Ontology type: schema:Chapter
2007
AUTHORSR. Ojha , A. L. Fey , D. L. Jauncey , J. E. J. Lovell , K. J. Johnston
ABSTRACTExtragalactic radio sources, such as those that define the International Celestial Reference Frame (ICRF), display a variety of structure down to milliarcsecond scales. Further they are all variable on scales of years to weeks. This departure from the point source approximation introduces error in the observable variables (dc-lay and rate). The effect of source structure on Position can be as large as tens of milliarcseconds (e.g. [4]). Also, as the structure of these sources varies with time, it is important to image them at several epochs in order to define a time dependent source model. Multi-epoch observations, using the Very Long Baseline Array (VLBA) to image northern hemisphere sources and the Australian Long Baseline Array (LBA) to image southern hemisphere sources have been progressing successfully for a few years. However, the need for such extensive monitoring programs could be dramatically reduced if a population of extragalactic radio sources that have little or no milliarcsecond scale structure was available.Very Long Baseline Interferometry (VLBI) observations of extragalactic radio sources which exhibit interstellar scintillation suggest that such sources are among the most compact in the sky. In particular, the most variable weak sources, might be the most point-like and, thus, some of the best candidates for densification of the ICRF and consequent improvement in its accuracy. Further, the advent of the MarkV VLBI recording System, with its enhanced sensitivity, will make use of weaker sources easier. We present the evidence for and discuss the viability of this idea which has the potential to revolutionize future Upgrades of the ICRF. More... »
PAGES610-615
Dynamic Planet
ISBN
978-3-540-49349-5
978-3-540-49350-1
http://scigraph.springernature.com/pub.10.1007/978-3-540-49350-1_88
DOIhttp://dx.doi.org/10.1007/978-3-540-49350-1_88
DIMENSIONShttps://app.dimensions.ai/details/publication/pub.1019843218
JSON-LD is the canonical representation for SciGraph data.
TIP: You can open this SciGraph record using an external JSON-LD service: JSON-LD Playground Google SDTT
[
{
"@context": "https://springernature.github.io/scigraph/jsonld/sgcontext.json",
"about": [
{
"id": "http://purl.org/au-research/vocabulary/anzsrc-for/2008/02",
"inDefinedTermSet": "http://purl.org/au-research/vocabulary/anzsrc-for/2008/",
"name": "Physical Sciences",
"type": "DefinedTerm"
},
{
"id": "http://purl.org/au-research/vocabulary/anzsrc-for/2008/0201",
"inDefinedTermSet": "http://purl.org/au-research/vocabulary/anzsrc-for/2008/",
"name": "Astronomical and Space Sciences",
"type": "DefinedTerm"
}
],
"author": [
{
"affiliation": {
"alternateName": "CSIRO, Australia Telescopc National Facility, PO Box 76, 1710, Epping, NSW, Australia",
"id": "http://www.grid.ac/institutes/grid.1016.6",
"name": [
"CSIRO, Australia Telescopc National Facility, PO Box 76, 1710, Epping, NSW, Australia"
],
"type": "Organization"
},
"familyName": "Ojha",
"givenName": "R.",
"id": "sg:person.016513273607.59",
"sameAs": [
"https://app.dimensions.ai/discover/publication?and_facet_researcher=ur.016513273607.59"
],
"type": "Person"
},
{
"affiliation": {
"alternateName": "U.S. Naval Observatory, 3450 Massachusetts Avenuem NW, 20392-5420, Washington, DC, USA",
"id": "http://www.grid.ac/institutes/grid.440354.2",
"name": [
"U.S. Naval Observatory, 3450 Massachusetts Avenuem NW, 20392-5420, Washington, DC, USA"
],
"type": "Organization"
},
"familyName": "Fey",
"givenName": "A. L.",
"id": "sg:person.014337020766.37",
"sameAs": [
"https://app.dimensions.ai/discover/publication?and_facet_researcher=ur.014337020766.37"
],
"type": "Person"
},
{
"affiliation": {
"alternateName": "CSIRO, Australia Telescopc National Facility, PO Box 76, 1710, Epping, NSW, Australia",
"id": "http://www.grid.ac/institutes/grid.1016.6",
"name": [
"CSIRO, Australia Telescopc National Facility, PO Box 76, 1710, Epping, NSW, Australia"
],
"type": "Organization"
},
"familyName": "Jauncey",
"givenName": "D. L.",
"id": "sg:person.011543672245.86",
"sameAs": [
"https://app.dimensions.ai/discover/publication?and_facet_researcher=ur.011543672245.86"
],
"type": "Person"
},
{
"affiliation": {
"alternateName": "CSIRO, Australia Telescopc National Facility, PO Box 76, 1710, Epping, NSW, Australia",
"id": "http://www.grid.ac/institutes/grid.1016.6",
"name": [
"CSIRO, Australia Telescopc National Facility, PO Box 76, 1710, Epping, NSW, Australia"
],
"type": "Organization"
},
"familyName": "Lovell",
"givenName": "J. E. J.",
"id": "sg:person.014733505461.37",
"sameAs": [
"https://app.dimensions.ai/discover/publication?and_facet_researcher=ur.014733505461.37"
],
"type": "Person"
},
{
"affiliation": {
"alternateName": "U.S. Naval Observatory, 3450 Massachusetts Avenuem NW, 20392-5420, Washington, DC, USA",
"id": "http://www.grid.ac/institutes/grid.440354.2",
"name": [
"U.S. Naval Observatory, 3450 Massachusetts Avenuem NW, 20392-5420, Washington, DC, USA"
],
"type": "Organization"
},
"familyName": "Johnston",
"givenName": "K. J.",
"id": "sg:person.013057735753.41",
"sameAs": [
"https://app.dimensions.ai/discover/publication?and_facet_researcher=ur.013057735753.41"
],
"type": "Person"
}
],
"datePublished": "2007",
"datePublishedReg": "2007-01-01",
"description": "Extragalactic radio sources, such as those that define the International Celestial Reference Frame (ICRF), display a variety of structure down to milliarcsecond scales. Further they are all variable on scales of years to weeks. This departure from the point source approximation introduces error in the observable variables (dc-lay and rate). The effect of source structure on Position can be as large as tens of milliarcseconds (e.g. [4]). Also, as the structure of these sources varies with time, it is important to image them at several epochs in order to define a time dependent source model. Multi-epoch observations, using the Very Long Baseline Array (VLBA) to image northern hemisphere sources and the Australian Long Baseline Array (LBA) to image southern hemisphere sources have been progressing successfully for a few years. However, the need for such extensive monitoring programs could be dramatically reduced if a population of extragalactic radio sources that have little or no milliarcsecond scale structure was available.Very Long Baseline Interferometry (VLBI) observations of extragalactic radio sources which exhibit interstellar scintillation suggest that such sources are among the most compact in the sky. In particular, the most variable weak sources, might be the most point-like and, thus, some of the best candidates for densification of the ICRF and consequent improvement in its accuracy. Further, the advent of the MarkV VLBI recording System, with its enhanced sensitivity, will make use of weaker sources easier. We present the evidence for and discuss the viability of this idea which has the potential to revolutionize future Upgrades of the ICRF.",
"editor": [
{
"familyName": "Tregoning",
"givenName": "Paul",
"type": "Person"
},
{
"familyName": "Rizos",
"givenName": "Chris",
"type": "Person"
}
],
"genre": "chapter",
"id": "sg:pub.10.1007/978-3-540-49350-1_88",
"inLanguage": "en",
"isAccessibleForFree": false,
"isPartOf": {
"isbn": [
"978-3-540-49349-5",
"978-3-540-49350-1"
],
"name": "Dynamic Planet",
"type": "Book"
},
"keywords": [
"International Celestial Reference Frame",
"extragalactic radio sources",
"Long Baseline Array",
"Celestial Reference Frame",
"radio sources",
"Australian Long Baseline Array",
"long baseline interferometry (VLBI) observations",
"milliarcsecond scale structure",
"tens of milliarcseconds",
"reference frame",
"multi-epoch observations",
"interstellar scintillation",
"point source approximation",
"weak sources",
"interferometry observations",
"milliarcsecond scales",
"source approximation",
"observable variables",
"scale structure",
"source structure",
"source model",
"approximation",
"variety of structures",
"scintillation",
"such sources",
"milliarcseconds",
"scale of years",
"structure",
"future upgrades",
"error",
"sky",
"array",
"epoch",
"accuracy",
"model",
"southern hemisphere sources",
"variables",
"frame",
"good candidate",
"observations",
"system",
"departure",
"idea",
"order",
"scale",
"source",
"extensive monitoring program",
"tens",
"recording system",
"position",
"northern hemisphere sources",
"upgrade",
"time",
"variety",
"potential",
"advent",
"effect",
"candidates",
"improvement",
"use",
"key",
"consequent improvement",
"sensitivity",
"program",
"monitoring program",
"need",
"densification",
"enhanced sensitivity",
"years",
"population",
"evidence",
"viability",
"weeks"
],
"name": "Is Scintillation the Key to a Better Celestial Reference Frame?",
"pagination": "610-615",
"productId": [
{
"name": "dimensions_id",
"type": "PropertyValue",
"value": [
"pub.1019843218"
]
},
{
"name": "doi",
"type": "PropertyValue",
"value": [
"10.1007/978-3-540-49350-1_88"
]
}
],
"publisher": {
"name": "Springer Nature",
"type": "Organisation"
},
"sameAs": [
"https://doi.org/10.1007/978-3-540-49350-1_88",
"https://app.dimensions.ai/details/publication/pub.1019843218"
],
"sdDataset": "chapters",
"sdDatePublished": "2022-05-20T07:45",
"sdLicense": "https://scigraph.springernature.com/explorer/license/",
"sdPublisher": {
"name": "Springer Nature - SN SciGraph project",
"type": "Organization"
},
"sdSource": "s3://com-springernature-scigraph/baseset/20220519/entities/gbq_results/chapter/chapter_295.jsonl",
"type": "Chapter",
"url": "https://doi.org/10.1007/978-3-540-49350-1_88"
}
]
Download the RDF metadata as: json-ld nt turtle xml License info
JSON-LD is a popular format for linked data which is fully compatible with JSON.
curl -H 'Accept: application/ld+json' 'https://scigraph.springernature.com/pub.10.1007/978-3-540-49350-1_88'
N-Triples is a line-based linked data format ideal for batch operations.
curl -H 'Accept: application/n-triples' 'https://scigraph.springernature.com/pub.10.1007/978-3-540-49350-1_88'
Turtle is a human-readable linked data format.
curl -H 'Accept: text/turtle' 'https://scigraph.springernature.com/pub.10.1007/978-3-540-49350-1_88'
RDF/XML is a standard XML format for linked data.
curl -H 'Accept: application/rdf+xml' 'https://scigraph.springernature.com/pub.10.1007/978-3-540-49350-1_88'
This table displays all metadata directly associated to this object as RDF triples.
169 TRIPLES
23 PREDICATES
99 URIs
92 LITERALS
7 BLANK NODES
Subject | Predicate | Object | |
---|---|---|---|
1 | sg:pub.10.1007/978-3-540-49350-1_88 | schema:about | anzsrc-for:02 |
2 | ″ | ″ | anzsrc-for:0201 |
3 | ″ | schema:author | N4e77be22c40545b0b39284aa15a9847b |
4 | ″ | schema:datePublished | 2007 |
5 | ″ | schema:datePublishedReg | 2007-01-01 |
6 | ″ | schema:description | Extragalactic radio sources, such as those that define the International Celestial Reference Frame (ICRF), display a variety of structure down to milliarcsecond scales. Further they are all variable on scales of years to weeks. This departure from the point source approximation introduces error in the observable variables (dc-lay and rate). The effect of source structure on Position can be as large as tens of milliarcseconds (e.g. [4]). Also, as the structure of these sources varies with time, it is important to image them at several epochs in order to define a time dependent source model. Multi-epoch observations, using the Very Long Baseline Array (VLBA) to image northern hemisphere sources and the Australian Long Baseline Array (LBA) to image southern hemisphere sources have been progressing successfully for a few years. However, the need for such extensive monitoring programs could be dramatically reduced if a population of extragalactic radio sources that have little or no milliarcsecond scale structure was available.Very Long Baseline Interferometry (VLBI) observations of extragalactic radio sources which exhibit interstellar scintillation suggest that such sources are among the most compact in the sky. In particular, the most variable weak sources, might be the most point-like and, thus, some of the best candidates for densification of the ICRF and consequent improvement in its accuracy. Further, the advent of the MarkV VLBI recording System, with its enhanced sensitivity, will make use of weaker sources easier. We present the evidence for and discuss the viability of this idea which has the potential to revolutionize future Upgrades of the ICRF. |
7 | ″ | schema:editor | Nd473d23ec1d04204a5e5ba343698a167 |
8 | ″ | schema:genre | chapter |
9 | ″ | schema:inLanguage | en |
10 | ″ | schema:isAccessibleForFree | false |
11 | ″ | schema:isPartOf | N7739a3b3f73c41b19d6af4c71d585c22 |
12 | ″ | schema:keywords | Australian Long Baseline Array |
13 | ″ | ″ | Celestial Reference Frame |
14 | ″ | ″ | International Celestial Reference Frame |
15 | ″ | ″ | Long Baseline Array |
16 | ″ | ″ | accuracy |
17 | ″ | ″ | advent |
18 | ″ | ″ | approximation |
19 | ″ | ″ | array |
20 | ″ | ″ | candidates |
21 | ″ | ″ | consequent improvement |
22 | ″ | ″ | densification |
23 | ″ | ″ | departure |
24 | ″ | ″ | effect |
25 | ″ | ″ | enhanced sensitivity |
26 | ″ | ″ | epoch |
27 | ″ | ″ | error |
28 | ″ | ″ | evidence |
29 | ″ | ″ | extensive monitoring program |
30 | ″ | ″ | extragalactic radio sources |
31 | ″ | ″ | frame |
32 | ″ | ″ | future upgrades |
33 | ″ | ″ | good candidate |
34 | ″ | ″ | idea |
35 | ″ | ″ | improvement |
36 | ″ | ″ | interferometry observations |
37 | ″ | ″ | interstellar scintillation |
38 | ″ | ″ | key |
39 | ″ | ″ | long baseline interferometry (VLBI) observations |
40 | ″ | ″ | milliarcsecond scale structure |
41 | ″ | ″ | milliarcsecond scales |
42 | ″ | ″ | milliarcseconds |
43 | ″ | ″ | model |
44 | ″ | ″ | monitoring program |
45 | ″ | ″ | multi-epoch observations |
46 | ″ | ″ | need |
47 | ″ | ″ | northern hemisphere sources |
48 | ″ | ″ | observable variables |
49 | ″ | ″ | observations |
50 | ″ | ″ | order |
51 | ″ | ″ | point source approximation |
52 | ″ | ″ | population |
53 | ″ | ″ | position |
54 | ″ | ″ | potential |
55 | ″ | ″ | program |
56 | ″ | ″ | radio sources |
57 | ″ | ″ | recording system |
58 | ″ | ″ | reference frame |
59 | ″ | ″ | scale |
60 | ″ | ″ | scale of years |
61 | ″ | ″ | scale structure |
62 | ″ | ″ | scintillation |
63 | ″ | ″ | sensitivity |
64 | ″ | ″ | sky |
65 | ″ | ″ | source |
66 | ″ | ″ | source approximation |
67 | ″ | ″ | source model |
68 | ″ | ″ | source structure |
69 | ″ | ″ | southern hemisphere sources |
70 | ″ | ″ | structure |
71 | ″ | ″ | such sources |
72 | ″ | ″ | system |
73 | ″ | ″ | tens |
74 | ″ | ″ | tens of milliarcseconds |
75 | ″ | ″ | time |
76 | ″ | ″ | upgrade |
77 | ″ | ″ | use |
78 | ″ | ″ | variables |
79 | ″ | ″ | variety |
80 | ″ | ″ | variety of structures |
81 | ″ | ″ | viability |
82 | ″ | ″ | weak sources |
83 | ″ | ″ | weeks |
84 | ″ | ″ | years |
85 | ″ | schema:name | Is Scintillation the Key to a Better Celestial Reference Frame? |
86 | ″ | schema:pagination | 610-615 |
87 | ″ | schema:productId | N3f09151e33d44947a89a1ce61fd1a67a |
88 | ″ | ″ | Nfffac1140d0049c98288c5d702bb6cea |
89 | ″ | schema:publisher | N1c3fd3b00d574a36a6a8e80cb39e32de |
90 | ″ | schema:sameAs | https://app.dimensions.ai/details/publication/pub.1019843218 |
91 | ″ | ″ | https://doi.org/10.1007/978-3-540-49350-1_88 |
92 | ″ | schema:sdDatePublished | 2022-05-20T07:45 |
93 | ″ | schema:sdLicense | https://scigraph.springernature.com/explorer/license/ |
94 | ″ | schema:sdPublisher | N10cde69bfa774d6eaac0a4d6fec28f63 |
95 | ″ | schema:url | https://doi.org/10.1007/978-3-540-49350-1_88 |
96 | ″ | sgo:license | sg:explorer/license/ |
97 | ″ | sgo:sdDataset | chapters |
98 | ″ | rdf:type | schema:Chapter |
99 | N10cde69bfa774d6eaac0a4d6fec28f63 | schema:name | Springer Nature - SN SciGraph project |
100 | ″ | rdf:type | schema:Organization |
101 | N14c51ddeceba424ca6baf679a0f0e05b | rdf:first | N180298576002491bb541a45ee3eb1413 |
102 | ″ | rdf:rest | rdf:nil |
103 | N180298576002491bb541a45ee3eb1413 | schema:familyName | Rizos |
104 | ″ | schema:givenName | Chris |
105 | ″ | rdf:type | schema:Person |
106 | N1c3fd3b00d574a36a6a8e80cb39e32de | schema:name | Springer Nature |
107 | ″ | rdf:type | schema:Organisation |
108 | N3f09151e33d44947a89a1ce61fd1a67a | schema:name | doi |
109 | ″ | schema:value | 10.1007/978-3-540-49350-1_88 |
110 | ″ | rdf:type | schema:PropertyValue |
111 | N437268f11686433fa61b0f50decf2def | rdf:first | sg:person.014337020766.37 |
112 | ″ | rdf:rest | N913f04a773424b1980dcba77ce04c549 |
113 | N4e77be22c40545b0b39284aa15a9847b | rdf:first | sg:person.016513273607.59 |
114 | ″ | rdf:rest | N437268f11686433fa61b0f50decf2def |
115 | N689255ddb61a4cbe9394997c8f229ab4 | rdf:first | sg:person.014733505461.37 |
116 | ″ | rdf:rest | N8cd620790dcd4ed6b05819133468a740 |
117 | N69c72f371efe4e248f5ae3ac4f635598 | schema:familyName | Tregoning |
118 | ″ | schema:givenName | Paul |
119 | ″ | rdf:type | schema:Person |
120 | N7739a3b3f73c41b19d6af4c71d585c22 | schema:isbn | 978-3-540-49349-5 |
121 | ″ | ″ | 978-3-540-49350-1 |
122 | ″ | schema:name | Dynamic Planet |
123 | ″ | rdf:type | schema:Book |
124 | N8cd620790dcd4ed6b05819133468a740 | rdf:first | sg:person.013057735753.41 |
125 | ″ | rdf:rest | rdf:nil |
126 | N913f04a773424b1980dcba77ce04c549 | rdf:first | sg:person.011543672245.86 |
127 | ″ | rdf:rest | N689255ddb61a4cbe9394997c8f229ab4 |
128 | Nd473d23ec1d04204a5e5ba343698a167 | rdf:first | N69c72f371efe4e248f5ae3ac4f635598 |
129 | ″ | rdf:rest | N14c51ddeceba424ca6baf679a0f0e05b |
130 | Nfffac1140d0049c98288c5d702bb6cea | schema:name | dimensions_id |
131 | ″ | schema:value | pub.1019843218 |
132 | ″ | rdf:type | schema:PropertyValue |
133 | anzsrc-for:02 | schema:inDefinedTermSet | anzsrc-for: |
134 | ″ | schema:name | Physical Sciences |
135 | ″ | rdf:type | schema:DefinedTerm |
136 | anzsrc-for:0201 | schema:inDefinedTermSet | anzsrc-for: |
137 | ″ | schema:name | Astronomical and Space Sciences |
138 | ″ | rdf:type | schema:DefinedTerm |
139 | sg:person.011543672245.86 | schema:affiliation | grid-institutes:grid.1016.6 |
140 | ″ | schema:familyName | Jauncey |
141 | ″ | schema:givenName | D. L. |
142 | ″ | schema:sameAs | https://app.dimensions.ai/discover/publication?and_facet_researcher=ur.011543672245.86 |
143 | ″ | rdf:type | schema:Person |
144 | sg:person.013057735753.41 | schema:affiliation | grid-institutes:grid.440354.2 |
145 | ″ | schema:familyName | Johnston |
146 | ″ | schema:givenName | K. J. |
147 | ″ | schema:sameAs | https://app.dimensions.ai/discover/publication?and_facet_researcher=ur.013057735753.41 |
148 | ″ | rdf:type | schema:Person |
149 | sg:person.014337020766.37 | schema:affiliation | grid-institutes:grid.440354.2 |
150 | ″ | schema:familyName | Fey |
151 | ″ | schema:givenName | A. L. |
152 | ″ | schema:sameAs | https://app.dimensions.ai/discover/publication?and_facet_researcher=ur.014337020766.37 |
153 | ″ | rdf:type | schema:Person |
154 | sg:person.014733505461.37 | schema:affiliation | grid-institutes:grid.1016.6 |
155 | ″ | schema:familyName | Lovell |
156 | ″ | schema:givenName | J. E. J. |
157 | ″ | schema:sameAs | https://app.dimensions.ai/discover/publication?and_facet_researcher=ur.014733505461.37 |
158 | ″ | rdf:type | schema:Person |
159 | sg:person.016513273607.59 | schema:affiliation | grid-institutes:grid.1016.6 |
160 | ″ | schema:familyName | Ojha |
161 | ″ | schema:givenName | R. |
162 | ″ | schema:sameAs | https://app.dimensions.ai/discover/publication?and_facet_researcher=ur.016513273607.59 |
163 | ″ | rdf:type | schema:Person |
164 | grid-institutes:grid.1016.6 | schema:alternateName | CSIRO, Australia Telescopc National Facility, PO Box 76, 1710, Epping, NSW, Australia |
165 | ″ | schema:name | CSIRO, Australia Telescopc National Facility, PO Box 76, 1710, Epping, NSW, Australia |
166 | ″ | rdf:type | schema:Organization |
167 | grid-institutes:grid.440354.2 | schema:alternateName | U.S. Naval Observatory, 3450 Massachusetts Avenuem NW, 20392-5420, Washington, DC, USA |
168 | ″ | schema:name | U.S. Naval Observatory, 3450 Massachusetts Avenuem NW, 20392-5420, Washington, DC, USA |
169 | ″ | rdf:type | schema:Organization |