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PHYSICAL REVIEW C, VOLUME 64, NUMBER 3 Selected Abstracts from Other Physical Review Journals Abstracts of papers which are published in other Physical Review journals and may be of interest to Physical Review C readers are printed here. The Editors of Physical Review C routinely scan the abstracts of Physical Review D papers. Appropriate abstracts of papers in other Physical Review journals may be included upon request. Polarization in hadronic ⌳ hyperon production and chiral-odd characterizing the vector and scalar 4-fermion interaction ␰ Ͻ twist-3 distribution. Y. Kanazawa and Yuji Koike, Department of ϵGV /GS . It is shown that for ␰ 0.4 matter is self-bound and for Physics, Niigata University, Ikarashi, Niigata 950-2181, Japan. ␰Ͻ0.65 it has a ®rst order phase transition of the liquid-gas type. ͑Received 3 April 2001; published 11 July 2001͒ The Gibbs conditions in the mixed phase are applied for the case of two chemical potentials associated with the baryon number and Polarization of the ⌳ hyperon produced with a large transverse electric charge. The characteristics of the quark stars are calculated momentum in unpolarized nucleon-nucleon collisions is analyzed in for ␰ϭ0, 0.5, and 1. It is found that the phase transition leads to a the framework of QCD factorization. We focus on the mechanism strong density variation at the surface of these stars. For ␰ϭ1 the in which the soft-gluon component of the chiral-odd spin- properties of quark stars show behaviors typical for neutron stars. independent twist-3 quark distribution EF(x,x) becomes a source of At ␰տ0.4 the stars near to the maximum mass have a large admix- the polarized quark fragmenting into the polarized ⌳. Our simple ture of strange quarks in their interiors. ͓Phys. Rev. D 64, 043005 model estimate for this contribution indicates that it gives rise to a ͑2001͔͒ signi®cant ⌳ polarization at large xF . This is in parallel with the observation that the soft gluon pole mechanism gives rise to a large → single transverse spin asymmetry in pion production at xF 1. ͓Phys. Rev. D 64, 034019 ͑2001͔͒ Standard model neutrinos as warm dark matter. Gian F. Giudice,1 Edward W. Kolb,2 Antonio Riotto,3 Dmitry V. Semikoz,4,5 1,5 1 Nucleon-nucleon bremsstrahlung of axions and pseudoscalar and Igor I. Tkachev, CERN Theory Division, CH- 2 particles from neutron-star matter. Naoki Iwamoto, Department 1211 Geneva 23, Switzerland, NASA/Fermilab Astrophysics Cen- of Physics and Astronomy, The University of Toledo, Toledo, ter, Fermi National Accelerator Laboratory, Batavia, Ohio 43606-3390 and Department of Advanced Materials Science, Illinois 60510-0500 and Department of Astronomy and Astrophys- Faculty of Engineering, Kagawa University, Takamatsu, ics, Enrico Fermi Institute, The University of Chicago, Chicago, 3 Kagawa 761-0396, Japan. ͑Received 16 February 2001; pub- Illinois 60637-1433, Scuola Normale Superiore, Piazza dei Cava- 4 lished 26 July 2001͒ lieri 7, I-56126 Pisa, Italy, Max Planck Insitut fuÈr Physik, FoÈ- hringer Ring 6, 80805 MuÈnchen, Germany, 5Institute for Nuclear The energy-loss rates of degenerate neutron-star matter due to Research of the Academy of Sciences of Russia, Moscow 117312, thermal bremsstrahlung of pseudoscalar particles and axions via Russia. ͑Received 22 December 2000; published 27 July 2001͒ neutron-proton collisions together with the mean-free path and the energy spectrum from neutron-neutron, neutron-proton, and Standard model neutrinos are not usually considered plausible neutron-neutron processes are calculated. Analytic expressions for dark matter candidates because the usual treatment of their decou- these quantities are obtained in the general case where the pseudo- pling in the early universe implies that their mass must be suf®- scalar particle couples to the proton and neutron with different ciently small to make them ``hot'' dark matter. In this paper we strengths and the protons and the neutrons have different Fermi show that decoupling of standard model neutrinos in low reheat momenta. These rates are compared with those of other authors. models may result in neutrino densities very much less than usually ͓Phys. Rev. D 64, 043002 ͑2001͔͒ assumed, and thus their mass may be in the keV range. Standard model neutrinos may therefore be warm dark matter candidates. ͓Phys. Rev. D 64, 043512 ͑2001͔͒ Strange quark stars within the Nambu±Jona-Lasinio model. M. Hanauske,1 L. M. Satarov,1,2 I. N. Mishustin, 1,2,3 H. StoÈcker,1 and W. Greiner,1 1Institut fuÈr Theoretische Physik, J. W. Goethe± Two-loop self-energy and multiple scattering at ®nite tempera- UniversitaÈt, D-60054 Frankfurt, Germany, 2The Kurchatov Insti- ture. J. I. Kapusta, School of Physics and Astronomy, University of tute, 123182 Moscow, Russia, 3The Niels Bohr Institute, DK-2100 Minnesota, Minneapolis, Minnesota 55455; S. M. H. Wong, De- Copenhagen O, Denmark. ͑Received 16 January 2001; published 30 partment of Physics, Ohio State University, Columbus, Ohio 43210. July 2001͒ ͑Received 5 March 2001; published 20 July 2001͒ We investigate the properties of charge-neutral ␤-equilibrium One- and two-loop self-energies are worked out explicitly for a cold quark matter within the Nambu±Jona-Lasinio model. The cal- heavy scalar ®eld interacting weakly with a light self-interacting culations are carried out for different ratios of coupling constants scalar ®eld at ®nite temperature. The ring or daisy diagrams and a i SELECTED ABSTRACTS PHYSICAL REVIEW C 64 set of necklace diagrams can be summed simultaneously. This 60616, 6Los Alamos National Laboratory, Los Alamos, New simple model serves to illustrate the connection between multiloop Mexico 87545, 7Louisiana State University, Baton Rouge, Louisi- self-energy diagrams and multiple scattering in a medium. ͓Phys. ana 70803, 8New Mexico State University, Las Cruces, New Rev. D 64, 045008 ͑2001͔͒ Mexico 88003, 9Oak Ridge National Laboratory, Oak Ridge, Ten- nessee 37831, 10Texas A & M University, College Station, Texas 77843, 11Valparaiso University, Valparaiso, Indiana 46383. ͑Re- ceived 14 March 2001; published 10 August 2001͒ Spontaneous parity violation in QCD at ®nite temperature: On Measurements of the ratio of Drell-Yan yields from an the inapplicability of the Vafa-Witten theorem. Thomas D. Co- 800 GeV/c proton beam incident on liquid hydrogen and deute- hen, Department of Physics, University of Maryland, College Park, rium targets are reported. Approximately 360 000 Drell-Yan muon Maryland 20742-4111. ͑Received 30 January 2001; published 30 pairs remained after all cuts on the data. From these data, the ratio July 2001͒ of down antiquark (Åd) to up (Åu) antiquark distributions in the pro- The generalization of the Vafa-Witten theorem, ruling out parity ton sea is determined over a wide range in Bjorken-x. These results violation to QCD at ®nite temperature is considered. It is shown con®rm previous measurements by E866 and extend them to lower that this generalization of the theorem rules out Lorentz-invariant x. From these data, (ÅdϪÅu) and ͐(ÅdϪÅu)dx are evaluated for parity violating operators from spontaneously acquiring vacuum ex- 0.015ϽxϽ0.35. These results are compared with parametrizations pectation values. However, it does not rule out Lorentz-noninvariant of various parton distribution functions, models and experimental parity-violating operators from acquiring expectation values. Other results from NA51, NMC and HERMES. ͓Phys. Rev. D 64, 052002 situations, where the theorem is inapplicable, are also discussed. ͑2001͔͒ ͓Phys. Rev. D 64, 047704 ͑2001͔͒ Discrete ¯avor symmetries and mass matrix textures. M. S. Relativistic corrections to the electromagnetic polarizabilities of Berger and Kim Siyeon, Physics Department, Indiana University, compound systems. R. N. Lee and A. I. Milstein, Budker Institute Bloomington, Indiana 47405. ͑Received 31 May 2000; revised of Nuclear Physics, 630090 Novosibirsk, Russia; M. Schumacher, manuscript received 22 March 2001; published 1 August 2001͒ Zweites Physikalisches Institut, UniversitaÈt GoÈttingen, D-37073 GoÈttingen, Germany. ͑Received 4 February 2001; published 20 Au- We show how introducing discrete Abelian ¯avor symmetries can gust 2001͒ produce texture zeros in the fermion mass matrices, while preserv- ing the correct relationships with the low-energy data on quark and The low-energy amplitude of Compton scattering on the bound lepton masses. We outline a procedure for de®ning texture zeros as state of two charged particles of arbitrary masses, charges, and spins suppressed entries in Yukawa matrices. These texture zeros can ac- is obtained. A case in which the bound state exists due to electro- count for the coexistence of the observed large mixing in atmo- 2 magnetic interaction is considered. The term, proportional to ␻ , is spheric neutrino oscillations with a hierarchy in the neutrino obtained taking into account the ®rst relativistic correction. It is masses, and offer the possibility of alignment of the quark and shown that the complete result for this correction differs essentially squark mass matrices, thus giving a solution to the supersymmetric from the commonly used term ⌬␣, proportional to the rms charge ¯avor problem. A requirement that the ¯avor symmetry commutes radius of the system. We propose that the same situation can take with the SU(5) grand uni®ed group can be used to explain the place in the more complicated case of hadrons. ͓Phys. Rev. A 64, lepton mass hierarchies as well as the neutrino parameters, includ- 032507 ͑2001͔͒ ing the large mixing observed in the atmospheric neutrino data. We present one such model that yields a large atmospheric neutrino mixing angle, as well as a solar neutrino mixing angle of order ␭ Ӎ0.22. ͓Phys. Rev. D 64, 053006 ͑2001͔͒ Improved measurement of the ÅdÕÅu asymmetry in the nucleon sea. R. S. Towell,1,6 P. L. McGaughey,6 T. C. Awes,9 M. E. Beddo,8 M. L. Brooks,6 C. N. Brown,3 J. D. Bush,1 T. A. Carey,6 T. H. Chang,8 W.

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