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Measurement of dijet angular distributions and search for quark compositeness in pp collisions at √s=7TeV

Physical Review Letters 106:20 (2011)

Authors:

V Khachatryan, AM Sirunyan, A Tumasyan, W Adam, T Bergauer, M Dragicevic, J Erö, C Fabjan, M Friedl, R Frühwirth, VM Ghete, J Hammer, S Hänsel, C Hartl, M Hoch, N Hörmann, J Hrubec, M Jeitler, G Kasieczka, W Kiesenhofer, M Krammer, D Liko, I Mikulec, M Pernicka, H Rohringer, R Schöfbeck, J Strauss, A Taurok, F Teischinger, P Wagner, W Waltenberger, G Walzel, E Widl, CE Wulz, V Mossolov, N Shumeiko, J Suarez Gonzalez, L Benucci, K Cerny, EA De Wolf, X Janssen, T Maes, L Mucibello, S Ochesanu, B Roland, R Rougny, M Selvaggi, H Van Haevermaet, P Van Mechelen, N Van Remortel, S Beauceron, F Blekman, S Blyweert, J D'hondt, O Devroede, R Gonzalez Suarez, A Kalogeropoulos, J Maes, M Maes, S Tavernier, W Van Doninck, P Van Mulders, GP Van Onsem, I Villella, O Charaf, B Clerbaux, G De Lentdecker, V Dero, APR Gay, GH Hammad, T Hreus, PE Marage, L Thomas, C Vander Velde, P Vanlaer, J Wickens, V Adler, S Costantini, M Grunewald, B Klein, A Marinov, J Mccartin, D Ryckbosch, F Thyssen, M Tytgat, L Vanelderen, P Verwilligen, S Walsh, N Zaganidis, S Basegmez, G Bruno, J Caudron, L Ceard, J De Favereau De Jeneret, C Delaere, P Demin, D Favart, A Giammanco, G Grégoire, J Hollar

Abstract:

Dijet angular distributions are measured over a wide range of dijet invariant masses in pp collisions at √s=7TeV, at the CERN LHC. The event sample, recorded with the CMS detector, corresponds to an integrated luminosity of 36pb-1. The data are found to be in good agreement with the predictions of perturbative QCD, and yield no evidence of quark compositeness. With a modified frequentist approach, a lower limit on the contact interaction scale for left-handed quarks of Λ+=5.6TeV (Λ -=6.7TeV) for destructive (constructive) interference is obtained at the 95% confidence level. © 2011 American Physical Society.
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Rapid variations of polarization in low-mass X-ray binaries

Sissa Medialab Srl (2011) 009

Authors:

David M Russell, Piergiorgio Casella, Rob Fender, Paolo Soleri, Magaretha PRETORIUS, Fraser Lewis, M van der Klis
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Search for production of heavy particles decaying to top quarks and invisible particles in pp collisions at √s = 1.96  TeV.

Phys Rev Lett 106:19 (2011) 191801

Authors:

T Aaltonen, B Álvarez González, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, G Apollinari, JA Appel, A Apresyan, T Arisawa, A Artikov, J Asaadi, W Ashmanskas, B Auerbach, A Aurisano, F Azfar, W Badgett, A Barbaro-Galtieri, VE Barnes, BA Barnett, P Barria, P Bartos, M Bauce, G Bauer, F Bedeschi, D Beecher, S Behari, G Bellettini, J Bellinger, D Benjamin, A Beretvas, A Bhatti, M Binkley, D Bisello, I Bizjak, KR Bland, B Blumenfeld, A Bocci, A Bodek, D Bortoletto, J Boudreau, A Boveia, B Brau, L Brigliadori, A Brisuda, C Bromberg, E Brucken, M Bucciantonio, J Budagov, HS Budd, S Budd, K Burkett, G Busetto, P Bussey, A Buzatu, 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, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, K Cho, D Chokheli, JP Chou, WH Chung, YS Chung, CI Ciobanu, MA Ciocci, A Clark, G Compostella, ME Convery, J Conway, M Corbo, M Cordelli, CA Cox, DJ Cox, F Crescioli, C Cuenca Almenar, J Cuevas, R Culbertson, D Dagenhart, N d'Ascenzo, M Datta, P de Barbaro, S De Cecco, G De Lorenzo, M Dell'Orso, C Deluca, L Demortier, J Deng, M Deninno, F Devoto, M d'Errico, A Di Canto, B Di Ruzza, JR Dittmann, M D'Onofrio, S Donati, P Dong, M Dorigo, T Dorigo, K Ebina, A Elagin, A Eppig, R Erbacher, D Errede, S Errede, N Ershaidat, R Eusebi, HC Fang, S Farrington, M Feindt, JP Fernandez, C Ferrazza, R Field, G Flanagan, R Forrest, MJ Frank, M Franklin, JC Freeman, Y Funakoshi, I Furic, M Gallinaro, J Galyardt, JE Garcia, AF Garfinkel, P Garosi, H Gerberich, E Gerchtein, S Giagu, V Giakoumopoulou, P Giannetti, K Gibson, CM Ginsburg, N Giokaris, P Giromini, M Giunta, G Giurgiu, V Glagolev, D Glenzinski, M Gold, D Goldin, N Goldschmidt, A Golossanov, G Gomez, G Gomez-Ceballos, M Goncharov, O González, I Gorelov, AT Goshaw, K Goulianos, S Grinstein, C Grosso-Pilcher, RC Group, J Guimaraes da Costa, Z Gunay-Unalan, C Haber, SR Hahn, E Halkiadakis, A Hamaguchi, JY Han, F Happacher, K Hara, D Hare, M Hare, RF Harr, K Hatakeyama, C Hays, M Heck, J Heinrich, M Herndon, S Hewamanage, D Hidas, A Hocker, W Hopkins, D Horn, S Hou, RE Hughes, M Hurwitz, U Husemann, N Hussain, M Hussein, J Huston, G Introzzi, M Iori, A Ivanov, E James, D Jang, B Jayatilaka, EJ Jeon, MK Jha, S Jindariani, W Johnson, M Jones, KK Joo, SY Jun, TR Junk, T Kamon, PE Karchin, Y Kato, W Ketchum, J Keung, V Khotilovich, B Kilminster, DH Kim, HS Kim, HW Kim, JE Kim, MJ Kim, SB Kim, SH Kim, YK Kim, N Kimura, M Kirby, S Klimenko, K Kondo, DJ Kong, J Konigsberg, AV Kotwal, M Kreps, J Kroll, D Krop, N Krumnack, M Kruse, V Krutelyov, T Kuhr, M Kurata, S Kwang, AT Laasanen, S Lami, S Lammel, M Lancaster, RL Lander, K Lannon, A Lath, G Latino, T LeCompte, E Lee, HS Lee, JS Lee, SW Lee, S Leo, S Leone, JD Lewis, A Limosani, C-J Lin, J Linacre, M Lindgren, E Lipeles, A Lister, DO Litvintsev, C Liu, Q Liu, T Liu, S Lockwitz, NS Lockyer, A Loginov, D Lucchesi, J Lueck, P Lujan, P Lukens, G Lungu, J Lys, R Lysak, R Madrak, K Maeshima, K Makhoul, P Maksimovic, S Malik, G Manca, A Manousakis-Katsikakis, F Margaroli, C Marino, M Martínez, R Martínez-Ballarín, P Mastrandrea, M Mathis, ME Mattson, P Mazzanti, KS McFarland, P McIntyre, R McNulty, A Mehta, P Mehtala, A Menzione, C Mesropian, T Miao, D Mietlicki, A Mitra, H Miyake, S Moed, N Moggi, MN Mondragon, CS Moon, R Moore, MJ Morello, J Morlock, P Movilla Fernandez, A Mukherjee, Th Muller, P Murat, M Mussini, J Nachtman, Y Nagai, J Naganoma, I Nakano, A Napier, J Nett, C Neu, MS Neubauer, J Nielsen, L Nodulman, O Norniella, E Nurse, L Oakes, SH Oh, YD Oh, I Oksuzian, T Okusawa, R Orava, L Ortolan, S Pagan Griso, C Pagliarone, E Palencia, V Papadimitriou, AA Paramonov, J Patrick, G Pauletta, M Paulini, C Paus, DE Pellett, A Penzo, TJ Phillips, G Piacentino, E Pianori, J Pilot, K Pitts, C Plager, L Pondrom, K Potamianos, O Poukhov, F Prokoshin, A Pronko, F Ptohos, E Pueschel, G Punzi, J Pursley, A Rahaman, V Ramakrishnan, N Ranjan, K Rao, I Redondo, P Renton, M Rescigno, F Rimondi, L Ristori, A Robson, T Rodrigo, T Rodriguez, E Rogers, S Rolli, R Roser, M Rossi, F Rubbo, F Ruffini, A Ruiz, J Russ, V Rusu, A Safonov, WK Sakumoto, Y Sakurai, L Santi, L Sartori, K Sato, V Saveliev, A Savoy-Navarro, P Schlabach, A Schmidt, EE Schmidt, MP Schmidt, M Schmitt, T Schwarz, L Scodellaro, A Scribano, F Scuri, A Sedov, S Seidel, Y Seiya, A Semenov, F Sforza, A Sfyrla, SZ Shalhout, T Shears, PF Shepard, M Shimojima, S Shiraishi, M Shochet, I Shreyber, A Simonenko, P Sinervo, A Sissakian, K Sliwa, JR Smith, FD Snider, A Soha, S Somalwar, V Sorin, P Squillacioti, M Stancari, M Stanitzki, R St Denis, B Stelzer, O Stelzer-Chilton, D Stentz, J Strologas, GL Strycker, Y Sudo, A Sukhanov, I Suslov, K Takemasa, Y Takeuchi, J Tang, M Tecchio, PK Teng, J Thom, J Thome, GA Thompson, E Thomson, P Ttito-Guzmán, S Tkaczyk, D Toback, S Tokar, K Tollefson, T Tomura, D Tonelli, S Torre, D Torretta, P Totaro, M Trovato, Y Tu, F Ukegawa, S Uozumi, A Varganov, F Vázquez, G Velev, C Vellidis, M Vidal, I Vila, R Vilar, J Vizán, M Vogel, G Volpi, P Wagner, RL Wagner, T Wakisaka, R Wallny, SM Wang, A Warburton, D Waters, M Weinberger, WC Wester, B Whitehouse, D Whiteson, AB Wicklund, E Wicklund, S Wilbur, F Wick, HH Williams, JS Wilson, P Wilson, BL Winer, P Wittich, S Wolbers, H Wolfe, T Wright, X Wu, Z Wu, K Yamamoto, J Yamaoka, T Yang, UK Yang, YC Yang, W-M Yao, GP Yeh, K Yi, J Yoh, K Yorita, T Yoshida, GB Yu, I Yu, SS Yu, JC Yun, A Zanetti, Y Zeng, S Zucchelli, CDF Collaboration

Abstract:

We present a search for a new particle T' decaying to top quark via T' → t + X, where X is an invisible particle. In a data sample with 4.8  fb(-1) of integrated luminosity collected by the CDF II detector at Fermilab in pp collisions with √s = 1.96  TeV, we search for pair production of T' in the lepton + jets channel, pp → tt + X + X → ℓνbqq'b + X + X. We interpret our results primarily in terms of a model where T' are exotic fourth generation quarks and X are dark matter particles. Current direct and indirect bounds on such exotic quarks restrict their masses to be between 300 and 600  GeV/c2, the dark matter particle mass being anywhere below m(T'). The data are consistent with standard model expectations, and we set 95% confidence level limits on the generic production of T'T' → tt + X + X. For the dark matter model we exclude T' at 95% confidence level up to m(T') = 360  GeV/c2 for m(X) ≤ 100  GeV/c2.
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Discovery of a multiply lensed submillimeter galaxy in early HerMES Herschel/SPIRE data

Astrophysical Journal Letters 732:2 PART II (2011)

Authors:

A Conley, A Cooray, JD Vieira, EAG Solares, S Kim, JE Aguirre, A Amblard, R Auld, AJ Baker, A Beelen, A Blain, R Blundell, J Bock, CM Bradford, C Bridge, D Brisbin, D Burgarella, JM Carpenter, P Chanial, E Chapin, N Christopher, DL Clements, P Cox, SG Djorgovski, CD Dowell, S Eales, L Earle, TP Ellsworth-Bowers, D Farrah, A Franceschini, D Frayer, H Fu, R Gavazzi, J Glenn, M Griffin, MA Gurwell, M Halpern, E Ibar, RJ Ivison, M Jarvis, J Kamenetzky, M Krips, L Levenson, R Lupu, A Mahabal, PD Maloney, C Maraston, L Marchetti, G Marsden, H Matsuhara, AMJ Mortier, E Murphy, BJ Naylor, R Neri, HT Nguyen, SJ Oliver, A Omont, MJ Page, A Papageorgiou, CP Pearson, I Pérez-Fournon, M Pohlen, N Rangwala, JI Rawlings, G Raymond, D Riechers, G Rodighiero, IG Roseboom, M Rowan-Robinson, B Schulz, D Scott, K Scott, P Serra, N Seymour, DL Shupe, AJ Smith, M Symeonidis, KE Tugwell, M Vaccari, E Valiante, I Valtchanov, A Verma, MP Viero, L Vigroux, L Wang, D Wiebe, G Wright, CK Xu, G Zeimann, M Zemcov, J Zmuidzinas

Abstract:

We report the discovery of a bright (f (250 μm)>400 mJy), multiply lensed submillimeter galaxy HERMES J105751.1+573027 in Herschel/SPIRE Science Demonstration Phase data from the HerMES project. Interferometric 880 μm Submillimeter Array observations resolve at least four images with a large separation of ∼9″. A high-resolution adaptive optics Kp image with Keck/NIRC2 clearly shows strong lensing arcs. Follow-up spectroscopy gives a redshift of z = 2.9575, and the lensing model gives a total magnification of μ ∼ 11 ± 1. The large image separation allows us to study the multi-wavelength spectral energy distribution (SED) of the lensed source unobscured by the central lensing mass. The far-IR/millimeter-wave SED is well described by a modified blackbody fit with an unusually warm dust temperature, 88 ± 3 K. We derive a lensing-corrected total IR luminosity of (1.43 ± 0.09) × 1013 L⊙, implying a star formation rate of ∼2500 M⊙ yr-1. However, models primarily developed from brighter galaxies selected at longer wavelengths are a poor fit to the full optical-to-millimeter SED. A number of other strongly lensed systems have already been discovered in early Herschel data, and many more are expected as additional data are collected. © 2011. The American Astronomical Society. All rights reserved.
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Measurements of direct CP violating asymmetries in charmless decays of strange bottom mesons and bottom baryons.

Phys Rev Lett 106:18 (2011) 181802

Authors:

T Aaltonen, B Alvarez González, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, G Apollinari, JA Appel, A Apresyan, T Arisawa, A Artikov, J Asaadi, W Ashmanskas, B Auerbach, A Aurisano, F Azfar, W Badgett, A Barbaro-Galtieri, VE Barnes, BA Barnett, P Barria, P Bartos, M Bauce, G Bauer, F Bedeschi, D Beecher, S Behari, G Bellettini, J Bellinger, D Benjamin, A Beretvas, A Bhatti, M Binkley, D Bisello, I Bizjak, KR Bland, B Blumenfeld, A Bocci, A Bodek, D Bortoletto, J Boudreau, A Boveia, B Brau, L Brigliadori, A Brisuda, C Bromberg, E Brucken, M Bucciantonio, J Budagov, HS Budd, S Budd, K Burkett, G Busetto, P Bussey, A Buzatu, 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, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, K Cho, D Chokheli, JP Chou, WH Chung, YS Chung, CI Ciobanu, MA Ciocci, A Clark, G Compostella, ME Convery, J Conway, M Corbo, M Cordelli, CA Cox, DJ Cox, F Crescioli, C Cuenca Almenar, J Cuevas, R Culbertson, D Dagenhart, N d'Ascenzo, M Datta, P de Barbaro, S De Cecco, G De Lorenzo, M Dell'orso, C Deluca, L Demortier, J Deng, M Deninno, F Devoto, M d'Errico, A Di Canto, B Di Ruzza, JR Dittmann, M D'Onofrio, S Donati, P Dong, M Dorigo, T Dorigo, K Ebina, A Elagin, A Eppig, R Erbacher, D Errede, S Errede, N Ershaidat, R Eusebi, HC Fang, S Farrington, M Feindt, JP Fernandez, C Ferrazza, R Field, G Flanagan, R Forrest, MJ Frank, M Franklin, JC Freeman, Y Funakoshi, I Furic, M Gallinaro, J Galyardt, JE Garcia, AF Garfinkel, P Garosi, H Gerberich, E Gerchtein, S Giagu, V Giakoumopoulou, P Giannetti, K Gibson, CM Ginsburg, N Giokaris, P Giromini, M Giunta, G Giurgiu, V Glagolev, D Glenzinski, M Gold, D Goldin, N Goldschmidt, A Golossanov, G Gomez, G Gomez-Ceballos, M Goncharov, O González, I Gorelov, AT Goshaw, K Goulianos, A Gresele, S Grinstein, C Grosso-Pilcher, RC Group, J Guimaraes da Costa, Z Gunay-Unalan, C Haber, SR Hahn, E Halkiadakis, A Hamaguchi, JY Han, F Happacher, K Hara, D Hare, M Hare, RF Harr, K Hatakeyama, C Hays, M Heck, J Heinrich, M Herndon, S Hewamanage, D Hidas, A Hocker, W Hopkins, D Horn, S Hou, RE Hughes, M Hurwitz, U Husemann, N Hussain, M Hussein, J Huston, G Introzzi, M Iori, A Ivanov, E James, D Jang, B Jayatilaka, EJ Jeon, MK Jha, S Jindariani, W Johnson, M Jones, KK Joo, SY Jun, TR Junk, T Kamon, PE Karchin, Y Kato, W Ketchum, J Keung, V Khotilovich, B Kilminster, DH Kim, HS Kim, HW Kim, JE Kim, MJ Kim, SB Kim, SH Kim, YK Kim, N Kimura, M Kirby, S Klimenko, K Kondo, DJ Kong, J Konigsberg, AV Kotwal, M Kreps, J Kroll, D Krop, N Krumnack, M Kruse, V Krutelyov, T Kuhr, M Kurata, S Kwang, AT Laasanen, S Lami, S Lammel, M Lancaster, RL Lander, K Lannon, A Lath, G Latino, I Lazzizzera, T Lecompte, E Lee, HS Lee, JS Lee, SW Lee, S Leo, S Leone, JD Lewis, C-J Lin, J Linacre, M Lindgren, E Lipeles, A Lister, DO Litvintsev, C Liu, Q Liu, T Liu, S Lockwitz, NS Lockyer, A Loginov, D Lucchesi, J Lueck, P Lujan, P Lukens, G Lungu, J Lys, R Lysak, R Madrak, K Maeshima, K Makhoul, P Maksimovic, S Malik, G Manca, A Manousakis-Katsikakis, F Margaroli, C Marino, M Martínez, R Martínez-Ballarín, P Mastrandrea, M Mathis, ME Mattson, P Mazzanti, KS McFarland, P McIntyre, R McNulty, A Mehta, P Mehtala, A Menzione, C Mesropian, T Miao, D Mietlicki, A Mitra, H Miyake, S Moed, N Moggi, MN Mondragon, CS Moon, R Moore, MJ Morello, J Morlock, P Movilla Fernandez, A Mukherjee, Th Muller, P Murat, M Mussini, J Nachtman, Y Nagai, J Naganoma, I Nakano, A Napier, J Nett, C Neu, MS Neubauer, J Nielsen, L Nodulman, O Norniella, E Nurse, L Oakes, SH Oh, YD Oh, I Oksuzian, T Okusawa, R Orava, L Ortolan, S Pagan Griso, C Pagliarone, E Palencia, V Papadimitriou, AA Paramonov, J Patrick, G Pauletta, M Paulini, C Paus, DE Pellett, A Penzo, TJ Phillips, G Piacentino, E Pianori, J Pilot, K Pitts, C Plager, L Pondrom, K Potamianos, O Poukhov, F Prokoshin, A Pronko, F Ptohos, E Pueschel, G Punzi, J Pursley, A Rahaman, V Ramakrishnan, N Ranjan, I Redondo, P Renton, M Rescigno, F Rimondi, L Ristori, A Robson, T Rodrigo, T Rodriguez, E Rogers, S Rolli, R Roser, M Rossi, F Rubbo, F Ruffini, A Ruiz, J Russ, V Rusu, A Safonov, WK Sakumoto, Y Sakurai, L Santi, L Sartori, K Sato, V Saveliev, A Savoy-Navarro, P Schlabach, A Schmidt, EE Schmidt, MP Schmidt, M Schmitt, T Schwarz, L Scodellaro, A Scribano, F Scuri, A Sedov, S Seidel, Y Seiya, A Semenov, F Sforza, A Sfyrla, SZ Shalhout, T Shears, PF Shepard, M Shimojima, S Shiraishi, M Shochet, I Shreyber, A Simonenko, P Sinervo, A Sissakian, K Sliwa, JR Smith, FD Snider, A Soha, S Somalwar, V Sorin, P Squillacioti, M Stancari, M Stanitzki, R St Denis, B Stelzer, O Stelzer-Chilton, D Stentz, J Strologas, GL Strycker, Y Sudo, A Sukhanov, I Suslov, K Takemasa, Y Takeuchi, J Tang, M Tecchio, PK Teng, J Thom, J Thome, GA Thompson, E Thomson, P Ttito-Guzmán, S Tkaczyk, D Toback, S Tokar, K Tollefson, T Tomura, D Tonelli, S Torre, D Torretta, P Totaro, M Trovato, Y Tu, F Ukegawa, S Uozumi, A Varganov, F Vázquez, G Velev, C Vellidis, M Vidal, I Vila, R Vilar, J Vizán, M Vogel, G Volpi, P Wagner, RL Wagner, T Wakisaka, R Wallny, SM Wang, A Warburton, D Waters, M Weinberger, WC Wester, B Whitehouse, D Whiteson, AB Wicklund, E Wicklund, S Wilbur, F Wick, HH Williams, JS Wilson, P Wilson, BL Winer, P Wittich, S Wolbers, H Wolfe, T Wright, X Wu, Z Wu, K Yamamoto, J Yamaoka, T Yang, UK Yang, YC Yang, W-M Yao, GP Yeh, K Yi, J Yoh, K Yorita, T Yoshida, GB Yu, I Yu, SS Yu, JC Yun, A Zanetti, Y Zeng, S Zucchelli, CDF Collaboration

Abstract:

We report measurements of direct CP-violating asymmetries in charmless decays of neutral bottom hadrons to pairs of charged hadrons with the upgraded Collider Detector at the Fermilab Tevatron. Using a data sample corresponding to 1 fb(-1) of integrated luminosity, we obtain the first measurements of direct CP violation in bottom strange mesons, A(CP)(B(s)(0)→K(-)π(+))=+0.39±0.15(stat)±0.08(syst), and bottom baryons, A(CP)(Λ(b)(0)→pπ(-))=+0.03±0.17(stat)±0.05(syst) and A(CP)(Λ(b)(0)→pK(-))=+0.37±0.17(stat)±0.03(syst). In addition, we measure CP violation in B(0)→K(+)π(-) decays with 3.5σ significance, A(CP)(B(0)→K(+)π(-))=-0.086±0.023(stat)±0.009(syst), in agreement with the current world average. Measurements of branching fractions of B(s)(0)→K(+)K(-) and B(0)→π(+)π(-) decays are also updated.
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