Search results for "Photometric"
showing 10 items of 60 documents
Stellar populations of galaxies in the ALHAMBRA survey up toz ∼ 1
2018
Aims. We aim at constraining the stellar population properties of quiescent galaxies. These properties reveal how these galaxies evolved and assembled since z similar to 1 up to the present time. Methods. Combining the ALHAMBRA multi-filter photo-spectra with the fitting code for spectral energy distribution MUFFIT (MUlti-Filter FITting), we built a complete catalogue of quiescent galaxies via the dust-corrected stellar mass vs. colour diagram. This catalogue includes stellar population properties, such as age, metallicity, extinction, stellar mass, and photometric redshift, retrieved from the analysis of composited populations based on two independent sets of simple stellar population (SSP…
FPI Based Hyperspectral Imager for the Complex Surfaces : Calibration, Illumination and Applications
2022
Hyperspectral imaging (HSI) applications for biomedical imaging and dermatological applications have been recently under research interest. Medical HSI applications are non-invasive methods with high spatial and spectral resolution. HS imaging can be used to delineate malignant tumours, detect invasions, and classify lesion types. Typical challenges of these applications relate to complex skin surfaces, leaving some skin areas unreachable. In this study, we introduce a novel spectral imaging concept and conduct a clinical pre-test, the findings of which can be used to develop the concept towards a clinical application. The SICSURFIS spectral imager concept combines a piezo-actuated Fabry–Pé…
Spectral characteristics of 5-hydroxymethylfurfural as a related substance in medicinal products containing glucose
2019
Objectives: To study 5-hydroxymethylfurfural (5-HMF) spectral characteristics aiming at their future application in analytical procedures and their validation for the determination of 5-HMF in liquid products containing glucose after sterilization.Method: Direct spectrophotometric method for the determination of 5-HMF using the molar absorption coefficient at the absorption maximum (284 nm).Results and discussion: aqueous 5-HMF solutions have strong absorption in the ultraviolet range below 310 nm and give two absorption maxima at wavelengths of 229–230 nm and 284 nm. An excellent linear relationship between absorbance and 5-HMF concentration was observed in the concentration range of 2.0–1…
ON THE CONCEPT OF THE ENHANCED FON CATALOG COMPILATION
2017
We suppose to compile the enhanced version of FON (Photographic Survey of the Northern Sky) catalog of stellar positions and B-magnitudes in the sky region from -20 to 90 degrees on declination. The photographic base of the project comprises about 5,700 plates obtained at three observatories of the former SU MAO NAS of Ukraine, Kitab observatoryof Uzbekistan and Gissar observatory of Tajikistan. The mean epoch of the catalog is around 1988. The expected limited stellar magnitude is 17.5m. More than 5,400 plates are processed to support the photometric part of the catalog. The plates were shot on the 1.2 m Schmidt telescope in Baldone, Latvia, in the U and V bands. Color data provide the pos…
The ALHAMBRA survey: B -band luminosity function of quiescent and star-forming galaxies at 0.2 ≤ z < 1 by PDF analysis
2016
[Aims]: Our goal is to study the evolution of the B-band luminosity function (LF) since z ∼ 1 using ALHAMBRA data. [Methods]: We used the photometric redshift and the I-band selection magnitude probability distribution functions (PDFs) of those ALHAMBRA galaxies with I ≤ 24 mag to compute the posterior LF. We statistically studied quiescent and star-forming galaxies using the template information encoded in the PDFs. The LF covariance matrix in redshift - magnitude - galaxy type space was computed, including the cosmic variance. That was estimated from the intrinsic dispersion of the LF measurements in the 48 ALHAMBRA sub-fields. The uncertainty due to the photometric redshift prior is also…
Euclid preparation. XII. Optimizing the photometric sample of the Euclid survey for galaxy clustering and galaxy-galaxy lensing analyses
2021
Pocino, A., et al. (Euclid Collaboration)
The ALHAMBRA survey: Bayesian photometric redshifts with 23 bands for 3 deg2
2014
A. Molino et al.
KOSMOS 2017 Peru Side Experiment: nutrients, phytoplankton abundances, enzyme rates, photophysiology
2022
This data was collected during an short-term incubation experiment in March 2017 that investigated the response of a surface plankton community to upwelling. This experiment was carried in the framework of the SFB754-funded KOSMOS mesocosm study that took place in La Punta, Callao, Peru between February-April 2017. A total of six different treatments were used to disentangle chemical and biological characteristics of deep water that influence surface plankton blooms: 2 different deep water sources with different nutrient concentrations; 3 treatments to distinguish the effects of inorganic nutrients, organic nutrients and deep water microbial populations. Measured variables include inorganic…
Euclid preparation: XI. Mean redshift determination from galaxy redshift probabilities for cosmic shear tomography
2021
Ilbert, O., et al. (Euclid Collaboration)
A photometric study of Be stars located in the seismology fields of COROT
2007
Context: In preparation for the COROT mission, an exhaustive photometric study of Be stars located in the seismology fields of the COROT mission has been performed. The very precise and long-time-spanned photometric observations gathered by the COROT satellite will give important clues of the origin of the Be phenomenon. Aims: The aim of this work is to find short-period variable Be stars located in the seismology fields of COROT and to study and characterise their pulsational properties. Methods: Light curves obtained at the Observatorio de Sierra Nevada together with data from Hipparcos and ASAS-3 of a total of 84 Be stars have been analysed in order to search for short-term variations. W…