The University of Wroclaw (Poland) is pleased to announce the international summer school "Spectroscopic data analysis with iSpec". That will take place in Wroclaw, Poland between 26 and 29 June 2018.

The aim of this school is to give participants a thorough introduction into the treatment and analysis of stellar spectra, including deriving the atmospheric parameters and the chemical abundances. The tool which will be used for this purpose is the code iSpec.

iSpec is a tool for the treatment and analysis of stellar spectra. Some of the main functionalities for spectra treatment and library creation that are integrated into iSpec are the following: cosmic rays removal, continuum normalization, resolution degradation, radial velocity determination and correction, telluric lines identification, re-sampling. iSpec is also capable of determining atmospheric parameters (i.e effective temperature, surface gravity, metallicity, micro/macroturbulence, rotation) and individual chemical abundances for FGKM stars by using two different approaches: synthetic spectra fitting technique or equivalent widths method. iSpec integrates MARCS and ATLAS model atmospheres together with the following radial transfer codes: SPECTRUM (R. O. Gray), Turbospectrum (Bertrand Plez), SME (Valenti & Piskunov), MOOG (Chris Sneden), and Synthe/WIDTH9 (Kurucz/Atmos). The user-friendly interface is perfect for learning and testing. However, to take advantage of the full potential, iSpec can be used from Python. This is the recommended way to use iSpec for complex scientific studies, it ensures reproducibility and give access to a wider range of functionalities and options.

The participants of the school "Spectroscopic data analysis with iSpec" will be given introductory lectures to iSpec and some hands-on experience with determination of the atmospheric parameters of A, F, G, K, and M type stars. The exercises will be based on publicly available stellar spectra as well as on pre-computed synthetic spectra.

iSpec has been updated thanks to the contribution of several users:

  • Bug fix: Parameter determination not working properly from the visual interface
  • Bug fix: SME spectra was not correctly re-sampled before applying convolutions
  • MOOG now always computes molecular equilibrium for the most important species
  • Air <-> Vacuum conversion changed to follow IAU standard and VALD3

iSpec now supports several radiative transfer codes: SPECTRUM, Turbospectrum, SME, MOOG and SYNTHE/WIDTH9.

New version with only minor bug fixes such as:

  • Continuum fit was failing when the user has the latest version of the python dependencies.
  • The "Find line masks" option from the visual interface was not working.
  • The pre-processing stage of the iSpec pipeline failed when run in parallel.

Several important improvements were implemented in this new version:

  • iSpec now uses the SPECTRUM capabilities to compute synthetic spectra with hyperfine structure and isotopes
  • Alpha elements are automatically enhanced when the analysed stars are metal poor. It follows the standard mixture of the MARCS model atmosphere.
  • A complete automatic pipeline based on iSpec (synthetic spectral fitting technique) is released as an example (included in the virtual machine too).