113400995
Vorticity and magnetic field production in relativistic ideal fluids
In the framework of relativistic ideal hydrodynamics, we study the production mechanism for vorticity and magnetic field in relativistic ideal fluids. It is demonstrated that in the uncharged fluids the thermal vorticity will always satisfy the Kelvin's theorem and the circulation must be conserved. However, in the charged fluids, the vorticity and magnetic field can be produced by the interaction between the entropy gradients and the fluid velocity gradients. Especially, in the multiple charged fluids, the vorticity and magnetic field can be produced by the interaction between the inhomogeneous charge density ratio and the fluid velocity gradients even if the entropy distribution is homogeneous, which provides another mechanism for the production of vorticity and magnetic field in relativistic plasmas or in the early universe.
118485729
Chirality in odd-A Rh isotopes within the triaxial particle rotor model
By adopting the fully quantal triaxial particle-rotor model, the candidate chiral doublet bands in odd-A nuclei {sup 103}Rh and {sup 105}Rh with {pi}g{sub 9/2}{sup -1} x {nu}h{sub 11/2}{sup 2} configuration are studied. For the doublet bands in both nuclei, agreement is excellent for the observed energies over the entire spin range and B(M1)/B(E2) at higher spin range. The evolution of the chiral geometry with angular momentum is discussed in detail by using the angular momentum components and their probability distributions. Chirality is found to change from chiral vibration to nearly static chirality at spin I=37/2 and back to another type of chiral vibration at higher spin. The influence of the triaxial deformation {gamma} is also studied.
124565590
High-spin states in near-spherical Y-88
123285492
Examining B(M1) staggering as a fingerprint for chiral doublet bands
The electromagnetic transitions of the doublet bands with different triaxiality parameter gamma are discussed in the particle rotor model with pi Th(11/2) circle times vh(11/2)(-1) configuration. It is found that B(M1) staggering as well as the resulting B(M1)/B(E2) and B(M1)(in)/B(M1)(out) staggering are sensitive to the triaxiality parameter gamma, and they associate strongly with the characters of nuclear chirality for 15 degrees <= gamma <= 30 degrees, i.e., the staggering is weak in the chiral vibration region while strong in the static chirality region. For partner bands with near degenerate energy spectra and similar B(M1) and B(E2) transitions, the strong B(M1) staggering can be used as a fingerprint for the static chirality.
120766563
New insight into the shape coexistence and shape evolution of Yb-157
High-spin states in Yb-157 have been populated in the Sm-144( O-16,3n)Yb-157 fusion-evaporation reaction at a beam energy of 85 MeV. Two rotational bands built on the nu f(7/2) and nu h(9/2) intrinsic states, respectively, have been established for the first time. The newly observed nu f(7/2) band and previously known nu i(13/2) band in Yb-157 are discussed in terms of total Routhian surface methods and compared with the structures in the neighboring N = 87 isotones. The structural characters observed in Yb-157 provide evidence for shape coexistence of three distinct shapes: prolate, triaxial, and oblate. At higher spins, both the nu f(7/2) band and nu i(13/2) band in Yb-157 undergo a shape evolution with sizable alignments occurring.
3923904
Top-quark mass measurement using events with missing transverse energy and jets at CDF.
We present a measurement of the top-quark mass using a sample of t ̄t events in 5.7 fb(-1) of integrated luminosity from p ̄p collisions at the Fermilab Tevatron with √s=1.96 TeV and collected by the CDF II Detector. We select events having large missing transverse energy, and four, five, or six jets with at least one jet tagged as coming from a b quark, and reject events with identified charged leptons. This analysis considers events from the semileptonic t ̄t decay channel, including events that contain tau leptons. The measurement is based on a multidimensional template method. We fit the data to signal templates of varying top-quark masses and background templates, and measure a top-quark mass of M(top)=172.32±2.4(stat)±1.0(syst)  GeV/c(2).
41231566
Quantitative Analysis of CME Deflections in the Corona
In this paper, ten CME events viewed by the STEREO twin spacecraft are analyzed to study the deflections of CMEs during their propagation in the corona. Based on the three-dimensional information of the CMEs derived by the graduated cylindrical shell (GCS) model (Thernisien, Howard, and Vourlidas in Astrophys. J.652, 1305, 2006), it is found that the propagation directions of eight CMEs had changed. By applying the theoretical method proposed by Shen et al. (Solar Phys.269, 389, 2011) to all the CMEs, we found that the deflections are consistent, in strength and direction, with the gradient of the magnetic energy density. There is a positive correlation between the deflection rate and the strength of the magnetic energy density gradient and a weak anti-correlation between the deflection rate and the CME speed. Our results suggest that the deflections of CMEs are mainly controlled by the background magnetic field and can be quantitatively described by the magnetic energy density gradient (MEDG) model.
123048219
Measurement of the top quark mass in the dilepton channel using m(T2) at CDF
We present measurements of the top quark mass using m(T2), a variable related to the transverse mass in events with two missing particles. We use the template method applied to t (t) over bar dilepton events produced in p (p) over bar collisions at Fermilab's Tevatron Collider and collected by the CDF detector. From a data sample corresponding to an integrated luminosity of 3.4 fb(-1), we select 236 t (t) over bar candidate events. Using the m(T2) distribution, we measure the top quark mass to be M-top = 168.0(-4.0)(4.8)(stat) +/- 2.9(syst) GeV/c(2). By combining m(T2) with the reconstructed top quark mass distributions based on a neutrino weighting method, we measure M-top = 169.3 +/- 2.7(stat) +/- 3.2(syst) GeV/c(2). This is the first application of the m(T2) variable in a mass measurement at a hadron collider.
119117966
Is there a maximum magnetic field in QED
Abstract It was recently conjectured by Shabad and Usov that there exists in QED a maximum magnetic field of 10 42 G , above which the magnetized vacuum becomes unstable. Using a nonperturbative analysis that consistently incorporates the effective electron mass and the screening effect in a strong magnetic field, we show that the conjectured phenomenon of positronium collapse never takes place. Thus, there does not exist a maximum magnetic field in QED and the magnetized vacuum is stable for all values of the magnetic field.
122255934
PROTON BRANCH OF MODIFIED URCA PROCESS IN STRONG MAGNETIC FIELD AND SUPERFLUIDITY OF NEUTRON STAR CORES
The modified URCA process produces efficient neutrino energy losses in neutron star cores, and has been shown to go via neutron and proton branches. Based on the improved electron chemical potential and critical temperature of superfluidity, the effects of strong magnetic field and superfluidity on the proton branch of modified URCA process are investigated simultaneously in this paper. The results show that strong magnetic field enhances the neutrino emissivities compared to the case in zero magnetic field, and superfluidity reduces the emissivities significantly. For the total neutrino emissivities, the magnetic field is dominant at the initial stage of neutron star cooling, but the superfluidity becomes crucial as the temperature drops below the critical temperature.