We present a new NLO QCD analysis of the world data on inclusive polarized deep inelastic scattering. Comparing to our previous analysis: i) the values of g A and a 8 = 3F −D are updated ii)the MRST'99 instead of the MRST'98 parametrization for the input unpolarized parton densities is used and iii) the recent SLAC E155 proton data on the spin asymmetry A1 are included in the analysis. A new set of polarized parton densities is extracted from the data and the sensitivity of the results to different positivity constraints is discussed.

The Atmospheric Chemistry Suite (ACS) package is an element of the Russian contribution to the ESA-Roscosmos ExoMars 2016 Trace Gas Orbiter (TGO) mission. ACS consists of three separate infrared spectrometers, sharing common mechanical, electrical, and thermal interfaces. This ensemble of spectrometers has been designed and developed in response to the Trace Gas Orbiter mission objectives that specifically address the requirement of high sensitivity instruments to enable the unambiguous detection of trace gases of potential geophysical or biological interest. For this reason, ACS embarks a set of instruments achieving simultaneously very high accuracy (ppt level), very high resolving power (>10,000) and large spectral coverage (0.7 to 17 µm-the visible to thermal infrared range). The near-infrared (NIR) channel is a versatile spectrometer covering the 0.7-1.6 µm spectral range with a resolving power of ∼20,000. NIR employs the combination of an echelle grating with an AOTF (Acousto-Optical Tunable Filter) as diffraction order selector. This channel will be mainly operated in solar occultation and nadir, and can also perform limb observations. The scientific goals of NIR are the measurements of water vapor, aerosols, and dayside or night side airglows. The mid-infrared (MIR) channel is a cross-dispersion echelle instrument dedicated to solar occultation measurements in the 2.2-4.4 µm range. MIR achieves a resolving power of >50,000. It has been designed to accomplish the most sensitive measurements ever of the trace gases present in the Martian atmosphere. The thermal-infrared channel (TIRVIM) is a 2-inch double pendulum Fourier-transform spectrometer encompassing the spectral range of 1.7-17 µm with apodized resolution varying from 0.2 to 1.3 cm −1 . TIRVIM is primarily dedicated to profiling temperature from the surface up to ∼60 km and to monitor aerosol abundance in nadir. TIRVIM also has a limb and solar occultation capability. The technical concept of the instrument, its accommodation on the spacecraft, the optical designs as well as some of the calibrations, and the expected performances for its three channels are described.

We have re-analyzed the world data on inclusive polarized DIS, in both NLO and LO QCD, including the new HERMES and COMPASS data. The updated NLO polarized densities are given in both the MS and JET schemes. The impact of the new data on the results is discussed.PACS numbers: 13.60. Hb, 13.88+e, 14.20.Dh Since the famous European Muon Collaboration (EMC) experiment [1] at CERN in 1987, substantial efforts, both experimental and theoretical, have been devoted to understanding the partonic spin structure of the nucleon, i.e., how the nucleon spin is built up out from the intrinsic spin and orbital angular momentum of its constituents, quarks and gluons. Our present knowledge about the spin structure of the nucleon comes mainly from polarized inclusive and semi-inclusive DIS experiments at SLAC, CERN, DESY and JLab, polarized proton-proton collisions at RHIC and polarized photoproduction experiments. The determination of the longitudinal polarized parton densities in QCD is one of the important and best studied aspects of this knowledge.In this Brief Report we present an updated version of our Set 1 and Set 2 NLO QCD polarized parton densities in both the MS and the JET (or so-called chirally In QCD the spin structure function g 1 has the following form (Q 2 >> Λ 2 ):where "LT" denotes the leading twist (τ = 2) contribution to g 1 , while "HT" denotes the contribution to g 1 arising from QCD operators of higher twist, namely τ ≥ 3. In Eq.(1) (the nucleon target label N is dropped)where g 1 (x, Q 2 ) pQCD is the well known (logarithmic in Q 2 ) pQCD contribution and2 ) are the calculable [8] kinematic target mass corrections, which effectively belong to the LT term. In Eq.(1)where h(x, Q 2 ) are the dynamical higher twist (τ = 3 and τ = 4) corrections to g 1 , whichare related to multi-parton correlations in the nucleon. The latter are non-perturbative effects and cannot be calculated without using models.1 Let us recall that the Set 1 polarized parton densities correspond to fits to g 1 /F 1 and A 1 (≈ g 1 /F 1 ) data (so called 'g 1 /F 1 ' fits):where for the structure functions g 1 and F 1 their leading twist NLO QCD expressions are used. (Why this method is incorrect for extracting the LO polarized PDs, is discussed in Ref. [11].) The Set 2 polarized PD correspond to fits to g 1 /F 1 and A 1 data where the experimental data for the unpolarized structure functionAs usual, F 1 is replaced by its expression in terms of the usually extracted from unpolarized DIS experiments F 2 and R and phenomenological parametrizations of the experimental data for F 2 (x, Q 2 ) [9] and the ratio R(x, Q 2 ) of the longitudinal to transverse γN cross-sections [10] are used. Note that such a procedure is equivalent to a fit to g 1 data themselves and we will refer to these as '(g As in our previous analyses [3,12], for the input LO and NLO polarized parton densities at Q 2 0 = 1 GeV 2 we have adopted a simple parametrizationwhere on the RHS of (6) Note that this convention affects the results for the valence parton densiti...

We briefly summarize the outcomes of our recent improved fits to the experimental data of CCFR collaboration for xF 3 structure function of νN deepinelastic scattering at the next-to-next-to-leading order. Special attention is paid to the extraction of αs(M Z ) and the parameter of the infrared renormalon model for 1/Q 2 -correction at different orders of perturbation theory. The results can be of interest for planning similar studies using possible future data of Neutrino Factories.

We have re-analyzed the world data on inclusive polarized DIS including the very precise CLAS proton and deuteron data, as well as the latest COMPASS data on the asymmetry A d 1 , and have studied the impact of these data on polarized parton densities and higher twist effects. We demonstrate that the low Q 2 CLAS data improve essentially our knowledge of higher twist corrections to the spin structure function g1, while the large Q 2 COMPASS data influence mainly the strange quark density. In our new analysis we find that a negative polarized gluon density, or one that changes sign as a function of x, cannot be ruled out on the basis of the present DIS data.