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An Extended Nebulosity Of Highly Ionized-Gas In The Sbo Seyfert-Galaxy NGC-3516 - Detection And Study Of The Physical Conditions Of The Gas
NSF AST 73-05312Astronom
The Steep Spectrum Quasar PG1404+226 with ASCA, HST and ROSAT
(abridged) We present and discuss our observations of the NL quasar
PG1404+226 with ASCA and HST, and a re-analysis of our earlier observations
with ROSAT. The soft X-ray spectrum is very steep and displays an absorption
feature (edge or line at ~1.1 keV). We have applied a variety of models to the
ASCA and ROSAT spectra without finding a completely satisfactory fit, and the
identification of the edge remains uncertain. A satisfactory fit of the ASCA
spectrum assuming that the edge is produced by highly ionized iron (using the
code absori in XSPEC) is obtained with an overabundance of iron by a factor >
25 compared to solar, a suggestion supported by the extremely high equivalent
width of the Fe K_alpha line at 6.4 keV. A warm absorber model fitting the
absorption feature with NeVII-NeX edges and assuming a peculiar oxygen/neon
abundance ratio is consistent with the ROSAT data but not the ASCA data.
Finally, it is also possible that the observed edge is caused by a OVIII or
OVII edge or line, blueshifted by z_abs=0.2 to 0.5 depending on the specific
identification, as has been suggested previously for 2 other NL quasars, but
there are no other features in the UV and X-ray spectra in support of this
suggestion. Two systems of UV absorption lines, one nearly at rest in the
source frame, the other blueshifted by ~1900 km/s are identified in the HST/FOS
spectra.
Photoionization models indicate that the UV absorption and the ~1 keV
absorption are probably caused by absorbers with different physical conditions.
PG1404+226 is one more case of AGN where both UV and X-ray absorption features
are detected, thereby increasing further the significance of the previously
noted statistical association of the two types of absorbers.Comment: 11 pages, A&A in pres
Recommendations of the LHC Dark Matter Working Group: Comparing LHC searches for heavy mediators of dark matter production in visible and invisible decay channels
Weakly-coupled TeV-scale particles may mediate the interactions between
normal matter and dark matter. If so, the LHC would produce dark matter through
these mediators, leading to the familiar "mono-X" search signatures, but the
mediators would also produce signals without missing momentum via the same
vertices involved in their production. This document from the LHC Dark Matter
Working Group suggests how to compare searches for these two types of signals
in case of vector and axial-vector mediators, based on a workshop that took
place on September 19/20, 2016 and subsequent discussions. These suggestions
include how to extend the spin-1 mediated simplified models already in
widespread use to include lepton couplings. This document also provides
analytic calculations of the relic density in the simplified models and reports
an issue that arose when ATLAS and CMS first began to use preliminary numerical
calculations of the dark matter relic density in these models.Comment: 19 pages, 4 figures; v2: author list and LaTeX problem fixe
Cardiorespiratory fitness, physical activity, and fatigue three months after first-ever ischemic stroke
Background: Research on cardiorespiratory fitness (CRF) in relation to physical activity (PA) and fatigue after stroke is limited. Increased knowledge of interrelationships between these factors can help optimize rehabilitation strategies and improve health-outcomes.
Objectives: We aimed to: 1) evaluate CRF, PA, and fatigue, 2) characterize patients with impaired versus non-impaired CRF, and 3) examine associations of CRF with PA and fatigue, three months after first-ever ischemic stroke.
Methods: In this cross-sectional study CRF was measured as peak oxygen uptake (VO2peak) by cardiopulmonary exercise testing. PA was measured using accelerometers. Fatigue was assessed with the 7-item Fatigue Severity Scale (FSS).
Results: The sample (n=74, mean age 64±13 years, 36% women) had a mean VO2peak of 27.0±8.7 (86% of predicted). Fifty-one percent met the World Health Organization’s recommendation of ≥150 min of moderate PA/week. Mean steps-per-day was 9316±4424 (113% of predicted). Thirty-five percent of the sample had moderate-to-high fatigue (FSS≥4), mean FSS score was 3.2±1.8. Patients with impaired CRF (VO2peak<80% of predicted) had higher body-fat-percent (p<0.01), less moderate-to-vigorous PA (MVPA) (p<0.01) and a trend toward higher fatigue (p=0.053) compared to the non-impaired. Backward regression analysis showed that higher CRF was associated with more MVPA (unstandardized beta [95% CI]: 0.38 [0.15, 0.63], p=0.002) and less fatigue (unstandardized beta [95% CI]: -3.9 [-6.4, -1.6], p=0.004).
Conclusions: Stroke patients had lower CRF compared to reference values. Impaired CRF was mainly related to overweight. Higher CRF was associated with more MVPA and less fatigue. Exercise after stroke may be especially beneficial for patients with impaired CRF.publishedVersio
Measurement of the forward Z boson production cross-section in pp collisions at TeV
A measurement of the production cross-section of Z bosons in pp collisions at TeV is presented using dimuon and dielectron final states in LHCb data. The cross-section is measured for leptons with pseudorapidities in the range , transverse momenta GeV and dilepton invariant mass in the range GeV. The integrated cross-section from averaging the two final states is \begin{equation*}\sigma_{\text{Z}}^{\ell\ell} = 194.3 \pm 0.9 \pm 3.3 \pm 7.6\text{ pb,}\end{equation*} where the first uncertainty is statistical, the second is due to systematic effects, and the third is due to the luminosity determination. In addition, differential cross-sections are measured as functions of the Z boson rapidity, transverse momentum and the angular variable
Les droits disciplinaires des fonctions publiques : « unification », « harmonisation » ou « distanciation ». A propos de la loi du 26 avril 2016 relative à la déontologie et aux droits et obligations des fonctionnaires
The production of tt‾ , W+bb‾ and W+cc‾ is studied in the forward region of proton–proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98±0.02 fb−1 . The W bosons are reconstructed in the decays W→ℓν , where ℓ denotes muon or electron, while the b and c quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions.The production of , and is studied in the forward region of proton-proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98 0.02 \mbox{fb}^{-1}. The bosons are reconstructed in the decays , where denotes muon or electron, while the and quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions
Testosterone, Sex Hormone-Binding Globulin and the Metabolic Syndrome in Men: An Individual Participant Data Meta-Analysis of Observational Studies
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