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101.
D. Aston M. Atkinson R. Bailey A.H. Ball B. Bouquet G.R. Brookes J. Br?ring P.J. Bussey D. Clarke A.B. Clegg B. dAlmagne G. de Rosny B. Diekmann A. Donnachie M. Draper B. Drevillon I.P. Duerdoth J.-P. Dufey T.P. Yiou 《Nuclear Physics B》1981,189(1):15-39
Measurements of the reaction γp → pπ+π?π+π? are presented, in which π+π?π+π? systems with masses up to 3 GeV are produced from fragmentation of the incident photon. The reaction is dominated by production of the large peak of the ?′(1600) meson and, at higher masses ?2 GeV, y production of jet-like 4π systems. The ?′(1600) meson is produced by a predominantly s-channel helicity conserving mechanism. At higher masses there are also indications of ?π peaks, of masses 1.3 GeV (the A2 meson) and 1.75 GeV, produced with a recoiling π meson by a mechanism consistent with the Deck effect. 相似文献
102.
James E. Draper 《Zeitschrift für Physik A Hadrons and Nuclei》1982,308(4):289-299
The nonrelativistic doubly differential cross section for electrons ejected from atoms by a massive beam of bare ions is derived in the binary encounter approximation. For cases already published the results sometimes differ by as much as a factor of 80 from those of Bonsen and Vriens, although the agreement should be exact. The case when the struck electron was initially very slow or stationary is also considered. Methods are presented for visualizing the kinematics including questions of minimum and maximum initial electron velocity for a given energy transfer. Also presented is a graphical means of visualizing the origin of the binary peak and of other effects for various atomic numbersZ of the target and various projectile velocities. 相似文献
103.
104.
D. Aston M. Atkinson R. Bailey A.H. Ball B. Bouquet G.R. Brookes J. Br?ring P.J. Bussey D. Clarke A.B. Clegg D. dAlmagne G. de Rosny B. Diekmann M. Draper B. Drevillon I.P. Duerdoth J.-P. Dufey T.P. Yiou 《Physics letters. [Part B]》1980,93(4):517-520
Exclusive and inclusive photoproduction (with ? 2 accompanying charged particles) have been measured in the photon energy range 44–70 GeV. The exclusive process shows no prominent features; the inclusive process shows evidence for S(1936) production as a resonant-like structure with mass 1930 ± 2 MeV and width 12 ± 7 MeV. 相似文献
105.
106.
Richard T Libby Gareth R Howell Iok-Hou Pang Olga V Savinova Adrienne K Mehalow Joseph W Barter Richard S Smith Abbot F Clark Simon WM John 《BMC neuroscience》2007,8(1):108
Background
Nitric oxide synthase 2 (NOS2) contributes to neural death in some settings, but its role in glaucoma remains controversial. NOS2 is implicated in retinal ganglion cell degeneration in a rat glaucoma model in which intraocular pressure (IOP) is experimentally elevated by blood vessel cauterization, but not in a rat glaucoma model where IOP was elevated by injection of hypertonic saline. To test the importance of NOS2 for an inherited glaucoma, in this study we both genetically and pharmacologically decreased NOS2 activity in the DBA/2J mouse glaucoma model. 相似文献107.
Zorbas V Smith AL Xie H Ortiz-Acevedo A Dalton AB Dieckmann GR Draper RK Baughman RH Musselman IH 《Journal of the American Chemical Society》2005,127(35):12323-12328
We have previously demonstrated that a designed amphiphilic peptide helix, denoted nano-1, coats and debundles single-walled carbon nanotubes (SWNTs) and promotes the assembly of these coated SWNTs into novel hierarchical structures via peptide-peptide interactions. The purpose of this study is to better understand how aromatic content impacts interactions between peptides and SWNTs. We have designed a series of peptides, based on the nano-1 sequence, in which the aromatic content is systematically varied. Atomic force microscopy measurements and optical absorption spectroscopy reveal that the ability to disperse individual SWNTs increases with increasing aromatic residues in the peptide. Altogether, the results indicate that pi-stacking interactions play an important role in peptide dispersion of SWNTs. 相似文献
108.
Panitkin SY Ajitanand NN Alexander J Anderson M Best D Brady FP Case T Caskey W Cebra D Chance J Chung P Cole B Crowe K Das A Draper J Gilkes M Gushue S Heffner M Hirsch A Hjort E Huo L Justice M Kaplan M Keane D Kintner J Klay J Krofcheck D Lacey R Lauret J Lisa MA Liu H Liu YM McGrath R Milosevich Z Odyniec G Olson D Pinkenburg C Porile N Rai G Ritter HG Romero J Scharenberg R Schroeder LS Srivastava B Stone NT Symons TJ Wang S Wells R Whitfield J Wienold T Witt R Wood L Yang X Zhang WN 《Physical review letters》2001,87(11):112304
We report a particle source imaging analysis based on two-pion correlations in high multiplicity Au+Au collisions at beam energies between 2A and 8A GeV. We apply the imaging technique introduced by Brown and Danielewicz, which allows a model-independent extraction of source functions with useful accuracy out to relative pion separations of about 20 fm. The extracted source functions have Gaussian shapes. Values of source functions at zero separation are almost constant across the energy range under study. Imaging results are found to be consistent with conventional source parameters obtained from a multidimensional Hanburg-Brown-Twiss analysis. 相似文献
109.
Adler C Ahammed Z Allgower C Amonett J Anderson BD Anderson M Averichev GS Balewski J Barannikova O Barnby LS Baudot J Bekele S Belaga VV Bellwied R Berger J Bichsel H Bland LC Blyth CO Bonner BE Boucham A Brandin A Bravar A Cadman RV Caines H Calderón de la Barca Sánchez M Cardenas A Carroll J Castillo J Castro M Cebra D Chaloupka P Chattopadhyay S Chen Y Chernenko SP Cherney M Chikanian A Choi B Christie W Coffin JP Cormier TM Cramer JG Crawford HJ Deng WS Derevschikov AA Didenko L Dietel T 《Physical review letters》2002,89(27):272302
The STAR Collaboration reports the first observation of exclusive rho(0) photoproduction, AuAu-->AuAurho(0), and rho(0) production accompanied by mutual nuclear Coulomb excitation, AuAu-->Au*Au*rho(0), in ultraperipheral heavy-ion collisions. The rho(0) have low transverse momenta, consistent with coherent coupling to both nuclei. The cross sections at sqrt[s(NN)]=130 GeV agree with theoretical predictions treating rho(0) production and Coulomb excitation as independent processes. 相似文献
110.
Chung P Ajitanand NN Alexander JM Anderson M Best D Brady FP Case T Caskey W Cebra D Chance JL Cole B Crowe K Das A Draper JE Gilkes ML Gushue S Heffner M Hirsch AS Hjort EL Huo L Justice M Kaplan M Keane D Kintner JC Klay J Krofcheck D 《Physical review letters》2000,85(5):940-943
We have measured the sideward flow of neutral strange ( K(0)(s)) mesons in 6A GeV Au+Au collisions. A prominent antiflow signal is observed for an impact parameter range ( b less, similar7 fm) which spans central and midcentral events. Since the K(0)(s) scattering cross section is relatively small in nuclear matter, this observation suggests that the in-medium kaon vector potential plays an important role in high density nuclear matter. 相似文献