KAONIC ATOMS AT DAΦNE — THE SIDDHARTA EXPERIMENT

2009 ◽  
Vol 24 (02n03) ◽  
pp. 190-197 ◽  
Author(s):  
◽  
J. ZMESKAL ◽  
M. BAZZI ◽  
G. BEER ◽  
L. BOMBELLI ◽  
...  
Keyword(s):  
Chiral Symmetry Breaking ◽  
Wave Interaction ◽  
Substantial Improvement ◽  
Kaonic Hydrogen ◽  
Silicon Drift Detector ◽  
S Wave ◽  
Hydrogen Atoms ◽  
X Ray ◽  
Electron Positron ◽  
Hadronic Atom

With precision X-ray spectroscopy of kaonic hydrogen at the DAΦNE electron-positron collider at Laboratori Nazionali di Frascati the chiral symmetry breaking scenario in the strangeness sector will be investigated by studying the K-p s-wave interaction at threshold. This is possible by observing the strong interaction induced shift and width of the 1s state in kaonic hydrogen atoms. The results of the first measurement at LNF with DEAR (DAΦNE Exotic Atom Research) will be given and the new SIDDHARTA (Silicon Drift Detector for Hadronic Atom Research with Timing Application) project will be described, which is aiming at a substantial improvement of the preceding DEAR result.

scholarly journals X-ray Detectors for Kaonic Atoms Research at DAΦNE

2019 ◽  
Vol 4 (2) ◽  
pp. 42 ◽  
Author(s):  
Catalina Curceanu ◽  
Aidin Amirkhani ◽  
Ata Baniahmad ◽  
Massimiliano Bazzi ◽  
Giovanni Bellotti ◽  
...  
Keyword(s):  
National Laboratory ◽  
Kaonic Hydrogen ◽  
Silicon Drift Detector ◽  
Kaonic Atom ◽  
X Ray ◽  
Kaonic Atoms ◽  
Technological Advances ◽  
Kaonic Deuterium ◽  
First Time ◽  
Hadronic Atom

This article presents the kaonic atom studies performed at the INFN National Laboratory of Frascati (Laboratori Nazionali di Frascati dell’INFN, LNF-INFN) since the opening of this field of research at the DA Φ NE collider in early 2000. Significant achievements have been obtained by the DA Φ NE Exotic Atom Research (DEAR) and Silicon Drift Detector for Hadronic Atom Research by Timing Applications (SIDDHARTA) experiments on kaonic hydrogen, which have required the development of novel X-ray detectors. The 2019 installation of the new SIDDHARTA-2 experiment to measure kaonic deuterium for the first time has been made possible by further technological advances in X-ray detection.

scholarly journals AMADEUS Experiment: Studies on Antikaon Interactions with Nucleons and Nuclei

2018 ◽  
Vol 46 ◽  
pp. 1860071
Author(s):  
J. Marton ◽  
K. Piscicchia
Keyword(s):  
Bound States ◽  
Experimental Studies ◽  
Drift Chamber ◽  
Kaonic Hydrogen ◽  
Nucleon Interaction ◽  
S Wave ◽  
Data Set ◽  
Electron Positron ◽  
Low Energies ◽  
Kloe Collaboration

The understanding of the low-energy strong interaction involving strangeness is a challenging topic due to resonances and predicted kaonic nuclear bound states. The K- nucleon interaction is strongly attractive at low energies verified in kaonic hydrogen studied in the SIDDHARTA experiment at the DA[Formula: see text]NE electron-positron collider of LNF-INFN (Frascati/Italy). Hyperon resonances like the elusive [Formula: see text] in the s-wave impose questions about its nature. According to theoretical studies it can be described as a dynamically generated resonance with two poles or a quasi-bound [Formula: see text]N state, which could lead to kaonic nuclear bound states (e.g. K-pp). An insight in many open facets of the antikaon interactions can be provided by the AMADEUS experiment at DA[Formula: see text]NE based on the analysis of the data collected in 2004/2005 by the KLOE collaboration, and of the dedicated data set collected in 2012 by AMADEUS in collaboration with KLOE. As a first step data from antikaon-induced reactions in the drift chamber of KLOE were analyzed and yielded new results on antikaon absorption on nuclei. Recent results of the experimental studies and an outlook to the future possibilities within AMADEUS are presented.

Kaonic hydrogen X-rays — experiments at DAFNE

2007 ◽  
Vol 85 (5) ◽  
pp. 479-485 ◽  
Author(s):  
M Cargnelli ◽  
T Ishiwatari ◽  
P Kienle ◽  
J Marton ◽  
E Widmann ◽  
...  
Keyword(s):  
Chiral Symmetry Breaking ◽  
Low Energy ◽  
Kaonic Hydrogen ◽  
X Rays ◽  
Large Area ◽  
X Ray ◽  
Kaonic Deuterium ◽  
Research Experiment ◽  
Scattering Lengths ◽  
Excellent Energy Resolution

At the DAΦNE electron–positron collider of Laboratori Nazionali di Frascati we study kaonic atoms, taking advantage of the low-energy kaons produced in the Φ-meson decay. The low-energy kaon–nucleon interaction in kaonic hydrogen and kaonic deuterium can be investigated under favorable conditions. The DEAR (DAΦNE Exotic Atom Research) experiment at LNF delivered the most precise data on kaonic hydrogen up to now. DEAR and its follow-up experiment SIDDHARTA (Silicon Drift Detector for Hadronic Atom Research by Timing Application) are using X-ray spectroscopy of kaonic hydrogen and kaonic deuterium atoms to measure the strong interaction-induced shift and width of the ground state. From these quantities the isospin-dependent antikaon–nucleon scattering lengths can be determined, quantities useful for testing the understanding of chiral symmetry breaking in the strangeness sector. Within the SIDDHARTA project new X-ray detectors are being developed. We will use an array of large area silicon drift detectors (SDDs) having excellent energy resolution but also providing a timing capability that will result in a huge suppression of background and so overcome the precision limits of the former experiments.PACS Nos.: 36.10.k, 13.75.Jz, 32.30.Rj and 29.40.Wk

KAONIC HELIUM MEASUREMENTS IN THE SIDDHARTA EXPERIMENT

2011 ◽  
Vol 26 (03n04) ◽  
pp. 601-603
Author(s):  
◽  
D. L. SIRGHI ◽  
M. BAZZI ◽  
G. BEER ◽  
L. BOMBELLI ◽  
...  
Keyword(s):  
Energy Shift ◽  
High Energy ◽  
Low Energy ◽  
Kaonic Hydrogen ◽  
X Rays ◽  
X Ray ◽  
Kaonic Deuterium ◽  
Theoretical Predictions ◽  
First Time ◽  
Hadronic Atom

The SIDDHARTA experiment (SIlicon Drift Detector for Hadronic Atom Research by Timing Application) had the aim to perform kaonic atoms X-ray transitions measurements, to better understand aspects of the low-energy QCD in the strangeness sector. The experiment combined the excellent low-energy kaon beam generated at DAΦNE, allowing to use gaseous targets, with excellent fast X-rays detectors: Silicon Drift Detectors. SIDDHARTA was installed on DAΦNE in autumn 2008 and took data till late 2009. Apart of the kaonic hydrogen and kaonic deuterium measurements, we have performed the kaonic helium transitions to the 2p level ( L -lines) measurements: for the first time in a gaseous target for helium4 and for the first time ever for kaonic helium3. The interest for such type of measurement was rather high, being it triggered by two reasons: the so-called "kaonic helium puzzle" (even if this was solved by KEK-PS E570 experiment, but a cross-check was useful) and some theoretical predictions of possible high energy shift (at the level of 10 eV). In this paper the preliminary results for the measurements to the 2p level ( L -series) for kaonic helium4 and kaonic helium3 are presented.

scholarly journals K -series X-ray yield measurement of kaonic hydrogen atoms in a gaseous target

2016 ◽  
Vol 954 ◽  
pp. 7-16 ◽  
Author(s):  
M. Bazzi ◽  
G. Beer ◽  
G. Bellotti ◽  
C. Berucci ◽  
A.M. Bragadireanu ◽  
...  
Keyword(s):  
Kaonic Hydrogen ◽  
Hydrogen Atoms ◽  
X Ray ◽  
Yield Measurement ◽  
Gaseous Target

scholarly journals Resonant Effect of High-Energy Electron–Positron Pairs Production in Collision of Ultrarelativistic Electrons with an X-ray Electromagnetic Wave

Universe ◽  
2021 ◽  
Vol 7 (7) ◽  
pp. 210
Author(s):  
Georgii K. Sizykh ◽  
Sergei P. Roshchupkin ◽  
Victor V. Dubov
Keyword(s):  
High Energy ◽  
Energy Electron ◽  
Opening Angle ◽  
High Energy Electron ◽  
Scattered Electron ◽  
Differential Probability ◽  
X Ray ◽  
Electron Positron ◽  
Pulsar Radiation ◽  
Resonant Effect

The process of resonant high-energy electron–positron pairs production by electrons in an X-ray pulsar electromagnetic field is studied theoretically. Under the resonance conditions, the second-order process under consideration effectively reduces into two sequential first-order processes: X-ray-stimulated Compton effect and X-ray–stimulated Breit–Wheeler process. The kinematics of the process is studied in detail: the dependencies of the energy of the scattered electron on its outgoing angle and the energies of the particles of the pair on the outgoing angle of the scattered electron and the opening angle of the pair are obtained. The analysis of the number of different possible particles energies values in the entire range of the angles is also carried out, according to which the energies of the particles of the pair can take up to eight different values at a fixed outgoing angle of the scattered electron and opening angle of the pair. The estimate of the resonant differential probability per unit time of the process, which reaches the maximum value of 24 orders of the value of the non-resonant differential probability per unit time, is obtained. The angular distribution of the differential probability per unit time of the process is analyzed, particularly for the case of high-energy positrons presenting in pulsar radiation.

The first proof of protonated anion tetrahedra in the tsumcorite-type compounds

2004 ◽  
Vol 68 (5) ◽  
pp. 757-767 ◽  
Author(s):  
T. Mihajlović ◽  
H. Effenberger
Keyword(s):  
Crystal Structure ◽  
Hydrothermal Synthesis ◽  
Single Crystal ◽  
Diffraction Data ◽  
Title Compound ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Hydrogen Atoms ◽  
Synthetic Compounds ◽  
X Ray

AbstractHydrothermal synthesis produced the new compound SrCo2(AsO4)(AsO3OH)(OH)(H2O). The compound belongs to the tsumcorite group (natural and synthetic compounds with the general formula M(1)M(2)2(XO4)2(H2O,OH)2; M(1)1+,2+,3+ = Na, K, Rb, Ag, NH4, Ca, Pb, Bi, Tl; M(2)2+,3+ = Al, Mn3+, Fe3+, Co, Ni, Cu, Zn; and X5+,6+ = P, As, V, S, Se, Mo). It represents (1) the first Sr member, (2) the until now unknown [7]-coordination for the M(1) position, (3) the first proof of (partially) protonated arsenate groups in this group of compounds, and (4) a new structure variant.The crystal structure of the title compound was determined using single-crystal X-ray diffraction data. The compound is monoclinic, space group P21/a, with a = 9.139(2), b = 12.829(3), c = 7.522(2) Å, β = 114.33(3)°, V = 803.6(3) Å3, Z = 4 [wR2 = 0.065 for 3530 unique reflections]. The hydrogen atoms were located experimentally.

scholarly journals Hydrogen atoms in protein structures: high-resolution X-ray diffraction structure of the DFPase

2013 ◽  
Vol 6 (1) ◽  
pp. 308 ◽  
Author(s):  
Mikael Elias ◽  
Dorothee Liebschner ◽  
Jurgen Koepke ◽  
Claude Lecomte ◽  
Benoit Guillot ◽  
...  
Keyword(s):  
High Resolution ◽  
Protein Structures ◽  
X Ray Diffraction ◽  
Hydrogen Atoms ◽  
X Ray ◽  
Diffraction Structure

Bestimmung von innermolekularen Torsionswinkeln aus Hyperfeinstruktur-Aufspaltungen und g-Faktoren

1965 ◽  
Vol 20 (9) ◽  
pp. 1117-1121 ◽  
Author(s):  
K. Möbius
Keyword(s):  
Electron Diffraction ◽  
Aromatic Hydrocarbon ◽  
Aromatic Hydrocarbons ◽  
Small Amplitude ◽  
Membered Ring ◽  
Radical Ions ◽  
Hydrogen Atoms ◽  
Stereochemical Structure ◽  
X Ray ◽  
Phenyl Rings

The stereochemical structure of aromatic hydrocarbons in solution being overcrowded with hydrogen atoms is not known with certainty, because the conventional X-ray and electron diffraction methods are suitable only for samples in the crystalline and vapor phase. Using EPR spectroscopy for the aromatic hydrocarbon radicals biphenyl (—), phenanthrene (—) and pentaphenylcyclopentadienyl (PPCPD) innermolecular twist and bond angles could be determined by means of hfssplittings and g-factors. Stably solvated biphenyl radical ions are found to have twist angles of 38 ±2°; phenanthrene ions turn out to be planar but change their angles of hybridization at particular positions; in the PPCPD radical the phenyl rings oscillate with small amplitude around planes orthogonal to the five-membered ring.

Sign in / Sign up

Export Citation Format

Share Document