Search

International audience; We present the discovery and analysis of J1316+2614 at z = 3.6130, a UV-bright star-forming galaxy (MUV ≃ -24.7) with large escape of Lyman continuum (LyC) radiation. J1316+2614 is a young (≃10 Myr) star-forming galaxy with SFR ≃ 500 M⊙ yr-1 and a starburst mass of log(M⋆/M⊙) ≃ 9.7. It shows a very steep UV continuum, βUV = -2.59 ± 0.05, consistent with residual dust obscuration, E(B - V) ≃ 0. LyC emission is detected with high significance (≃17σ) down to 830 Å, for which a very high relative (absolute) LyC escape fraction $f_{\rm esc} \rm (LyC) \simeq 0.92$ (≃0.87) is inferred. The contribution of a foreground or active galactic nucleus contamination to the LyC signal is discussed, but is unlikely. J1316+2614 is the most powerful ionizing source known among the star-forming galaxy population, both in terms of production (QH ≍ 1056 s-1) and escape of ionizing photons ($f_{\rm esc} \rm (LyC) \approx 0.9$). Nebular emission in Ly α, H β, and other rest-frame optical lines are detected, but these are weak ($EW_{0} \rm [H\beta ] \simeq 35$ Å), with their strengths reduced roughly by $\simeq 90{{\ \rm per\ cent}}$. J1316+2614 is the first case known where the effect of large escape of ionizing photons on the strength of nebular lines and continuum emission is clearly observed. Gas inflows are detected in J1316+2614 from the blue-dominated peak Ly α emission (with a blue-to-red peak line ratio Iblue/Ired ≃ 3.7) and redshifted interstellar medium absorption (≃100 km s-1). Our results suggest that J1316+2614 is undergoing a gas compaction event, possibly representing a short-lived phase in the evolution of massive and compact galaxies, where strong gas inflows have triggered an extreme star formation episode and nearly 100 per cent LyC photons are escaping.

Carbon is an essential element for life but how much can be delivered to young planets is still an open question. The chemical characterization of planet-forming disks is a crucial step in our understanding of the diversity and habitability of exoplanets. Very low-mass stars ($, version submitted to Nature Astronomy

We analyse the star formation (SF) relations in a sample of 16 nearby luminous infrared galaxies (LIRGs) with more than 2800 regions defined on scales of 90 to 500 pc. We used ALMA to map the distribution of the cold molecular gas traced by the J = 2–1 line of CO and archival Paα HST/NICMOS imaging to trace the recent SF. In four objects we find two different branches in the Kennicutt-Schmidt relation at 90 pc scales, suggesting the existence of a duality in this relation. The two branches correspond to two different dynamical environments within each galaxy. One branch, which corresponds to the central region of these galaxies (90% of the regions are located at radii < 0.85 kpc), shows higher gas and SF rate surface densities with higher velocity dispersion. The other branch, which shows lower molecular gas and SF rate surface densities, corresponds to the more external disk regions (r ∼ 1 kpc). Despite the scatter, the SF efficiency of the galaxies with dual behaviour increases with increasing boundedness as measured by the b parameter (b≡ ΣH2/σ2 ∝ αvir−1). At larger spatial scales (250 and 500 pc), the duality disappears. The rest of the sample does not show evidence of this dual behaviour at any scale. © ESO 2022., M.S.G. acknowledges support from the Spanish Ministerio de Economía y Competitividad through the grants BES-2016-078922, ESP2017-83197-P. L.C. and M.S.G. acknowledge support from the research project PID2019-106280GB-100. M.P.S. acknowledges support from the Comunidad de Madrid through the Atracción de Talento Investigador Grant 2018-T1/TIC-11035 and PID2019-105423GA-I00 (MCIU/AEI/FEDER,UE). A.A.-H. and S.G.-B. work was funded by grant PGC2018-094671-B-I00 funded by MCIN/AEI/ 10.13039/501100011033 and by ERDF A way of making Europe. S.G.B. acknowledges support from the research project PID2019-106027GA-C44 of the Spanish Ministerio de Ciencia e Innovación. J.P.L. acknowledges support from PID2019-105423GA-I00. E.B. acknowledges the support from Comunidad de Madrid through the Atracción de Talento grant 2017-T1/TIC-5213. S.C. acknowledges financial support from the State Agency for Research of the Spanish MCIU through the ‘Centre of Excellence Severo Ochoa’ award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709). A.L. acknowledges the support from Comunidad de Madrid through the Atracción de Talento Investigador Grant 2017-T1/TIC-5213, and PID2019-106280GB-I00 (MCIU/AEI/FEDER,UE) This paper makes use of the following ALMA data: ADS/JAO.ALMA#2017.1.00255.S, ADS/JAO.ALMA#2013.1.00271.S, ADS/JAO.ALMA#2013.1.00243.S, ADS/JAO.ALMA#2015.1.00714.S and ADS/JAO.ALMA#2017.1.00395.S. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada) and NSC and ASIAA (Taiwan) and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

We study molecular outflows in a sample of 25 nearby (z< 0.17, d 300 km/s) molecular gas disconnected from the galaxy rotation, which we attribute to outflows. In 77% of the 26 nuclei with $\log L_{IR}/L_{\odot}>11.8$, we identifid molecular outflows with an average $v_{out}= 490$ km/s, outflow masses $1-35 \times 10^7$ $M_{\odot}$, mass outflow rates $\dot{M}_{out}=6-300$ $M_{\odot}$ yr$^{-1}$, mass-loading factors $η= \dot{M}_{out}/SFR = 0.1-1$, and an average outflow mass escape fraction of 45%. The majority of these outflows (18/20) are spatially resolved with radii of 0.2-0.9 kpc and have short dynamical times ($t_{dyn}=R_{out}/v_{out}$) in the range 0.5-2.8 Myr. The outflow detection rate is higher in nuclei dominated by starbursts (SBs, 14/15=93%) than in active galactic nuclei (AGN, 6/11=55%). Outflows perpendicular to the kinematic major axis are mainly found in interacting SBs. We also find that our sample does not follow the $\dot{M}_{out}$ versus AGN luminosity relation reported in previous works. In our analysis, we include a sample of nearby main-sequence galaxies (SFR = 0.3-17 $M_{\odot}$ yr$^{-1}$) with detected molecular outflows from the PHANGS-ALMA survey to increase the $L_{IR}$ dynamic range. Using these two samples, we find a correlation between the outflow velocity and the SFR, as traced by $L_{IR}$ ($v_{out} \propto SFR^{0.25\pm0.01})$, which is consistent with what was found for the atomic ionised and neutral phases. Using this correlation, and the relation between $M_{out}/R_{out}$ and $v_{out}$, we conclude that these outflows are likely momentum-driven., 27 pages, 23 figures; Appendix: 49 pages, 41 figures. Accepted for publication in Astronomy & Astrophysics. Typo corrected in Table 1 for galaxy 19297-0406

We present JWST/MIRI MRS spectroscopy of NGC 7319, the largest galaxy in the Stephan’s Quintet, observed as part of the Early Release Observations (ERO). NGC 7319 hosts a type 2 active galactic nucleus (AGN) and a low-power radio jet (L1.4 GHz = 3.3 × 1022 W Hz−1) with two asymmetric radio hotspots at 430 pc (N2) and 1.5 kpc (S2) projected distances from the unresolved radio core. The MRS data suggest that the molecular material in the disk of the galaxy decelerates the jet and causes this length asymmetry. We find enhanced emission from warm and hot H2 (Tw = 330 ± 40 K, Th = 900 ± 60 K) and ionized gas at the intersection between the jet axis and dust lanes in the disk. This emission is coincident with the radio hotspot N2, the hotspot closer to the core, suggesting that the jet–interstellar medium (ISM) interaction decelerates the jet. Conversely, the mid-infrared emission at the more distant hotspot is fainter, more highly ionized, and with lower H2 excitation, suggesting a more diffuse atomic environment where the jet can progress to farther distances. At the N2 radio hotspot, the ionized gas mass (Mion = (2.4–12)×105 M⊙) is comparable to that of the warm H2, but the former is more turbulent (σion ∼ 300 vs. σH2 ∼ 150 km s−1), so the mechanical energy of the ionized gas is ∼1.3–10 times higher. From these estimates, we find that only < 1% of the jet energy remains as mechanical energy in these two ISM phases at N2. We also find extended (r > 0.3–1.5 kpc) high-ionization emission ([Mg V], [Ne VI], and [Ne V]) close to the radio hotspots. This initial analysis of NGC 7319 shows the potential of MIRI/MRS to investigate the AGN feedback mechanisms due to radio jets and their radiation field in the, often heavily dust-enshrouded, central regions of galaxies. Understanding these mechanisms is an essential ingredient in the development of cosmological simulations of galaxy evolution.

The design and characterization of a multi-dipolar microwave electron cyclotron resonance (ECR) hydrogen plasma reactor are presented. In this configuration, 16 ECR sources are disposed uniformly along the azimuthal direction at a constant distance from the center of a cylindrical reactor. Several plasma diagnostics have been used to determine key parameters such as neutral species temperature; electron density and temperature; and H+, H2+, and H3+ ion energy distributions. The experimental characterization is supported by electromagnetic and magnetostatic field simulations as well as Particle In-Cell Monte Carlo Collisions simulations to analyze the observed ion energy distribution functions. Especially, we show that both electron density and temperature are spatially uniform, i.e., 1011 cm−3 and 3 eV, respectively. This plasma enables generating ion flux and energy in the ranges 1019–1022 ions m−2 s−1 and few keVs, respectively. The H2+ ion distribution function shows two populations which were attributed to surface effects. These features make this reactor particularly suitable for studying hydrogen plasma surface interaction under controlled conditions.

In mitochondrial oxidative phosphorylation, electron transfer from NADH or succinate to oxygen by a series of large protein complexes in the inner mitochondrial membrane (complexes I–IV) is coupled to the generation of an electrochemical proton gradient, the energy of which is utilized by complex V to generate ATP. In Euglena gracilis, a non-parasitic secondary green alga related to trypanosomes, these respiratory complexes totalize more than 40 Euglenozoa-specific subunits along with about 50 classical subunits described in other eukaryotes. In the present study the Euglena proton-pumping complexes I, III, and IV were purified from isolated mitochondria by a two-steps liquid chromatography approach. Their atypical subunit composition was further resolved and confirmed using a three-steps PAGE analysis coupled to mass spectrometry identification of peptides. The purified complexes were also observed by electron microscopy followed by single-particle analysis. Even if the overall structures of the three oxidases are similar to the structure of canonical enzymes (e.g. from mammals), additional atypical domains were observed in complexes I and IV: an extra domain located at the tip of the peripheral arm of complex I and a “helmet-like” domain on the top of the cytochrome c binding region in complex IV.

Blistering burst induced tungsten dust nanoparticles were observed for the first time when a tungsten sample is submitted to a hydrogen low-temperature discharge under low flux and low incident energy values (20, 120 and 220 eV) at a surface temperature of 500 K. Tungsten nanoparticles (∼50 nm) were organized in 2D domains with diameter that is well correlated to the blister volume losses by burst. These observations suggest that dust nanoparticles were generated from blistering burst.

The formation of carbon nanoparticles in low pressure magnetized H2/CH4and H2/C2H2plasmas is investigated using infrared quantum cascade laser absorption, mass spectrometry, and electrostatic probe measurements. Results showed that dust formation is correlated to the presence of a significant amount of large positively charged hydrocarbon ions. Large negative ions or neutral hydrocarbon were not observed. These results, along with a qualitative comparison of diffusion and reaction characteristic, suggest that a positive ion may contribute to the growth of nanoparticles in hydrocarbon magnetized plasmas.

We study the kinematic properties of the ionised gas outflows and ambient interstellar medium (ISM) in a large and representative sample of local luminous and ultra-luminous infrared galaxies (U/LIRGs) (58 systems, 75 galaxies) at galactic and sub-galactic (i.e., star-forming clumps) scales, thanks to integral field spectroscopy (IFS)-based high signal-to-noise integrated spectra. The velocity dispersion of the ionized ISM in U/LIRGs (〈σ〉 ~ 70 km s-1) is larger than in lower luminosity local star-forming galaxies (〈σ〉 ~ 25 km s-1). While for isolated disc LIRGs star formation appears to sustain turbulence, gravitational energy release associated with interactions and mergers plays an important role in driving σ in the U/LIRG range. We find that σ has a dependency on the star formation rate density (ΣSFR), which is weaker than expected if it were driven by the energy released by the starburst. The relatively small role of star formation (SF) driving the σ in U/LIRGs is reinforced by the lack of an increase in σ associated with high luminosity SF clumps. We also find that the impact of an active galactic nucleus (AGN) in ULIRGs is strong, increasing on average σ by a factor 1.5. Low-z U/LIRGs cover a range of velocity dispersion (σ ~ 30 to 100 km s-1) and star formation rate density (ΣSFR ~ 0.1 to 20 M⊙ yr-1 kpc-2) similar to those of high-z SFGs. Moreover, the observed weak dependency of σ on ΣSFR for local U/LIRGs (σ ∝ ΣSFR +0.06) is in very good agreement with that measured in some high-z samples. The presence of ionized gas outflows in U/LIRGs seems universal based on the detection of a broad, usually blueshifted, Hα line. The observed dependency of the maximum velocity of the outflow (Vmax) on the star formation rate (SFR) is of the type Vmax(non - AGN) ∝ SFR(LIR)+ 0.24. We find that AGNs in U/LIRGs are able to generate faster (~×2) and more massive (~× 1.4) ionized gas outflows than pure starbursts. The derived ionized mass loading factors (η) are in general below 1, with only a few AGNs above this limit. The escaping gas fraction is low with only less massive (log(M dyn/M⊙) < 10.4) U/LIRGs having outflowing terminal velocities higher than their escape velocities, and more massive galaxies retaining the gas, even if they host an AGN. The observed average outflow properties in U/LIRGs are similar to high-z galaxies of comparable SFR. However, while high-z galaxies seem to require ΣSFR > 1 M ⊙ yr-1 kpc-2 for launching strong outflows, this threshold is not observed in low-z U/LIRGs even after correcting for the differential fraction of the gas content. In the bright SF clumps found in LIRGs, ionized gas outflows appear to be very common (detection rate over 80%). Their observed properties are less extreme than those associated with the entire galaxy. The clumps in LIRGs follow the general size-L-σ scaling relations found for low- and high-z clumps, though they are in general smaller, less luminous, and are characterized by lower σ than at high-z. For a given observed (no internal extinction correction applied) star formation surface density, outflows in LIRG clumps would be about one to two orders of magnitude less energetic than the outflows launched by clumps in high-z SF galaxies., This work has been supported by the Spanish Ministry of Science and Innovation (MICINN) under grants ESP2007-65475-C02-01, AYA2010-21161-C02-01, AYA2012-32295, AYA2012-39408-C02-C01,and by the Marie Curie Initial Training Network ELIXIR of the European Commission under contract PITN-GA-2008-214227.

A modeling study of carbon clusters and dust particles formation through carbon graphite sputtering in argon DC discharges is presented. The model combines the description of plasma discharge kinetics, molecular growth and transport of carbon clusters and aerosol dynamics for dust particles. Results show that field reversal is a key effect that ensures trapping and growth of negatively charged molecular carbon clusters, which are the precursors for dust particles. The model enables prediction of the space–time distributions of carbon clusters density as well as dust particle density, average charge and average diameter. Results especially show that dust particles and carbon clusters exhibit a pronounced density maximum in the vicinity of the field reversal position. A parametric study is presented in order to analyze the model sensitivity to some key parameters used in the physical model.

We present the results of high resolution mapping of the CO(1-0) and CO(2-1) emission of the ultraluminous infrared galaxy (ULIRG) IRAS 10190+1322, with the IRAM interferometer, down to an angular resolution of ~0.3 arcsec. This object is composed of two interacting galaxies with a projected nuclear separation of 6 kpc, and was selected to analyze the physical and dynamical properties of the molecular gas in each galaxy in order to study the conditions that lead a galaxy pair to become ultraluminous in the infrared. With the exception of Arp 220, the closest ULIRG, this is the first time that the CO emission is morphologically and kinematically resolved in the two interacting galaxies of a ULIRG system. In one of the galaxies the molecular gas is highly concentrated, distributed in a circumnuclear disk of 1.7 kpc in size. The molecular gas in the presumably less infrared luminous galaxy is distributed in a more extended disk of 7.4 kpc. The molecular gas mass accounts for ~10% of the dynamical mass in each galaxy. Both objects are rich enough in molecular gas, Mgas ~ 4 10^9 Msun, as to experience an infrared ultraluminous phase., 4 pages, 3 figures. Accepted for publication in A&A Letters Special Issue for the new extended configuration of the Plateau de Bure Interferometer

We present preliminary results of our programme aimed at the study of asample of ULIRGs on the basis of two-dimensional (integral field)optical spectroscopy and multi-frequency high spatial resolution HSTimaging. In particular, we show here results on Mrk 273 and IRAS 12112+0305recently obtained with the INTEGRAL system at the 4.2 m WHT. Abrief comparison with the HST images is also made.

LINERs are found in ~30% of all bright galaxies, including luminous infrared galaxies. They form a heterogeneous class powered by a variety of ionizing mechanisms such as low-luminosity AGNs, starbursts, shocks, or any combination of these.In early-type spirals, LINERs are powered by a low-luminosity AGN, or by an AGN surrounded by circumnuclear star-forming regions. In luminous infrared galaxies, LINERs are powered by starbursts with associated wind-related extended shocks, and an AGN may play a minor role, if any. LINERs in some FR I radio galaxies show a strong evidence for the presence of a massive central black hole, and there are indications for the existence of shocks in the nuclear disks of these galaxies. Yet, the dominant ionizing mechanism for LINERs in radio-quiet ellipticals and FR I host galaxies is still unclear.Multifrequency high spatial resolution imaging and spectroscopy are essential to discriminate among the different ionizing mechanisms present in LINERs.

We developed a model for the nucleation, growth and transport of carbonaceous dust particles in a non‐reactive gas dc discharge where the carbon source is provided by cathode sputtering. In a first part, we considered only the initial phase of the discharge when the dust charge density remains small with respect to the electron density. We found that an electric field reversal at the entrance of the negative glow region promotes trapping of negatively charged clusters and dust particles, confining them for long times in the plasma and favoring molecular growth. An essential ingredient for this process is electron attachment, which negatively charges the initially neutral clusters. We also showed that the field reversal mechanism can operate to trap negative clusters and particles under both electropositive and strongly electronegative plasma.

Despite intense theoretical and observational effort during the past few years, two important questions in the field of active galaxies remain open and are the subject of vigorous debate.The first concerns the connection between the interaction/merger of galaxies and the generation of starburst and/or active nuclei. A large fraction of high luminosity radio galaxies (Baum et al. 1988), quasars (Hutchinga, 1987) and IRAS galaxies (Sanders et al. 1988), show the presence of a large companion or have a peculiar optical morphology which is offen interpreted as evidence of a recent merger or interaction. In Seyferts, there are also several examples of individual galaxies with clear evidence of interaction/merger (Colina et al. 1987; Fricke and Kollatschny, 1989; Macchetto et al. 1990). Also a significant fraction of low luminosity radio galaxies are associated with a system of two elliptical galaxies in interaction (Colina and Pérez-Fournon, 1990a,b).

We investigate the stellar populations in the star forming ring of the luminous infrared galaxy NGC 7469. We use Hubble Space Telescope multi-wavelength (UV through NIR) imaging complemented with new K-band ground-based long-slit spectroscopy, and mid-IR and radio maps. Spectral energy distributions (SEDs) and evolutionary synthesis models have been used to characterize the star formation at different scales from those of individual star clusters (tens of pc) to that of the entire star-forming ring (kpc scale). At the smallest scales two different populations of massive (1-10 x 10^6 Msun) clusters are identified. About 25% of the clusters are young (1-3 Myr) and extincted (A_V ~ 3 mag), whereas the vast majority are of intermediate age (~9 to 20 Myr) and less obscured (A_V ~ 1 mag). At larger (hundreds of pc) scale, an analysis of the integrated SED and spectroscopic data of the ring indicates the presence of two stellar populations. The young (5-6 Myr) and obscured stellar population accounts for the Br_gamma emission and most of the IR luminosity, and about one-third of the stellar mass of the ring. The much less obscured intermediate-age population has properties similar to those of the majority of the (older) 1.1um-selected star clusters. These two populations are spatially anti-correlated. The UV-optical-NIR continuum (including the majority of the clusters) of the ring traces mostly the mildly obscured intermediate-age population, while the MIR and radio peaks mark the location of the youngest and obscured star-forming regions. This study emphasizes the need for multi-wavelength, high-angular resolution observations to characterize the star formation in the dust-obscured regions commonly present in LIRGs., Comment: 17 pages, 10 figures. Accepted for publication in ApJ. Paper with high resolution images can be found at http://damir.iem.csic.es/extragalactic/publications/publications.html

We present diffraction-limited (FWHM ~ 0.3arcsec) Gemini/T-ReCS mid-infrared (MIR: N-band or narrow-band at 8.7micron) imaging of four Luminous Infrared Galaxies (LIRGs) drawn from a representative local sample. The MIR emission in the central few kpc is strikingly similar to that traced by Pa-alpha, and generally consists of bright nuclear emission and several compact circumnuclear and/or extranuclear HII regions. The central MIR emission is dominated by these powerful HII regions, consistent with the majority of AGN in this local sample of LIRGs contributing a minor part of the MIR emission. The luminous circumnuclear HII regions detected in LIRGs follow the extrapolation of the 8micron vs. Pa-alpha relation found for M51 HII knots. The integrated central 3-7kpc of galaxies, however, present elevated 8micron/Pa-alpha ratios with respect to individual HII regions, similar to the integrated values for star-forming galaxies. Our results show that the diffuse 8micron emission, not directly related to the ionizing stellar population, can be as luminous as that from the resolved HII regions. Therefore, calibrations of the star formation rate for distant galaxies should be based on the integrated 8micron emission of nearby galaxies, not that of the HII regions alone., Comment: Accepted for publication in Astrophysical Journal Letters. Paper with high resolution Fig.1 can be found at http://damir.iem.csic.es/extragalactic/publications/publications.html

22 pages, 4 figures.-- ArXiv pre-print available at: http://arxiv.org/abs/astro-ph/0606186, We use Hubble Space Telescope (HST) NICMOS continuum and Paα observations to study the near-infrared and star formation properties of a representative sample of 30 local (d ~ 35-75 Mpc) luminous infrared galaxies (LIRGs, infrared [8-1000 μm] luminosities of log LIR = 11-11.9 Lsun). The data provide spatial resolutions of 25-50 pc and cover the central ~3.3-7.1 kpc regions of these galaxies. About half of the LIRGs show compact (~1-2 kpc) Paα emission with a high surface brightness in the form of nuclear emission, rings, and minispirals. The rest of the sample show Paα emission along the disk and the spiral arms extending over scales of 3-7 kpc and larger. About half of the sample contains H II regions with Hα luminosities significantly higher than those observed in normal galaxies. There is a linear empirical relationship between the mid-IR 24 μm and hydrogen recombination (extinction-corrected Paα) luminosity for these LIRGs, and the H II regions in the central part of M51. This relation holds over more than four decades in luminosity, suggesting that the mid-IR emission is a good tracer of the star formation rate (SFR). Analogous to the widely used relation between the SFR and total IR luminosity of R. Kennicutt, we derive an empirical calibration of the SFR in terms of the monochromatic 24 μm luminosity that can be used for luminous, dusty galaxies., AAH and LC acknowledge support from the Spanish Programa Nacional de Astronomía y Astrofísica under grant AYA2002-01055 and Plan Nacional del Espacio ESP2005-01480, and PGPG from the Spanish Programa Nacional de Astronomía y Astrofísica under grant AYA 2004-01676. This work has been funded by NASA grant HST-GO-10169 and by NASA through contract 1255094 issued by JPL/Caltech.

Based on observations carried out with ALMA in Cycle 0.-- et al., [Aims]: We investigate the fueling and the feedback of star formation and nuclear activity in NGC 1068, a nearby (D = 14 Mpc) Seyfert 2 barred galaxy, by analyzing the distribution and kinematics of the molecular gas in the disk. We aim to understand if and how gas accretion can self-regulate. [Methods]: We have used the Atacama Large Millimeter Array (ALMA) to map the emission of a set of dense molecular gas (n(H2) ' 1056 cm3) tracers (CO(3-2), CO(6-5), HCN(4-3), HCO+(4-3), and CS(7-6)) and their underlying continuum emission in the central r ∼ 2 kpc of NGC 1068 with spatial resolutions ∼0:3000:500 (∼20-35 pc for the assumed distance of D = 14 Mpc). [Results]: The sensitivity and spatial resolution of ALMA give an unprecedented detailed view of the distribution and kinematics of the dense molecular gas (n(H2) ≈ 1056cm3) in NGC 1068. Molecular line and dust continuum emissions are detected from a r ∼ 200 pc off-centered circumnuclear disk (CND), from the 2.6 kpc-diameter bar region, and from the r ∼ 1:3 kpc starburst (SB) ring. Most of the emission in HCO+, HCN, and CS stems from the CND. Molecular line ratios show dramatic order-of-magnitude changes inside the CND that are correlated with the UV/X-ray illumination by the active galactic nucleus (AGN), betraying ongoing feedback. We used the dust continuum fluxes measured by ALMA together with NIR/MIR data to constrain the properties of the putative torus using CLUMPY models and found a torus radius of 20+6 10 pc. The Fourier decomposition of the gas velocity field indicates that rotation is perturbed by an inward radial flow in the SB ring and the bar region. However, the gas kinematics from r ∼ 50 pc out to r ∼ 400 pc reveal a massive (Mmol ∼ 2:7+0:9 1:2 × 107 M) outflow in all molecular tracers. The tight correlation between the ionized gas outflow, the radio jet, and the occurrence of outward motions in the disk suggests that the outflow is AGN driven. [Conclusions]: The molecular outflow is likely launched when the ionization cone of the narrow line region sweeps the nuclear disk. The outflow rate estimated in the CND, dM=dt ∼ 63+21 37 M yr1, is an order of magnitude higher than the star formation rate at these radii, confirming that the outflow is AGN driven. The power of the AGN is able to account for the estimated momentum and kinetic luminosity of the outflow. The CND mass load rate of the CND outflow implies a very short gas depletion timescale of ≤1 Myr. The CND gas reservoir is likely replenished on longer timescales by efficient gas inflow from the outer disk. © ESO 2014., S.G.B. and I.M. acknowledge support from Spanish grants AYA2010-15169 and from the Junta de Andalucia through TIC-114 and the Excellence Project P08-TIC-03531. S.G.B., A.L., and A.F. acknowledge support from MICIN within program CONSOLIDER INGENIO 2010, under grant “Molecular Astrophysics: The Herschel and ALMA Era–ASTROMOL” (ref CSD2009-00038). S.G.B., A.U., L.C., and P.P. acknowledge support from Spanish grant AYA2012-32295. FC acknowledges the European Research Council for the Advanced Grant Program Num. 267399-Momentum. A.A.H. acknowledges support from the Universidad de Cantabria through the Augusto G. Linares programme and from the Spanish Plan Nacional grants AYA2009-05705-E and AYA2012-31447. C.R.A. is supported by a Marie Curie Intra European Fellowship within the 7th European Community Framework Programme (PIEF-GA-2012-327934). C.R.A. also ackowledges financial support from the Spanish Ministry of Science and Innovation (MICINN) through project PN AYA2010-21887-C04.04 (Estallidos).

COSMOS is mapping 1 sq. degree of the sky at optical and NIR wavelengths, in four fields. Key scientific goals include the characterization of samples of galaxies with high rate of star formation at redshifts from 0 to 3, for future observations with GTC. The NIR data (155 arcmin2) was obtained with the newly commissioned INGRID on the WHT. Accurate sky subtraction was allowed by the use DIMSUM (IRAF). The Survey reaches K s = 21.5 mag/arcsec2 with S/N= 3 (Fig. 1). Seeing is 0.65″ in the combined images. Existing deep HST, CHANDRA and other data in these fields make COSMOS a unique tool for the study of distant galaxian populations.

This study reports the successful introduction into tumor cells of a ribozyme directed against an oncogene using a retroviral gene delivery system. A hammerhead ribozyme that selectively targets and cleaves the activated Ha-ras (V12Ras) oncogene was delivered using a retroviral vector and expressed under the control of a transfer RNA promoter in V12Ras-transformed 3T3 murine fibroblast and rat colon epithelial cells. The expression of V12Ras messenger RNA and V12Ras P21 protein was reduced by up to 100% and 75%, respectively, in cells transduced with functional ribozyme. Reductions in V12Ras expression correlated with the stable expression of the functional ribozyme in vivo and decreased tumorigenicity in nude mice. Ribozyme constructs containing identical antisense flanking regions, but a mutant catalytic center, did not attenuate V12Ras expression or decrease the tumorigenicity of transduced tumor cells. These data support the potential therapeutic role of antioncogene ribozymes.

The presence of nanostructured dust particles has been reported in thermonuclear fusion reactors with carbon plasma-facing components. These particles contribute to tritium retention and pollution of the edge plasma. Understanding the way these particles can grow in the plasma phase is necessary for designing engineering solutions that avoid or at least limit their formation. As a first step towards this goal, this paper presents a numerical study of the formation of dust in a simple model laboratory electrical discharge: a dc discharge generated in argon with a graphite electrode. The aim here is to investigate whether carbon sputtering through ion and fast neutral bombardment of the cathode and subsequent molecular growth of carbon clusters and particle nucleation and development can explain dust formation in this model discharge. Results show that field reversal effects and negative cluster formation and trapping can fully explain dust formation in such a dc discharge.

We have started an observational program to cover a representative sample of radio galaxies containing radio jets in order to study the optical properties of the parent galaxy, their relationship to the radio properties as well as to detect optical emission associated with the radio structures.

Sensitive high spatial resolution optical and infrared imaging and optical spectroscopy are presented for the active galaxy IC 5063. Physical and kinematic conditions are derived for the emission regions, and deep images of the dust and optical line emission are presented. These support the proposition that the gas and dust arise from a recent merger event. Strong evidence is found for the presence of a hidden, luminous ionization source in the nucleus of IC 5063. This comprises the detection of a broad faint H-alpha emission line with FWZI roughly 6000 km/s, the detection of high-excitation forbidden Fe VII emission lines and the presence of an extended emission-line region with a well-defined region of high excitation. One of the best examples of a highly anisotropic ionizing radiation field is found, with the high-excitation line emission displaying a distinctive X or conical morphology. This cone has a 50 deg opening angle in projection, extends over 22 kpc and has a large-scale X-type morphology, very probably due to dust obscuration of the ionization beam. This is in turn consistent with consideration of the energetic balance between the ionized gas and infrared emission. 69 refs.

This paper presents new VLA radio maps, at 6 cm and 20 cm, of the QSO MR 2251-178, together with deep high-spatial-resolution images in the O II forbidden 3727-A line in the O III forbidden 5007-A line, and H-alpha emission lines, showing the presence of extended emission-line filaments surrounding the MR 2251-178. The morphology of the circumnuclear emission-line regions and an extended system of filaments in different ionization states are shown. The physical characteristics, such as luminosities, densities, mass, and ionization parameters of different filaments are derived. 48 refs.

CCD imaging of 47 radio sources from the Bridle and Perley list of galaxies with radio jets is reported. All the observed galaxies are within the redshift range z = 0.01 - 0.15 and are constrained in position to delta - 15 deg or greater. The observations and the reduction procedure are described. Contour maps of all the sources are presented. Comments on individual galaxies as well as morphological features are given. 73 refs.

NGC 2992 is a nearby Seyfert galaxy (z=0.008, 1″=150 pc, for HO=75 km s−1 Mpc−1) seen almost edge-on (i=70°). A dust lane crossing the galaxy has been detected (Burbidge et al. 1972, see also Fig. 1) and the presence of two extended radio-emitting regions at position angles P.A. 130° and P.A. 160° has been reported (Ulvestad and Wilson, 1984).

CCD photometry of the jet in the Thuan-Gunn r and g filters obtained under good seeing conditions is presented. Elliptical models of the underlying stellar emission were subtracted from the reduced and calibrated images. The high signal to noise ratio and good spatial resolution make it possible to determine very accurately the morphological properties of the jet. These observations reveal a number of new features: the outermost knot (H) can be resolved into several components, and the spectral index of the knots between the r and g bands is in general steeper than in that in the radio and shows a trend to become steeper with distance from the nucleus. The implications of these results for current radiation jet models will be briefly discussed.

The variation of the CIV 1550A line strength in variable Seyfert I galaxies based on low resolution IUE data is discussed. The results suggest that the Baldwin-relation might not be a reliable distance indicator for QSO’s Seyfert I galaxies vary in a way indicating that the emission line gas is matter bounded when in a high state. For F-9 the transition from photon-bounded to matter bounded occurs at log{L(1350)} ≈ 29.7 erg/sec/Hz.

We present preliminary results of a CCD survey of nearby (z

In an earlier study on configurational factors in visual backward masking, varying amounts were deleted from the contour of a masking ring, and it was found that mask effectiveness was directly related to amount of contour present in the masking figure. In response to a question about whether the independent variable in that study was correctly identified as amount of contour in the masking figure rather than perhaps as the amount of its average contrast, we compared the masking effectiveness of both variables in the present experiment. The target was a black disk; its detectability was assessed by a two-alternative spatial forced-choice indicator response. The data clearly support the identification of the independent variable in the earlier study as amount of ring contour, although the two variables do have qualitatively similar effects on masking.

The behavior of the C IV 1550 A emission line strength in variable active galactic nuclei (AGNs) such as Seyfert 1 galaxies and one broad-line radio galaxy (BLRG) is discussed on the basis of low-resolution spectra from IUE. The results are compared with those obtained previously for QSO samples. The variation of individual AGNs indicate that they present matter-bounded conditions when the AGN is in a high-luminosity state. Such behavior is illustrated by the variations seen in the Seyfert 1 galaxy F9, where the transition from photon-bounded to matter-bounded occurs at a transition luminosity of ergs/sec per Hz. The results indicate the existence of a transition luminosity, which appears to be typical for an individual galaxy. An absolute luminosity limit also appears to be present both in the C IV line at 45.0 ergs/sec and for the continuum at 31.7 ergs/sec per Hz. 25 references.

CCD photometry of the M87 jet in the Thuan-Gunn r and g filters is presented. Accurate elliptical models of the underlying stellar emission were subtracted from the reduced and calibrated frames. The residual images show a number of morphological features not clearly seen before such as the faint extension at the end of the jet and faint red diffuse emission parallel to the jet on its northern side. The optical spectrum of the knots between the r and g bands is steeper than in the radio and, in general, becomes steeper with distance from the nucleus. The implications of this new result for particle acceleration mechanisms in jets are briefly discussed. The nondetection of a counterjet at an intensity level 300 times fainter than the jet places stronger constraints to relativistic beaming models of M87. 30 references.