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91.
We have developed a new type of all-fiber band-rejection filter consisting of a helicoidal long-period fiber grating pair of opposite helicities, which provides highly flexible spectral control over the rejection bandwidth. The detailed fabrication method and operation principles of the proposed bandwidth-tunable band-rejection filter are described. The proposed device enables unique rejection bandwidth tuning over more than 14 nm at the rejection level of 15 dB, with low insertion loss and polarization-dependent loss achieved by adjusting torsion stress. 相似文献
92.
Vaman C Andreoiu C Bazin D Becerril A Brown BA Campbell CM Chester A Cook JM Dinca DC Gade A Galaviz D Glasmacher T Hjorth-Jensen M Horoi M Miller D Moeller V Mueller WF Schiller A Starosta K Stolz A Terry JR Volya A Zelevinsky V Zwahlen H 《Physical review letters》2007,99(16):162501
Rare isotope beams of neutron-deficient 106,108,110Sn from the fragmentation of 124Xe were employed in an intermediate-energy Coulomb excitation experiment. The measured B(E2,0(1)(+)-->2(1)(+)) values for 108Sn and 110Sn and the results obtained for the 106Sn show that the transition strengths for these nuclei are larger than predicted by current state-of-the-art shell-model calculations. This discrepancy might be explained by contributions of the protons from within the Z = 50 shell to the structure of low-energy excited states in this region. 相似文献
93.
Cowan ML Anache-Ménier D Hildebrand WK Page JH van Tiggelen BA 《Physical review letters》2007,99(9):094301
Temporal fluctuations in the phase of waves transmitted through a dynamic, strongly scattering, mesoscopic sample are investigated using ultrasonic waves, and compared with theoretical predictions based on circular Gaussian statistics. The fundamental role of phase in diffusing acoustic wave spectroscopy is revealed, and phase statistics are also shown to provide a sensitive and accurate way to probe scatterer motions at both short and long time scales. 相似文献
94.
Acosta D Affolder T Ahn MH Akimoto T Albrow MG Ambrose D Amidei D Anastassov A Anikeev K Annovi A Antos J Aoki M Apollinari G Arguin JF Arisawa T Artikov A Asakawa T Ashmanskas W Attal A Azfar F Azzi-Bacchetta P Bacchetta N Bachacou H Badgett W Bailey S Barbaro-Galtieri A Barker G Barnes VE Barnett BA Baroiant S Barone M Bauer G Bedeschi F Behari S Belforte S Bell WH Bellettini G Bellinger J Benjamin D Beretvas A Bhatti A Binkley M Bisello D Bishai M Blair RE Blocker C Bloom K Blumenfeld B 《Physical review letters》2003,91(24):241804
We report on measurements of differential cross sections dsigma/dp(T) for prompt charm meson production in ppmacr; collisions at sqrt[s]=1.96 TeV using 5.8+/-0.3 pb(-1) of data from the CDF II detector at the Fermilab Tevatron. The data are collected with a new trigger that is sensitive to the long lifetime of hadrons containing heavy flavor. The charm meson cross sections are measured in the central rapidity region |y|=1 in four fully reconstructed decay modes: D0-->K-pi(+), D(*+)-->D0pi(+), D+-->K-pi(+)pi(+), D(+)(s)-->phipi(+), and their charge conjugates. The measured cross sections are compared to theoretical calculations. 相似文献
95.
Affolder T Akimoto H Akopian A Albrow MG Amaral P Amidei D Anikeev K Antos J Apollinari G Arisawa T Artikov A Asakawa T Ashmanskas W Azfar F Azzi-Bacchetta P Bacchetta N Bachacou H Bailey S de Barbaro P Barbaro-Galtieri A Barnes VE Barnett BA Baroiant S Barone M Battle C Bauer G Bedeschi F Belforte S Bell WH Bellettini G Bellinger J Benjamin D Bensinger J Beretvas A Berge JP Berryhill J Bhatti A Binkley M Bisello D Bishai M Blair RE Blocker C Bloom K Blumenfeld B Blusk SR Bocci A Bodek A 《Physical review letters》2002,88(7):071806
We present the first general search for new heavy particles, X, which decay via X --> WZ0 --> e(nu)+jj as a function of M(X) and Gamma(X) in pp collisions at square root[s] = 1.8 TeV. No evidence is found for production of X in 110 pb(-1) of data collected by the Collider Detector at Fermilab. General cross section limits are set at the 95% C.L. as a function of mass and width of the new particle. The results are further interpreted as mass limits on the production of new heavy charged vector bosons which decay via W' --> WZ0 in an extended gauge model as a function of the width, Gamma(W'), and mixing factor between the W' and the standard model W bosons. 相似文献
96.
Aaltonen T Adelman J Akimoto T Albrow MG Alvarez González B Amerio S Amidei D Anastassov A Annovi A Antos J Aoki M Apollinari G Apresyan A Arisawa T Artikov A Ashmanskas W Attal A Aurisano A Azfar F Azzi-Bacchetta P Azzurri P Bacchetta N Badgett W Barbaro-Galtieri A Barnes VE Barnett BA Baroiant S Bartsch V Bauer G Beauchemin PH Bedeschi F Bednar P Behari S Bellettini G Bellinger J Belloni A Benjamin D Beretvas A Beringer J Berry T Bhatti A Binkley M Bisello D Bizjak I Blair RE Blocker C 《Physical review letters》2008,100(10):101802
We have performed a search for B(s)(0) --> micro(+) micro(-) and B(0) --> micro(+) micro(-) decays in pp collisions at square root s = 1.96 TeV using 2 fb(-1) of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron Collider. The observed number of B(s)(0) and B0 candidates is consistent with background expectations. The resulting upper limits on the branching fractions are B(B(s)0) --> micro(+) micro(-)) <5.8 x 10(-8) and B(B(0) --> micro(+) micro(-))<1.8 x 10(-8) at 95% C.L. 相似文献
97.
This letter reports the first results on the coupled modulational instability of copropagating spin waves in a magnetic film. Strong instability was observed for the two waves with either attractive or repulsive nonlinearity. If the two waves have attractive nonlinearity, the instability leads to the formation of bright solitons. If the two waves have repulsive nonlinearity, the process results in the formation of black solitons. The instability was also observed for the two waves in separated attractive-repulsive nonlinearity regimes. 相似文献
98.
Affolder T Akimoto H Akopian A Albrow MG Amaral P Amendolia SR Amidei D Anikeev K Antos J Apollinari G Arisawa T Asakawa T Ashmanskas W Azfar F Azzi-Bacchetta P Bacchetta N Bailey MW Bailey S de Barbaro P Barbaro-Galtieri A Barnes VE Barnett BA Baroiant S Barone M Bauer G Bedeschi F Belforte S Bell WH Bellettini G Bellinger J Benjamin D Bensinger J Beretvas A Berge JP Berryhill J Bevensee B Bhatti A Binkley M Bisello D Bishai M Blair RE Blocker C Bloom K Blumenfeld B Blusk SR Bocci A Bodek A 《Physical review letters》2001,86(15):3233-3238
We present the first measurement of the ratio of branching fractions R identical withB(t-->Wb)/B(t-->Wq) from p_p collisions at sqrt[s] = 1.8 TeV. The data set corresponds to 109 pb(-1) of data recorded by the Collider Detector at Fermilab during the 1992-95 Tevatron run. We measure R = 0.94(+0.31)(-0.24)(stat+syst) or R>0.61 (0.56) at 90% (95)% C.L., in agreement with the standard model predictions. This measurement yields a limit on the Cabibbo-Kobayashi-Maskawa quark mixing matrix element /V(tb)/ under the assumption of three generations and unitarity. 相似文献
99.
Affolder T Akimoto H Akopian A Albrow MG Amaral P Amidei D Anikeev K Antos J Apollinari G Arisawa T Artikov A Asakawa T Ashmanskas W Azfar F Azzi-Bacchetta P Bacchetta N Bachacou H Bailey S de Barbaro P Barbaro-Galtieri A Barnes VE Barnett BA Baroiant S Barone M Bauer G Bedeschi F Belforte S Bell WH Bellettini G Bellinger J Benjamin D Bensinger J Beretvas A Berge JP Berryhill J Bhatti A Binkley M Bisello D Bishai M Blair RE Blocker C Bloom K Blumenfeld B Blusk SR Bocci A Bodek A Bokhari W 《Physical review letters》2001,87(13):131802
We report on a measurement of the mass dependence of the forward-backward charge asymmetry, A(FB), and production cross section d sigma/dM for e(+)e(-) pairs with mass M(ee)>40 GeV/c(2). The data sample consists of 108 pb(-1) of pp macro collisions at square root of s = 1.8 TeV taken by the Collider Detector at Fermilab during 1992-1995. The measured asymmetry and d sigma/dM are compared with the predictions of the standard model and a model with an extra Z' gauge boson. 相似文献
100.
Aihara H Alston-Garnjost M Avery RE Barbaro-Galtieri A Barker AR Barnes AV Barnett BA Bauer DA Bengtsson H Bintinger DL Bobbink GJ Bolognese TS Bross AD Buchanan CD Buijs A Cain MP Caldwell DO Clark AR Cowan GD Crane DA Dahl OI Derby KA Eastman JJ Eberhard PH Eisner AM Enomoto R Erné FC Fujii T Gary JW Gorn W Hauptman JM Hofmann W Huth JE Hylen J Kamae T Kaye HS Kees KH Kenney RW Kerth LT Ko W Koda RI Kofler RR Kwong KK Lander RL Langeveld WG Layter JG Linde FL Lindsey CS Loken SC Lu A Lu X 《Physical review letters》1986,57(8):945-948