Catálogo de publicaciones - revistas

<jats:title>Abstract</jats:title> <jats:p>We present new central stellar velocity dispersions for 484 Sy 1.9 and Sy 2 from the second data release of the Swift/BAT AGN Spectroscopic Survey (BASS DR2). This constitutes the largest study of velocity dispersion measurements in X-ray-selected obscured active galactic nuclei (AGN) with 956 independent measurements of the Ca <jats:sc>ii</jats:sc> H and K <jats:italic>λ</jats:italic>3969, 3934 and Mg I <jats:italic>λ</jats:italic>5175 region (3880–5550 Å) and the calcium triplet region (8350–8730 Å) from 642 spectra mainly from VLT/X-Shooter or Palomar/DoubleSpec. Our sample spans velocity dispersions of 40–360 km s<jats:sup>1</jats:sup>, corresponding to 4–5 orders of magnitude in black hole mass (<jats:italic>M</jats:italic> <jats:sub>BH</jats:sub> = 10<jats:sup>5.5−9.6</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>), bolometric luminosity (<jats:italic>L</jats:italic> <jats:sub>bol</jats:sub> ∼ 10<jats:sup>42–46</jats:sup> erg s<jats:sup>−1</jats:sup>), and Eddington ratio (<jats:italic>L</jats:italic>/<jats:italic>L</jats:italic> <jats:sub>Edd</jats:sub> ∼ 10<jats:sup>−5</jats:sup> to 2). For 281 AGN, our data and analysis provide the first published central velocity dispersions, including six AGN with low-mass black holes (<jats:italic>M</jats:italic> <jats:sub>BH</jats:sub> = 10<jats:sup>5.5−6.5</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>), discovered thanks to high spectral resolution observations (<jats:italic>σ</jats:italic> <jats:sub>inst</jats:sub> ∼ 25 km s<jats:sup>−1</jats:sup>). The survey represents a significant advance with a nearly complete census of velocity dispersions of hard X-ray–selected obscured AGN with measurements for 99% of nearby AGN (<jats:italic>z</jats:italic> &lt; 0.1) outside the Galactic plane (∣<jats:italic>b</jats:italic>∣ &gt; 10°). The BASS AGN have much higher velocity dispersions than the more numerous optically selected narrow-line AGN (i.e., ∼150 versus ∼100 km s<jats:sup>−1</jats:sup>) but are not biased toward the highest velocity dispersions of massive ellipticals (i.e., &gt;250 km s<jats:sup>−1</jats:sup>). Despite sufficient spectral resolution to resolve the velocity dispersions associated with the bulges of small black holes (∼10<jats:sup>4–5</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>), we do not find a significant population of super-Eddington AGN. Using estimates of the black hole sphere of influence from velocity dispersion, direct stellar and gas black hole mass measurements could be obtained with existing facilities for more than ∼100 BASS AGN.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We present the BAT AGN Spectroscopic Survey (BASS) Near-infrared Data Release 2 (DR2), a study of 168 nearby (<jats:inline-formula> <jats:tex-math> <?CDATA $\bar{z}=0.04$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover accent="true"> <mml:mrow> <mml:mi>z</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>¯</mml:mo> </mml:mrow> </mml:mover> <mml:mo>=</mml:mo> <mml:mn>0.04</mml:mn> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjsac5b66ieqn1.gif" xlink:type="simple" /> </jats:inline-formula>, <jats:italic>z</jats:italic> &lt; 0.6) active galactic nuclei (AGN) from the all-sky Swift Burst Array Telescope X-ray survey observed with the Very Large Telescope (VLT)/X-shooter in the near-infrared (NIR; 0.8–2.4 <jats:italic>μ</jats:italic>m). We find that 49/109 (45%) Seyfert 2 and 35/58 (60%) Seyfert 1 galaxies observed with VLT/X-shooter show at least one NIR high-ionization coronal line (CL; ionization potential <jats:italic>χ</jats:italic> &gt; 100 eV). Comparing the emission of the [Si <jats:sc>vi</jats:sc>] <jats:italic>λ</jats:italic>1.9640 CL with the X-ray emission for the DR2 AGN, we find a significantly tighter correlation, with a lower scatter (0.37 dex) than that for the optical [O <jats:sc>iii</jats:sc>] <jats:italic>λ</jats:italic>5007 line (0.71 dex). We do not find any correlation between CL emission and the X-ray photon index Γ. We find a clear trend of line blueshifts with increasing ionization potential in several CLs, such as [Si <jats:sc>vi</jats:sc>] <jats:italic>λ</jats:italic>1.9640, [Si <jats:sc>x</jats:sc>] <jats:italic>λ</jats:italic>1.4300, [S <jats:sc>viii</jats:sc>] <jats:italic>λ</jats:italic>0.9915, and [S <jats:sc>ix</jats:sc>] <jats:italic>λ</jats:italic>1.2520, indicating the radial structure of the CL region. Finally, we find a strong underestimation bias in black hole mass measurements of Sy 1.9 using broad H<jats:italic>α</jats:italic> due to the presence of significant dust obscuration. In contrast, the broad Pa<jats:italic>α</jats:italic> and Pa<jats:italic>β</jats:italic> emission lines are in agreement with the <jats:italic>M</jats:italic>–<jats:italic>σ</jats:italic> relation. Based on the combined DR1 and DR2 X-shooter sample, the NIR BASS sample now comprises 266 AGN with rest-frame NIR spectroscopic observations, the largest set assembled to date.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Virial black hole (BH) mass (<jats:italic>M</jats:italic> <jats:sub>BH</jats:sub>) determination directly involves knowing the broad-line region (BLR) clouds’ velocity distribution, their distance from the central supermassive BH (<jats:italic>R</jats:italic> <jats:sub>BLR</jats:sub>), and the virial factor (<jats:italic>f</jats:italic>). Understanding whether biases arise in <jats:italic>M</jats:italic> <jats:sub>BH</jats:sub> estimation with increasing obscuration is possible only by studying a large (<jats:italic>N</jats:italic> &gt; 100) statistical sample of obscuration-unbiased (hard) X-ray-selected active galactic nuclei (AGNs) in the rest-frame near-infrared (0.8–2.5 <jats:italic>μ</jats:italic>m) since it penetrates deeper into the BLR than the optical. We present a detailed analysis of 65 local Burst Alert Telescope (BAT) selected Seyfert galaxies observed with Magellan/FIRE. Adding these to the near-infrared BAT AGN spectroscopic survey database, we study a total of 314 unique near-infrared spectra. While the FWHMs of H<jats:italic>α</jats:italic> and near-infrared broad lines (He <jats:sc>i</jats:sc>, Pa<jats:italic>β</jats:italic>, Pa<jats:italic>α</jats:italic>) remain unbiased to either BLR extinction or X-ray obscuration, the H<jats:italic>α</jats:italic> broad-line luminosity is suppressed when <jats:italic>N</jats:italic> <jats:sub>H</jats:sub> ≳ 10<jats:sup>21</jats:sup> cm<jats:sup>−2</jats:sup>, systematically underestimating <jats:italic>M</jats:italic> <jats:sub>BH</jats:sub> by 0.23–0.46 dex. Near-infrared line luminosities should be preferred to H<jats:italic>α</jats:italic> until <jats:italic>N</jats:italic> <jats:sub>H</jats:sub> &lt; 10<jats:sup>22</jats:sup> cm<jats:sup>−2</jats:sup>, while at higher obscuration a less-biased <jats:italic>R</jats:italic> <jats:sub>BLR</jats:sub> proxy should be adopted. We estimate <jats:italic>f</jats:italic> for Seyfert 1 and 2 using two obscuration-unbiased <jats:italic>M</jats:italic> <jats:sub>BH</jats:sub> measurements, i.e., the stellar velocity dispersion and a BH mass prescription based on near-infrared and X-ray, and find that the virial factors do not depend on the redshift or obscuration, but some broad lines show a mild anticorrelation with <jats:italic>M</jats:italic> <jats:sub>BH</jats:sub>. Our results show the critical impact obscuration can have on BLR characterization and the importance of the near-infrared and X-rays for a less-biased view of the BLR.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We determine the low-redshift X-ray luminosity function, active black hole mass function (BHMF), and Eddington ratio distribution function (ERDF) for both unobscured (Type 1) and obscured (Type 2) active galactic nuclei (AGNs), using the unprecedented spectroscopic completeness of the BAT AGN Spectroscopic Survey (BASS) data release 2. In addition to a straightforward 1/<jats:italic>V</jats:italic> <jats:sub>max</jats:sub> approach, we also compute the intrinsic distributions, accounting for sample truncation by employing a forward-modeling approach to recover the observed BHMF and ERDF. As previous BHMFs and ERDFs have been robustly determined only for samples of bright, broad-line (Type 1) AGNs and/or quasars, ours are the first directly observationally constrained BHMF and ERDF of Type 2 AGNs. We find that after accounting for all observational biases, the intrinsic ERDF of Type 2 AGNs is significantly more skewed toward lower Eddington ratios than the intrinsic ERDF of Type 1 AGNs. This result supports the radiation-regulated unification scenario, in which radiation pressure dictates the geometry of the dusty obscuring structure around an AGN. Calculating the ERDFs in two separate mass bins, we verify that the derived shape is consistent, validating the assumption that the ERDF (shape) is mass-independent. We report the local AGN duty cycle as a function of mass and Eddington ratio, by comparing the BASS active BHMF with the local mass function for all supermassive black holes. We also present the <jats:inline-formula> <jats:tex-math> <?CDATA $\mathrm{log}N-\mathrm{log}S$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>log</mml:mi> <mml:mi>N</mml:mi> <mml:mo>−</mml:mo> <mml:mi>log</mml:mi> <mml:mi>S</mml:mi> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjsac5b64ieqn1.gif" xlink:type="simple" /> </jats:inline-formula> of the Swift/BAT 70 month sources.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Solar images observed in different channels with different instruments are crucial to the study of solar activity. However, the images have different fields of view, causing them to be misaligned. It is essential to accurately register the images for studying solar activity from multiple perspectives. Image registration is described as an optimizing problem from an image to be registered to a reference image. In this paper, we proposed a novel coarse-to-fine solar image registration method to register the multichannel solar images. In the coarse registration step, we used the regular step gradient descent algorithm as an optimizer to maximize the normalized cross correlation metric. The fine registration step uses the Powell–Brent algorithms as an optimizer and brings the Mattes mutual information similarity metric to the minimum. We selected five pairs of images with different resolutions, rotation angles, and shifts to compare and evaluate our results to those obtained by scale-invariant feature transform and phase correlation. The images are observed by the 1.6 m Goode Solar Telescope at Big Bear Solar Observatory and the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory. Furthermore, we used the mutual information and registration time criteria to quantify the registration results. The results prove that the proposed method not only reaches better registration precision but also has better robustness. Meanwhile, we want to highlight that the method can also work well for the time-series solar image registration.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We present a catalog of 5598 ultra-diffuse galaxy (UDG) candidates with effective radius <jats:italic>r</jats:italic> <jats:sub> <jats:italic>e</jats:italic> </jats:sub> &gt; 5.″3 distributed throughout the southern portion of the DESI Legacy Imaging Survey covering ∼15,000 deg<jats:sup>2</jats:sup>. The catalog is most complete for physically large (<jats:italic>r</jats:italic> <jats:sub> <jats:italic>e</jats:italic> </jats:sub> &gt; 2.5 kpc) UDGs lying in the redshift range 1800 ≲ <jats:italic>cz</jats:italic>/km s<jats:sup>−1</jats:sup> ≲ 7000, where the lower bound is defined by where incompleteness becomes significant for large objects on the sky and the upper bound by our minimum angular size selection criterion. Because physical size is integral to the definition of a UDG, we develop a method of distance estimation using existing redshift surveys. With three different galaxy samples, two of which contain UDGs with spectroscopic redshifts, we estimate that the method has a redshift accuracy of ∼75% when the method converges, although larger, more representative spectroscopic UDG samples are needed in order to fully understand the behavior of the method. We are able to estimate distances for 1079 of our UDG candidates (19%). Finally, to illustrate some uses of the catalog, we present both distance-independent and distance-dependent results. In the latter category, we establish that the red sequence of UDGs lies on the extrapolation of the red sequence relation for bright ellipticals and that the environment–color relation is at least qualitatively similar to that of high surface brightness galaxies. Both of these results challenge some of the models proposed for UDG evolution.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We present a catalog of spectroscopically measured redshifts over 0 &lt; <jats:italic>z</jats:italic> &lt; 2 and emission-line fluxes for 1440 galaxies. The majority (∼65%) of the galaxies come from the HALO7D survey, with the remainder from the DEEPwinds program. This catalog includes redshifts for 646 dwarf galaxies with <jats:inline-formula> <jats:tex-math> <?CDATA $\mathrm{log}({M}_{\star }/{M}_{\odot })\lt 9.5$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>log</mml:mi> <mml:mo stretchy="false">(</mml:mo> <mml:msub> <mml:mrow> <mml:mi>M</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>⋆</mml:mo> </mml:mrow> </mml:msub> <mml:mrow> <mml:mo stretchy="true">/</mml:mo> </mml:mrow> <mml:msub> <mml:mrow> <mml:mi>M</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>⊙</mml:mo> </mml:mrow> </mml:msub> <mml:mo stretchy="false">)</mml:mo> <mml:mo>&lt;</mml:mo> <mml:mn>9.5</mml:mn> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjsac6cdfieqn1.gif" xlink:type="simple" /> </jats:inline-formula>. Eight-hundred and ten catalog galaxies did not have previously published spectroscopic redshifts, including 454 dwarf galaxies. HALO7D used the DEIMOS spectrograph on the Keck II telescope to take very deep (up to 32 hr exposure, with a median of ∼7 hr) optical spectroscopy in the COSMOS, EGS, GOODS-North, and GOODS-South CANDELS fields, and in some areas outside CANDELS. We compare our redshift results to existing spectroscopic and photometric redshifts in these fields, finding only a 1% rate of discrepancy with other spectroscopic redshifts. We measure a small increase in median photometric redshift error (from 1.0% to 1.3%) and catastrophic outlier rate (from 3.5% to 8%) with decreasing stellar mass. We obtained successful redshift fits for 75% of massive galaxies, and demonstrate a similar 70%–75% successful redshift measurement rate in <jats:inline-formula> <jats:tex-math> <?CDATA $8.5\lt \mathrm{log}({M}_{\star }/{M}_{\odot })\lt 9.5$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>8.5</mml:mn> <mml:mo>&lt;</mml:mo> <mml:mi>log</mml:mi> <mml:mo stretchy="false">(</mml:mo> <mml:msub> <mml:mrow> <mml:mi>M</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>⋆</mml:mo> </mml:mrow> </mml:msub> <mml:mrow> <mml:mo stretchy="true">/</mml:mo> </mml:mrow> <mml:msub> <mml:mrow> <mml:mi>M</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>⊙</mml:mo> </mml:mrow> </mml:msub> <mml:mo stretchy="false">)</mml:mo> <mml:mo>&lt;</mml:mo> <mml:mn>9.5</mml:mn> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjsac6cdfieqn2.gif" xlink:type="simple" /> </jats:inline-formula> galaxies, suggesting similar survey sensitivity in this low-mass range. We describe the redshift, mass, and color–magnitude distributions of the catalog galaxies, finding HALO7D galaxies representative of CANDELS galaxies up to <jats:italic>i</jats:italic>-band magnitudes of 25. The catalogs presented will enable studies of star formation, the mass–metallicity relation, star formation–morphology relations, and other properties of the <jats:italic>z</jats:italic> ∼ 0.7 dwarf galaxy population.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>This study developed an automated identification procedure for compact clouds with broad velocity widths in the spectral-line data cubes of highly crowded regions. The procedure was applied to the CO <jats:italic>J</jats:italic> = 3 − 2 line data, obtained using the James Clerk Maxwell Telescope, to identify 184 high-velocity dispersion compact clouds (HVDCCs), which are a category of peculiar molecular clouds found in the central molecular zone of our Galaxy. A list of HVDCCs in the area −1.°4 ≤ <jats:italic>l</jats:italic> ≤ +2.°0, −0.°25 ≤ <jats:italic>b</jats:italic> ≤ +0.°25 was presented with their physical parameters, CO <jats:italic>J</jats:italic> = 3 − 2/<jats:italic>J</jats:italic> = 1 − 0 intensity ratios, and morphological classifications. Consequently, the list provides several intriguing sources that may have been driven by encounters with pointlike massive objects, local energetic events, or cloud-to-cloud collisions.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We present a study of the correlation between 22 GHz water maser emission and far-infrared/submillimeter (IR/sub-mm) sources. The generalized linear model (GLM) is used to predict H<jats:sub>2</jats:sub>O maser detection in a particular source with defined physical parameters. We checked the GLM predictions by observing a sample of selected sources with the Effelsberg 100 m telescope. In total, 359 sources were observed. H<jats:sub>2</jats:sub>O masers were detected in 124 sources, with 56 new detections. We found 22 sources with a significant flux variability. Using the GLM analysis, we estimate that 2392 ± 339 star formation regions (SFRs) in the Galaxy may harbor H<jats:sub>2</jats:sub>O masers detectable by single-dish observations at the noise level of ∼0.05 Jy. Analyzing the luminosity-to-mass ratio (<jats:italic>L</jats:italic>/<jats:italic>M</jats:italic>) of the ATLASGAL and Hi-GAL clumps associated with different maser species, we find that 22 GHz water masers have significantly lower values of <jats:italic>L</jats:italic>/<jats:italic>M</jats:italic> in comparison to 6.7 GHz class II methanol and 1665 MHz OH masers. This implies that 22 GHz water masers may appear prior to 6.7 GHz methanol and OH masers in the evolutionary sequence of SFRs. From the analysis of physical offsets between host clumps and maser interferometric positions, we found no significant difference between the H<jats:sub>2</jats:sub>O and class II methanol maser offsets against the host clump position. We conclude that the tight association between water masers and IR/sub-mm sources may provide insight into the pumping conditions of these masers and the evolutionary stages of their onset.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>New instruments sensitive to chromospheric radiation at X-ray, UV, visible, IR, and submillimeter wavelengths have become available that significantly enhance our ability to understand the bidirectional flow of energy through the chromosphere. We describe the calibration, coalignment, initial results, and public release of a new data set combining a large number of these instruments to obtain multiwavelength photospheric, chromospheric, and coronal observations capable of improving our understanding of the connectivity between the photosphere and the corona via transient brightenings and wave signatures. The observations center on a bipolar region of enhanced-network magnetic flux near disk center on SOL2017-03-17T14:00–17:00. The comprehensive data set provides one of the most complete views to date of chromospheric activity related to small-scale brightenings in the corona and chromosphere. Our initial analysis shows a strong spatial correspondence between the areas of broadest width of the hydrogen-<jats:italic>α</jats:italic> spectral line and the hottest temperatures observed in Atacama Large Millimeter/submillimeter Array (ALMA) Band 3 radio data, with a linear coefficient of 6.12 × 10<jats:sup>−5</jats:sup>Å/K. The correspondence persists for the duration of cotemporal observations (≈60 m). Numerous transient brightenings were observed in multiple data series. We highlight a single, well-observed transient brightening in a set of thin filamentary features with a duration of 20 minutes. The timing of the peak intensity transitions from the cooler (ALMA, 7000 K) to the hotter (XRT, 3 MK) data series.</jats:p>