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1. chinaXiv:201703.00258 [pdf]

PRELIMINARY PERFORMANCE SIMULATION OF MICROWAVE IMAGER COMBINED ACTIVE PASSIVE – A NEW INSTRUMENT FOR CHINESE SALINITY MISSION

Xiaobin Yin; Lanjie Zhang; Hao Liu; Risheng Yun; Lin Wu; Xingou Xu; Di Zhu
Subjects: Geosciences >> Space Physics

A 1-D interferometric system at 1.4GHz, 6.9GHz, 18.7 GHz and 23.8GHz combined with a scatterometer at 1.26GHz, called microwave imager combined active/passive (MICAP), has been proposed to retrieve sea surface salinity (SSS) and to reduce geophysical errors due to surface roughness and sea surface temperature (SST). The MICAP will be a candidate payload onboard the Ocean Salinity Satellite of China. The sensitivity of active/passive microwave observations to SSS, SST and wind is analyzed and the stability requirement of the instruments is estimated, with the objective of designing an optimized satellite instrument, dedicated to an "all-weather" estimate of the SSS with high accuracy from space.

submitted time 2017-03-10 Hits1442Downloads777 Comment 0

2. chinaXiv:201609.01029 [pdf]

The effect of the chiral chemical potential on the chiral phase transition in the NJL model with different regularization schemes

Lang Yu1; Hao Liu; Mei Huang
Subjects: Physics >> Nuclear Physics

We study the chiral phase transition in the presence of the chiral chemical potential?μ5?using the two-flavor Nambu--Jona-Lasinio model. In particular, we analyze the reason why one can obtain two opposite behaviors of the chiral critical temperature as a function of?μ5?in the framework of different regularization schemes. We compare the modifications of the chiral condensate and the critical temperature due to?μ5?in different regularization schemes, analytically and numerically. Finally, we find that, for the conventional hard-cutoff regularization scheme, the increasing dependence of the critical temperature on the chiral chemical potential is an artifact, which is caused by the fact that it does not include complete contribution from the thermal fluctuations. When the thermal contribution is fully taken into account, the chiral critical temperature should decrease with?μ5.

submitted time 2016-09-14 Hits778Downloads453 Comment 0

3. chinaXiv:201609.00975 [pdf]

Survival of charged rho condensation at high temperature and density

Hao Liu; Lang Yu; Mei Huang
Subjects: Physics >> Nuclear Physics

The charged vector?ρ?mesons in the presence of external magnetic fields at finite temperature?T?and chemical potential?μ?have been investigated in the framework of the Nambu--Jona-Lasinio model. We compute the masses of charged?ρ?mesons numerically as a function of the magnetic field for different values of temperature and chemical potential. The self-energy of the?ρ?meson contains the quark-loop contribution, i.e. the leading order contribution in?1/Nc?expansion. The charged?ρ?meson mass decreases with the magnetic field and drops to zero at a critical magnetic field?eBc, which means that the charged vector meson condensation, i.e. the electromagnetic superconductor can be induced above the critical magnetic field. Surprisingly, it is found that the charged?ρcondensation can even survive at high temperature and density. At zero temperature, the critical magnetic field just increases slightly with the chemical potential, which indicates that the charged?ρ?condensation might occur inside compact stars. At zero density, in the temperature range?0.2?0.5?GeV, the critical magnetic field for charged?ρcondensation is in the range of?0.2?0.6?GeV2, which indicates that the high temperature electromagnetic superconductor could be created at LHC.

submitted time 2016-09-14 Hits754Downloads434 Comment 0

4. chinaXiv:201609.00078 [pdf]

Majorana Neutrino Masses from Neutrinoless Double-Beta Decays and Lepton-Number-Violating Meson Decays

Jun-Hao Liu; Jue Zhang; Shun Zhou
Subjects: Physics >> Nuclear Physics

The Schechter-Valle theorem states that a positive observation of neutrinoless double-beta (0νββ) decays implies a finite Majorana mass term for neutrinos when any unlikely fine-tuning or cancellation is absent. In this note, we reexamine the quantitative impact of the Schechter-Valle theorem, and find that current experimental lower limits on the half-lives of?0νββ-decaying nuclei have placed a restrictive upper bound on the Majorana neutrino mass?|δmeeν|<7.43×10?29?eV?radiatively generated at the four-loop level. Furthermore, we generalize this quantitative analysis of?0νββ?decays to that of the lepton-number-violating (LNV) meson decays?M?→M′++??α+??β?(for?α,?β?=?e?or?μ). Given the present upper limits on these rare LNV decays, we have derived the loop-induced Majorana neutrino masses?|δmeeν|<9.7×10?18?eV,?|δmeμν|<1.6×10?15?eV?and?|δmμμν|<1.0×10?12?eV?from?K?→π++e?+e?,?K?→π++e?+μ??and?K?→π++μ?+μ?, respectively. A partial list of radiative neutrino masses from the LNV decays of?D,?Ds?and?B?mesons is also given.

submitted time 2016-09-06 Hits875Downloads504 Comment 0

5. chinaXiv:201609.00026 [pdf]

Possible formation of high temperature superconductor at early stage of heavy-ion collisions

Hao Liu; Lang Yu; Maxim Chernodu; Mei Huang
Subjects: Physics >> Nuclear Physics

We investigate the effect of the inverse magnetic catalysis (IMC) on the charged?ρ?meson condensation at finite temperature in the framework of the Nambu--Jona-Lasinio model, where mesons are calculated to the leading order of?1/Nc?expansion by summing up infinity quark-loops. IMC for chiral condensate has been considered in three different ways, i.e. fitting Lattice data, using the running coupling constant and introducing the chiral chemical potential, respectively. It is observed that, with no IMC effect included, the critical magnetic field?eBc?for charged?ρ?condensation increases monotonically with the temperature. However, including IMC substantially affects the polarized charged?ρ?condensation around the critical temperature?Tc?of chiral phase transition, the critical magnetic field?eBc?for charged?ρ?condensation decreases with the temperature firstly, reaches to a minimum value around?Tc, then increases with the temperature. Our calculation indicates that the charged?ρ?condensation can exist in the temperature region of?1?1.5Tc?with critical magnetic field?eBc?0.15?0.3GeV2, which suggests that high temperature superconductor might be created through non-central heavy ion collisions at LHC energies. We also show that a growing electric conductivity in early stage of non-central heavy-ion collisions substantially delays the decay of strong magnetic field, which is helpful for the formation of the high temperature superconductor.

submitted time 2016-09-02 Hits1013Downloads529 Comment 0

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