This review covers the modern era of experimental kaonic atom studies, encompassing 20
years of activity, defined by breakthroughs in technological developments which allowed …

The new era in X-ray spectroscopy of exotic atoms is based on high-resolution reflection-
type crystal spectrometers, state-of-the-art X-ray detectors, and sophisticated set-ups to stop …

The possible existence of deeply bound nuclear K states is investigated theoretically for few-
body systems. The nuclear ground states of a K− in 3 He, 4 He, and 8 Be are predicted to be …

The kaonic helium-4 3d→ 2p X-ray transition was measured in a gaseous target, where
Compton scattering in helium is negligible. The X-rays were detected with large-area Silicon …

We have measured the Balmer-series x-rays of kaonic 4He atoms using novel large-area
silicon drift x-ray detectors in order to study the low-energy K¯-nucleus strong interaction …

The L-series X-rays transitions of the kaonic helium-4 exotic atom were measured by
SIDDHARTINO, the reduced configuration of the SIDDHARTA-2 experiment, at the DAΦNE …

The first observation of the kaonic 3He 3d→ 2p transition was made, using slow K− mesons
stopped in a gaseous 3He target. The kaonic atom X-rays were detected with large-area …

The X-ray spectrum obtained with kaons stopping in liquid hydrogen has been measured.
Possible candidates for X-ray lines from kaonic hydrogen atoms have been identified and …

The SIDDHARTA-2 experiment installed at the DA Φ NE collider of INFN-LNF performed, for
the first time, measurements of high-n transitions in intermediate mass kaonic atoms during …

We present the tests performed by the SIDDHARTA-2 collaboration at the DA Φ NE collider
with a quasi-hemispherical CdZnTe detector. The very good room-temperature energy …