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EPoLM-4 2019, CSIC, Madrid, March 4-6, 2019, In this work we present an experimental setup in which millimetric-wave astronomical receivers and spectrometers are coupled to a reaction chamber to study the spectroscopy and chemical evolution of carbon containing molecular species of astrophysical interest, via their rotational emission lines. In a first proof of concept, a small prototype reactor (50 cm length, 25 cm diameter) was placed in the beam path of the Aries 40 m radio telescope (Yebes Observatory, Guadalajara, Spain) facing the Q-band receiver operating in the 41-49 GHz frequency range, providing 2 GHz bandwidth and 38 kHz resolution. The radiation signal received by the antenna, or that emitted by a liquid N2 trap, were used as cold background. Experiments with samples exposed to cold plasma generated by an inductively coupled RF (13.56 MHz) glow discharge, or UV irradiation, were performed; and the feasibility of the experiment was demonstrated [1]. In a second phase, new receivers have been designed and built, and are now coupled to a new larger reaction chamber (1 m length, 50 cm diameter), which provides longer optical paths and allows to operate at lower plasma pressures (¿ 0.1 Pa), in a dedicated laboratory. The new receivers cover the Q (31.5-50GHz) and W (72-116GHz) bands with 38 kHz resolution. A cryogenic cold load operates as background reference at 17 K. Plasmas produced in gas mixtures containing light hydrocarbons or other carbon bearing species and other gases are mainly employed for the spectroscopic study of the precursors, which dissociate in the plasma by electron impact, and the products, generated in gas phase or by heterogeneous reactions with the reactor surfaces [2]. In most cases, deposits produced by these plasmas on different sample substrates have been characterized ex-situ by different methods. The mm-wave emission technique provides large sensitivity, instantaneous bandwidth and spectral purity, so that it is perfectly suited for high resolution spectroscopy of molecular species of astrophysical importance. High accuracy measurements of the frequencies and intensities can be determined. Acknowledgments: We acknowledge funding from the U. E. Sinergy Grant (ERC-2013-Syg 610256, NANOCOSMOS) and the Spanish Research Agency through projects FIS201677726-C3-1-P and MAT2017-85089-c2-1R. References [1] I. Tanarro et al., A&A, 2018, 609, A15 [2] J. Cernicharo et al., A&A, 2019 (submitted)

Presentación 39 diapositivas. --- 45th EPS Conference on Plasma Physics, Žofín Palace, Prague, Czech Republic, from 2nd to 6th July 2018. -- https://www.fzu.cz/en/45th-european-physical-society-conference-on-plasma-physics, The development of new powerful radiotelescopes is enhancing tremendously the detection of stable and transient species in the interstellar space at mm and sub-mm wave wavelengths, and is improving the understanding of the kinetic processes involved. Evaluation of these data can take great advantage of the information obtained in laboratory cold plasmas. In this work we describe the proof of concept of the joint use of standard radio astronomical receivers and low pressure cold plasmas for emission spectroscopic studies of different precursors and products. The goal is to obtain in the laboratory valuable information on rotational emissions of molecular species of astrophysical interest at high spectral resolution. An inductively coupled RF discharge has been used to generate the plasma. Gas pressures 10-30 Pa allow stable plasma operation and produce column densities similar to those of interstellar clouds. The experiment is performed in the 40 m radio-telescope of the Observatory of Yebes (Spain), using its 41-49 GHz band receiver. The beam of the antenna pointing towards the zenith is used as cold emission background. The RF discharge doesn’t induce any electromagnetic spurious signals in the receiver, and astronomical detection of a SiO maser in the AGB star TX Cam is unaffected by the presence of the plasma. OCS is selected for preliminary gas detection in this emission band. OCS and CS2 are chosen as plasma precursors of the CS radical, which emits also in this region. O2 discharges applied after sulphur deposition on the reactor walls by the previous OCS and CS2 plasmas lead to the detection of SO2 produced by surface reactions. In conclusion, these experiments confirm the viability of using standard radioastronomy receivers to detect molecular and short lived species in gas simulation chambers based on plasma reactors., Spanish grants CSD2009‐00038 “ASTROMOL”, FIS2016‐77726‐C3‐1‐P; EU grant ERC‐2013‐Syg 610256 “NANOCOSMOS”

ICPIG (2017) ; Estoril, Lisbon, 9 to 14 July 2017 ; Ihttp://icpig2017.tecnico.ulisboa.pt/, We present a proof of concept on the coupling of cold plasmas and radio astronomical receivers, and the performances of the resulting setup for spectroscopy and chemical simulations of interest in the study of interstellar molecular clouds, where stars and planets form. OCS, CS2 and O2 were used as plasma precursors. The experiments were performed in an inductively coupled RF plasma reactor placed in the beam path of the 40m Radio Telescope receivers of Yebes Observatory (Spain)[1]., The authors acknowledge financial support from the U.E through the grant ERC-2013- Syg 610256-NANOCOSMOS and from Spanish MINECO though the grants SD2009- 00038 (Consolider Astromol), FIS2013-48087-C2-1-P. and FIS2016-77726-C3-1-P.

© 2014 AIP Publishing LLC. The negatively charged nitrogen vacancy center (NV) in diamond has generated significant interest as a platform for quantum information processing and sensing in the solid state. For most applications, high quality optical cavities are required to enhance the NV zero-phonon line (ZPL) emission. An outstanding challenge in maximizing the degree of NV-cavity coupling is the deterministic placement of NVs within the cavity. Here, we report photonic crystal nanobeam cavities coupled to NVs incorporated by a delta-doping technique that allows nanometer-scale vertical positioning of the emitters. We demonstrate cavities with Q up to ∼24 000 and mode volume V ∼ 0.47(λ/n)3 as well as resonant enhancement of the ZPL of an NV ensemble with Purcell factor of ∼20. Our fabrication technique provides a first step towards deterministic NV-cavity coupling using spatial control of the emitters.

La conexión establecida a lo largo de la Historia entre las matemáticas y la astronomía, ha sido profunda y fructífera para ambas. Las dos ciencias se han beneficiado mutuamente de un intercambio constituido por la formulación de problemas interesantes que generaban novedosas técnicas de cálculo, las cuales al ser aplicadas propiciaban la aparición de nuevos retos impulsando la investigación en un incesante avance. En este trabajo se pasa revista someramente a los principales hitos de esta fértil relación, prestando especial atención a los desarrollos modernos.