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相关论文: Gd Transition Probabilities and Abundances

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We derive a new abundance for vanadium in the bright, mildly metal-poor red giant Arcturus. This star has an excellent high-resolution spectral atlas and well-understood atmospheric parameters, and it displays a rich set of neutral vanadium…

太阳与恒星天体物理 · 物理学 2018-02-21 M. P. Wood , C. Sneden , J. E. Lawler , E. A. Den Hartog , J. J. Cowan , G. Nave

To test the predictive power of ab initio nuclear structure theory, the lifetime of the second 2+ state in neutron-rich 20O, tau(2+_2 ) = 150(+80-30) fs, and an estimate for the lifetime of the second 2+ state in 16C have been obtained, for…

Plausible ratios of deuterium to hydrogen D/H as a function of metallicity, time, and redshift are investigated. Guided by the heavy element abundance patterns observed locally in Galactic dwarf stars and at large redshift in quasi-stellar…

天体物理学 · 物理学 2009-05-29 F. X. Timmes , J. W. Truran , J. T. Lauroesch , D. G. York

The Gaia spacecraft of the European Space Agency (ESA) has been securing observations of solar system objects (SSOs) since the beginning of its operations. Gaia Data Release 2 (DR2) contains the observations of a selected sample of 14,099…

地球与行星天体物理 · 物理学 2018-08-15 Gaia Collaboration , F. Spoto , P. Tanga , F. Mignard , J. Berthier , B. Carry , A. Cellino

Coalescence of binary neutron star give rise to electromagnetic emission, kilonova, powered by radioactive decays of r-process nuclei. Observations of kilonova associated with GW170817 provided unique opportunity to study the heavy element…

太阳与恒星天体物理 · 物理学 2019-02-13 Gediminas Gaigalas , Daiji Kato , Pavel Rynkun , Laima Radziute , Masaomi Tanaka

Energy levels, radiative rates and lifetimes are calculated among the lowest 98 levels of the n <= 4 configurations of Be-like Al X. The GRASP (General-purpose Relativistic Atomic Structure Package) is adopted and data are provided for all…

太阳与恒星天体物理 · 物理学 2015-06-18 K. M. Aggarwal , F. P. Keenan

Lifetimes of $2^+_1$ and $4^+_1$ states, as well as some negative-parity and non-yrast states, in $^{188-200}$Hg were measured using $\gamma-\gamma$ electronic fast timing techniques with the LaBr$_3$(Ce) detector array of the GRIFFIN…

The electric quadrupole transition from the first 2+ state to the ground 0+ state in 18C was studied through lifetime measurement by an upgraded recoil shadow method applied to inelastically scattered radioactive 18C nuclei. The measured…

The recent parameterisation by the GSP-spec module of Gaia/RVS spectra has produced an homogeneous catalogue of about 174,000 AGB stars. Among the 13 chemical elements presented in this catalogue, the abundance of 2 of them (Ce and Nd) have…

太阳与恒星天体物理 · 物理学 2024-01-02 G. Contursi , P. de Laverny , A. Recio-Blanco , P. A. Palicio , C. Abia

The damped Lyman alpha systems seen in the spectra of high redshift QSOs offer the means to determine element abundances in galaxies observed while still at an early stage of evolution. Such measurements, which have only recently come…

天体物理学 · 物理学 2016-08-30 Max Pettini , Keith Lipman , Richard W. Hunstead

We use our new, flux-calibrated stellar population model of absorption-line indices to derive ages, metallicities, and various element abundance ratios from integrated light spectroscopy of galactic globular clusters. The ages agree well…

宇宙学与河外天体物理 · 物理学 2015-05-20 Daniel Thomas , Jonas Johansson , Claudia Maraston

Although variations in elemental abundance ratios in the Milky Way Galaxy certainly exist, details remain uncertain, particularly in the inner Galaxy, where stars and H II regions in the Galactic plane are obscured optically. In this paper…

天体物理学 · 物理学 2009-11-10 Janet P. Simpson , Robert H. Rubin , Sean W. J. Colgan , Edwin F. Erickson , Michael R. Haas

Ultra diffuse galaxies are a population of extended galaxies but with relatively low luminosities. The origin of these objects remains unclear, largely due to the observational challenges of the low surface brightness Universe. We present…

We present a nearly complete rapid neutron-capture process (r-process) chemical inventory of the metal-poor ([Fe/H] = -1.46 +/- 0.10) r-process-enhanced ([Eu/Fe] = +1.32 +/- 0.08) halo star HD 222925. This abundance set is the most complete…

Updated evolutionary and pulsational model predictions are combined in order to interpret the properties of Galactic Classical Cepheids in the Gaia Data Release 2. In particular, the location of the instability strip boundaries and the…

太阳与恒星天体物理 · 物理学 2020-07-08 Giulia De Somma , Marcella Marconi , Santi Cassisi , Vincenzo Ripepi , Silvio Leccia , Roberto Molinaro , Ilaria Musella

The abundance of holmium (Z = 67) in the Sun remains uncertain. The photospheric abundance, based on lines of Ho II, has been reported as +0.26 +/- 0.16 (on the usual scale where log(H) = 12.00), while the meteoretic value is +0.51 +/-…

天体物理学 · 物理学 2015-06-24 Donald J. Bord , Charles R. Cowley

Experimental evidence indicating the beneficial impact of a phosphorous diffusion gettering (PDG) in the reduction of trapping centers is shown, as observed by means of inductively coupled photoconductance (PC) decay and lifetime…

Context. The pursuit of more realistic spectroscopic modelling and consistent abundances has led us to begin a new series of papers designed to improve current solar and stellar abundances of various atomic species. To achieve this, we have…

太阳与恒星天体物理 · 物理学 2020-02-12 A. J. Gallagher , M. Bergemann , R. Collet , B. Plez , J. Leenaarts , M. Carlsson , S. A. Yakovleva , A. K Belyaev

The decomposition of the Solar system abundances of heavy isotopes into their s- and r- components plays a key role in our understanding of the corresponding nuclear processes and the physics and evolution of their astrophysical sites. We…

星系天体物理 · 物理学 2020-01-08 N. Prantzos , C. Abia , S. Cristallo , M. Limongi , A. Chieffi

The second Gaia data release (DR2), contains very precise astrometric and photometric properties for more than one billion sources, astrophysical parameters for dozens of millions, radial velocities for millions, variability information for…