We present a search for an excess of neutrino interactions due to dark matter in the form of Weakly Interacting Massive Particles (WIMPs) annihilating in the galactic center or halo based on the data ...set of Super-Kamiokande-I, -II, -III and -IV taken from 1996 to 2016. We model the neutrino flux, energy, and flavor distributions assuming WIMP self-annihilation is dominant to \(\nu \overline{\nu}\), \(\mu^+\mu^-\), \(b\overline{b}\), or \(W^+W^-\). The excess is in comparison to atmospheric neutrino interactions which are modeled in detail and fit to data. Limits on the self-annihilation cross section \(\langle \sigma_{A} V \rangle\) are derived for WIMP masses in the range 1 GeV to 10 TeV, reaching as low as \(9.6 \times10^{-23}\) cm\(^3\) s\(^{-1}\) for 5 GeV WIMPs in \(b\bar b\) mode and \(1.2 \times10^{-24}\) cm\(^3\) s\(^{-1}\) for 1 GeV WIMPs in \(\nu \bar \nu\) mode. The obtained sensitivity of the Super-Kamiokande detector to WIMP masses below several tens of GeV is the best among similar indirect searches to date.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
496.
XMM-Newton Observations of Red AGNs Wilkes, B. J; Pounds, K. A; Schmidt, G. D ...
The Astrophysical journal,
11/2005, Volume:
634, Issue:
1
Journal Article
Peer reviewed
Open access
XMM-Newton spectra of five red 2MASS active galactic nuclei (AGNs), selected from a sample observed by Chandra to be relatively X-ray bright and to cover a range of hardness ratios, confirm the ...presence of substantial absorbing material in three sources with optical classifications ranging from type 1 to type 2. A flat (hard) power-law continuum is observed in the other two. The combination of X-ray absorption and broad optical emission lines suggests either a small (nuclear) absorber or a favored viewing angle so as to cover the X-ray source but not the broad emission-line region (BELR). A soft excess is detected in all three type 1 sources. We speculate that this may arise in an extended region of ionized gas, perhaps linked to the polarized (scattered) optical light present in these sources. The spectral complexity revealed by XMM-Newton emphasizes the limitations of the low-S/N Chandra data. The new results strengthen our earlier conclusions that the observed X-ray continua of red AGNs are unusually hard at energies >2 keV. Their observed spectra are consistent with contributing significantly to the missing hard or absorbed population of the cosmic X-ray background (CXRB), although their intrinsic power-law slopes are typical of broad-line (type 1) AGNs ( 6 1.7-1.9). This suggests that the missing X-ray-absorbed CXRB population may include type 1 AGNs or QSOs in addition to the type 2 AGNs generally assumed.
Lack of viral load monitoring of ART is known to be associated with slower switch from a failing regimen and thereby higher prevalence of MDR HIV-1. Many countries have continued to use thymidine ...analogue drugs despite recommendations to use tenofovir in combination with a cytosine analogue and NNRTI as first-line ART. The effect of accumulated thymidine analogue mutations (TAMs) on phenotypic resistance over time has been poorly characterized in the African setting.
A retrospective analysis of individuals with ongoing viral failure between weeks 48 and 96 in the NORA (Nevirapine OR Abacavir) study was conducted. We analysed 36 genotype pairs from weeks 48 and 96 of first-line ART (14 treated with zidovudine/lamivudine/nevirapine and 22 treated with zidovudine/lamivudine/abacavir). Phenotypic drug resistance was assessed using the Antivirogram assay (v. 2.5.01, Janssen Diagnostics).
At 96 weeks, extensive TAMs (≥3 mutations) were present in 50% and 73% of nevirapine- and abacavir-treated patients, respectively. The mean (SE) number of TAMs accumulating between week 48 and week 96 was 1.50 (0.37) in nevirapine-treated participants and 1.82 (0.26) in abacavir-treated participants. Overall, zidovudine susceptibility of viruses was reduced between week 48 geometric mean fold change (FC) 1.3 and week 96 (3.4, P = 0.01). There was a small reduction in tenofovir susceptibility (FC 0.7 and 1.0, respectively, P = 0.18).
Ongoing viral failure with zidovudine-containing first-line ART is associated with rapidly increasing drug resistance that could be mitigated with effective viral load monitoring.
We report a measurement of the \(\nu_{\mu}\)-nucleus inclusive charged current cross section (=\(\sigma^{cc}\)) on iron using data from exposed to the J-PARC neutrino beam. The detector consists of ...14 modules in total, which are spread over a range of off-axis angles from 0\(^\circ\) to 1.1\(^\circ\). The variation in the neutrino energy spectrum as a function of the off-axis angle, combined with event topology information, is used to calculate this cross section as a function of neutrino energy. The cross section is measured to be \(\sigma^{cc}(1.1\text{ GeV}) = 1.10 \pm 0.15\) \((10^{-38}\text{cm}^2/\text{nucleon})\), \(\sigma^{cc}(2.0\text{ GeV}) = 2.07 \pm 0.27\) \((10^{-38}\text{cm}^2/\text{nucleon})\), and \(\sigma^{cc}(3.3\text{ GeV}) = 2.29 \pm 0.45\) \((10^{-38}\text{cm}^2/\text{nucleon})\), at energies of 1.1, 2.0, and 3.3 GeV, respectively. These results are consistent with the cross section calculated by the neutrino interaction generators currently used by T2K. More importantly, the method described here opens up a new way to determine the energy dependence of neutrino-nucleus cross sections.
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