Proyecto de Investigación: FORMACION ESTELAR EN MULTIPLES ESCALAS ESPACIALES EN LA EPOCA DE ALMA
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AYA2016-79006-P
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Seeds of Life in Space (SOLIS) VII. Discovery of a cold dense methanol blob toward the L1521F VeLLO system.
(EDP Sciences, 2020-04-02) Favre, C.; Vastel, C.; Jiménez Serra, I.; Quénard, D.; Caselli, P.; Ceccarelli, C.; Chacón Tanarro, A.; Fontani, F.; Holdship, J.; Oya, Y.; Punanova, A.; Saki, N.; Spezzano, S.; Yamamoto, S.; Neri, R.; López Sepulcre, A.; Alves, F.; Bachiller, R.; Balucani, N.; Bianchi, E.; Bizzocchi, L.; Codella, C.; Caux, E.; De Simone, M.; Enrique Romero, J.; Dulieu, F.; Feng, S.; Al Edhari, A. J.; Lefloch, B.; Ospina Zamudio, J.; Pineda, J.; Podio, L.; Rimola, A.; Segura Cox, D.; Sims, I. R.; Taquet, V.; Testi, L.; Theulé, P.; Ugliengo, P.; Vasyunin, A. I.; Vazart, F.; Viti, S.; Witzel, A.; Agence Nationale de la Recherche (ANR); Spanish FEDER; Russian Science Foundation (RSF); European Research Council (ERC); Agencia Estatal de Investigación (AEI); Al Edhari, A. J. [0000-0003-4089-841X]; Rimola, A. [0000-0002-9637-4554]; Balucani, N. [0000-0001-5121-5683]; Ceccarelli, C. [0000-0001-9664-6292]; De Oliveira Alves, F. [0000-0002-7945-064X]; Pineda, J. E. [0000-0002-3972-1978]; Segura Cox, D. [0000-0003-3172-6763]; Bachiller, R. [0000-0002-5331-5386]; Fontani, F. [0000-0003-0348-3418]; Sakai, N. [0000-0002-3297-4497]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Aims. The Seeds Of Life In Space IRAM/NOEMA large program aims at studying a set of crucial complex organic molecules in a sample of sources with a well-known physical structure that covers the various phases of solar-type star formation. One representative object of the transition from the prestellar core to the protostar phases has been observed toward the very low luminosity object (VeLLO) L1521F. This type of source is important to study to link prestellar cores and Class 0 sources and also to constrain the chemical evolution during the process of star formation.
Methods. Two frequency windows (81.6–82.6 GHz and 96.65–97.65 GHz) were used to observe the emission from several complex organics toward the L1521F VeLLO. These setups cover transitions of ketene (H2CCO), propyne (CH3CCH), formamide (NH2CHO), methoxy (CH3O), methanol (CH3OH), dimethyl ether (CH3OCH3), and methyl formate (HCOOCH3).
Results. Only two transitions of methanol (A+, E2) have been detected in the narrow window centered at 96.7 GHz (with an upper limit on E1) in a very compact emission blob (~7′′ corresponding to ~1000 au) toward the northeast of the L1521F protostar. The CS 2–1 transition is also detected within the WideX bandwidth. Consistently with what has been found in prestellar cores, the methanol emission appears ~1000 au away from the dust peak. The location of the methanol blob coincides with one of the filaments that have previously been reported in the literature. The excitation temperature of the gas inferred from methanol is (10 ± 2) K, while the H2 gas density (estimated from the detected CS 2–1 emission and previous CS 5–4 ALMA observations) is a factor >25 higher than the density in the surrounding environment (n(H2) ≥ 107 cm−3).
Conclusions. Based on its compactness, low excitation temperature, and high gas density, we suggest that the methanol emission detected with NOEMA is (i) either a cold and dense shock-induced blob that formed recently (≤ a few hundred years) by infalling gas or (ii) a cold and dense fragment that may just have been formed as a result of the intense gas dynamics within the L1521F VeLLO system.
Searching for molecular gas inflows and outflows in the nuclear regions of five Seyfert galaxies.
(EDP Sciences, 2020-11-13) Domínguez Fernández, A. J.; Alonso Herrero, A.; García Burillo, S.; Davies, R. I.; Usero, A.; Labiano, Á.; Levenson, N. A.; Pereira Santaella, M.; Imanishi, M.; Ramos Almeida, C.; Rigopoulou, D.; Agencia Estatal de Investigación (AEI); Ministerio de Economía y Competitividad (MINECO); Comunidad de Madrid; Science and Technology Facilities Council (STFC); Ramos Almeida, C. [https://orcid.org/0000-0001-8353-649X]; Davies, R. [https://orcid.org/0000-0003-4949-7217]; Alonso Herrero, A. [https://orcid.org/0000-0001-6794-2519]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Active galactic nucleus (AGN) driven outflows are believed to play an important role in regulating the growth of galaxies, mostly via negative feedback. However, their effects on their hosts are far from clear, especially for low- and moderate-luminosity Seyferts. To investigate this issue, we obtained cold molecular gas observations, traced by the CO(2-1) transition, using the NOEMA interferometer of five nearby (distances between 19 and 58 Mpc) Seyfert galaxies. The resolution of ∼0.3–0.8 (∼30–100 pc) and field of view of NOEMA allowed us to study the CO(2-1) morphology and kinematics in the nuclear regions (∼100 pc) and up to radial distances of ∼900 pc. We detected CO(2-1) emission in all five galaxies with disky or circumnuclear ring-like morphologies. We derived cold molecular gas masses on nuclear (∼100 pc) and circumnuclear (∼650 pc) scales in the range from 106 to 107 M⊙ and from 107 to 108 M⊙, respectively. In all of our galaxies, the bulk of this gas is rotating in the plane of the galaxy. However, noncircular motions are also present. In NGC 4253, NGC 4388, and NGC 7465, we can ascribe the streaming motions to the presence of a large-scale bar. In Mrk 1066 and NGC 4388, the noncircular motions in the nuclear regions are explained as outflowing material due to the interaction of the AGN wind with molecular gas in the galaxy disk. We conclude that for an unambiguous and precise interpretation of the kinematics of the cold molecular gas, we need detailed knowledge of the host galaxy (i.e., presence of bars, interactions, etc.), and also of the ionized gas kinematics and ionization cone geometry.
