@article{chung_2004, title={Resonances in atomic photoionization}, volume={70}, ISSN={["0969-806X"]}, DOI={10.1016/j.radphyschem.2003.12.006}, abstractNote={Resonances give rise to the most interesting features in atomic photoionization spectra. Over the past forty years, the study of these resonances has stimulated much excitement in theories as well as in experiments. The close agreement finally achieved between theory and experiment has verified the predictions of the theory which in turn lead to better understanding of the physical process and advances the knowledge on the physical system. In this work, we will discuss some of the advances made in this area for low-Z atomic systems with emphasis on the lithium atom as an example. In particular, we will discuss the calculation of resonance parameters using the saddle-point method and saddle-point complex method.}, number={1-3}, journal={RADIATION PHYSICS AND CHEMISTRY}, author={Chung, KT}, year={2004}, pages={83–94} }
 @article{bruch_merabet_chung_2003, title={Excitation of triply excited Be+ (2lnl ' n ' l '') states in 300 and 500 keV-Be++CH4 collisions}, volume={205}, ISSN={["0168-583X"]}, DOI={10.1016/S0168-583X(02)01937-7}, abstractNote={We have studied high resolution beryllium Auger electron spectra in the 120–160 eV projectile electron energy range following intermediate energies (1.2 and 1.5 a.u. impact velocities) in Be+ + CH4 ion–molecule single collisions [Comments At. Mol. Phys. D 14 (1984) 117]. The major focus of this study is the double K-shell excitation of the Be+ projectile forming triply excited BeII*** states (hollow atoms) and BeIII** K shell ionization plus excitation of BeII doubly excited states with two inner shell vacancies. In such intermediate velocity ion-molecular collisions, the CH4 target plays an important role in the enhancement of the population of BeII*** triply excited states when compared to a more tightly bound He (1s2) 1S ground state target. Due to the pioneering theoretical work of Gou and Chung [Phys. Rev. A 29 (1996) 6103] most line structures can now be unambiguously identified. The main triply excited states are associated with the 2s22p, 2s2p2 and 2p3 and 2l2l′n′l″ (n=3 and 4) configurations decaying to different final BeIII (1snl) ionic states. The line identification method used here is based on Auger energy levels, decay channels and branching ratios.}, journal={NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS}, author={Bruch, R and Merabet, H and Chung, KT}, year={2003}, month={May}, pages={488–493} }
 @article{lin_hsue_chung_2002, title={Auger width and branching ratios for berylliumlike 1s2s(2)np P-1(0) and 1s2p(3 1)P(0) resonances and photoionization of beryllium from 1s(2)2s2 S-1}, volume={65}, ISSN={["1094-1622"]}, DOI={10.1103/physreva.65.032706}, abstractNote={The photoionization cross section (PICS) of Be from the ground state is studied with the saddle-point complex-rotation method for photon energies from 25 to 122 eV. A full-core plus correlation wave function is used for the ground state. For the resonances in the continuum, the energy and width for the singly core-excited Be-like ${1s2s}^{2}2p{}^{1}{P}^{o},$ ${1s2p}^{3}{}^{1}{P}^{o},$ and ${1s2s}^{2}3p{}^{1}{P}^{o}$ are calculated to high precision. The PICS are studied with a single open-channel approximation as well as fully coupled open channels. The Auger decay branching ratios of these states are studied to check the spin-alignment theory recently proposed by Chung. These results are compared with the existing theoretical and experimental data in the literature. For beryllium, our energy and width of ${1s2s}^{2}2p$ are 115.513 eV and 36.6 meV and those of ${1s2s}^{2}3p$ are 121.420 eV and 50.4 meV, which agree with the experiment of Caldwell et al., [Phys. Rev. A 51, 542 (1990)].}, number={3}, journal={PHYSICAL REVIEW A}, author={Lin, H and Hsue, CS and Chung, KT}, year={2002}, month={Mar} }
 @article{chung_2001, title={3l3l ' 3l '' states of He- - art. no. 052503}, volume={6405}, DOI={10.1103/physreva.64.052503}, abstractNote={Extensive complex-rotation calculations are carried out for eight ${\mathrm{He}}^{\ensuremath{-}}$ ${3l3l}^{\ensuremath{'}}{3l}^{\ensuremath{''}}$ states in order to understand the resonance structure of ${\mathrm{He}}^{\ensuremath{-}}$ below the He ${3s3p}^{1}{P}^{o}$ threshold. It is found that the spectrum is very different from that of the ${\mathrm{He}}^{\ensuremath{-}}$ ${2l2l}^{\ensuremath{'}}{2l}^{\ensuremath{''}}$ states. A $3s\ensuremath{-}3p$ energy inversion is uncovered. Our result suggests that unlike the resonance structures below the $n=2$ region, ${3s3p}^{2}{}^{2}S$ and ${3s3p}^{2}{}^{2}P$ do form closed-channel resonances below the $3s3p{}^{3}{P}^{o}$ threshold. The results of this study are used to understand the scattering experiment of Roy [Phys. Rev. Lett. 38, 1062 (1977)].}, number={5}, journal={Physical Review. A}, author={Chung, K. T.}, year={2001}, pages={2503-} }
 @article{lin_hsue_chung_2001, title={Anger width and branching ratios for Be-like 1s2s(2)2p P-3(0) and 1s2s2p(2) S-3,P-3,D-3 resonances and photoionization of Be from 1s(2)2s2p P-3(0)}, volume={64}, ISSN={["1094-1622"]}, DOI={10.1103/physreva.64.012709}, abstractNote={The energy and Auger width for the singly core-excited Be-like ${1s2s}^{2}2p{}^{3}{P}^{o},$ ${(1s2s)}^{3}{S,2p}^{2}{}^{3}P,$ ${(1s2s)}^{1}{S,2p}^{2}{}^{3}P,$ and ${1s2s2p}^{2}{}^{3}{S}^{3}D$ states are calculated using a saddle-point complex-rotation method. The decay branching ratios of these states are calculated to check the spin-alignment-dependent Auger decay theory recently proposed by Chung. These branching ratios also enable us to make many positive identifications in the observed Auger spectra. In addition, the photoionization cross section (PICS) from the Be ${1s}^{2}2s2p{}^{3}{P}^{o}$ state is calculated for photon energies from 30 eV to 125 eV, including the resonance region. Accurate initial and final state wave functions are used. We find that although the Auger width of the ${(1s2s)}^{3}{S,2p}^{2}{}^{3}P$ transition is smaller than that of ${(1s2s)}^{1}{S,2p}^{2}{}^{3}P$ by a factor of 2.5, its peak PICS is larger by a factor of more than 300.}, number={1}, journal={PHYSICAL REVIEW A}, author={Lin, SH and Hsue, CS and Chung, KT}, year={2001}, month={Jul} }
 @article{chung_2001, title={Atomic system under synchrotron and laser radiation}, volume={684}, DOI={10.1016/s0375-9474(01)00401-8}, number={2001 Mar. 12}, journal={Nuclear Physics. A}, author={Chung, K. T.}, year={2001}, pages={256C–265} }
 @article{shiu_hsue_chung_2001, title={Auger branching ratios for berylliumlike 1s2s2p(2) S-1,P-1,D-1 resonances and photoionization of beryllium from 1s(2) 2s2p P-1(o)}, volume={64}, ISSN={["1094-1622"]}, DOI={10.1103/physreva.64.022714}, abstractNote={The photoionization cross section of Be from ${1s}^{2}{2s2p}^{1}{P}^{o}$ is studied with the saddle-point complex-rotation method for photon energies from 23 to 117 eV. A full-core plus correlation wave function is used for the initial states. In the continuum, the energy and width for the singly core-excited Be-like ${1s2s2p}^{2}{}^{1}S,{}^{1}P,$ and ${}^{1}D$ states are calculated to high precision for systems with $Z=4--10.$ The Auger decay branching ratios of these states are studied to check the spin alignment theory recently proposed by Chung. These results are compared with the available experimental data in the literature.}, number={2}, journal={PHYSICAL REVIEW A}, author={Shiu, VC and Hsue, CS and Chung, KT}, year={2001}, month={Aug} }
 @article{fang_chung_2001, title={Electric-field effects on He ground-state photoionization}, volume={34}, ISSN={["0953-4075"]}, DOI={10.1088/0953-4075/34/7/308}, abstractNote={A saddle-point complex-rotation method is used to study the photoionization of helium in the presence of a dc electric field. A four-angular-symmetry calculation (i.e. Lmax = 3) is carried out to study two locally isolated resonance groups, one consisting of He (2, 5c) 1Po, (2, 5b) 1Se, (2, 6b) 1Po and (2, 6a) 1Se states, and the other consisting of He (2, 6c) 1Po, (2, 6b) 1Se, (2, 7b) 1Po and (2, 7a) 1Se states. The variations of the structure of cross section profiles and resonance strengths for the ML = 0 components of these two resonance groups are examined in detail. A general Ntot-state sum rule for the total resonance strength Stot is shown, which suggests that the sum of the total resonance strength of a locally isolated resonance group is not affected by the presence of a weak static field. We have also performed a five-symmetry (i.e. Lmax = 4) multichannel calculation for the doubly excited spectra converging to the n = 3 threshold of He+. Overlapping resonances are found and resolved.}, number={7}, journal={JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS}, author={Fang, TK and Chung, KT}, year={2001}, month={Apr}, pages={1245–1259} }
 @article{fang_chung_2001, title={L-2 K-matrix method for triply excited lithium - art. no.020702}, volume={6302}, number={2}, journal={Physical Review. A}, author={Fang, T. K. and Chung, K. T.}, year={2001}, pages={702} }
 @article{chung_fang_2001, title={Photoionization of lithium 1s(2)2s and 1s(2)2p near the triply excited resonances}, volume={63}, ISSN={["1094-1622"]}, DOI={10.1103/physreva.63.062716}, abstractNote={A newly developed saddle-point multichannel K-matrix method is used to study the photoionization of lithium from ${1s}^{2}2s$ and ${1s}^{2}2p$ for photon energies near the $2p2p2p$ ${}^{2}{P}^{o}$ and $2s2p2p$ ${}^{2}{L}^{e}$ $(L=0,1,2)$ resonances. Highly accurate initial- and target-state wave functions are used and up to 17 open channels are included in the calculation. The calculated partial and total photoionization cross sections are compared with the available theoretical and experimental data. The partial cross sections obtained in this work suggests that for Li ${1s}^{2}2s$ and ${1s}^{2}2p$ initial states, the $1s$ electron with spin antiparallel to that of the $2s$ (or $2p)$ electron is the one most likely to be ejected in the photoionization process. The elastic and inelastic electron-ion scattering cross sections are also calculated. The relative magnitude of the calculated collision strength is compared with the Auger branching ratios for these resonances.}, number={6}, journal={PHYSICAL REVIEW A}, author={Chung, KT and Fang, TK}, year={2001}, month={Jun} }
 @article{chung_fang_ho_2001, title={Resonances of helium in a DC field}, volume={34}, ISSN={["0953-4075"]}, DOI={10.1088/0953-4075/34/2/304}, abstractNote={A saddle-point complex-rotation method is used to study electric-field effects on the doubly excited resonances of He. By using a 892-term wavefunction, a seven-angular-symmetry calculation (i.e. Lmax = 6) is performed for a comprehensive study around the He (2, 6a) 1Po and (2, 6a) 1De resonance pair in the presence of an external electric field. A general M-state sum rule is shown which suggests the sum of total energy or total width of M-state system is not affected by the presence of a weak static field. The M-state sum rule is used to investigate the sharing of resonance energies and widths for the locally isolated resonance groups around the He (2, 6a) 1Po and (2, 6a) 1De resonance pair in the small-field region.}, number={2}, journal={JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS}, author={Chung, KT and Fang, TK and Ho, YK}, year={2001}, month={Jan}, pages={165–174} }
 @article{chung_chang_2000, title={Structure of complex atom and photoionization of lithium below Li+ 1s3s S-3 - art. no. 030701}, volume={6103}, number={3}, journal={Physical Review. A}, author={Chung, K. T. and Chang, J. C.}, year={2000}, pages={0701} }
 @article{chung_chu_2000, title={Two-photon detachment of H-}, volume={61}, ISSN={["1094-1622"]}, DOI={10.1103/physreva.61.060702}, abstractNote={A precision calculation of the two-photon detachment cross section for H 2 is performed by means of a non-Hermitian Floquet theory. A highly accurate initial state wave function is used along with fully correlated saddle-point wave functions for the intermediate and final states. The cross section is investigated for energies below then52 andn53 thresholds. The peak cross section predicted for the D resonance is 3.10 310 cm sec at 10.873 2 eV. It represents an b initio theoretical prediction in complete agreement with the experimental result of 3.2 ( 11.8,21.2)310 cm sec at 10.873 2 ~ 7! eV.}, number={6}, journal={PHYSICAL REVIEW A}, author={Chung, KT and Chu, SI}, year={2000}, month={Jun} }
 @article{chung_1999, title={Auger decay of multiply excited atomic systems}, volume={59}, ISSN={["1094-1622"]}, DOI={10.1103/PhysRevA.59.2065}, abstractNote={By studying the branching ratios in the Auger decay of many triply excited three-electron atomic systems, we try to discover the physical reason behind the relative magnitude of the partial widths. It appears that Auger decay is most likely to happen when the two interacting electrons are in close proximity and the overlap of their charge distribution is significant in coordinate space. It is also pointed out that when an ${\mathrm{nl}}_{1}{\mathrm{nl}}_{2}{n}^{\ensuremath{'}}{l}_{3}{(n}^{\ensuremath{'}}>n>~2)$ state decays into an ${n}^{\ensuremath{''}}{l}_{1}{n}^{\ensuremath{'}}{l}_{3}(n>{n}^{\ensuremath{''}})+\ensuremath{\epsilon}{l}_{2}$ channel, the ${n}^{\ensuremath{'}}{l}_{3}$ orbital of the initial state is more diffused than that of the two-electron target. Therefore, some ${n}^{\ensuremath{''}}{l}_{1}{\mathrm{ml}}_{3}(m>{n}^{\ensuremath{'}})+\ensuremath{\epsilon}{l}_{2}$ channels will also contribute significantly to the Auger width of this state. The argument presented in this work is also applied to two- and four-electron systems. Explicit examples are presented.}, number={3}, journal={PHYSICAL REVIEW A}, author={Chung, KT}, year={1999}, month={Mar}, pages={2065–2070} }
 @article{kuan_jiang_chung_1999, title={Photodetachment of H-}, volume={60}, ISSN={["1094-1622"]}, DOI={10.1103/PhysRevA.60.364}, abstractNote={In a recent experiment [Andersen et al., Phys. Rev. Lett. 79, 4770 (1997)], the ${\mathrm{H}}^{\ensuremath{-}}$ photodetachment cross section (PDCS) and resonances are measured to high precision. Detailed resonance profiles are obtained. To make a critical comparison with experiment, the ${\mathrm{H}}^{\ensuremath{-}}$ PDCS below the $n=2$ and $n=3$ thresholds is calculated with a saddle-point complex-rotation method. The theoretical PDCS are convoluted with a Gaussian profile using experimental resolution for full width at half maximum. The theoretical results are calculated with length, velocity, and acceleration gauges. They are compared with the precision data in the literature. Improved widths are obtained for some of the narrow resonances below the $n=3$ threshold.}, number={1}, journal={PHYSICAL REVIEW A}, author={Kuan, WH and Jiang, TF and Chung, KT}, year={1999}, month={Jul}, pages={364–369} }
 @article{zhang_chung_1998, title={2s(2)2p P-2(o) triply excited state of He-}, volume={58}, ISSN={["1094-1622"]}, DOI={10.1103/PhysRevA.58.3336}, abstractNote={The triply excited ${2s}^{2}2p{}^{2}{P}^{o}$ state of ${\mathrm{He}}^{\ensuremath{-}}$ is studied by using the saddle-point complex-rotation method. The energy and Auger width of this resonance are calculated. Relativistic corrections are evaluated with the first-order perturbation theory, and the mass-polarization effect is also included. The partial Auger widths are calculated for the individual open channels. The total width is obtained by coupling the important open channels and summing over the other channels. These results are compared with the theoretical and experimental data in the literature.}, number={4}, journal={PHYSICAL REVIEW A}, author={Zhang, Y and Chung, KT}, year={1998}, month={Oct}, pages={3336–3337} }
 @article{chung_1998, title={Channel coupling and exchange interaction in negative ions}, volume={58}, ISSN={["1094-1622"]}, DOI={10.1103/PhysRevA.58.2777}, abstractNote={The effects of channel coupling and exchange interaction on the formation of resonances in negative ions are studied by solving the Schr\"odinger equation with an approximate wave function. These wave functions are constructed with very accurate target state wave functions which are frozen in the computation. The energy obtained is plotted against the radial expectation values of the approximate solutions. This leads to plots which are very similar to the conventional potential curve plots. However, by successively including the relevant target channels, the reason behind the formation or nonformation of a certain resonance becomes very clear. To illustrate, we show the results for nine ${\mathrm{He}}^{\ensuremath{-}}$ and two ${\mathrm{H}}^{2\ensuremath{-}}$ states.}, number={4}, journal={PHYSICAL REVIEW A}, author={Chung, KT}, year={1998}, month={Oct}, pages={2777–2786} }
 @article{chung_lin_1998, title={Doubly excited states of Li+ below the N=2 and N=3 thresholds of Li2+}, volume={69}, ISSN={["0092-640X"]}, DOI={10.1006/adnd.1998.0772}, abstractNote={Abstract Over 540 doubly excited Li+resonances below the Li2+N= 2 andN= 3 thresholds are studied with the complex-rotation method. The resonance energy, autoionization width, relativistic correction to the energy, and mass polarization are tabulated for each state. The doubly excited states are grouped into Rydberg series labeled by the quantum numbersK,T, andAto display the systematic regularity along the series. The calculated resonance energies are expected to be accurate to within a few meV.}, number={1}, journal={ATOMIC DATA AND NUCLEAR DATA TABLES}, author={Chung, KT and Lin, CD}, year={1998}, month={May}, pages={101–124} }
 @article{zhang_chung_1998, title={Even-parity triply excited states of lithium}, volume={58}, ISSN={["1094-1622"]}, DOI={10.1103/PhysRevA.58.1098}, abstractNote={In this work, 14 even-parity ${2l2l}^{\ensuremath{'}}{\mathrm{nl}}^{\ensuremath{''}}$ $(ng~3)$ resonances of lithium are calculated by using the saddle-point complex-rotation method. Among the 14 resonances, four are ${}^{2}P$ resonances, four are ${}^{2}D$ resonances, and six are ${}^{2}S$ resonances. Relativistic corrections are evaluated with the first-order perturbation theory and the mass-polarization effect is also included. The Auger widths are studied. The partial Auger widths are calculated for the individual open channels and the total width is obtained by coupling the important open channels. These results are compared with recent theoretical and experimental data in the literature.}, number={2}, journal={PHYSICAL REVIEW A}, author={Zhang, Y and Chung, KT}, year={1998}, month={Aug}, pages={1098–1102} }
 @article{chung_gou_1998, title={Identification of 2l2l ' nl '' P-2(0) hollow lithium systems}, volume={15}, ISSN={["1741-3540"]}, DOI={10.1088/0256-307X/15/5/008}, abstractNote={In a recent letter [L. Journel et al., Phys. Rev. Lett. 76, 30 (1996)], first experimental determination of the partial photoionization cross sections of lithium near the hollow atomic states was reported. Very extensive R-matrix calculation has also been carried out for the 'nl" 2P0 hollow states and assignments for the excited states have been made. However, these assignments are substantially different from those of other theoretical methods. This points out the need for more information and discussion which are necessary for a meaningful comparison.}, number={5}, journal={CHINESE PHYSICS LETTERS}, author={Chung, KT and Gou, BC}, year={1998}, pages={332–334} }
 @article{chung_1998, title={Photoionization of lithium from the 1s(2)2p state}, volume={57}, ISSN={["1094-1622"]}, DOI={10.1103/PhysRevA.57.3518}, abstractNote={The ${}^{2}S$ and ${}^{2}D$ photoionization cross section (PICS) of lithium from the ${1s}^{2}2p$ state is calculated for photon energies below the ${\mathrm{Li}}^{+}$ $1s2s{}^{1}S$ threshold. Forty-seven resonances are predicted. All the important PICS peaks predicted are found to be associated with the spectral lines observed in the high precision experiment. Although the agreement between theory and experiment is excellent in most cases, there are some interesting exceptions. The possible sources of these discrepancies are discussed. An important discrepancy in the earlier experiments is resolved. Several new identifications are made. Some of the observed lines are reassigned.}, number={5}, journal={PHYSICAL REVIEW A}, author={Chung, KT}, year={1998}, month={May}, pages={3518–3522} }
 @article{wu_chung_1997, title={P-2(0) resonances of the lithium atom in the inelastic scattering region}, volume={30}, ISSN={["1361-6455"]}, DOI={10.1088/0953-4075/30/5/012}, abstractNote={Recently, Kiernan and co-workers observed many new resonances in the inelastic scattering region in a high-resolution synchrotron radiation experiment. They also reported the energy (64.569(10) eV) and width (0.1 eV) for the lowest resonance, . In this work, we carried out multichannel saddle-point complex-rotation calculations for the 15 resonances between the and thresholds. Relativistic corrections are included. Our results for the , 3s energy and width are 64.568 and 0.117 eV, thus confirming the identification of the experiment unambiguously. However, we found that the structure observed near 65.2 eV is also caused by a resonance at 65.152 eV with a width of 89.7 meV. Our results agree with experiment except for the state. We found the position of this state to be below the threshold.}, number={5}, journal={JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS}, author={Wu, LJ and Chung, KT}, year={1997}, month={Mar}, pages={1173–1178} }
 @article{diehl_cubaynes_chung_wuilleumier_kennedy_bizau_journel_blancard_voky_faucher_et al._1997, title={Photoelectron spectroscopy measurements and theoretical calculations of the lowest doubly hollow lithium state}, volume={56}, ISSN={["1094-1622"]}, DOI={10.1103/PhysRevA.56.R1071}, abstractNote={We have measured, using electron spectroscopy, the lowest-energy doubly hollow lithium triply excited (3l3l′3l″) 2P state. Energies, widths, and partial cross sections have been measured and calculated using the saddle-point technique and the R-matrix approximation. Our results show good agreement between experimental and theoretical data for the energy and the width of the doubly hollow state.}, number={2}, journal={PHYSICAL REVIEW A}, author={Diehl, S and Cubaynes, D and Chung, KT and Wuilleumier, FJ and Kennedy, ET and Bizau, JM and Journel, L and Blancard, C and VoKy, L and Faucher, P and et al.}, year={1997}, month={Aug}, pages={R1071–R1074} }
 @article{chung_1997, title={Photoionization of lithium below the Li+ 1s2s S-3 threshold}, volume={56}, ISSN={["1094-1622"]}, DOI={10.1103/PhysRevA.56.R3330}, abstractNote={A saddle-point complex-rotation method is used to calculate the resonance energy, width, and photoionization cross section (PICS) of lithium below the ${\mathrm{Li}}^{+}$ $1s2s$${}^{3}S$ threshold. Fourteen ${}^{2}{P}^{o}$ resonances are studied. These results are compared with the most precise experimental data in the literature. Most of the Auger widths of these resonances are extremely narrow, which makes a direct theory-experiment PICS comparison difficult. However, if we convolute the predicted cross section with a Gaussian profile using the experimental resolution for full width at half maximum, the resulting profile agrees closely with the high-resolution photoion measurement.}, number={5}, journal={PHYSICAL REVIEW A}, author={Chung, KT}, year={1997}, month={Nov}, pages={R3330–R3333} }
 @article{chung_1997, title={Photoionization of lithium in the inelastic scattering region}, volume={78}, ISSN={["0031-9007"]}, DOI={10.1103/PhysRevLett.78.1416}, abstractNote={The photoionization of lithium to energies between the Li{sup +} 1s2s{sup 3}S and 1s2p{sup 1}P thresholds is studied with accurate ground and target state wave functions. Saddle-point full-core plus correlation wave functions are used for the closed channel. The result agrees with recent photoion measurements. Thirty nine resonances are found in the observed spectra and the predicted sharp peaks agree with experiment to meV levels. The predicted line profile agrees closely with experiment. Several earlier identifications are reassigned. Strong mixing of different resonance series is also found in a few instances. {copyright} {ital 1997} {ital The American Physical Society}}, number={8}, journal={PHYSICAL REVIEW LETTERS}, author={Chung, KT}, year={1997}, month={Feb}, pages={1416–1419} }
 @article{chung_1997, title={The physics of hollow lithium atom}, volume={35}, number={4}, journal={Chinese Journal of Physics [Taiwan]}, author={Chung, K. T.}, year={1997}, pages={453–461} }