Search Results - "arcsecond"

The Micro-Arcsecond scintillation-induced variability (MASIV) survey. ii the first Four Epochs by Lovell, J., rickett, B., Macquart, Jean-Pierre, Jauncey, J., Bignall, Hayley, Kedziora-Chudczer, L., Ojha, R., Pursimo, T., Dutka, M., Senkbeil, C., Shabala, S.

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The MicroArcsecond Scintillation-Induced Variability (MASIV) Survey: Detection of Angular Broadening at High Redshift? by Pursimo, T., Ojha, R., Jauncey, J., Lovell, J., Dutka, M., Bignall, Hayley, Macquart, Jean-Pierre, rickett, B., Kedziora-Chudczer, L.

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The Micro-Arcsecond Scintillation-Induced Variability (Masiv) Survey. III. Optical Identifications and New Redshifts by Pursimo, T, Ojha, R, Jauncey, David, Rickett, B, Dutka, M, Koay, J, Lovell, J, Bignall, Hayley, Kedziora-Chudczer, L, Macquart, Jean-Pierre

“…The MASIV (The Micro-Arcsecond Scintillation-Induced Variability) survey of 443 flat spectrum sources revealed that the IDV is related to the radio flux density and redshift. …”
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Interplanetary scintillation studies with the Murchison Widefield Array - II. Properties of sub-arcsecond compact sources at low radio frequencies by Chhetri, Rajan, Morgan, John, Ekers, Ronald, Macquart, Jean-Pierre, Sadler, E., Giroletti, M., Callingham, J., Tingay, Steven

“…This powerful technique allows us to identify and measure sub-arcsecond compact components in low-frequency radio sources across large areas of sky without the need for long-baseline interferometry or ionospheric calibration. …”
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Interplanetary Scintillation with the Murchison Widefield Array I: a sub-arcsecond survey over 900 deg2 at 79 and 158 MHz by Morgan, John, Macquart, Jean-Pierre, Ekers, Ronald, Chhetri, Rajan, Tokumaru, M., Manoharan, P., Tremblay, Steven, Bisi, M., Jackson, B.

“…Each of these sources is a known radio source, however only a minority were previously known to contain sub-arcsecond components. We discuss our findings and the prospects they hold for future astrophysical and heliospheric studies.…”
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Interplanetary scintillation studies with the Murchison Widefield Array III: Comparison of source counts and densities for radio sources and their sub-arcsecond components at 162MHz by Chhetri, Rajan, Ekers, Ronald, Morgan, John, Macquart, Jean-Pierre, Franzen, Thomas

“…We calculate densities of potential calibrators brighter than 0.4 Jy at low frequencies and find 0.2 sources per square degrees for point sources, rising to 0.7 sources per square degree if sources with more complex arcsecond structure are included. We extrapolate to estimate 4.6 sources per square degrees at 0.04 Jy. …”
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Astrometric accuracy of snapshot fast radio burst localisations with ASKAP by Day, C.K., Deller, A.T., James, Clancy, Lenc, E., Bhandari, S., Shannon, Ryan, Bannister, K.W.

“…The Australian Square Kilometre Array Pathfinder (ASKAP) has localised 11 FRBs with sub-arcsecond to arcsecond precision, leading to sub-galaxy localisation regions in some cases and those covering much of the host galaxy in others. …”
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Interstellar scintillation, AGN physics and the SKA by Bignall, Hayley, Lovell, J, Rickett, B.J., Macquart, Jean-Pierre, Jauncey, J., Kedziora-Chudczer, L., Ojha, Roopesh, Pursimo, T., Senkbeil, C., Shabala, S., Dutka, M.

“…The effective resolution is two orders of magnitude higher than achievable with very long baseline interferometry. The recent Micro-Arcsecond Scintillation-Induced Variability Survey revealed a reduction in ISS at 4.9 GHz with increasing source redshift, implying either an increase in the apparent angular size of high-redshift radio cores beyond that expected due to a cosmological decrease in brightness, or a decrease in the microarcsecond-scale core dominance towards high redshift. …”
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The MASIV legacy: Surveying AGN intra-day variability at radio wavelengths by Koay, Jun Yi, Macquart, Jean-Pierre, Rickett, B., Bignall, Hayley, Jauncey, D., Pursimo, T., Reynolds, Cormac, Lovell, J., Kedziora-Chudczer, L., Ojha, R.

“…The Micro-arcsecond Scintillation-Induced Variability (MASIV) Survey and its follow-up observations have provided large datasets of AGN intra-day variability (IDV) at radio wavelengths. …”
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Coupled Radio and X-Ray Emission and Evidence for Discrete Ejecta in the Jets of SS 433 by Miller-Jones, James, Migliari, S., Fender, R., Thompson, T., van der Klis, M., Mendez, M.

“…We present five epochs of simultaneous radio (VLA) and X-ray (Chandra) observations of SS 433 to study the relation between the radio and X-ray emission in the arcsecond-scale jets of the source. We detected X-ray emission from the extended jets in only one of the five epochs of observation, indicating that the X-ray reheating mechanism is transient. …”
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The first resolved imaging of milliarcsecond-scale jets in Circinus X-1 by Miller-Jones, James, Moin, Aquib, Tingay, Steven, Reynolds, Cormac, Phillips, C., Tzioumis, A., Fender, R., McCallum, J., Nicolson, G., Tudose, V.

“…The jet position angle is relatively consistent with previous arcsecond-scale imaging with the Australia Telescope Compact Array. …”
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A wider audience: Turning VLBI into a survey instrument by Middelberg, E, Deller, A, Brisken, W, Morgan, John, Norris, R

“…Radio observations using the Very Long Baseline Interferometry (VLBI) technique typically have fields of view of only a few arcseconds, due to the computational problems inherent in imaging larger fields. …”
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Interplanetary Scintillation with the Murchison Widefield Array V: An all-sky survey of compact sources using a modern low-frequency radio telescope by Morgan, John, Macquart, Jean-Pierre, Chhetri, Rajan, Ekers, Ronald, Tingay, Steven, Sadler, E.

“…Finally we analyse the potential of the recently upgraded Murchison Widefield Array and discuss the potential of the Square Kilometre Array-low to use Interplanetary Scintillation to probe sub-mJy flux density levels at sub-arcsecond angular resolution.…”
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Evidence for deceleration in the radio jets of GRS1915+105? by Miller-Jones, James, Rupen, M., Fender, R., Rushton, A., Pooley, G., Spencer, R.

“…We initiated an observing campaign to use all three arrays to attempt to track the motion of the jet knots from the 2006 February outburst of the source, giving us unprecedented simultaneous coverage of all angular scales, from milliarcsecond scales out to arcsecond scales. The derived proper motion, which was dominated by the VLA measurements, was found to be 17.0 mas d-1, demonstrating that there has been no significant permanent change in the properties of the jets since 1994. …”
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Discovery and identification of infrared counterpart candidates of four Galactic centre low mass X-ray binaries by Curran, Peter, Chaty, S., Zurita Heras, J.

“…On the basis of positional coincidence with the arcsecond accurate X-ray positions, we identify unambiguous counterpartcandidates for XTE J1637-498, IGRJ17379-3747, IGRJ17585-3057 and GX9+1.Conclusions. …”
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The evolution of a jet ejection of the ultraluminous X-ray source Holmberg II X-1 by Cseh, D., Miller-Jones, James, Jonker, P., Grisé, F., Paragi, Z., Corbel, S., Falcke, H., Frey, S., Kaaret, P., Körding, E.

“…The 9-GHz VLA data show an arcsecond-scale triple structure of Holmberg II X-1 similar to that seen at lower frequencies. …”
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Interstellar scattering as a cosmological probe by Koay, J., Macquart, Jean-Pierre, Rickett, B., Bignall, H., Lovell, J., Reynolds, C., Jauncey, D., Pursimo, T., Kedziora-Chudczer, L., Ojha, R.

“…We are therefore using interstellar scattering, for the first time, as a cosmological probe at micro-arcsecond scales - achieving an angular resolution two orders of magnitude finer than that of Very Long Baseline Interferometry (VLBI). …”
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The low density and magnetization of a massive galaxy halo exposed by a fast radio burst by Prochaska, J.X., Macquart, Jean-Pierre, McQuinn, M., Simha, S., Shannon, Ryan, Day, C.K., Marnoch, L., Ryder, S., Deller, A., Bannister, K.W., Bhandari, S., Bordoloi, R., Bunton, J., Cho, H., Flynn, C., Mahony, E.K., Phillips, C., Qiu, H., Tejos, N.

“…We report the detection of a fast radio burst (FRB 181112), localized with arcsecond precision, that passes through the halo of a foreground galaxy. …”
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Soil and landscape grid of Australia by Grundy, M., Viscarra Rossel, Raphael, Searle, R., Wilson, P., Chen, C., Gregory, L.

“…Landscape attributes at 1 and 3 arcseconds are useful for a wide spectrum of ecological, hydrological and broader environmental applications. …”
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Wide-field VLBI observations of M31: A unique probe of the ionized interstellar medium of a nearby galaxy by Morgan, John S., Argo, Megan K., Trott, Cathryn M., Macquart, Jean-Pierre, Deller, Adam, Middelberg, Enno, Miller-Jones, James, Tingay, Steven J.

“…We classify all 16 as background active galactic nuclei based on their X-ray properties and arcsecond- and mas-scale morphology. The detected sources were then analyzed for evidence of scatter-broadening due to the ionized interstellar medium (ISM) of M31. …”
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