Kroto; et al., 1976, J. Mol. Spectrosc. 62, 346.

Many diffuse and translucent clouds lie along the line of sight between Earth and the Galactic Center that can be probed through molecular absorption at characteristic velocities. We highlight results of a study of diffuse and translucent clouds along the line of sight to Sgr B2, including SOFIA observations of SH near 1.4 THz and GBT PRIMOS observations from 4 to 50 GHz. We find significant variation in the chemical conditions within these clouds, and the abundances do not appear to correlate with the total optical depth. Additionally, from the GBT observations, we report the first detections of multiple complex organic molecules (COMs) in diffuse and translucent clouds, including CH₃CN, HC₃N, CH₃CHO, and NH₂CHO. We compare the GBT results to complementary observations of SH, H₂S, and others at mm, sub-mm, and THz frequencies from the NRAO 12m, Herschel HIFI, and SOFIA facilities, and comment on the insights into interstellar sulfur chemistry which is currently not well constrained.

A critical question regarding star formation near supermassive black holes (SMBHs) is whether tidal shear completely suppresses star formation or whether it induces star formation. The circumnuclear molecular ring orbiting the 4 million solar mass black hole Sgr A* in the inner few parsecs of the Galactic center is an excellent testing ground to study star formation in extreme tidal environments. We have carried out ALMA observations of SiO (5-4) line emission to resolve protostellar outflow candidates in the molecular ring and its interior. We will describe preliminary results of these observations. In addition, we will present ALMA and VLA observations of continuum sources that show bow-shock structures. The characteristics of these mm sources suggest the presence of protoplanetary disks. These continuum measurements suggest on-going low-mass star formation with the implication that gas clouds can survive near the strong tidal and radiation fields of the Galactic center.

The interplay between laboratory spectroscopy and observational astronomy has allowed for the chemical complexity of the interstellar medium (ISM) to be explored. Our laboratory studies involve the measurement of the rotational spectra of commercially available samples in the region 75-110 GHz, thus covering a portion of Band 3 of the Atacama Large Millimeter/submillimeter Array (ALMA). Up until recently, we have concentrated on medium-sized (5 to 9 heavy atoms) nitrogen- and oxygen-containing molecules and their vibrationally excited states. Examples include amino alcohols, such as alaninol (2-amino-1-propanol), and cyanides. Further, we have extended the capabilities of our segmented chirped-pulse spectrometer [1] with electrical discharge apparatus. We present here the recent results from our set-up, including the typical rotational spectra of astrochemically relevant samples and the discharge-enabled rotational spectroscopy of mixtures of simple organic molecules. These experimental results have yielded transitions that will facilitate the detection of these molecules in the ISM with ALMA, and the discharge experiments should allow us to consider formation pathways of organic molecules from smaller building blocks.

[1] B.E. Arenas, S. Gruet, A.L. Steber, B.M. Giuliano, M. Schnell, Phys. Chem. Chem. Phys. 19 (2017) 1751-1756.

The C₂H₄O₂ triplet found in the interstellar medium (ISM) consists of glycolaldehyde (CH₂OHCHO), acetic acid (CH₃COOH) and methyl formate (HCOOCH₃). The forming mechanism of their HCO-bearing component involves both gas-phase and grain-surface processes whose relative roles plays into fundamental questions within the fields of astrochemistry and astrobiology. Glycolaldehyde is closely related to ribose and deoxyribose, the primary components of genetic materials. The first detection of Glycolaldehyde was toward Sgr B2 with using NRAO 12 m telescope in 2000 (J. M. Hollis et al). A new careful search for glycolaldehyde toward the hot dense core Sgr B2 (N) is needed. While methyl formate has a large number of detected transitions throughout the ISM, the detection of acetic acid, the least abundant of these isomers, is more tentative. Mehringer et al. (1997) reported only 4 lines of acetic acid toward Sgr B2 Large Molecule Heimat source. Here, we confirm these detections of each species toward Sgr B2 (N) with the more sensitive and larger bandwidth from ALMA Band 3 observations (A. Belloche, 2012), providing us more transitions and more accurate continuum subtraction. Based on these results, the abundances and spatial distributions of the C₂H₄O₂ triplet species would be obtained and compared.

We have studied dimethyl ether, one of the so-called ‘astronomical weeds’, in the 214.6–265.3 GHz band. We have experimentally gathered a set of intensity calibrated, complete, and temperature resolved spectra from across the temperature range of 238–391 K. Using our previously reported method of analysisJ. McMillan, S. Fortman, C. Neese, F. DeLucia, ApJ. 795, 56 (2014) the point by point method, we are capable of generating the complete spectrum at astronomically significant temperatures. Many lines, of nontrivial intensity, which were previously not included in the available astrophysical catalogs have been found. Lower state energies and line strengths have been found for a number of lines which are not currently present in the catalogs. The extent to which this may be useful in making assignments will be discussed.

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J. McMillan, S. Fortman, C. Neese, F. DeLucia, ApJ. 795, 56 (2014),

A comprehensive analysis of a broadband 1.2 THz wide spectral survey of the Orion Kleinmann-Low nebula (Orion KL) has shown that nitrogen bearing complex organics trace systematically hotter gas than O-bearing organics toward this source. The origin of this O/N dichotomy remains a mystery. If complex molecules originate from grain surfaces, N-bearing species may be more difficult to remove from grain surfaces than O-bearing organics. Theoretical studies, however, have shown that hot (T=300 K) gas phase chemistry can produce high abundances of N-bearing organics while suppressing the formation of O-bearing complex molecules. In order to distinguish these distinct formation pathways we have obtained extremely high angular resolution observations of methyl cyanide (CH₃CN) using the Atacama Large Millimeter/Submillimeter Array (ALMA) toward Orion KL. By simultaneously imaging ¹³CH₃CN and CH₂DCN we map the temperature structure and D/H ratio of CH₃CN. We will present updated results of these observations and discuss their implications for the formation of N-bearing organics in the interstellar medium.