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Do protostellar fountains shape the regional core mass function?
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作者 Jin-Zeng Li Claudio Carlos Mallamaci +3 位作者 Ricardo César Podest Eloy Actis Vicente Ya-Fang Huang Ana Maria Pacheco 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2013年第6期719-728,共10页
The emerging massive binary system associated with AFGL 961 signifies the latest generation of massive star and cluster formation in the Rosette Molecular Complex. We present the detection of a compact cluster of dust... The emerging massive binary system associated with AFGL 961 signifies the latest generation of massive star and cluster formation in the Rosette Molecular Complex. We present the detection of a compact cluster of dusty cores toward the AFGL 961 region based on continuum imaging at 1.3 mm by the Submillimeter Array. The binary components of AFGL 961 are associated with the most intensive millime- ter emission cores or envelopes, confirming that they are indeed in an early stage of evolution. The other massive cores, however, are found to congregate in the close vicinity of the central high-mass protostellar binary. They have no apparent infrared counterparts and are, in particular, well aligned transverse to the bipolar molecular outflows originating from AFGL 961. This provides evidence for a likely triggered origin of the massive cores. All 40 individual cores with masses ranging between 0.6 and 15 Mo were detected above a 3 σ level of 3.6 mJy beam-1 (or 0.4 M⊙), based on which we derive a total core mass of 107 M⊙ in the AFGL 961 region. As compared to the stellar initial mass function, a shallow slope of 1.8 is, however, derived from the best fit to the mass spectrum of the millimeter cores with a prestellar and/or protostel- lar origin. The flatter core mass distribution in the AFGL 961 region is attributed here to dynamic perturbations from the massive molecular outflows that originated from the massive protostellar binary, which may have altered the otherwise more quiescent conditions of core or star formation, enhanced the formation of more massive cores and, as a result, influenced the core mass distribution in its close vicinity. 展开更多
关键词 stars formation -- stars individual (AFGL 961) -- stars circumstellarmatter -- stars mass function
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Standard and Truncated Luminosity Functions for Stars in the Gaia Era
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作者 Lorenzo Zaninetti 《International Journal of Astronomy and Astrophysics》 2017年第4期255-272,共18页
The luminosity function (LF) for stars is here fitted by a Schechter function and by a Gamma probability density function. The dependence of the number of stars on the distance, both in the low and high luminosity reg... The luminosity function (LF) for stars is here fitted by a Schechter function and by a Gamma probability density function. The dependence of the number of stars on the distance, both in the low and high luminosity regions, requires the inclusion of a lower and upper boundary in the Schechter and Gamma LFs. Three astrophysical applications for stars are provided: deduction of the parameters at low distances, behavior of the average absolute magnitude with distance, and the location of the photometric maximum as a function of the selected flux. The use of the truncated LFs allows modeling the Malmquist bias. 展开更多
关键词 FUNDAMENTAL Parameters stars luminosity function mass function
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The galaxy luminosity function in the LAMOST Complete Spectroscopic Survey of Pointing Area at the Southern Galactic Cap
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作者 Pin-Song Zhao Hong Wu +13 位作者 Cong Kevin Xu Ming Yang Fan Yang Yi-Nan Zhu Man I Lam Jun-Jie Jin Hai-Long Yuan Hao-Tong Zhang Shi-Yin Shen Jian-Rong Shi A-Li Luo Xue-Bing Wu Yong-Heng Zhao Yi-Peng Jing 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第8期69-80,共12页
We present optical luminosity functions(LFs) of galaxies in the0.1 g,0.1 r,0.1 i bands, calculated using data in40 deg2 sky area of the LAMOST Complete Spectroscopic Survey of Pointing Area(LaCoSSPAr) in the Southern ... We present optical luminosity functions(LFs) of galaxies in the0.1 g,0.1 r,0.1 i bands, calculated using data in40 deg2 sky area of the LAMOST Complete Spectroscopic Survey of Pointing Area(LaCoSSPAr) in the Southern Galactic Cap. Redshifts for galaxies brighter than r = 18.1 were obtained mainly with LAMOST. In each band, LFs derived using both parametric and non-parametric maximum likelihood methods agree well with each other. In the0.1 r band, our fitting parameters of the Schechter function are φ*=(1.65 ± 0.36) × 10-2 h3 Mpc-3, M*=-20.69 ± 0.06 mag and α =-1.12 ± 0.08,which agree with previous studies. Separate LFs are also derived for emission line galaxies and absorption line galaxies. The LFs of absorption line galaxies show a dip at0.1 r 18.5 and can be fitted well by a double-Gaussian function, suggesting a bimodality in passive galaxies. 展开更多
关键词 galaxies:luminosity function mass function galaxies:statistics galaxies:distances and REDSHIFTS
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Long-period eclipsing binaries:towards the true mass-luminosity relation.I.the test sample,observations and data analysis
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作者 Alexei Yu.Kniazev Oleg Yu.Maikov +1 位作者 Ivan Yu.Katkov Leonid N.Berdnikov 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2020年第8期169-176,共8页
The mass-luminosity relation is a fundamental law of astrophysics.We have suggested that the currently used mass-luminosity relation is not correct for the M/M⊙>2.7 range of mass since it was created utilizing dou... The mass-luminosity relation is a fundamental law of astrophysics.We have suggested that the currently used mass-luminosity relation is not correct for the M/M⊙>2.7 range of mass since it was created utilizing double-lined eclipsing binaries,where the components are synchronized and consequently change each other's evolutionary path.To exclude this effect,we have started a project to study longperiod massive eclipsing binaries in order to construct radial velocity curves and determine masses for the components.We outline our project and present the selected test sample together with the first HRS/SALT spectral observations and the software package,FITTING BINARY STARS(FBS),that we developed for the analysis of our spectral data.As the first result,we present the radial velocity curves and best-fit orbital elements for the two components of the FP Car binary system from our test sample. 展开更多
关键词 stars:luminosity function mass function stars:binaries:spectroscopic
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Constraining Mass of M31 Combing Kinematics of Stars,Planetary Nebulae and Globular clusters
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作者 Sunshun Yuan Ling Zhu +2 位作者 Cheng Liu Han Qu Zhou Fan 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2022年第8期270-283,共14页
We construct a multiple-population discrete axisymmetric Jeans model for the Andromeda(M31)galaxy,considering three populations of kinematic tracers:48 supergiants and 721 planetary nebulae(PNe)in the bulge and disk r... We construct a multiple-population discrete axisymmetric Jeans model for the Andromeda(M31)galaxy,considering three populations of kinematic tracers:48 supergiants and 721 planetary nebulae(PNe)in the bulge and disk regions,554 globular clusters extending to~30 kpc,and halo stars extending to~150 kpc of the galaxy.The three populations of tracers are organized in the same gravitational potential,while each population is allowed to have its own spatial distribution,rotation,and internal velocity anisotropy.The gravitational potential is a combination of stellar mass and a generalized NFW dark matter halo.We created two sets of models,one with a cusped dark matter halo and one with a cored dark matter halo.Both the cusped and cored model fit kinematics of all the three populations well,but the cored model is not preferred due to a too high concentration compared to that predicted from cosmological simulations.With a cusped dark matter halo,we obtained total stellar mass of 1.0±0.1×10^(11)M_(☉),dark matter halo virial mass of M_(200)=7.0±0.9×10^(11)M_(☉),virial radius of r_(200)=184±4 kpc,and concentration of c=20±4.The mass of M31 we obtained is at the lower side of the allowed ranges in the literature and consistent with the previous results obtained from the HⅠrotation curve and PNe kinematics.Velocity dispersion profile of the outer stellar halo is important in constraining the total mass while it is still largely uncertain.Further proper motion of bright sources from Gaia or the Chinese Space Station Telescope might help on improving the data and lead to stronger constraints on the total mass of M31. 展开更多
关键词 Galaxy:kinematics and dynamics galaxies:luminosity function mass function Galaxy:evolution
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New Probability Distributions in Astrophysics: X. Truncation and Mass-Luminosity Relationship for the Frèchet Distribution
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作者 Lorenzo Zaninetti 《International Journal of Astronomy and Astrophysics》 2022年第4期347-362,共16页
The Frèchet distribution has aided the modelling of scientific data in many contexts. We demonstrate how it can be adapted to model astrophysical data. We analyze the truncated version of the Frèchet distrib... The Frèchet distribution has aided the modelling of scientific data in many contexts. We demonstrate how it can be adapted to model astrophysical data. We analyze the truncated version of the Frèchet distribution deriving the probability density function (PDF), the distribution function, the average value, the rth moment about the origin, the median, the random generation of values and the maximum likelihood estimator, which allows us to derive the two unknown parameters. This first PDF in the regular and truncated version is then applied to model the mass of the stars. A canonical transformation from the mass to the luminosity allows us to derive a new PDF, which is derived in its regular and truncated version. Finally, we apply this new PDF model on the distribution in luminosity of NGC 2362. 展开更多
关键词 stars: Normal stars: luminosity function mass function stars: Statistics
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New Probability Distributions in Astrophysics: XII. Truncation for the Gompertz Distribution
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作者 Lorenzo Zaninetti 《International Journal of Astronomy and Astrophysics》 2024年第2期101-119,共19页
Analytical functions which fit the probability distributions of stars and galaxies can provide insight into how these distributions originate. In order to introduce a truncated version of the Gompertz distribution, we... Analytical functions which fit the probability distributions of stars and galaxies can provide insight into how these distributions originate. In order to introduce a truncated version of the Gompertz distribution, we derive its probability density function, its distribution function, its average value, its second moment about the origin, its median, its random generation of values and a maximum likelihood estimator for its two unknown parameters. The astrophysical applications of the Gompertz distribution are the initial mass function for stars, the luminosity function for the galaxies of the Sloan Digital Sky Survey, the photometric maximum of galaxies visible in the GLADE+ catalog and a model for the mean absolute magnitude in the GLADE+ catalog as a function of the redshift. 展开更多
关键词 stars: Normal stars: luminosity function mass function stars: Statistics
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New Probability Distributions in Astrophysics: XIII. Truncation for the Benini Distribution
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作者 Lorenzo Zaninetti 《International Journal of Astronomy and Astrophysics》 2024年第3期203-219,共17页
In order to introduce a right truncated version of the Benini distribution, we derive its probability density function, its distribution function, its average value, its kth moment about the origin, its median, how to... In order to introduce a right truncated version of the Benini distribution, we derive its probability density function, its distribution function, its average value, its kth moment about the origin, its median, how to randomly generate its values, and the maximum likelihood estimator for its three unknown parameters. The astrophysical application of the Benini distribution and its right truncated version is to the initial mass function for stars. 展开更多
关键词 stars: Normal stars: luminosity function mass function stars: Statistics
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Neutron stars:a relativistic study
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作者 Mehedi Kalam Sk.Monowar Hossein Sajahan Molla 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第3期1-8,共8页
We study the inner structure of a neutron star from a theoretical point of view and the outcome results are compared with observed data. We propose a stiff equation of state relating pressure with matter density. From... We study the inner structure of a neutron star from a theoretical point of view and the outcome results are compared with observed data. We propose a stiff equation of state relating pressure with matter density. From our study we calculate mass(M),compactness(u) and surface redshift(Zs) for two binary millisecond pulsars,namely PSR J1614–2230 and PSR J1903+327,and four X-ray binaries,namely Cen X-3,SMC X-1,Vela X-1 and Her X-1,and compare them with recent observational data.Finally,we examine the stability for such a type of theoretical structure. 展开更多
关键词 stars neutron - stars mass function- equation of state
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The Effective Chiral Model of Quantum Hadrodynamics Applied to Nuclear Matter and Neutron Stars 被引量:1
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作者 Hiroshi Uechi 《Journal of Applied Mathematics and Physics》 2015年第2期114-123,共10页
We review theoretical relations between macroscopic properties of neutron stars and microscopic quantities of nuclear matter, such as consistency of hadronic nuclear models and observed masses of neutron stars. The re... We review theoretical relations between macroscopic properties of neutron stars and microscopic quantities of nuclear matter, such as consistency of hadronic nuclear models and observed masses of neutron stars. The relativistic hadronic field theory, quantum hadrodynamics (QHD), and mean-field approximations of the theory are applied to saturation properties of symmetric nuclear and neutron matter. The equivalence between mean-field approximations and Hartree approximation is emphasized in terms of renormalized effective masses and effective coupling constants of hadrons. This is important to prove that the direct application of mean-field (Hartree) approximation to nuclear and neutron matter is inadequate to examine physical observables. The equations of state (EOS), binding energies of nuclear matter, self-consistency of nuclear matter, are reviewed, and the result of chiral Hartree-Fock ?approximation is shown. Neutron stars and history of nuclear astrophysics, nuclear model and nuclear matter, possibility of hadron and hadron-quark neutron stars are briefly reviewed. The hadronic models are very useful and practical for understanding astrophysical phenomena, nuclear matter and radiation phenomena of nuclei. 展开更多
关键词 A Relativistic Field THEORY of Nuclei: Quantum Hadrodynamics (QHD) The Equivalence of MEAN-FIELD Approximations and HARTREE Approximation Density functional THEORY (DFT) Maximum massES of Neutron stars
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Analytical model of compact star in low-mass X-ray binary with de Sitter spacetime
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作者 Sajahan Molla Rabiul Islam +1 位作者 Md.Abdul Kayum Jafry Mehedi Kalam 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第2期125-132,共8页
In this article, we suggest a Sitter model in favor of compact stars in low-mass X-ray binaries.Here, we have considered the presence of a cosmological constant(on a small scale) to investigate the stellar structure. ... In this article, we suggest a Sitter model in favor of compact stars in low-mass X-ray binaries.Here, we have considered the presence of a cosmological constant(on a small scale) to investigate the stellar structure. We conclude that this approach is very suitable for the familiar physical model of compact stars in low-mass X-ray binaries. We calculate the probable radius, compactness(u) and surface redshift(Z_s) of six compact stars in low-mass X-ray binaries, namely Cyg X-2, V395 Carinae/2 S 0921–630, XTE J2123–058,X1822–371(V691 CrA), 4 U 1820–30 and GR Mus(XB 1254–690). We also offer a possible equation of state(EOS) for the stellar objects. 展开更多
关键词 stars:low-mass stars:mass function EQUATION of state
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A Reinvestigation of the Physical Properties of Pismis 3 based on 2MASS Photometry
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作者 Tadross A.L. 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2008年第3期362-368,共7页
As a continuation of a series of work, we aim to refine and re-determine the physical parameters of previously rarely or un-studied open star clusters with good quality CMDs using Near-IR JHK photometry. Here we prese... As a continuation of a series of work, we aim to refine and re-determine the physical parameters of previously rarely or un-studied open star clusters with good quality CMDs using Near-IR JHK photometry. Here we present a morphological analysis of the 2MASS database (the digital "Two Micron All Sky Survey") for the open cluster Pismis 3. Some of the physical parameters are estimated for the first time, and some others, re-determined. 展开更多
关键词 techniques photometric -- Galaxy open clusters and associations -- stars luminosity function -- stellar clusters INDIVIDUAL Pismis 3
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New Probability Distributions in Astrophysics: XI. Left Truncation for the Topp-Leone Distribution
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作者 Lorenzo Zaninetti 《International Journal of Astronomy and Astrophysics》 2023年第3期154-165,共12页
The Topp-Leone (T-L) distribution has aided the modeling of scientific data in many contexts. We demonstrate how it can be adapted to model astrophysical data. We analyse the left truncated version of the T-L distribu... The Topp-Leone (T-L) distribution has aided the modeling of scientific data in many contexts. We demonstrate how it can be adapted to model astrophysical data. We analyse the left truncated version of the T-L distribution, deriving its probability density function (PDF), distribution function, average value, rth moment about the origin, median, the random generation of its values, and its maximum likelihood estimator, which allows us to derive the two unknown parameters. The T-L distribution, in its regular and truncated versions, is then applied to model the initial mass function for the stars. A comparison is made with specific clusters and between proposed functions for the IMF. The Topp-Leone distribution can provide an excellent fit in some cases. 展开更多
关键词 stars: Normal stars: luminosity function mass function stars: Statistics
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演化的星族合成方法 被引量:6
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作者 孔旭 程福臻 《天文学进展》 CSCD 北大核心 2001年第3期375-386,共12页
演化的星族合成方法是在给定恒星形成率和初始质量函数的前提下,利用理论的恒星演化轨迹和恒星光谱库得到的组合特征(光谱,光度),拟合星系、星团等恒星复合天体的观测特征,给出其中星族组成的一种有效方法。对演化的星族合成方法... 演化的星族合成方法是在给定恒星形成率和初始质量函数的前提下,利用理论的恒星演化轨迹和恒星光谱库得到的组合特征(光谱,光度),拟合星系、星团等恒星复合天体的观测特征,给出其中星族组成的一种有效方法。对演化的星族合成方法在天体物理研究中的重要意义及其原理和算法以及影响演化星族合成方法结果的最主要的四个输入量:恒星演化轨迹、恒星光谱库、初始质量函数和恒星形成率进行了评述。 展开更多
关键词 恒星形成率 初始质量函数 星族合成 简单星族 拟合星系 星团 恒星光谱库
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疏散星团M67的研究 被引量:1
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作者 田凯平 赵君亮 +1 位作者 潘容士 何燕萍 《天文学报》 CSCD 北大核心 1992年第4期427-435,共9页
本文利用上海天文台40厘米天体照相仪所拍摄的4对底片,在疏散星团M67天区的1067颗恒星中重新确定了星团成员星.在这一工作的基础上进而对星团M67的半径、年龄、距离、赫罗图、光度函数、质量以及速度弥散度和分层效应等作一定深度的讨论... 本文利用上海天文台40厘米天体照相仪所拍摄的4对底片,在疏散星团M67天区的1067颗恒星中重新确定了星团成员星.在这一工作的基础上进而对星团M67的半径、年龄、距离、赫罗图、光度函数、质量以及速度弥散度和分层效应等作一定深度的讨论.M67的半径为8.6Pc,年龄5.0×10~9年,距离模数(V—M_v)_0=9.63±0.33,相应的距离为843~pc,团的光度质量为1055μ_⊙,位力质量为2750μ_⊙,分析表明M67恒星在空间和速度上都呈现一定程度的质量分层,但这种效应并不明显. 展开更多
关键词 银河星团 位力质量 分层
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Virgo星系团的光度函数和质量函数 被引量:1
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作者 束成钢 赵君亮 田凯平 《天体物理学报》 CSCD 1995年第2期109-117,共9页
本文对Virgo星系团中央6°天区内的成员星系作了光度函数和质量函数的研究。成员星系是以视向速度作为判据并合理地考虑了密度分布因素后确定的。研究表明,该天区全部成员星系的光度函数为Schechter型,而各类S星... 本文对Virgo星系团中央6°天区内的成员星系作了光度函数和质量函数的研究。成员星系是以视向速度作为判据并合理地考虑了密度分布因素后确定的。研究表明,该天区全部成员星系的光度函数为Schechter型,而各类S星系的光度函数则为Gauss型,且峰值位置按Sa→Sd序列向暗端移动,宽度亦逐渐变宽;Virgo团质量函数与恒星质量函数一样可以用指数形式来描述,文中还利用光度函数和质量函数对该团的形态和质量分层进行了讨论,并计算了该天区团的总光度。 展开更多
关键词 星系团 光度函数 质量函数
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太阳附近主序星的光度函数
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作者 杨廷高 束成钢 +2 位作者 傅承启 蒋栋荣 彭秋和 《天文学报》 CSCD 北大核心 1995年第1期21-29,共9页
本文作者利用近距星星表第三版(CNS3)初始星表分析研究了太阳附近主序星的光度函数,并与用近距星星表弟二版(CNS2)所得结果和由测光视差方法得到的光度函数进行了比较。结果表明,对于绝对目视星等亮于15.5等的恒星,... 本文作者利用近距星星表第三版(CNS3)初始星表分析研究了太阳附近主序星的光度函数,并与用近距星星表弟二版(CNS2)所得结果和由测光视差方法得到的光度函数进行了比较。结果表明,对于绝对目视星等亮于15.5等的恒星,由CNS3得到的光度函数可能更接近于真实情况。同时还给出了由CNS3得到的巨星(含亮巨星)和A、F、G、K、M型主序星的光度函数。 展开更多
关键词 恒星 主序星 光度函数 太阳附近 25PC
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球状星团系统的比频、金属度和质量谱 被引量:1
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作者 王家骥 《天文学进展》 CSCD 北大核心 2002年第1期74-83,共10页
评述了球状星团系统研究中的比频、金属度和质量谱三大问题,就目前的认识和存在的问题进行了讨论。指出不同星系球状星团比频之间的差别表明了需要有各种不同的球状星团形成模型;球状星团金属度的分布表明球状星团可能有三个形成时期... 评述了球状星团系统研究中的比频、金属度和质量谱三大问题,就目前的认识和存在的问题进行了讨论。指出不同星系球状星团比频之间的差别表明了需要有各种不同的球状星团形成模型;球状星团金属度的分布表明球状星团可能有三个形成时期,分别与三类形成模型对应;尽管对数正态初始质量谱的数值模拟初步结果与观测结果符合得更好,然而幂函数的初始质量谱在物理上能很好地与球状星团形成联系起来。 展开更多
关键词 球状星团 星系 丰度 质量函数 比频 金属度 质量谱
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New Probability Distributions in Astrophysics: VI. The Truncated Sujatha Distribution 被引量:2
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作者 Lorenzo Zaninetti 《International Journal of Astronomy and Astrophysics》 2021年第4期517-529,共13页
The truncated version of the two-parameter Sujatha distribution is analysed. In particular, its probability density function and distribution function are obtained. The results are applied to the initial mass function... The truncated version of the two-parameter Sujatha distribution is analysed. In particular, its probability density function and distribution function are obtained. The results are applied to the initial mass function for stars, to the luminosity function for galaxies, to the number of galaxies as a function of the redshift and to the average absolute magnitude of a galaxy as a function of its redshift. 展开更多
关键词 stars: mass function Galaxy Groups CLUSTERS SUPERCLUSTERS Large Scale Structure of the Universe COSMOLOGY
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Galaxy formation in the reionization epoch as hinted by WideField Camera 3 observations of the Hubble Ultra Deep Field
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作者 Hao-Jing Yan Rogier A. Windhorst +4 位作者 Nimish E Hathi Seth H. Cohen Russell E.Ryan Robert W. O'Connell Patrick J. McCarthy 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2010年第9期867-904,共38页
We present a large sample of candidate galaxies at z ≈ 7 - 10, selected in the Hubble Ultra Deep Field using the new observations of the Wide Field Camera 3 that was recently installed on the Hubble Space Telescope. ... We present a large sample of candidate galaxies at z ≈ 7 - 10, selected in the Hubble Ultra Deep Field using the new observations of the Wide Field Camera 3 that was recently installed on the Hubble Space Telescope. Our sample is composed of 20 z850-dropouts (four new discoveries), 15 Y105-dropouts (nine new discoveries) and 20 J125-dropouts (all new discoveries). The surface densities of the Z850-dropouts are close to what was predicted by earlier studies, however, those of the Y105- and J125-dropouts are quite unexpected. While no Y105- or J125-dropouts have been found at AB ≤ 28.0 mag, their surface densities seem to increase sharply at fainter levels. While some of these candidates seem to be close to foreground galaxies and thus could possibly be gravitationally lensed, the overall surface densities after excluding such cases are still much higher than what would be expected if the luminosity function does not evolve from z ~ 7 to 10. Motivated by such steep increases, we tentatively propose a set of Schechter function parameters to describe the luminosity functions at z ≈8 and 10. As compared to their counterpart at z ≈ 7, here L^* decreases by a factor of ~ 6.5 and Ф^* increases by a factor of 17-90. Although such parameters are not yet demanded by the existing observations, they are allowed and seem to agree with the data better than other alternatives. If these luminosity functions are still valid beyond our current detection limit, this would imply a sudden emergence of a large number of low-luminosity galaxies when looking back in time to z ≈ 10, which, while seemingly exotic, would naturally fit in the picture of the cosmic hydrogen reionization. These early galaxies could easily account for the ionizing photon budget required by the reionization, and they would imply that the global star formation rate density might start from a very high value at z ≈ 10, rapidly reach the minimum at z≈ 7, and start to rise again towards z ≈ 6. In this scenario, the majority of the stellar mass that the universe assembled through the reionization epoch seems still undetected by current observations at z ≈ 6. 展开更多
关键词 COSMOLOGY observations -- cosmology early universe -- galaxies evolution -- galaxies luminosity function mass function -- infrared GALAXIES
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