Pushing the limit of instrument capabilities

Chemically Peculiar (CP) stars have been subject of systematic research since more than 50 years. With the discovery of pulsation of some of the cool CP stars, the availability of advanced spectropolarimetric instrumentation and high signal- to-noise, high resolution spectroscopy, a new era of CP star research emerged about 20 years ago. Together with the success in ground-based observations, new space projects are developed that will greatly benefit for future investigations of these unique objects. In this contribution we will give an overview of some interesting results obtained recently from ground-based observations and discuss on future outstanding Gaia space mission and its impact on CP star research.

[1]  Horace W. Babcock,et al.  A Catalog of Magnetic Stars. , 1958 .

[2]  Nikolai Piskunov,et al.  Abundance stratification and pulsation in the atmosphere of the roAp star $\boldmath\gamma$ Equulei , 2002 .

[3]  N. A. Sokolov,et al.  Radial velocity study of the chemically peculiar star ε Ursae Majoris , 2008, 0904.3562.

[4]  D. Kurtz.  12.15 Minute Light Variations in Przybylski's Star, HD 101065 , 1978 .

[5]  O. Kochukhov,et al.  The Paschen-Back effect in the Li I 6708 Å line and the presence of lithium in cool magnetic Ap stars , 2008, 0802.2631.

[6]  O. Kochukhov,et al.  Chemical stratification in the atmosphere of Ap star HD 133792. Regularized solution of the vertical inversion problem , 2006, astro-ph/0609312.

[7]  Nikolai Piskunov,et al.  Multi-element abundance Doppler imaging of the rapidly oscillating Ap star HR 3831 , 2004 .

[8]  George W. Preston,et al.  The chemically peculiar stars of the upper main sequence. , 1974 .

[9]  V. V. Stepanov,et al.  Doppler-Zeeman mapping of the magnetic CP star HD 215441 , 1997 .

[10]  F. Leone,et al.  Abundances and chemical stratification analysis in the atmosphere of Cr-type Ap star HD 204411 , 2005 .

[11]  W. J. Tango,et al.  The fundamental parameters of the roAp star α Circini , 2008, 0803.1518.

[12]  S. Hubrig,et al.  Stratification and isotope separation in CP stars , 2009, 0903.0611.

[13]  David Mary,et al.  A statistical analysis of the detection limits of fast photometry , 2006 .

[14]  O. Kochukhov,et al.  Rare-earth elements in the atmosphere of the magnetic chemically peculiar star HD 144897 , New classification of the Nd III spectrum , 2006, astro-ph/0604546.

[15]  O. Kochukhov,et al.  Stellar model atmospheres with magnetic line blanketing , 2007 .

[16]  M. Jasiński,et al.  Variation of radial velocity of the Ap star epsilon UMa. , 1980 .

[17]  N. Przybilla,et al.  HVS 7 - a chemically peculiar hyper-velocity star ⋆ , 2008, 0810.0864.

[18]  Petr Škoda,et al.  The extremely rapid rotational braking of the magnetic helium-strong star HD 37776 , 2008 .

[19]  D. Shulyak,et al.  Stellar model atmospheres with magnetic line blanketing II. Introduction of polarized radiative transfer , 2005, astro-ph/0511744.

[20]  Astronomy Department,et al.  Model atmospheres of magnetic chemically peculiar stars - A remarkable strong-field Bp SiCrFe star HD 137509 , 2008, 0806.1296.

[21]  Andrew Collier Cameron,et al.  Spectropolarimetric observations of active stars , 1997 .

[22]  Werner W. Weiss,et al.  Line-by-line opacity stellar model atmospheres , 2004 .

[23]  Achim Feldmeier,et al.  Clumping in hot-star winds , 2008 .

[24]  B.-C. Lee,et al.  The Lorentz force in atmospheres of CP stars: θ Aurigae , 2007 .

[25]  Uppsala University,et al.  Model atmospheres of chemically peculiar stars: Self-consistent empirical stratified model of HD24712 , 2009, 0903.3474.

[26]  O. Kochukhov,et al.  Isotopic anomaly and stratification of Ca in magnetic Ap stars , 2008, 0801.2245.

[27]  Carl J. Grillmair,et al.  STELLAR PULSATION: CHALLENGES FOR THEORY AND OBSERVATION , 2009 .

[28]  G. Michaud,et al.  Diffusion Processes in Peculiar a Stars , 1970 .

[29]  Gregg A. Wade,et al.  Spectropolarimetric measurements of magnetic Ap and Bp stars in all four Stokes parameters , 2000 .

[30]  D. V. Shulyak,et al.  Stellar model atmospheres with magnetic line blanketing III. The role of magnetic field inclination , 2006 .

[31]  G. Mathys,et al.  A 3D study of the photosphere of HD 99563 – I. Pulsation analysis , 2009, 0904.3530.

[32]  N. Nesvacil,et al.  The spectroscopic signature of roAp stars , 2004 .

[33]  N. Mowlavi,et al.  Detecting Short Period Variable Stars with Gaia , 2009 .

[34]  O. Kochukhov,et al.  A self-consistent empirical model atmosphere, abundance and stratification analysis of the benchmark roAp star $\alpha$ Circini , 2009, 0903.3512.

[35]  O. Kochukhov.  Pulsational line profile variation of the roAp star HR 3831 , 2005 .