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Origin: Metal Creation And Evolution From The Cosmic Dawn, J. W. den Herder, L. Piro, T. Ohashi, C. Kouveliotou, Dieter H. Hartmann, J. Kaastra, L. Amati, M. I. Andersen, M. Arnaud, J.-L. Attéia 2011 SRON Netherlands Institute for Space Research

Origin: Metal Creation And Evolution From The Cosmic Dawn, J. W. Den Herder, L. Piro, T. Ohashi, C. Kouveliotou, Dieter H. Hartmann, J. Kaastra, L. Amati, M. I. Andersen, M. Arnaud, J.-L. Attéia

Publications

ORIGIN is a proposal for the M3 mission call of ESA aimed at the study of metal creation from the epoch of cosmic dawn. Using high-spectral resolution in the soft X-ray band, ORIGIN will be able to identify the physical conditions of all abundant elements between C and Ni to red-shifts of z=10, and beyond. The mission will answer questions such as: When were the first metals created? How does the cosmic metal content evolve? Where do most of the metals reside in the Universe? What is the role of metals in structure formation and evolution? To reach out to …


The Swift/Fermi Grb 080928 From 1 Ev To 150 Kev, A. Rossi, S. Schulze, S. Klose, D. A. Kann, A. Rau, H. A. Krimm, G. Jóhannesson, A. Panaitescu, F. Yuan, P Ferrero, T Krühler, J Greiner, P Schady, S B. Pandey, L Amati, P.M.F. Afonso, C W. Akerlof, L A. Arnold, C Clemens, R Filgas, Dieter H. Hartmann 2011 Thüringer Landessternwarte Tautenburg

The Swift/Fermi Grb 080928 From 1 Ev To 150 Kev, A. Rossi, S. Schulze, S. Klose, D. A. Kann, A. Rau, H. A. Krimm, G. Jóhannesson, A. Panaitescu, F. Yuan, P Ferrero, T Krühler, J Greiner, P Schady, S B. Pandey, L Amati, P.M.F. Afonso, C W. Akerlof, L A. Arnold, C Clemens, R Filgas, Dieter H. Hartmann

Publications

We present the results of a comprehensive study of the gamma-ray burst 080928 and of its afterglow. GRB 080928 was a long burst detected by Swift/BAT and Fermi/GBM. It is one of the exceptional cases where optical emission had already been detected when the GRB itself was still radiating in the gamma-ray band. For nearly 100 s simultaneous optical, X-ray and gamma-ray data provide a coverage of the spectral energy distribution of the transient source from about 1 eV to 150 keV. In particular, we show that the SED during the main prompt emission phase agrees with synchrotron radiation. We …


The Nature Of “Dark” Gamma-Ray Bursts, J. Greiner, T. Krühler, S. Klose, P. Afonso, C. Clemens, R. Filgas, D. H. Hartmann, A. Küpcü Yoldas, M. Nardini, F. Olivares E., A. Rau, A. Rossi, P. Schady, Adria Updike 2011 Roger Williams University

The Nature Of “Dark” Gamma-Ray Bursts, J. Greiner, T. Krühler, S. Klose, P. Afonso, C. Clemens, R. Filgas, D. H. Hartmann, A. Küpcü Yoldas, M. Nardini, F. Olivares E., A. Rau, A. Rossi, P. Schady, Adria Updike

Arts & Sciences Faculty Publications

Context. Thirteen years after the discovery of the first afterglows, the nature of dark gamma-ray bursts (GRB) still eludes explanation: while each long-duration GRB typically has an X-ray afterglow, optical/NIR emission is only seen for 40–60% of them. Aims. Here we use the afterglow detection statistics of the systematic follow-up observations performed with GROND since mid-2007 in order to derive the fraction of “dark bursts” according to different methods, and to distinguish between various scenarios for “dark bursts”. Methods. Observations were performed with the 7-channel “Gamma-Ray Optical and Near-infrared Detector” (GROND) at the 2.2 m MPI/ESO telescope. We used the …


A Selection Of Hot Subluminous Stars In The Galex Survey – I. Correlation With The Guide Star Catalog, S. Vennes, A. Kawka, P. Nemeth 2011 Florida Institute of Technology

A Selection Of Hot Subluminous Stars In The Galex Survey – I. Correlation With The Guide Star Catalog, S. Vennes, A. Kawka, P. Nemeth

Aerospace, Physics, and Space Science Faculty Publications

We assembled a catalogue of bright, hot subdwarf and white dwarf stars extracted from a joint ultraviolet, optical and infrared source list. The selection is secured using colour criteria that correlate well with effective temperatures Teff≳ 12 000 K. We built a NUVV versus VJ diagram for ≳60 000 bright sources using the Galaxy Evolution Explorer (GALEX) NUV magnitude (NUV < 14), the associated Guide Star Catalog (GSC2.3.2) photographic quick-V magnitude and the Two-Micron All-Sky Survey J and H magnitudes. This distillation process delivered a catalogue of ≈700 sources with NUVV < 0.5 comprising ∼160 known hot subdwarf stars and another ∼60 known white dwarf stars. A reduced proper-motion diagram built using the proper-motion measurements extracted from the Naval Observatory Merged Astrometric Dataset allowed us to identify an additional ∼120 new hot subdwarf candidates and ∼10 hot white dwarf candidates. We present a spectroscopic study of a subset of 52 subdwarfs, 48 of them analysed here for the first time, and with nine objects brighter than V ∼ 12. …


The Two-Component Jet Of Grb 080413b, R. Filgas, T. Krühler, J. Greiner, A. Rau, E. Palazzi, S. Klose, P. Schady, A. Rossi, P. M.J. Afonso, L. A. Antonelli, C. Clemens, S. Covino, P. D’Avanzo, A. Küpcü Yoldas, M. Nardini, A. Nicuesa Guelbenzu, F. Olivares, Adria Updike, A. Yoldas 2011 Roger Williams University

The Two-Component Jet Of Grb 080413b, R. Filgas, T. Krühler, J. Greiner, A. Rau, E. Palazzi, S. Klose, P. Schady, A. Rossi, P. M.J. Afonso, L. A. Antonelli, C. Clemens, S. Covino, P. D’Avanzo, A. Küpcü Yoldas, M. Nardini, A. Nicuesa Guelbenzu, F. Olivares, Adria Updike, A. Yoldas

Arts & Sciences Faculty Publications

Aims. The quick and precise localization of GRBs by the Swift telescope allows the early evolution of the afterglow light curve to be captured by ground-based telescopes. With GROND measurements we can investigate the optical/near-infrared light curve of the afterglow of gamma-ray burst 080413B in the context of late rebrightening. Methods. Multi-wavelength follow-up observations were performed on the afterglow of GRB 080413B. X-ray emission was detected by the X-ray telescope onboard the Swift satellite and obtained from the public archive. Optical and near-infrared photometry was performed with the seven-channel imager GROND mounted at the MPG/ESO 2.2 m telescope and additionally …


The Effects Of Seductive Details In An Inflatable Planetarium, Sean Gillette 2011 Walden University

The Effects Of Seductive Details In An Inflatable Planetarium, Sean Gillette

Walden Dissertations and Doctoral Studies

Astronomy is becoming a forgotten science, which is evident by its relatively low enrollment figures compared to biology, chemistry, and physics. A portable inflatable planetarium brings relevance back to astronomy and offers support to students and educators by simulating realistic astronomical environments. This study sought to determine if learning is improved in an inflatable planetarium by adhering to the design principles of the cognitive theory of multimedia learning (CTML), specifically the coherence principle, in an authentic classroom. Two groups of 5th grade students of similar ability were purposefully assigned using a 1-teacher-to-many-students format with mean lesson lengths of 34 minutes. …


The Swift/Fermi Grb 080928 From 1 Ev To 150 Kev, A. Rossi, S. Schulze, S. Klose, D. A. Kann, A. Rau, H. A. Krimm, G. Jóhannesson, A. Panaitescu, F. Yuan, P. Ferrero, T. Krühler, J. Greiner, P. Schady, S. B. Pandey, L. Amati, P. M.J. Afonso, C. W. Akerlof, L. A. Arnold, C. Clemens, R. Filgas, D. H. Hartmann, A. Küpcü Yoldas, S. McBreen, T. A. McKay, A. Nicuesa Guelbenzu, F. E. Olivares, B. Paciesas, E. S. Rykoff, G. Szokoly, Adria Updike, A. Yoldas 2011 Roger Williams University

The Swift/Fermi Grb 080928 From 1 Ev To 150 Kev, A. Rossi, S. Schulze, S. Klose, D. A. Kann, A. Rau, H. A. Krimm, G. Jóhannesson, A. Panaitescu, F. Yuan, P. Ferrero, T. Krühler, J. Greiner, P. Schady, S. B. Pandey, L. Amati, P. M.J. Afonso, C. W. Akerlof, L. A. Arnold, C. Clemens, R. Filgas, D. H. Hartmann, A. Küpcü Yoldas, S. Mcbreen, T. A. Mckay, A. Nicuesa Guelbenzu, F. E. Olivares, B. Paciesas, E. S. Rykoff, G. Szokoly, Adria Updike, A. Yoldas

Arts & Sciences Faculty Publications

We present the results of a comprehensive study of the gamma-ray burst 080928 and of its afterglow. GRB 080928 was a long burst detected by Swift/BAT and Fermi/GBM. It is one of the exceptional cases where optical emission had already been detected when the GRB itself was still radiating in the gamma-ray band. For nearly 100 s simultaneous optical, X-ray and gamma-ray data provide a coverage of the spectral energy distribution of the transient source from about 1 eV to 150 keV. In particular, we show that the SED during the main prompt emission phase agrees with synchrotron radiation.We constructed …


Multi-Wavelength Observations Of The Flaring Gamma-Ray Blazar 3c 66a In 2008 October, P. T. Reynolds, Fermi-Lat, VERITAS, GASP-WEBT 2011 Cork Institute of Technology

Multi-Wavelength Observations Of The Flaring Gamma-Ray Blazar 3c 66a In 2008 October, P. T. Reynolds, Fermi-Lat, Veritas, Gasp-Webt

Physical Sciences Publications

The BL Lacertae object 3C 66A was detected in a flaring state by the Fermi Large Area Telescope (LAT) and VERITAS in 2008 October. In addition to these gamma-ray observations, F-GAMMA, GASP-WEBT, PAIRITEL, MDM, ATOM, Swift, and Chandra provided radio to X-ray coverage. The available light curves show variability and, in particular, correlated flares are observed in the optical and Fermi-LAT gamma-ray band. The resulting spectral energy distribution can be well fitted using standard leptonic models with and without an external radiation field for inverse Compton scattering. It is found, however, that only the model with an external …


Early Magnetic B-Type Stars: X-Ray Emission And Wind Properties, Lidia Oskinova, Helge Todt, Richard Ignace, John Brown, Joseph Cassinelli, Wolf-Rainer Hamann 2011 East Tennessee State University

Early Magnetic B-Type Stars: X-Ray Emission And Wind Properties, Lidia Oskinova, Helge Todt, Richard Ignace, John Brown, Joseph Cassinelli, Wolf-Rainer Hamann

ETSU Faculty Works

We present a comprehensive study of X-ray emission and wind properties of magnetic early B-type stars. We compile the complete sample of early B-type stars with detected magnetic fields to date and existing X-ray measurements, in order to study whether the X-ray emission can be used as a general proxy for stellar magnetism. For the first time we analyze the UV spectra of B stars with magnetic fields by means of non-LTE iron-blanketed stellar atmosphere model that account for the X-rays at the intensity and temperatures observed. The mass-loss rates inferred from the analysis of UV lines are significantly lower …


The Energy Source Of The Filaments Around The Giant Galaxy Ngc 1275, A. C. Fabian, J. S. Sanders, R. J. R. Williams, A. Lazarian, Gary J. Ferland, R. M. Johnstone 2011 Institute of Astronomy, UK

The Energy Source Of The Filaments Around The Giant Galaxy Ngc 1275, A. C. Fabian, J. S. Sanders, R. J. R. Williams, A. Lazarian, Gary J. Ferland, R. M. Johnstone

Physics and Astronomy Faculty Publications

The brightest galaxy in the nearby Perseus cluster, NGC 1275, is surrounded by a network of filaments. These were first observed through their Hα emission but are now known to have a large molecular component with a total mass approaching 1011 M of gas. The filaments are embedded in hot intracluster gas and stretch over 80 kpc. They have an unusually low excitation spectrum which is well modelled by collisional heating and ionization by secondary electrons. Here we note that the surface radiative flux from the outer filaments is close to the energy flux impacting on them from …


Herschel Observations Of The Centaurus Oluster - The Dynamics Of Cold Gas In A Cool Core, R. Mittal, C. P. O'Dea, Gary J. Ferland, J. B. R. Oonk, A. C. Edge, R. E. A. Canning, H. Russell, S. A. Baum, H. Böhringer, F. Combes, M. Donahue, A. C. Fabian, N. A. Hatch, A. Hoffer, R. Johnstone, B. R. McNamara, P. Salomé, G. Tremblay 2011 Rochester Institute of Technology

Herschel Observations Of The Centaurus Oluster - The Dynamics Of Cold Gas In A Cool Core, R. Mittal, C. P. O'Dea, Gary J. Ferland, J. B. R. Oonk, A. C. Edge, R. E. A. Canning, H. Russell, S. A. Baum, H. Böhringer, F. Combes, M. Donahue, A. C. Fabian, N. A. Hatch, A. Hoffer, R. Johnstone, B. R. Mcnamara, P. Salomé, G. Tremblay

Physics and Astronomy Faculty Publications

Brightest cluster galaxies (BCGs) in the cores of galaxy clusters have distinctly different properties from other low-redshift massive ellipticals. The majority of the BCGs in cool-core clusters show signs of active star formation. We present observations of NGC 4696, the BCG of the Centaurus galaxy cluster, at far-infrared (FIR) wavelengths with theHerschel space telescope. Using the PACS spectrometer, we detect the two strongest coolants of the interstellar medium, [C II] at 157.74 μm and [O I] at 63.18 μm, and in addition [N II] at 121.90 μm. The [C II] emission is extended over a region of 7 kpc …


A Deep Spectroscopic Study Of The Filamentary Nebulosity In Ngc 4696, The Brightest Cluster Galaxy In The Centaurus Cluster, R. E. A. Canning, A. C. Fabian, R. M. Johnstone, J. S. Sanders, C. S. Crawford, Gary J. Ferland, N. A. Hatch 2011 University of Cambridge, UK

A Deep Spectroscopic Study Of The Filamentary Nebulosity In Ngc 4696, The Brightest Cluster Galaxy In The Centaurus Cluster, R. E. A. Canning, A. C. Fabian, R. M. Johnstone, J. S. Sanders, C. S. Crawford, Gary J. Ferland, N. A. Hatch

Physics and Astronomy Faculty Publications

We present results of deep integral-field spectroscopy observations using high-resolution optical (4150–7200 Å) VLT VIsible MultiObject Spectrograph spectra of NGC 4696, the dominant galaxy in the Centaurus cluster (Abell 3526). After the Virgo cluster, this is the second nearest (z= 0.0104) example of a cool-core cluster. NGC 4696 is surrounded by a vast, luminous Hα emission-line nebula (L= 2.2 × 1040 erg s−1). We explore the origin and excitation of the emission-line filaments and find their origin consistent with being drawn out, under rising radio bubbles, into the intracluster medium as in …


Monster In The Dark: The Ultraluminous Grb 080607 And Its Dusty Environment, D.A. Perley, A.N. Morgan, Adria Updike, F. Yuan, C.W. Akerlof, A.A. Miller, J.S. Bloom, S.B. Cenko, W. Li, A.V. Filippenko, J.X. Prochaska, D.A. Kann, N.R. Tanvir, A.J. Levan, N.R. Butler, P. Christian, D.H. Hartmann, P. Milne, E.S. Rykoff, W. Rujopakarn, J.C. Wheeler, G.G. Williams 2011 Roger Williams University

Monster In The Dark: The Ultraluminous Grb 080607 And Its Dusty Environment, D.A. Perley, A.N. Morgan, Adria Updike, F. Yuan, C.W. Akerlof, A.A. Miller, J.S. Bloom, S.B. Cenko, W. Li, A.V. Filippenko, J.X. Prochaska, D.A. Kann, N.R. Tanvir, A.J. Levan, N.R. Butler, P. Christian, D.H. Hartmann, P. Milne, E.S. Rykoff, W. Rujopakarn, J.C. Wheeler, G.G. Williams

Arts & Sciences Faculty Publications

We present early-time optical through infrared photometry of the bright Swift gamma-ray burst (GRB) 080607, starting only 6 s following the initial trigger in the rest frame. Complemented by our previously published spectroscopy, this high-quality photometric data set allows us to solve for the extinction properties of the redshift 3.036 sightline, giving perhaps the most detailed information to date on the ultraviolet continuum absorption properties of any sightline outside our Local Group. The extinction properties are not adequately modeled by any ordinary extinction template (including the average Milky Way, Large Magellanic Cloud, and Small Magellanic Cloud curves), partially because the …


Unidirectional Invisibility Induced By Pt-Symmetric Periodic Structures, Zin Lin, Hamidreza Ramezani 2011 The University of Texas Rio Grande Valley

Unidirectional Invisibility Induced By Pt-Symmetric Periodic Structures, Zin Lin, Hamidreza Ramezani

Physics & Astronomy Faculty Publications

Parity-time (PT) symmetric periodic structures, near the spontaneous PT-symmetry breaking point, can act as unidirectional invisible media. In this regime, the reflection from one end is diminished while it is enhanced from the other. Furthermore, the transmission coefficient and phase are indistinguishable from those expected in the absence of a grating. The phenomenon is robust even in the presence of Kerr nonlinearities, and it can also effectively suppress optical bistabilities.


Balloon Borne Mars Research Platforms, Sean Michael Hancock 2011 Old Dominion University

Balloon Borne Mars Research Platforms, Sean Michael Hancock

Mechanical & Aerospace Engineering Theses & Dissertations

Aerial platforms can fill a measurement gap between orbiters and rovers, providing planetary scale high resolution in situ measurements, access to scientifically interesting terrain that is either inaccessible or hazardous to rovers, and serve as a planet-wide delivery platforms to deploy surface probes and rovers to areas inaccessible given existing entry, descent, and landing systems. A permanent robotic outpost on the Martian surface can utilize locally-derived hydrogen as a lifting gas for balloon systems deployed from Mars. That approach can simplify the inflation and launch of aerial vehicles while allowing for a long duration deployment campaign that is not constrained …


Grb 090426: Discovery Of A Jet Break In A Short Burst Afterglow, A. Nicuesa Guelbenzu, S. Klose, A. Rossi, D.A. Kann, T. Krühler, J. Greiner, A. Rau, F. Olivares E., P.M.J. Afonso, R. Filgas, A. Küpcü Yoldas, S. McBreen, M. Nardini, P. Schady, S. Schmidl, Adria Updike, A. Yoldas 2011 Roger Williams University

Grb 090426: Discovery Of A Jet Break In A Short Burst Afterglow, A. Nicuesa Guelbenzu, S. Klose, A. Rossi, D.A. Kann, T. Krühler, J. Greiner, A. Rau, F. Olivares E., P.M.J. Afonso, R. Filgas, A. Küpcü Yoldas, S. Mcbreen, M. Nardini, P. Schady, S. Schmidl, Adria Updike, A. Yoldas

Arts & Sciences Faculty Publications

Context. The link between the duration of GRBs and the nature of their progenitors remains disputed. Short bursts (with durations of less than ∼2 s) are less frequently observed, technically more difficult to localize, and exhibit significantly fainter afterglows. Aims. It is of critical importance to establish whether the burst duration can reliably distinguish the different GRB population models of collapsars and compact stellar mergers. The Swift GRB 090426 provides an unique opportunity to address this question. Its duration (T90 = 1.28 s) places GRB 090426 firmly in the short burst population, while the high redshift (z = 2.609), host …


The Study Of Variability In Four Oxygen-Rich Proto-Planetary Nebulae, Kristie Shaw 2011 Valparaiso University

The Study Of Variability In Four Oxygen-Rich Proto-Planetary Nebulae, Kristie Shaw

Symposium on Research and Creative Expression (SORCE)

This summer, I have been working on a project to study the variability of four proto-planetary nebulae. Proto-planetary nebulae (PPNe) are evolved stellar objects that are in the process of losing their outer layers and in transition from a red giant star to a planetary nebula. Oxygen-rich PPNe, specifically, have a higher oxygen content in their nebula than they do carbon, and this occurs mainly in lower mass stars. This project includes combining our data from the VU Observatory with other published data, analyzing light curves of brightness versus time and looking for patterns, and performing period analysis using a …


Mount Graham, Janet Butler Munch 2011 CUNY Lehman College

Mount Graham, Janet Butler Munch

Publications and Research

Mount Graham, in southern Arizona, is considered a sacred location by the Apaches. The remoteness and high elevation of the mountain makes it an ideal location for astronomical research. After protracted litigation suits, the University of Arizona prevailed and was allowed to establish the Mount Graham International Observatory on the site.


The Vlt Lbg Redshift Survey- Ii. Interactions Between Galaxies And The Igm At Z ~ 3, N. H.M. Crighton, R. Bielby, T. Shanks, L. Infante, C. G. Bornancini, N. Bouché, D. G. Lambas, James D. Lowenthal, D. Minniti, S. L. Morris, N. Padilla, C. Péroux, P. Petitjean, T. Theuns, P. Tummuangpak, P. M. Weilbacher, L. Wisotzki, G. Worseck 2011 Durham University

The Vlt Lbg Redshift Survey- Ii. Interactions Between Galaxies And The Igm At Z ~ 3, N. H.M. Crighton, R. Bielby, T. Shanks, L. Infante, C. G. Bornancini, N. Bouché, D. G. Lambas, James D. Lowenthal, D. Minniti, S. L. Morris, N. Padilla, C. Péroux, P. Petitjean, T. Theuns, P. Tummuangpak, P. M. Weilbacher, L. Wisotzki, G. Worseck

Astronomy: Faculty Publications

We have measured redshifts for 243 z≈ 3 quasars in nine Very Large Telescope (VLT) Visible Imaging and Multi-Object Spectrograph (VIMOS) Lyman-break galaxy (LBG) redshift survey areas, each of which is centred on a known bright quasar. Using the spectra of these quasars, we measure the cross-correlation between neutral hydrogen gas causing the Lyα forest and 1020 LBGs at z≈ 3. We find an increase in neutral hydrogen absorption within ≈5h Mpc of a galaxy in agreement with the results of Adelberger et al. The Lyα-LBG cross-correlation can be described by a power law on scales larger than 3h Mpc. …


Suppression Of Away-Side Jet Fragments With Respect To The Reaction Plane In Au + Au Collisions At √Snn=200 Gev, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Szabolcs Rembeczki, Marcus Hohlmann 2011 University of Colorado, Boulder

Suppression Of Away-Side Jet Fragments With Respect To The Reaction Plane In Au + Au Collisions At √Snn=200 Gev, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Szabolcs Rembeczki, Marcus Hohlmann

Aerospace, Physics, and Space Science Faculty Publications

Pair correlations between large transverse momentum neutral pion triggers (pT=4 - 7 GeV/c) and charged hadron partners (pT=3 - 7 GeV/c) in central (0%-20%) and midcentral (20%-60%) Au+Au collisions at √sNN=200 GeV are presented as a function of trigger orientation with respect to the reaction plane. The particles are at larger momentum than where jet shape modifications have been observed, and the correlations are sensitive to the energy loss of partons traveling through hot dense matter. An out-of-plane trigger particle produces only 26±20% of the away-side pairs that are observed opposite of an in-plane trigger particle for midcentral (20%-60%) collisions. …


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