IFAE

About: IFAE is a other organization based out in Barcelona, Spain. It is known for research contribution in the topics: Large Hadron Collider & Galaxy. The organization has 664 authors who have published 1270 publications receiving 51097 citations. The organization is also known as: Instituto de Fisica de Altas Energias & IFAE.

Search for strong gravity in multijet final states produced in pp collisions at √s=13 TeV using the ATLAS detector at the LHC

Abstract: A search is conducted for new physics in multijet final states using 3.6 inverse femtobarns of data from proton-proton collisions at root s = 13TeV taken at the CERN Large Hadron Collider with the ...

Search for a Structure in the B-s(0) pi(+/-) Invariant Mass Spectrum with the ATLAS Experiment

Abstract: A search for the narrow structure, X(5568), reported by the D0 Collaboration in the decay sequence X→B_{s}^{0}π^{±}, B_{s}^{0}→J/ψϕ, is presented The analysis is based on a data sample recorded with the ATLAS detector at the LHC corresponding to 49 fb^{-1} of pp collisions at 7 TeV and 195 fb^{-1} at 8 TeV No significant signal was found Upper limits on the number of signal events, with properties corresponding to those reported by D0, and on the X production rate relative to B_{s}^{0} mesons, ρ_{X}, were determined at 95% confidence level The results are N(X)<382 and ρ_{X}<0015 for B_{s}^{0} mesons with transverse momenta above 10 GeV, and N(X)<356 and ρ_{X}<0016 for transverse momenta above 15 GeV Limits are also set for potential B_{s}^{0}π^{±} resonances in the mass range 5550 to 5700 MeV

Discovery of VHE γ-ray emission from the BL Lacertae object B3 2247+381 with the MAGIC telescopes

Abstract: Aims. We study the non-thermal jet emission of the BL Lac object B3 2247+381 during a high optical state. Methods. The MAGIC telescopes observed the source during 13 nights between September 30th and October 30th 2010, collecting a total of 14.2 hours of good quality very high energy (VHE) -ray data. Simultaneous multiwavelength data was obtained with X-ray observations by the Swift satellite and optical R-band observations at the KVA-telescope. We also use high energy -ray (HE, 0.1 GeV‐100 GeV) data from the Fermi satellite. Results. The BL Lac object B3 2247+381 (z=0.119) was detected, for the first time, at VHE -rays at a statistical significance of 5.6 �. A soft VHE spectrum with a photon index of -3.2± 0.6 was determined. No significant short term flux variations were found. We model the spectral energy distribution using a one-zone SSC-model, which can successfully describe our data.

Measurement of the cross-section and charge asymmetry of W bosons produced in proton–proton collisions at s√=8 TeV with the ATLAS detector

Abstract: This paper presents measurements of the $W^+ \rightarrow \mu ^+ u $ and $W^- \rightarrow \mu ^- u $ cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton–proton collisions at a centre-of-mass energy of 8 $\text {TeV}$ with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of $20.2~\text{ fb }^{-1}$ . The precision of the cross-section measurements varies between 0.8 and 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.

The Dark Energy Survey view of the Sagittarius stream : discovery of two faint stellar system candidates

Abstract: We report the discovery of two new candidate stellar systems in the constellation of Cetus using the data from the first two years of the Dark Energy Survey (DES). The objects, DES J0111-1341 and DES J0225+0304, are located at a heliocentric distance of ~25 kpc and appear to have old and metal-poor populations. Their distances to the Sagittarius orbital plane, ~1.73 kpc (DES J0111-1341) and ~0.50 kpc (DES J0225+0304), indicate that they are possibly associated with the Sagittarius dwarf stream. The half-light radius (rh ≃ 4.55 pc) and luminosity (MV ≃ +0.3) of DES J0111-1341 are consistent with it being an ultrafaint stellar cluster, while the half-light radius (rh ≃ 18.55 pc) and luminosity (MV ≃ -1.1) of DES J0225+0304 place it in an ambiguous region of size-luminosity space between stellar clusters and dwarf galaxies. Determinations of the characteristic parameters of the Sagittarius stream, metallicity spread (-2.18 ≲ [Fe/H] ≲ -0.95) and distance gradient (23 kpc ≲ D⊙ ≲ 29 kpc), within the DES footprint in the Southern hemisphere, using the same DES data, also indicate a possible association between these systems. If these objects are confirmed through spectroscopic follow-up to be gravitationally bound systems and to share a Galactic trajectory with the Sagittarius stream, DES J0111-1341 and DES J0225+0304 would be the first ultrafaint stellar systems associated with the Sagittarius stream. Furthermore, DES J0225+0304 would also be the first confirmed case of an ultrafaint satellite of a satellite.