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Full-Text Articles in Physics
Multiwavelength Monitoring Of The Narrow-Line Seyfert 1 Galaxy Arakelian 564. Iii. Optical Observations And The Optical--Uv--X-Ray Connection, O. Shemmer, P. Romano, R. Bertram, W. Brinkmann, S. Collier, K. A. Crowley, E. Detsis, A. V. Filippenko, C. Martin Gaskell, T. A. George, M. Gliozzi, M. E. Hiller, T. L. Jewell, Shai Kaspi, Elizabeth S. Klimek, M. H. Lannon, W D. Li, P. Martini, Smita Mathur, H. Negoro, Hagai Netzer, Iossif Papadakis, Ioannis Papamastorakis, Bradley M. Peterson, Bradley W. Peterson, Richard William Pogge, V. I. Pronik, Kenneth S. Rumstay, S. G. Sergeev, G. M. Stirpe, C. J. Taylor, R. R. Treffers, T. J. Turner, P. Uttley, Marianne Vestergaard, Kaspar Von Braun, R. M. Wagner, Z. Zheng
Multiwavelength Monitoring Of The Narrow-Line Seyfert 1 Galaxy Arakelian 564. Iii. Optical Observations And The Optical--Uv--X-Ray Connection, O. Shemmer, P. Romano, R. Bertram, W. Brinkmann, S. Collier, K. A. Crowley, E. Detsis, A. V. Filippenko, C. Martin Gaskell, T. A. George, M. Gliozzi, M. E. Hiller, T. L. Jewell, Shai Kaspi, Elizabeth S. Klimek, M. H. Lannon, W D. Li, P. Martini, Smita Mathur, H. Negoro, Hagai Netzer, Iossif Papadakis, Ioannis Papamastorakis, Bradley M. Peterson, Bradley W. Peterson, Richard William Pogge, V. I. Pronik, Kenneth S. Rumstay, S. G. Sergeev, G. M. Stirpe, C. J. Taylor, R. R. Treffers, T. J. Turner, P. Uttley, Marianne Vestergaard, Kaspar Von Braun, R. M. Wagner, Z. Zheng
Department of Physics and Astronomy: Faculty Publications
We present the results of a 2 yr long optical monitoring program of the narrow-line Seyfert 1 galaxy Ark 564. The majority of this monitoring project was also covered by X-ray observations (RXT E), and for a period of ~50 days, we observed the galaxy in UV (HST) and X-rays (RXTE and ASCA) simultaneously with the ground-based observations. Rapid and large-amplitude variations seen in the X-ray band, on a daily and hourly timescale, were not detected at optical and UV wavelengths, which in turn exhibited much lower variability either on short (1 day) or long (several months) timescales. The only …
Observation Of The Kapitza-Dirac Effect, Daniel L. Freimund, Kayvan Aflatooni, Herman Batelaan
Observation Of The Kapitza-Dirac Effect, Daniel L. Freimund, Kayvan Aflatooni, Herman Batelaan
Department of Physics and Astronomy: Faculty Publications
In their famous 1927 experiment, Davisson and Germer observed the diffraction of electrons by a periodic material structure, so showing that electrons can behave like waves. Shortly afterwards, Kapitza and Dirac predicted that electrons should also be diffracted by a standing light wave. This Kapitza-Dirac effect is analogous to the diffraction of light by a grating, but with the roles of the wave and matter reversed. The electron and the light grating interact extremely weakly, via the ‘ponderomotive potential,’ so attempts to measure the Kapitza-Dirac effect had to wait for the development of the laser. The idea that the underlying …
A Spectroscopic And Photometric Study Of Short-Timescale Variability In Ngc 5548, M. Dietrich, C. F. Bender, D. J. Bergmann, T. E. Bills, N. G. Bochkarev, A. Burenkov, C. Martin Gaskell, D. D. Gutzmer, R. Grove, M. E. Hiller, J. P. Huchra, Elizabeth S. Klimek, C. Lund, Nelly I. Merkulova, S. Pebley, Matt Poulsen, V. I. Pronik, S. G. Sergeev, E. A. Sergeeva, A. I. Shapovalova, V. V. Vlasyuk, Belinda J. Wilkes
A Spectroscopic And Photometric Study Of Short-Timescale Variability In Ngc 5548, M. Dietrich, C. F. Bender, D. J. Bergmann, T. E. Bills, N. G. Bochkarev, A. Burenkov, C. Martin Gaskell, D. D. Gutzmer, R. Grove, M. E. Hiller, J. P. Huchra, Elizabeth S. Klimek, C. Lund, Nelly I. Merkulova, S. Pebley, Matt Poulsen, V. I. Pronik, S. G. Sergeev, E. A. Sergeeva, A. I. Shapovalova, V. V. Vlasyuk, Belinda J. Wilkes
Department of Physics and Astronomy: Faculty Publications
Results of a ground-based optical monitoring campaign on NGC 5548 in June 1998 are presented. The broad-band fluxes (U, B, V), and the spectrophotometric optical continuum flux Fλ (5100 Å) monotonically decreased in flux while the broad-band R and I fluxes and the integrated emission-line fluxes of Hα and Hβ remained constant to within 5% . On June 22, a short continuum flare was detected in the broad band fluxes. It had an amplitude of about ~18% and it lasted only ≈90 min. The broad band fluxes and the optical continuum Fλ (5100 Å) appear to …