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‘Disc–Jet’ Coupling in Black Hole X-Ray Binaries and Active Galactic Nuclei

Chapter in The Jet Paradigm, Springer Nature 794 (2010) 115-142
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Higher-order multipole amplitudes in charmonium radiative transitions

Physical Review D - Particles, Fields, Gravitation and Cosmology 80:11 (2009)

Authors:

M Artuso, S Blusk, S Khalil, R Mountain, K Randrianarivony, T Skwarnicki, S Stone, JC Wang, LM Zhang, G Bonvicini, D Cinabro, A Lincoln, MJ Smith, P Zhou, J Zhu, P Naik, J Rademacker, DM Asner, KW Edwards, J Reed, AN Robichaud, G Tatishvili, EJ White, RA Briere, H Vogel, PUE Onyisi, JL Rosner, JP Alexander, DG Cassel, R Ehrlich, L Fields, RS Galik, L Gibbons, SW Gray, DL Hartill, BK Heltsley, JM Hunt, DL Kreinick, VE Kuznetsov, J Ledoux, H Mahlke-Krüger, JR Patterson, D Peterson, D Riley, A Ryd, AJ Sadoff, X Shi, S Stroiney, WM Sun, J Yelton, P Rubin, N Lowrey, S Mehrabyan, M Selen, J Wiss, M Kornicer, RE Mitchell, MR Shepherd, CM Tarbert, D Besson, TK Pedlar, J Xavier, D Cronin-Hennessy, KY Gao, J Hietala, R Poling, P Zweber, S Dobbs, Z Metreveli, KK Seth, BJY Tan, A Tomaradze, S Brisbane, J Libby, L Martin, A Powell, P Spradlin, C Thomas, G Wilkinson, H Mendez, JY Ge, DH Miller, IPJ Shipsey, B Xin, GS Adams, D Hu, B Moziak, J Napolitano, KM Ecklund, J Insler, H Muramatsu, CS Park, EH Thorndike, F Yang

Abstract:

Using 24×106 ψ′≡ψ(2S) decays in CLEO-c, we have searched for higher multipole admixtures in electric-dipole-dominated radiative transitions in charmonia. We find good agreement between our data and theoretical predictions for magnetic quadrupole (M2) amplitudes in the transitions ψ′→γχc1,c2 and χc1,c2→γJ/ ψ, in striking contrast to some previous measurements. Let b2J and a2J denote the normalized M2 amplitudes in the respective aforementioned decays, where the superscript J refers to the angular momentum of the χcJ. By performing unbinned maximum likelihood fits to full five-parameter angular distributions, we found the following values of M2 admixtures for Jχ=1: a2J=1=(-6.26±0.63±0.24)×10-2 and b2J=1=(2.76±0. 73±0.23)×10-2, which agree well with theoretical expectations for a vanishing anomalous magnetic moment of the charm quark. For Jχ=2, if we fix the electric octupole (E3) amplitudes to zero as theory predicts for transitions between charmonium S states and P states, we find a2J=2=(-9.3±1.6±0.3)×10-2 and b2J=2=(1.0±1. 3±0.3)×10-2. If we allow for E3 amplitudes we find, with a four-parameter fit, a2J=2=(-7.9±1.9±0.3)×10-2, b2J=2=(0.2±1.4±0.4)×10-2, a3J=2=(1.7±1.4±0.3) ×10-2, and b3J=2=(-0.8±1.2±0.2)×10-2. We determine the ratios a2J=1/a2J=2=0.67-0.13+0.19 and a2J=1/b2J=1=-2.27-0.99+0.57, where the theoretical predictions are independent of the charmed quark magnetic moment and are a2J=1/a2J=2=0.676±0.071 and a2J=1/b2J=1=-2.27±0.16. © 2009 The American Physical Society.
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Measurement of the pseudoscalar decay constant fDs using Ds+→τ+ν, τ+→ρ+ν̄ decays

Physical Review D - Particles, Fields, Gravitation and Cosmology 80:11 (2009)

Authors:

P Naik, J Rademacker, DM Asner, KW Edwards, K Randrianarivony, J Reed, AN Robichaud, G Tatishvili, EJ White, RA Briere, H Vogel, PUE Onyisi, JL Rosner, JP Alexander, DG Cassel, R Ehrlich, L Fields, L Gibbons, SW Gray, DL Hartill, BK Heltsley, JM Hunt, DL Kreinick, VE Kuznetsov, J Ledoux, JR Patterson, D Peterson, D Riley, A Ryd, AJ Sadoff, X Shi, S Stroiney, WM Sun, J Yelton, P Rubin, N Lowrey, S Mehrabyan, M Selen, J Wiss, M Kornicer, RE Mitchell, MR Shepherd, CM Tarbert, D Besson, TK Pedlar, J Xavier, D Cronin-Hennessy, KY Gao, J Hietala, R Poling, P Zweber, S Dobbs, Z Metreveli, KK Seth, BJY Tan, A Tomaradze, S Brisbane, J Libby, L Martin, A Powell, P Spradlin, G Wilkinson, H Mendez, JY Ge, DH Miller, IPJ Shipsey, B Xin, GS Adams, D Hu, B Moziak, J Napolitano, KM Ecklund, J Insler, H Muramatsu, CS Park, EH Thorndike, F Yang, S Ricciardi, C Thomas, M Artuso, S Blusk, S Khalil, R Mountain, T Skwarnicki, S Stone, JC Wang, LM Zhang, G Bonvicini, D Cinabro, A Lincoln, MJ Smith, P Zhou, J Zhu

Abstract:

Analyzing 600pb-1 of e+e- collisions at 4170 MeV center-of-mass energy with the CLEO-c detector, we measure the branching fraction B(Ds+→τ+ν)= (5.52±0.57±0.21)% using the τ+→ρ+ν̄ decay mode. Combining with other CLEO measurements of B(Ds+→τ+ν) we determine the pseudoscalar decay constant fDs=(259.7±7.8±3.4)MeV consistent with the value obtained from our Ds+→μ+ν measurement of (257.6±10.3±4.3)MeV. Combining these measurements we find a value of fDs=(259.0±6.2±3.0)MeV, that differs from the most accurate prediction based on unquenched lattice gauge theory of (241±3)MeV by 2.4 standard deviations. We also present the first measurements of B(Ds+→K0π+π0)=(1.00±0.18±0.04)%, and B(Ds+→π+π0π0)=(0.65±0.13±0.03)%, and measure a new value for B(Ds+→ηρ+)=(8.9±0.6±0.5)%. © 2009 The American Physical Society.
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Measurement of the inclusive isolated prompt photon cross section in pp̄ collisions at s=1.96TeV using the CDF detector

Physical Review D - Particles, Fields, Gravitation and Cosmology 80:11 (2009)

Authors:

T Aaltonen, J Adelman, BA González, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, G Apollinari, A Apresyan, T Arisawa, A Artikov, J Asaadi, W Ashmanskas, A Attal, A Aurisano, F Azfar, W Badgett, A Barbaro-Galtieri, VE Barnes, BA Barnett, P Barria, P Bartos, G Bauer, PH Beauchemin, F Bedeschi, D Beecher, S Behari, G Bellettini, J Bellinger, D Benjamin, A Beretvas, A Bhatti, M Binkley, D Bisello, I Bizjak, RE Blair, C Blocker, B Blumenfeld, A Bocci, A Bodek, V Boisvert, D Bortoletto, J Boudreau, A Boveia, B Brau, A Bridgeman, L Brigliadori, C Bromberg, E Brubaker, J Budagov, HS Budd, S Budd, K Burkett, G Busetto, P Bussey, A Buzatu, KL Byrum, S Cabrera, C Calancha, S Camarda, M Campanelli, M Campbell, F Canelli, A Canepa, B Carls, D Carlsmith, R Carosi, S Carrillo, S Carron, B Casal, M Casarsa, A Castro, P Catastini, D Cauz, V Cavaliere, M Cavalli-Sforza, A Cerri, L Cerrito, SH Chang, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, K Cho, D Chokheli, JP Chou, G Choudalakis, K Chung, WH Chung, YS Chung, T Chwalek, CI Ciobanu, MA Ciocci, A Clark, D Clark, G Compostella, ME Convery, J Conway

Abstract:

A measurement of the cross section for the inclusive production of isolated photons by the CDF experiment at the Fermilab Tevatron collider is presented. The measurement covers the pseudorapidity region |ηγ|<1.0 and the transverse energy range ETγ>30GeV and is based on 2.5fb-1 of integrated luminosity. The sample is almost a factor of 7 larger than those used for recent published results and extends the ETγ coverage by 100 GeV. The result agrees with next-to-leading order perturbative QCD calculations within uncertainties over the range 50
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The gemini/HST cluster project: Structural and photometric properties of galaxies in three z = 0.28-0.89 clusters

Astrophysical Journal, Supplement Series 184:2 (2009) 271-287

Authors:

K Chiboucas, J Barr, K Flint, I Jørgensen, M Collobert, R Davies

Abstract:

We present the data processing and analysis techniques we are using to determine the structural and photometric properties of galaxies in our Gemini/HST Galaxy Cluster Project sample. The goal of this study is to understand cluster galaxy evolution in terms of scaling relations and structural properties of cluster galaxies at redshifts 0.15 < z < 1.0. To derive parameters such as total magnitude, half-light radius, effective surface brightness, and Sersic n, we fit r 1/4 law and Sersic function two-dimensional surface brightness profiles to each of the galaxies in our sample. Using simulated galaxies, we test how the assumed profile affects the derived parameters and how the uncertainties affect our Fundamental Plane results. We find that while fitting galaxies that have Sersic index n < 4 with r 1/4 law profiles systematically overestimates the galaxy radius and flux, the combination of profile parameters that enter the Fundamental Plane has uncertainties that are small. Average systematic offsets and associated random uncertainties in magnitude and log re for n>2 galaxies fitted with r 1/4 law profiles are -0.1±0.3 and 0.1±0.2, respectively. The combination of effective radius and surface brightness, log re - βlog 〈I〉e, that enters the Fundamental Plane produces offsets smaller than -0.02±0.10. This systematic error is insignificant and independent of galaxy magnitude or size. A catalog of photometry and surface brightness profile parameters is presented for three of the clusters in our sample, RX J0142.0+2131, RX J0152.7-1357, and RX J1226.9+3332 at redshifts 0.28, 0.83, and 0.89, respectively. © 2009. The American Astronomical Society. All rights reserved.
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