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Measurement of the prompt J/ψ and ψ(2S) polarizations in pp collisions at s=7 TeV

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 727:4-5 (2013) 381-402

Authors:

S Chatrchyan, V Khachatryan, AM Sirunyan, A Tumasyan, W Adam, T Bergauer, M Dragicevic, J Erö, C Fabjan, M Friedl, R Frühwirth, VM Ghete, N Hörmann, J Hrubec, M Jeitler, W Kiesenhofer, V Knünz, M Krammer, I Krätschmer, D Liko, I Mikulec, D Rabady, B Rahbaran, C Rohringer, H Rohringer, R Schöfbeck, J Strauss, A Taurok, W Treberer-Treberspurg, W Waltenberger, CE Wulz, V Mossolov, N Shumeiko, J Suarez Gonzalez, S Alderweireldt, M Bansal, S Bansal, T Cornelis, EA De Wolf, X Janssen, A Knutsson, S Luyckx, L Mucibello, S Ochesanu, B Roland, R Rougny, Z Staykova, H Van Haevermaet, P Van Mechelen, N Van Remortel, A Van Spilbeeck, F Blekman, S Blyweert, J D'Hondt, A Kalogeropoulos, J Keaveney, M Maes, A Olbrechts, S Tavernier, W Van Doninck, P Van Mulders, GP Van Onsem, I Villella, C Caillol, B Clerbaux, G De Lentdecker, L Favart, APR Gay, T Hreus, A Léonard, PE Marage, A Mohammadi, L Perniè, T Reis, T Seva, L Thomas, C Vander Velde, P Vanlaer, J Wang, V Adler, K Beernaert, L Benucci, A Cimmino, S Costantini, S Dildick, G Garcia, B Klein, J Lellouch, A Marinov, J Mccartin, AA Ocampo Rios, D Ryckbosch, M Sigamani, N Strobbe, F Thyssen, M Tytgat, S Walsh, E Yazgan, N Zaganidis, S Basegmez

Abstract:

The polarizations of prompt J/ψ and ψ(2S) mesons are measured in proton-proton collisions at s=7 TeV, using a dimuon data sample collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 4.9 fb-1. The prompt J/ψ and ψ(2S) polarization parameters λθ{symbol}, λφ, and λθ{symbol}φ, as well as the frame-invariant quantity λ~, are measured from the dimuon decay angular distributions in three different polarization frames. The J/ψ results are obtained in the transverse momentum range 14

Black hole spin measurements through the relativistic precession model: XTE J1550-564

(2013)

Authors:

SE Motta, T Muñoz-Darias, A Sanna, R Fender, T Belloni, L Stella

DETECTION OF AN OUTBURST ONE YEAR PRIOR TO THE EXPLOSION OF SN 2011ht

The Astrophysical Journal Letters American Astronomical Society 779:1 (2013) l8

Authors:

M Fraser, M Magee, R Kotak, SJ Smartt, KW Smith, J Polshaw, AJ Drake, T Boles, C-H Lee, WS Burgett, KC Chambers, PW Draper, H Flewelling, KW Hodapp, N Kaiser, R-P Kudritzki, EA Magnier, PA Price, JL Tonry, RJ Wainscoat, C Waters

Discovery of a new kind of explosive X-ray transient near M86

Astrophysical Journal 779:1 (2013)

Authors:

PG Jonker, A Glennie, M Heida, T Maccarone, S Hodgkin, G Nelemans, JCA Miller-Jones, MAP Torres, R Fender

Abstract:

We present the discovery of a new type of explosive X-ray flash in Chandra images of the old elliptical galaxy M86. This unique event is characterized by the peak luminosity of 6 × 1042 erg s-1 for the distance of M86, the presence of precursor events, the timescale between the precursors and the main event (∼4000 s), the absence of detectable hard X-ray and γ-ray emission, the total duration of the event, and the detection of a faint associated optical signal. The transient is located close to M86 in the Virgo cluster at the location where gas and stars are seen protruding from the galaxy probably due to an ongoing wet minor merger. We discuss the possible mechanisms for the transient and conclude that the X-ray flash could have been caused by the disruption of a compact white dwarf star by a ∼104 M black hole. Alternative scenarios such that of a foreground neutron star accreting an asteroid or the detection of an off-axis (short) γ-ray burst cannot be excluded at present. © 2013. The American Astronomical Society. All rights reserved..

Gravitational lens models based on Submillimeter Array Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.-selected strongly lensed sub-millimeter galaxies at z > 1.5

Astrophysical Journal 779:1 (2013)

Authors:

RS Bussmann, I Pérez-Fournon, S Amber, J Calanog, MA Gurwell, H Dannerbauer, F De Bernardis, H Fu, AI Harris, M Krips, A Lapi, R Maiolino, A Omont, D Riechers, J Wardlow, AJ Baker, M Birkinshaw, J Bock, N Bourne, DL Clements, A Cooray, G De Zotti, L Dunne, S Dye, S Eales, D Farrah, R Gavazzi, J González Nuevo, R Hopwood, E Ibar, RJ Ivison, N Laporte, S Maddox, P Martínez-Navajas, M Michalowski, M Negrello, SJ Oliver, IG Roseboom, D Scott, S Serjeant, AJ Smith, M Smith, A Streblyanska, E Valiante, P Van Der Werf, A Verma, JD Vieira, L Wang, D Wilner

Abstract:

Strong gravitational lenses are now being routinely discovered in wide-field surveys at (sub-)millimeter wavelengths. We present Submillimeter Array (SMA) high-spatial resolution imaging and Gemini-South and Multiple Mirror Telescope optical spectroscopy of strong lens candidates discovered in the two widest extragalactic surveys conducted by the Herschel Space Observatory: the Herschel-Astrophysical Terahertz Large Area Survey (H-ATLAS) and the Herschel Multi-tiered Extragalactic Survey (HerMES). From a sample of 30 Herschel sources with S 500 > 100 mJy, 21 are strongly lensed (i.e., multiply imaged), 4 are moderately lensed (i.e., singly imaged), and the remainder require additional data to determine their lensing status. We apply a visibility-plane lens modeling technique to the SMA data to recover information about the masses of the lenses as well as the intrinsic (i.e., unlensed) sizes (r half) and far-infrared luminosities (L FIR) of the lensed submillimeter galaxies (SMGs). The sample of lenses comprises primarily isolated massive galaxies, but includes some groups and clusters as well. Several of the lenses are located at z lens > 0.7, a redshift regime that is inaccessible to lens searches based on Sloan Digital Sky Survey spectroscopy. The lensed SMGs are amplified by factors that are significantly below statistical model predictions given the 500 μm flux densities of our sample. We speculate that this may reflect a deficiency in our understanding of the intrinsic sizes and luminosities of the brightest SMGs. The lensed SMGs span nearly one decade in L FIR (median L FIR = 7.9 × 10 12 L ) and two decades in FIR luminosity surface density (median ΣFIR = 6.0 × 1011 L kpc-2). The strong lenses in this sample and others identified via (sub-)mm surveys will provide a wealth of information regarding the astrophysics of galaxy formation and evolution over a wide range in redshift. © 2013. The American Astronomical Society. All rights reserved..