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California Polytechnic State University, San Luis Obispo

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Full-Text Articles in Physics

Space Telescope And Optical Reverberation Mapping Project. Viii. Time Variability Of Emission And Absorption In Ngc5548 Based On Modeling The Ultraviolet Spectrum, G. A. Kriss, G. De Rosa, J. Ely, B. M. Peterson, Vardha Nicola Bennert, Y. Zu Aug 2019

Space Telescope And Optical Reverberation Mapping Project. Viii. Time Variability Of Emission And Absorption In Ngc5548 Based On Modeling The Ultraviolet Spectrum, G. A. Kriss, G. De Rosa, J. Ely, B. M. Peterson, Vardha Nicola Bennert, Y. Zu

Physics

We model the ultraviolet spectra of the Seyfert 1 galaxy NGC 5548 obtained with the Hubble Space Telescope during the 6 month reverberation mapping campaign in 2014. Our model of the emission from NGC 5548 corrects for overlying absorption and deblends the individual emission lines. Using the modeled spectra, we measure the response to continuum variations for the deblended and absorption-corrected individual broad emission lines, the velocity-dependent profiles of Lyα and C iv, and the narrow and broad intrinsic absorption features. We find that the time lags for the corrected emission lines are comparable to those for the original ...


A Single Fast Radio Burst Localized To A Massive Galaxy At Cosmological Distance, K. W. Bannister, A. T. Deller, C. Phillips, J.-P. Macquart, Vardha Nicola Bennert, C. D. Wilson Aug 2019

A Single Fast Radio Burst Localized To A Massive Galaxy At Cosmological Distance, K. W. Bannister, A. T. Deller, C. Phillips, J.-P. Macquart, Vardha Nicola Bennert, C. D. Wilson

Physics

Fast radio bursts (FRBs) are brief radio emissions from distant astronomical sources. Some are known to repeat, but most are single bursts. Nonrepeating FRB observations have had insufficient positional accuracy to localize them to an individual host galaxy. We report the interferometric localization of the single-pulse FRB 180924 to a position 4 kiloparsecs from the center of a luminous galaxy at redshift 0.3214. The burst has not been observed to repeat. The properties of the burst and its host are markedly different from those of the only other accurately localized FRB source. The integrated electron column density along the ...


Jet-Driven Galaxy-Scale Gas Outflows In The Hyperluminous Quasar 3c 273, Bernd Husemann, Vardha Nicola Bennert, Knud Jahnke, Timothy A. Davis, Jong-Hak Woo, Julia Scharwächter, Andreas Schulze, Massimo Gaspari, Martin A. Zwaan Jul 2019

Jet-Driven Galaxy-Scale Gas Outflows In The Hyperluminous Quasar 3c 273, Bernd Husemann, Vardha Nicola Bennert, Knud Jahnke, Timothy A. Davis, Jong-Hak Woo, Julia Scharwächter, Andreas Schulze, Massimo Gaspari, Martin A. Zwaan

Physics

We present an unprecedented view of the morphology and kinematics of the extended narrow-line region (ENLR) and molecular gas around the prototypical hyperluminous quasar 3C 273 (L bol ~ 1047 erg s−1 at z = 0.158) based on VLT-MUSE optical 3D spectroscopy and ALMA observations. We find the following: (1) the ENLR size of 12.1 ± 0.2 kpc implies a smooth continuation of the size–luminosity relation out to large radii or a much larger break radius as previously proposed. (2) The kinematically disturbed ionized gas with line splits reaching 1000 km s−1 out to 6.1 ...


Agn Photoionization Of Gas In Companion Galaxies As A Probe Of Agn Radiation In Time And Direction, William C. Keel, Vardha Nicola Bennert, Anna Pancoast, Chelsea E. Harris, Anna Nierenberg, S. Drew Chojnowski, Alexei V. Moiseev, Dmitry V. Oparin, Chris J. Lintott, Kevin Schawinski, Graham Mitchell, Claude Cornen Mar 2019

Agn Photoionization Of Gas In Companion Galaxies As A Probe Of Agn Radiation In Time And Direction, William C. Keel, Vardha Nicola Bennert, Anna Pancoast, Chelsea E. Harris, Anna Nierenberg, S. Drew Chojnowski, Alexei V. Moiseev, Dmitry V. Oparin, Chris J. Lintott, Kevin Schawinski, Graham Mitchell, Claude Cornen

Physics

We consider active galactic nucleus (AGN) photoionization of gas in companion galaxies (cross-ionization) as a way to sample the intensity of AGN radiation in both direction and time, independent of the gas properties of the AGN host galaxies. From an initial set of 212 AGN+companion systems, identified with the help of Galaxy Zoo participants, we obtained long-slit optical spectra of 32 pairs that were a priori likely to show cross-ionization based on projected separation or angular extent of the companion. From emission-line ratios, 10 of these systems are candidates for cross-ionization, roughly the fraction expected if most AGNs have ...


The Lick Agn Monitoring Project 2011: Photometric Light Curves, Anna Pancoast, Andreas Skielboe, Liuyi Pei, Vardha Nicola Bennert, Jong-Hak Woo Jan 2019

The Lick Agn Monitoring Project 2011: Photometric Light Curves, Anna Pancoast, Andreas Skielboe, Liuyi Pei, Vardha Nicola Bennert, Jong-Hak Woo

Physics

In Spring 2011, the Lick AGN Monitoring Project observed a sample of 15 bright, nearby Seyfert 1 galaxies in the V band as part of a reverberation mapping campaign. The observations were taken at six ground-based telescopes, including the West Mountain Observatory 0.91 m telescope, the 0.76 m Katzman Automatic Imaging Telescope, 0.6 m Super-LOTIS at Kitt Peak, the Palomar 60 inch telescope, and the 2 m Faulkes telescopes North and South. The V-band light curves measure the continuum variability of our sample of Seyferts on an almost daily cadence for 2–3 months. We use ...


Memory In A Contact Line, Charity Lizardo, Esmeralda Orozco, Audrey Profeta, Nathan C. Keim Jan 2019

Memory In A Contact Line, Charity Lizardo, Esmeralda Orozco, Audrey Profeta, Nathan C. Keim

STAR (STEM Teacher and Researcher) Presentations

We study the behavior of the liquid-solid-vapor contact line of water held in a narrow gap between two plates. A syringe pump injects and withdraws a constant, small volume of the water, driving the contact line back and forth repeatedly and changing its shape. We take photos of the contact line after each cycle. Comparing subsequent images to each other, we find that after several cycles the contact line reaches one of two steady states: a reversible steady state, where the shape is not changing, or a fluctuating steady state, where the shape continues to change slightly. Experiments on acrylic ...


Detrital Zircon Geochronology And Evolution Of The Nacimiento Block Late Mesozoic Forearc Basin, Central California Coast, Scott Johnston, Andrew R.C. Kylander-Clark, Alan D. Chapman Dec 2018

Detrital Zircon Geochronology And Evolution Of The Nacimiento Block Late Mesozoic Forearc Basin, Central California Coast, Scott Johnston, Andrew R.C. Kylander-Clark, Alan D. Chapman

Physics

Forearc basins are first-order products of convergent-margin tectonics, and their sedimentary deposits offer unique perspectives on coeval evolution of adjacent arcs and subduction complexes. New detrital zircon U-Pb geochronologic data from 23 sandstones and 11 individual conglomerate clasts sampled from forearc basin strata of the Nacimiento block, an enigmatic stretch of the Cordilleran forearc exposed along the central California coast, place constraints on models for forearc deformation during evolution of the archetypical Cordilleran Mesozoic margin. Deposition and provenance of the Nacimiento forearc developed in three stages: (1) Late Jurassic– Valanginian deposition of lower Nacimiento forearc strata with zircon derived from ...


Geologic Map And Structural Development Of The Noerthernmost Sur-Nacimiento Fault Zone, Central California Coast, Scott M. Johnston, John S. Singleton, Alan D. Chapman, Gabriella Murray Dec 2018

Geologic Map And Structural Development Of The Noerthernmost Sur-Nacimiento Fault Zone, Central California Coast, Scott M. Johnston, John S. Singleton, Alan D. Chapman, Gabriella Murray

Physics

The Sur-Nacimiento fault exposed along the central California coast (United States) juxtaposes the Salinian block arc against the Nacimiento block accretionary complex, cuts out the majority of the forearc basin and western arc, and requires a minimum of 150 km of orogen-normal crustal excision within the Mesozoic California convergent margin. Despite this significant strain, the kinematic evolution of the Sur-Nacimiento fault remains poorly understood, with diverse hypotheses suggesting sinistral, dextral, thrust, or normal displacement along the fault. This Late Cretaceous–Paleogene strain history is complicated by the location of the fault within a belt of subparallel faults that have accommodated ...


Revealing The Broad Line Region Of Ngc 1275: The Relationship To Jet Power, Brian Punsly, Paola Marziani, Vardha Nicola Bennert, Hiroshi Nagai, Mark A. Gurwell Dec 2018

Revealing The Broad Line Region Of Ngc 1275: The Relationship To Jet Power, Brian Punsly, Paola Marziani, Vardha Nicola Bennert, Hiroshi Nagai, Mark A. Gurwell

Physics

NGC 1275 is one of the most conspicuous active galactic nuclei (AGN) in the local universe. The radio jet currently emits a flux density of ~10 Jy at ~1 mm wavelengths, down from the historic high of ~65 Jy in 1980. Yet, the nature of the AGN in NGC 1275 is still controversial. It has been debated whether this is a broad emission line (BEL) Seyfert galaxy, an obscured Seyfert galaxy, a narrow line radio galaxy, or a BL Lac object. We clearly demonstrate a persistent Hβ BEL over the last 35 yr with a full width at half ...


Studying The [O Iii]Λ5007 Å Emission-Line Width In A Sample Of ∼ 80 Local Active Galaxies: A Surrogate For Σ⋆?, Vardha Nicola Bennert, Donald Loveland, Edward Donohue, Maren Cosens, Sean Lewis, S. Komossa, Tommaso Treu, Matthew A. Malkan, Nathan Milgram, Kelsi Flatland, Matthew W. Auger, Daesong Park, Mariana S. Lazarova Nov 2018

Studying The [O Iii]Λ5007 Å Emission-Line Width In A Sample Of ∼ 80 Local Active Galaxies: A Surrogate For Σ⋆?, Vardha Nicola Bennert, Donald Loveland, Edward Donohue, Maren Cosens, Sean Lewis, S. Komossa, Tommaso Treu, Matthew A. Malkan, Nathan Milgram, Kelsi Flatland, Matthew W. Auger, Daesong Park, Mariana S. Lazarova

Physics

For a sample of ∼ 80 local (0.02 ≤ z" role="presentation">z ≤ 0.1) Seyfert-1 galaxies with high-quality long-slit Keck spectra and spatially resolved stellar-velocity dispersion (σ) measurements, we study the profile of the [O iii]λ5007 Å emission line to test the validity of using its width as a surrogate for σ. Such an approach has often been used in the literature, since it is difficult to measure σ for type-1 active galactic nuclei (AGNs) due to the AGN continuum outshining the stellar-absorption lines. Fitting the [O iii] line with a single Gaussian or Gauss–Hermite polynomials overestimates σ ...


Assessment Of Surface Wind Datasets For Estimating Offshore Wind Energy Along The Central California Coast, Yi-Hui Wang, Ryan K. Walter, Crow White, Hayley Farr, Benjamin I. Ruttenberg Oct 2018

Assessment Of Surface Wind Datasets For Estimating Offshore Wind Energy Along The Central California Coast, Yi-Hui Wang, Ryan K. Walter, Crow White, Hayley Farr, Benjamin I. Ruttenberg

Physics

In the United States, Central California has gained significant interest in offshore wind energy due to its strong winds and proximity to existing grid connections. This study provides a comprehensive evaluation of near-surface wind datasets in this region, including satellite-based observations (QuikSCAT, ASCAT, and CCMP V2.0), reanalysis (NARR and MERRA), and regional atmospheric models (WRF and WIND Toolkit). This work highlights spatiotemporal variations in the performance of the respective datasets in relation to in-situ buoy measurements using error metrics over both seasonal and diurnal time scales. The two scatterometers(QuikSCAT and ASCAT) showed the best overall performance, albeit with ...


The Lick Agn Monitoring Project 2011: Dynamical Modeling Of The Broad-Line Region, Peter R. Williams, Anna Pancoast, Tommaso Treu, Brendon J. Brewer, Vardha N. Bennert, Jong-Hak Woo Oct 2018

The Lick Agn Monitoring Project 2011: Dynamical Modeling Of The Broad-Line Region, Peter R. Williams, Anna Pancoast, Tommaso Treu, Brendon J. Brewer, Vardha N. Bennert, Jong-Hak Woo

Physics

We present models of the Hβ-emitting broad-line region (BLR) in seven Seyfert 1 galaxies from the Lick AGN Monitoring Project 2011 sample, drawing inferences on the BLR structure and dynamics as well as the mass of the central supermassive black hole. We find that the BLR is generally a thick disk, viewed close to face-on, with preferential emission back toward the ionizing source. The dynamics in our sample range from near-circular elliptical orbits to inflowing or outflowing trajectories. We measure black hole masses of for PG 1310−108, for Mrk 50, for Mrk 141, for Mrk 279, for ...


Reversible Motion In A Contact Line, Audrey Profeta, Esmeralda Orozco, Juan A. Ortiz Salazar, Dani Medina, Nathan C. Keim Sep 2018

Reversible Motion In A Contact Line, Audrey Profeta, Esmeralda Orozco, Juan A. Ortiz Salazar, Dani Medina, Nathan C. Keim

STAR (STEM Teacher and Researcher) Presentations

When a body of liquid sits on a surface, an irregular border between the wet and dry regions of the surface exists, called the contact line. Driving this contact line back and forth repeatedly can change its shape.We use a syringe pump to cyclically infuse and withdraw a predetermined volume of water, and take photos of the contact line after each cycle. Comparing these images to each other determines if the contact line is returning to the same shape. We find that below a critical value of infused volume, after many cycles the contact line reaches a steady state ...


Hydrodynamics In A Shallow Seasonally Low-Inflow Estuary Following Eelgrass Collapse, Ryan K. Walter, Edwin J. Rainville, Jennifer K. O'Leary Aug 2018

Hydrodynamics In A Shallow Seasonally Low-Inflow Estuary Following Eelgrass Collapse, Ryan K. Walter, Edwin J. Rainville, Jennifer K. O'Leary

Physics

Hydrodynamics play a critical role in mediating biological and ecological processes and can have major impacts on the distribution of habitat-forming species. Low-inflow estuaries are widespread in arid regions and during the dry season in Mediterranean climates. There is a growing need to evaluate dynamics and exchange processes in these systems and the resultant ecological linkages. We investigate the role that hydrodynamics play in shaping environmental gradients in a short and seasonally low-inflow estuary located along the central California coast. Since 2007, eelgrass meadows in Morro Bay have declined by more than 90%, representing the collapse of the major biogenic ...


Anisotropic Conductive Adhesives For Interdigitated Back Contact (Ibc) Silicon Solar Cells, Katherine M. Lohmuste, Manuel Schnabel, Maikel F.A.M. Van Hest Aug 2018

Anisotropic Conductive Adhesives For Interdigitated Back Contact (Ibc) Silicon Solar Cells, Katherine M. Lohmuste, Manuel Schnabel, Maikel F.A.M. Van Hest

STAR (STEM Teacher and Researcher) Presentations

The current manufacturing process for solar panels using interdigitated back contact (IBC) silicon solar cells involves a multi-step metallization and interconnection process in which a substantial amount of silver is used. This work focuses on a new process using conductive adhesives (CA) which would increase efficiency and lower cost through a one-step metallization and interconnection process that combines with encapsulation using little silver and only requiring metal patterning on the back sheet or back glass. It would also not require direct metallization of the silicon, which would result in fewer defects, while increasing voltage and therefore efficiency. Silver-coated Poly(Methyl ...


Calibration And Limitations Of The Mg Ii Line-Based Black Hole Masses, Jong-Hak Woo, Huynh Anh N. Le, Marios Karouzos, Dawoo Park, Daesong Park, Matthew A. Malkan, Tommaso Treu, Vardha Nicola Bennert Jun 2018

Calibration And Limitations Of The Mg Ii Line-Based Black Hole Masses, Jong-Hak Woo, Huynh Anh N. Le, Marios Karouzos, Dawoo Park, Daesong Park, Matthew A. Malkan, Tommaso Treu, Vardha Nicola Bennert

Physics

We present single-epoch black hole mass () calibrations based on the rest-frame ultraviolet (UV) and optical measurements of Mg ii 2798 Å and Hβ 4861 Å lines and the active galactic nucleus (AGN) continuum, using a sample of 52 moderate-luminosity AGNs at z ~ 0.4 and z ~ 0.6 with high-quality Keck spectra. We combine this sample with a large number of luminous AGNs from the Sloan Digital Sky Survey to increase the dynamic range for a better comparison of UV and optical velocity and luminosity measurements. With respect to the reference based on the line dispersion of Hβ ...


Influence Of Internal Bores On Larval Fish Abundance And Community Composition, Patrick J. Phelan, John Steinbeck, Ryan K. Walter Mar 2018

Influence Of Internal Bores On Larval Fish Abundance And Community Composition, Patrick J. Phelan, John Steinbeck, Ryan K. Walter

Physics

A persistent semidiurnal internal tidal bore feature occurs at the head of the Monterey Bay Submarine Canyon and drives regular intrusions of cold, subthermocline waters onto the adjacent shelf. In this study, we examine the influence of this internal tidal bore feature on the larval fish community using over a year of periodic larval fish samples collected coincidently with physical measurements. Larval samples were categorized into one of two water mass periods: a “warm period” representative of shallow coastal shelf waters and a “cold period” characteristics of colder waters present during internal bore forcing. Using multivariate statistical methods, we show ...


Stability Of The Broad-Line Region Geometry And Dynamics In Arp 151 Over Seven Years, A. Pancoast, A. J. Barth, K. Horne, T. Treu, Vardha N. Bennert, H. Winkler Mar 2018

Stability Of The Broad-Line Region Geometry And Dynamics In Arp 151 Over Seven Years, A. Pancoast, A. J. Barth, K. Horne, T. Treu, Vardha N. Bennert, H. Winkler

Physics

The Seyfert 1 galaxy Arp 151 was monitored as part of three reverberation mapping campaigns spanning 2008–2015. We present modeling of these velocity-resolved reverberation mapping data sets using a geometric and dynamical model for the broad-line region (BLR). By modeling each of the three data sets independently, we infer the evolution of the BLR structure in Arp 151 over a total of 7 yr and constrain the systematic uncertainties in nonvarying parameters such as the black hole mass. We find that the BLR geometry of a thick disk viewed close to face-on is stable over this time, although the ...


Coastal Upwelling Seasonality And Variability Of Temperature And Chlorophyll In A Small Coastal Embayment, Ryan K. Walter, Kevin Armenta, Brandon Shearer, Ian C. Robbins, John Steinbeck Jan 2018

Coastal Upwelling Seasonality And Variability Of Temperature And Chlorophyll In A Small Coastal Embayment, Ryan K. Walter, Kevin Armenta, Brandon Shearer, Ian C. Robbins, John Steinbeck

Physics

While the seasonality of wind-driven coastal upwelling in eastern boundary upwelling systems has long been established, many studies describe two distinct seasons (upwelling and non-upwelling), a generalized framework that does not capture details relevant to marine ecosystems. In this contribution, we present a more detailed description of the annual cycle and upwelling seasonality for an understudied location along the central California coast. Using both the mean monthly upwelling favorable wind stress and the monthly standard deviation, we define the following seasons (contiguous months) and a transitional period (non-contiguous months): “Winter Storms” season (Dec-Jan-Feb), “Upwelling Transition” period (Mar and Jun), “Peak ...


Resistance Temperature Detectors In A Cryostat Refrigeration System, Kirsten Marie Manahan, Alice Callen Jan 2018

Resistance Temperature Detectors In A Cryostat Refrigeration System, Kirsten Marie Manahan, Alice Callen

STAR (STEM Teacher and Researcher) Presentations

The Large Synoptic Survey Telescope (LSST) is a ground-based telescope that will survey the Southern sky every few nights. Located in the telescope will be a 3.2 gigapixel digital camera. To ensure proper instrumentation of the camera, there must be a monitored stable temperature. As part of my research, I assembled resistance temperature detectors and tested them to verify their reliability in measuring temperature in the camera’s cryostat refrigeration cooling system. Resistance temperature detectors function by the principle of thermal resistivity, in which their electrical resistances vary as temperature varies. Through testing, I was able to determine whether ...


X-Ray Spectroscopy Of Nio And Nanodiamond At Ssrl, Jackson Earl Jan 2018

X-Ray Spectroscopy Of Nio And Nanodiamond At Ssrl, Jackson Earl

STAR (STEM Teacher and Researcher) Presentations

The first aspect of this research project focuses on investigating the surface chemistry of high pressure high temperature (HPHT) nanodiamond by using X-ray spectroscopy techniques at the Stanford Synchrotron Radiation Lightsource (SSRL). HPHT nanodiamond is being examined as a biosensing tool for electric field detection based on the fluorescent nitrogen vacancy center hosted within diamond. With use of the transition edge spectrometer (TES), a state-of-the-art X-ray fluorescence detector, we are able to probe the surface and bulk properties of diamond. Preliminary work using density functional theory (DFT) has been done, offering insight into ground state energies and electronic structure. DFT ...


H0licow Vii: Cosmic Evolution Of The Correlation Between Black Hole Mass And Host Galaxy Luminosity, Xuheng Ding, Tommaso Treu, Sherry H. Suyu, Kenneth C. Wong, Takahiro Morishita, Daesong Park, Dominique Sluse, Matthew W. Auger, Adriano Agnello, Vardha Nicola Bennert, Thomas E. Collett Nov 2017

H0licow Vii: Cosmic Evolution Of The Correlation Between Black Hole Mass And Host Galaxy Luminosity, Xuheng Ding, Tommaso Treu, Sherry H. Suyu, Kenneth C. Wong, Takahiro Morishita, Daesong Park, Dominique Sluse, Matthew W. Auger, Adriano Agnello, Vardha Nicola Bennert, Thomas E. Collett

Physics

Strongly lensed active galactic nuclei (AGN) provide a unique opportunity to make progress in the study of the evolution of the correlation between the mass of supermassive black holes (MBH⁠⁠) and their host galaxy luminosity (Lhost). We demonstrate the power of lensing by analysing two systems for which state-of-the-art lens modelling techniques have been applied to deep Hubble Space Telescope imaging data. We use (i) the reconstructed images to infer the total and bulge luminosity of the host and (ii) published broad-line spectroscopy to estimate MBH using the so-called virial method. We then enlarge our sample with ...


Discovery And Follow-Up Observations Of The Young Type Ia Supernova 2016coj, Weikang Zheng, Alexei V. Filippenko, Jon Mauerhan, Melissa L. Graham, Vardha Nicola Bennert, Xiaofeng Wang May 2017

Discovery And Follow-Up Observations Of The Young Type Ia Supernova 2016coj, Weikang Zheng, Alexei V. Filippenko, Jon Mauerhan, Melissa L. Graham, Vardha Nicola Bennert, Xiaofeng Wang

Physics

The Type Ia supernova (SN Ia) 2016coj in NGC 4125 (redshift z = 0.00452 ± 0.00006) was discovered by the Lick Observatory Supernova Search 4.9 days after the fitted first-light time (FFLT; 11.1 days before B-band maximum). Our first detection (prediscovery) is merely 0.6 ± 0.5 days after the FFLT, making SN 2016coj one of the earliest known detections of an SN Ia. A spectrum was taken only 3.7 hr after discovery (5.0 days after the FFLT) and classified as a normal SN Ia. We performed high-quality photometry, low- and high-resolution spectroscopy, and spectropolarimetry ...


Development, Implementation, And Validation Of A California Coastal Ocean Modeling, Data Assimilation, And Forecasting System, Yi Chao, John D. Farrara, Hongchun Zhang, Kevin Armenta, Luca Centurioni, Francisco Chavez, James B. Girton, Dan Rudnick, Ryan K. Walter Apr 2017

Development, Implementation, And Validation Of A California Coastal Ocean Modeling, Data Assimilation, And Forecasting System, Yi Chao, John D. Farrara, Hongchun Zhang, Kevin Armenta, Luca Centurioni, Francisco Chavez, James B. Girton, Dan Rudnick, Ryan K. Walter

Physics

A three-dimensional, near real-time data-assimilative modeling system for the California coastal ocean is presented. The system consists of a Regional Ocean Modeling System (ROMS) forced by the North American Mesoscale Forecast System (NAM). The ocean model has a horizontal resolution of approximately three kilometers and utilizes a multi-scale three-dimensional variational (3DVAR) data assimilation methodology. The system is run in near real-time to produce a nowcast every six hours and a 72-hour forecast every day. The performance of this nowcast system is presented using results from a six-year period of 2009–2015.

The ROMS results are first compared with the assimilated ...


Extending The Calibration Of C Iv-Based Single-Epoch Black Hole Mass Estimators For Active Galactic Nuclei, Daeseong Park, Aaron J. Barth, Jong-Hak Woo, Matthew A. Malkan, Tommaso Treu, Vardha Nicola Bennert, Roberto J. Assef, Anna Pancoast Apr 2017

Extending The Calibration Of C Iv-Based Single-Epoch Black Hole Mass Estimators For Active Galactic Nuclei, Daeseong Park, Aaron J. Barth, Jong-Hak Woo, Matthew A. Malkan, Tommaso Treu, Vardha Nicola Bennert, Roberto J. Assef, Anna Pancoast

Physics

We provide an updated calibration of C iv broad emission line–based single-epoch (SE) black hole (BH) mass estimators for active galactic nuclei (AGNs) using new data for six reverberation-mapped AGNs at redshift with BH masses (bolometric luminosities) in the range ( erg s−1). New rest-frame UV-to-optical spectra covering 1150–5700 Å for the six AGNs were obtained with the Hubble Space Telescope (HST). Multicomponent spectral decompositions of the HST spectra were used to measure SE emission-line widths for the C iv, Mg ii, and Hβ lines, as well as continuum luminosities in the spectral region around each line ...


Space Telescope And Optical Reverberation Mapping Project. V. Optical Spectroscopic Campaign And Emission-Line Analysis For Ngc 5548, L. Pei, M. M. Fausnaugh, A. J. Barth, B. M. Peterson, Vardha Nicola Bennert, Y. Zu Mar 2017

Space Telescope And Optical Reverberation Mapping Project. V. Optical Spectroscopic Campaign And Emission-Line Analysis For Ngc 5548, L. Pei, M. M. Fausnaugh, A. J. Barth, B. M. Peterson, Vardha Nicola Bennert, Y. Zu

Physics

We present the results of an optical spectroscopic monitoring program targeting NGC 5548 as part of a larger multiwavelength reverberation mapping campaign. The campaign spanned 6 months and achieved an almost daily cadence with observations from five ground-based telescopes. The Hβ and He ii λ4686 broad emission-line light curves lag that of the 5100 Å optical continuum by and , respectively. The Hβ lag relative to the 1158 Å ultraviolet continuum light curve measured by the Hubble Space Telescope is ~50% longer than that measured against the optical continuum, and the lag difference is consistent with the observed ...


Fading Agn Candidates: Agn Histories And Outflow Signatures, William C. Keel, Chris J. Lintott, W. Peter Maksym, Vardha N. Bennert, S. Drew Chojnowski, Alexei Moiseev, Aleksandrina Smirnova, Kevin Schawinski, Lia F. Sartori, C. Megan Urry, Anna Pancoast, Mischa Schirmer, Bryan Scott, Charles Grant Showley, Kelsi Flatland Feb 2017

Fading Agn Candidates: Agn Histories And Outflow Signatures, William C. Keel, Chris J. Lintott, W. Peter Maksym, Vardha N. Bennert, S. Drew Chojnowski, Alexei Moiseev, Aleksandrina Smirnova, Kevin Schawinski, Lia F. Sartori, C. Megan Urry, Anna Pancoast, Mischa Schirmer, Bryan Scott, Charles Grant Showley, Kelsi Flatland

Physics

We consider the energy budgets and radiative history of eight fading active galactic nuclei (AGNs), identified from an energy shortfall between the requirements to ionize very extended (radius > 10 kpc) ionized clouds and the luminosity of the nucleus as we view it directly. All show evidence of significant fading on timescales of ≈50,000 yr. We explore the use of minimum ionizing luminosity Qion derived from photoionization balance in the brightest pixels in Hα at each projected radius. Tests using presumably constant Palomar–Green QSOs, and one of our targets with detailed photoionization modeling, suggest that we can ...


Local Diurnal Wind‐Driven Variability And Upwelling In A Small Coastal Embayment, Ryan K. Walter, Emma C. Reid, Kristen A. Davis, Kevin Armenta, Kevin Merhoff, Nicholas J. Nidzieko Jan 2017

Local Diurnal Wind‐Driven Variability And Upwelling In A Small Coastal Embayment, Ryan K. Walter, Emma C. Reid, Kristen A. Davis, Kevin Armenta, Kevin Merhoff, Nicholas J. Nidzieko

Physics

The oceanic response to high‐frequency local diurnal wind forcing is examined in a small coastal embayment located along an understudied stretch of the central California coast. We show that local diurnal wind forcing is the dominant control on nearshore temperature variability and circulation patterns. A complex empirical orthogonal function (CEOF) analysis of velocities in San Luis Obispo Bay reveals that the first‐mode CEOF amplitude time series, which accounts for 47.9% of the variance, is significantly coherent with the local wind signal at the diurnal frequency and aligns with periods of weak and strong wind forcing. The diurnal ...


Large-Scale Outflows In Luminous Qsos Revisited: The Impact Of Beam Smearing On Agn Feedback Efficiencies, Bernd Husemann, Julia Scharwächter, Vardha N. Bennert, V. Manieri, Jong-Hak Woo, Darshan Kakkad Oct 2016

Large-Scale Outflows In Luminous Qsos Revisited: The Impact Of Beam Smearing On Agn Feedback Efficiencies, Bernd Husemann, Julia Scharwächter, Vardha N. Bennert, V. Manieri, Jong-Hak Woo, Darshan Kakkad

Physics

Context. Feedback from active galactic nuclei (AGN) is thought to play an important role in quenching star formation in galaxies. However, the efficiency with which AGN dissipate their radiative energy into the ambient medium remains strongly debated.

Aims. Enormous observational efforts have been made to constrain the energetics of AGN feedback by mapping the kinematics of the ionized gas on kpc scale. We study how the observed kinematics and inferred energetics are affected by beam smearing of a bright unresolved narrow-line region (NLR) due to seeing.

Methods. We re-analyse optical integral-field spectroscopy of a sample of twelve luminous unobscured quasi-stellar ...


Optimizing The Telescope Assembly Alignment Simulator For Sofia, Zoe E. Sharp, Alex Quyenvo, Jennifer Briggs, Brian Eney Oct 2016

Optimizing The Telescope Assembly Alignment Simulator For Sofia, Zoe E. Sharp, Alex Quyenvo, Jennifer Briggs, Brian Eney

STAR (STEM Teacher and Researcher) Presentations

The Stratospheric Observatory for Infrared Astronomy (SOFIA) conducts research on a modified Boeing 747sp aircraft. By using a variety of infrared science instruments mounted on a 2.7 meter telescope, researchers can make discoveries about the galactic center, star formation, and various topics associated with a deeper understanding of our universe. To efficiently collect data through the SOFIA instruments, the instruments must be tested and prepared prior to being placed on the aircraft. Therefore, with the use of the Telescope Assembly Alignment Simulator (TAAS), researchers can design and construct improvements needed for these instruments to efficiently perform while in flight ...