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- Galaxies (5)
- Seyfert (4)
- Quasars (2)
- Accretion (1)
- Accretion disks (1)
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- Arp 151 (1)
- Artificial intelligence (1)
- BL Lacertae objects: general – galaxies: active – galaxies: jets – radio continuum: galaxies Online-only material: color figures (1)
- Black hole physics (1)
- Black hole physics; galaxies (1)
- CUORICINO (1)
- Computer tutorial (1)
- Cosmic rays (1)
- Cosmology (1)
- Dark matter – galaxies: dwarf – gamma rays: galaxies (1)
- Degradation (1)
- Diffusion (1)
- Dome A (1)
- Double beta decay (1)
- Electron acceptor (1)
- Emission lines (1)
- Fullerenes (1)
- Galaxies interactions (1)
- Kinematics (1)
- Kinematics and dynamics (1)
- Muons (1)
- Neutrinos (1)
- Physics (1)
- Polymer photovoltaic (1)
- Prolog (1)
Articles 1 - 30 of 30
Full-Text Articles in Physics
Projection Of Diffraction Patterns For Use In Cold-Neutral-Atom Trapping, Katharina Gillen-Christandl, Glen D. Gillen
Projection Of Diffraction Patterns For Use In Cold-Neutral-Atom Trapping, Katharina Gillen-Christandl, Glen D. Gillen
Physics
Scalar diffraction theory is combined with beam-propagation techniques to investigate the projection of near-field diffraction patterns to spatial locations away from the aperture for use in optically trapping cold neutral alkali-metal atoms. Calculations show that intensity distributions with localized bright and dark spots usually found within a millimeter of the diffracting aperture can be projected to a region free from optical components such as a cloud of cold atoms within a vacuum chamber. Calculations also predict that the critical properties of the optical dipole atom traps are not only maintained for the projected intensity patterns but also can be manipulated …
The Lick Agn Monitoring Project: Alternate Routes To A Broad-Line Region Radius, Jenny E. Greene, Carol E. Hood, Aaron J. Barth, Vardha N. Bennert, Misty C. Benz, Alexei V. Filippenko, Elinor Gates, Matthew A. Malkan, Tommaso Treu, Jonelle L. Walsh, Jong-Hak Woo
The Lick Agn Monitoring Project: Alternate Routes To A Broad-Line Region Radius, Jenny E. Greene, Carol E. Hood, Aaron J. Barth, Vardha N. Bennert, Misty C. Benz, Alexei V. Filippenko, Elinor Gates, Matthew A. Malkan, Tommaso Treu, Jonelle L. Walsh, Jong-Hak Woo
Physics
It is now possible to estimate black hole (BH) masses across cosmic time, using broad emission lines in active galaxies. This technique informs our views of how galaxies and their central BHs coevolve. Unfortunately, there are many outstanding uncertainties associated with these "virial" mass estimates. One of these comes from using the accretion luminosity to infer a size for the broad-line region (BLR). Incorporating the new sample of low-luminosity active galaxies from our recent monitoring campaign at Lick Observatory, we recalibrate the radius-luminosity relation with tracers of the accretion luminosity other than the optical continuum. We find that the radius …
Rf System Models For The Cern Large Hadron Collider With Application To Longitudinal Dynamics, T. Mastorides, C. Rivetta, J.D. Fox, D. Van Winkle, P. Baudrenghien
Rf System Models For The Cern Large Hadron Collider With Application To Longitudinal Dynamics, T. Mastorides, C. Rivetta, J.D. Fox, D. Van Winkle, P. Baudrenghien
Physics
The LHC RF station-beam interaction strongly influences the longitudinal beam dynamics, both single bunch and collective effects. Non-linearities and noise generated within the Radio Frequency (RF) accelerating system interact with the beam and contribute to beam motion and longitudinal emittance blowup. Thus, the noise power spectrum of the RF accelerating voltage strongly affects the longitudinal beam distribution. Furthermore, the coupled-bunch instabilities are also directly affected by the RF components and the configuration of the Low Level RF (LLRF) feedback loops. In this work we present a formalism relating the longitudinal beam dynamics with the RF system configurations, an estimation of …
Veritas Search For Vhe Gamma-Ray Emission From Dwarf Spheroidal Galaxies, V. A. Acciari, T. Arlen, T. Aune, M. Beilicke, W. Benbow, D. Boltuch, S. M. Bradbury, J. H. Buckley, V. Bugaev, K. Byrum, A. Cannon, A. Cesarini, Jodi L. Christiansen, L. Ciupik, W. Cui, R. Dickherber, C. Duke, J. P. Finley, G. Finnegan, A. Furniss, N. Galante, S. Godambe, J. Grube, R. Guenette, G. Gyuk, D. Hanna, J. Holder, C. M. Hui, T. B. Humensky, A. Imran, P. Kaaret, N. Karlsson, M. Kertzman, D. Kieda, A. Konopelko, H. Krawczynski, F. Krennrich, G. Maier, S. Mcarthur, A. Mccann, M. Mccutcheon, P. Moriarty, R. A. Ong, A. N. Otte, D. Pandel, J. S. Perkins, M. Pohl, J. Quinn, K. Ragan, L. C. Reyes, P. T. Reynolds, E. Roache, H. J. Rose, M. Schroedter, G. H. Sembroski, G. D. Senturk, A. W. Smith, D. Steele, S. P. Swordy, G. Tesic, M. Theiling, S. Thibadeau, A. Varlotta, V. V. Vassiliev, S. Vincent, R. G. Wagner, S. P. Wakely, J. E. Ward, T. C. Weekes, A. Weinstein, T. Weisgarber, D. A. Williams, S. Wissel, B. Zitzer
Veritas Search For Vhe Gamma-Ray Emission From Dwarf Spheroidal Galaxies, V. A. Acciari, T. Arlen, T. Aune, M. Beilicke, W. Benbow, D. Boltuch, S. M. Bradbury, J. H. Buckley, V. Bugaev, K. Byrum, A. Cannon, A. Cesarini, Jodi L. Christiansen, L. Ciupik, W. Cui, R. Dickherber, C. Duke, J. P. Finley, G. Finnegan, A. Furniss, N. Galante, S. Godambe, J. Grube, R. Guenette, G. Gyuk, D. Hanna, J. Holder, C. M. Hui, T. B. Humensky, A. Imran, P. Kaaret, N. Karlsson, M. Kertzman, D. Kieda, A. Konopelko, H. Krawczynski, F. Krennrich, G. Maier, S. Mcarthur, A. Mccann, M. Mccutcheon, P. Moriarty, R. A. Ong, A. N. Otte, D. Pandel, J. S. Perkins, M. Pohl, J. Quinn, K. Ragan, L. C. Reyes, P. T. Reynolds, E. Roache, H. J. Rose, M. Schroedter, G. H. Sembroski, G. D. Senturk, A. W. Smith, D. Steele, S. P. Swordy, G. Tesic, M. Theiling, S. Thibadeau, A. Varlotta, V. V. Vassiliev, S. Vincent, R. G. Wagner, S. P. Wakely, J. E. Ward, T. C. Weekes, A. Weinstein, T. Weisgarber, D. A. Williams, S. Wissel, B. Zitzer
Physics
Indirect dark matter searches with ground-based gamma-ray observatories provide an alternative for identifying the particle nature of dark matter that is complementary to that of direct search or accelerator production experiments. We present the results of observations of the dwarf spheroidal galaxies Draco, Ursa Minor, Bootes 1, and Willman 1 conducted by the Very Energetic Radiation Imaging Telescope Array System (VERITAS). These galaxies are nearby dark matter dominated objects located at a typical distance of several tens of kiloparsecs for which there are good measurements of the dark matter density profile from stellar velocity measurements. Since the conventional astrophysical background …
The Lick Agn Monitoring Project: Velocity-Delay Maps From The Maximum-Entropy Method For Arp 151, Misty C. Bentz, Keith Horne, Aaron J. Barth, Vardha Nicola Bennert, Gabriela Canalizo, Alexei V. Filippenko, Elinor L. Gates, Matthew A. Malkan, Takeo Minezaki, Tommaso Treu, Jong-Hak Woo, Jonelle L. Walsh
The Lick Agn Monitoring Project: Velocity-Delay Maps From The Maximum-Entropy Method For Arp 151, Misty C. Bentz, Keith Horne, Aaron J. Barth, Vardha Nicola Bennert, Gabriela Canalizo, Alexei V. Filippenko, Elinor L. Gates, Matthew A. Malkan, Takeo Minezaki, Tommaso Treu, Jong-Hak Woo, Jonelle L. Walsh
Physics
We present velocity-delay maps for optical H I, He I, and He II recombination lines in Arp 151, recovered by fitting a reverberation model to spectrophotometric monitoring data using the maximum-entropy method. H I response is detected over the range 0-15 days, with the response confined within the virial envelope. The Balmer-line maps have similar morphologies but exhibit radial stratification, with progressively longer delays for Hγ to Hβ to Hα. The He I and He II response is confined within 1-2 days. There is a deficit of prompt response in the Balmer-line cores but strong prompt response in the red …
U–Pb Zircon Geochronology And Tectonostratigraphy Of Southern Liverpool Land, East Greenland: Implications For Deformation In The Overriding Plates Of Continental Collisions, Scott M. Johnston, Ebbe H. Hartz, Hannes K. Brueckner, George E. Gehrels
U–Pb Zircon Geochronology And Tectonostratigraphy Of Southern Liverpool Land, East Greenland: Implications For Deformation In The Overriding Plates Of Continental Collisions, Scott M. Johnston, Ebbe H. Hartz, Hannes K. Brueckner, George E. Gehrels
Physics
The East Greenland Caledonides formed in the overriding plate as Baltica was subducted westward beneath Laurentia from 460 to 360 Ma, and offer a unique opportunity to investigate lower crustal deformation in the overriding plates of continental collisions. Field work and new zircon geochronology from gneisses in southern Liverpool Land, exposed in the hinterland ~100 km east of the nearest Caledonian gneisses, define three tectonostratigraphic units that are, from the bottom up, the eclogite+peridotite-bearing Tværdal complex and the granulite-facies Jættedal complex in the footwall of the top-N Gubbedalen shear zone, and the Hurry Inlet granite and associated paragneiss screens in …
Muon-Induced Backgrounds In The Cuoricino Experiment, E. Andreotti, C. Arnaboldi, F.T. Avignone Iii, M. Balata, I. Bandac, M. Barucci, J.W. Beeman, F. Bellini, T. Bloxham, C. Brofferio, A. Bryant, C. Bucci, L. Canonica, S. Capelli, L. Carbone, M. Carrettoni, M. Clemenza, O. Cremonesi, R.J. Creswick, S. Di Domizio, M.J. Dolinski, L. Ejzak, R. Faccini, H.A. Farach, E. Ferri, F. Ferroni, E. Fiorini, L. Foggetta, A. Giachero, L. Gironi, A. Giuliani, P. Gorla, E. Guardincerri, T.D. Gutierrez, E.E. Haller, R. Kadel, K. Kazkaz, S. Kraft, L. Kogler, Yu. G. Kolomensky, C. Maiano, R.H. Maruyama, C. Martinez, M. Martinez, L. Mizouni, S. Morganti, S. Nisi, C. Nones, E.B. Norman, A. Nucciotti, F. Orio, M. Pallavicini, V. Palmieri, L. Pattavina, M. Pavan, M. Pedretti, G. Pessina, S. Pirro, E. Previtali, L. Risegari, C. Rosenfeld, C. Rusconi, C. Salvioni, S. Sangiorgio, D. Schaeffer, N.D. Scielzo, M. Sisti, A.R. Smith, C. Tomei, G. Ventura, M. Vignati
Muon-Induced Backgrounds In The Cuoricino Experiment, E. Andreotti, C. Arnaboldi, F.T. Avignone Iii, M. Balata, I. Bandac, M. Barucci, J.W. Beeman, F. Bellini, T. Bloxham, C. Brofferio, A. Bryant, C. Bucci, L. Canonica, S. Capelli, L. Carbone, M. Carrettoni, M. Clemenza, O. Cremonesi, R.J. Creswick, S. Di Domizio, M.J. Dolinski, L. Ejzak, R. Faccini, H.A. Farach, E. Ferri, F. Ferroni, E. Fiorini, L. Foggetta, A. Giachero, L. Gironi, A. Giuliani, P. Gorla, E. Guardincerri, T.D. Gutierrez, E.E. Haller, R. Kadel, K. Kazkaz, S. Kraft, L. Kogler, Yu. G. Kolomensky, C. Maiano, R.H. Maruyama, C. Martinez, M. Martinez, L. Mizouni, S. Morganti, S. Nisi, C. Nones, E.B. Norman, A. Nucciotti, F. Orio, M. Pallavicini, V. Palmieri, L. Pattavina, M. Pavan, M. Pedretti, G. Pessina, S. Pirro, E. Previtali, L. Risegari, C. Rosenfeld, C. Rusconi, C. Salvioni, S. Sangiorgio, D. Schaeffer, N.D. Scielzo, M. Sisti, A.R. Smith, C. Tomei, G. Ventura, M. Vignati
Physics
To better understand the contribution of cosmic ray muons to the CUORICINO background, 10 plastic scintillator detectors were installed at the CUORICINO site and operated during the final 3 months of the experiment. From these measurements, an upper limit of 0.0021 counts/(keV kg yr) (95% CL) was obtained on the cosmic ray-induced background in the neutrinoless double beta decay region of interest. The measurements were also compared to GEANT4 simulations.
The Lick Agn Monitoring Project: Reverberation Mapping Of Optical Hydrogen And Helium Recombination Lines, Misty C. Bentz, Jonelle L. Walsh, Aaron J. Barth, Yuzuru Yoshii, Jong-Hak Woo, Xiaofeng Wang, Tommaso Treu, Carol E. Thornton, Rachel A. Street, Thea N. Steele, Jeffrey M. Silverman, Frank J.D. Serduke, Yu Sakata, Takeo Minezaki, Matthew A. Malkan, Weidong Li, Nicholas Lee, Kyle D. Hiner, Marton G. Hidas, Jenny E. Greene, Elinor L. Gates, Mohan Ganeshalingam, Alexei V. Filippenko, Gabriela Canalizo, Vardha N. Bennert, Nairn Baliber
The Lick Agn Monitoring Project: Reverberation Mapping Of Optical Hydrogen And Helium Recombination Lines, Misty C. Bentz, Jonelle L. Walsh, Aaron J. Barth, Yuzuru Yoshii, Jong-Hak Woo, Xiaofeng Wang, Tommaso Treu, Carol E. Thornton, Rachel A. Street, Thea N. Steele, Jeffrey M. Silverman, Frank J.D. Serduke, Yu Sakata, Takeo Minezaki, Matthew A. Malkan, Weidong Li, Nicholas Lee, Kyle D. Hiner, Marton G. Hidas, Jenny E. Greene, Elinor L. Gates, Mohan Ganeshalingam, Alexei V. Filippenko, Gabriela Canalizo, Vardha N. Bennert, Nairn Baliber
Physics
We have recently completed a 64-night spectroscopic monitoring campaign at the Lick Observatory 3 m Shane telescope with the aim of measuring the masses of the black holes in 12 nearby (z < 0.05) Seyfert 1 galaxies with expected masses in the range ~106-107 M ☉ and also the well-studied nearby active galactic nucleus (AGN) NGC 5548. Nine of the objects in the sample (including NGC 5548) showed optical variability of sufficient strength during the monitoring campaign to allow for a time lag to be measured between the continuum fluctuations and the response to these fluctuations in the broad Hβ emission, which we have previously reported. We present …
The Lick Agn Monitoring Project: The M Bh-Σ* Relation For Reverberation-Mapped Active Galaxies, Jong-Hak Woo, Tommaso Treu, Aaron J. Barth, Shelley A. Wright, Jonelle L. Walsh, Misty C. Bentz, Paul Martini, Vardha N. Bennert, Gabriela Canalizo, Alexei V. Filippenko, Elinor Gates, Jenny Greene, Weidong Li, Matthew A. Malkan, Daniel Stern, Takeo Minezaki
The Lick Agn Monitoring Project: The M Bh-Σ* Relation For Reverberation-Mapped Active Galaxies, Jong-Hak Woo, Tommaso Treu, Aaron J. Barth, Shelley A. Wright, Jonelle L. Walsh, Misty C. Bentz, Paul Martini, Vardha N. Bennert, Gabriela Canalizo, Alexei V. Filippenko, Elinor Gates, Jenny Greene, Weidong Li, Matthew A. Malkan, Daniel Stern, Takeo Minezaki
Physics
To investigate the black hole mass versus stellar velocity dispersion (M BH-σ*) relation of active galaxies, we measured the velocity dispersions of a sample of local Seyfert 1 galaxies, for which we have recently determined black hole masses using reverberation mapping. For most objects, stellar velocity dispersions were measured from high signal-to-noise ratio optical spectra centered on the Ca II triplet region (~8500 Å), obtained at the Keck, Palomar, and Lick Observatories. For two objects, in which the Ca II triplet region was contaminated by nuclear emission, the measurement was based on high-quality H-band spectra …
Moderately Thermophilic Magnetotactic Bacteria From Hot Springs In Nevada, Christopher T. Lefevre, Fernanda Abreu, Marian L. Schimdt, Ulysses Lins, Richard B. Frankel, Brian P. Hedlund, Dennis A. Bazylinski
Moderately Thermophilic Magnetotactic Bacteria From Hot Springs In Nevada, Christopher T. Lefevre, Fernanda Abreu, Marian L. Schimdt, Ulysses Lins, Richard B. Frankel, Brian P. Hedlund, Dennis A. Bazylinski
Physics
Populations of a moderately thermophilic magnetotactic bacterium were discovered in Great Boiling Springs, Nevada, ranging from 32 to 63°C. Cells were small, Gram-negative, vibrioid to helicoid in morphology, and biomineralized a chain of bullet-shaped magnetite magnetosomes. Phylogenetically, based on 16S rRNA gene sequencing, the organism belongs to the phylum Nitrospirae.
Lhc Beam Diffusion Dependence On Rf Noise: Models And Measurements, T. Mastoridis, C. Rivetta, J.D. Fox, D. Van Winkle, P. Baudrenghien, A. Butterworth, J. Molendijk
Lhc Beam Diffusion Dependence On Rf Noise: Models And Measurements, T. Mastoridis, C. Rivetta, J.D. Fox, D. Van Winkle, P. Baudrenghien, A. Butterworth, J. Molendijk
Physics
Radio Frequency (RF) accelerating system noise and non-idealities can have detrimental impact on the LHC performance through longitudinal motion and longitudinal emittance growth. A theoretical formalism has been developed to relate the beam and RF loop dynamics with the bunch length growth [1]. Measurements were conducted at LHC to validate the formalism, determine the performance limiting RF components, and provide the foundation for beam diffusion estimates for higher energies and intensities. A brief summary of these results is presented in this work.
Sps Ecloud Instabilities - Analysis Of Machine Studies And Implications For Ecloud Feedback, J.D. Fox, A. Bullitt, T. Mastoridis, G. Ndabashimiye, C. Rivetta, O. Turgut, D. Van Winkle, J. Byrd, M. Furman, J-L. Vay, W. Hofle, G. Rumolo, R. De Maria
Sps Ecloud Instabilities - Analysis Of Machine Studies And Implications For Ecloud Feedback, J.D. Fox, A. Bullitt, T. Mastoridis, G. Ndabashimiye, C. Rivetta, O. Turgut, D. Van Winkle, J. Byrd, M. Furman, J-L. Vay, W. Hofle, G. Rumolo, R. De Maria
Physics
The SPS at high intensities exhibits transverse singlebunch instabilities with signatures consistent with an Ecloud driven instability.[1] We present recent MD data from the SPS, details of the instrument technique and spectral analysis methods which help reveal complex vertical motion that develops within a subset of the injected bunch trains. The beam motion is detected via wideband exponential taper striplines and delta-sigma hybrids. The raw sum and difference data is sampled at 50 GHz with 1.8 GHz bandwidth. Sliding window FFT techniques and RMS motion techniques show the development of large vertical tune shifts on portions of the bunch of …
Commissioning Of The Lch Low Level Rf System Remote Configuration Tools, D. Van Winkle, C. Rivetta, T. Mastoridis, J. Fox, P. Baudrenghien, A. Butterworth, J. Molendijk
Commissioning Of The Lch Low Level Rf System Remote Configuration Tools, D. Van Winkle, C. Rivetta, T. Mastoridis, J. Fox, P. Baudrenghien, A. Butterworth, J. Molendijk
Physics
The LHC Low Level RF system (LLRF) is a complex multi-loop system used to regulate the superconductive cavity gap voltage as well as to reduce the impedance presented by RF stations to the beam. The RF system can have a profound impact on the stability of the beam; a mis-configured RF system has the potential of causing longitudinal instabilities, beam diffusion and beam loss. To configure the RF station for operation, a set of parameters in the LLRF multi-loop system have to be defined. Initial system commissioning as well as ongoing operation requires a consistent method of computer based remote …
Lessons Learned From Positon-Electron Project Low Level Rf And Longitudinal Feedback, J. Fox, Themis Mastorides, C. Rivetta, D. Van Winkle, D. Teytelman
Lessons Learned From Positon-Electron Project Low Level Rf And Longitudinal Feedback, J. Fox, Themis Mastorides, C. Rivetta, D. Van Winkle, D. Teytelman
Physics
The PEP-II B-Factory collider ended the final phase of operation at nearly twice the design current and 4X the design luminosity. To highlight the evolution from the original conceptual design through to the 1.2E34 final machine we choose one example each from the broadband feedback and from the LLRF system. They illustrate the original design estimation missed some very significant details, and how in the course of PEP-II operation unexpected difficulties led to significant insights and new approaches which allowed higher machine performance. We present valuable ”lessons learned” which are of interest to designers of next generation feedback and impedance …
Prospective Type Ia Supernova Surveys From Dome A, A. Kim, A. Bonissent, Jodi L. Christiansen, A. Ealet, L. Faccioli, L. Gladney, G. Kushner, E. Linder, C. Stoughton, L. Wang
Prospective Type Ia Supernova Surveys From Dome A, A. Kim, A. Bonissent, Jodi L. Christiansen, A. Ealet, L. Faccioli, L. Gladney, G. Kushner, E. Linder, C. Stoughton, L. Wang
Physics
Dome A, the highest plateau in Antarctica, is being developed as a site for an astronomical observatory. The planned telescopes and instrumentation and the unique site characteristics are conducive toward Type Ia supernova surveys for cosmology. A self-contained search and survey over five years can yield a spectro-photometric time series of ∼1000 z < 0.08 supernovae. These can serve to anchor the Hubble diagram and quantify the relationship between luminosities and heterogeneities within the Type Ia supernova class, reducing systematics. Larger aperture (>4-m) telescopes are capable of discovering supernovae shortly after explosion out to z ∼ 3. These can be fed to space telescopes, and can isolate systematics and extend the redshift range over which we measure the expansion history of the universe.
A Grazing Incidence X-Ray Streak Camera For Ultrafast, Single-Shot Measurements, J. Feng, K. Engelhorn, B. I. Cho, H. J. Lee, M. Greaves, Christopher P. Weber, R. W. Falcone, H. A. Padmore, P. A. Heimann
A Grazing Incidence X-Ray Streak Camera For Ultrafast, Single-Shot Measurements, J. Feng, K. Engelhorn, B. I. Cho, H. J. Lee, M. Greaves, Christopher P. Weber, R. W. Falcone, H. A. Padmore, P. A. Heimann
Physics
An ultrafast x-ray streak camera has been realized using a grazing incidence reflection photocathode. X-rays are incident on a gold photocathode at a grazing angle of 20° and photoemitted electrons are focused by a large aperture magnetic solenoid lens. The streak camera has high quantum efficiency, 600 fs temporal resolution, and 6 mm imaging length in the spectral direction. Its single shot capability eliminates temporal smearing due to sweep jitter, and allows recording of the ultrafast dynamics of samples that undergo nonreversible changes.
Characterizing The 410 Km Discontinuity Low‐Velocity Layer Beneath The La Ristra Array In The North American Southwest, John J. Jasbinsek, Ken G. Dueker, Steven M. Hansen
Characterizing The 410 Km Discontinuity Low‐Velocity Layer Beneath The La Ristra Array In The North American Southwest, John J. Jasbinsek, Ken G. Dueker, Steven M. Hansen
Physics
Receiver functions recorded by the 54-station 920 km long Program for Array Seismic Studies of the Continental Lithosphere–Incorporated Research Institutions for Seismology Colorado Plateau/Rio Grande Rift Seismic Transect Experiment (LA RISTRA) line array display a pervasive negative polarity P to S conversion (Pds) arrival preceding the positive polarity 410 km discontinuity arrival. These arrivals are modeled as a low-velocity layer atop the 410 km discontinuity (410-LVL) and are inverted for a velocity profile via a grid search using a five-parameter linear gradient velocity model. Model parameter likelihood and correlations are assessed via calculation of one- and two-dimensional marginal …
Influence Of Functionalized Fullerene Structure On Polymer Photovoltaic Degradation, Brian H. Johnson, Enaanake Allagoa, Robert L. Thomas, Gregory Stettler, Marianne Wallis, Justn H. Peel, Thorsteinn Adalsteinsson, Brian J. Mcnelis, Richard P. Barber Jr.
Influence Of Functionalized Fullerene Structure On Polymer Photovoltaic Degradation, Brian H. Johnson, Enaanake Allagoa, Robert L. Thomas, Gregory Stettler, Marianne Wallis, Justn H. Peel, Thorsteinn Adalsteinsson, Brian J. Mcnelis, Richard P. Barber Jr.
Physics
The time dependence of device performance has been measured for photocells using blends containing the conjugated polymer, poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) with two different functionalized C60 electron acceptor molecules: commercially available [6,6]-phenyl C61 butyric acid methyl ester (PCBM) or [6,6]-phenyl C61 butyric acid octadecyl ester (PCBOD) produced in this laboratory. Performance was characterized by the short-circuit current output of the devices, with the time dependence of PCBM samples typically degrading exponentially. Variations in the characteristic lifetime of the devices were observed to depend on the molar fraction of the electron acceptor molecules (calculated with respect to the MEH-PPV monomer fraction). In comparison …
Sdss J1254+0846: A Binary Quasar Caught In The Act Of Merging, Paul J. Green, Adam D. Myers, Wayne A. Barkhouse, John S. Mulchaey, Vardha N. Bennert, Thomas J. Cox, Thomas L. Aldcroft
Sdss J1254+0846: A Binary Quasar Caught In The Act Of Merging, Paul J. Green, Adam D. Myers, Wayne A. Barkhouse, John S. Mulchaey, Vardha N. Bennert, Thomas J. Cox, Thomas L. Aldcroft
Physics
We present the first luminous, spatially resolved binary quasar that clearly inhabits an ongoing galaxy merger. SDSS J125455.09+084653.9 and SDSS J125454.87+084652.1 (SDSS J1254+0846 hereafter) are two luminous z = 0.44 radio-quiet quasars, with a radial velocity difference of just 215 km s–1, separated on the sky by 21 kpc in a disturbed host galaxy merger showing obvious tidal tails. The pair was targeted as part of a complete sample of binary quasar candidates with small transverse separations drawn from SDSS DR6 photometry. We present follow-up optical imaging which shows broad, symmetrical tidal arm features spanning some 75 kpc …
Analytical Beam Propagation Model For Clipped Focused-Gaussian Beams Using Vector Diffraction Theory, Glen D. Gillen, Christopher M. Seck, Shekhar Guha
Analytical Beam Propagation Model For Clipped Focused-Gaussian Beams Using Vector Diffraction Theory, Glen D. Gillen, Christopher M. Seck, Shekhar Guha
Physics
Vector diffraction theory is applied to the case of focused TEM00 Gaussian beams passing through a spatially limiting aperture in order to investigate the propagation of these clipped focused-Gaussian beams. Beam distributions at different axial distances show that a traditional M2 propagation model cannot be used for the propagation of clipped focus-Gaussian beams. Using Luneberg’s vector diffraction theory and Fresnel approximations, an analytical model for the on-axis transverse and longitudinal electric fields and intensity distributions is presented including predictions of the maximum obtainable intensity. In addition, an analytical expression is provided for the longitudinal component of the electric …
Cosmic Evolution Of Black Holes And Spheroids. Iv. The MBh - LSph Relation, Vardha N. Bennert, Tommaso Treu, Jong-Hak Woo, Matthew A. Malkan, Alexandre Le Bris, Matthew W. Auger, Sarah Gallagher, Roger D. Blandford
Cosmic Evolution Of Black Holes And Spheroids. Iv. The MBh - LSph Relation, Vardha N. Bennert, Tommaso Treu, Jong-Hak Woo, Matthew A. Malkan, Alexandre Le Bris, Matthew W. Auger, Sarah Gallagher, Roger D. Blandford
Physics
From high-resolution images of 23 Seyfert-1 galaxies at z = 0.36 and z = 0.57 obtained with the Near-Infrared Camera and Multi-Object Spectrometer on board the Hubble Space Telescope (HST), we determine host-galaxy morphology, nuclear luminosity, total host-galaxy luminosity, and spheroid luminosity. Keck spectroscopy is used to estimate black hole mass (M BH). We study the cosmic evolution of the M BH-spheroid luminosity (L sph) relation. In combination with our previous work, totaling 40 Seyfert-1 galaxies, the covered range in BH mass is substantially increased, allowing us to determine for the first time …
Review Of Sustainable Energy – Without The Hot Air By David Mackay, David W. Hafemeister
Review Of Sustainable Energy – Without The Hot Air By David Mackay, David W. Hafemeister
Physics
No abstract provided.
Psc 307: Nuclear Proliferation, David Hafemeister
The Longitude Problem From The 1700s To Today: An International And General Education Physics Course, Thomas J. Bensky
The Longitude Problem From The 1700s To Today: An International And General Education Physics Course, Thomas J. Bensky
Physics
For instructors wishing to use physics as part of an international or general education course, the framework for a course based on the “longitude problem” from the 1700s is described. The longitude problem is teeming with basic principles of physics and astronomy, which makes it ideal for a non-science-major-based college-level course. This paper summarizes the longitude problem in the context of conceptual physics and astronomy and outlines an appropriate curriculum. Specifics on teaching such a course in London, as part of an international studies program, are discussed.
Computer-Guided Solutions To Physics Problems Using Prolog, Thomas J. Bensky, Catherine A. Taff
Computer-Guided Solutions To Physics Problems Using Prolog, Thomas J. Bensky, Catherine A. Taff
Physics
By posing a continual stream of pertinent questions, a nonmathematical computer program can prod freshman physics students toward an analytical solution to one-dimensional kinematics problems.
Web-Based Student Data Collection And Assessment, Thomas J. Bensky
Web-Based Student Data Collection And Assessment, Thomas J. Bensky
Physics
Gathering information from students for learning assessment is a critical need of any teacher. In this paper, the tech-savvy instructor is introduced to basic techniques of creating custom, web-based, student-data collection software. Despite widespread deployment of generalized course management systems, the author argues that small, ultra-customized data collection methodologies, can be of great help in collecting and assessing student input, reducing demands on paper, and easing the familiar grading bottleneck while satisfying an individual's pedagogical needs.
Strain Within The Ultrahigh‐Pressure Western Gneiss Region Of Norway Recorded By Quartz Cpos, Nicolas C. Barth, Bradley R. Hacker, Gareth G.E. Seward, Emily O. Walsh, David Young, Scott Johnston
Strain Within The Ultrahigh‐Pressure Western Gneiss Region Of Norway Recorded By Quartz Cpos, Nicolas C. Barth, Bradley R. Hacker, Gareth G.E. Seward, Emily O. Walsh, David Young, Scott Johnston
Physics
Electron back‐scatter diffraction was used to measure the crystal preferred orientations (CPOs) from 101 samples across the ultrahigh‐pressure Western Gneiss Region of Norway to assess slip systems, sense of shear, CPO strength, and strain geometry. The CPOs suggest a dominance of prism slip, with lesser amounts of prism [c] slip and basal slip; there are few Type‐I and Type‐II girdles. The major structural feature in the study area—the high‐strain, top‐W, normal‐sense Nordfjord–Sogn Detachment Zone—is characterized by asymmetric and strong CPOs; an eastern domain with strong asymmetric CPOs shows top‐E shear. Strain throughout the study area was characterized by a mix …
Defining A Standard Metric For Electricity Savings, Jonathan Koomey, Hashem Akbari, Carl Blumstein, Marilyn Brown, Richard Brown, Chris Calwell, Sheryl Carter, Ralph Cavanagh, Audrey Chang, David Claridge, Paul Craig, Rick Diamond, Joseph H. Eto, William Fulkerson, Ashok Gadgil, Howard Geller, José Goldemberg, Chuck Goldman, David B. Goldstein, Steve Greenberg, David W. Hafemeister, Jeff Harris, Hal Harvey, Eric Heitz, Eric Hirst, Holmes Hummel, Dan Kammen, Henry Kelly, Skip Laitner, Mark Levine, Amory Lovins, Gil Masters, James E. Mcmahon, Alan Meier, Michael Messenger, John Millhone, Evan Mills, Steve Nadel, Bruce Nordman, Lynn Price, Joe Romm, Marc Ross, Michael Rufo, Jayant Sathaye, Lee Schipper, Stephen H. Schneider, James L. Sweeney, Malcolm Verdict, Diana Vorsatz, Devra Wang, Carl Weinberg, Richard Wilk, John Wilson, Ernst Worrell
Defining A Standard Metric For Electricity Savings, Jonathan Koomey, Hashem Akbari, Carl Blumstein, Marilyn Brown, Richard Brown, Chris Calwell, Sheryl Carter, Ralph Cavanagh, Audrey Chang, David Claridge, Paul Craig, Rick Diamond, Joseph H. Eto, William Fulkerson, Ashok Gadgil, Howard Geller, José Goldemberg, Chuck Goldman, David B. Goldstein, Steve Greenberg, David W. Hafemeister, Jeff Harris, Hal Harvey, Eric Heitz, Eric Hirst, Holmes Hummel, Dan Kammen, Henry Kelly, Skip Laitner, Mark Levine, Amory Lovins, Gil Masters, James E. Mcmahon, Alan Meier, Michael Messenger, John Millhone, Evan Mills, Steve Nadel, Bruce Nordman, Lynn Price, Joe Romm, Marc Ross, Michael Rufo, Jayant Sathaye, Lee Schipper, Stephen H. Schneider, James L. Sweeney, Malcolm Verdict, Diana Vorsatz, Devra Wang, Carl Weinberg, Richard Wilk, John Wilson, Ernst Worrell
Physics
The growing investment by governments and electric utilities in energy efficiency programs highlights the need for simple tools to help assess and explain the size of the potential resource. One technique that is commonly used in this effort is to characterize electricity savings in terms of avoided power plants, because it is easier for people to visualize a power plant than it is to understand an abstraction such as billions of kilowatt-hours. Unfortunately, there is no standardization around the characteristics of such power plants.
In this letter we define parameters for a standard avoided power plant that have physical meaning …
Psc 307: Nuclear Weapons Arms Control, David Hafemeister
Psc 307: Nuclear Weapons Arms Control, David Hafemeister
Physics
No abstract provided.
The Jets Of Tev Blazars At Higher Resolution: 43 Ghz And Polarimetric Vlba Observations From 2005-2009, B. Glenn Piner, Philip G. Edwards
The Jets Of Tev Blazars At Higher Resolution: 43 Ghz And Polarimetric Vlba Observations From 2005-2009, B. Glenn Piner, Philip G. Edwards
Physics
We present 23 new VLBA images of the six established TeV blazars Markarian 421, Markarian 501, H 1426+428, 1ES 1959+650, PKS 2155-304, and 1ES 2344+514, obtained from 2005 to 2009. Most images were obtained at 43 GHz, and they reveal the parsec-scale structures of three of these sources (1ES 1959+650, PKS 2155-304, and 1ES 2344+514) at factors of two to three higher resolution than has previously been attained. Most of the remaining images map the linear polarization structures at a lower frequency of 22 GHz. We discuss the transverse structures of the jets as revealed by the high-frequency …