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1601. Historic light curves of 3 known blazars
ID:
ivo://CDS.VizieR/J/AJ/139/2425
Title:
Historic light curves of 3 known blazars
Short Name:
J/AJ/139/2425
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the historic photographic light curves of three little known blazars (two BL Lac objects and one FSRQ), GB6 J1058+5628, GB6 J1148+5254, and GB6 J1209+4119, spanning a time interval of about 50 years, mostly built using the Asiago plate archive. All objects show evident long-term variability, over which short-term variations are superposed. One source, GB6 J1058+5628, showed a marked quasi-periodic variability of 1mag on timescale of about 6.3 years, making it one of the few BL Lac objects with a quasi-periodic behavior.
1602. HKE Sydney Catalog
ID:
ivo://CDS.VizieR/I/73
Title:
HKE Sydney Catalog
Short Name:
I/73
Date:
21 Oct 2021
Publisher:
CDS
Description:
The methods for constructing a catalogue of 20457 star positions for the epoch 1964 between -48 and -58{deg} declination are described. The positions were obtained by the overlap method, and images generated by a coarse diffraction grating were employed to control magnitude-related effects on the position. A selection of about 2 faint Astrographic Catalog (AC) stars per square degree was included to serve as material for the eventual determination of magnitude effects on the AC positions. The standard error of a catalogued position estimate based on 2 images is 0.12'' in either coordinate.
1603. HLF photometric catalog in GOODS-S v2.0
ID:
ivo://CDS.VizieR/J/ApJS/244/16
Title:
HLF photometric catalog in GOODS-S v2.0
Short Name:
J/ApJS/244/16
Date:
21 Oct 2021
Publisher:
CDS
Description:
This manuscript describes the public release of the Hubble Legacy Fields (HLF) project photometric catalog for the extended GOODS-South region from the Hubble Space Telescope (HST) archival program AR-13252. The analysis is based on the version 2.0 HLF data release that now includes all ultraviolet (UV) imaging, combining three major UV surveys. The HLF data combines over a decade worth of 7475 exposures taken in 2635 orbits totaling 6.3Ms with the HST Advanced Camera for Surveys Wide Field Channel (ACS/WFC) and the Wide Field Camera 3 (WFC3) UVIS/IR Channels in the greater GOODS-S extragalactic field, covering all major observational efforts (e.g., GOODS, GEMS, CANDELS, ERS, UVUDF, and many other programs; see Illingworth+ arXiv:1606.00841). The HLF GOODS-S catalogs include photometry in 13 bandpasses from the UV (WFC3/UVIS F225W, F275W, and F336W filters), optical (ACS/WFC F435W, F606W, F775W, F814W and F850LP filters), to near-infrared (WFC3/IR F098M, F105W, F125W, F140W and F160W filters). Such a data set makes it possible to construct the spectral energy distributions (SEDs) of objects over a wide wavelength range from high-resolution mosaics that are largely contiguous. Here, we describe a photometric analysis of 186474 objects in the HST imaging at wavelengths 0.2-1.6{mu}m. We detect objects from an ultra-deep image combining the PSF-homogenized and noise-equalized F850LP, F125W, F140W, and F160W images, including Gaia astrometric corrections. SEDs were determined by carefully taking the effects of the point-spread function in each observation into account.
1604. HLock01-LAB 2D spectrum
ID:
ivo://CDS.VizieR/J/A+A/629/A23
Title:
HLock01-LAB 2D spectrum
Short Name:
J/A+A/629/A23
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the discovery of HLock01-LAB, a luminous and large Ly{alpha} nebula at z=3.326. Medium-band imaging and long-slit spectroscopic observations with the Gran Telescopio Canarias reveal extended emission in the Ly{alpha} 1215{AA}, CIV 1550{AA}, and HeII 1640{AA} lines over ~100kpc, and a total luminosity L(Ly{alpha})=(6.4+/-0.1)x10^44^erg/s. HLock01-LAB presents an elongated morphology aligned with two faint radio sources contained within the central ~8kpc of the nebula. The radio structures are consistent with faint radio jets or lobes of a central galaxy, whose spectrum shows nebular emission characteristic of a type-II active galactic nucleus (AGN). The continuum emission of the AGN at short wavelengths is however likely dominated by stellar emission of the host galaxy, for which we derive a stellar mass M*~2.3x10^11^M_{sun}_. Our kinematic analysis shows that the ionized gas is perturbed almost exclusively in the inner region between the radio structures, probably as a consequence of jet-gas interactions, whereas in the outer regions the ionized gas appears more quiescent. The detection of extended emission in CIV and CIII] indicates that the gas within the nebula is not primordial. Feedback may have enriched the halo at at least 50kpc from the nuclear region. Using rest-frame UV emission-line diagnostics, we find that the gas in the nebula is likely heated by the AGN. Nevertheless, at the center of the nebula we find extreme emission line ratios of Ly{alpha}/CIV~60 and Ly{alpha}/HeII~80, one of the highest values measured to date, and well above the standard values of photoionization models (Ly{alpha}/HeII ~30 for case B photoionization). Our data suggest that jet-induced shocks are likely responsible for the increase of the electron temperature and, thus, the observed Ly{alpha} enhancement in the center of the nebula. This scenario is further supported by the presence of radio structures and perturbed kinematics in this region. The large Ly{alpha} luminosity in HLock01-LAB is likely due to a combination of AGN photoionization and jet-induced shocks, highlighting the diversity of sources of energy powering Ly{alpha} nebulae. Future follow-up observations of HLock01-LAB will help to reveal the finer details of the excitation conditions of the gas induced by jets and to investigate the underlying cooling and feedback processes in this unique object.
1605. H narrow-band imaging of XMMU J2235.3-2557
ID:
ivo://CDS.VizieR/J/MNRAS/411/2009
Title:
H narrow-band imaging of XMMU J2235.3-2557
Short Name:
J/MNRAS/411/2009
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first results of a narrow-band photometric study of the massive galaxy cluster XMMU J2235.3-2557 at z=1.39. We obtained deep H narrow-band imaging with the Near InfraRed Imager and Spectrometer on Gemini North, corresponding to H{alpha} emission at the cluster's redshift. Our sample consists of 82 galaxies within a radius of ~500kpc, 10 of which are spectroscopically confirmed cluster members. 16 galaxies are identified as excess line-emitters.
1606. H narrow-band imaging of XMMU J2235.3-2557
ID:
ivo://CDS.VizieR/J/MNRAS/423/3652
Title:
H narrow-band imaging of XMMU J2235.3-2557
Short Name:
J/MNRAS/423/3652
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of an extended narrow-band H{alpha} study of the massive galaxy cluster XMMU J2235.3-2557 at z=1.39. This paper represents a follow-up study to our previous investigation of star formation in the cluster centre, extending our analysis out to a projected cluster radius of 1.5Mpc. Using the Near InfraRed Imager and Spectrograph on Gemini North Telescope we obtained deep H narrow-band imaging corresponding to the rest-frame wavelength of H{alpha} at the cluster's redshift. We identify a total of 163 potential cluster members in both pointings, excluding stars based on their near-infrared colours derived from VLT/HAWK-I imaging. Of these 163 objects 14 are spectroscopically confirmed cluster members, and 20 per cent are excess line emitters. We find no evidence of star formation activity within a radius of 200 kpc of the brightest cluster galaxy in the cluster core. Dust-corrected star formation rates (SFRs) of excess emitters outside this cluster quenching radius, R_Q_~200kpc, are on average <SFR>=2.7+/-1.0M_{sun}_/yr, but do not show evidence of increasing SFRs towards the extreme 1.5Mpc radius of the cluster. No individual cluster galaxy exceeds an SFR of 6M_{sun}_/yr. Massive galaxies (logM*/M_{sun}_>10.75) all have low specific SFRs (SSFRs, i.e. SFR per unit stellar mass). At fixed stellar mass, galaxies in the cluster centre have lower SSFRs than the rest of the cluster galaxies, which in turn have lower SSFRs than field galaxies at the same redshift by a factor of a few to 10. For the first time we can demonstrate through measurements of individual SFRs that already at very early epochs (at an age of the Universe of ~4.5Gyr) the suppression of star formation is an effect of the cluster environment which persists at fixed galaxy stellar mass.
1607. HNCO in planetary atmospheres.
ID:
ivo://CDS.VizieR/J/A+A/616/A150
Title:
HNCO in planetary atmospheres.
Short Name:
J/A+A/616/A150
Date:
21 Oct 2021
Publisher:
CDS
Description:
Time-resolved Fourier transform infrared emission spectroscopy, Fourier transform absorption infrared spectroscopy, and high-resolution UV-ViS emission spectroscopy have been exploited in order to characterize the chemistry of isocyanic acid (HNCO) under glow discharge conditions in planetary atmospheres. HNCO mixtures (i.e., composed of di-hydrogen or ammonia) have been investigated in order to unveil the possible reaction pathways leading to the synthesis of the key prebiotic molecule formamide (HCONH_2_), upon planetary atmospheres containing isocyanic acid in presence of di-hydrogen and, separately, of ammonia. In addition, ab initio Molecular Dynamics simulations coupled with a state-of-the-art metadynamics technique have been performed in order to identify the most likely chemical pathways connecting HNCO to formamide. It turned out that the direct hydrogenation of HNCO is thermodynamically favored. Incidentally, also the experimental results - supplied by a simplified kinetic model - proved the favorability of the reaction HNCO + H_2_ -> HCONH_2_ which, moreover, spontaneously takes place in unbiased ab initio Molecular Dynamics simulations carried out under the effect of intense electric fields.
1608. Homegeneous RI magnitudes in Kron system
ID:
ivo://CDS.VizieR/II/75
Title:
Homegeneous RI magnitudes in Kron system
Short Name:
II/75
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalogue (file "mean") contains homogeneous data in the photoelectric photometric system of Kron and Smith. The R magnitude and the R-I colour index have been collected from the literature published before January 1982. The homogenization method used in file "mean" has been described by Nicolet B. (1978, Astron. Astrophys. Suppl. 34,1).
1609. Homogeneous Means in the UBV System
ID:
ivo://CDS.VizieR/II/168
Title:
Homogeneous Means in the UBV System
Short Name:
II/168
Date:
21 Oct 2021
Publisher:
CDS
Description:
The present catalog supersedes an earlier edition of Nicolet (1978). It is a collection of weighted mean photoelectric values (V, B-V, U-B) for stars measured in the UBV system. The mean values were computed by combining all individual measurements compiled in the catalog of Mermilliod (1987), except those that were clearly found to be erroneous for some reason or another. Some newer observations compiled since 1987 are also included in the means. The procedure for computing the homogeneous means involved the calculation of normal averages weighted by the number of observations in each list (unity when not published). New weights are assigned based on the deviation of each value from the previous mean, then a new weighted mean is computed. This technique is not as rigorous as that used by Nicolet (comparison of each list with the standard system master list), but the latter cannot often be realized effectively in practice, since many lists do not contain enough stars in common with a standard list. Also, there are now so many references (more than 1500) that it is not feasible to analyze each publication with respect to a standard list. This edition of the catalog contains 92964 stars measured since the introduction of the UBV system in 1953. The data included are star identification in the Geneva coded numbering system, double and variable codes, UBV data and their standard deviations, and number of observations. A second file contains the definition of the coded numbering system. The catalog was prepared at the Institut d'Astronomie de l'Universite de Lausanne in Geneva.
1610. Homogeneous Photometry Bright Stars on DDO System
ID:
ivo://CDS.VizieR/II/80
Title:
Homogeneous Photometry Bright Stars on DDO System
Short Name:
II/80
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalogue of homogeneous photometry of bright stars on the DDO (System McClure and Forrester 1981) is a compilation of DDO photometry of 2196 bright G and K stars prepared from observations made at Kitt Peak National and Cerro Tololo Inter-American Observatories over the last several years using filter sets well matched to the standard system. The catalogue includes a large number of DDO stars whose data have been taken directly from the standard-star paper of McClure (1976AJ.....81..182M), plus a representative sample of stars selected from the Catalogue of Bright Stars (Hoffleit 1964, see Cat. V/50) and the Catalogue of High-Velocity Stars (Eggen 1964, see Cat. V/11) to have good velocities, spectral types and freedom from companion contamination. The catalogue contains HD Catalogue numbers, DM identifications; and the standard photometric indices of the DDO system. The number of observations from which each index was determined is also given, along with standard errors. The DDO 6-filter has the following peak wavelengths and widths: ------------------------ Filter Peak Width [nm] [nm] ------------------------ 35 346.0 38.3 38 381.5 33.0 41 416.6 8.3 42 425.7 7.3 45 451.7 7.6 48 488.6 18.6 ------------------------