Measurement of TeV gamma-ray spectra with the Cherenkov imaging technique
Identifieur interne : 000795 ( Main/Corpus ); précédent : 000794; suivant : 000796Measurement of TeV gamma-ray spectra with the Cherenkov imaging technique
Auteurs : G. Mohanty ; S. Biller ; D. A. Carter-Lewis ; D. J. Fegan ; A. M. Hillas ; R. C. Lamb ; T. C. Weekes ; M. West ; J. ZweerinkSource :
- Astroparticle Physics [ 0927-6505 ] ; 1998.
Abstract
In this paper, we seek to establish reliable methods for extracting energy spectra for TeV gamma-ray sources observed using the atmospheric Cherenkov Imaging Technique. Careful attention has been paid to the calculation of the telescope gain, and we obtain good agreement between direct measurements, with a statistical error of about 10%, and an absolute calibration from the background cosmic-ray trigger rate that has an overall error of 18%. Two independent analyses that are based on different Monte Carlo shower simulations, employ different selection criteria in order to retain a large fraction of gamma-ray events, and use different approaches to spectral estimation are presented here. The first is a fairly traditional method that builds on established image selection techniques and calculates the detector collection area and an energy estimation function. The error in measuring the enrgy of a single event is estimated at 36%, and we try to compensate for this poor energy resolution. The second analysis uses more elegant gamma-ray selection criteria and implicity incorporates the properties of the detector into the simulations that are then compared with the data in order to obtain source spectra. The two simulations are compared to each other and to the data, with the aim of establishing that each method is robust and insensitive to simulation details. Finally, we consider the main sources of systematic errors, the largest of which is in the telescope gain calibration, arising from an incomplete knowledge of the relevant factors, and is estimated to be 16%. The effect of possible errors in the simulations is also considered. Both methods have been applied to a part of the Whipple observatory database on the Crab Nebula for the 1988/89 observing season, while the first method has also been applied to data taken in 1995/96. The statistical error in the flux constant is about 8% and that in the spectral index is about 5%, while the corresponding systematic errors are estimated to be 18% and 2%, respectively. The results presented here show good agreement between the two methods as well as between the two seasons. However, a comprehensive consideration of the implications of the derived spectra and a comparison to other work is addressed in another paper.
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DOI: 10.1016/S0927-6505(98)00005-X
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Mohanty</name><affiliation><mods:affiliation>Department of Physics and Astronomy, Iowa State University, Ames, IA 50011-3160, USA</mods:affiliation></affiliation><affiliation><mods:affiliation>Presently at LPNHE Ecole Polytechnique, 91128 Palaiseau Cedex, France</mods:affiliation></affiliation></author><author><name sortKey="Biller, S" sort="Biller, S" uniqKey="Biller S" first="S." last="Biller">S. Biller</name><affiliation><mods:affiliation>Department of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK</mods:affiliation></affiliation></author><author><name sortKey="Carter Lewis, D A" sort="Carter Lewis, D A" uniqKey="Carter Lewis D" first="D. A." last="Carter-Lewis">D. A. Carter-Lewis</name><affiliation><mods:affiliation>Department of Physics and Astronomy, Iowa State University, Ames, IA 50011-3160, USA</mods:affiliation></affiliation></author><author><name sortKey="Fegan, D J" sort="Fegan, D J" uniqKey="Fegan D" first="D. J." last="Fegan">D. J. Fegan</name><affiliation><mods:affiliation>Physics Department, University College Dublin, Dublin, Ireland</mods:affiliation></affiliation></author><author><name sortKey="Hillas, A M" sort="Hillas, A M" uniqKey="Hillas A" first="A. M." last="Hillas">A. M. Hillas</name><affiliation><mods:affiliation>Department of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK</mods:affiliation></affiliation></author><author><name sortKey="Lamb, R C" sort="Lamb, R C" uniqKey="Lamb R" first="R. C." last="Lamb">R. C. Lamb</name><affiliation><mods:affiliation>Space Radiation Laboratory, Caltech, Pasadena, CAUSA</mods:affiliation></affiliation></author><author><name sortKey="Weekes, T C" sort="Weekes, T C" uniqKey="Weekes T" first="T. C." last="Weekes">T. C. Weekes</name><affiliation><mods:affiliation>Harvard-Smithsonian CfA, Fred Lawrence Whipple Observatory, P.O. 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Zweerink</name><affiliation><mods:affiliation>Department of Physics and Astronomy, Iowa State University, Ames, IA 50011-3160, USA</mods:affiliation></affiliation></author></analytic><monogr></monogr><series><title level="j">Astroparticle Physics</title><title level="j" type="abbrev">ASTPHY</title><idno type="ISSN">0927-6505</idno><imprint><publisher>ELSEVIER</publisher><date type="published" when="1998">1998</date><biblScope unit="volume">9</biblScope><biblScope unit="issue">1</biblScope><biblScope unit="page" from="15">15</biblScope><biblScope unit="page" to="43">43</biblScope></imprint><idno type="ISSN">0927-6505</idno></series><idno type="istex">17B1B5B75052F3B686A5BA49D15C4702C83056D2</idno><idno type="DOI">10.1016/S0927-6505(98)00005-X</idno><idno type="PII">S0927-6505(98)00005-X</idno></biblStruct></sourceDesc><seriesStmt><idno type="ISSN">0927-6505</idno></seriesStmt></fileDesc><profileDesc><textClass></textClass><langUsage><language ident="en">en</language></langUsage></profileDesc></teiHeader><front><div type="abstract" xml:lang="en">In this paper, we seek to establish reliable methods for extracting energy spectra for TeV gamma-ray sources observed using the atmospheric Cherenkov Imaging Technique. Careful attention has been paid to the calculation of the telescope gain, and we obtain good agreement between direct measurements, with a statistical error of about 10%, and an absolute calibration from the background cosmic-ray trigger rate that has an overall error of 18%. Two independent analyses that are based on different Monte Carlo shower simulations, employ different selection criteria in order to retain a large fraction of gamma-ray events, and use different approaches to spectral estimation are presented here. The first is a fairly traditional method that builds on established image selection techniques and calculates the detector collection area and an energy estimation function. The error in measuring the enrgy of a single event is estimated at 36%, and we try to compensate for this poor energy resolution. The second analysis uses more elegant gamma-ray selection criteria and implicity incorporates the properties of the detector into the simulations that are then compared with the data in order to obtain source spectra. The two simulations are compared to each other and to the data, with the aim of establishing that each method is robust and insensitive to simulation details. Finally, we consider the main sources of systematic errors, the largest of which is in the telescope gain calibration, arising from an incomplete knowledge of the relevant factors, and is estimated to be 16%. The effect of possible errors in the simulations is also considered. Both methods have been applied to a part of the Whipple observatory database on the Crab Nebula for the 1988/89 observing season, while the first method has also been applied to data taken in 1995/96. The statistical error in the flux constant is about 8% and that in the spectral index is about 5%, while the corresponding systematic errors are estimated to be 18% and 2%, respectively. The results presented here show good agreement between the two methods as well as between the two seasons. However, a comprehensive consideration of the implications of the derived spectra and a comparison to other work is addressed in another paper.</div></front></TEI><istex><corpusName>elsevier</corpusName><author><json:item><name>G. Mohanty</name><affiliations><json:string>Department of Physics and Astronomy, Iowa State University, Ames, IA 50011-3160, USA</json:string><json:string>Presently at LPNHE Ecole Polytechnique, 91128 Palaiseau Cedex, France</json:string></affiliations></json:item><json:item><name>S. Biller</name><affiliations><json:string>Department of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK</json:string></affiliations></json:item><json:item><name>D.A. 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Careful attention has been paid to the calculation of the telescope gain, and we obtain good agreement between direct measurements, with a statistical error of about 10%, and an absolute calibration from the background cosmic-ray trigger rate that has an overall error of 18%. Two independent analyses that are based on different Monte Carlo shower simulations, employ different selection criteria in order to retain a large fraction of gamma-ray events, and use different approaches to spectral estimation are presented here. The first is a fairly traditional method that builds on established image selection techniques and calculates the detector collection area and an energy estimation function. The error in measuring the enrgy of a single event is estimated at 36%, and we try to compensate for this poor energy resolution. The second analysis uses more elegant gamma-ray selection criteria and implicity incorporates the properties of the detector into the simulations that are then compared with the data in order to obtain source spectra. The two simulations are compared to each other and to the data, with the aim of establishing that each method is robust and insensitive to simulation details. Finally, we consider the main sources of systematic errors, the largest of which is in the telescope gain calibration, arising from an incomplete knowledge of the relevant factors, and is estimated to be 16%. The effect of possible errors in the simulations is also considered. Both methods have been applied to a part of the Whipple observatory database on the Crab Nebula for the 1988/89 observing season, while the first method has also been applied to data taken in 1995/96. The statistical error in the flux constant is about 8% and that in the spectral index is about 5%, while the corresponding systematic errors are estimated to be 18% and 2%, respectively. The results presented here show good agreement between the two methods as well as between the two seasons. 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Box 97, Amado, Arizona 85645-0097, USA</affiliation></author><author xml:id="author-8"><persName><forename type="first">M.</forename><surname>West</surname></persName><affiliation>Department of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK</affiliation></author><author xml:id="author-9"><persName><forename type="first">J.</forename><surname>Zweerink</surname></persName><affiliation>Department of Physics and Astronomy, Iowa State University, Ames, IA 50011-3160, USA</affiliation></author></analytic><monogr><title level="j">Astroparticle Physics</title><title level="j" type="abbrev">ASTPHY</title><idno type="pISSN">0927-6505</idno><idno type="PII">S0927-6505(00)X0014-X</idno><imprint><publisher>ELSEVIER</publisher><date type="published" when="1998"></date><biblScope unit="volume">9</biblScope><biblScope unit="issue">1</biblScope><biblScope unit="page" from="15">15</biblScope><biblScope unit="page" to="43">43</biblScope></imprint></monogr><idno type="istex">17B1B5B75052F3B686A5BA49D15C4702C83056D2</idno><idno type="DOI">10.1016/S0927-6505(98)00005-X</idno><idno type="PII">S0927-6505(98)00005-X</idno></biblStruct></sourceDesc></fileDesc><profileDesc><creation><date>1998</date></creation><langUsage><language ident="en">en</language></langUsage><abstract xml:lang="en"><p>In this paper, we seek to establish reliable methods for extracting energy spectra for TeV gamma-ray sources observed using the atmospheric Cherenkov Imaging Technique. Careful attention has been paid to the calculation of the telescope gain, and we obtain good agreement between direct measurements, with a statistical error of about 10%, and an absolute calibration from the background cosmic-ray trigger rate that has an overall error of 18%. Two independent analyses that are based on different Monte Carlo shower simulations, employ different selection criteria in order to retain a large fraction of gamma-ray events, and use different approaches to spectral estimation are presented here. The first is a fairly traditional method that builds on established image selection techniques and calculates the detector collection area and an energy estimation function. The error in measuring the enrgy of a single event is estimated at 36%, and we try to compensate for this poor energy resolution. The second analysis uses more elegant gamma-ray selection criteria and implicity incorporates the properties of the detector into the simulations that are then compared with the data in order to obtain source spectra. The two simulations are compared to each other and to the data, with the aim of establishing that each method is robust and insensitive to simulation details. Finally, we consider the main sources of systematic errors, the largest of which is in the telescope gain calibration, arising from an incomplete knowledge of the relevant factors, and is estimated to be 16%. The effect of possible errors in the simulations is also considered. Both methods have been applied to a part of the Whipple observatory database on the Crab Nebula for the 1988/89 observing season, while the first method has also been applied to data taken in 1995/96. The statistical error in the flux constant is about 8% and that in the spectral index is about 5%, while the corresponding systematic errors are estimated to be 18% and 2%, respectively. The results presented here show good agreement between the two methods as well as between the two seasons. However, a comprehensive consideration of the implications of the derived spectra and a comparison to other work is addressed in another paper.</p></abstract><textClass><keywords scheme="keyword"><list><head>Keywords</head><item><term>Gamma rays</term></item><item><term>General stars</term></item><item><term>Individual (Crab Nebula)</term></item></list></keywords></textClass></profileDesc><revisionDesc><change when="1998-01-06">Modified</change><change when="1998">Published</change></revisionDesc></teiHeader></istex:fulltextTEI><json:item><original>false</original><mimetype>text/plain</mimetype><extension>txt</extension><uri>https://api.istex.fr/document/17B1B5B75052F3B686A5BA49D15C4702C83056D2/fulltext/txt</uri></json:item></fulltext><metadata><istex:metadataXml wicri:clean="Elsevier, elements deleted: tail"><istex:xmlDeclaration>version="1.0" encoding="utf-8"</istex:xmlDeclaration><istex:docType PUBLIC="-//ES//DTD journal article DTD version 4.5.2//EN//XML" URI="art452.dtd" name="istex:docType"></istex:docType><istex:document><converted-article version="4.5.2" docsubtype="fla"><item-info><jid>ASTPHY</jid><aid>9800005X</aid><ce:pii>S0927-6505(98)00005-X</ce:pii><ce:doi>10.1016/S0927-6505(98)00005-X</ce:doi><ce:copyright type="unknown" year="1998"></ce:copyright></item-info><head><ce:title>Measurement of TeV gamma-ray spectra with the Cherenkov imaging technique</ce:title><ce:author-group><ce:author><ce:given-name>G.</ce:given-name><ce:surname>Mohanty</ce:surname><ce:cross-ref refid="AFF1"><ce:sup>a</ce:sup></ce:cross-ref><ce:cross-ref refid="AFF6"><ce:sup>f</ce:sup></ce:cross-ref></ce:author><ce:author><ce:given-name>S.</ce:given-name><ce:surname>Biller</ce:surname><ce:cross-ref refid="AFF2"><ce:sup>b</ce:sup></ce:cross-ref></ce:author><ce:author><ce:given-name>D.A.</ce:given-name><ce:surname>Carter-Lewis</ce:surname><ce:cross-ref refid="AFF1"><ce:sup>a</ce:sup></ce:cross-ref></ce:author><ce:author><ce:given-name>D.J.</ce:given-name><ce:surname>Fegan</ce:surname><ce:cross-ref refid="AFF4"><ce:sup>d</ce:sup></ce:cross-ref></ce:author><ce:author><ce:given-name>A.M.</ce:given-name><ce:surname>Hillas</ce:surname><ce:cross-ref refid="AFF2"><ce:sup>b</ce:sup></ce:cross-ref></ce:author><ce:author><ce:given-name>R.C.</ce:given-name><ce:surname>Lamb</ce:surname><ce:cross-ref refid="AFF3"><ce:sup>c</ce:sup></ce:cross-ref></ce:author><ce:author><ce:given-name>T.C.</ce:given-name><ce:surname>Weekes</ce:surname><ce:cross-ref refid="AFF5"><ce:sup>e</ce:sup></ce:cross-ref></ce:author><ce:author><ce:given-name>M.</ce:given-name><ce:surname>West</ce:surname><ce:cross-ref refid="AFF2"><ce:sup>b</ce:sup></ce:cross-ref></ce:author><ce:author><ce:given-name>J.</ce:given-name><ce:surname>Zweerink</ce:surname><ce:cross-ref refid="AFF1"><ce:sup>a</ce:sup></ce:cross-ref></ce:author><ce:affiliation id="AFF1"><ce:label>a</ce:label><ce:textfn>Department of Physics and Astronomy, Iowa State University, Ames, IA 50011-3160, USA</ce:textfn></ce:affiliation><ce:affiliation id="AFF2"><ce:label>b</ce:label><ce:textfn>Department of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK</ce:textfn></ce:affiliation><ce:affiliation id="AFF3"><ce:label>c</ce:label><ce:textfn>Space Radiation Laboratory, Caltech, Pasadena, CAUSA</ce:textfn></ce:affiliation><ce:affiliation id="AFF4"><ce:label>d</ce:label><ce:textfn>Physics Department, University College Dublin, Dublin, Ireland</ce:textfn></ce:affiliation><ce:affiliation id="AFF5"><ce:label>e</ce:label><ce:textfn>Harvard-Smithsonian CfA, Fred Lawrence Whipple Observatory, P.O. Box 97, Amado, Arizona 85645-0097, USA</ce:textfn></ce:affiliation><ce:affiliation id="AFF6"><ce:label>f</ce:label><ce:textfn>Presently at LPNHE Ecole Polytechnique, 91128 Palaiseau Cedex, France</ce:textfn></ce:affiliation></ce:author-group><ce:date-received day="20" month="5" year="1997"></ce:date-received><ce:date-revised day="6" month="1" year="1998"></ce:date-revised><ce:date-accepted day="17" month="1" year="1998"></ce:date-accepted><ce:abstract><ce:section-title>Abstract</ce:section-title><ce:abstract-sec><ce:simple-para>In this paper, we seek to establish reliable methods for extracting energy spectra for TeV gamma-ray sources observed using the atmospheric Cherenkov Imaging Technique. Careful attention has been paid to the calculation of the telescope gain, and we obtain good agreement between direct measurements, with a statistical error of about 10%, and an absolute calibration from the background cosmic-ray trigger rate that has an overall error of 18%. Two independent analyses that are based on different Monte Carlo shower simulations, employ different selection criteria in order to retain a large fraction of gamma-ray events, and use different approaches to spectral estimation are presented here. The first is a fairly traditional method that builds on established image selection techniques and calculates the detector collection area and an energy estimation function. The error in measuring the enrgy of a single event is estimated at 36%, and we try to compensate for this poor energy resolution. The second analysis uses more elegant gamma-ray selection criteria and implicity incorporates the properties of the detector into the simulations that are then compared with the data in order to obtain source spectra. The two simulations are compared to each other and to the data, with the aim of establishing that each method is robust and insensitive to simulation details. Finally, we consider the main sources of systematic errors, the largest of which is in the telescope gain calibration, arising from an incomplete knowledge of the relevant factors, and is estimated to be 16%. The effect of possible errors in the simulations is also considered.</ce:simple-para><ce:simple-para>Both methods have been applied to a part of the Whipple observatory database on the Crab Nebula for the 1988/89 observing season, while the first method has also been applied to data taken in 1995/96. The statistical error in the flux constant is about 8% and that in the spectral index is about 5%, while the corresponding systematic errors are estimated to be 18% and 2%, respectively. The results presented here show good agreement between the two methods as well as between the two seasons. However, a comprehensive consideration of the implications of the derived spectra and a comparison to other work is addressed in another paper.</ce:simple-para></ce:abstract-sec></ce:abstract><ce:keywords><ce:section-title>Keywords</ce:section-title><ce:keyword><ce:text>Gamma rays</ce:text></ce:keyword><ce:keyword><ce:text>General stars</ce:text></ce:keyword><ce:keyword><ce:text>Individual (Crab Nebula)</ce:text></ce:keyword></ce:keywords></head></converted-article></istex:document></istex:metadataXml><mods version="3.6"><titleInfo><title>Measurement of TeV gamma-ray spectra with the Cherenkov imaging technique</title></titleInfo><titleInfo type="alternative" contentType="CDATA"><title>Measurement of TeV gamma-ray spectra with the Cherenkov imaging technique</title></titleInfo><name type="personal"><namePart type="given">G.</namePart><namePart type="family">Mohanty</namePart><affiliation>Department of Physics and Astronomy, Iowa State University, Ames, IA 50011-3160, USA</affiliation><affiliation>Presently at LPNHE Ecole Polytechnique, 91128 Palaiseau Cedex, France</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">S.</namePart><namePart type="family">Biller</namePart><affiliation>Department of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">D.A.</namePart><namePart type="family">Carter-Lewis</namePart><affiliation>Department of Physics and Astronomy, Iowa State University, Ames, IA 50011-3160, USA</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">D.J.</namePart><namePart type="family">Fegan</namePart><affiliation>Physics Department, University College Dublin, Dublin, Ireland</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">A.M.</namePart><namePart type="family">Hillas</namePart><affiliation>Department of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">R.C.</namePart><namePart type="family">Lamb</namePart><affiliation>Space Radiation Laboratory, Caltech, Pasadena, CAUSA</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">T.C.</namePart><namePart type="family">Weekes</namePart><affiliation>Harvard-Smithsonian CfA, Fred Lawrence Whipple Observatory, P.O. Box 97, Amado, Arizona 85645-0097, USA</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">M.</namePart><namePart type="family">West</namePart><affiliation>Department of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">J.</namePart><namePart type="family">Zweerink</namePart><affiliation>Department of Physics and Astronomy, Iowa State University, Ames, IA 50011-3160, USA</affiliation><role><roleTerm type="text">author</roleTerm></role></name><typeOfResource>text</typeOfResource><genre type="research-article" displayLabel="Full-length article"></genre><originInfo><publisher>ELSEVIER</publisher><dateIssued encoding="w3cdtf">1998</dateIssued><dateModified encoding="w3cdtf">1998-01-06</dateModified><copyrightDate encoding="w3cdtf">1998</copyrightDate></originInfo><language><languageTerm type="code" authority="iso639-2b">eng</languageTerm><languageTerm type="code" authority="rfc3066">en</languageTerm></language><physicalDescription><internetMediaType>text/html</internetMediaType></physicalDescription><abstract lang="en">In this paper, we seek to establish reliable methods for extracting energy spectra for TeV gamma-ray sources observed using the atmospheric Cherenkov Imaging Technique. Careful attention has been paid to the calculation of the telescope gain, and we obtain good agreement between direct measurements, with a statistical error of about 10%, and an absolute calibration from the background cosmic-ray trigger rate that has an overall error of 18%. Two independent analyses that are based on different Monte Carlo shower simulations, employ different selection criteria in order to retain a large fraction of gamma-ray events, and use different approaches to spectral estimation are presented here. The first is a fairly traditional method that builds on established image selection techniques and calculates the detector collection area and an energy estimation function. The error in measuring the enrgy of a single event is estimated at 36%, and we try to compensate for this poor energy resolution. The second analysis uses more elegant gamma-ray selection criteria and implicity incorporates the properties of the detector into the simulations that are then compared with the data in order to obtain source spectra. The two simulations are compared to each other and to the data, with the aim of establishing that each method is robust and insensitive to simulation details. Finally, we consider the main sources of systematic errors, the largest of which is in the telescope gain calibration, arising from an incomplete knowledge of the relevant factors, and is estimated to be 16%. The effect of possible errors in the simulations is also considered. Both methods have been applied to a part of the Whipple observatory database on the Crab Nebula for the 1988/89 observing season, while the first method has also been applied to data taken in 1995/96. The statistical error in the flux constant is about 8% and that in the spectral index is about 5%, while the corresponding systematic errors are estimated to be 18% and 2%, respectively. The results presented here show good agreement between the two methods as well as between the two seasons. However, a comprehensive consideration of the implications of the derived spectra and a comparison to other work is addressed in another paper.</abstract><subject><genre>Keywords</genre><topic>Gamma rays</topic><topic>General stars</topic><topic>Individual (Crab Nebula)</topic></subject><relatedItem type="host"><titleInfo><title>Astroparticle Physics</title></titleInfo><titleInfo type="abbreviated"><title>ASTPHY</title></titleInfo><genre type="journal">journal</genre><originInfo><dateIssued encoding="w3cdtf">199806</dateIssued></originInfo><identifier type="ISSN">0927-6505</identifier><identifier type="PII">S0927-6505(00)X0014-X</identifier><part><date>199806</date><detail type="volume"><number>9</number><caption>vol.</caption></detail><detail type="issue"><number>1</number><caption>no.</caption></detail><extent unit="issue pages"><start>1</start><end>103</end></extent><extent unit="pages"><start>15</start><end>43</end></extent></part></relatedItem><identifier type="istex">17B1B5B75052F3B686A5BA49D15C4702C83056D2</identifier><identifier type="DOI">10.1016/S0927-6505(98)00005-X</identifier><identifier type="PII">S0927-6505(98)00005-X</identifier><recordInfo><recordContentSource>ELSEVIER</recordContentSource></recordInfo></mods></metadata><enrichments><istex:catWosTEI uri="https://api.istex.fr/document/17B1B5B75052F3B686A5BA49D15C4702C83056D2/enrichments/catWos"><teiHeader><profileDesc><textClass><classCode scheme="WOS">ASTRONOMY & ASTROPHYSICS</classCode><classCode scheme="WOS">PHYSICS, PARTICLES & FIELDS</classCode></textClass></profileDesc></teiHeader></istex:catWosTEI></enrichments></istex></record>Pour manipuler ce document sous Unix (Dilib)
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