A few alpha-poor stars that show severe departures (over 0.4 dex deficiency in alpha-element abundance) from the general enhanced alpha-element chemical abundance trends of the halo have been discovered in recent years, such as BD +80°245, G4-36 and CS 22966-043. These ratios suggest a different chemical enrichment history for these stars than for the majority of the halo. Similarly low-alpha abundance patterns are also seen in the Sagittarius dSph galaxy. We present a method for searching of extremely alpha-poor stars from low-resolution stellar spectra of LAMOST pilot survey and attempt to create a large sample of these particular Galactic halo stars.

We map the stellar distribution on Hess diagram in the Anti-Center roughly in the boxes 130<l<230, −30<b<−10 and 10<b<30. There are ‘extra components’ associated with the anti-center structures of figure 1 of Newberg et al. (2002). The turnoff point of the structure in the North sky is at 16m.5 and the turnoff point in the South is at 17m.5. In our work, these structures can be found in all of the longitude in our box that can't be explained by standard thin or thick disk models. The distance of the North structure is about 2 kpc (we call it the North near structure) and the galactic height is about 0.7 kpc, the distance of the South structure is about 4 – 6 kpc (we call it the South middle structure). The Vgsr distribution of stars selected along the North near structure has a kinematic distribution similar to that of thick disk stars. But the metallicities of these stars are quite similar to the metallicity distribution of thin disk stars. We try to explain these structures with wave structure of the Galactic plane.

We obtained the chemical abundances of more than 20 Barium (Ba) stars by analysing high resolution echelle spectra. They show obvious overabundances of neutron capture process elements, such as Y, Zr, Ba, La and Eu. Their abundance pattern can be explained by binary accretion through stellar wind, where the Ba stars have accreted the ejecta from the companion stars which were in AGB stages at that time and now evolve as white dwarfs.

We first introduce the primary target allocation requirements and restrictions for the parallel control multiple fiber system, which is used in the LAMOST spectroscopic survey. The fiber positioner anti-collision model is imported. Then several target allocation methods and features are discussed in detail, including a network flow algorithm, high priority for fiber unit holding less target number, target allocation algorithm for groups, target allocation method for add-ons and target reallocation. Their virtues and weaknesses are analyzed for various kinds of scientific research situations. Furthermore an optimization concept using the Simulate Anneal Arithmetic (SAA) is developed to improve the fiber utilizing efficiency.

The Scandium abundances for 85 metal-poor stars are presented. Our result shows that NLTE corrections for Sc II lines are small (−0.04 to +0.06 dex). The abundance trends in stars of different populations are discussed.

We present chromospheric activities of late-type stars based on stellar spectrum survey of LAMOST (also called GuoShouJing telescope) in 2010-2013. Using the equivalent widths of the Hα line (larger than 1 Å), we have found 6391 active stars from 99741 M stars.

Sample contains 15 019 narrow emission-line galaxies, i.e. Seyferts, LINERs, composites and star-forming galaxies, from SDSS DR7 for systematically studying differences between different classes. We report two clear sequences of electron temperature (Te) and density (ne): Te-LINER ≳ Te-composite > Te-Seyfert > Te-star-forming and ne-Seyfert ≳ ne-LINER > ne-composite > ne-star-forming. General transitions of ne and Te from central regions to disks are quantitatively confirmed.

Three wide binary candidates that have been identified in the Large sky Area Multi-Object Spectroscopic Telescope (LAMOST) pilot survey data are presented. All three consist of main sequence stars of relatively late spectral type.

Since the Moon is the only natural satellite of the Earth, the research on the formation of the Moon can not only find out the formation mechanism of the satellites of Solar System planets but also reveal the evolution law of galaxies in the universe. Hence many hypotheses have been proposed for the Moon's formation, including fission,capture,condensation,and impact event hypothesis, but they all have problems. Recently, the author of this abstract discovered the formation mechanism of the Moon, which can be called “evolution theory”, and described as follows: During some violent volcanic eruptions of the Earth, some rock debris such as pumice through deep rock hole could achieve a velocity no less than the first cosmic velocity (7.9 km/s) to enter an orbit around the Earth, one of the biggest debris is the young Moon.

The orbit of the young Moon might be much closer to the Earth than it is today. There were a lot of ejecta from the Earth in the space. Hence, the Moon has merged these ejecta to become larger and larger, and farther and farther away from the Earth.This can be proved as follows: When the Moon moved around the Earth normally, the centrifugal force produced by the Moon's rotation around the Earth and the Earth's gravitation pull on the Moon had the same size. Let M be the mass of the Earth, m1 be the mass of the Moon, rm be the radius of the Moon, r be the centroid distance between the Earth and the Moon, v be the tangential velocity of the Moon around the Earth, then Gm1M/r2=m1v2/r, therefore $v=\sqrt{GM/r}$. Near the orbit of the Moon, there were also many smaller prograde planetesimals moving around the Earth in circular orbits of radius rx(r–rm<rx<r) with velocity vx. Since $v_x=\sqrt{GM/r_x}>\sqrt{GM/r}$, which implies vx > v, these planetesimals would finally catch and merge with the Moon.Especially,if a planetesimals was large enough, it would impact the Moon forcefully, making the Moon's velocity increase to a larger value v2. Then m1v22/r>m1v2/r=Gm1M/r2, therefore the Moon moved a reasonable distance away from the Earth.

The early orbit of the Moon was much closer to the Earth's atmosphere than it is now, so the Moon had absorbed much water vapor from the atmosphere to form lunar maria. Due to the constant erosion of water,a series of volcanic eruptions occurred at the bottom of lunar maria.Violent eruption could also change the orbit of the Moon around the Earth. Since most maria are on the near-side visible from Earth, so many violent volcanic eruptions at the bottom of these lunar maria could push the moon away from the Earth. This can be proved as follows: Let M be the mass of the Earth, m1 be the mass of the Moon left by the volcanic eruption, m2 be the total mass of erupted matter, m0(=m1+m2) be the total mass of the Moon before the eruption, v be the tangential velocity of the Moon around the Earth, r0 and r1 be the centroid distance between the Earth and the Moon before or after the eruption respectively; since the volcano ejected many substances toward the Earth, r1 > r0. Before the eruption, the centrifugal force produced by the Moon's rotation around the Earth and the Earth's gravitation pull on the Moon had the same size, therefore Gm0M/r02=m0v2/r0, which implies GM/r02=v2/r0. After the eruption,if the Moon hadn't changed its orbit then its velocity around the Earth was still v, so Gm1M/r12=(Gm1M/r02) (r02/r12)=(m1v2/r0) (r02/r12) =(m1v2/r1) (r0/r1)<(m1v2/r1), adding the continuous giant reaction force produced by volcanic eruption, the join force could push the Moon away from the Earth, even to an orbit where the water vapor evaporated from the Moon would be attracted back to the Earth,leaving dry lunar maria.