Molecular gas in AzTEC/C159: a star-forming disk galaxy 1.3 Gyr after the Big Bang

We studied the molecular gas properties of AzTEC/C159, a star-forming disk galaxy at z = 4.567, in order to better constrain the nature of the high-redshift end of the submillimeter-selected galaxy (SMG) population. We secured ^(12)CO molecular line detections for the J = 2 →1 and J = 5 →4 transitions using the Karl G. Jansky Very Large Array (VLA) and the NOrthern Extended Millimeter Array (NOEMA) interferometer. The broad (FWHM ~ 750 km s^(−1)) and tentative double-peaked profiles of the two ^(12)CO lines are consistent with an extended molecular gas reservoir, which is distributed in a rotating disk, as previously revealed from [CII] 158 μm line observations. Based on the 12CO(2 →1) emission line, we derived L′_(CO)=(3.4±0.6)×10^(10) K km s^(−1) pc^2, which yields a molecular gas mass of M_(H2)(α_(CO)/4.3)=(1.5±0.3)×10^(11) M⊙ and unveils a gas-rich system with μ_(gas)(α_(CO)/4.3)≡M_(H2)/M⋆=3.3±0.7. The extreme star formation efficiency of AzTEC/C159, parametrized by the ratio L_(IR)/L′_(CO)=(216±80) L⊙ (K km s^(−1) pc^2)^(−1), is comparable to merger-driven starbursts such as local ultra-luminous infrared galaxies and SMGs. Likewise, the ^(12)CO(5 →4)/CO(2 →1) line brightness temperature ratio of r_(52)= 0.55 ± 0.15 is consistent with high-excitation conditions as observed in SMGs. Based on mass budget considerations, we constrained the value for the L′_(CO) – H_2 mass conversion factor in AzTEC/C159, that is, α_(CO)=3.9_(−1.3)^(+2.7) M⊙ K^(−1) km^(−1) s pc^(−2), which is consistent with a self-gravitating molecular gas distribution as observed in local star-forming disk galaxies. Cold gas streams from cosmological filaments might be fueling a gravitationally unstable gas-rich disk in AzTEC/C159, which breaks into giant clumps and forms stars as efficiently as in merger-driven systems and generates high gas excitation. These results support the evolutionary connection between AzTEC/C159-like systems and massive quiescent disk galaxies at z ~ 2

The XMM spectral catalog of SDSS optically selected Seyfert 2 galaxies

We present an X-ray spectroscopic study of optically selected (SDSS) Seyfert 2 (Sy2) galaxies. The goal is to study the obscuration of Sy2 galaxies beyond the local universe, using good quality X-ray spectra in combination with high S/N optical spectra for their robust classification. We analyzed all available XMM-Newton archival observations of narrow emission line galaxies that meet the above criteria in the redshift range 0.05<z<0.35. We initially selected narrow line AGN using the SDSS optical spectra and the BPT classification diagram. We further modeled and removed the stellar continuum, and we analyzed the residual emission line spectrum to exclude any possible intermediate-type Seyferts. Our final catalog comprises 31 Sy2 galaxies with median redshift z~0.1. X-ray spectroscopy is performed using the available X-ray spectra from the 3XMM and the XMMFITCAT catalogs. Implementing various indicators of obscuration, we find seven (~23%) Compton-thick AGN. The X-ray spectroscopic Compton-thick classification agrees with other commonly used diagnostics, such as the X-ray to mid-IR luminosity ratio and the X-ray to [OIII] luminosity ratio. Most importantly, we find four (~13%) unobscured Sy2 galaxies, at odds with the simplest unification model. Their accretion rates are significantly lower than the rest of our Sy2 sample, in agreement with previous studies that predict the absence of the broad line region below a certain Eddington ratio threshold.Comment: 12 pages, 6 figures, accepted for publication in A&

Molecular gas in AzTEC/C159: a star-forming disk galaxy 1.3 Gyr after the Big Bang

We studied the molecular gas properties of AzTEC/C159, a star-forming disk galaxy at z = 4.567, in order to better constrain the nature of the high-redshift end of the submillimeter-selected galaxy (SMG) population. We secured ^(12)CO molecular line detections for the J = 2 →1 and J = 5 →4 transitions using the Karl G. Jansky Very Large Array (VLA) and the NOrthern Extended Millimeter Array (NOEMA) interferometer. The broad (FWHM ~ 750 km s^(−1)) and tentative double-peaked profiles of the two ^(12)CO lines are consistent with an extended molecular gas reservoir, which is distributed in a rotating disk, as previously revealed from [CII] 158 μm line observations. Based on the 12CO(2 →1) emission line, we derived L′_(CO)=(3.4±0.6)×10^(10) K km s^(−1) pc^2, which yields a molecular gas mass of M_(H2)(α_(CO)/4.3)=(1.5±0.3)×10^(11) M⊙ and unveils a gas-rich system with μ_(gas)(α_(CO)/4.3)≡M_(H2)/M⋆=3.3±0.7. The extreme star formation efficiency of AzTEC/C159, parametrized by the ratio L_(IR)/L′_(CO)=(216±80) L⊙ (K km s^(−1) pc^2)^(−1), is comparable to merger-driven starbursts such as local ultra-luminous infrared galaxies and SMGs. Likewise, the ^(12)CO(5 →4)/CO(2 →1) line brightness temperature ratio of r_(52)= 0.55 ± 0.15 is consistent with high-excitation conditions as observed in SMGs. Based on mass budget considerations, we constrained the value for the L′_(CO) – H_2 mass conversion factor in AzTEC/C159, that is, α_(CO)=3.9_(−1.3)^(+2.7) M⊙ K^(−1) km^(−1) s pc^(−2), which is consistent with a self-gravitating molecular gas distribution as observed in local star-forming disk galaxies. Cold gas streams from cosmological filaments might be fueling a gravitationally unstable gas-rich disk in AzTEC/C159, which breaks into giant clumps and forms stars as efficiently as in merger-driven systems and generates high gas excitation. These results support the evolutionary connection between AzTEC/C159-like systems and massive quiescent disk galaxies at z ~ 2

Total Molecular Gas Masses of Planck - Herschel Selected Strongly Lensed Hyper Luminous Infrared Galaxies

We report the detection of CO(1 - 0) line emission from seven Planck and Herschel selected hyper luminous (LIR(8-1000um) > 10^13Lsun) infrared galaxies with the Green Bank Telescope (GBT). CO(1 - 0) measurements are a vital tool to trace the bulk molecular gas mass across all redshifts. Our results place tight constraints on the total gas content of these most apparently luminous high-z star-forming galaxies (apparent IR luminosities of LIR > 10^(13-14) Lsun), while we confirm their predetermined redshifts measured using the Large Millimeter Telescope, LMT (zCO = 1.33 - 3.26). The CO(1 - 0) lines show similar profiles as compared to Jup = 2 -4 transitions previously observed with the LMT. We report enhanced infrared to CO line luminosity ratios of = 110 (pm 22) Lsun(K km s^-1 pc^-2)^-1 compared to normal star-forming galaxies, yet similar to those of well-studied IR-luminous galaxies at high-z. We find average brightness temperature ratios of = 0.93 (2 sources), = 0.34 (5 sources), and = 0.18 (1 source). The r31 and r41 values are roughly half the average values for SMGs. We estimate the total gas mass content as uMH2 = (0.9 - 27.2) x 10^11(alphaCO/0.8)Msun, where u is the magnification factor and alphaCO is the CO line luminosity to molecular hydrogen gas mass conversion factor. The rapid gas depletion times are, on average, tau = 80 Myr, which reveal vigorous starburst activity, and contrast the Gyr depletion timescales observed in local, normal star-forming galaxies.Comment: published in MNRAS, 9pages, 5fig

Automated mining of the ALMA archive in the COSMOS field (A3COSMOS): II. Cold molecular gas evolution out to Redshift 6

We present new measurements of the cosmic cold molecular gas evolution out to redshift 6 based on systematic mining of the ALMA public archive in the COSMOS deep field (A3COSMOS). Our A3COSMOS dataset contains ~700 galaxies (0.3 < z < 6) with high-confidence ALMA detections in the (sub-)millimeter continuum and multi-wavelength spectral energy distributions (SEDs). Multiple gas mass calibration methods are compared and biases in band conversions (from observed ALMA wavelength to rest-frame Rayleigh-Jeans(RJ)-tail continuum) have been tested. Combining our A3COSMOS sample with ~1,000 CO-observed galaxies at 0 < z < 4 (75% at z < 0.1), we parameterize galaxies' molecular gas depletion time and molecular gas to stellar mass ratio (gas fraction) each as a function of the stellar mass, offset from the star-forming main sequence (Delta MS) and cosmic age (or redshift). Our proposed functional form provides a statistically better fit to current data (than functional forms in the literature), and implies a "downsizing" effect (i.e., more-massive galaxies evolve earlier than less-massive ones) and "mass-quenching" (gas consumption slows down with cosmic time for massive galaxies but speeds up for low-mass ones). Adopting galaxy stellar mass functions and applying our function for gas mass calculation, we for the first time infer the cosmic cold molecular gas density evolution out to redshift 6 and find agreement with CO blind surveys as well as semi-analytic modeling. These together provide a coherent picture of cold molecular gas, SFR and stellar mass evolution in galaxies across cosmic time

Probing the Timescale of the 1.4 GHz Radio emissions as a Star formation tracer

Radio used as a star formation rate (SFR) tracer presents enormous advantages by being unaffected by dust and radio sources being pinpointed at the sub-arc-second level. The interpretation of the low frequency 1.4 GHz luminosity is hampered by the difficulty in modeling the cosmic ray paths in the interstellar medium, and their interactions with the magnetic field. In this work, we compare the SFR derived from radio observations, and the ones derived from spectral energy distribution (SED) modeling. We aim at better understand the behavior of the SFR radio tracer, with a specific emphasis on the link with star-formation histories. We used the SED modeling code Code Investigating GALaxy Emission, CIGALE, with a non-parametric star formation history model (SFH) and fit the data over the wavelength range from the ultraviolet (UV) up to the mid-infrared (mid-IR). We interpret the difference between radio and SED-based SFR tracers in the light of recent gradients in the derived SFH. To validate the robustness of the results, we checked for any remaining active galaxy nuclei (AGN) contribution and tested the impact of our SFH modeling approach. Approximately 27% our galaxies present a radio SFR (SFR$_{\rm radio}$) at least ten times larger than the instantaneous SFR from SED-fitting (SFR$_{\rm SED}$). This trend affects primarily the galaxies that show a declining SFH activity over the last 300 Myr. Both SFR indicators converge toward a consistent value, when the SFHs are averaged over a period larger than 150 Myr to derive SFR$_{\rm SED}$. Although the radio at low frequency 1.4 GHz is a good tracer of the star formation activity of galaxies with constant or increasing SFH, our results indicate that this is not the case for galaxies that are quenching. Our analysis suggests that the star formation time sensitivity of the radio low frequency could be longer than 150 Myr.Comment: 10 pages, 10 figure

Variable broad lines and outflow in the weak blazar PBC J2333.9-2343

Indexación: Scopus; Scielo.Funding text #1 1Instituto de Física y Astronomía, Facultad de Ciencias, Universidad de Valparaíso, Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile 2INAF – Istituto di Astrofisica e Planetologia Spaziali di Roma (IAPS-INAF), Via del Fosso del Cavaliere 100, I-00133 Roma, Italy 3INAF – Osservatorio Astronomico di Roma, via Frascati 33, I-00078 Monte Porzio Catone, Italy 4Excellence Cluster Universe, Technische Universität München, Boltzmannstr. 2, D-85748, Garching, Germany 5European Southern Observatory, Karl-Schwarzschild-Str 2, D-85748 Garching b. München, Germany 6Instituto Nacional de Astrofísica, Óptica y Electrónica, Apartado Postal 51-216, 72000 Puebla, México 7Argelander Institute for Astronomy, University of Bonn, Auf dem Hügel 71, D-53121 Bonn, Germany 8International Max Planck Research School of Astronomy and Astrophysics at the Universities of Bonn and Cologne, Auf dem Hügel 69, D-53121 Bonn, Germany 9INAF – Osservatorio di Astrofisica e Scienza dello Spazio, via Gobetti 93/3, I-40129 Bo...View all Funding text #2 We acknowledge the referee, M. Villar Martín, for her comments and suggestions that helped to improve the paper. This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester, the NASA/IPAC extragalactic database (NED), the STARLIGHT code, and the IRAF software. Based upon observations carried out at the Observatorio Astronómico Nacional on the Sierra San Pedro Mártir (OAN-SPM), Baja California, México. LHG and FP acknowledge the ASI/INAF agreement number 2013-023-R1, LHG partial support from FONDECYT through grant 3170527, MP from ESSTI under the MoST, and from MINECO through research projects AYA2013-42227-P and AYA2016-76682-C3-1-P (AEI/FEDER, UE), LHG and SC from the Spanish grant AYA2013-42227-P, VC by CONACyT research grant 280789, EFJA from the Collaborative Research Center 956, subproject A1, funded by DFG, and GV from the DFG Cluster of Excellence ‘Origin and Structure of the Universe’ (www.universe-cluster.de).PBC J2333.9-2343 is a peculiar active nucleus with two giant radio lobes and a weak blazarlike nucleus at their centre. In this work we show new optical, ultraviolet (UV), and X-ray data taken from the San Pedro Mártir telescope, the New Technology Telescope, NTT/EFOSC2, and the Swift/XRT satellite. The source is highly variable at all frequencies, in particular the strongest variations are found in the broad Hα component with a flux increase of 61±4 per cent between 2009 and 2016, following the X-ray flux increase of 62±6 per cent between 2010 and 2016. We also detected a broad Hβ component in 2016, making the optical classification change from type 1.9 to type 1.8 in 1 yr. We have also detected a broad component of the [OIII]λ5007 line, which is blue-shifted and of high velocity, suggesting an origin from a highly disturbed medium, possibly an outflow. The line flux variability and broad widths are indicative of a jet that is, at least in part, responsible for the ionization of the broad line region (BLR) and narrow line region (NLR). © 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society.https://academic.oup.com/mnras/article-abstract/478/4/4634/4999938?redirectedFrom=fulltex

GHEP-ISFG collaborative exercise on mixture profiles of autosomal STRs (GHEP-MIX01, GHEP-MIX02 and GHEP-MIX03): results and evaluation

One of the main objectives of the Spanish and Portuguese-Speaking Group of the International Society for Forensic Genetics (GHEP-ISFG) is to promote and contribute to the development and dissemination of scientific knowledge in the area of forensic genetics. Due to this fact, GHEP-ISFG holds different working commissions that are set up to develop activities in scientific aspects of general interest. One of them, the Mixture Commission of GHEP-ISFG, has organized annually, since 2009, a collaborative exercise on analysis and interpretation of autosomal short tandem repeat (STR) mixture profiles. Until now, three exercises have been organized (GHEP-MIX01, GHEP-MIX02 and GHEP-MIX03), with 32, 24 and 17 participant laboratories respectively. The exercise aims to give a general vision by addressing, through the proposal of mock cases, aspects related to the edition of mixture profiles and the statistical treatment. The main conclusions obtained from these exercises may be summarized as follows. Firstly, the data show an increased tendency of the laboratories toward validation of DNA mixture profiles analysis following international recommendations (ISO/IEC 17025:2005). Secondly, the majority of discrepancies are mainly encountered in stutters positions (53.4%, 96.0% and 74.9%, respectively for the three editions). On the other hand, the results submitted reveal the importance of performing duplicate analysis by using different kits in order to reduce errors as much as possible. Regarding the statistical aspect (GHEP-MIX02 and 03), all participants employed the likelihood ratio (LR) parameter to evaluate the statistical compatibility and the formulas employed were quite similar. When the hypotheses to evaluate the LR value were locked by the coordinators (GHEP-MIX02) the results revealed a minor number of discrepancies that were mainly due to clerical reasons. However, the GHEP-MIX03 exercise allowed the participants to freely come up with their own hypotheses to calculate the LR value. In this situation the laboratories reported several options to explain the mock cases proposed and therefore significant differences between the final LR values were obtained. Complete information concerning the background of the criminal case is a critical aspect in order to select the adequate hypotheses to calculate the LR value. Although this should be a task for the judicial court to decide, it is important for the expert to account for the different possibilities and scenarios, and also offer this expertise to the judge. In addition, continuing education in the analysis and interpretation of mixture DNA profiles may also be a priority for the vast majority of forensic laboratories.Fil: Sala, Adriana Andrea. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Servicio de Huellas Digitales Genéticas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Crespillo, M.. Instituto Nacional de Toxicología y Ciencias Forenses; EspañaFil: Barrio, P. A.. Instituto Nacional de Toxicología y Ciencias Forenses; EspañaFil: Luque, J. A.. Instituto Nacional de Toxicología y Ciencias Forenses; EspañaFil: Alves, Cíntia. Universidad de Porto; PortugalFil: Aler, M.. Servicio de Laboratorio. Sección de Genética Forense y Criminalística; EspañaFil: Alessandrini, F.. Università Politecnica delle Marche. Department of Biomedical Sciences and Public Health; ItaliaFil: Andrade, L.. Instituto Nacional de Medicina Legal e Ciências Forenses, Delegação do Centro. Serviço de Genética e Biologia Forenses; PortugalFil: Barretto, R. M.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Bofarull, A.. Instituto Nacional de Toxicología y Ciencias Forenses; EspañaFil: Costa, S.. Instituto Nacional de Medicina Legal y Ciencias Forenses; PortugalFil: García, M. A.. Servicio de Criminalística de la Guardia Civil. Laboratorio Central de Criminalística. Departamento de Biología; EspañaFil: García, O.. Basque Country Police. Forensic Genetics Section. Forensic Science Unit; EspañaFil: Gaviria, A.. Cruz Roja Ecuatoriana. Laboratorio de Genética Molecular; EcuadorFil: Gladys, A.. Corte Suprema de Justicia de la Nación; ArgentinaFil: Gorostiza, A.. Grupo Zeltia. Genomica S. A. U.. Laboratorio de Identificación Genética; EspañaFil: Hernández, A.. Instituto Nacional de Toxicología y Ciencias Forenses; EspañaFil: Herrera, M.. Laboratorio Genda S. A.; ArgentinaFil: Hombreiro, L.. Jefatura Superior de Policía de Galicia. Brigada de Policía Científica. Laboratorio Territorial de Biología – ADN; EspañaFil: Ibarra, A. A.. Universidad de Antioquia; ColombiaFil: Jiménez, M. J.. Policia de la Generalitat – Mossos d’Esquadra. Divisió de Policia Científica. Àrea Central de Criminalística. Unitat Central de Laboratori Biològic; EspañaFil: Luque, G. M.. Instituto Nacional de Toxicología y Ciencias Forenses; EspañaFil: Madero, P.. Centro de Análisis Genéticos; EspañaFil: Martínez Jarreta, B.. Universidad de Zaragoza; EspañaFil: Masciovecchio, M. Verónica. IACA Laboratorios; ArgentinaFil: Modesti, Nidia Maria. Provincia de Córdoba. Poder Judicial; ArgentinaFil: Moreno, F.. Servicio Médico Legal. Unidad de Genética Forense; ChileFil: Pagano, S.. Dirección Nacional de Policía Técnica. Laboratorio de Análisis de ADN para el CODIS; UruguayFil: Pedrosa, S.. Navarra de Servicios y Tecnologías S. A. U.; EspañaFil: Plaza, G.. Neodiagnostica S. L.; EspañaFil: Prat, E.. Comisaría General de Policía Científica. Laboratorio de ADN; EspañaFil: Puente, J.. Laboratorio de Genética Clínica S. L.; EspañaFil: Rendo, F.. Universidad del País Vasco; EspañaFil: Ribeiro, T.. Instituto Nacional de Medicina Legal e Ciências Forenses, Delegação Sul. Serviço de Genética e Biologia Forenses; PortugalFil: Santamaría, E.. Instituto Nacional de Toxicología y Ciencias Forenses; EspañaFil: Saragoni, V. G.. Servicio Médico Legal. Departamento de Laboratorios. Unidad de Genética Forense; ChileFil: Whittle, M. R.. Genomic Engenharia Molecular; Brasi