Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- CD (4)
- Galaxies: clusters: intracluster medium (4)
- Galaxies: elliptical and lenticular (4)
- X-rays: galaxies: clusters (4)
- Gravitational lensing (3)
-
- Asteroids (2)
- Dynamics (2)
- Galaxies: clusters: general (2)
- Radio continuum: galaxies (2)
- Ultraviolet: galaxies (2)
- Binaries: close (1)
- Binaries: eclipsing (1)
- Binaries: general (1)
- Binaries: spectroscopic (1)
- Comets: general (1)
- Cosmology: observations (1)
- Distance scale (1)
- Galaxies: Starburst (1)
- Galaxies: evolution (1)
- Galaxies: individual (FOV J0743+1553) (1)
- Galaxies: luminosity function (1)
- Galaxies: spiral (1)
- Instrumentation: interferometers (1)
- Mass function (1)
- Methods: Data analysis (1)
- Methods: Observational (1)
- Orbit determination (1)
- Planets and satellites: Atmospheres (1)
- Planets and satellites: Physical evolution (1)
- Planets and satellites: Terrestrial planets (1)
Articles 1 - 14 of 14
Full-Text Articles in Physical Sciences and Mathematics
Lower Atmosphere And Pressure Evolution On Pluto From Ground-Based Stellar Occultations, 1988-2016, E. Meza, B. Sicardy, M. Assafin, J. L. Ortiz
Lower Atmosphere And Pressure Evolution On Pluto From Ground-Based Stellar Occultations, 1988-2016, E. Meza, B. Sicardy, M. Assafin, J. L. Ortiz
University Faculty Publications and Creative Works
Context. The tenuous nitrogen (N2) atmosphere on Pluto undergoes strong seasonal effects due to high obliquity and orbital eccentricity, and has recently (July 2015) been observed by the New Horizons spacecraft. Aims. The main goals of this study are (i) to construct a well calibrated record of the seasonal evolution of surface pressure on Pluto and (ii) to constrain the structure of the lower atmosphere using a central flash observed in 2015. Methods. Eleven stellar occultations by Pluto observed between 2002 and 2016 are used to retrieve atmospheric profiles (density, pressure, temperature) between altitude levels of ∼5 and ∼380 km …
The First Post-Kepler Brightness Dips Of Kic 8462852, Tabetha S. Boyajian, Roi Alonso, Alex Ammerman, David Armstrong
The First Post-Kepler Brightness Dips Of Kic 8462852, Tabetha S. Boyajian, Roi Alonso, Alex Ammerman, David Armstrong
University Faculty Publications and Creative Works
We present a photometric detection of the first brightness dips of the unique variable star KIC 8462852 since the end of the Kepler space mission in 2013 May. Our regular photometric surveillance started in 2015 October, and a sequence of dipping began in 2017 May continuing on through the end of 2017, when the star was no longer visible from Earth. We distinguish four main 1%-2.5% dips, named "Elsie," "Celeste," "Skara Brae," and "Angkor," which persist on timescales from several days to weeks. Our main results so far are as follows: (i) there are no apparent changes of the stellar …
Prediction Of A Red Nova Outburst In Kic 9832227, Lawrence A. Molnar, Daniel M. Van Noord, Karen Kinemuchi, Jason P. Smolinski
Prediction Of A Red Nova Outburst In Kic 9832227, Lawrence A. Molnar, Daniel M. Van Noord, Karen Kinemuchi, Jason P. Smolinski
University Faculty Publications and Creative Works
We present the first identification of a candidate precursor for an imminent red nova. Our prediction is based on the example of the precursor to the red nova V1309 Sco, which was retrospectively found to be a contact binary with an exponentially decreasing period. We explore the use of this distinctive timing signature to identify precursors, developing the observational and analysis steps needed. We estimate that our Galaxy has roughly 1-10 observable precursors. Specifically, we lay out the observational case for KIC 9832227, which we identified as a tentative candidate two years ago (Molnar et al. 2015, AAS Meeting #225 …
The Small Binary Asteroid (939) Isberga, B. Carry, A. Matter, P. Scheirich, P. Pravec
The Small Binary Asteroid (939) Isberga, B. Carry, A. Matter, P. Scheirich, P. Pravec
University Faculty Publications and Creative Works
In understanding the composition and internal structure of asteroids, their density is perhaps the most diagnostic quantity. We aim here at characterizing the surface composition, mutual orbit, size, mass, and density of the small main-belt binary asteroid (939) Isberga. For that, we conduct a suite of multi-technique observations, including optical lightcurves over many epochs, near-infrared spectroscopy, and interferometry in the thermal infrared. We develop a simple geometric model of binary systems to analyze the interferometric data in combination with the results of the lightcurve modeling. From spectroscopy, we classify Ibserga as a Sq-type asteroid, consistent with the albedo of 0.14-0.06+0.09 …
Defining The Flora Family: Orbital Properties, Reflectance Properties And Age, Melissa J. Dykhuis, Lawrence Molnar, Samuel J. Van Kooten, Richard Greenberg
Defining The Flora Family: Orbital Properties, Reflectance Properties And Age, Melissa J. Dykhuis, Lawrence Molnar, Samuel J. Van Kooten, Richard Greenberg
University Faculty Publications and Creative Works
The Flora family resides in the densely populated inner main belt, bounded in semimajor axis by the ν6 secular resonance and the Jupiter 3:1 mean motion resonance. The presence of several large families that overlap dynamically with the Floras (e.g., the Vesta, Baptistina, and Nysa-Polana families), and the removal of a significant fraction of Floras via the nearby ν6 resonance complicates the Flora family's distinction in both proper orbital elements and reflectance properties. Here we use orbital information from the Asteroids Dynamic Site (AstDyS), color information from the Sloan Digital Sky Survey (SDSS), and albedo information from the Wide-field Infrared …
Star Formation And Uv Colors Of The Brightest Cluster Galaxies In The Representative Xmm-Newton Cluster Structure Survey, Megan Donahue, Seth Bruch, Emily Wang, G. Mark Voit
Star Formation And Uv Colors Of The Brightest Cluster Galaxies In The Representative Xmm-Newton Cluster Structure Survey, Megan Donahue, Seth Bruch, Emily Wang, G. Mark Voit
University Faculty Publications and Creative Works
We present UV broadband photometry and optical emission-line measurements for a sample of 32 brightest cluster galaxies (BCGs) in clusters of the Representative XMM-Newton Cluster Structure Survey (REXCESS) with z = 0.06-0.18. The REXCESS clusters, chosen to study scaling relations in clusters of galaxies, have X-ray measurements of high quality. The trends of star formation and BCG colors with BCG and host properties can be investigated with this sample. The UV photometry comes from the XMM-Newton Optical Monitor, supplemented by existing archival Galaxy Evolution Explorer photometry. We detected Hα and forbidden line emission in seven (22%) of these BCGs, in …
Brightest Cluster Galaxies And Core Gas Density In Rexcess Clusters, Deborah B. Haarsma, Luke Leisman, Megan Donahue, Seth Bruch
Brightest Cluster Galaxies And Core Gas Density In Rexcess Clusters, Deborah B. Haarsma, Luke Leisman, Megan Donahue, Seth Bruch
University Faculty Publications and Creative Works
We investigate the relationship between brightest cluster galaxies (BCGs) and their host clusters using a sample of nearby galaxy clusters from the Representative XMM-Newton Cluster Structure Survey. The sample was imaged with the Southern Observatory for Astrophysical Research in R band to investigate the mass of the old stellar population. Using a metric radius of 12 h -1kpc, we found that the BCG luminosity depends weakly on overall cluster mass as L BCG M 0.180.07cl, consistent with previous work. We found that 90% of the BCGs are located within 0.035 r 500 of the peak of the X-ray emission, including …
Star Formation And Uv Colors Of The Brightest Cluster Galaxies In The Representative Xmm-Newton Cluster Structure Survey, Megan Donahue, Seth Bruch, Emily Wang, G. Mark Voit
Star Formation And Uv Colors Of The Brightest Cluster Galaxies In The Representative Xmm-Newton Cluster Structure Survey, Megan Donahue, Seth Bruch, Emily Wang, G. Mark Voit
University Faculty Publications and Creative Works
We present UV broadband photometry and optical emission-line measurements for a sample of 32 brightest cluster galaxies (BCGs) in clusters of the Representative XMM-Newton Cluster Structure Survey (REXCESS) with z = 0.06-0.18. The REXCESS clusters, chosen to study scaling relations in clusters of galaxies, have X-ray measurements of high quality. The trends of star formation and BCG colors with BCG and host properties can be investigated with this sample. The UV photometry comes from the XMM-Newton Optical Monitor, supplemented by existing archival Galaxy Evolution Explorer photometry. We detected Hα and forbidden line emission in seven (22%) of these BCGs, in …
Brightest Cluster Galaxies And Core Gas Density In Rexcess Clusters, Deborah B. Haarsma, Luke Leisman, Megan Donahue, Seth Bruch
Brightest Cluster Galaxies And Core Gas Density In Rexcess Clusters, Deborah B. Haarsma, Luke Leisman, Megan Donahue, Seth Bruch
University Faculty Publications and Creative Works
We investigate the relationship between brightest cluster galaxies (BCGs) and their host clusters using a sample of nearby galaxy clusters from the Representative XMM-Newton Cluster Structure Survey. The sample was imaged with the Southern Observatory for Astrophysical Research in R band to investigate the mass of the old stellar population. Using a metric radius of 12 h -1kpc, we found that the BCG luminosity depends weakly on overall cluster mass as L BCG M 0.180.07cl, consistent with previous work. We found that 90% of the BCGs are located within 0.035 r 500 of the peak of the X-ray emission, including …
The Central Component Of Gravitational Lens Q0957+561, Deborah B. Haarsma, Joshua N. Winn, Irwin Shapiro, Joseph Lehár
The Central Component Of Gravitational Lens Q0957+561, Deborah B. Haarsma, Joshua N. Winn, Irwin Shapiro, Joseph Lehár
University Faculty Publications and Creative Works
In 1981, a faint radio source (G′) was detected near the center of the lensing galaxy of the famous "twin quasar" Q0957+561. It is still unknown whether this central radio source is a third quasar image or an active nucleus of the lensing galaxy, or a combination of both. In an attempt to resolve this ambiguity, we observed Q0957+561 at radio wavelengths of 13 cm, 18 cm, and 21 cm, using the Very Long Baseline Array in combination with the phased Very Large Array and the Green Bank Telescope. We measured the spectrum of G′ for the first time and …
The First-Optical-Vla Survey For Lensed Radio Lobes, Deborah B. Haarsma, Joshua N. Winn, Emilio E. Falco, Christopher S. Kochanek
The First-Optical-Vla Survey For Lensed Radio Lobes, Deborah B. Haarsma, Joshua N. Winn, Emilio E. Falco, Christopher S. Kochanek
University Faculty Publications and Creative Works
We present results from a survey for gravitationally lensed radio lobes. Lensed lobes are a potentially richer source of information about galaxy mass distributions than lensed point sources, which have been the exclusive focus of other recent surveys. Our approach is to identify radio lobes in the Faint Images of the Radio Sky at Twenty cm (FIRST) catalog and then search optical catalogs for coincident foreground galaxies, which are candidate lensing galaxies. We then obtain higher resolution images of these targets at both optical and radio wavelengths and obtain optical spectra for the most promising candidates. We present maps of …
An Extended Burst Tail From Sgr 1900+14 With A Thermal X-Ray Spectrum, Geoffrey T. Lenters, Peter M. Woods, Johnathan E. Goupell, Chryssa Kouveliotou
An Extended Burst Tail From Sgr 1900+14 With A Thermal X-Ray Spectrum, Geoffrey T. Lenters, Peter M. Woods, Johnathan E. Goupell, Chryssa Kouveliotou
University Faculty Publications and Creative Works
The soft gamma repeater SGR 1900+14 entered a new phase of activity in 2001 April initiated by the intermediate flare recorded on April 18. Ten days following this flare, we discovered an abrupt increase in the source flux between consecutive Rossi X-Ray Timing Explorer (RXTE) orbits. This X-ray flux excess decayed over the next several minutes and was subsequently linked to a high fluence burst from SGR 1900+14 recorded by other spacecraft (Ulysses and Wind/Konus) while the SGR was Earth-occulted for RXTE. We present here spectral and temporal analysis of both the burst of April 28 and the long X-ray …
Further Investigation Of The Time Delay, Magnification Ratios, And Variability In The Gravitational Lens 0218 + 357, A. S. Cohen, J. N. Hewitt, C. B. Moore, Deborah B. Haarsma
Further Investigation Of The Time Delay, Magnification Ratios, And Variability In The Gravitational Lens 0218 + 357, A. S. Cohen, J. N. Hewitt, C. B. Moore, Deborah B. Haarsma
University Faculty Publications and Creative Works
High-precision VLA flux density measurements for the lensed images of 0218 + 357 yield a time delay of 10.1 +1.5-1.6 days (95% confidence). This is consistent with independent measurements carried out at the same epoch by Biggs and colleagues in 1999, lending confidence to the robustness of the time delay measurement. However, since both measurements make use of the same features in the light curves, it is possible that the effects of unmodeled processes, such as scintillation or microlensing, are biasing both time delay measurements in the same way. Our time delay estimates result in confidence intervals that are somewhat …
Faint Radio Sources And Star Formation History, Deborah B. Haarsma, R. B. Partridge, R. A. Windhorst, E. A. Richards
Faint Radio Sources And Star Formation History, Deborah B. Haarsma, R. B. Partridge, R. A. Windhorst, E. A. Richards
University Faculty Publications and Creative Works
The centimeter-wave luminosity of local radio galaxies correlates well with their star formation rate. We extend this correlation to surveys of high-redshift radio sources to estimate the global star formation history. The star formation rate found from radio observations needs no correction for dust obscuration, unlike the values calculated from optical and ultraviolet data. Three deep radio surveys have provided catalogs of sources with nearly complete optical identifications and nearly 60% complete spectroscopic redshifts: the Hubble Deep Field and Flanking Fields at 12h + 62°, the SSA13 field at 13h + 42°, and the V15 field at 14h + 52°. …