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Some preliminary conclusions

Some preliminary conclusions. i) This mini-workshop: intended as an inter-CRP Eurogenesis meeting ii ) Putting it immediately after Acona helped in having colleagues from USA, while paying only once the intercontinental flights .

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Some preliminary conclusions

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  1. Some preliminaryconclusions i) This mini-workshop: intendedasaninter-CRPEurogenesis meeting ii) PuttingitimmediatelyafterAconahelped in havingcolleaguesfrom USA, whilepayingonly once the intercontinentalflights. iii) On the other side itmadedifficultforseveralEuropeansto come. HencewehadonlyfewrepresentativesfromotherCRPs (Decressin: First Stars; Chieffi: MASCHE; Longland: ExNuc). Thankstothemforcoming and contributing! iv) As a consequence, some (excessive?) emphasisturned out tobegivento the specificactivitiesof IP5 in CoDustMas (nuclearastrophysics). v) Thanksto the speciallyinvitedexternalcontributors (Andy, Inma, Carlos, Maria, Franz, Ernst) formaking the program more complete. vi) Levy Strauss usedtosaythat “Scientists are notonlythosewhogive the answers, butalsothosewhoask the questions”. vi) Profitingofthis, I’llonly pose some questions, emerged in this meeting (in some casesalso in Ascona), counting on mycolleages at thistable and in the roomtoprovideanswers….

  2. IMSs C-stars are of low mass (Cristallo). Previoushintsthattheyreach up to 4-5 M8 (Barnbaum & Zuckerman) notconfirmedrecently. AlsoO-richstars are notseen at high mass (Guanbdalini & Busso in preparation). Maybeselectioneffects, simply….. BUT: AGB nucleosynthesis, once attributedto IMS, nowrecongnizedtobefromlowermasses (Davis, Kaeppeler, Zinner, Maiorca, Palmerini,….). NOT ONE SINGLE PRESOLAR GRAIN OBSERVED FROM IMSs. Wherehaveallthe IMSsgone????? “Possible” needfor IMS dustcontributionsin earlyepochs(Dwek). Do they live shortly, e.g. onlythrough RGB or early-AGBphases, producingdustveryearly, and notgoingto the TP-AGB phases?

  3. Betternuclearphysicsinputs? i) Manyproblems in presolar dustabundances, previouslyattributedentirelyto mixing, mayberelatedalsotoinsufficientknowledgeofreactionrates (Imbriani, Palmerini). ii) Betternuclearinputsnecessaryalsoforveryheavyelements, alsofordustgrains(Kaeppeler, Davis). Howmuchofthis can beimprovedbybetterundergoundfacilities or measurementtechniques (Trezzi, Gialanella, Milazzo)? Howmuchofit can insteadby due topoortheoreticalapproachestogeneralproblems, like electron screening (semi-classicalDebye-Hueckel treatment, butit’s from the 30’s! Isitnot the timetohave a reallquantisticapprocahtoa Fermi electron gas? Where can wefindnuclearphysicstheoristswhishingtoundertakethis big task? Howmuch a bettermodelingofelectron screening (i.e. density: Busso et al,NIC XII,PoS) can affectweakinteractions?

  4. Basic Stellar EvolutionIssues Perculiarisotopiccompositions, notexplainedbynormal, single star evolution & nucleosynthesis, earlyobserved in SiCgrains (e.g. A+B: Zinner). Some ofthemunexplainedeven in explosivenucleosynthesisscenarios (novae, WD merging: Longland). Nowobservedalso in some starslooking, for the rest, like AGB Stars (e.g. CJ, SC….. Abia).  Isn’t ittimetoaffordfrom scratch the evolutionofclosebinarysystems?

  5. Young clustersrevealoverproductionof s elements Weshould do anyefforttohave more data, stimulating the observersto look notonly at GCc, butalso at OCs. In any case, tointerpretthemweneed GCE models, includingdust. Howgood are they? Do allofthemobtain the sameresults once given the sameinputs? Howlargeis the uncertainty in stellar lifetimes? Howmuch are theydependent on stillpoorlyknownreactionrates?

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