Search Publications
Missions
Journals
Publication Years
A Very Compact Dense Galaxy Overdensity with δ ≃ 130 Identified at z ∼ 8: Implications for Early Protocluster and Cluster Core Formation
Ouchi, Masami; Harikane, Yuichi; Ishigaki, Masafumi
We report the first identification of a compact dense galaxy overdensity at z∼ 8 called A2744z8OD. A2744z8OD consists of eight Y-dropout galaxies behind Abell 2744 that were originally pinpointed by Hubble Frontier Fields studies. However, so far, no studies have derived the basic physical quantities of structure formation or made comparisons with…
Galaxy clustering, CMB and supernova data constraints on ϕCDM model with massive neutrinos
Xu, Lixin; Chen, Yun
We investigate a scalar field dark energy model (i.e., ϕCDM model) with massive neutrinos, where the scalar field possesses an inverse power-law potential, i.e., V (ϕ) ∝ϕ-α (α > 0). We find that the sum of neutrino masses Σmν has significant impacts on the CMB temperature power spectrum and on the matter power spectrum. In…
Probing deep photospheric layers of the quiet Sun with high magnetic sensitivity
Franz, M.; Schmidt, W.; Solanki, S. K. +31 more
Context. Investigations of the magnetism of the quiet Sun are hindered by extremely weak polarization signals in Fraunhofer spectral lines. Photon noise, straylight, and the systematically different sensitivity of the Zeeman effect to longitudinal and transversal magnetic fields result in controversial results in terms of the strength and angular …
The evolution of the Sun's birth cluster and the search for the solar siblings with Gaia
Brown, A. G. A.; Antoja, T.; Portegies Zwart, S. +3 more
We use self-consistent numerical simulations of the evolution and disruption of the Sun's birth cluster in the Milky Way potential to investigate the present-day phase-space distribution of the Sun's siblings. The simulations include the gravitational N-body forces within the cluster and the effects of stellar evolution on the cluster population. …
Spatio-temporal Dynamics of Sources of Hard X-Ray Pulsations in Solar Flares
Zimovets, I. V.; Struminsky, A. B.; Kuznetsov, S. A. +1 more
We present a systematic analysis of the spatio-temporal evolution of sources of hard X-ray (HXR) pulsations in solar flares. We concentrate on disk flares whose impulsive phases are accompanied by a series of more than three successive peaks (pulsations) of HXR emission detected in the RHESSI 50 - 100 keV energy channel with a four-second time cad…
Disky Elliptical Galaxies and the Allegedly Over-massive Black Hole in the Compact “ES“ Galaxy NGC 1271
Ciambur, Bogdan C.; Graham, Alister W.; Savorgnan, Giulia A. D.
While spiral and lenticular galaxies have large-scale disks extending beyond their bulges, and most local early-type galaxies with 1010 < M */M ⊙ < 2 × 1011 contain a disk (e.g., ATLAS3D), the early-type galaxies do possess a range of disk sizes. The edge-on, intermediate-scale disk in t…
A Soft X-Ray Spectral Episode for the Clocked Burster, GS 1826-24 as Measured by Swift and NuStar
Harrison, F. A.; Stern, D.; Zhang, W. W. +12 more
We report on NuSTAR and Swift observations of a soft state of the neutron star low-mass X-ray binary GS 1826-24, commonly known as the “clocked” burster. The transition to the soft state was recorded in 2014 June through an increase of the 2-20 keV source intensity measured by MAXI, simultaneous with a decrease of the 15-50 keV intensity measured …
Scale-dependent Normalized Amplitude and Weak Spectral Anisotropy of Magnetic Field Fluctuations in the Solar Wind Turbulence
He, Jiansen; Wang, Xin; Wang, Linghua +2 more
Turbulence in the solar wind was recently reported to be anisotropic, with the average power spectral index close to -2 when sampling parallel to the local mean magnetic field B0 and close to -5/3 when sampling perpendicular to the local B0. This result was widely considered to be observational evidence for the critical balan…
Multiwavelength study of the flaring activity of Sagittarius A in 2014 February-April
Grosso, N.; Porquet, D.; Eckart, A. +8 more
Context. The supermassive black hole named Sgr A* is located at the dynamical center of the Milky Way. This closest supermassive black hole is known to have a luminosity several orders of magnitude lower than the Eddington luminosity. Flares coming from the Sgr A* environment can be observed in infrared, X-ray, and submillimeter wavelengths, but t…
A Herschel View of Protoplanetary Disks in the σ Ori Cluster
Calvet, Nuria; Briceño, César; Ali, Babar +6 more
We present new Herschel observations using the Photodetector Array Camera and Spectrometer of 32 T Tauri stars in the young (∼3 Myr) σ Ori cluster. Most of our objects are K and M stars with large excesses at 24 µm. We used irradiated accretion disk models of D’Alessio et al. to compare their spectral energy distributions with our observatio…