The Abell 85 BCG: a nucleated, core-less galaxy

New high-resolution r band imaging of the brightest cluster galaxy (BCG) in Abell 85 (Holm 15A) was obtained using the Gemini Multi Object Spectrograph. These data were taken with the aim of deriving an accurate surface brightness profile of the BCG of Abell 85, in particular its central region. The new Gemini data show clear evidence of a previously unreported nuclear emission that is evident as a distinct light excess in the central kiloparsec of the surface brightness profile. We find that the light profile is never flat nor does it present a downward trend towards the center of the galaxy. That is, the new Gemini data show a different physical reality from the featureless, "evacuated core" recently claimed for the Abell 85 BCG. After trying different models, we find that the surface brightness profile of the BCG of Abell 85 is best fit by a double Sersic model.Comment: Gemini web feature: Supermassive black hole that wasn't - http://gemini.edu/node/1247

AGN Jets and a Fanciful Trio of Black Holes in the Abell 85 Brightest Cluster Galaxy

A new radio map of the Abell 85 Brightest Cluster Galaxy (BCG) was obtained with the Karl G. Jansky Very Large Array. With a resolution of 002, this radio image shows two kiloparsec-scale bipolar active galactic nucleus jets emanating from the active galactic nucleus of the A85 BCG. The galaxy core appears as a single entity on the new radio map. It has been assumed that the A85 BCG contained a binary black hole in its core. However, Chandra X-ray data and the new high-resolution radio map show no evidence that the A85 BCG harbors a binary black hole. The assumption that this galaxy contains a binary black hole was based on the analysis of its optical surface brightness profile obtained under poor seeing conditions. We demonstrate how the well-known blurring effects of atmospheric seeing can mimic the effects of a binary supermassive black hole (SMBH). Likewise, SDSS J004150.75–091824.3 was postulated to be a third SMBH associated with the BCG. In the optical and X-rays, SDSS J004150.75–091824.3 is a point-like source located ~14\u27\u27 away from the nucleus of the A85 BCG. A new spectrum of SDSS J004150.75–091824.3, obtained with the 10.4 m Gran Telescopio Canarias, reveals that this source is a background quasar at a redshift of z = 1.5603 ± 0.003 and not associated in any way with the A85 cluster

Which countries are leading high-impact science in astronomy?

Recent news reports claim that China is overtaking the United States and all other countries in scientific productivity and scientific impact. A straightforward analysis of high-impact papers in astronomy reveals that this is not true in our field. In fact, the United States continues to host, by a large margin, the authors that lead high-impact papers. Moreover, this analysis shows that 90% of all high-impact papers in astronomy are led by authors based in North America and Europe. That is, only about 10% of countries in the world host astronomers that publish “astronomy’s greatest hits

Producción de etanol de lodos papeleros USANDO Kluyveromyces marxianus

RESUMEN: El lodo de papel reciclado es una materia prima promisoria para la producción de etanol. En esta investigación, nosotros primero evaluamos el efecto de la concentración de etanol, la carga de sólidos y la cristalinidad de la celulosa sobre la hidrólisis enzimática de la celulosa. También se evaluó la producción de etanol con lodo de papel mediante el proceso de sacarificación y fermentación simultanea (SSF) e hidrólisis y fermentación separada (SHF) empleando la levadura Kluyveromyces marxianus ATCC 36907. El etanol presenta un efecto inhibitorio sobre la hidrólisis de la celulosa. Una concentración de etanol de 40 g/L genera una reducción del 79 % en la producción teórica de azúcares reductores. Al incrementar la concentración de sólidos se observa una reducción en la conversión de la celulosa a azúcares reductores obteniéndose un 76 % de conversión con 9 % de sólidos. Una mayor conversión y productividad en etanol fueron alcanzadas en el proceso SSF en relación al proceso SHF en 72 horas de tratamiento. Palabras clave: Lodo papelero, etanol, Kluyveromyces marxianus, fermentación, hidrólisisABSTARCT: Recycled paper sludge is a promising raw material for ethanol production. In this study, we first evaluated the effects of ethanol concentration, solids load, and cellulose crystallinity on the enzymatic hydrolysis of cellulose to produce reducing sugars. We then evaluated the production of ethanol by either saccharification and simultaneous fermentation (SSF) or separated hydrolysis and fermentation (SHF) using the yeast Kluyveromyces marxianus ATCC 36907. We found that cellulose hydrolysis decreased as ethanol concentrations increased; at 40 g/L ethanol, the reducing sugar production was decreased by 79 %. Hydrolysis also decreased as solids load increased; at 9 % of solids, the cellulose conversion was 76 % of the stoichiometric production. The ethanol yield and cellulose conversion rate were higher with SSF as opposed to SHF processes at 72 h of treatment. Keywords: Paper sludge, ethanol, Kluyveromyces marxianus, fermentation, hydrolysi

Evaluación y mejoramiento del proceso de recuperación de solvente en la producción de carboximetilcelulosa

El proyecto “Evaluación y mejoramiento del proceso de recuperación de solvente en la producción de carboximetilcelulosa”, pretende analizar el estado actual de las etapas de recuperación de solvente (equipo recuperador CGT) y purificación de solvente (torre de destilación) en la empresa Química AMTEX S.A., y plantear posibles mejoras para el funcionamiento de estos equipos.102 P.Contenido parcial: Generalidades de la CMC -- Proceso productivo -- Molienda de celulosa -- Análisis del proceso -- Etapa de recuperación de solvente -- Etapa de purificación del solvente (Torre destilación) -- Comparación de resultados con la fase 1 del proyecto

Monitoring of the radio galaxy M 87 during a low-emission state from 2012 to 2015 with MAGIC

M87 is one of the closest (z = 0.004 36) extragalactic sources emitting at very high energies (VHE, E \u3e 100 GeV). The aim of this work is to locate the region of the VHE gamma-ray emission and to describe the observed broad-band spectral energy distribution (SED) during the low VHE gamma-ray state. The data fromM87 collected between 2012 and 2015 as part of aMAGIC monitoring programme are analysed and combined with multiwavelength data from Fermi-LAT, Chandra, HST, EVN, VLBA, and the Liverpool Telescope. The averaged VHE gamma-ray spectrum can be fitted from ∼100 GeV to ∼10 TeV with a simple power law with a photon index of (−2.41 ± 0.07), while the integral flux above 300 GeV is (1.44 ± 0.13) × 10−12 cm−2 s−1. During the campaign between 2012 and 2015, M87 is generally found in a low-emission state at all observed wavelengths. The VHE gamma-ray flux from the present 2012–2015M 87 campaign is consistent with a constant flux with some hint of variability (∼ 3 σ) on a daily time-scale in 2013. The low-state gamma-ray emission likely originates from the same region as the flare-state emission. Given the broad-band SED, both a leptonic synchrotron self-Compton and a hybrid photohadronic model reproduce the available data well, even if the latter is preferred. We note, however, that the energy stored in the magnetic field in the leptonic scenario is very low, suggesting a matter-dominated emission region

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