Nuclei with Z=1....54 / Landolt-Börnstein, Numerical Data and Functional Relationships in Science and Technology Vol.22a
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Introduction Generalremarks Thisreportisthecompilationofexperimentalandtheoreticaldataonatomicmasses,nuclear bindingenergies,nucleonseparationenergies,Q-valuesofsomenuclearreactionsandpar- etersof nucleonresidualinteractionsderivedfromdifferencesof nuclearbindingenergies.It consistsoftwoparts,volumesI/22AandI/22B,inwhichdatafornucleiwithatomicnumbers Z = 1?54andZ ? 55arepresented.EarlierQ-valuesofnuclearreactionswereconsideredin volume1/5AoftheNewSeriesLandoldt-Börnsteinlibrary[73Sc0A].Thedatainourcompi- tionarepresentedintableswhoseformatisanalogoustothatofothercompilationsofatomic masses (A...
Introduction Generalremarks Thisreportisthecompilationofexperimentalandtheoreticaldataonatomicmasses,nuclear bindingenergies,nucleonseparationenergies,Q-valuesofsomenuclearreactionsandpar- etersof nucleonresidualinteractionsderivedfromdifferencesof nuclearbindingenergies.It consistsoftwoparts,volumesI/22AandI/22B,inwhichdatafornucleiwithatomicnumbers Z = 1?54andZ ? 55arepresented.EarlierQ-valuesofnuclearreactionswereconsideredin volume1/5AoftheNewSeriesLandoldt-Börnsteinlibrary[73Sc0A].Thedatainourcompi- tionarepresentedintableswhoseformatisanalogoustothatofothercompilationsofatomic masses (AM), nuclear binding energies (E ), atomic mass excesses of nuclei (ME,ME = 0 B 12 for Cbyde?nition),Q-valuesandseparationenergiesofasinglenucleonorapairofnuc- ons(S ,S ,S ,S )[05Au0A,05Wa35,03Au03,03AuZZ,03Wa32,02Wa27,01Au10,95Au04, n p 2n 2p 85Wa02,85Bo10,37Li0A]. AtomicmassesM areconnectedwithnuclearmassesM bytheformula: A N M (A,Z) =M (A,Z)+Z ×m ?B (Z) (1) A N e el ?4 wherem = 510.99892(4)keV = 5.485799094(2)×10 uistheelectronrestmass(inatomic e massunitu)[06Ya08].ThetotalbindingenergyofallremovedelectronsB (Z)canbefound el in [76Hu0A] or approximated with the expression given by Lunney, Pearson and Thibault [03Lu10]: 2.39 ?6 5.35 B (Z) = (14.4381×Z +1.55468×10 Z )eV (2) el The mass excess,M (A,Z) ?Au, and the nuclear binding energy E calculated by the A B formula: E =Z ×M(p)+N ×M(n)?M (A,Z) (3) B N areusuallygiveninunitkeV.HerevaluesM(p)andM(n)arethemassesofthenucleons.There isanassumptionthattheuncertaintyincalculatedvalueB (about150eVfortheatomswith el Z 100 [03Lu10]) is smaller than the experimental error. If ionized atoms are involved in massmeasurementsthiscorrectionisappliedforthedeterminationoftheatomicmass. Themassexcessisrepresentedusuallysimultaneouslywiththetotalnuclearbindingenergy (E )orthebindingenergypernucleonE /A.Thelattervalueisconnectedwiththestabilityof B B nucleiandshowsamaximumaroundthe iron-peak importantinastrophysics[03Au03].As inothermasscompilationswegivenucleonandtwo-nucleonseparationenergies.Clustering effectsinnucleardataarepresentedbyseparationenergiesofdifferentnucleoncombinations (S ,S ,etc.).Forneutronseparationenergiesonlythemostprecisevaluesfromtherecent 2p2n 2p4n neutroncaptureexperimentsarepresented.Inseveralcasesonlynucleonseparationenergies areknownaccuratelywhiletotalbindingenergiesremainuncertain(insuchcasesweinclude newseparationenergy). The experimental study of atomic masses started nearly hundred years ago. In the p- neeringworkofAston[27As0A]nuclearbindingenergieswereobtainedformanynucleiand Landolt-Börnstein DOI:10.1007/978-3-540-69945-3_1 NewSeriesI/22A ©Springer2009 21 Introduction nearconstancyof theaveragebindingenergypernucleonsuggestedtheindependenceof the nucleardensitywiththeatomicweightAandthesaturationof thenuclearforces.Thesetwo nuclear features were represented by the ?rst mass formula byWeizsäcker in 1935 [35Vo0A] inspired by the liquid-drop model (DM) of the nucleus by Nils Bohr. The Bethe-Weizsäcker formula is extended recently in [08Me01, 08Ki01]. Some methodical aspects of earlier mass measurementswerediscussedbyWapstraandAudi[01Wa49,06Au0A].