- ID:
- ivo://CDS.VizieR/J/ApJ/729/22
- Title:
- SEDs of galaxy cluster members
- Short Name:
- J/ApJ/729/22
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from a study of AGNs and their host galaxies found in low-redshift galaxy clusters. We fit model spectral energy distributions (SEDs) to the combined visible and mid-infrared (MIR) photometry of cluster members and use these model SEDs to determine stellar masses and star formation rates (SFRs). We identify two populations of AGNs, the first based on their X-ray luminosities (X-ray AGNs) and the second based on the presence of a significant AGN component in their model SEDs (IR AGNs). We find that the two AGN populations are nearly disjoint; only 8 out of 44 AGNs are identified with both techniques.
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2012. SEDs of M33 HII regions
- ID:
- ivo://CDS.VizieR/J/A+A/552/A140
- Title:
- SEDs of M33 HII regions
- Short Name:
- J/A+A/552/A140
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Within the framework of the Herschel M33 extended survey HerM33es and in combination with multi-wavelength data we study the spectral energy distribution (SED) of a set of HII regions in the Local Group galaxy M33 as a function of the morphology. We analyse the emission distribution in regions with different morphologies and present models to infer the H{alpha} emission measure observed for HII regions with well defined morphology. We present a catalogue of 119 HII regions morphologically classified: 9 filled, 47 mixed, 36 shell, and 27 clear shell HII regions. For each object we extracted the photometry at twelve available wavelength bands, covering a wide wavelength range from FUV-1516{AA} (GALEX) to IR-250um (Herschel), and we obtained the SED for each object. We also obtained emission line profiles in vertical and horizontal directions across the regions to study the location of the stellar, ionised gas, and dust components. We constructed a simple geometrical model for the clear shell regions, whose properties allowed us to infer the electron density of these regions.
- ID:
- ivo://CDS.VizieR/J/ApJS/220/11
- Title:
- SEDs of Spitzer YSOs in the Gould Belt
- Short Name:
- J/ApJS/220/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the full catalog of Young Stellar Objects (YSOs) identified in the 18 molecular clouds surveyed by the Spitzer Space Telescope "cores to disks" (c2d) and "Gould Belt" (GB) Legacy surveys. Using standard techniques developed by the c2d project, we identify 3239 candidate YSOs in the 18 clouds, 2966 of which survive visual inspection and form our final catalog of YSOs in the GB. We compile extinction corrected spectral energy distributions for all 2966 YSOs and calculate and tabulate the infrared spectral index, bolometric luminosity, and bolometric temperature for each object. We find that 326 (11%), 210 (7%), 1248 (42%), and 1182 (40%) are classified as Class 0+I, Flat-spectrum, Class II, and Class III, respectively, and show that the Class III sample suffers from an overall contamination rate by background Asymptotic Giant Branch stars between 25% and 90%. Adopting standard assumptions, we derive durations of 0.40-0.78Myr for Class 0+I YSOs and 0.26-0.50Myr for Flat-spectrum YSOs, where the ranges encompass uncertainties in the adopted assumptions. Including information from (sub)millimeter wavelengths, one-third of the Class 0+I sample is classified as Class 0, leading to durations of 0.13-0.26Myr (Class 0) and 0.27-0.52Myr (Class I). We revisit infrared color-color diagrams used in the literature to classify YSOs and propose minor revisions to classification boundaries in these diagrams. Finally, we show that the bolometric temperature is a poor discriminator between Class II and Class III YSOs.
- ID:
- ivo://CDS.VizieR/J/ApJ/759/6
- Title:
- SEDs of type I AGN in COSMOS. I. XMM-COSMOS
- Short Name:
- J/ApJ/759/6
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The "Cosmic Evolution Survey" (COSMOS) enables the study of the spectral energy distributions (SEDs) of active galactic nuclei (AGNs) because of the deep coverage and rich sampling of frequencies from X-ray to radio. Here we present an SED catalog of 413 X-ray (XMM-Newton)-selected type 1 (emission line FWHM>2000km/s) AGNs with Magellan, SDSS, or VLT spectrum. The SEDs are corrected for Galactic extinction, broad emission line contributions, constrained variability, and host galaxy contribution. We present the mean SED and the dispersion SEDs after the above corrections in the rest-frame 1.4GHz to 40keV, and show examples of the variety of SEDs encountered. In the near-infrared to optical (rest frame ~8{mu}m-4000{AA}), the photometry is complete for the whole sample and the mean SED is derived from detections only. Reddening and host galaxy contamination could account for a large fraction of the observed SED variety.
2015. Segue 3 VI photometry
- ID:
- ivo://CDS.VizieR/J/MNRAS/433/1966
- Title:
- Segue 3 VI photometry
- Short Name:
- J/MNRAS/433/1966
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Deep Galileo (Telescopio Nazionale Galileo) B, V and I images of Segue 3, reaching V~25, reveal that it is the youngest globular cluster known so far in the Galaxy. A young age of 3.2Gyr is found, differently from a previous estimate of 12Gyr. It also appears to be moderately metal rich with [Fe/H]~-0.8, rather than [Fe/H]~-1.7, as previously suggested by Fadely et al. (2011AJ....142...88F, Cat. J/AJ/142/88). A main difference in the age derivation relative to Fadely et al. comes from the consideration of subgiant branch stars in the isochrone fitting. A deduced distance of d_{sun}_=29.1kpc is compatible with the outer halo location of other low luminosity globular clusters.
- ID:
- ivo://CDS.VizieR/J/ApJ/552/289
- Title:
- Semiregular variable stars in Baade's windows
- Short Name:
- J/ApJ/552/289
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- By cross-correlating the results of two recent large-scale surveys, the general properties of a well-defined sample of semiregular variable stars have been determined. ISOGAL mid-infrared photometry (7 and 15{mu}m and MACHO V and R light curves are assembled for approximately 300 stars in the Baade's windows of low extinction toward the Galactic bulge. These stars are mainly giants of late M spectral type, evolving along the asymptotic giant branch (AGB). They are found to possess a wide and continuous distribution of pulsation periods and to obey an approximate logP-M_bol_ relation or set of such relations.
- ID:
- ivo://CDS.VizieR/J/A+A/555/A63
- Title:
- Semi-sinusoidal variability with CoRoT
- Short Name:
- J/A+A/555/A63
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To date, the CoRoT space mission has produced more than 124471 light curves. Classifying these curves in terms of unambiguous variability behavior is mandatory for obtaining an unbiased statistical view on their controlling root-causes. The present study provides an overview of semi-sinusoidal light curves observed by the CoRoT exo-field CCDs. We selected a sample of 4206 light curves presenting well-defined semi-sinusoidal signatures. The variability periods were computed based on Lomb-Scargle periodograms, harmonic fits, and visual inspection.
- ID:
- ivo://CDS.VizieR/J/MNRAS/469/4341
- Title:
- Seven recent novae BVI light curves
- Short Name:
- J/MNRAS/469/4341
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The BVI light curves of seven recent novae (i.e. V1534 Sco, V1535 Sco, V2949 Oph, V3661 Oph, MASTER OT J010603.18-744715.8, TCP J18102829-2729590 and ASASSN-16ma) have been extensively mapped with daily robotic observations from Atacama (Chile): five belong to the Galactic bulge, one to the Small Magellanic Cloud and another is a Galactic disc object. The two programme novae detected in {gamma}-rays by Fermi-LAT (i.e. TCP J18102829-2729590 and ASASSN-16ma) are bulge objects with unevolved companions. They distinguish themselves by showing a double-component optical light curve. The first component to develop is the fireball from freely expanding, ballistic-launched ejecta, with a time of passage through maximum that is strongly dependent on wavelength (~1d delay between the B and I bands). The second component, emerging simultaneously with the nova detection in {gamma}-rays, evolves at a slower pace, its optical brightness being proportional to the {gamma}-ray flux, and its passage through maximum not dependent on wavelength. The fact that {gamma}-rays are detected at a flux level that differs by four times from novae at the distance of the bulge seems to suggest that {gamma}-ray emission is not a widespread property of normal novae. We discuss the advantages offered by high-quality photometric observations collected with only one telescope (as opposed to data provided by a number of different instruments). We also observe the effects of the wavelength dependence of fireball expansion, the recombination in the flashed wind of a giant companion, the subtle presence of hiccups and plateaus, and the super-soft X-ray emission and its switch-off. Four programme novae (V2949 Oph, V3661 Oph, TCP J18102829-2729590 and ASASSN-16ma) have normal dwarf companions: V1534 Sco contains an M3 III giant, V1535 Sco a K-type giant and MASTER OT J010603.18-744715.8 a subgiant. We also comment briefly on the maximum absolute magnitude relation with decline time (MMRD).
2019. SEXSI Spitzer catalog
- ID:
- ivo://CDS.VizieR/J/ApJ/708/584
- Title:
- SEXSI Spitzer catalog
- Short Name:
- J/ApJ/708/584
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We compare the relative merits of active galactic nuclei (AGNs) selection at X-ray and mid-infrared wavelengths using data from moderately deep fields observed by both Chandra and Spitzer. The X-ray-selected AGN sample and associated photometric and spectroscopic optical follow-up are drawn from a subset of fields studied as part of the Serendipitous Extragalactic X-ray Source Identification (SEXSI) program. Mid-infrared data in these fields are derived from targeted and archival Spitzer imaging, and mid-infrared AGN selection is accomplished primarily through application of the Infrared Array Camera (IRAC) color-color AGN "wedge" selection technique. Nearly all X-ray sources in these fields which exhibit clear spectroscopic signatures of AGN activity have mid-infrared colors consistent with IRAC AGN selection. These are predominantly the most luminous X-ray sources. X-ray sources that lack high-ionization and/or broad lines in their optical spectra are far less likely to be selected as AGNs by mid-infrared color selection techniques. The fraction of X-ray sources identified as AGNs in the mid-infrared increases monotonically as the X-ray luminosity increases. Conversely, only 22% of mid-infrared-selected AGNs are detected at X-ray energies in the moderately deep (t_exp_~100ks) SEXSI Chandra data.
- ID:
- ivo://CDS.VizieR/J/ApJ/788/159
- Title:
- 17 Seyfert 1 galaxies light curves
- Short Name:
- J/ApJ/788/159
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a dust reverberation survey for 17 nearby Seyfert 1 galaxies, which provides the largest homogeneous data collection for the radius of the innermost dust torus. A delayed response of the K-band light curve after the V-band light curve was found for all targets, and 49 measurements of lag times between the flux variation of the dust emission in the K band and that of the optical continuum emission in the V band were obtained by the cross-correlation function analysis and also by an alternative method for estimating the maximum likelihood lag. The lag times strongly correlated with the optical luminosity in the luminosity range of M_V_=-16 to -22 mag, and the regression analysis was performed to obtain the correlation log {Delta}t (days)=-2.11 -0.2 M_V_ assuming {Delta}t{prop.to}L^0.5^, which was theoretically expected. We discuss the possible origins of the intrinsic scatter of the dust lag-luminosity correlation, which was estimated to be approximately 0.13 dex, and we find that the difference of internal extinction and delayed response of changes in lag times to the flux variations could have partly contributed to intrinsic scatter. However, we could not detect any systematic change of the correlation with the subclass of the Seyfert type or the Eddington ratio. Finally, we compare the dust reverberation radius with the near-infrared interferometric radius of the dust torus and the reverberation radius of broad Balmer emission lines. The interferometric radius in the K band was found to be systematically larger than the dust reverberation radius in the same band by the about a factor of two, which could be interpreted by the difference between the flux-weighted radius and response-weighted radius of the innermost dust torus. The reverberation radius of the broad Balmer emission lines was found to be systematically smaller than the dust reverberation radius by about a factor of four to five, which strongly supports the unified scheme of the Seyfert type of active galactic nuclei (AGNs). Moreover, we examined the radius-luminosity correlations for the hard X-ray (14-195 keV) and the [O IV] {lambda}25.89 {mu}m emission-line luminosities, which would be applicable for obscured AGNs.
