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2015-01-19
08:12
Search for pair-produced long-lived neutral particles decaying in the ATLAS hadronic calorimeter in $pp$ collisions at $\sqrt{s}$ = 8 TeV / ATLAS Collaboration
The ATLAS detector at the Large Hadron Collider at CERN is used to search for the decay of a scalar boson to a pair of long-lived particles, neutral under the Standard Model gauge group, in 20.3 fb$^{-1}$ of data collected in proton--proton collisions at $\sqrt{s}$ = 8 TeV. This search is sensitive to long-lived particles that decay to Standard Model particles producing jets at the outer edge of the ATLAS electromagnetic calorimeter or inside the hadronic calorimeter. [...]
arXiv:1501.04020; CERN-PH-EP-2014-228.- 2015 - 10 p. - Published in : Phys. Lett. B 743 (2015) 15-34 Elsevier Open Access article : PDF; Fulltext: PDF; External link: Preprint

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2014-12-04
15:27
Measurement of the transverse polarization of $\Lambda$ and $\bar{\Lambda}$ hyperons produced in proton--proton collisions at $\sqrt{s}$=7 TeV using the ATLAS detector / ATLAS Collaboration
The transverse polarization of $\Lambda$ and $\bar\Lambda$ hyperons produced in proton--proton collisions at a center-of-mass energy of 7 TeV is measured. The analysis uses 760 $\mu$b$^{-1}$ of minimum bias data collected by the ATLAS detector at the LHC in the year 2010. [...]
arXiv:1412.1692; CERN-PH-EP-2014-258.- Geneva : CERN, 2015 - 10 p. - Published in : Phys. Rev. D 91 (2015) 032004 Fulltext: PDF; External links: Previous draft version; Preprint

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2014-11-27
08:06
Measurement of the lifetime of the $B_c^+$ meson using the $B_c^+ \rightarrow J/\psi\pi^+$ decay mode / LHCb collaboration
The difference in total widths between the $B_c^+$ and $B^+$ mesons is measured using 3.0fb$^{-1}$ of data collected by the LHCb experiment in 7 and 8 TeV centre-of-mass energy proton-proton collisions at the LHC. Through the study of the time evolution of $B_c^+ \rightarrow J/\psi \pi^+$ and $B^+\rightarrow J/\psi K^+$ decays, the width difference is measured to be $ \Delta\Gamma \equiv \Gamma_{B_c^+} - \Gamma_{B^+} = 4.46 \pm 0.14 \pm 0.07mm^{-1}c,$ where the first uncertainty is statistical and the second systematic. [...]
arXiv:1411.6899; CERN-PH-EP-2014-283; LHCB-PAPER-2014-060.- Geneva : CERN, 2015 - 19 p. - Published in : Phys. Lett. B 742 (2015) 29-37 Elsevier Open Access article : PDF; Fulltext: PDF; Related data file(s): ZIP; External link: Preprint

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2014-11-25
10:28
Search for long-lived neutral particles decaying to quark-antiquark pairs in proton-proton collisions at $\sqrt{s}$ = 8 TeV / CMS Collaboration
A search is performed for long-lived massive neutral particles decaying to quark-antiquark pairs. The experimental signature is a distinctive topology of a pair of jets, originating at a secondary vertex. [...]
arXiv:1411.6530; CMS-EXO-12-038; CERN-PH-EP-2014-256.- Geneva : CERN, 2015 - 35 p. - Published in : Phys. Rev. D 91 (2015) 012007 Fulltext: PDF; External link: Preprint

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2014-11-24
17:23
Searches for heavy long-lived charged particles with the ATLAS detector in proton--proton collisions at $\sqrt{s}$ = 8 TeV / ATLAS Collaboration
Searches for heavy long-lived charged particles are performed using a data sample of 19.8 fb$^{-1}$ from proton--proton collisions at a centre-of-mass energy of $\sqrt{s}$ = 8 TeV collected by the ATLAS detector at the Large Hadron Collider. No excess is observed above the estimated background and limits are placed on the mass of long-lived particles in various supersymmetric models. [...]
arXiv:1411.6795; CERN-PH-EP-2014-252.- Geneva : CERN, 2015 - 37 p. - Published in : J. High Energy Phys. 01 (2015) 068 Fulltext: PDF; Springer Open Access article: PDF; External links: Previous draft version; Preprint

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2014-11-21
22:07
Search for disappearing tracks in proton-proton collisions at $\sqrt{s}$ = 8 TeV / CMS Collaboration
A search is presented for long-lived charged particles that decay within the CMS detector and produce the signature of a disappearing track. Disappearing tracks are identified as those with little or no associated calorimeter energy deposits and with missing hits in the outer layers of the tracker. [...]
arXiv:1411.6006; CMS-EXO-12-034; CERN-PH-EP-2014-273.- Geneva : CERN, 2015 - 37 p. - Published in : J. High Energy Phys. 01 (2015) 096 Fulltext: PDF; Springer Open Access article: PDF; External link: Preprint

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2014-11-19
09:27
Observation of two new $\Xi_b^-$ baryon resonances / LHCb collaboration
Two structures are observed close to the kinematic threshold in the $\Xi_b^0\pi^-$ mass spectrum in a sample of proton-proton collision data, corresponding to an integrated luminosity of 3.0 fb$^{-1}$ recorded by the LHCb experiment. In the quark model, two baryonic resonances with quark content $bds$ are expected in this mass region: the spin-parity $J^P = \frac{1}{2}^+$ and $J^P=\frac{3}{2}^+$ states, denoted $\Xi_b^{\prime -}$ and $\Xi_b^{*-}$. [...]
arXiv:1411.4849; CERN-PH-EP-2014-279; LHCB-PAPER-2014-061.- Geneva : CERN, 2015 - 17 p. - Published in : Phys. Rev. Lett. 114 (2015) 062004 APS Open Access article: PDF; Fulltext: PDF; Related data file(s): ZIP; Related supplementary data file(s): ZIP; External link: Preprint

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2014-11-13
07:50
Precision measurement of $CP$ violation in $B_s^0 \to J/\psi K^+K^-$ decays / LHCb Collaboration
The time-dependent $CP$ asymmetry in $B_s^0 \to J/\psi K^+K^-$ decays is measured using $pp$ collision data, corresponding to an integrated luminosity of $3.0$fb$^{-1}$, collected with the LHCb detector at centre-of-mass energies of $7$ and $8$TeV. In a sample of 96 000 $B_s^0 \to J/\psi K^+K^-$ decays, the $CP$-violating phase $\phi_s$ is measured, as well as the decay widths $\Gamma_{L}$ and $\Gamma_{H}$ of the light and heavy mass eigenstates of the $B_s^0-\bar{B}_s^0$ system. [...]
arXiv:1411.3104; LHCB-PAPER-2014-059; CERN-PH-EP-2014-271.- Geneva : CERN, 2015 - 19 p. - Published in : Phys. Rev. Lett. 114 (2015) 041801 Fulltext: PDF; Related data file(s): ZIP; Related supplementary data file(s): ZIP; External link: Preprint

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2014-11-09
16:32
Measurements of the Nuclear Modification Factor for Jets in Pb+Pb Collisions at $\sqrt{s_{\mathrm{NN}}}=2.76$ TeV with the ATLAS Detector / ATLAS Collaboration
Measurements of inclusive jet production are performed in $pp$ and Pb+Pb collisions at $\sqrt{s_{\mathrm{NN}}}=2.76$ TeV with the ATLAS detector at the LHC, corresponding to integrated luminosities of 4.0 $\mathrm{pb}^{-1}$ and 0.14 $\mathrm{nb}^{-1}$ , respectively. The jets are identified with the anti-$k_t$ algorithm with $R=0.4$, and the spectra are measured over the kinematic range of jet transverse momentum $32 < p_{\mathrm{T}} < 500$ GeV, and absolute rapidity $|y| < 2.1$ and as a function of collision centrality. [...]
arXiv:1411.2357; CERN-PH-EP-2014-172.- Geneva : CERN, 2015 - 6 p. - Published in : Phys. Rev. Lett. 114 (2015) 072302 Fulltext: PDF; External links: Previous draft version; Preprint

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2014-11-06
08:30
Measurement of the Z+b-jet cross-section in pp collisions at $\sqrt{s}=7{\mathrm{\,Te\kern -0.1em V}}$ in the forward region / LHCb collaboration
The associated production of a Z boson or an off-shell photon $\gamma^*$ with a bottom quark in the forward region is studied using proton-proton collisions at a centre-of-mass energy of $7{\mathrm{\,Te\kern -0.1em V}}$. The Z bosons are reconstructed in the ${\text{Z}/\gamma^*}\rightarrow{\mu^{+}\mu^{-}}$ final state from muons with a transverse momentum larger than $20{\mathrm{\,Ge\kern -0.1em V}}$, while two transverse momentum thresholds are considered for jets ($10{\mathrm{\,Ge\kern -0.1em V}}$ and $20{\mathrm{\,Ge\kern -0.1em V}}$). [...]
arXiv:1411.1264; LHCB-PAPER-2014-055; CERN-PH-EP-2014-267.- Geneva : CERN, 2015 - 17 p. - Published in : J. High Energy Phys. 01 (2015) 064 Fulltext: PDF; Related data file(s): ZIP; Springer Open Access article: PDF; External link: Preprint

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