Magnetic Activity and Parameters of 43 Flare Stars in the GWAC Archive

In the archive of the Ground Wide Angle Camera(GWAC),we found 43 white light flares from 43 stars,among which,three are sympathetic or homologous flares,and one of them also has a quasi-periodic pulsation with a period of 13.0±1.5 minutes.Among these 43 flare stars,there are 19 new active stars and 41 stars that have available TESS and/or K2 light curves,from which we found 931 stellar flares.We also obtained rotational or orbital periods of 34 GWAC flare stars,of which 33 are less than 5.4 days,and ephemerides of three eclipsing binaries from these light curves.Combining with low resolution spectra from LAMOST and the Xinglong 2.16 m telescope,we found that L_(Hα)/L_(bol) are in the saturation region in the rotation-activity diagram.From the LAMOST medium-resolution spectrum,we found that Star#3(HAT 178-02667)has double Hαemissions which imply it is a binary,and two components are both active stars.Thirteen stars have flare frequency distributions(FFDs)from TESS and/or K2 light curves.These FFDs show that the flares detected by GWAC can occur at a frequency of 0.5to 9.5 yr^(-1).The impact of flares on habitable planets was also studied based on these FFDs,and flares from some GWAC flare stars may produce enough energetic flares to destroy ozone layers,but none can trigger prebiotic chemistry on their habitable planets.

The mini-GWAC optical follow-up of gravitational wave alerts – results from the O2 campaign and prospects for the upcoming O3 run

The second(O2)observational campaign of gravitational waves(GWs)organized by the LIGO/Virgo Collaborations has led to several breakthroughs such as the detection of GW signals from merger systems involving black holes or neutrons stars.During O2,14 GW alerts were sent to the astronomical community with sky regions mostly covering over hundreds of square degrees.Among them,six were finally confirmed as real astrophysical events.Since 2013,a new set of ground-based robotic telescopes called Ground-based Wide Angle Camera system(GWAC)project and its pathfinder mini-GWAC has been developed to contribute to the various challenges of multi-messenger and time domain astronomy.The GWAC system is built up in the framework of the ground-segment system of the SVOM mission that will be devoted to the study of the multi-wavelength transient sky in the next decade.During O2,only the mini-GWAC telescope network was fully operational.Due to the wide field of view and fast automatic follow-up capabilities of the mini-GWAC telescopes,they were adept to efficiently cover the sky localization areas of GW event candidates.In this paper,we present the mini-GWAC pipeline we have set up to respond to GW alerts and we report our optical follow-up observations of eight GW alerts detected during the O2 run.Our observations provided the largest coverage of the GW localization areas with a short latency made by any optical facility.We found tens of optical transient candidates in our images,but none of those could be securely associated with any confirmed black hole-black hole merger event.Based on this first experience and the near future technical improvements of our network system,we will be more competitive in detecting the optical counterparts from some GW events that will be identified during the upcoming O3 run,especially those emerging from binary neutron star mergers.

Hybrid fluid–particle modeling of shock-driven hydrodynamic instabilities in a plasma

Shock-driven hydrodynamic instabilities in a plasma usually lead to interfacial mixing and the generation of electromagnetic fields,which are nonequilibrium processes coupling kinetics with meso-and macroscopic dynamics.The understanding and modeling of these physical processes are very challenging tasks for single-fluid hydrodynamic codes.This work presents a new framework that incorporates both kinetics and hydrodynamics to simulate shock waves and hydrodynamic instabilities in high-density plasmas.In this hybrid code,ions are modeled using the standard particle-in-cell method together with a Monte Carlo description of collisions while electrons are modeled as a massless fluid,with the electron heat flux and fluid–particle energy exchange being considered in the electron pressure equation.In high-density plasmas,Maxwell’s equations are solved using Ohm’s law instead of Ampere’s law.This hybrid algorithm retains ion kinetic effects and their consequences for plasma interpenetration,shock wave propagation,and hydrodynamic instability.Furthermore,we investigate the shock-induced(or gravity-induced)turbulent mixing between a light and a heavy plasma,where hydrodynamic instabilities are initiated by a shock wave(or gravity).This study reveals that self-generated electromagnetic fields play a role in the formation of baroclinic vorticity along the interface and in late-time mixing of the plasmas.Our results confirm the ability of the proposed method to describe shock-driven hydrodynamic instabilities in a plasma,in particular,nonequilibrium processes that involve mixing and electromagnetic fields at the interface.

Photometric Calibration of the Lunar-based Ultraviolet Telescope for Its First Six Months of Operation on the Lunar Surface

We describe the photometric calibration of the Lunar-based Ultraviolet Telescope（LUT）, the first robotic astronomical telescope working on the lunar surface, for its first six months of operation on the lunar surface. Two spectral datasets（set A and B） from near-ultraviolet（NUV） to the optical band were constructed with 44 International Ultraviolet Explorer（IUE） standards, because of the LUT＇s relatively wide wavelength coverage. Set A was obtained by extrapolating the IUE NUV spectra（λ 〈 3200 ） to the optical band based upon the theoretical spectra of stellar atmosphere models. Set B was composed of theoretical spectra from 2000 to 8000 extracted from the same model grid. In total, seven standards have been observed in15 observational runs until May 2014. The calibration results show that the photometric performance of LUT is highly stable in its first six months of operation. The magnitude zero points obtained from the two spectral datasets are also consistent with each other, i.e., zp = 17.54 ± 0.09 mag（set A） and zp = 17.52 ± 0.07 mag（set B）.

NUV Star Catalog from the Lunar-based Ultraviolet Telescope Survey: First Release

We present a star catalog extracted from the Lunar-based Ultraviolet Telescope （LUT） survey program. LUT＇s observable sky area is a circular belt around the Moon＇s north pole, and the survey program covers a preferred area of about 2400 deg2 which includes a region of the Galactic plane. The data are processed with an automatic pipeline which copes with stray light contamination, artificial sources, cosmic rays, flat field calibration, photometry and so on. In the first release version, the catalog provides high confidence sources which have been cross-identified with the Tycho-2 catalog. All the sources have signalto-noise ratio larger than 5, and the corresponding magnitude limit is typically 14.4 mag, but can be as deep as -16 mag if stray light contamination is at the lowest level. A total of 86 467 stars are recorded in the catalog. The full catalog in electronic form is available online.

Separating the contributions of electric and magnetic fields in deflecting the probes in proton radiography with multiple proton energies

In proton radiography,degeneracy of electric and magnetic fields in deflecting the probe protons can prevent full interpretation of proton flux perturbations in the detection plane.In this paper,theoretical analyses and numerical simulations suggest that the contributions of the electric and magnetic fields can be separately obtained by analyzing the difference between the flux distributions of two discriminated proton energies in a single shot of proton radiography.To eliminate the influence of field evolution on the separation,a strategy is proposed in which slow field evolution is assumed or an approximate estimate of field growth is made.This could help achieve a clearer understanding of the radiographic process and allow further quantitative analysis.

Clinical experience of Professor Xie Jingri in the deficiency-cold of spleen and stomach type of complex peptic ulcer

Objective:To summarize Professor Xie's clinical experience in treating the deficiency cold of spleen and stomach type of complex peptic ulcer.Methods:through the observation of the curative effect of the patients with the deficiency cold of spleen and stomach type of complex peptic ulcer in the outpatient department of liver,spleen and stomach department of our hospital,the dialectical application and clinical experience of Professor Xie Jingri's self-made prescription in clinical practice were summarized.Results:Professor Xie Jingri's self-made prescription can effectively improve the clinical symptoms of patients with the deficiency cold of spleen and stomach type of complex peptic ulcer,and through individual syndrome differentiation and treatment,make the self-made prescription vary from person to person,clinical addition and subtraction,so as to further improve the clinical efficacy of patients.Conclusion:Professor Xie Jingri's self-made prescription is effective in treating complex peptic ulcer of spleen stomach deficiency cold type,which is worthy of further clinical application and promotion.

Review on the progress of treating gastric precancerous lesions with traditional Chinese medicine based on regulatory genes

In recent years,the incidence of Precancerous lesions of gastric cancer(PLGC)has gradually increased,and it is difficult to be cured and easy to recur.Traditional Chinese Medicine(TCM)emphasizes the prevention before the disease.The regulation of PLGC related tumor genes by Chinese medicine has become a research hotspot.This paper summarized PLGC related proto-oncogenes,tumor suppressor genes and apoptosis related genes,and discussed the mechanism of Chinese Medicine Therapy PLGC from the perspective of gene expression,providing new ideas and methods for clinical treatment of PLGC.

Advances in the treatment of peptic ulcer by acupoint application therapy

Acupoint application therapy is a convenient,effective and with few side effects traditional Chinese medicine external treatment method.It’s dual effects of drug absorption and acupoint stimulation show unique advantages in the clinical treatment of peptic ulcer(PU).This paper summarized its research progress in terms of its medication,acupoint selection and the synergistic application.It’s clear that acupoint application has a positive effect in the treatment of PU and it can better improve the clinical symptoms of epigastric pain in patients with PU,so as to provide new ideas for further exploration of its research direction and demonstration of its efficacy.

A demonstration of extracting the strength and wavelength of the magnetic field generated by the Weibel instability from proton radiography

The Weibel instability and the induced magnetic field are of great importance for both astrophysics and inertial confinement fusion.Because of the stochasticity of this magnetic field,its main wavelength and mean strength,which are key characteristics of the Weibel instability,are still unobtainable experimentally.In this paper,a theoretical model based on the autocorrelation tensor shows that in proton radiography of the Weibel-instability-induced magnetic field,the proton flux density on the detection plane can be related to the energy spectrum of the magnetic field.It allows us to extract the main wavelength and mean strength of the two-dimensionally isotropic and stochastic magnetic field directly from proton radiography for the first time.Numerical calculations are conducted to verify our theory and show good consistency between pre-set values and the results extracted from proton radiography.

Review of the current status of fast ignition research atthe IAPCM

We review the present status and future prospects of fast ignition(FI) research of the theoretical group at the IAPCM(Institute of Applied Physics and Computational Mathematics, Beijing) as a part of the inertial confinement fusion project. Since the approval of the FI project at the IAPCM, we have devoted our efforts to improving the integrated codes for FI and designing advanced targets together with the experimental group. Recent FI experiments [K. U. Akli et al., Phys. Rev. E 86, 065402(2012)] showed that the petawatt laser beam energy was not efficiently converted into the compressed core because of the beam divergence of relativistic electron beams. The coupling efficiency can be improved in three ways:(1) using a cone–wire-in-shell advanced target to enhance the transport efficiency,(2) using external magnetic fields to collimate fast electrons, and(3) reducing the prepulse level of the petawatt laser beam. The integrated codes for FI, named ICFI, including a radiation hydrodynamic code, a particle-in-cell(PIC) simulation code,and a hybrid fluid–PIC code, have been developed to design this advanced target at the IAPCM. The Shenguang-II upgraded laser facility has been constructed for FI research; it consists of eight beams(in total 24 kJ/3ω, 3 ns) for implosion compression, and a heating laser beam(0.5–1 kJ, 3–5 ps) for generating the relativistic electron beam. A fully integrated FI experiment is scheduled for the 2014 project.