scholarly journals The VVDS-SWIRE-GALEX-CFHTLS surveys: physical properties of galaxies at z below 1.2 from photometric data

2008 ◽  
Vol 491 (3) ◽  
pp. 713-730 ◽  
Author(s):  
C. J. Walcher ◽  
F. Lamareille ◽  
D. Vergani ◽  
S. Arnouts ◽  
V. Buat ◽  
...  
2020 ◽  
Author(s):  
Josef Hanus ◽  
Ondrej Pejcha ◽  
Ben Shappee

<p>The All-Sky Automated Survey for Supernovae (ASAS-SN) currently<br />operates 24 small-aperture telescopes distributed around the globe to<br />automatically survey the entire visible sky every night down to about<br />g~18 mag. Between 2013 and 2018, the survey used a V filter with<br />limiting magnitude V~17. Although primarily hunting for supernovae and<br />other transients, asteroids are common intruders in the ASAS-SN's<br />images. Here we present efforts to analyze the sparsely sampled V-band<br />photometry extracted from the ASAS-SN images for >10,000 asteroids<br />that get brighter than V~17 mag. The data span years 2013-2018 and<br />sample up to 7 consequent apparitions for each asteroid. We provide<span class="im"><br />details about the photometry extraction and calibration, photometry<br />accuracy, and various statistics such as the typical number of data<br />points per asteroid as a function of the brightness. Finally, we<br /></span> analyze the photometric data with the lightcurve inversion method and<br />derive rotation periods, spin axis directions, and shapes for a sample<span class="im"><br />of studied asteroids. We discuss the typical amount of data sufficient<br />for a successful shape model determination. We compare derived<br />physical properties with those available in the literature to<br /></span> illustrate the reliability of the ASAS-SN photometry.</p>


2021 ◽  
Vol 503 (2) ◽  
pp. 1599-1614
Author(s):  
Michael Poon ◽  
J J Zanazzi ◽  
Wei Zhu

ABSTRACT KH 15D is a system that consists of a young, eccentric binary, and a circumbinary disc that obscures the binary as the disc precesses. We develop a self-consistent model that provides a reasonable fit to the photometric variability that was observed in the KH 15D system over the past 60 yr. Our model suggests that the circumbinary disc has an inner edge rin ≲ 1 au, an outer edge rout ∼ a few au, and that the disc is misaligned relative to the stellar binary by ∼5–16°, with the inner edge more inclined than the outer edge. The difference between the inclinations (warp) and longitude of ascending nodes (twist) at the inner and outer edges of the disc are of order ∼10 and ∼15°, respectively. We also provide constraints on other properties of the disc, such as the precession period and surface density profile. Our work demonstrates the power of photometric data in constraining the physical properties of planet-forming circumbinary discs.


2019 ◽  
Vol 15 (S341) ◽  
pp. 129-133
Author(s):  
M. Boquien ◽  
D. Burgarella ◽  
Y. Roehlly ◽  
V. Buat ◽  
L. Ciesla ◽  
...  

AbstractPanchromatic modeling is one of the most powerful tools at our disposal to measure reliably the physical properties of galaxies across cosmic times. We present here an entirely new implementation in python of one such tool: CIGALE. Developed along three main design principles: simplicity, modularity, and efficiency, it has proven to be a versatile code that in addition to estimating the physical properties of galaxies (or regions within galaxies), can generate arbitrary sets of theoretical models or be used as a library to build other tools. Among its defining features, it is a truly panchromatic code ranging from the far-ultraviolet to the radio that takes into account numerous physical components (including active nuclei or synchrotron emission), that can fit non-photometric data, handle upper limits, determine photometric redshifts, and even build mock catalogs.


1976 ◽  
Vol 32 ◽  
pp. 365-377 ◽  
Author(s):  
B. Hauck
Keyword(s):  

The Ap stars are numerous - the photometric systems tool It would be very tedious to review in detail all that which is in the literature concerning the photometry of the Ap stars. In my opinion it is necessary to examine the problem of the photometric properties of the Ap stars by considering first of all the possibility of deriving some physical properties for the Ap stars, or of detecting new ones. My talk today is prepared in this spirit. The classification by means of photoelectric photometric systems is at the present time very well established for many systems, such as UBV, uvbyβ, Vilnius, Geneva and DDO systems. Details and methods of classification can be found in Golay (1974) or in the proceedings of the Albany Colloquium edited by Philip and Hayes (1975).


Author(s):  
Frederick A. Murphy ◽  
Alyne K. Harrison ◽  
Sylvia G. Whitfield

The bullet-shaped viruses are currently classified together on the basis of similarities in virion morphology and physical properties. Biologically and ecologically the member viruses are extremely diverse. In searching for further bases for making comparisons of these agents, the nature of host cell infection, both in vivo and in cultured cells, has been explored by thin-section electron microscopy.


Author(s):  
K.P.D. Lagerlof

Although most materials contain more than one phase, and thus are multiphase materials, the definition of composite materials is commonly used to describe those materials containing more than one phase deliberately added to obtain certain desired physical properties. Composite materials are often classified according to their application, i.e. structural composites and electronic composites, but may also be classified according to the type of compounds making up the composite, i.e. metal/ceramic, ceramic/ceramie and metal/semiconductor composites. For structural composites it is also common to refer to the type of structural reinforcement; whisker-reinforced, fiber-reinforced, or particulate reinforced composites [1-4].For all types of composite materials, it is of fundamental importance to understand the relationship between the microstructure and the observed physical properties, and it is therefore vital to properly characterize the microstructure. The interfaces separating the different phases comprising the composite are of particular interest to understand. In structural composites the interface is often the weakest part, where fracture will nucleate, and in electronic composites structural defects at or near the interface will affect the critical electronic properties.


Author(s):  
James Mark ◽  
Kia Ngai ◽  
William Graessley ◽  
Leo Mandelkern ◽  
Edward Samulski ◽  
...  
Keyword(s):  

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