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Spectral Line Access

This overview presents the essential spectroscopic databases available for astrophysical applications, highlighting theoretical and experimental line lists crucial for spectral analysis. It discusses various databases, including atomic databases like NIST and molecular databases such as HITRAN and JPL, providing insights into their structure and accessibility. Additionally, the document emphasizes the need for standardized access protocols to facilitate efficient retrieval of spectral information, thereby enhancing the ability to model and interpret astrophysical phenomena.

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Spectral Line Access

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  1. Paris Observatory and ESA/ESAC ML Dubernet, P. Osuna, M. Guanazzi, J. Salgado, E. Roueff MLD acknowledges support from VO-France, MDA project (F. Genova), Paris Observatory Spectral Line Access

  2. Project Overview (1) Access Atomic/Molecular DB startingwith line lists Theoretical (measured or calculated) DB Observed line lists DB Necessary to access complementary information in order to interpret spectra or model astrophysical media: excitation rate coefficients, etc.. Clients: stronger evolution towards public software packages for spectral analysis and on line codes for astro. Simulation Shared, structured, complete and documented access to AM DB Standardisation O/I, queries, ressources ID

  3. Overview (2) • Numerous DB are available • Atomic lines: NIST DBs, Kurucz's CD-ROM, Atomic Line List of P. Van Hoof, TOPbase, Kelly Atomic Line DB, VALD, MCHF/MCDHF Collection, D.R.E.A.M, KAERI AMODS • Molecular Lines: JPL Spectroscopic DB, CDMS, HITRAN, GEISA, NIST • Other DB: IEAE, NIFS, CHIANTI, UMIST, BASECOL, small compilations • Observed databases: ATOMDB, NIST, ... • Identification of Pbs • Different DB have similar datasets • DB have different levels of update • Lengthy to identify origin of datasets, find all relevant description of data • Useful data for a single astrophysical application are dispersed in various DB • No homogeneous description of data

  4. Access to Lines: Data Model Based on fundamental physics, current databases and needs in astrophysics Current DM is centered around line for atom and molecules: electronic, vibrational, rotational transitions (couplings) Allows for identification of Chemical Species Level -->Quantum State-->Quantum numbers Origin and modification of Line Can be used to model other processes involving transitions because a line corresponds to a transition between two levels Could be extended to nuclear physics

  5. H(3p2P03/2)---> H(1s 2S1/2) + hv

  6. Quantum Number: coupling N2H+ : rotationN, 3 nuclearSpinI level characterized with a single state |NF1F2F> N+I1= F1; F1+I2=F2; F2+I3 = F QuantumNumber : I1 name = nuclearSpinI type = nuclear spin of outer nitrogen origin = pure intValue = 1 QuantumNumber : F2 name = intermediateAngularMomentumF type = intermediate angular momentum origin = N + nuclearspinI (nuclear spin of outer nitrogen) + nuclearspinI (nuclear spin of inner nitrogen) value = 0

  7. DM : general transition model Each time a species undergoes a transition, it can be modeled by a Line DM A transition is modeled by Before .... Oups Something happens! ... After Light – Matter Interaction : bound-bound A(j) + hv ---> A(j') A(j') ---> A(j) + hv

  8. DM : general transition modelLight-Matter : bound-continuum Radiative recombinaison (Z, N-1)[level.of.Z(N-1)] + e ---> (Z, N)[level.of.Z(N)] + hv InitialElement = ChemicalElement IonizationStage = -1 (comparatively to N) Z is specified full atomic symbol is specified (see DM) FinalElement = ChemicalElement IonizationStage = 0 (comparatively to N) Z is specified full atomic symbol is specified (see DM)

  9. Excitation : A(i) + B(k) --> A(j) + B(l) TargetLine = Line : A initialElement=finalElement InitialLevel = i ; finalLevel = j PerturberLine = Line : B Other attributes specific to excitation Temperature Rate coefficients Reaction : AB(i) + C(k) --> A(j) +BC(l) Reactant = (1 to *) Line: AB, C InitialChemical: AB or C InitialLevel_species : i FinalLevel_species : none FinalChemical: none Products = (1 to *) Line: A, BC Reverse identification DM : general transition modelMatter – Matter Interaction

  10. DM document: Current status • Draft currently being written up • All attributes are carefully described following exact theoretical definitions • Most quantum numbers are described • In particular, most of the well known coupling cases

  11. DM : missing Provenance Observations : see characterization Measured Data : instrument and parameters Calculated sets : VOTheory Various steps in getting final data, ex : Method Hamiltonian (parameters, approximations), basis sets Algorithms Fitting functions: parameters, function, error Etc...

  12. Access : Query Parameters • Opened question for Line Access : SLAP : Simple Line Access Protocol • By wavelength_min, _max, _mid • By species: Fe I, H20, ... • By type of transition (E1, M1, E2) • By type of levels (vibration, rotation, ..) • Combined with associated processes • Would we allow search of other processes independently of lines ?

  13. Access to Lines: SLAP What information do we retrieve from a service implementing SLAP? Wavelength : mandatory Initial/Final ChemicalElement : should Name or atomicSymbol/formula : should Initial/Final Level : should QuantumState : should energy, statWeight : should Einstein A : should Optional : everything else

  14. Access to Lines: questions • Registry parameters? • Wavelength range • Keywords = energies, atoms or molecules, processes • Practically how should we proceed ? • Some DB will implement VO, otherwise create VO providers • Create Web Services and vizualization tools with filters

  15. Milestones : 2005-2006 • 1rst Draft « Atomic and Molecular Lines Data Model » : July 2005 • Agree on SLAP : July 2005 • Get inputs from community : until Sept. 05 • Implement simple prototype : Next Interop. • Extend DM: Provenance, .. Queries : 2006

  16. KAERI: Y.-J. Rhee ATOMDB: N. Brickhouse D. Schwenke J. Tennyson A bunch of french spectroscopists J. Aboudarham (solar) B. Plez (stars) J. Cernicharo (ISM) F. Valdes (calibration package) Contacted peoplePhysicists, Databases, Astronomers • GEISA: N. Husson-Jacquinet • HITRAN: L. Rothman • CDMS: S. Schlemmer • JPL: J. Pearson • UMIST: T. Millar • CHIANTI: P. Young • DREAM: P. Quinet • TOPBase: C. Zeippen • NIST: F. Lovas, Y. Ralchenko • NIFS: T. Kato • IEAE: B. Clark

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