1,430 research outputs found
Optical and X-ray Properties of the Swift BAT-detected AGN
The Swift Gamma-Ray Burst satellite has detected a largely unbiased towards
absorption sample of local () AGN, based solely on their
14--195 keV flux. In the first 9 months of the survey, 153 AGN sources were
detected. The X-ray properties in the 0.3--10 keV band have been compiled and
presented based on analyses with XMM-Newton, Chandra, Suzaku, and the Swift XRT
(Winter et al. 2009). Additionally, we have compiled a sub-sample of sources
with medium resolution optical ground-based spectra from the SDSS or our own
observations at KPNO. In this sample of 60 sources, we have classified the
sources using standard emission line diagnostic plots, obtained masses for the
broad line sources through measurement of the broad H emission line, and
measured the [OIII] 5007\AA luminosity of this sample. Based on continuum fits
to the intrinsic absorption features, we have obtained clues about the stellar
populations of the host galaxies. We now present the highlights of our X-ray
and optical studies of this unique sample of local AGNs, including a comparison
of the 2--10 keV and 14--195 keV X-ray luminosities with the [OIII] 5007\AA
luminosity and the implications of our results towards measurements of
bolometric luminosities.Comment: 4 pages, 2 figures, to appear in proceedings for 'X-ray Astronomy
2009', Bologna 09/2009, AIP Conference Series, Eds. A. Comastri, M. Cappi, L.
Angelin
Visual rehabilitation in combined surgical procedures: bridging two eye poles for better vision
Augenzentrum Nymphenburger Höfe and Augenklinik Herzog Carl Theodor, München, GermanyDepartment of Ophthalmology, University of Heidelberg, Heidelberg, GermanyDepartment of Ophthalmology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Republic of KoreaCleveland Clinic Foundation, Cole Eye Institute, Cleveland, OH, USADepartment of Ophthalmology, Universidade Federal de São Paulo, São Paulo, SP, BrazilDepartment of Ophthalmology, Tan Tock Seng Hospital, SingaporeDepartment of Ophthalmology, Universidade Federal de São Paulo, São Paulo, SP, BrazilWeb of Scienc
[O III] and X-ray Properties of a Complete Sample of Hard X-ray Selected AGNs in the Local Universe
We study the correlation between the [O III] and X-ray
luminosities of local Active Galactic Nuclei (AGNs), using a complete, hard
X-ray ( keV) selected sample in the Swift/BAT 9-month catalog. From our
optical spectroscopic observations at the South African Astronomical
Observatory and the literature, a catalog of [O III] line flux
for all 103 AGNs at Galactic latitudes of is complied.
Significant correlations with intrinsic X-ray luminosity () are
found both for observed () and extinction-corrected () luminosities, separately for X-ray unabsorbed and absorbed
AGNs. We obtain the regression form of and from the whole sample. The absorbed AGNs with low
(0.5\%) scattering fractions in soft X-rays show on average smaller and ratios than the
other absorbed AGNs, while those in edge-on host galaxies do not. These results
suggest that a significant fraction of this population are buried in tori with
small opening angles. By using these vs.
correlations, the X-ray luminosity function of local AGNs (including Compton
thick AGNs) in a standard population synthesis model gives much better
agreement with the [O III] luminosity function derived from the
Sloan Digital Sky Survey than previously reported. This confirms that hard
X-ray observations are a very powerful tool to find AGNs with high
completeness.Comment: 14 pages including 11 figures and 3 tables, accepted for publication
in ApJ. In this manuscript, the observed 14-195 keV luminosities in Table 1
have been corrected to be exactly the same as in the original Swift/BAT
9-month catalog. Accordingly, Figures 2(a) and 3(a) and a part of Tables 2
and 3 have been updated. The changes from the previous version are small and
do not affect the tex
The Transient Dendritic Solidification Experiment (TDSE)
The study of steady-state dendritic growth has both validated many element of transport phenomena in dendritic growth, and yielded many new insights. Further development in simulation and modeling are needed, as is further understanding of the role of selection or scaling in dendritic growth. The TDSE contributes to the further study of dendritic phenomena by carefully measuring and modeling transient effects on dendritic growth. The major challenge encountered in measuring and analyzing the transient behavior of isothermal dendrites is defining precisely the initial conditions from which or to which the dendrite evolves. Our proposed pressure-mediated TDSE microgravity experiment, obviates this difficulty, because the transient occurs between two well-characterized steady-states, rather than between an ill-defined initial state and the final steady state. The major results expected are unique data on transient behavior that will extend the scientific bounds from the now well-understood thermal effects, and provide insight into interfacial dynamics where open questions remain
THE EFFECT OF ROAD CAMBER ON RUNNING KINEMATICS
Camber, or the crown of roads used for drainage purposes, has been implicated as a cause of overuse injuries, including iliotibial band syndrome, in runners. The purpose of this investigation was to study the effects of varying degrees of simulated road camber and different running velocities on lower extremity kinematics. Using three-dimensional motion analysis, bilateral hip, knee, and ankle angles of 5 injury-free recreational runners were investigated. Subjects were videotaped while running on level and variable cambered surfaces at 6.0 and 7.0 mph. Post-hoc analysis found significant differences between right and left limbs between the right knee at toe off condition 1, 7.0 mph compared to right knee at toe off condition 2, 7.0 mph (
Consequences of sexual harassment in sport for female athletes
Sexual harassment research was first undertaken in the workplace and educational settings. Research on sexual harassment in sport is scarce but has grown steadily since the mid-1980s. Even so, very little is known about the causes and/or characteristics and/or consequences of sexual harassment in sport settings. This article reports on the findings from interviews with 25 elite female athletes in Norway who indicated in a prior survey (N =572) that they had experienced sexual harassment from someone in sport. The consequences of the incidents of sexual harassment that were reported were mostly negative, but some also reported that their experiences of sexual harassment had had no consequences for them. “Thinking about the incidents”, a “destroyed relationship to the coach”, and “more negative view of men in general” were the most often negative consequences mentioned. In addition, a surprising number had chosen to move to a different sport or to drop out of elite sport altogether because of the harassment
Metabolism of hexachlorobenzene in humans: association between serum levels and urinary metabolites in a highly exposed population.
Serum and urine from 100 subjects of a general population highly exposed to airborne hexachlorobenzene (HCB) were analyzed to obtain new insights into the metabolism of this ubiquitous compound. HCB was detected in all serum samples with concentrations ranging between 1.1 and 953 ng/ml. The major known metabolites of HCB were investigated in urine collected over 24 hr. Pentachlorophenol (PCP) was detected in all urines with values ranging between 0.58 and 13.9 micrograms excreted in 24 hr [mean +/- standard deviation (SD), 2.52 +/- 2.05; geometric mean, 2.05]. A sulfur derivative that, after hydrolysis, yielded pentachlorobenzenethiol (PCBT) could also be identified and quantified in all the urines with values ranging between 0.18 and 84.0 micrograms of PCBT excreted in 24 hr (mean +/- SD, 3.47 +/- 10.8; geometric mean, 1.39). The sulfur derivative assessed as PCBT appeared to be the main metabolite, with urinary concentrations surpassing those of PCP in the subjects with higher HCB accumulation (HCB in serum > 32 ng/ml). PCBT concentration in urine collected over 24 hr showed a very strong association with HCB concentration in serum; the association was stronger in males than in females. An increase of 1 ng/ml of HCB in serum led to an increase of 2.12 micrograms of PCBT excreted in urine collected over 24 hr in males (95% CI, 1.82-2.44) and to an increase of 0.67 microgram of PCBT in females (CI, 0.33-1.09). A weaker association was found between PCP in urine and HCB in serum, which was only statistically significant in males (an increase of 1 ng/ml of HCB in serum led to an increase of 0.63 microgram of PCP excreted in urine collected over 24 hr; (CI, 0.34-0.95). These results show that the formation of the cysteine conjugate is a quantitatively more important metabolic pathway in humans than the formation of PCP. Moreover, the association found suggests that PCBT is a good urinary marker of HCB internal dose and glutathione-mediated metabolism
Optical, near-IR and sub-mm IFU Observations of the nearby dual AGN Mrk 463
We present optical and near-IR Integral Field Unit (IFU) and ALMA band 6
observations of the nearby dual Active Galactic Nuclei (AGN) Mrk 463. At a
distance of 210 Mpc, and a nuclear separation of 4 kpc, Mrk 463 is an
excellent laboratory to study the gas dynamics, star formation processes and
supermassive black hole (SMBH) accretion in a late-stage gas-rich major galaxy
merger. The IFU observations reveal a complex morphology, including tidal
tails, star-forming clumps, and emission line regions. The optical data, which
map the full extent of the merger, show evidence for a biconical outflow and
material outflowing at 600 km s, both associated with the Mrk 463E
nucleus, together with large scale gradients likely related to the ongoing
galaxy merger. We further find an emission line region 11 kpc south of
Mrk 463E that is consistent with being photoionized by an AGN. Compared to the
current AGN luminosity, the energy budget of the cloud implies a luminosity
drop in Mrk 463E by a factor 3-20 over the last 40,000 years. The ALMA
observations of CO(2-1) and adjacent 1mm continuum reveal the presence
of 10M in molecular gas in the system. The molecular gas
shows velocity gradients of 800 km/s and 400 km/s around the Mrk
463E and 463W nuclei, respectively. We conclude that in this system the infall
of 100s /yr of molecular gas is in rough balance with the
removal of ionized gas by a biconical outflow being fueled by a relatively
small, 0.01% of accretion onto each SMBH.Comment: Accepted by The Astrophysical Journal, 23 pages, 19 figure
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