3,104 research outputs found

    Detecting interactions between dark matter and photons at high energy e+e−e^+e^- colliders

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    We investigate the sensitivity to the effective operators describing interactions between dark matter particles and photons at future high energy e+e−e^+e^- colliders via the \gamma+ \slashed{E} channel. Such operators could be useful to interpret the potential gamma-ray line signature observed by the Fermi-LAT. We find that these operators can be further tested at e+e−e^+ e^- colliders by using either unpolarized or polarized beams. We also derive a general unitarity condition for 2→n2 \to n processes and apply it to the dark matter production process e+e−→χχγe^+e^-\to\chi\chi\gamma.Comment: 13 pages, 8 figure

    Primordial black holes from an inflationary potential valley

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    Primordial black holes (PBHs) could be formed if large perturbations are generated on small scales in inflation. We study a toy inflation model with a local minimum. The curvature perturbations are enhanced when the inflaton passes through the local minimum, with more efficient amplification rate than that of quasi-inflection point inflation, leading to the production of PBHs on small scales. The PBHs could comprise the total dark matter in the mass window 101610^{16}--102010^{20}g.Comment: 7 pages,4 figure

    Integral and Rxte/Asm Observations on Igr J17098-3628

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    To probe further the possible nature of the unidentified source IGR J17098-3628, we have carried out a detailed analysis of its long-term time variability as monitored by RXTE/ASM, and of its hard X-ray properties as observed by INTEGRAL. INTEGRAL has monitored this sky region over years and significantly detected IGR J17098-3628 only when the source was in this dubbed active state. In particular, at ≥\ge 20 keV, IBIS/ISGRI caught an outburst in March 2005, lasting for ∼\sim5 days with detection significance of 73σ\sigma (20-40 keV) and with the emission at << 200 keV. The ASM observations reveal that the soft X-ray lightcurve shows a similar outburst to that detected by INTEGRAL, however the peak of the soft X-ray lightcurve either lags, or is preceded by, the hard X-ray (>>20 keV) outburst by ∼\sim2 days. This resembles the behavior of X-ray novae like XN 1124-683, hence it further suggests a LMXB nature for IGR J17098-3628. While the quality of the ASM data prevents us from drawing any definite conclusions, these discoveries are important clues that, coupled with future observations, will help to resolve the as yet unknown nature of IGR J17098-3628.Comment: 15 pages, 7 figure, accepted in PAS

    Discussion on the Relevance of Old Low-lying Land Reclamation and Soil Liquefaction

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    Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchive
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