New planetary nebulae in the outskirts of the Andromeda Galaxy discovered with the Guoshoujing Telescope (LAMOST)

Planetary nebulae （PNe） are good tracers of the stellar populations, chemical composition and dynamics of their host galaxies. This paper reports the discovery of new PNe in the outskirts of the Andromeda Galaxy （M31） with the Guoshoujing Telescope （GSJT, formerly named the Large Sky Area Multi-Object Fiber Spectroscopic Telescope-LAMOST） during its early commissioning phase. In total, 36 candidates selected from SDSS photometry are confirmed in terms of their PN nature, including 17 new discoveries and another 19 previously known emission line objects. Their positions, spectra, radial velocities and m5007 magnitudes are presented. We discuss the potential for detecting more PNe in M 31 with GSJT＇s multi-object spectroscopy and the related applications in studies of the dynamics and chemistry of M 31 and its assemblage history.

Planetary nebulae in the circumnuclear region of M31:a spectroscopic sample

Planetary nebulae(PNe) are an important tool for studying the dynamics and chemical evolution of galaxies in the Local Universe, given their characteristic bright emission line spectra. The Andromeda Galaxy(M31) provides a unique laboratory for studying PNe in the circumnuclear region,thanks to its proximity and almost uniformly low line-of-sight extinction that ensures observations with high resolution and sensitivity. Using the WIYN/Hydra multi-fiber spectrograph, we have obtained optical(4119–6882 A?) spectra of 77 PN candidates selected from Hubble Space Telescope narrow-band imaging, which are located within the central ~500 pc region of M31. Among these candidates, 49(64%) are spectroscopically observed for the first time. The spectra of 300 previously known PNe and H Ⅱ regions, which primarily reside in the disk, are also taken for comparison. All 77 circumnuclear PN candidates exhibit prominent emission lines, including [O Ⅲ] λ5007, [N Ⅱ] λ6583, Hα and Hβ,strongly suggesting that they are genuine PNe. We measured the line fluxes, radial velocities and line widths for all objects, and found that the radial velocities of the circumnuclear PNe generally trace rotation of the inner bulge. We also estimated a dynamical mass of ~6.4±0.5×10~9 M_⊙ enclosed within an effective galactocentric radius of 340 pc, which is compatible with the previously estimated total stellar mass in this region.

M31中球状星团的双星族合成研究

采用双星族演化合成模型对M31(仙女座大星云)中24个球状星团进行了研究.结果表明:这些球状星团的年龄都大于1.5Gyr,有83.3%以上的球状星团的年龄在4.0Gyr以上;而金属丰度都小于0.0240,有87.5%的星团的金属丰度小于等于0.0090,62.5%的星团的金属丰度小于等于0.0040.整个样本球状星团的平均年龄和平均金属丰度分别为8.4Gyr和0.0067,总体上该样本球状星团的年龄较老,贫金属丰度,这与目前球状星团主流研究结果一致.

A catalogue of Hα emission-line point sources in the vicinity fields of M31 and M33 from the LAMOST survey

We present a catalogue of 3305 Hα emission-line point sources observed with the Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST) in the vicinity fields of M31 and M33 during September 2011 and January 2016.The catalogue contains 1487 emission-line stars,532 emission-line nebulae including 377 likely planetary nebulae(PNe),83 H Ⅱ region candidates and 20 possible supernova remnants(SNRs) and 1286 unknown objects.Among them,24 PN candidates,19 H Ⅱ region candidates,10 SNR candidates and one symbiotic star candidate are new discoveries.Radial velocities and fluxes estimated from the Hα line and those quantities of seven other major emission lines including Hβ,[O Ⅲ] A4959,[O Ⅲ] A5007,[N Ⅱ] A6548,[N Ⅱ] A6583,[S Ⅱ] A6717 and [S Ⅱ] A6731 lines of all the catalogued sources yielded from the LAMOST spectra are also presented in our catalogue.Our catalogue is an ideal starting point to study the chemistry properties and kinematics of M 31 and M 33.

Frequency Decay through Electromagnetic Radiation Absorption and Re-Emission by Inter-Galactic Dark Matter as an Alternate Explanation for the Hubble Constant

There is an alternate cause for the decay rate defined by Edwin Hubble’s Cosmological Constant Theory. It can be proposed because inward motion is observed in the local Galaxies||Star groups around the Milky Way. The recession velocity of Galaxies farther out of is reasoned entirely from the increasing redshift in the frequency. The smaller the image of observed Galaxy/Cluster objects, the greater the downward shift in frequency of all Electro-Magnetic signals [EM]. An alternate cause for that downward shift could be through the absorption and re-emission through matter, leading to the absorption of some fraction of the energy quanta. There is nowhere in our Local Universe that is both absolutely devoid of matter and the continual formation of objects of all scales. If redshift was because of space expansion, it would increase the distance that signal had to travel. So a signal from GN-z11 stellar structure at 13.4 billion light years [LY] would take 13.4 billion years to travel. Assuming 13.8 billion years since the Big Bang would mean GN-z11 object travelled 13.4 billion LY in 400 million years. A current value for the Hubble constant is: H0=(67.8 ± 0.77) km s -1 Mpc -1 a frequency is shift of 67.8/c over a single Mpc. An alternate expression would be a shift factor 2.261560E-5 over a distance of 3.08567E22 m or a redshift of 7.32923E-28 over a metre because of passage through a medium. Dark matter is a currently accepted phenomenon. It is proposed that properties include redshift’s all normal matters that are put upon EM||Boson signals at the fraction stated above. The signal reduction|| frequency distortion happens at a quantum level for each occurrence, and so is not detectable until passage through millions of LY of Dark Matter. Support for this alternate supposition is reasoned from the fact that the M31 Galaxy and the NGC 300 Galaxy are at distances inconsistent with their Hubble recession velocity.