@prefix pubblicazioni: . @prefix unitaDiPersonaleInterno: . @prefix prodotto: . unitaDiPersonaleInterno:MATRICOLA12320 pubblicazioni:autoreCNRDi prodotto:ID5616 . @prefix rdf: . @prefix retescientifica: . prodotto:ID5616 rdf:type retescientifica:ProdottoDellaRicerca , prodotto:TIPO1101 . @prefix rdfs: . prodotto:ID5616 rdfs:label "Why hot horizontal branch stars can appear redder than red giants (Articolo in rivista)"@en . @prefix xsd: . prodotto:ID5616 pubblicazioni:anno "2003-01-01T00:00:00+01:00"^^xsd:gYear . @prefix skos: . prodotto:ID5616 skos:altLabel "
Momany Y., Cassisi S., Piotto G., Bedin L.R., Ortolani S., Lanfre' Castelli F., Recio-Blanco A. (2003)
Why hot horizontal branch stars can appear redder than red giants
"^^rdf:HTML ; pubblicazioni:autori "Momany Y., Cassisi S., Piotto G., Bedin L.R., Ortolani S., Lanfre' Castelli F., Recio-Blanco A."^^xsd:string ; pubblicazioni:paginaInizio "303"^^xsd:string ; pubblicazioni:paginaFine "309"^^xsd:string ; pubblicazioni:numeroVolume "407"^^xsd:string ; skos:note "ISI Web of Science (WOS)"^^xsd:string ; pubblicazioni:titolo "Why hot horizontal branch stars can appear redder than red giants"^^xsd:string . @prefix prodottidellaricerca: . prodotto:ID5616 prodottidellaricerca:abstract "In this paper we report on a curious feature in the V,(U-B) color-magnitude diagrams of globular clusters. In our database, we find that a considerable fraction of blue horizontal branch stars, hotter than the instability strip and cooler than the Grundahl et al. (1999) jump (i.e., 6000<~Teff(K)<~10000), have (U-B) colors redder than their red giants progenitors. This red incursion is not expected on theoretical grounds, as horizontal branch stars (whose convective regions are less extended than in red giant structures) should not ``appear'' cooler than a red giant.Analyzing data from different telescopes we show that: 1) the horizontal branch red incursion is strongly dependent on the shape of the adopted U filter and to a lesser extent, on the B filter; 2)the photometry done with U filters that do not encompass the Balmer jump shows the blue horizontal branch red incursion; 3) the occurence of this feature is also due to the peculiar dependence of the U and B magnitudes on star effective temperature, gravity, and metallicity; 4) theoretical tracks can reproduce the observed horizontal branch morphology, provided that the appropriate (i.e. exactly responding to the filters effectively used in the observations) transmission curve efficiencies are used for deriving color-Teff transformations; 5) the red incursion extent depends on metallicity." . @prefix istituto: . prodotto:ID5616 prodottidellaricerca:prodottoDi istituto:CDS005 ; pubblicazioni:autoreCNR unitaDiPersonaleInterno:MATRICOLA12320 . istituto:CDS005 prodottidellaricerca:prodotto prodotto:ID5616 .