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771. Algol-type binaries. VIII. DI Peg & AF Gem
ID:
ivo://CDS.VizieR/J/AJ/147/145
Title:
Algol-type binaries. VIII. DI Peg & AF Gem
Short Name:
J/AJ/147/145
Date:
21 Oct 2021
Publisher:
CDS
Description:
New extensive photometry for two triple binary stars, DI Peg and AF Gem, was performed from 2012 October to 2013 January, with two small telescopes at Xinglong station (XLs) of NAOC. From new multi-color observations and previously published ones in literature, the photometric models were (re)deduced using the updated Wilson-Devinney code. The results indicated that the low third lights exist in two classic Algol-type binaries, whose fill-out factors for the more massive components are f_p_=78.2(+/-0.4)% for DI Peg, and f_p_=69.0(+/-0.3)% for AF Gem, respectively. Through analyzing the O-C curves, the orbital periods for two binaries change in the complicated mode. The period of DI Peg possibly appears to show two light-time orbits, whose modulated periods are P_3_=54.6(+/-0.5)yr and P_4_=23.0(+/-0.6)yr, respectively. The inferred minimum masses for the inner and outer sub-stellar companions are M_in_=0.095M_{sun}_ and M_out_=0.170M_{sun}_, respectively. Therefore, DI Peg may be a quadruple star. The orbital period of AF Gem appears to show a continuous period decrease or a cyclic variation; the latter may be preferable. The cyclic oscillation, with a period of 120.3(+/-2.5)yr, may be attributed to the light-time effect due to the third body. This kind of additional companion may extract angular momentum from the central system, which may play a key role in the evolution of the binary.
772. Algol-type eclipsing binaries differential photometry
ID:
ivo://CDS.VizieR/J/A+A/405/231
Title:
Algol-type eclipsing binaries differential photometry
Short Name:
J/A+A/405/231
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a systematic search for pulsating components in Algol-type eclipsing binary systems. A total number of 14 eclipsing binaries with A-F spectral type primary components were observed for 22 nights. We confirmed small-amplitude oscillating features of a recently detected pulsator TW Dra, which has a pulsating period of 0.053-day and a semi-amplitude of about 5-mmag in B-passband. We discovered new pulsating components in two eclipsing binaries of RX Hya and AB Per. The primary component of RX Hya is pulsating with a dominant period of 0.052-day and a semi-amplitude of about 7-mmag. AB Per has also a pulsating component with a period of 0.196-day and a semi-amplitude of about 10-mmag in B-passband. We suggest that these two new pulsators are members of the newly introduced group of mass-accreting pulsating stars in semi-detached Algol-type eclipsing binary systems.
773. Algorithm for correcting CoRoT raw light curves
ID:
ivo://CDS.VizieR/J/A+A/522/A86
Title:
Algorithm for correcting CoRoT raw light curves
Short Name:
J/A+A/522/A86
Date:
21 Oct 2021
Publisher:
CDS
Description:
We introduce the CoRoT Detrend Algorithm (CDA) for detrending CoRoT stellar light curves. CDA has the capability to remove random jumps and systematic trends encountered in typical CoRoT data in a fully automatic fashion. Since huge jumps in flux can destroy the information content of a light curve, such an algorithm is essential. From a study of 1030 light curves in the CoRoT IRa01 field we developed three simple assumptions CDA is based upon. In this paper we describe analytically the algorithm and we provide some examples of how it works. We demonstrate its functionality of the algorithm in the cases of CoRoT0102702789, CoRoT0102874481, CoRoT0102741994 and CoRoT0102729260. Using CDA in the specific case of CoRoT0102729260 we detect a candidate exoplanet around the host star of spectral type G5, which remains undetected in the raw light curve; the estimated planetary parameters are Rp=6.27R_E_ and P=1.6986days.
774. ALHAMBRA fields type-I AGN with ELDAR
ID:
ivo://CDS.VizieR/J/MNRAS/472/2085
Title:
ALHAMBRA fields type-I AGN with ELDAR
Short Name:
J/MNRAS/472/2085
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present ELDAR, a new method that exploits the potential of medium- and narrow-band filter surveys to securely identify active galactic nuclei (AGN) and determine their redshifts. Our methodology improves on traditional approaches by looking for AGN emission lines expected to be identified against the continuum, thanks to the width of the filters. To assess its performance, we apply ELDAR to the data of the ALHAMBRA survey, which covered an effective area of 2.38deg^2^ with 20 contiguous medium-band optical filters down to F814W=24.5. Using two different configurations of ELDAR in which we require the detection of at least 2 and 3 emission lines, respectively, we extract two catalogues of type-I AGN. The first is composed of 585 sources (79% of them spectroscopically-unknown) down to F814W=22.5 at z_phot_>1, which corresponds to a surface density of 209 deg-2. In the second, the 494 selected sources (83% of them spectroscopically-unknown) reach F814W=23 at z_phot_>1.5, for a corresponding number density of 176deg^-2^. Then, using samples of spectroscopically-known AGN in the ALHAMBRA fields, for the two catalogues we estimate a completeness of 73% and 67%, and a redshift precision of 1.01% and 0.86% (with outliers fractions of 8.1% and 5.8%). At z>2, where our selection performs best, we reach 85% and 77% completeness and we find no contamination from galaxies.
775. ALHAMBRA Final Archive: F814W images
ID:
ivo://svo.cab/alhambra_siap_f814w
Title:
ALHAMBRA Final Archive: F814W images
Short Name:
ALHAMBRA_F814W
Date:
14 Mar 2019 08:14:29
Publisher:
Spanish Virtual Observatory
Description:
This data server provides access to the F814W images of the ALHAMBRA Final Archive. The ALHAMBRA (Advance Large Homogeneous Area Medium Band Redshift Astronomical) survey (Moles et al. 2008) has observed 8 different regions of the sky, including sections of the COSMOS, DEEP2, ELAIS, GOODS-N, SDSS and Groth fields using a new photometric system with 20 contiguous, non-overlapping, equal width (~ 300A) filters, covering the optical range (3500A-9700A), plus the standard broadband NIR J, H and Ks filters. The observations were carried out with the Calar Alto (CAHA) 3.5m telescope using the wide field, 0.25 deg2 FOV optical camera LAICA and the NIR instrument Omega-2000. The ALHAMBRA survey dataset represents a ~700hrs of total exposure time, gathered in between the 2005 and 2012.Further information on the project can be found at the ALHAMBRA web page.
776. ALHAMBRA Final Catalogue
ID:
ivo://svo.cab/alhambra
Title:
ALHAMBRA Final Catalogue
Short Name:
ALHAMBRA
Date:
03 Jun 2020 15:33:39
Publisher:
SVO CAB
Description:
This data server provides access to the ALHAMBRA Final Catalogue. The ALHAMBRA (Advance Large Homogeneous Area Medium Band Redshift Astronomical) survey (Moles et al. 2008) has observed 8 different regions of the sky, including sections of the COSMOS, DEEP2, ELAIS, GOODS-N, SDSS and Groth fields using a new photometric system with 20 contiguous, non-overlapping, equal width (~ 300A) filters, covering the optical range (3500A-9700A), plus the standard broadband NIR J, H and Ks filters. The observations were carried out with the Calar Alto (CAHA) 3.5m telescope using the wide field, 0.25 deg2 FOV optical camera LAICA and the NIR instrument Omega-2000. The ALHAMBRA survey dataset represents a ~700hrs of total exposure time, gathered in between the 2005 and 2012.Further information on the project can be found at the ALHAMBRA web page.
777. ALHAMBRA photometric system
ID:
ivo://CDS.VizieR/J/AJ/139/1242
Title:
ALHAMBRA photometric system
Short Name:
J/AJ/139/1242
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents the characterization of the optical range of the ALHAMBRA photometric system, a 20 contiguous, equal-width, medium-band CCD system with wavelength coverage from 3500{AA} to 9700{AA}. The photometric description of the system is done by presenting the full response curve as a product of the filters, CCD, and atmospheric transmission curves, and using some first- and second-order moments of this response function. We also introduce the set of standard stars that defines the system, formed by 31 classic spectrophotometric standard stars which have been used in the calibration of other known photometric systems, and 288 stars, flux calibrated homogeneously, from the Next Generation Spectral Library (NGSL). Based on the NGSL, we determine the transformation equations between Sloan Digital Sky Survey ugriz photometry and the ALHAMBRA photometric system, in order to establish some relations between both systems. Finally, we develop and discuss a strategy to calculate the photometric zero points of the different pointings in the ALHAMBRA project.
778. ALHAMBRA Survey
ID:
ivo://CDS.VizieR/J/MNRAS/441/2891
Title:
ALHAMBRA Survey
Short Name:
J/MNRAS/441/2891
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Advance Large Homogeneous Area Medium-Band Redshift Astronomical (ALHAMBRA) survey has observed eight different regions of the sky, including sections of the Cosmic Evolution Survey (COSMOS), DEEP2, European Large-Area Infrared Space Observatory Survey (ELAIS), Great Observatories Origins Deep Survey North (GOODS-N), Sloan Digital Sky Survey (SDSS) and Groth fields using a new photometric system with 20 optical, contiguous ~300{AA} filters plus the JHKs bands. The filter system is designed to optimize the effective photometric redshift depth of the survey, while having enough wavelength resolution for the identification of faint emission lines. The observations, carried out with the Calar Alto 3.5-m telescope using the wide-field optical camera Large Area Imager for Calar Alto (LAICA) and the near-infrared (NIR) instrument Omega-2000, represent a total of ~700h of on-target science images. Here we present multicolour point-spread function (PSF) corrected photometry and photometric redshifts for ~438000 galaxies, detected in synthetic F814W images. The catalogues are complete down to a magnitude I~24.5AB and cover an effective area of 2.79deg^2^. Photometric zero-points were calibrated using stellar transformation equations and refined internally, using a new technique based on the highly robust photometric redshifts measured for emission-line galaxies. We calculate Bayesian photometric redshifts with the Bayesian Photometric Redshift (bpz)2.0 code, obtaining a precision of {delta}z/(1+z_s_)=1 per cent for I<22.5 and {delta}z/(1+z_s_)=1.4 per cent for 22.5<I<24.5. The global n(z) distribution shows a mean redshift <z>=0.56 for I<22.5AB and <z>=0.86 for I<24.5AB. Given its depth and small cosmic variance, ALHAMBRA is a unique data set for galaxy evolution studies.
779. ALHAMBRA survey galaxy clusters and groups
ID:
ivo://CDS.VizieR/J/MNRAS/452/549
Title:
ALHAMBRA survey galaxy clusters and groups
Short Name:
J/MNRAS/452/549
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalogue of 348 galaxy clusters and groups with 0.2<z<1.2 selected in the 2.78deg^2^ Advanced Large, Homogeneous Area Medium Band Redshift Astronomical (ALHAMBRA) survey. The high precision of our photometric redshifts, close to 1 percent, and the wide spread of the seven ALHAMBRA pointings ensure that this catalogue has better mass sensitivity and is less affected by cosmic variance than comparable samples. The detection has been carried out with the Bayesian Cluster Finder, whose performance has been checked in ALHAMBRA-like light-cone mock catalogues. Great care has been taken to ensure that the observable properties of the mocks photometry accurately correspond to those of real catalogues. From our simulations, we expect to detect galaxy clusters and groups with both 70 percent completeness and purity down to dark matter halo masses of M_h_~3x10^13^M_{sun}_ for z<0.85. Cluster redshifts are expected to be recovered with ~0.6 percent precision for z<1. We also expect to measure cluster masses with sigma_Mh_|M*CL_~0.25-0.35dex precision down to ~3x10^13^M_{sun}_, masses which are 50 percent smaller than those reached by similar work. We have compared these detections with previous optical, spectroscopic and X-rays work, finding an excellent agreement with the rates reported from the simulations. We have also explored the overall properties of these detections such as the presence of a colour-magnitude relation, the evolution of the photometric blue fraction and the clustering of these sources in the different ALHAMBRA fields. Despite the small numbers, we observe tentative evidence that, for a fixed stellar mass, the environment is playing a crucial role at lower redshifts (z<0.5).
780. ALHAMBRA survey morphological catalogue
ID:
ivo://CDS.VizieR/J/MNRAS/435/3444
Title:
ALHAMBRA survey morphological catalogue
Short Name:
J/MNRAS/435/3444
Date:
21 Oct 2021
Publisher:
CDS
Description:
Advanced Large Homogeneous Area Medium Band Redshift Astronomical (ALHAMBRA) is photometric survey designed to trace the cosmic evolution and cosmic variance. It covers a large area of ~4deg^2^ in eight fields, where seven fields overlap with other surveys, allowing us to have complementary data in other wavelengths. All observations were carried out in 20 continuous, medium band (30nm width) optical and 3 near-infrared (JHK) bands, providing the precise measurements of photometric redshifts. In addition, morphological classification of galaxies is crucial for any kind of galaxy formation and cosmic evolution studies, providing the information about star formation histories, their environment and interactions, internal perturbations, etc. We present a morphological classification of >40000 galaxies in the ALHAMBRA survey. We associate to every galaxy a probability to be early type using the automated Bayesian code galsvm. Despite of the spatial resolution of the ALHAMBRA images (~1arcsec), for 22051 galaxies, we obtained the contamination by other type of less than 10 percent. Of those, 1640 and 10322 galaxies are classified as early- (down to redshifts ~0.5) and late-type (down to redshifts ~1.0), respectively, with magnitudes F_613W_<=22.0. In addition, for magnitude range 22.0<F_613W_<=23.0, we classified other 10089 late-type galaxies with redshifts <=1.3. We show that the classified objects populate the expected regions in the colour-mass and colour-magnitude planes. The presented data set is especially attractive given the homogeneous multiwavelength coverage available in the ALHAMBRA fields, and is intended to be used in a variety of scientific applications. The low-contamination catalogue (<10 percent) is made publicly available with this paper.

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