433 research outputs found
Optical detection of the radio supernova SN 2000ft in the circumnuclear region of the luminous infrared galaxy NGC 7469
SN 2000ft is detected in two independent Planetary Camera images (F547W and
F814W) taken May 13, 2000, about two months before the predicted date of the
explosion (July 19, 2000), based on the analysis of its radio light evolution
by Alberdi and collaborators. The apparent optical magnitudes and red color of
SN 2000ft indicate that it is observed through an extinction of at least A=
3.0 magnitudes. The extinction corrected lower limit to the absolute visual
magnitude (M 18.0), identifies SN 2000ft as a luminous supernova
in the optical, as other luminous radio supernovae before. SN 2000ft exploded
in a region located at only 0.1 arcsec (i.e. 34 +/- 3 pc) west of a faint
cluster (C24). No parent cluster is identified within the detection limits of
the HST short exposures. The unambiguous detection of SN 2000ft in the visual
shows that multi-epoch sub-arcsecond (FWHM less than 0.1 arcsec) optical
imaging is also a valid tool that should be explored further to detect
supernovae in the dusty (circum)nuclear regions of (U)LIRGs
Mid-Infrared T-ReCS Spectroscopy of Local LIRGs
We present T-ReCS high spatial resolution N-band (8-13 micron) spectroscopy of the central regions (a few kpc) of 3 local LIRGs. The nuclear spectra show deep 9.7 micron silicate absorption feature and the high ionization [SIV]10.5 micron emission line, consistent with their optical classification as AGN. The two LIRGs with unresolved mid-IR emission do not show PAH emission at 11.3 micron in their nuclear spectra. The spatially resolved mid-IR spectroscopy of NGC 5135 allows us to separate out the spectra of the Seyfert nucleus, an HII region, and the diffuse region between them on scales of less than 2.5 arcsec ~ 600 pc. The diffuse region spectrum is characterized by strong PAH emission with almost no continuum, whereas the HII region shows PAH emission with a smaller equivalent width as well as [NeII]12.8 micron line
Mid-infrared imaging- and spectro-polarimetric subarcsecond observations of NGC 1068
We present sub-arcsecond 7.513 m imaging- and spectro-polarimetric
observations of NGC 1068 using CanariCam on the 10.4-m Gran Telescopio
CANARIAS. At all wavelengths, we find:
(1) A 90 60 pc extended polarized feature in the northern ionization
cone, with a uniform 44 polarization angle. Its polarization
arises from dust and gas emission in the ionization cone, heated by the active
nucleus and jet, and further extinguished by aligned dust grains in the host
galaxy. The polarization spectrum of the jet-molecular cloud interaction at
24 pc from the core is highly polarized, and does not show a silicate
feature, suggesting that the dust grains are different from those in the
interstellar medium.
(2) A southern polarized feature at 9.6 pc from the core. Its
polarization arises from a dust emission component extinguished by a large
concentration of dust in the galaxy disc. We cannot distinguish between dust
emission from magnetically aligned dust grains directly heated by the jet close
to the core, and aligned dust grains in the dusty obscuring material
surrounding the central engine. Silicate-like grains reproduce the polarized
dust emission in this feature, suggesting different dust compositions in both
ionization cones.
(3) An upper limit of polarization degree of 0.3 per cent in the core. Based
on our polarization model, the expected polarization of the obscuring dusty
material is 0.1 per cent in the 813 m wavelength range. This
low polarization may be arising from the passage of radiation through aligned
dust grains in the shielded edges of the clumps.Comment: 17 pages, 10 figures, accepted for publication at MNRA
Multispectral images of peach related to firmness and maturity at harvest
wo multispectral maturity classifications for red soft-flesh peaches (‘Kingcrest’, ‘Rubyrich’ and ‘Richlady’ n = 260) are proposed and compared based on R (red) and R/IR (red divided by infrared) images obtained with a three CCD camera (800 nm, 675 nm and 450 nm). R/IR histograms were able to correct the effect of 3D shape on light reflectance and thus more Gaussian histograms were produced than R images. As fruits ripened, the R/IR histograms showed increasing levels of intensity. Reference measurements such as firmness and visible spectra also varied significantly as the fruit ripens, firmness decreased while reflectance at 680 nm increased (chlorophyll absorption peak)
Intra-abdominal pulmonary secuestration as an exceptional cause of abdominal mass in the adult
AbstractINTRODUCTIONPulmonary sequestration (PS) is an extremely rare malformation defined as a portion of lung tissue isolated from the pulmonary system. PSs are classified into intralobar type and intra-abdominal PS that represents only 2.5% of cases. There are 20 cases of PS reported in adults and only two were managed by laparoscopic approach. We report a case of intra-abdominal PS mimicking a gastroesophageal duplication cyst in an adult. Besides its rarity, this is the first intra-abdominal PS in an adult managed by an anterior laparoscopic approach.PRESENTATION OF CASEA 60-year-old female patient had had epigastric and left upper quadrant pain for several days. Physical examination was normal. Image test were consistent with a gastroesophageal duplication. The patient was taken to the operating room for laparoscopic exploration and resection. The pathological diagnosis was extralobar pulmonary sequestration.DISCUSSIONLess than 20 cases of PS have been reported in adults and only two cases were managed by a lateral laparoscopic approach. In contrast to these reports, we used an anterior approach due to the GEJ suspected origin of the mass.CONCLUSIONExtralobar intra-abdominal PS is an extremely rare condition during adulthood but this diagnosis should be included in the differential diagnosis of a left-sided suprarenal mass. Due to the difficulty in achieving a definitive preoperative diagnosis, surgery is recommended. Laparoscopic resection is safe and effective but careful preoperative imaging studies are recommended in order to plan the most suitable approach
Analysis of the concentration of emissions from the Spanish fleet of tugboats
At present, the sensitivity of society towards emissions in commercial maritime ports is increasing, which is reflected in the large number of studies on the control of emissions in them, perhaps because the most important commercial ports are located in cities with high population density. The objective of this work was to determine the greenhouse gas emissions caused by the activity of the Spanish tugboat fleet, studying the tugboat fleet of the eleven autonomous coastal Spanish communities from 2004 to 2017 and their impact on the carbon footprint of the country?s shipping sector. To do this, the methodology used by the International Maritime Organization for merchant ships to estimate the emissions of a tugboat fleet is formalized, and Gini concentration index methodology was applied to the concentration of emissions from this fleet. This has made it possible to obtain results on the distribution of the concentration of emissions from Spanish ports by region, age, and size, as well as to establish the profile of the tugboat port that pollutes the most and its carbon footprint. One of the results is that in the period analyzed, the concentration of emissions from the Spanish tugboat fleet increased if we looked at its distribution by region, and decreased if we look at its distribution by age and size. This is because tugboat activity was very different by region; however, their characteristics related to age and size evolved in a more homogeneous way
Lepton flavor violating Higgs boson decays from massive seesaw neutrinos
Lepton flavor violating Higgs boson decays are studied within the context of
seesaw models with Majorana massive neutrinos. Two models are considered: The
SM-seesaw, with the Standard Model Particle content plus three right handed
neutrinos, and the MSSM-seesaw, with the Minimal Supersymmetric Standard Model
particle content plus three right handed neutrinos and their supersymmetric
partners. The widths for these decays are derived from a full one-loop
diagrammatic computation in both models, and they are analyzed numerically in
terms of the seesaw parameters, namely, the Dirac and Majorana mass matrices.
Several possible scenarios for these mass matrices that are compatible with
neutrino data are considered. In the SM-seesaw case, very small branching
ratios are found for all studied scenarios. These ratios are explained as a
consequence of the decoupling behaviour of the heavy right handed neutrinos. In
contrast, in the MSSM-seesaw case, sizeable branching ratios are found for some
of the leptonic flavor violating decays of the MSSM neutral Higgs bosons and
for some choices of the seesaw matrices and MSSM parameters. The relevance of
the two competing sources of lepton flavor changing interactions in the
MSSM-seesaw case is also discussed. The non-decoupling behaviour of the
supersymmetric particles contributing in the loop-diagrams is finally shown.Comment: 44pgs. Version to appear in Phys.Rev.
Painlev\'e-Gullstrand synchronizations in spherical symmetry
A Painlev\'e-Gullstrand synchronization is a slicing of the space-time by a
family of flat spacelike 3-surfaces. For spherically symmetric space-times, we
show that a Painlev\'e-Gullstrand synchronization only exists in the region
where , being the curvature radius of the isometry group
orbits (-spheres). This condition says that the Misner-Sharp gravitational
energy of these 2-spheres is not negative and has an intrinsic meaning in terms
of the norm of the mean extrinsic curvature vector. It also provides an
algebraic inequality involving the Weyl curvature scalar and the Ricci
eigenvalues. We prove that the energy and momentum densities associated with
the Weinberg complex of a Painlev\'e-Gullstrand slice vanish in these curvature
coordinates, and we give a new interpretation of these slices by using
semi-metric Newtonian connections. It is also outlined that, by solving the
vacuum Einstein's equations in a coordinate system adapted to a
Painlev\'e-Gullstrand synchronization, the Schwarzschild solution is directly
obtained in a whole coordinate domain that includes the horizon and both its
interior and exterior regions.Comment: 16 page
On the difference of torus geometry between hidden and non-hidden broad line active galactic nuclei
We present results from the fitting of infrared (IR) spectral energy
distributions of 21 active galactic nuclei (AGN) with clumpy torus models. We
compiled high spatial resolution (-- arcsec) mid-IR -band
spectroscopy, -band imaging and nuclear near- and mid-IR photometry from the
literature. Combining these nuclear near- and mid-IR observations, far-IR
photometry and clumpy torus models, enables us to put constraints on the torus
properties and geometry. We divide the sample into three types according to the
broad line region (BLR) properties; type-1s, type-2s with scattered or hidden
broad line region (HBLR) previously observed, and type-2s without any published
HBLR signature (NHBLR). Comparing the torus model parameters gives us the first
quantitative torus geometrical view for each subgroup. We find that NHBLR AGN
have smaller torus opening angles and larger covering factors than those of
HBLR AGN. This suggests that the chance to observe scattered (polarized) flux
from the BLR in NHBLR could be reduced by the dual effects of (a) less
scattering medium due to the reduced scattering volume given the small torus
opening angle and (b) the increased torus obscuration between the observer and
the scattering region. These effects give a reasonable explanation for the lack
of observed HBLR in some type-2 AGN.Comment: 13 pages, 5 figures, accepted for publication in Ap
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