Browsing by Author "Lamperti, Isabella"
Now showing 1 - 18 of 18
Results Per Page
Sort Options
- ItemBASS. XXI. The Data Release 2 Overview(2022) Koss, Michael J.; Trakhtenbrot, Benny ; Ricci, Claudio ; Bauer, Franz Erik; Treister, Ezequiel ; Mushotzky, Richard ; Urry, C. Megan ; Ananna, Tonima T. ; Baloković, Mislav ; den Brok, Jakob S. ; Cenko, S. Bradley ; Harrison, Fiona ; Ichikawa, Kohei ; Lamperti, Isabella; Lein, Amy ; Mejía-Restrepo, Julian E. ; Oh, Kyuseok ; Pacucci, Fabio ; Pfeifle, Ryan W. ; Powell, Meredith C. ; Privon, George C. ; Ricci, Federica; Salvato, Mara ; Schawinski, Kevin ; Shimizu, Taro ; Krista L. Smith; Stern, Daniel
- ItemBASS. XXII. The BASS DR2 AGN Catalog and Data(2022) Koss, Michael J. ; Ricci, Claudio ; Trakhtenbrot, Benny ; Oh, Kyuseok ; den Brok, Jakob S. ; Mejía-Restrepo, Julian E. ; Stern, Daniel ; Privon, George C. ; Treister, Ezequiel ; Powell, Meredith C.; Mushotzky, Richard ; Bauer, Franz Erik; Ananna, Tonima T. ; Baloković, Mislav ; Bär, Rudolf ; Becker, George ; Bessiere, Patricia ; Burtscher, Leonard ; Caglar, Turgay ; Congiu, Enrico ; Evans, Phil ; Harrison, Fiona ; Heida, Marianne ; Ichikawa, Kohei ; Kamraj, Nikita; Lamperti, Isabella; Pacucci, Fabio ; Ricci, Federica ; Riffel, Rogério; Rojas, Alejandra F. ; Schawinski, Kevin ; Temple, Matthew J. ; Urry, C. Megan ; Veilleux, Sylvain ; Williams, Jonathan
- ItemBASS. XXIV. The BASS DR2 Spectroscopic Line Measurements and AGN Demographics(2022) Oh, Kyuseok; Koss, Michael J.; Ueda, Yoshihiro; Stern, Daniel; Ricci, Claudio; Trakhtenbrot, Benny; Powell, Meredith C.; den Brok, Jakob S.; Lamperti, Isabella; Mushotzky, Richard; Ricci, Federica; Bar, Rudolf E.; Rojas, Alejandra F.; Ichikawa, Kohei; Riffel, Rogerio; Treister, Ezequiel; Harrison, Fiona; Urry, C. Megan; Bauer, Franz E.; Schawinski, KevinWe present the second catalog and data release of optical spectral line measurements and active galactic nucleus (AGN) demographics of the BAT AGN Spectroscopic Survey, which focuses on the Swift-BAT hard X-ray detected AGNs. We use spectra from dedicated campaigns and publicly available archives to investigate spectral properties of most of the AGNs listed in the 70 month Swift-BAT all-sky catalog; specifically, 743 of the 746 unbeamed and unlensed AGNs (99.6%). We find a good correspondence between the optical emission line widths and the hydrogen column density distributions using the X-ray spectra, with a clear dichotomy of AGN types for N (H) = 10(22) cm(-2). Based on optical emission-line diagnostics, we show that 48%-75% of BAT AGNs are classified as Seyfert, depending on the choice of emission lines used in the diagnostics. The fraction of objects with upper limits on line emission varies from 6% to 20%. Roughly 4% of the BAT AGNs have lines too weak to be placed on the most commonly used diagnostic diagram, [O iii]lambda 5007/H beta versus [N ii]lambda 6584/H alpha, despite the high signal-to-noise ratio of their spectra. This value increases to 35% in the [O iii]lambda 5007/[O ii]lambda 3727 diagram, owing to difficulties in line detection. Compared to optically selected narrow-line AGNs in the Sloan Digital Sky Survey, the BAT narrow-line AGNs have a higher rate of reddening/extinction, with H alpha/H beta > 5 (similar to 36%), indicating that hard X-ray selection more effectively detects obscured AGNs from the underlying AGN population. Finally, we present a subpopulation of AGNs that feature complex broad lines (34%, 250/743) or double-peaked narrow emission lines (2%, 17/743).
- ItemBASS. XXIX. The Near-infrared View of the Broad-line Region (BLR): The Effects of Obscuration in BLR Characterization(2022) Ricci, Federica ; Treister, Ezequiel ; Bauer, Franz E.; Mejía-Restrepo, Julian E. ; Koss, Michael J. ; den Brok, Jakob S. ; Baloković, Mislav ; Bär, Rudolf ; Bessiere, Patricia ; Caglar, Turgay ; Harrison, Fiona ; Ichikawa, Kohei ; Kakkad, Darshan; Lamperti, Isabella ; Mushotzky, Richard ; Oh, Kyuseok ; Powell, Meredith C. ; Privon, George C. ; Ricci, Claudio ; Riffel, Rogerio ; Rojas, Alejandra F. ; Sani, Eleonora ; Smith, Krista L. ; Stern, Daniel ; Trakhtenbrot, Benny ; Urry, C. Megan ; Veilleux, Sylvain
- ItemBASS. XXVI. DR2 Host Galaxy Stellar Velocity Dispersions(2022) Koss, Michael J.; Trakhtenbrot, Benny; Ricci, Claudio; Oh, Kyuseok; Bauer, Franz E.; Stern, Daniel; Caglar, Turgay; den Brok, Jakob S.; Mushotzky, Richard; Ricci, Federica; Mejia-Restrepo, Julian E.; Lamperti, Isabella; Treister, Ezequiel; Baer, Rudolf E.; Harrison, Fiona; Powell, Meredith C.; Privon, George C.; Riffel, Rogerio; Rojas, Alejandra F.; Schawinski, Kevin; Urry, C. MeganWe 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 ii H and K lambda 3969, 3934 and Mg I lambda 5175 region (3880-5550 angstrom) and the calcium triplet region (8350-8730 angstrom) from 642 spectra mainly from VLT/X-Shooter or Palomar/DoubleSpec. Our sample spans velocity dispersions of 40-360 km s(1), corresponding to 4-5 orders of magnitude in black hole mass (M (BH) = 10(5.5-9.6) M (circle dot)), bolometric luminosity (L (bol) similar to 10(42-46) erg s(-1)), and Eddington ratio (L/L (Edd) similar to 10(-5) to 2). For 281 AGN, our data and analysis provide the first published central velocity dispersions, including six AGN with low-mass black holes (M (BH) = 10(5.5-6.5) M (circle dot)), discovered thanks to high spectral resolution observations (sigma (inst) similar to 25 km s(-1)). 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 (z < 0.1) outside the Galactic plane ( divide b divide > 10 degrees). The BASS AGN have much higher velocity dispersions than the more numerous optically selected narrow-line AGN (i.e., similar to 150 versus similar to 100 km s(-1)) but are not biased toward the highest velocity dispersions of massive ellipticals (i.e., >250 km s(-1)). Despite sufficient spectral resolution to resolve the velocity dispersions associated with the bulges of small black holes (similar to 10(4-5) M (circle dot)), 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 similar to 100 BASS AGN.
- ItemBASS. XXVIII. Near-infrared Data Release 2: High-ionization and Broad Lines in Active Galactic Nuclei(2022) den Brok, Jakob S.; Koss, Michael J.; Trakhtenbrot, Benny; Stern, Daniel; Cantalupo, Sebastiano; Lamperti, Isabella; Ricci, Federica; Ricci, Claudio; Oh, Kyuseok; Bauer, Franz E.; Riffel, Rogerio; Rodriguez-Ardila, Alberto; Baer, Rudolf; Harrison, Fiona; Ichikawa, Kohei; Mejia-Restrepo, Julian E.; Mushotzky, Richard; Powell, Meredith C.; Boissay-Malaquin, Rozenn; Stalevski, Marko; Treister, Ezequiel; Urry, C. Megan; Veilleux, SylvainWe present the BAT AGN Spectroscopic Survey (BASS) Near-infrared Data Release 2 (DR2), a study of 168 nearby ((z) over bar = 0.04, z < 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 mu 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 chi > 100 eV). Comparing the emission of the [Si VI] lambda 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 III] lambda 5007 line (0.71 dex). We do not find any correlation between CL emission and the X-ray photon index Gamma. We find a clear trend of line blueshifts with increasing ionization potential in several CLs, such as [Si VI] lambda 1.9640, [Si X] lambda 1.4300, [S VIII] lambda 0.9915, and [S IX] lambda 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 alpha due to the presence of significant dust obscuration. In contrast, the broad Pa alpha and Pa beta emission lines are in agreement with the M-sigma 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.
- ItemBAT AGN Spectroscopic Survey (BASS) – VI. The ΓX–L/LEdd relation.(2017) Trakhtenbrot, Benny; Ricci, Claudio; Treister, Ezequiel; Koss, M.; Schawinski, Kevin; Mushotzky, Richard; Ueda, Yoshihiro; Veilleux, Sylvain; Lamperti, Isabella; Oh, Kyuseok; Stern, Daniel; Harrison, F.; Baloković, Mislav; Gehrels, Neil
- ItemBAT AGN Spectroscopic Survey - III : an observed link between AGN Eddington ratio and narrow-emission-line ratios.(2017) Oh, Kyuseok; Ricci, Claudio; Treister, Ezequiel; Schawinski, Kevin; Koss, M.; Trakhtenbrot, Benny; Lamperti, Isabella; Mushotzky, Richard; Veilleux, Sylvain; Berney, Simon; Crenshaw, D. Michael
- ItemBAT AGN Spectroscopic Survey - IV : near-Infrared Coronal Lines, Hidden Broad Lines, and Correlation with Hard X-ray emission.(2017) Lamperti, Isabella; Ricci, Claudio; Treister, Ezequiel; Koss, M.; Trakhtenbrot, Benny; Schawinski, Kevin; Oh, Kyuseok; Landt, Hermine; Riffel, Rogério; Rodríguez-Ardila, Alberto; Gehrels, Neil
- ItemBAT AGN Spectroscopic Survey - XIII. The nature of the most luminous obscured AGN in the low-redshift universe(2019) Bar, Rudolf E.; Trakhtenbrot, Benny; Oh, Kyuseok; Koss, Michael J.; Wong, Ivy; Ricci, Claudio; Schawinski, Kevin; Weigel, Anna K.; Sartori, Lia F.; Ichikawa, Kohei; Secrest, Nathan J.; Stern, Daniel; Pacucci, Fabio; Mushotzky, Richard; Powell, Meredith C.; Ricci, Federica; Sani, Eleonora; Smith, Krista L.; Harrison, Fiona A.; Lamperti, Isabella; Urry, C. MeganWe present a multiwavelength analysis of 28 of the most luminous low-redshift narrow-line, ultra-hard X-ray-selected active galactic nuclei (AGN) drawn from the 70-month Swift/BAT all-sky survey, with bolometric luminosities of log(L-bol/erg s(-1)) greater than or similar to 45.25. The broad goal of our study is to determine whether these objects have any distinctive properties, potentially setting them aside from lower luminosity obscured AGN in the local Universe. Our analysis relies on the first data release of the BAT AGN Spectroscopic Survey (BASS/DR1) and on dedicated observations with the VLT, Palomar, and Keck observatories. We find that the vast majority of our sources agree with commonly used AGN selection criteria which are based on emission line ratios and on mid-infrared colours. Our AGN are pre-dominantly hosted in massive galaxies (9.8 less than or similar to log (M-*/M-circle dot) less than or similar to 11.7); based on visual inspection of archival optical images, they appear to be mostly ellipticals. Otherwise, they do not have distinctive properties. Their radio luminosities, determined from publicly available survey data, show a large spread of almost four orders of magnitude- much broader than what is found for lower X-ray luminosity obscured AGN in BASS. Moreover, our sample shows no preferred combination of black hole masses (M-BH) and/or Eddington ratio (lambda(Edd)), covering 7.5 less than or similar to log (M-BH/M-circle dot) less than or similar to 10.3 and 0.01 less than or similar to lambda(Edd) less than or similar to 1. Based on the distribution of our sources in the lambda(Edd)-N-H plane, we conclude that our sample is consistent with a scenario where the amount of obscuring material along the line of sight is determined by radiation pressure exerted by the AGN on the dusty circumnuclear gas.
- ItemBAT AGN spectroscopic survey-II. X-ray emission and high-ionization optical emission lines.(2015) Berney, Simon; Ricci, Claudio; Treister, Ezequiel; Koss, M.; Trakhtenbrot, Benny; Lamperti, Isabella; Schawinski, Kevin; Crenshaw, D. Michael; Fischer, Travis; Gehrels, Neil
- ItemBAT AGN Spectroscopic Survey. I. Spectral Measurements, Derived Quantities, and AGN Demographics.(2017) Koss, M.; Ricci, Claudio; Treister, Ezequiel; Trakhtenbrot, Benny; Lamperti, Isabella; Oh, Kyuseok; Berney, Simon; Schawinski, Kevin; Baloković, Mislav; Baronchelli, Linda; Crenshaw, D. Michael
- ItemBAT AGN Spectroscopic Survey. VIII. Type 1 AGN with Massive Absorbing Columns(2018) Shimizu, T. Taro; Davies, Richard I.; Koss, Michael; Ricci, Claudio; Lamperti, Isabella; Oh, Kyuseok; Schawinski, Kevin; Trakhtenbrot, Benny; Burtscher, Leonard; Genzel, Reinhard; Lin, Ming-yi; Lutz, Dieter; Rosario, David; Sturm, Eckhard; T
- ItemBAT AGN Spectroscopic Survey. XX. Molecular Gas in Nearby Hard-X-Ray-selected AGN Galaxies(2021) Koss, Michael J. ; Strittmatter, Benjamin ; Lamperti, Isabella; Shimizu, Taro ; Trakhtenbrot, Benny ; Saintonge, Amelie ; Treister, Ezequiel ; Cicone, Claudia; Mushotzky, Richard ; Oh, Kyuseok; Ricci, Claudio ; Stern, Daniel ; Tasnim Ananna, Tonima ; Bauer, Franz Erik; Privon, George C. ; Bär, Rudolf ; De Breuck, Carlos; Harrison, Fiona ; Ichikawa, Kohei ; Powell, Meredith C. ; Rosario, David ; Sanders, David B. ; Schawinski, Kevin ; Shao, Li ; Urry, C. Megan ; Veilleux, SylvainWe present the host-galaxy molecular gas properties of a sample of 213 nearby (0.01.<.z.<.0.05) hard-X-rayselected active galactic nucleus (AGN) galaxies, drawn from the 70-month catalog of Swift's Burst Alert Telescope (BAT), with 200 new CO(2-1) line measurements obtained with the James Clerk Maxwell Telescope and the Atacama Pathfinder Experiment telescope. We find that AGN in massive galaxies (log(M*/M-circle dot) > 10.5) tend to have more molecular gas and higher gas fractions than inactive galaxies matched in stellar mass. When matched in star formation, we find AGN galaxies show no difference from inactive galaxies, with no evidence that AGN feedback affects the molecular gas. The higher molecular gas content is related to AGN galaxies hosting a population of gas-rich early types with an order of magnitude more molecular gas and a smaller fraction of quenched, passive galaxies (similar to 5% versus 49%) compared to inactive galaxies. The likelihood of a given galaxy hosting an AGN (L-bol > 10(44) erg s(-1)) increases by similar to 10-100 between a molecular gas mass of 10(8.7)M(circle dot) and 10(10.2)M(circle dot). AGN galaxies with a higher Eddington ratio (log(L/L-Edd) > -1.3) tend to have higher molecular gas masses and gas fractions. The log(N-H/cm(-2)) > 23.4) of AGN galaxies with higher column densities are associated with lower depletion timescales and may prefer hosts with more gas centrally concentrated in the bulge that may be more prone to quenching than galaxy-wide molecular gas. The significant average link of host-galaxy molecular gas supply to supermassive black hole (SMBH) growth may naturally lead to the general correlations found between SMBHs and their host galaxies, such as the correlations between SMBH mass and bulge properties, and the redshift evolution of star formation and SMBH growth.
- ItemNuSTAR RESOLVES THE FIRST DUAL AGN ABOVE 10 keV IN SWIFT J2028.5+2543(2016) Koss, Michael J.; Glidden, Ana; Baloković, Mislav; Stern, Daniel; Lamperti, Isabella; Assef, Roberto; Bauer, Franz Erik; Ballantyne, David; Boggs, Steven E.; Craig, William W.; Farrah, Duncan; Fürst, Felix; Gandhi, Poshak; Gehrels, Neil; Hailey, Charles J.; Harrison, Fiona A.; Markwardt, Craig; Masini, Alberto; Ricci, Claudio; Treister, Ezequiel; Koss, Michael J.; Glidden, Ana; Baloković, Mislav; Stern, Daniel; Lamperti, Isabella; Assef, Roberto; Bauer, Franz Erik; Ballantyne, David; Boggs, Steven E.; Craig, William W.; Farrah, Duncan; Fürst, Felix; Gandhi, Poshak; Gehrels, Neil; Hailey, Charles J.; Harrison, Fiona A.; Markwardt, Craig; Masini, Alberto; Ricci, Claudio; Treister, Ezequiel
- ItemThe close environments of accreting massive black holes are shaped by radiative feedback.(2017) Ricci, Claudio; Treister, Ezequiel; Trakhtenbrot, Benny; Koss, M.; Ueda, Yoshihiro; Schawinski, Kevin; Oh, Kyuseok; Lamperti, Isabella; Mushotzky, Richard; Ho, Luis C.; Weigel, Anna K.
- ItemThe CO(3–2)/CO(1–0) Luminosity Line Ratio in Nearby Star-forming Galaxies and Active Galactic Nuclei from xCOLD GASS, BASS, and SLUGS(2020) Lamperti, Isabella; Saintonge, Amélie; Koss, Michael; Viti, Serena; Wilson, Christine D.; He, Hao; Shimizu, T. Taro; Greve, Thomas R; Mushotzky, Richard; Treister, Ezequiel
- ItemThe NuSTAR Serendipitous Survey: Hunting for the Most Extreme Obscured AGN at >10 keV(2017) Lansbury, George B.; Bauer, Franz Erik; Treister, Ezequiel; Ricci, Claudio; Alexander, D. M.; Aird, J. A.; Gandhi, P.; Stern, Daniel.; Koss, M.; Lamperti, Isabella; Ajello, Marco