The mass and environmental dependence on the secular processes of AGN in terms of morphology, colour, and specific star-formation rate

Galaxy mass and environment play a major role in the evolution of galaxies. In the transition from star-forming to quenched galaxies, Active galactic nuclei (AGN) have also a principal action. However, the connections between these three actors are still uncertain. In this work we investigate the effects of stellar mass and the large-scale environment (LSS), on the fraction of optical nuclear activity in a population of isolated galaxies, where AGN would not be triggered by recent galaxy interactions or mergers. As a continuation of a previous work, we focus on isolated galaxies to study the effect of stellar mass and the LSS in terms of morphology (early- and late-type), colour (red and blue), and specific star formation rate (quenched and star-forming). To explore where AGN activity is affected by the LSS we fix the stellar mass into low- and high-mass galaxies. We use the tidal strength parameter to quantify their effects. We found that AGN is strongly affected by stellar mass in 'active' galaxies (namely late-type, blue, and star-forming), however it has no influence for 'quiescent' galaxies (namely early-type, red, and quenched), at least for masses down to $\rm 10^{10}\,[M_\odot]$. In relation to the LSS, we found an increment on the fraction of SFN with denser LSS in low-mass star forming and red isolated galaxies. Regarding AGN, we find a clear increment of the fraction of AGN with denser environment in quenched and red isolated galaxies, independently of the stellar mass. AGN activity would be 'mass triggered' in 'active' isolated galaxies. This means that AGN is independent of the intrinsic property of the galaxies, but on its stellar mass. On the other hand, AGN would be 'environment triggered' in 'quiescent' isolated galaxies, where the fraction of AGN in terms of sSFR and colour increases from void regions to denser LSS, independently of its stellar mass.Comment: 14 pages, 9 figures (11 pages and 6 figures without appendix), accepted for publication in Astronomy & Astrophysic

Isolated elliptical galaxies in the local Universe

We have studied a sample of 89 very isolated, elliptical galaxies at z < 0.08 and compared their properties with elliptical galaxies located in a high-density environment such as the Coma supercluster. Our aim is to probe the role of environment on the morphological transformation and quenching of elliptical galaxies as a function of mass. In addition, we elucidate the nature of a particular set of blue and star-forming isolated ellipticals identified here. We study physical properties of ellipticals such as color, specific star formation rate, galaxy size, and stellar age, as a function of stellar mass and environment based on SDSS data. We analyze the blue star-forming isolated ellipticals in more detail, through photometric characterization using GALFIT, and infer their star formation history using STARLIGHT. Among the isolated ellipticals ~ 20% are blue, 8% are star forming, and ~ 10% are recently quenched, while among the Coma ellipticals ~ 8% are blue and just <= 1% are star forming or recently quenched. There are four isolated galaxies (~ 4.5%) that are blue and star forming at the same time. These galaxies, with masses between 7 x 10^9 and 2 x 10^10 h-2 M_sun, are also the youngest galaxies with light-weighted stellar ages <= 1 Gyr and exhibit bluer colors toward the galaxy center. Around 30-60% of their present-day luminosity, but only < 5% of their present-day mass, is due to star formation in the last 1 Gyr. The processes of morphological transformation and quenching seem to be in general independent of environment since most of elliptical galaxies are 'red and dead', although the transition to the red sequence should be faster for isolated ellipticals. In some cases, the isolated environment seems to propitiate the rejuvenation of ellipticals by recent (< 1 Gyr) cold gas accretion.Comment: 23 pages, 15 figures (16 pages and 9 figures without appendices). A&A, in pres

The less significant role of large-scale environment than optical AGN in nearby, isolated elliptical galaxies

The formation and evolution of elliptical galaxies in low-density environments are less understood than classical elliptical galaxies in high-density environments. Isolated galaxies are defined as galaxies without massive neighbors within scales of galaxy groups. The effect of the environment at several Mpc scales on their properties has been barely explored. Here we study the role of large-scale environment in some physical properties of 573 isolated elliptical galaxies out to z=0.08. We use three environmental estimators of the large-scale structure within a projected radius of 5 Mpc around isolated galaxies: the tidal strength parameter, the projected density eta_k, and the distance to the fifth nearest neighbor galaxy. We find 80% of galaxies at lower densities correspond to 'red and dead' elliptical galaxies. Blue and red galaxies do not tend to be located in different environments according to eta_k. Almost all the isolated ellipticals in the densest large-scale environments are red or quenched, where a third of them are low-mass galaxies. The percentage of isolated elliptical galaxies located in the AGN region of the BPT diagram is 64%. We have identified 33 blue, star-forming isolated ellipticals using both color and sSFR. Half of them are star-forming nuclei in the BPT diagram, which is 5% of the galaxies in this diagram. The large-scale environment is not playing the primary role to determine the color or sSFR of isolated elliptical galaxies. The large-scale environment seems to be negligible from a stellar mass scale around 10^10.6 Msun, probably because of the dominant presence of AGN at higher masses. For lower masses, the processes of cooling and infall of gas from large scales are very inefficient in ellipticals. AGN might also be an essential ingredient to keep most of the low-mass isolated elliptical galaxies quenched.Comment: 15 pages, 6 figures (10 pages and 4 figures without appendices). Accepted for publication in A&

Yellowing and Granulation of ‘Magallanes’ Pummelo (Citrus maxima [Burm. ex Rumph] Merr) Fruit as Influenced by 1-Methylcyclopropene

The yellowing, granulation, and other physico-chemical characteristics of ‘Magallanes’ pummelo [Citrus maxima (Burm. ex Rumph) Merr] fruit treated with 1-methylcyclopene (1-MCP) for 8 h at 0, 50, or 500 nL L-1) were evaluated. L*, a*, b*, chroma and hue values gradually increased during 12 weeks of storage at ambient conditions (26.4 °C, 83.3% RH). Rind color became more vivid and yellow. Decay, juice content, and electrolyte leakage were similar among treatments. However, weight loss, visual quality, shriveling, pH, total soluble solids (TSS), titratable acidity (TA), and TSS:TA were affected by 1-MCP. Weight loss was lowered by 50 nL L-1 at 6 weeks after treatment (WAT). Treated fruit had better visual quality than control fruit at 6 and 9 WAT because of lesser shriveling. At 12 WAT, fruit treated with 500 nL L-1 exhibited highest %TA and lowest TSS:TA ratio. Granulation or vesicle drying was most frequently observed initially in the middle and stylar ends of fruit segments. Granulated samples exhibited higher pH and lower TSS than the non-granulated segments. 1-MCP but not storage period showed similar yellowing and granulation of ‘Magallanes’ pummelo as the control lot. 1-MCP maintained a good fruit visual quality longer

Wildlife Trade in Southern Palawan, Philippines

Southern Palawan is one of the hottest hotspots for illegal trade of wildlife in the Philippines. Large numbers of wildlife are transported either by fishing vessels or private chartered planes from the south of Palawan to Zamboanga, Cebu, Manila, Batangas and even to Malaysia. Parrots and mynas are among the species of birds most traded due to their huge demand in the market. Other birds that are also under considerable pressure of poaching are Palawan hornbill and White-bellied sea eagle. Apart from birds, other Palawan wildlife included in the illegal shipments are Palawan pangolin, Balabac mouse deer, Palawan bearcat, Palawan bearded pig, Southern Palawan tree squirrel, freshwater turtles and beetles. The present study identified species of conservation priority involved in trade. The study also presents data on traded wildlife species in Palawan including their market value, modes of transport, operation of wildlife traders in Palawan and trade routes

SDSS IV MaNGA: Dependence of Global and Spatially Resolved SFR-M ∗ Relations on Galaxy Properties

Indexación: Scopus.The galaxy integrated Hα star formation rate-stellar mass relation, or SFR(global)-M ∗(global) relation, is crucial for understanding star formation history and evolution of galaxies. However, many studies have dealt with SFR using unresolved measurements, which makes it difficult to separate out the contamination from other ionizing sources, such as active galactic nuclei and evolved stars. Using the integral field spectroscopic observations from SDSS-IV MaNGA, we spatially disentangle the contribution from different Hα powering sources for ∼1000 galaxies. We find that, when including regions dominated by all ionizing sources in galaxies, the spatially resolved relation between Hα surface density (ΣHα(all)) and stellar mass surface density (Σ∗(all)) progressively turns over at the high Σ∗(all) end for increasing M ∗(global) and/or bulge dominance (bulge-to-total light ratio, B/T). This in turn leads to the flattening of the integrated Hα(global)-M ∗(global) relation in the literature. By contrast, there is no noticeable flattening in both integrated Hα(H ii)-M ∗(H ii) and spatially resolved ΣHα(H ii)-Σ∗(H ii) relations when only regions where star formation dominates the ionization are considered. In other words, the flattening can be attributed to the increasing regions powered by non-star-formation sources, which generally have lower ionizing ability than star formation. An analysis of the fractional contribution of non-star-formation sources to total Hα luminosity of a galaxy suggests a decreasing role of star formation as an ionizing source toward high-mass, high-B/T galaxies and bulge regions. This result indicates that the appearance of the galaxy integrated SFR-M ∗ relation critically depends on their global properties (M ∗(global) and B/T) and relative abundances of various ionizing sources within the galaxies.http://iopscience.iop.org/article/10.3847/1538-4357/aaa9bc/met

The evolution of Balmer jump selected galaxies in the ALHAMBRA survey

We present a new color-selection technique, based on the Bruzual & Charlot models convolved with the bands of the ALHAMBRA survey, and the redshifted position of the Balmer jump to select star-forming galaxies in the redshift range 0.5 < z < 1.5. These galaxies are dubbed Balmer jump Galaxies BJGs. We apply the iSEDfit Bayesian approach to fit each detailed SED and determine star-formation rate (SFR), stellar mass, age and absolute magnitudes. The mass of the haloes where these samples reside are found via a clustering analysis. Five volume-limited BJG sub-samples with different mean redshifts are found to reside in haloes of median masses $\sim 10^{12.5 \pm 0.2} M_\odot$ slightly increasing toward z=0.5. This increment is similar to numerical simulations results which suggests that we are tracing the evolution of an evolving population of haloes as they grow to reach a mass of $\sim 10^{12.7 \pm 0.1} M_\odot$ at z=0.5. The likely progenitors of our samples at z$\sim$3 are Lyman Break Galaxies, which at z$\sim$2 would evolve into star-forming BzK galaxies, and their descendants in the local Universe are elliptical galaxies.Hence, this allows us to follow the putative evolution of the SFR, stellar mass and age of these galaxies. From z$\sim$1.0 to z$\sim$0.5, the stellar mass of the volume limited BJG samples nearly does not change with redshift, suggesting that major mergers play a minor role on the evolution of these galaxies. The SFR evolution accounts for the small variations of stellar mass, suggesting that star formation and possible minor mergers are the main channels of mass assembly.Comment: 14 pages, 10 figures. Submitted to A&A. It includes first referee's comments. Abstract abridged due to arXiv requirement

DEVELOPMENT OF A CROSSFLOW FILTER TO REMOVE SOLIDS FROM RADIOACTIVE LIQUID WASTE: COMPARISON OF TEST DATA WITH OPERATING EXPERIENCE - 9119

In 2008, the Savannah River Site (SRS) began treatment of liquid radioactive waste from its Tank Farms. To treat waste streams containing {sup 137}Cs, {sup 90}Sr, and actinides, SRS developed the Actinide Removal Process (ARP) and the Modular Caustic Side Solvent Extraction Unit (MCU). The Actinide Removal Process contacts the waste with monosodium titanate (MST) to sorb strontium and select actinides. After MST contact, the process filters the resulting slurry to remove the MST (with sorbed strontium and actinides) and any entrained sludge. The filtrate is transported to the MCU to remove cesium. The solid particle removed by the filter are concentrated to {approx} 5 wt %, washed to reduce the concentration of dissolved sodium, and transported to the Defense Waste Processing Facility (DWPF) for vitrification. The authors conducted tests with 0.5 {micro} and 0.1 {micro} Mott sintered stainless steel crossflow filter at bench-scale (0.19 ft{sup 2} surface area) and pilot-scale (11.2 ft{sup 2}). The collected data supported design of the filter for the process and identified preferred operating conditions for the full-scale process (230 ft{sup 2}). The testing investigated the influence of operating parameters, such as filter pore size, axial velocity, transmembrane pressure, and solids loading, on filter flux, and validated the simulant used for pilot-scale testing. The conclusions from this work follow: (1) The 0.1 {micro} Mott sintered stainless steel filter produced higher flux than the 0.5 {micro} filter. (2) The filtrate samples collected showed no visible solids. (3) The filter flux with actual waste is comparable to the filter flux with simulated waste, with the simulated waste being conservative. This result shows the simulated sludge is representative of the actual sludge. (4) When the data is adjusted for differences in transmembrane pressure, the filter flux in the Actinide Removal Process is comparable to the filter flux in the bench-scale and pilot-scale testing. (5) Filter flux increased with transmembrane pressure, increased with axial velocity, and decreased with concentration in agreement with classical crossflow filtration theories