24,399 research outputs found
Leptonic emission from microquasar jets: from radio to very high-energy gamma-rays
Microquasars are sources of very high-energy gamma-rays and, very probably,
high-energy gamma-ray emitters. We propose a model for a jet that can allow to
give accurate observational predictions for jet emission at different energies
and provide with physical information of the object using multiwavelength data.Comment: 2 pages, 1 figure. Proceedings of the conference: "International
Astronomical Union Symposium No. 230: Populations of High Energy Sources in
Galaxies". Edited by Evert J.A. Meurs & Giuseppina Fabbian
Recommended from our members
Census Snapshot: Indiana
Using data from the U.S. Census Bureau, this report provides demographic and economic information about same-sex couples and same-sex couples raising children in Indiana. We compare same-sex "unmarried partners," which the Census Bureau defines as an unmarried couple who "shares living quarters and has a close personal relationship," to different-sex married couples in Indiana
Evidences of evanescent Bloch waves in Phononic Crystals
We show both experimentally and theoretically the evanescent behaviour of
modes in the Band Gap (BG) of finite Phononic Crystal (PC). Based on
experimental and numerical data we obtain the imaginary part of the wave vector
in good agreement with the complex band structures obtained by the Extended
Plane Wave Expansion (EPWE). The calculated and measured acoustic field of a
localized mode out of the point defect inside the PC presents also evanescent
behaviour. The correct understanding of evanescent modes is fundamental for
designing narrow filters and wave guides based on Phononic Crystals with
defects.Comment: 8 pages, 3 figure
Census Snapshot: Minnesota
Using data from the U.S. Census Bureau, this report provides demographic and economic information about same-sex couples and same-sex couples raising children in Minnesota. We compare same-sex "unmarried partners," which the Census Bureau defines as an unmarried couple who "shares living quarters and has a close personal relationship," to different-sex married couples in Minnesota
METing SUSY on the Z peak
Recently the ATLAS experiment announced a 3 excess at the Z-peak
consisting of 29 pairs of leptons together with two or more jets, GeV and GeV, to be compared with
expected lepton pairs in the Standard Model. No excess outside the Z-peak was
observed. By trying to explain this signal with SUSY we find that only
relatively light gluinos, TeV, together with a
heavy neutralino NLSP of GeV decaying
predominantly to Z-boson plus a light gravitino, such that nearly every gluino
produces at least one Z-boson in its decay chain, could reproduce the excess.
We construct an explicit general gauge mediation model able to reproduce the
observed signal overcoming all the experimental limits. Needless to say, more
sophisticated models could also reproduce the signal, however, any model would
have to exhibit the following features, light gluinos, or heavy particles with
a strong production cross-section, producing at least one Z-boson in its decay
chain. The implications of our findings for the Run II at LHC with the scaling
on the Z peak, as well as for the direct search of gluinos and other SUSY
particles, are pointed out.Comment: 24 pages, 17 figures, simulation improved, Checkmate analysis added,
new benchmark point included. Typos corrected, conclusions unchange
Census Snapshot: Ohio
Using data from the U.S. Census Bureau, this report provides demographic and economic information about same-sex couples and same-sex couples raising children in Ohio. We compare same-sex "unmarried partners," which the Census Bureau defines as an unmarried couple who "shares living quarters and has a close personal relationship," to different-sex married couples in Ohio
The abundance of Bullet-groups in LCDM
We estimate the expected distribution of displacements between the two
dominant dark matter (DM) peaks (DM-DM displacements) and between DM and
gaseous baryon peak (DM-gas displacements) in dark matter halos with masses
larger than Msun/h. We use as a benchmark the observation of SL2S
J08544-0121, which is the lowest mass system ( Msun/h)
observed so far featuring a bi-modal dark matter distribution with a dislocated
gas component. We find that % of the dark matter halos with
circular velocities in the range 300 km/s to 700 km/s (groups) show DM-DM
displacements equal or larger than kpc/h as observed in SL2S
J08544-0121. For dark matter halos with circular velocities larger than 700
km/s (clusters) this fraction rises to 70 10%. Using the same simulation
we estimate the DM-gas displacements and find that 0.1 to 1.0% of the groups
should present separations equal or larger than kpc/h corresponding
to our observational benchmark; for clusters this fraction rises to (7
3)%, consistent with previous studies of dark matter to baryon separations.
Considering both constraints on the DM-DM and DM-gas displacements we find that
the number density of groups similar to SL2S J08544-0121 is Mpc, three times larger than the estimated value for clusters.
These results open up the possibility for a new statistical test of LCDM by
looking for DM-gas displacements in low mass clusters and groups.Comment: 6 pages, 3 figures, accepted for publication in ApJ Letter
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