3,156 research outputs found
New flaring of an ultraluminous X-ray source in NGC 1365
We have studied a highly variable ultraluminous X-ray source (ULX) in the
Fornax galaxy NGC 1365, with a series of 12 Chandra and XMM-Newton observations
between 2002 and 2006. In 2006 April, the source peaked at a luminosity ~ 3 x
10^{40} erg/s in the 0.3-10 keV band (similar to the maximum luminosity found
by ASCA in 1995), and declined on an e-folding timescale ~ 3 days. The X-ray
spectrum is always dominated by a broad power-law-like component. When the
source is seen at X-ray luminosities ~ 10^{40} erg/s, an additional soft
thermal component (which we interpret as emission from the accretion disk)
contributes ~ 1/4 of the X-ray flux; when the luminosity is higher, ~ 3 x
10^{40} erg/s, the thermal component is not detected and must contribute < 10%
of the flux. At the beginning of the decline, ionized absorption is detected
around 0.5-2 keV; it is a possible signature of a massive outflow. The
power-law is always hard, with a photon index Gamma ~ 1.7 (and even flatter at
times), as is generally the case with bright ULXs. We speculate that this
source and perhaps most other bright ULXs are in a high/hard state: as the
accretion rate increases well above the Eddington limit, more and more power is
extracted from the inner region of the inflow through non-radiative channels,
and is used to power a Comptonizing corona, jet or wind. The observed thermal
component comes from the standard outer disk; the transition radius between
outer standard disk and Comptonizing inner region moves further out and to
lower disk temperatures as the accretion rate increases. This produces the
observed appearance of a large, cool disk. Based on X-ray luminosity and
spectral arguments, we suggest that this accreting black hole has a likely mass
~ 50-150 Msun (even without accounting for possible beaming).Comment: 14 pages, to appear in MNRA
XMM-Newton observations of the spiral galaxy M74 (NGC 628)
The face-on spiral galaxy M74 (NGC 628) was observed by XMM on 2002 February
2. In total, 21 sources are found in the inner 5' from the nucleus (after
rejection of a few sources associated to foreground stars). Hardness ratios
suggest that about half of them belong to the galaxy. The higher-luminosity end
of the luminosity function is fitted by a power-law of slope -0.8. This can be
interpreted as evidence of ongoing star formation, in analogy with the
distributions found in disks of other late-type galaxies. A comparison with
previous Chandra observations reveals a new ultraluminous X-ray transient (L_x
\~ 1.5 x 10^39 erg/s in the 0.3--8 keV band) about 4' North of the nucleus. We
find another transient black-hole candidate (L_x ~ 5 x 10^38 erg/s) about 5'
North-West of the nucleus. The UV and X-ray counterparts of SN 2002ap are also
found in this XMM observation.Comment: submitted to ApJL. Based on publicly available data, see
http://xmm.vilspa.esa.es/external/xmm_news/items/sn_2002_ap/index.shtm
Composición y Método Cinético de Medición de la Actividad Lipasa
Número de publicación: ES2358029 A1 (05.05.2011) También publicado como: ES2358029 B2 (23.03.2012 Número de Solicitud: Consulta de Expedientes OEPM (C.E.O.) P200902117(20.10.2009)La presente invención pertenece al campo de las composiciones químicas utilizadas en métodos de determinación de actividad enzimática. En particular, la presente invención se encuadra en los métodos cinéticos de determinación de la actividad lipasa que utilizan sustratos sintéticos.Universidad de Almerí
Celdilla de digestión-Lixiviación con membrana semipermeable, sistema de cerrado hermético y de control de temperatura
Número de publicación: ES2524521 A1 (09.12.2014) También publicado como: ES2524521 B1 (13.10.2015)ES2524521 B8 (13.05.2016) Número de Solicitud: Consulta de Expedientes OEPM (C.E.O.) P201201027 (08.10.2012)La invención es una celdilla de digestión-lixiviación con membrana semipermeable, sistema de cerrado hermético y de control de temperatura que es un dispositivo para pruebas de digestibilidad y lixiviación de moléculas o iones a nivel laboratorio. La invención es un diseño novedoso que permite mantener aislada la cámara interna (donde se realiza la digestión-lixiviación de materiales) de la cámara externa (donde se reciben los productos de la digestión-lixiviación) conectadas exclusivamente a través de la membrana semipermeable, de tamaño de poro intercambiable, para el paso de las moléculas o iones de tamaño deseado. La celdilla contiene un dispositivo que permite mantener un control de la temperatura en el interior de la cámara interna. Las aplicaciones de la celdilla están en laboratorios académicos o de investigación (empresas, centros de investigación, institutos, Universidades) para la realización de pruebas de digestibilidad in vitro de macromoléculas o de lixiviación de moléculas o iones.Universidad de Almerí
Crianza real y clientelismo nobiliario: los Bobadilla, una familia de la oligarquía granadina
The Bobadilla Family represents a wonderful example of the numerous bureaucratic families -in this case of judeoconverso origin- which increased in wealth and social standing under the auspices of the Crown during the reign of the Ferdinand and Isabella. From a prior position of local importance in Sego- via, the Bobadilla Family assisted in the conquest of the Grenadine Emirate and they received substantial mercedes in the form of land within the Grena¬dine Kingdom; these properties were further increased by means of purchases and usurpations. Along with their wealth, meticulously analyzed in this project, their social ascent was due to their cióse affiliation to the Counts of Tendilla, their relatives and protectors, with whom they collaborated in the difficult, but fruitful, governing of the recently-conquered territory.La familia Bobadilla representa un maravilloso ejemplo de las numerosas familias burocráticas -en este caso de origen judeoconverso- que se incrementaron en riqueza y posición social bajo los auspicios de la Corona durante el reinado de Fernando e Isabel. Desde una posición anterior de importancia local en Segovia, la familia Bobadilla asistió en la conquista del Emirato Granadino y recibió mercedes sustanciales en forma de tierras dentro del Reino de Grenada; estas propiedades se incrementaron aún más por medio de compras y usurpaciones. Junto a su riqueza, meticulosamente analizada en este proyecto, su ascenso social se debió a su cióse afiliación a los Condes de Tendilla, sus familiares y protectores, con quienes colaboraron en el difícil, pero fructífero, gobierno del territorio recién conquistado
Dynamics of Annihilation II: Fluctuations of Global Quantities
We develop a theory for fluctuations and correlations in a gas evolving under
ballistic annihilation dynamics. Starting from the hierarchy of equations
governing the evolution of microscopic densities in phase space, we
subsequently restrict to a regime of spatial homogeneity, and obtain explicit
predictions for the fluctuations and time correlation of the total number of
particles, total linear momentum and total kinetic energy. Cross-correlations
between these quantities are worked out as well. These predictions are
successfully tested against Molecular Dynamics and Monte-Carlo simulations.
This provides strong support for the theoretical approach developed, including
the hydrodynamic treatment of the spectrum of the linearized Boltzmann
operator. This article is a companion paper to arXiv:0801.2299 and makes use of
the spectral analysis reported there.Comment: 19 page
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