Results 61 to 70 of about 410,681 (239)
Advanced Engineering Materials, EarlyView., 2023 A novel method for tracking structural changes in gels using widely accessible microcomputed tomography is presented and validated for various hydro‐, alco‐, and aerogels. The core idea of the method is to track positions of micrometer‐sized tracer particles entrapped in the gel and relate them to the density of the gel network.
Anja Hajnal +3 more
wiley +1 more source
Observations of surface-brightness fluctuations in Virgo
The Astronomical Journal, 1990 VRI photometric observations of surface-brightness fluctuation in 13 Virgo Cluster galaxies, M32, and NGC 3379, obtained using an 800 x 800 CCD array on the 4-m telescope at KPNO during March 1989, are reported. The data-reduction techniques are described in detail, and the results are presented in tables and graphs.
Gerard A. Luppino +2 more
openaire +2 more sources
Measuring Distances to Low-luminosity Galaxies Using Surface Brightness Fluctuations [PDF]
The Astrophysical Journal, 2021 Abstract We present an in-depth study of surface brightness fluctuations (SBFs) in low-luminosity stellar systems. Using the MIST models, we compute theoretical predictions for absolute SBF magnitudes in the LSST, HST ACS/WFC, and proposed Roman Space Telescope filter systems.
Johnny P. Greco +4 more
openaire +3 more sources
Detection of CFIRB with AKARI/FIS Deep Observations [PDF]
, 2007 The Cosmic Far-Infrared Background (CFIRB) contains information about the number and distribution of contributing sources and thus gives us an important key to understand the evolution of galaxies.
Chris P. Pearson +33 more
core +1 more source
Surface brightness fluctuations as primary and secondary distance indicators [PDF]
Astrophysics and Space Science, 2012 The surface brightness fluctuations (SBF) method measures the variance in a galaxy's light distribution arising from fluctuations in the numbers and luminosities of individual stars per resolution element. Once calibrated for stellar population effects, SBF measurements with HST provide distances to early-type galaxies with unrivaled precision. Optical
openaire +5 more sources
EFFECTS OF α-ELEMENT ENHANCEMENT AND THE THERMALLY PULSING-ASYMPTOTIC GIANT BRANCH ON SURFACE BRIGHTNESS FLUCTUATION MAGNITUDES AND BROADBAND COLORS [PDF]
, 2009 We investigate the effects of α-element enhancement and the thermally pulsing-asymptotic giant branch (TP-AGB) stars on the surface brightness fluctuation (SBF) magnitudes and broadband colors of simple stellar populations and compare to the empirical ...
Hyun-Chul Lee, G. Worthey, J. Blakeslee
semanticscholar +1 more source
On the origin of the optical and near-infrared extragalactic background light [PDF]
, 2020 In optical and near-infrared background light, excess brightness and fluctuation over the known backgrounds have been reported. To delineate their origin, a fluctuation analysis of the deepest optical images was performed, leading to the detection of a flat fluctuation down to 0.2 arcsec, which is much larger than that expected for galaxies.
arxiv +1 more source
Chandra measurements of gas homogeneity and turbulence at intermediate radii in the Perseus Cluster [PDF]
, 2022 We present a Chandra study of surface brightness fluctuations in the diffuse intracluster medium of the Perseus Cluster. Our study utilizes deep, archival imaging of the cluster core as well as a new mosaic of 29 short 5 ks observations extending in 8 different directions out to radii of r_500 ~ 2.2r_2500.
arxiv +1 more source
The surface brightness fluctuations and globular cluster populations of M87 and its companions [PDF]
The Astrophysical Journal, 1997 Using the surface brightness fluctuations in HST WFPC-2 images, we determine that M87, NGC 4486B, and NGC 4478 are all at a distance of ~16 Mpc, while NGC 4476 lies in the background at ~21 Mpc. We also examine the globular clusters of M87 using archived HST fields.
Eric H. Neilsen +2 more
openaire +6 more sources
应用气象学报Based on FY-4A geostationary satellite multi-channel data, mesoscale convective systems (MCSs) during three downhill processes of convection strengthening (1 July 2021, 12 June 2022 and 4 August 2022) in Beijing are identified by temperature threshold ...
Yang Yiya +5 more
doaj +1 more source