Results 21 to 30 of about 658,780 (159)

Interstellar Scattering [PDF]

Symposium - International Astronomical Union, 1984
Fine scale electron density fluctuations in the interstellar medium (ISM) are manifest as scintillations and temporal broadening of pulsar signals and as angular broadening of galactic and extragalactic sources. Although scattering off the fluctuations is often a nuisance for conventional studies of radio sources, analysis or searches for interstellar ...
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Interstellar Scattering in the Galactic Anticenter [PDF]

International Astronomical Union Colloquium, 1998
AbstractInterstellar scattering dictates the limiting resolution for many pulsars and OH masers and some extragalactic sources, a limit made more important by the advent of spacebased VLBI. Scattering observations have been biased toward the inner Galaxy, leaving largely unconstrained basic parameters such as the scattering medium’s extent in the outer
T. Joseph W. Lazio, James M. Cordes
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Locating the intense interstellar scattering towards the inner Galaxy [PDF]

, 2017
We use VLBA+VLA observations to measure the sizes of the scatter-broadened images of 6 of the most heavily scattered known pulsars: 3 within the Galactic Centre (GC) and 3 elsewhere in the inner Galactic plane (!l < 20_).
Demorest, P., M. Johnson, Johnson, M., Stappers, Benjamin; id_orcid, Demorest, P, Stappers, B., Kramer, Michael, Spitler, L G, J. Dexter, Stappers, B.W., Lyne, A. G., Bower, G. C., Bower, G., G. C. Bower, Deller, A., M. Kerr, M. Kramer, A. G. Lyne, Kramer, M., Kerr, M., Lyne, A., Lyne, Andrew, Psaltis, D., B.W. Stappers, A. Deller, Dexter, J, Spitler, L. G., Bower, G.C., L. G. Spitler, Spitler, L., Dexter, J., P. Demorest, D. Psaltis, R. Narayan, Narayan, R.   +34 more
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Improving pulsar distances by modelling interstellar scattering [PDF]

Monthly Notices of the Royal Astronomical Society, 1998
We present here a method to study the distribution of electron density fluctuations in pulsar directions as well as to estimate pulsar distances. The method, based on a simple two-component model of the scattering medium discussed by Gwinn et al. (1993), uses scintillation & proper motion data in addition to the measurements of angular broadening ...
Deshpande, A.A., Ramachandran, R.
openaire   +3 more sources

Heating of the low-latitude solar wind by dissipation of turbulent magnetic fluctuations [PDF]

, 2001
We test a theory presented previously to account for the turbulent transport of magnetic fluctuation energy in the solar wind and the related dissipation and heating of the ambient ion population. This theory accounts for the injection of magnetic energy
Matthaeus, William H., Richardson, John D., Oughton, Sean, Smith, Charles W., Ness, Norman F., Zank, Gary P.   +5 more
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The NANOGrav 12.5 year data set: Monitoring interstellar scattering delays

, 2021
We extract interstellar scintillation parameters for pulsars observed by the NANOGrav radio pulsar timing program. Dynamic spectra for the observing epochs of each pulsar were used to obtain estimates of scintillation timescales, scintillation bandwidths,
Lazio, T. Joseph W., Lynch, Ryan S., Demorest, Paul B., Vigeland, Sarah J., Fonseca, Emmanuel, Swiggum, Joseph K., Chatterjee, Shami, McLaughlin, Maura A., Cordes, James M., DeCesar, Megan E., Brook, Paul R., Ransom, Scott M., Pol, Nihan S., Cromartie, H. Thankful, Turner, Jacob E., Ferdman, Robert D., Garver-Daniels, Nathan, Arzoumanian, Zaven, Good, Deborah C., Pennucci, Timothy T., Spiewak, Renée, Ellis, Justin A., Lam, Michael T., Ferrara, Elizabeth C., Gentile, Peter A., Ng, Cherry, Nice, David J., Blumer, Harsha, Shapiro-Albert, Brent J., Jones, Megan L., Stinebring, Daniel R., Dolch, Timothy, Stairs, Ingrid H., Stovall, Kevin, Lorimer, Duncan R., Luo, Jing   +35 more
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Electronic spectroscopy of cold cations in a 22-pole trap by indirect methods [PDF]

, 2013
The confining capabilities of a 22-pole ion trap have been employed to mea- sure electronic spectra of cations of astrophysical relevance. The ion trap sits on the head of a closed cycle cryostat, enabling collisional cooling of the confined ions with
Chakrabarty, Satrajit
core   +1 more source

Interstellar Scattering: Observations and Interpretations [PDF]

International Astronomical Union Colloquium, 1996
Abstract The successful theory for radio propagation through the interstellar plasma is reviewed, where the density spectrum follows the Kolmogorov model. However, there are also several observations indicating more refraction than expected. A particular model of enhanced refraction is proposed in which isolated regions of the warm ionized medium ...
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The Power of the Rings: The GRB 221009A Soft X-Ray Emission from Its Dust-scattering Halo

The Astrophysical Journal Letters, 2023
GRB 221009A is the brightest gamma-ray burst (GRB) ever detected that has occurred at low Galactic latitude. Owing to this exceptional combination, its prompt X-ray emission could be detected for weeks in the form of expanding X-ray rings produced by ...
Andrea Tiengo, Fabio Pintore, Beatrice Vaia, Simone Filippi, Andrea Sacchi, Paolo Esposito, Michela Rigoselli, Sandro Mereghetti, Ruben Salvaterra, Barbara Šiljeg, Andrea Bracco, Željka Bošnjak, Vibor Jelić, Sergio Campana   +13 more
doaj   +1 more source

Speckles in Interstellar Radio-Wave Scattering [PDF]

International Astronomical Union Colloquium, 1991
AbstractObservations of speckles in the scattering disk of the Vela pulsar are presented and speckle techniques for studying and circumventing scattering of radio waves by the turbulent interstellar plasma are discussed. The speckle pattern contains, in a hologrammatic fashion, complete information on the structure of the radio source as well as the ...
K. M. Desai, C. R. Gwinn, J. Reynolds, E. A. King, D. Jauncey, G. Nicholson, C. Flanagan, R.A. Preston, D.L. Jones   +8 more
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