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Measurement of top quark polarization in top-antitop events from proton-proton collisions at √s = 7 TeV using the ATLAS detector

Physical Review Letters 111:23 (2013)

Authors:

G Aad, T Abajyan, B Abbott, J Abdallah, SA Khalek, O Abdinov, R Aben, B Abi, M Abolins, OS Abou-Zeid, H Abramowicz, H Abreu, Y Abulaiti, BS Acharya, L Adamczyk, DL Adams, TN Addy, J Adelman, S Adomeit, T Adye, S Aefsky, T Agatonovic-Jovin, JA Aguilar-Saavedra, M Agustoni, SP Ahlen, A Ahmad, M Ahsan, G Aielli, TPA Åkesson, G Akimoto, AV Akimov, MA Alam, J Albert, S Albrand, MJA Verzini, M Aleksa, IN Aleksandrov, F Alessandria, C Alexa, G Alexander, G Alexandre, T Alexopoulos, M Alhroob, M Aliev, G Alimonti, L Alio, J Alison, BMM Allbrooke, LJ Allison, PP Allport, SE Allwood-Spiers, J Almond, A Aloisio, R Alon, A Alonso, F Alonso, A Altheimer, BA Gonzalez, MG Alviggi, K Amako, YA Coutinho, C Amelung, VV Ammosov, SPA Dos Santos, A Amorim, S Amoroso, N Amram, C Anastopoulos, LS Ancu, N Andari, T Andeen, CF Anders, G Anders, KJ Anderson, A Andreazza, V Andrei, XS Anduaga, S Angelidakis, P Anger, A Angerami, F Anghinolfi, AV Anisenkov, N Anjos, A Annovi, A Antonaki, M Antonelli, A Antonov, J Antos, F Anulli, M Aoki, LA Bella, R Apolle, G Arabidze, I Aracena, Y Arai, ATH Arce, S Arfaoui, JF Arguin, S Argyropoulos, E Arik

Abstract:

This Letter presents measurements of the polarization of the top quark in top-antitop quark pair events, using 4:7 fb–1of proton-proton collision data recorded with the ATLAS detector at the Large Hadron Collider at √s = 7 TeV. Final states containing one or two isolated leptons (electrons or muons) and jets are considered. Two measurements of αℓP, the product of the leptonic spin-analyzing power and the top quark polarization, are performed assuming that the polarization is introduced by either a CP conserving or a maximally CP violating production process. The measurements obtained, αℓPCPC=–0.035 ± 0.014(stat) ± 0:037(syst) and αℓPCPV= 0.020 ± 0:016(stat)+0.013–0.017(syst), are in good agreement with the standard model prediction of negligible top quark polarization.
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Herschel observations and a model for IRAS 08572+3915: A candidate for the most luminous infrared galaxy in the local (z < 0.2) Universe

Monthly Notices of the Royal Astronomical Society: Letters 437:1 (2013)

Authors:

A Efstathiou, C Pearson, D Farrah, D Rigopoulou, J Gracía-Carpio, A Verma, HWW Spoon, J Afonso, J Bernard-Salas, DL Clements, A Cooray, D Cormier, M Etxaluze, J Fischer, E Gonźalez-Alfonso, P Hurley, V Lebouteiller, SJ Oliver, M Rowan-Robinson, E Sturm

Abstract:

We present Herschel photometry and spectroscopy, carried out as part of the Herschel ultraluminous infrared galaxy (ULIRG) survey, and a model for the infrared to submillimetre emission of the ULIRG IRAS 08572+3915. This source shows one of the deepest known silicate absorption features and no polycyclic aromatic hydrocarbon emission. The model suggests that this object is powered by an active galactic nucleus (AGN) with a fairly smooth torus viewed almost edge-on and a very young starburst. According to our model, the AGN contributes about 90 per cent of the total luminosity of 1.1 × 1013 L⊙, which is about a factor of 5 higher than previous estimates. The large correction of the luminosity is due to theanisotropy of the emission of the best-fitting torus. Similar corrections may be necessary for other local and high-z analogues. This correction implies that IRAS 08572+3915 at a redshift of 0.058 35 may be the nearest hyperluminous infrared galaxy and probably the most luminous infrared galaxy in the local (z < 0.2) Universe. IRAS 08572+3915 shows a low ratio of [C II] to IR luminosity (log L[C II]/LIR < -3.8) and a [OI]63 μm to [CII]158 μm line ratio of about 1 that supports the model presented in this Letter ©2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.
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Characterising Exoplanet Atmospheres with High-resolution Spectroscopy

The Messenger 154 (2013) 57-61

Authors:

J Birkby, R de Kok, M Brogi, H Schwarz, S Albrecht, E de Mooij, I Snellen

Searching for transits in the Wide Field Camera Transit Survey with difference-imaging light curves

Astronomy & Astrophysics EDP Sciences 560 (2013) a92

Authors:

J Zendejas Dominguez, J Koppenhoefer, RP Saglia, JL Birkby, ST Hodgkin, G Kovács, DJ Pinfield, B Sipőcz, D Barrado, R Bender, C del Burgo, M Cappetta, EL Martín, SV Nefs, A Riffeser, P Steele
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The mass-metallicity relation at z~1.4 revealed with Subaru/FMOS

(2013)

Authors:

Kiyoto Yabe, Kouji Ohta, Fumihide Iwamuro, Masayuki Akiyama, Naoyuki Tamura, Suraphong Yuma, Masahiko Kimura, Naruhisa Takato, Yuki Moritani, Masanao Sumiyoshi, Toshinori Maihara, John Silverman, Gavin Dalton, Ian Lewis, David Bonfield, Hanshin Lee, Emma Curtis-Lake, Edward Macaulay, Fraser Clarke
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