宇宙科学談話会

ISAS Space Science Colloquium & Space Science Seminar

ENGLISH

Laboratory astrophysics with electron beam ion traps

J. R. Crespo López-Urrutia
Max-Planck-Instutite fuer Kernphysik

At very high temperatures, atomic physics becomes the physics of highly charged ions (HCI). The presence of a few, still bound, electrons makes HCI from'metals'efficient absorbers and emitters of X rays, EUV, VUV and optical photons. Clear spectroscopic signatures from HCI are identifiably even at locations where the dominant light chemical elements are fully stripped, such as in AGN. Within the radiative zones of stars, HCI have a dominant contribution to the opacity. Future X-ray missions will provide unprecedented amounts of high-resolution spectral data. This will challenge our current atomic physics modelling of HCI, which is still limited by theoretical uncertainties and a lack of laboratory benchmarks for spectral models. Presently, existing laboratory data show clear disagreements with widely used astrophysical codes, call-ing for updating models. At the same time, the further development of atomic structure theory needed to generate data on collisional excitation and recombination, as well as photon-driven processes in astrophysical plasmas benefits from laboratory studies of HCI. Improving such benchmark measurements is an important task, ahead of the upcoming XRISM Resolve, Athena and Arcus missions. Electron beam ion traps (EBITs) are compact devices that produce, trap and excite HCI from N3+ (N IV) to U91+ (U XLII) under well-defined, steady-state conditions of charge state as well as excitation by a monoenergetic electron beam. They are sources for high-resolution spec-troscopy in all photon energy ranges. Dielectronic recombination, electron-impact excitation, and charge exchange are studied in detail using them.
Together with free-electron lasers and synchrotron radiation sources, EBITs have enabled soft X-ray laser spectroscopy, reaching by now up to the K-shell transitions of heavy elements.

4/9 14:00-17:00: Tutorial(1)
4/10 9:30-12:30: Tutorial(2)
4/10 14:00-16:00: Free discussion
(Room: Research and Administration Building , 6F, 1639)

 

実験室宇宙物理学の世界的拠点であるマックスプランク核物理学研究所において研究グループを率いるJose Crespo López-Urrutia氏より、電子ビームイオントラップ(EBIT)を用いたプラズマ実験の最先端を紹介いただきます。 また来所に合わせて2日間に渡るレクチャーを以下のスケジュールで行います。 ご都合のつく方はこちらも合わせてご参加ください。

4/9 14:00-17:00: Tutorial(1)
4/10 9:30-12:30: Tutorial(2)
4/10 14:00-16:00: Free discussion
(Room: Research and Administration Building , 6F, 1639)

Place: Shin-A 2F Conf. room A (1257) / 新A棟2階会議室A(1257号室)