We report on measurements of the neutron spin asymmetries A n 1,2 and polarized structure functions g n 1,2 at three kinematics in the deep inelastic region, with x = 0.33, 0.47 and 0.60 and Q 2 = 2.7, 3.5 and 4.8 (GeV/c) 2 , respectively. These measurements were performed using a 5.7 GeV longitudinally-polarized electron beam and a polarized 3 He target. The results for A n 1 and g n 1 at x = 0.33 are consistent with previous world data and, at the two higher x points, have improved the precision of the world data by about an order of magnitude. The new A n 1 data show a zero crossing around x = 0.47 and the value at x = 0.60 is significantly positive. These results agree with a next-to-leading order QCD analysis of previous world data. The trend of data at high x agrees with constituent quark model predictions but disagrees with that from leading-order perturbative QCD (pQCD) assuming hadron helicity conservation. Results for A n 2 and g n 2 have a precision comparable to the best world data in this kinematic region. Combined with previous world data, the moment d n 2 was evaluated and the new result has improved the precision of this quantity by about a factor of two. When combined with the world proton data, polarized quark distribution functions were extracted from the new g n 1 /F n 1 values based on the quark parton model. While results for ∆u/u agree well with predictions from various models, results for ∆d/d disagree with the leading-order pQCD prediction when hadron helicity conservation is imposed.

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We have measured the neutron spin asymmetry A(n)(1) with high precision at three kinematics in the deep inelastic region at x=0.33, 0.47, and 0.60, and Q(2)=2.7, 3.5, and 4.8 (GeV/c)(2), respectively. Our results unambiguously show, for the first time, that A(n)(1) crosses zero around x=0.47 and becomes significantly positive at x=0.60. Combined with the world proton data, polarized quark distributions were extracted. Our results, in general, agree with relativistic constituent quark models and with perturbative quantum chromodynamics (PQCD) analyses based on the earlier data. However they deviate from PQCD predictions based on hadron helicity conservation.

Trends in astronomical publication have traditionally been studied by examining the few thousand papers published in a few selected journals within a few selected years. With the development of comprehensive bibliographic databases such as ADS and SIMBAD, publication trends can now be studied using tens of thousands of papers published in a number of refereed astronomy journals. The ADS has extensive bibliographic information on almost every paper published in seven major astronomy journals over the past two decades; the SIMBAD database can be used to verify critical bibliographic information such as the number of authors and the length of the papers. Here we present results of a study of astronomical publication trends using 76,000 papers published in A&A, A&AS, AJ, ApJ, ApJS, MNRAS, and PASP between 1975 and. Two trends are particularly interesting: the fraction of single-author papers has decreased by about a factor of three in the last 20 years, while astronomical papers with niore than 50 authors have become increasingly common since 1990.

The Compton double-polarization observable 2z has been measured for the first time in the (1232) resonance region using a circularly polarized photon beam incident on a longitudinally polarized proton target at the Mainz Microtron. This paper reports these results, together with the model-dependent extraction of four proton spin polarizabilities from fits to additional asymmetry data using either a dispersion relation calculation or a baryon chiral perturbation theory calculations with the weighted average of these two fits resulting in γ E 1E 1 = −2.87 ± 0.52, γ M1M1 = 2.70 ± 0.43, γ E 1M2 = −0.85 ± 0.72, and γ M1E 2 = 2.04 ± 0.43, in units of 10 −4 fm 4 .