537 results on '"Wong, K. T."'
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2. Absence, Disappearance, and Obfuscation: Contouring the US Anime Market through the Nonpresences in Crunchyroll's Yaoi Catalog
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Wong, K. T.
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- 2020
3. Chemical tracers of a highly eccentric AGB-main sequence star binary
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Danilovich, T., Malfait, J., Van de Sande, M., Montargès, M., Kervella, P., De Ceuster, F., Coenegrachts, A., Millar, T. J., Richards, A. M. S., Decin, L., Gottlieb, C. A., Pinte, C., De Beck, E., Price, D. J., Wong, K. T., Bolte, J., Menten, K. M., Baudry, A., de Koter, A., Etoka, S., Gobrecht, D., Gray, M., Herpin, F., Jeste, M., Lagadec, E., Maes, S., McDonald, I., Marinho, L., Müller, H. S. P., Pimpanuwat, B., Plane, J. M. C., Sahai, R., Wallström, S. H. J., Yates, J., and Zijlstra, A.
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Astrophysics - Solar and Stellar Astrophysics - Abstract
Binary interactions have been proposed to explain a variety of circumstellar structures seen around evolved stars, including asymptotic giant branch (AGB) stars and planetary nebulae. Studies resolving the circumstellar envelopes of AGB stars have revealed spirals, discs and bipolar outflows, with shaping attributed to interactions with a companion. For the first time, we have used a combined chemical and dynamical analysis to reveal a highly eccentric and long-period orbit for W Aquilae, a binary system containing an AGB star and a main sequence companion. Our results are based on anisotropic SiN emission, the first detections of NS and SiC towards an S-type star, and density structures observed in the CO emission. These features are all interpreted as having formed during periastron interactions. Our astrochemistry-based method can yield stringent constraints on the orbital parameters of long-period binaries containing AGB stars, and will be applicable to other systems., Comment: This version of the article has been accepted for publication, after peer review (when applicable) and is subject to Springer Nature's AM terms of use, but is not the Version of Record and does not reflect post-acceptance improvements, or any corrections. The Version of Record is available online at: https://doi.org/10.1038/s41550-023-02154-y
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- 2024
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4. ATOMIUM: Molecular inventory of 17 oxygen-rich evolved stars observed with ALMA
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Wallstrom, S. H. J., Danilovich, T., Muller, H. S. P., Gottlieb, C. A., Maes, S., Van de Sande, M., Decin, L., Richards, A. M. S., Baudry, A., Bolte, J., Ceulemans, T., De Ceuster, F., de Koter, A., Mellah, I. El, Esseldeurs, M., Etoka, S., Gobrecht, D., Gottlieb, E., Gray, M., Herpin, F., Jeste, M., Kee, D., Kervella, P., Khouri, T., Lagadec, E., Malfait, J., Marinho, L., McDonald, I., Menten, K. M., Millar, T. J., Montarges, M., Nuth, J. A., Plane, J. M. C., Sahai, R., Waters, L. B. F. M., Wong, K. T., Yates, J., and Zijlstra, A.
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Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
The dusty winds of cool evolved stars are a major contributor of the newly synthesised material enriching the Galaxy and future generations of stars. However, the details of the physics and chemistry behind dust formation and wind launching have yet to be pinpointed. Recent spatially resolved observations show the importance of gaining a more comprehensive view of the circumstellar chemistry, but a comparative study of the intricate interplay between chemistry and physics is still difficult because observational details such as frequencies and angular resolutions are rarely comparable. Aiming to overcome these deficiencies, ATOMIUM is an ALMA Large Programme to study the physics and chemistry of the circumstellar envelopes of a diverse set of oxygen-rich evolved stars under homogeneous observing conditions at three angular resolutions between ~0.02"-1.4". Here we summarize the molecular inventory of these sources, and the correlations between stellar parameters and molecular content. Seventeen oxygen-rich or S-type asymptotic giant branch (AGB) and red supergiant (RSG) stars have been observed in several tunings with ALMA Band 6, targeting a range of molecules to probe the circumstellar envelope and especially the chemistry of dust formation close to the star. We systematically assigned the molecular carriers of the spectral lines and measured their spectroscopic parameters and the angular extent of the emission of each line from integrated intensity maps. Across the ATOMIUM sample, we detect 291 transitions of 24 different molecules and their isotopologues. This includes several first detections in oxygen-rich AGB/RSG stars: PO v=1, SO2 v1=1 and v2=2, and several high energy H2O transitions. We also find several first detections in S-type AGB stars: vibrationally excited HCN v2=2,3 and SiS v=4,5,6, as well as first detections of the molecules SiC, AlCl, and AlF in W Aql..., Comment: 19 pages plus appendices, forthcoming publication in Astronomy & Astrophysics
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- 2023
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5. ATOMIUM: Probing the inner wind of evolved O-rich stars with new, highly excited H$_2$O and OH lines
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Baudry, A., Wong, K. T., Etoka, S., Richards, A. M. S., Muller, H. S. P., Herpin, F., Danilovich, T., Gray, M. D., Wallstrom, S., Gobrecht, D., Khouri, T., Decin, L., Gottlieb, C. A., Menten, K. M., Homan, W., Millar, T. J., Montarges, M., Pimpanuwat, B., Plane, J. M. C., and Kervella, P.
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Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
Water and the hydroxyl radical are major constituents of the envelope of O-rich late-type stars. Transitions involving energy levels that are highly excited have been observed in both H$_2$O and OH. These and more recently discovered transitions can now be observed at a high sensitivity and angular resolution with the ALMA Array. Spectra and maps of H$_2$O and OH observed with an angular resolution of 20 to $\sim$200 mas were obtained at two epochs with the ALMA array. Observations with the Compact Array were also used to check for time variability of water transitions. Radiative transfer models of water were revisited to characterize masing conditions and up-to-date chemical models were used for comparison with our observations. Ten rotational transitions of H$_2$O with energies up to 9000 K were observed in various vibrational states. All but one are new detections in space, and from these we have derived accurate rest frequencies. Hyperfine split $\Lambda$-doubling transitions in v = 0, J = 27/2 and 29/2 levels of the $^2\Pi_{3/2}$ state and, $J = 33/2$ and 35/2 of the $^2\Pi_{1/2}$ state of OH with excitation energies up to 8900 K were also observed. Four of these transitions are new detections in space. Combining our measurements with earlier observations of OH, the v = 0 and v = 1 $\Lambda$-doubling frequencies have been improved. Our H$_2$O maps show compact emission and extensions up to twelve stellar radii or more. The 268.149 GHz emission line of water in the v$_2$ = 2 state is time variable, tends to be masing with dominant radiative pumping, and is widely excited. The widespread but weaker 262.898 GHz water line in v$_2$ = 1 also shows signs of maser emission. Emission and absorption of both H$_2$O and OH reveal an infall of matter and complex kinematics influenced by binarity. From our observed column densities, we derived OH/H$_2$O abundance ratios in a few stars., Comment: 41 pages with references and 25 figures in main text. 4 Tables in Appendix A. 10 figures in Appendix B. 2 figures in Appendix C. 14 figures in Appendix D. 5 figures in Appendix E. 2 figures in Appendix F
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- 2023
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6. The VLT/SPHERE view of the ATOMIUM cool evolved star sample. I. Overview: Sample characterization through polarization analysis
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Montargès, M., Cannon, E., de Koter, A., Khouri, T., Lagadec, E., Kervella, P., Decin, L., McDonald, I., Homan, W., Waters, L. B. F. M., Sahai, R., Gottlieb, C. A., Malfait, J., Maes, S., Pimpanuwat, B., Jeste, M., Danilovich, T., De Ceuster, F., Van de Sande, M., Gobrecht, D., Wallström, S. H. J., Wong, K. T., Mellah, I. El, Bolte, J., Herpin, F., Richards, A. M. S., Baudry, A., Etoka, S., Gray, M. D., Millar, T. J., Menten, K. M., Müller, H. S. P., Plane, J. M. C., Yates, J., and Zijlstra, A.
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Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
Aims. Through the ATOMIUM project, based on an ALMA large program, we aim to present a consistent view of a sample of 17 nearby cool evolved stars (Aymptotic Giant Branch and red supergiant stars). Methods. Here we present VLT/SPHERE-ZIMPOL polarimetric maps obtained in the visible of 14 out of the 17 ATOMIUM sources. They were obtained contemporaneously with the ALMA high spatial resolution data. To help interpret the polarized signal, we produced synthetic maps of light scattering by dust, through 3D radiative transfer simulations with the RADMC3D code. Results. The degree of linear polarization (DoLP) observed by ZIMPOL spreads across several optical filters. We infer that it primarily probes dust located just outside of the point spread function, and in or near the plane of the sky, with a total optical depth close to unity in the line of sight, representing only a fraction of the total circumstellar dust. The maximum DoLP ranges from 0.03-0.38 depending on the source, fractions that can be reproduced by our 3D pilot models for grains composed of common dust species. The spatial structure of the DoLP shows a diverse set of shapes. Only for three sources do we note a correlation between the ALMA CO and SiO lines, which trace the gas density, and the DoLP, which traces the dust. Conclusion. The clumpiness of the DoLP and the lack of a consistent correlation between the gas and the dust location show that, in the inner circumstellar environment (CSE), dust formation occurs at very specific sites. This has potential consequences for the derived mass-loss rates and dust-to-gas ratio in the inner region of the CSE. Except for $\pi^1$~Gru and perhaps GY Aql, we do not detect interactions between the circumstellar wind and the hypothesized companions that shape the wind at larger scales. This suggests that the orbits of any other companions are tilted out of the plane of the sky., Comment: Accepted for publication in Astronomy & Astrophysics. 22 pages, 15 figures, 5 tables
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- 2023
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7. ATOMIUM: ALMA tracing the origins of molecules in dust forming oxygen rich M-type stars: Motivation, sample, calibration, and initial results
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Gottlieb, C. A., Decin, L., Richards, A. M. S., De Ceuster, F., Homan, W., Wallstrom, S. H. J., Danilovich, T., Millar, T. J., Montarges, M., Wong, K. T., McDonald, I., Baudry, A., Bolte, J., Cannon, E., De Beck, E., de Koter, A., Mellah, I. El, Etoka, S., Gobrecht, D., Gray, M., Herpin, F., Jeste, M., Kervella, P., Khouri, T., Lagadec, E., Maes, S., Malfait, J., Menten, K. M., Muller, H. S. P., Pimpanuwat, B., Plane, J. M. C., Sahai, R., Van de Sande, M., Waters, L. B. F. M., Yates, J., and Zijlstra, A.
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Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
This overview paper presents ATOMIUM, a Large Programme in Cycle 6 with the Atacama Large Millimeter-submillimeter Array (ALMA). The goal of ATOMIUM is to understand the dynamics and the gas phase and dust formation chemistry in the winds of evolved asymptotic giant branch (AGB) and red supergiant (RSG) stars. A more general aim is to identify chemical processes applicable to other astrophysical environments. 17 oxygen-rich AGB and RSG stars spanning a range in (circum)stellar parameters and evolutionary phases were observed in a homogeneous observing strategy allowing for an unambiguous comparison. Data were obtained between 213.83 and 269.71 GHz at high (0.025-0.050 arcsec), medium (0.13-0.24 arcsec), and low (about 1 arcsec) angular resolution. The sensitivity per 1.3 km/s channel was 1.5-5 mJy/beam. 13 molecules were designated as primary molecules in the survey: CO, SiO, AlO, AlOH, TiO, TiO2, HCN, SO, SO2, SiS, CS, H2O, and NaCl. The scientific motivation, survey design, sample properties, data reduction, and an overview of the data products are described; and we highlight one scientific result - the wind kinematics of the ATOMIUM sources. The ATOMIUM sources often have a slow wind acceleration, and a fraction of the gas reaches a velocity which can be up to a factor of two times larger than previously reported terminal velocities assuming isotropic expansion, and the wind kinematic profiles establish that the radial velocity described by the momentum equation for a spherical wind structure cannot capture the complexity of the velocity field. In 15 sources, some molecular transitions other than 12CO v=0 J=2-1 reach a higher outflow velocity, with a spatial emission zone that is often greater than 30 stellar radii, but much less than the extent of CO. Binary interaction with a (sub)stellar companion might (partly) explain the non-monotonic behaviour of the projected velocity field.
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- 2021
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8. Molecules, shocks, and disk in the axi-symmetric wind of the MS-type AGB star RS Cancri
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Winters, J. M., Hoai, D. T., Wong, K. T., Kim, W., Nhung, P. T., Tuan-Anh, P., Lesaffre, P., Darriulat, P., and Bertre, T. Le
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Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
The latest evolutionary phases of low- and intermediate mass stars are characterized by complex physical processes like turbulence, convection, stellar pulsations, magnetic fields, condensation of solid particles, and the formation of massive outflows that inject freshly produced heavy elements and dust particles into the interstellar medium. We use the Northern Extended Millimeter Array (NOEMA) to obtain spatially and spectrally resolved observations of the semi-regular Asymptotic Giant Branch star RS Cancri to shed light on the morpho-kinematic structure of its inner, wind forming environment by applying detailed 3-D reconstruction modeling and LTE radiative transfer calculations. We detect 32 lines of 13 molecules and isotopologs (CO, SiO, SO, SO$_2$, H$_2$O, HCN, PN), including several transitions from vibrationally excited states. HCN, H$^{13}$CN, millimeter vibrationally excited H$_2$O, SO, $^{34}$SO, SO$_2$, and PN are detected for the first time in RS Cnc. Evidence for rotation is seen in HCN, SO, SO$_2$, and SiO(v=1). From CO and SiO channel maps, we find an inner, equatorial density enhancement, and a bipolar outflow structure with a mass loss rate of $1 \times 10^{-7}M_\odot{\rm yr}^{-1}$ for the equatorial region and of $2 \times 10^{-7}M_\odot{\rm yr}^{-1}$ for the polar outflows. The $^{12}$CO/$^{13}$CO ratio is measured to be $\sim20$ on average, $24\pm2$ in the polar outflows and $19\pm3$ in the equatorial region. We do not find direct evidence of a companion that might explain this kind of kinematic structure, and explore the possibility that a magnetic field might be the cause of it. The innermost molecular gas is influenced by stellar pulsation and possibly by convective cells that leave their imprint on broad wings of certain molecular lines, such as SiO and SO., Comment: 28 pages, 40 figures, accepted for publication in Astronomy & Astrophysics
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- 2021
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9. ATOMIUM: Halide molecules around the S-type AGB star W Aquilae
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Danilovich, T., Van de Sande, M., Plane, J. M. C., Millar, T. J., Royer, P., Amor, M. A., Hammami, K., Decock, L., Gottlieb, C. A., Decin, L., Richards, A. M. S., De Beck, E., Baudry, A., Bolte, J., Cannon, E., De Ceuster, F., de Koter, A., Etoka, S., Gobrecht, D., Gray, M., Herpin, F., Homan, W., Jeste, M., Kervella, P., Khouri, T., Lagadec, E., Maes, S., Malfait, J., McDonald, I., Menten, K. M., Montargès, M., Müller, H. S. P., Pimpanuwat, B., Sahai, R., Wallström, S. H. J., Waters, L. B. F. M., Wong, K. T., Yates, J., and Zijlstra, A.
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Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
S-type asymptotic giant branch (AGB) stars are thought to be intermediates in the evolution of oxygen- to carbon-rich AGB stars. The chemical compositions of their circumstellar envelopes are also intermediate, but have not been studied in as much detail as their carbon- and oxygen-rich counterparts. We aim to determine the abundances of AlCl and AlF from rotational lines, which have been observed for the first time towards an S-type AGB star, W Aql. In combination with models based on PACS observations, we aim to update our chemical kinetics network based on these results. We analyse ALMA observations towards W Aql of AlCl in the ground and first two vibrationally excited states and AlF in the ground vibrational state. Using radiative transfer models, we determine the abundances and spatial abundance distributions of Al$^{35}$Cl, Al$^{37}$Cl, and AlF. We also model HCl and HF emission and compare these models to PACS spectra to constrain the abundances of these species. AlCl is found in clumps very close to the star, with emission confined within 0.1$^{\prime\prime}$ of the star. AlF emission is more extended, with faint emission extending 0.2$^{\prime\prime}$ to 0.6$^{\prime\prime}$ from the continuum peak. We find peak abundances, relative to H$_2$, of $1.7\times 10^{-7}$ for Al$^{35}$Cl, $7\times 10^{-8}$ for Al$^{37}$Cl and $1\times 10^{-7}$ for AlF. From the PACS spectra, we find abundances of $9.7\times 10^{-8}$ and $\leq 10^{-8}$, relative to H$_2$, for HCl and HF, respectively. The AlF abundance exceeds the solar F abundance, indicating that fluorine synthesised in the AGB star has already been dredged up to the surface of the star and ejected into the circumstellar envelope. From our analysis of chemical reactions in the wind, we conclude that AlF may participate in the dust formation process, but we cannot fully explain the rapid depletion of AlCl seen in the wind., Comment: Accepted for publication in Astronomy & Astrophysics
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- 2021
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10. Towards a global partnership model in interprofessional education for cross-sector problem-solving
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Ganotice, Jr, Fraide, Zheng, Binbin, Ng, Pauline Yeung, Leung, Siu Chung, Barrett, Elizabeth Ann, Chan, Hoi Yan Celia, Chan, Chad W. N., Chan, Kit Wa Sherry, Chan, Linda, Chan, M. K. Karen, Chan, Siu Ling Polly, Chan, So Ching Sarah, Chan, Esther W. Y., Chen, Julie, Cheuk, Yuet Ying Jessica, Chong, Yin Kei Doris, Chow, Yin Man Amy, Chu, Kwok Pui Jody, Chung, Hon Yin Brian, Ho, Shun Yee Amy, Jen, Julienne, Jin, Jingwen, Khoo, Ui Soon, Lam, Ho Yan Angie, Lam, May P. S., Lam, Suk Fun Veronica, Lee, Pamela Pui-Wah, Lee, Jetty Chung-Yung, Leung, Chung Yin Feona, Leung, Anna K. Y., Lin, Xiang, Liu, Rebecca K. W., Lou, Wei Qun Vivian, Luk, Pauline, Ng, Lai Han Zoe, Ng, Yee Man Alina, Ng, Tin Wai Terry, See, Lok Man Mary, Shen, Jiangang, Shen, Xiaoai, Szeto, Grace, Tam, Eliza Y. T., To, Kelvin Kai-Wang, Tso, Wan-Yee Winnie, Vackova, Dana, Wang, Ning, Wang, Runjia, Wong, Hoi Yan Gloria, Wong, K. T. Janet, Wong, M. Y. Anita, Wong, Yuen Ha Janet, Yuen, Kwan Yuk Jacqueline, Yuen, Wai Yee Grace, Orlu, Mine, and Tipoe, George L.
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- 2023
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11. (Sub)stellar companions shape the winds of evolved stars
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Decin, L., Montargès, M., Richards, A. M. S., Gottlieb, C. A., Homan, W., McDonald, I., Mellah, I. El, Danilovich, T., Wallström, S. H. J., Zijlstra, A., Baudry, A., Bolte, J., Cannon, E., De Beck, E., De Ceuster, F., de Koter, A., De Ridder, J., Etoka, S., Gobrecht, D., Gray, M., Herpin, F., Jeste, M., Lagadec, E., Kervella, P., Khouri, T., Menten, K., Millar, T. J., Müller, H. S. P., Plane, J. M. C., Sahai, R., Sana, H., Van de Sande, M., Waters, L. B. F. M., Wong, K. T, and Yates, J.
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Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
Binary interactions dominate the evolution of massive stars, but their role is less clear for low- and intermediate-mass stars. The evolution of a spherical wind from an asymptotic giant branch (AGB) star into a nonspherical planetary nebula (PN) could be due to binary interactions. We observed a sample of AGB stars with the Atacama Large Millimeter/submillimeter Array (ALMA) and found that their winds exhibit distinct nonspherical geometries with morphological similarities to planetary nebulae (PNe). We infer that the same physics shapes both AGB winds and PNe; additionally, the morphology and AGB mass-loss rate are correlated. These characteristics can be explained by binary interaction. We propose an evolutionary scenario for AGB morphologies that is consistent with observed phenomena in AGB stars and PNe., Comment: 19 pages main journal, 97 pages Supplementary Information
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- 2020
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12. Molecular remnant of Nova 1670 (CK Vulpeculae): I. Properties and enigmatic origin of the gas
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Kaminski, T., Menten, K. M., Tylenda, R., Wong, K. T., Belloche, A., Mehner, A., Schmidt, M. R., and Patel, N. A.
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Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
CK Vul erupted in 1670 and is considered a stellar-merger candidate. Its remnant contains a molecular component of surprisingly rich composition. We present interferometric line surveys with subarcsec resolution with ALMA and SMA. The observations provide interferometric maps of molecular line emission at frequencies between 88 and 243 GHz that allow imaging spectroscopy of more than 180 transitions of 26 species. We present, classify, and analyze the different morphologies of the emission regions displayed by the molecules. We also perform a non-LTE radiative-transfer analysis of emission of most of the observed species, deriving temperatures and column densities in five parts of the nebula. Non-LTE effects are clearly seen in complex species including methanol absorption against the CMB. The temperatures are 17 K in the inner remnant and 14 K in the extended lobes. We find total (hydrogen plus helium) densities in the range of $10^4-10^6$ cm$^{-3}$. The column densities provide relative abundance patterns in the remnant which currently are not understood. Attempts to derive elemental abundances within the assumption of a chemical equilibrium give only loose constraints on the CNO elements. That the formation of many of the observed molecules requires a major involvement of circumstellar shocks remains the preferred possibility. The molecular gas could have formed 350 yr ago or more recently. The molecules are well shielded from the interstellar radiation field by the circumstellar dust. Their presence alone indicates that the unobservable central star cannot be a hot object such as a white dwarf. This excludes some of the proposed scenarios on the nature of CK Vul. The general characteristics of the molecular environment of CK Vul derived in this study resemble quite well those of some pre-planetary nebulae and AGB stars, most notably that of OH231.8., Comment: submitted to A&A; comments welcome
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- 2020
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13. Circumstellar ammonia in oxygen-rich evolved stars
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Wong, K. T., Menten, K. M., Kamiński, T., Wyrowski, F., Lacy, J. H., and Greathouse, T. K.
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Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
The circumstellar ammonia (NH$_3$) chemistry in evolved stars is poorly understood. Previous observations and modelling showed that NH$_3$ abundance in oxygen-rich stars is several orders of magnitude above that predicted by equilibrium chemistry. In this article, we characterise the spatial distribution and excitation of NH$_3$ in the O-rich circumstellar envelopes (CSEs) of four diverse targets: IK Tau, VY CMa, OH 231.8+4.2, and IRC +10420 with multi-wavelength observations. We observed the 1.3-cm inversion line emission with the Very Large Array (VLA) and submillimetre rotational line emission with the Heterodyne Instrument for the Far-Infrared (HIFI) aboard Herschel from all four targets. For IK Tau and VY CMa, we observed the rovibrational absorption lines in the $\nu_2$ band near 10.5 $\mu$m with the Texas Echelon Cross Echelle Spectrograph (TEXES) at the NASA Infrared Telescope Facility (IRTF). We also attempted to search for the rotational transition within the $v_2=1$ state near 2 mm with the IRAM 30m Telescope towards IK Tau. Non-LTE radiative transfer modelling, including radiative pumping to the vibrational state, was carried out to derive the radial distribution of NH$_3$ in these CSEs. Our modelling shows that the NH$_3$ abundance relative to molecular hydrogen is generally of the order of $10^{-7}$, which is a few times lower than previous estimates that were made without considering radiative pumping and is at least 10 times higher than that in the C-rich CSE of IRC +10216. Incidentally, we also derived a new period of IK Tau from its $V$-band light curve. NH$_3$ is again detected in very high abundance in O-rich CSEs. Its emission mainly arises from localised spatial-kinematic structures that are probably denser than the ambient gas. Circumstellar shocks in the accelerated wind may contribute to the production of NH$_3$. (Abridged abstract), Comment: 38 pages, 28 figures, 6 tables, accepted for publication in Astronomy and Astrophysics, cross-listed to astro-ph.GA as per request by arXiv
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- 2017
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14. Inter-Asian Gaming in Southeast Asia: Remapping the Globalization of Videogames through the Lens of Malaysia and Singapore
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Wong, K. T.
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Southeast Asian studies ,Multimedia communications - Abstract
The gaming landscape of Southeast Asia, dubbed by prominent market reports as “the world’s fastest growing games region,” has undergone profound transformation due to globalization since the late 1990s. Southeast Asia, however, remained an understudied region in game studies. Conversely, videogame as a medium is largely overlooked by scholars in Southeast Asian studies. Due to this gap, mainstream discourses about Southeast Asia vis-à-vis gaming are driven by industry rhetoric that frames the region as a new frontier to be exploited, neglecting the agency of Southeast Asians in shaping their own gaming culture and history.To remedy this issue, this project charts the evolution of Southeast Asian gaming culture from the perspective of Malaysia and Singapore between the 1990s and 2010s occasioned by the region’s integration into the global gaming economy in ways that foreground the agency of local entities, including players, developers, private companies, and state agencies. In particular, the late 2000s is an important turning point which marks the intensification of endeavors to formalize gaming activities from within the region. The elevation of videogames into an essential cultural and economic sector within the region, while brought on by foreign impetus, is increasingly driven by Southeast Asian entities, especially state governments invested in strengthening their positions in the global digital economy.This project proposes that Southeast Asia can serve as a framework to remap the globalization of videogames through the lens of regional integration, which allows for an alternative mode of knowledge production that recenters Southeast Asian autonomy. I name this framework the “Inter-Asian Gaming.” Inspired by Kuan-Hsing Chen’s “Asia as method,” Inter-Asian Gaming aims to decenter the West by focusing on regional gaming economy, including intra-regional cooperation within Southeast Asia and inter-regional exchanges with East Asia. I posit that a study of Southeast Asian gaming culture that centers on regional interconnections holds the potential to generate alternative understandings of non-Western gaming histories in relation to neighboring spaces instead of imperialist centers.
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- 2023
15. A Generalized Correlation Index for Quantifying Signal Morphological Similarity
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Olenko, A., Wong, K. T., Mir, H., and Al-Nashash, H.
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Statistics - Applications ,Statistics - Methodology ,92C55, 62P10, 62H20 - Abstract
In biomedical applications, the similarity between a signal measured from an injured subject and a reference signal measured from a normal subject can be used to quantify the injury severity. This paper proposes a generalization of the adaptive signed correlation index (ASCI) to account for specific signal features of interest and extend the trichotomization of conventional ASCI to an arbitrary number of levels. In the context of spinal cord injury assessment, a computational example is presented to illustrate the enhanced resolution of the proposed measure and its ability to offer a more refined measure of the level of injury., Comment: 2 two-column pages, 3 figures
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- 2016
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16. An observational study of dust nucleation in Mira ($o$ Ceti): II. Titanium oxides are negligible for nucleation at high temperatures
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Kamiński, T., Müller, H. S. P., Schmidt, M. R., Cherchneff, I., Wong, K. T., Brünken, S., Menten, K. M., Winters, J. M., Gottlieb, C. A., and Patel, N. A.
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Astrophysics - Solar and Stellar Astrophysics - Abstract
The formation of silicate dust in oxygen-rich envelopes of evolved stars is thought to be initiated by formation of seed particles that can withstand the high temperatures close to the stellar photosphere and act as condensation cores farther away from the star. Candidate species considered as first condensates are TiO and TiO$_2$. We aim to identify and characterize the circumstellar gas-phase chemistry of titanium that leads to the formation of solid titanium compounds in the envelope of $o$ Cet, the prototypical Mira, and seek an observational verification of whether titanium oxides play a major role in the onset of dust formation in M-type AGB stars. We present high angular-resolution ALMA observations at submillimeter (submm) wavelengths supplemented by APEX and Herschel spectra of the rotational features of TiO and TiO$_2$. In addition, circumstellar features of TiO and TiI are identified in optical spectra which cover multiple pulsation cycles of $o$ Cet. The submm ALMA data reveal TiO and TiO$_2$ bearing gas within the extended atmosphere of Mira. While TiO is traceable up to a radius (FWHM/2) of 4.0 R$_{\star}$, TiO$_2$ extends as far as 5.5 R$_{\star}$ and unlike TiO appears to be anisotropically distributed. Optical spectra display variable emission of TiI and TiO from inner parts of the extended atmosphere (<3 R$_{\star}$). Chemical models which include shocks are in general agreement with the observations of gas-phase titanium-bearing molecules. It is unlikely that substantial amounts of titanium is locked up in solids because the abundance of the gaseous titanium species is very high. In particular, formation of hot titanium-rich condensates is very improbable because we find no traces of their hot precursor species in the gas phase. It therefore appears unlikely that the formation of dust in Mira, and possibly other M-type AGB stars, is initiated by titanium oxides., Comment: 19 pages plus spectral atlas of the TiO gamma' band in 1998-2014 submitted to A&A
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- 2016
- Full Text
- View/download PDF
17. An observational study of dust nucleation in Mira ($o$ Ceti): I. Variable features of AlO and other Al-bearing species
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Kamiński, T., Wong, K. T., Schmidt, M. R., Müller, H. S. P., Gottlieb, C. A., Cherchneff, I., Menten, K. M., Keller, D., Brünken, S., Winters, J. M., and Patel, N. A.
- Subjects
Astrophysics - Solar and Stellar Astrophysics - Abstract
Context: Dust is efficiently produced by cool giant stars, but the condensation of inorganic dust is poorly understood. Aims: Identify and characterize aluminum bearing species in the circumstellar gas of Mira ($o$ Ceti) in order to elucidate their role in the production of Al$_2$O$_3$ dust. Methods: Multiepoch spectral line observations at (sub-)millimeter, far-infrared, and optical wavelengths including: maps with ALMA which probe the gas distribution in the immediate vicinity of the star at ~30 mas; observations with ALMA, APEX, and Herschel in 2013-2015 for studying cycle and inter-cycle variability of the rotational lines of Al bearing molecules; optical records as far back as 1965 to examine variations in electronic transitions over time spans of days to decades; and velocity measurements and excitation analysis of the spectral features which constrain the physical parameters of the gas. Results: Three diatomic molecules AlO, AlOH, and AlH, and atomic Al I are the main observable aluminum species in Mira, although a significant fraction of aluminum might reside in other species that have not yet been identified. Strong irregular variability in the (sub-)millimeter and optical features of AlO (possibly the direct precursor of Al$_2$O$_3$) indicates substantial changes in the excitation conditions, or varying abundance that is likely related to shocks in the star. The inhomogeneous distribution of AlO might influence the spatial and temporal characteristics of dust production. Conclusions: We are unable to quantitatively trace aluminum depletion from the gas, but the rich observational material constrains time dependent chemical networks. Future improvements should include spectroscopic characterization of higher aluminum oxides, coordinated observations of dust and gas species at different variability phases, and tools to derive abundances in shock excited gas., Comment: submitted to A&A, 23 pages plus an atlas of spectral variability of Mira in Al-bearing species since 1965 (90 pages total)
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- 2016
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18. Resolving the extended atmosphere and the inner wind of Mira ($o$ Ceti) with long ALMA baselines
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Wong, K. T., Kamiński, T., Menten, K. M., and Wyrowski, F.
- Subjects
Astrophysics - Solar and Stellar Astrophysics - Abstract
The prototypical Mira variable, $o$ Cet (Mira), has been observed as a Science Verification target in the 2014 ALMA Long Baseline Campaign with a longest baseline of 15 km. ALMA clearly resolves the images of the continuum and molecular line emission/absorption at an angular resolution of ~30 mas at 220 GHz. We image the data of the $^{28}$SiO v=0, 2 $J$=5-4 and H$_2$O $\nu_2$=1 $J(K_a,K_c)$=5(5,0)-6(4,3) transitions and extract spectra from various lines-of-sight towards Mira's extended atmosphere. In the course of imaging, we encountered ambiguities in the resulting images and spectra that appear to be related to the performance of the CLEAN algorithm. We resolve Mira's millimetre continuum emission and our data are consistent with a radio photosphere with a brightness temperature of 2611$\pm$51 K, in agreement with recent results obtained with the VLA. We do not confirm the existence of a compact region (<5 mas) of enhanced brightness. We derive the gas density, kinetic temperature, molecular abundance and outflow/infall velocities in Mira's extended atmosphere by modelling the SiO and H$_2$O lines. We find that SiO-bearing gas starts to deplete beyond 4$R_\star$ and at a kinetic temperature of $\lesssim$600 K. The inner dust shells are probably composed of grain types other than pure silicates. During this observation, Mira's atmosphere generally exhibited infall motion, with a shock front of velocity $\lesssim$12 km/s outside the radio photosphere. The structures predicted by the hydrodynamical model CODEX can reproduce the observed spectra in astonishing detail; while some other models fail when confronted with the new data. Combined with radiative transfer modelling, ALMA successfully demonstrates the ability to reveal the physical conditions of the extended atmospheres and inner winds of AGB stars in unprecedented detail. (Abbreviated abstract), Comment: 55 pages, 42 figures, accepted for publication in Astronomy and Astrophysics
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- 2016
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19. Novel thieno[3,2-b]thiophene-embedded small-molecule donors for highly efficient and photostable vacuum-processed organic photovoltaics
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Su, J.-M., Li, Y.-Z., Chang, Y.-H., Li, M.-Z., Qiu, W.-Z., Liu, S.-W., and Wong, K.-T.
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- 2021
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- View/download PDF
20. Chemical tracers of a highly eccentric AGB–main-sequence star binary
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Danilovich, T., primary, Malfait, J., additional, Van de Sande, M., additional, Montargès, M., additional, Kervella, P., additional, De Ceuster, F., additional, Coenegrachts, A., additional, Millar, T. J., additional, Richards, A. M. S., additional, Decin, L., additional, Gottlieb, C. A., additional, Pinte, C., additional, De Beck, E., additional, Price, D. J., additional, Wong, K. T., additional, Bolte, J., additional, Menten, K. M., additional, Baudry, A., additional, de Koter, A., additional, Etoka, S., additional, Gobrecht, D., additional, Gray, M., additional, Herpin, F., additional, Jeste, M., additional, Lagadec, E., additional, Maes, S., additional, McDonald, I., additional, Marinho, L., additional, Müller, H. S. P., additional, Pimpanuwat, B., additional, Plane, J. M. C., additional, Sahai, R., additional, Wallström, S. H. J., additional, Yates, J., additional, and Zijlstra, A., additional
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- 2024
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- View/download PDF
21. Bio-sorptive Removal of Methyl Orange by Micro-Grooved Chitosan (GCS) Beads: Optimization of Process Variables Using Taguchi L9 Orthogonal Array
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Wong, K. T., Wong, V. L., and Lim, S. S.
- Published
- 2021
- Full Text
- View/download PDF
22. ATOMIUM: Probing the inner wind of evolved O-rich stars with new, highly excited H2O and OH lines
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Baudry, A., primary, Wong, K. T., additional, Etoka, S., additional, Richards, A. M. S., additional, Müller, H. S. P., additional, Herpin, F., additional, Danilovich, T., additional, Gray, M. D., additional, Wallström, S., additional, Gobrecht, D., additional, Khouri, T., additional, Decin, L., additional, Gottlieb, C. A., additional, Menten, K. M., additional, Homan, W., additional, Millar, T. J., additional, Montargès, M., additional, Pimpanuwat, B., additional, Plane, J. M. C., additional, and Kervella, P., additional
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- 2023
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- View/download PDF
23. Is Kingdom Hearts a JRPG? The Racialized Labor of a Japanese Anti-auteur's Disney-Licensed Videogame.
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Wong, K. T.
- Subjects
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JAPANESE language , *QUEER theory , *POPULAR culture , *COMPULSIVE gambling , *HEART , *ODORS ,WALT Disney World (Fla.) - Abstract
This article examines the video game Kingdom Hearts and its classification as a Japanese role-playing game (JRPG) due to its collaboration with the Walt Disney Company. It explores the game's Japanese identity and the role of race in its production and the global video game industry. The article also discusses the erasure of minority labor in the industry and the importance of studying JRPGs to understand the racial politics of the industry. It analyzes the game's creator, Tetsuya Nomura, from the perspective of auteur theory and contrasts his auteurship with other game developers. The tensions between Disney and Square Enix in the development of Kingdom Hearts are explored, as well as the racialized labor of the creative team. The article also discusses the game's use of Disney animations and characters, including the creation of iconic landmarks and new environments. It explores the concept of the anti-auteur in the game industry. [Extracted from the article]
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- 2023
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24. Exploring the current and future role of the pharmacists in osteoporosis screening and management in Malaysia
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Toh, L. S., Lai, P. S. M., Othman, S., Shah, A., Dang, C. P. L., Low, B. Y., Wong, K. T., and Anderson, C.
- Published
- 2018
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25. The VLT/SPHERE view of the ATOMIUM cool evolved star sample
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Montargès, M., primary, Cannon, E., additional, de Koter, A., additional, Khouri, T., additional, Lagadec, E., additional, Kervella, P., additional, Decin, L., additional, McDonald, I., additional, Homan, W., additional, Waters, L. B. F. M., additional, Sahai, R., additional, Gottlieb, C. A., additional, Malfait, J., additional, Maes, S., additional, Pimpanuwat, B., additional, Jeste, M., additional, Danilovich, T., additional, De Ceuster, F., additional, Van de Sande, M., additional, Gobrecht, D., additional, Wallström, S. H. J., additional, Wong, K. T., additional, El Mellah, I., additional, Bolte, J., additional, Herpin, F., additional, Richards, A. M. S., additional, Baudry, A., additional, Etoka, S., additional, Gray, M. D., additional, Millar, T. J., additional, Menten, K. M., additional, Müller, H. S. P., additional, Plane, J. M. C., additional, Yates, J., additional, and Zijlstra, A., additional
- Published
- 2023
- Full Text
- View/download PDF
26. ALMA High-frequency Long Baseline Campaign in 2021 : Highest Angular Resolution Submillimeter Wave Images for the Carbon-rich Star R Lep
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Asaki, Yoshiharu, Maud, Luke T., Francke, Harold, Nagai, Hiroshi, Petry, Dirk, Fomalont, Edward B., Humphreys, Elizabeth, Richards, Anita M. S., Wong, K. T., Dent, William, Hirota, Akihiko, Fernandez, Jose Miguel, Takahashi, Satoko, Hales, Antonio S., Asaki, Yoshiharu, Maud, Luke T., Francke, Harold, Nagai, Hiroshi, Petry, Dirk, Fomalont, Edward B., Humphreys, Elizabeth, Richards, Anita M. S., Wong, K. T., Dent, William, Hirota, Akihiko, Fernandez, Jose Miguel, Takahashi, Satoko, and Hales, Antonio S.
- Abstract
The Atacama Large Millimeter/submillimeter Array (ALMA) was used in 2021 to image the carbon-rich evolved star R Lep in Bands 8-10 (397-908 GHz) with baselines up to 16 km. The goal was to validate the calibration, using band-to-band (B2B) phase referencing with a close phase calibrator J0504-1512, 1.degrees 2 from R Lep in this case, and the imaging procedures required to obtain the maximum angular resolution achievable with ALMA. Images of the continuum emission and the hydrogen cyanide (HCN) maser line at 890.8 GHz, from the J = 10-9 transition between the (1110) and (0400) vibrationally excited states, achieved angular resolutions of 13, 6, and 5 mas in Bands 8-10, respectively. Self-calibration (self-cal) was used to produce ideal images to compare with the B2B phase referencing technique. The continuum emission was resolved in Bands 9 and 10, leaving too little flux for the self-cal of the longest baselines, so these comparisons are made at coarser resolution. Comparisons showed that B2B phase referencing provided phase corrections sufficient to recover 92%, 83%, and 77% of the ideal image continuum flux densities. The HCN maser was sufficiently compact to obtain self-cal solutions in Band 10 for all baselines (up to 16 km). In Band 10, B2B phase referencing as compared to the ideal images recovered 61% and 70% of the flux density for the HCN maser and continuum, respectively.
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- 2023
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27. Clinical and Pathological Manifestations of Human Henipavirus Infection
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Wong, K. T., Tan, C. T., Lee, Benhur, editor, and Rota, Paul A., editor
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- 2012
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28. Ultrasound Investigations in Head and Neck Cancer Patients
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Lee, Yolanda Y. P., Wong, K. T., King, Ann D., Ahuja, Anil T., and Bernier, Jacques, editor
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- 2011
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29. An analysis of inter-professional collaboration in osteoporosis screening at a primary care level using the DʼAmour model
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Toh, L. S., Lai, P. S.M., Othman, S., Wong, K. T., Low, B. Y., and Anderson, C.
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- 2017
- Full Text
- View/download PDF
30. Four-Dimensional Computed Tomography for Localisation of Parathyroid Adenomas.
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Leung, H. S., Liu, S. Y. W., Wong, K. T., Yu, S. M., and King, A. D.
- Published
- 2023
- Full Text
- View/download PDF
31. High Morbidity and Mortality in Adults Hospitalized for Respiratory Syncytial Virus Infections
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Lee, N., Lui, G. C. Y., Wong, K. T., Li, T. C. M., Tse, E. C. M., Chan, J. Y. C., Yu, J., Wong, S. S. M., Choi, K. W., Wong, R. Y. K., Ngai, K. L. K., Hui, D. S. C., and Chan, P. K. S.
- Published
- 2013
- Full Text
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32. Molecules, shocks, and disk in the axi-symmetric wind of the MS-type AGB star RS Cancri
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Winters, J. M., Hoai, D. T., Wong, K. T., Kim, W-J, Nhung, P. T., Tuan-Anh, P., Lesaffre, P., Darriulat, P., Le Bertre, T., Winters, J. M., Hoai, D. T., Wong, K. T., Kim, W-J, Nhung, P. T., Tuan-Anh, P., Lesaffre, P., Darriulat, P., and Le Bertre, T.
- Abstract
Context. The latest evolutionary phases of low- and intermediate-mass stars are characterized by complex physical processes like turbulence, convection, stellar pulsations, magnetic fields, condensation of solid particles, and the formation of massive outflows that inject freshly produced heavy elements and dust particles into the interstellar medium. Aims. By investigating individual objects in detail, we wish to analyze and disentangle the effects of the interrelated physical processes on the structure of the wind-forming regions around them. Methods. We use the Northern Extended Millimeter Array to obtain spatially and spectrally resolved observations of the semi-regular asymptotic giant branch (AGB) star RS Cancri and apply detailed 3D reconstruction modeling and local thermodynamic equilibrium radiative transfer calculations in order to shed light on the morpho-kinematic structure of its inner, wind-forming environment. Results. We detect 32 lines of 13 molecules and isotopologs (CO, SiO, SO, SO2, H2O, HCN, PN), including several transitions from vibrationally excited states. HCN, H (CN)-C-13, and millimeter vibrationally excited H2O, SO, (SO)-S-34, SO2, and PN are detected for the first time in RS Cnc. Evidence for rotation is seen in HCN, SO, SO2, and SiO(v = 1). From CO and SiO channel maps, we find an inner, equatorial density enhancement, and a bipolar outflow structure with a mass-loss rate of 1 x 10(-7) M-circle dot yr(-1) for the equatorial region and of 2 x 10(-2) M-circle dot yr(-1) for the polar outflows. The (CO)-C-12/(CO)-C-13 ratio is measured to be similar to 20 on average, 24 +/- 2 in the polar outflows and 19 +/- 3 in the equatorial region. We do not find direct evidence of a companion that might explain this kind of kinematic structure, and explore the possibility that a magnetic field might be the cause of it. The innermost molecular gas is influenced by stellar pulsation and possibly by convective cells that leave their imprint on broad wing
- Published
- 2022
33. ATOMIUM: ALMA tracing the origins of molecules in dust forming oxygen rich M-type stars
- Author
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Gottlieb, C. A., primary, Decin, L., additional, Richards, A. M. S., additional, De Ceuster, F., additional, Homan, W., additional, Wallström, S. H. J., additional, Danilovich, T., additional, Millar, T. J., additional, Montargès, M., additional, Wong, K. T., additional, McDonald, I., additional, Baudry, A., additional, Bolte, J., additional, Cannon, E., additional, De Beck, E., additional, de Koter, A., additional, El Mellah, I., additional, Etoka, S., additional, Gobrecht, D., additional, Gray, M., additional, Herpin, F., additional, Jeste, M., additional, Kervella, P., additional, Khouri, T., additional, Lagadec, E., additional, Maes, S., additional, Malfait, J., additional, Menten, K. M., additional, Müller, H. S. P., additional, Pimpanuwat, B., additional, Plane, J. M. C., additional, Sahai, R., additional, Van de Sande, M., additional, Waters, L. B. F. M., additional, Yates, J., additional, and Zijlstra, A., additional
- Published
- 2022
- Full Text
- View/download PDF
34. Molecules, shocks, and disk in the axi-symmetric wind of the MS-type AGB star RS Cancri
- Author
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Winters, J. M., primary, Hoai, D. T., additional, Wong, K. T., additional, Kim, W.-J., additional, Nhung, P. T., additional, Tuan-Anh, P., additional, Lesaffre, P., additional, Darriulat, P., additional, and Le Bertre, T., additional
- Published
- 2022
- Full Text
- View/download PDF
35. ATOMIUM: halide molecules around the S-type AGB star W Aquilae
- Author
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Danilovich, T., primary, Van de Sande, M., additional, Plane, J. M. C., additional, Millar, T. J., additional, Royer, P., additional, Amor, M. A., additional, Hammami, K., additional, Decock, L., additional, Gottlieb, C. A., additional, Decin, L., additional, Richards, A. M. S., additional, De Beck, E., additional, Baudry, A., additional, Bolte, J., additional, Cannon, E., additional, De Ceuster, F., additional, de Koter, A., additional, Etoka, S., additional, Gobrecht, D., additional, Gray, M., additional, Herpin, F., additional, Homan, W., additional, Jeste, M., additional, Kervella, P., additional, Khouri, T., additional, Lagadec, E., additional, Maes, S., additional, Malfait, J., additional, McDonald, I., additional, Menten, K. M., additional, Montargès, M., additional, Müller, H. S. P., additional, Pimpanuwat, B., additional, Sahai, R., additional, Wallström, S. H. J., additional, Waters, L. B. F. M., additional, Wong, K. T., additional, Yates, J., additional, and Zijlstra, A., additional
- Published
- 2021
- Full Text
- View/download PDF
36. ATOMIUM:Halide molecules around the S-type AGB star W Aquilae
- Author
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Danilovich, T., Sande, M. Van de, Plane, J. M. C., Millar, T. J., Royer, P., Amor, M. A., Hammami, K., Decock, L., Gottlieb, C. A., Decin, L., Richards, A. M. S., Beck, E. De, Baudry, A., Bolte, J., Cannon, E., Ceuster, F. De, Koter, A. de, Etoka, S., Gobrecht, D., Gray, M., Herpin, F., Homan, W., Jeste, M., Kervella, P., Khouri, T., Lagadec, E., Maes, S., Malfait, J., McDonald, I., Menten, K. M., Montargès, M., Müller, H. S. P., Pimpanuwat, B., Sahai, R., Wallström, S. H. J., Waters, L. B. F. M., Wong, K. T., Yates, J., and Zijlstra, A.
- Subjects
astro-ph.SR ,astro-ph.GA - Abstract
S-type asymptotic giant branch (AGB) stars are thought to be intermediates in the evolution of oxygen- to carbon-rich AGB stars. The chemical compositions of their circumstellar envelopes are also intermediate, but have not been studied in as much detail as their carbon- and oxygen-rich counterparts. We aim to determine the abundances of AlCl and AlF from rotational lines, which have been observed for the first time towards an S-type AGB star, W Aql. In combination with models based on PACS observations, we aim to update our chemical kinetics network based on these results. We analyse ALMA observations towards W Aql of AlCl in the ground and first two vibrationally excited states and AlF in the ground vibrational state. Using radiative transfer models, we determine the abundances and spatial abundance distributions of Al$^{35}$Cl, Al$^{37}$Cl, and AlF. We also model HCl and HF emission and compare these models to PACS spectra to constrain the abundances of these species. AlCl is found in clumps very close to the star, with emission confined within 0.1$^{\prime\prime}$ of the star. AlF emission is more extended, with faint emission extending 0.2$^{\prime\prime}$ to 0.6$^{\prime\prime}$ from the continuum peak. We find peak abundances, relative to H$_2$, of $1.7\times 10^{-7}$ for Al$^{35}$Cl, $7\times 10^{-8}$ for Al$^{37}$Cl and $1\times 10^{-7}$ for AlF. From the PACS spectra, we find abundances of $9.7\times 10^{-8}$ and $\leq 10^{-8}$, relative to H$_2$, for HCl and HF, respectively. The AlF abundance exceeds the solar F abundance, indicating that fluorine synthesised in the AGB star has already been dredged up to the surface of the star and ejected into the circumstellar envelope. From our analysis of chemical reactions in the wind, we conclude that AlF may participate in the dust formation process, but we cannot fully explain the rapid depletion of AlCl seen in the wind.
- Published
- 2021
37. Viral neuronotropism is important in the pathogenesis of Murray Valley encephalitis
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Fu, T. L., Ong, K. C., Tran, Y. D., McLean, C. A., and Wong, K. T.
- Published
- 2016
- Full Text
- View/download PDF
38. Ultrastructure of the Human Skeletal Muscle Sarcocyst
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Wong, K. T. and Pathmanathan, R.
- Published
- 1994
- Full Text
- View/download PDF
39. A randomized study to investigate the effect of focal zone size on treatment outcomes in patients undergoing extracorporeal shockwave lithotripsy to renal calculi
- Author
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Ng, C.F.A., primary, Yee, C-H., additional, Kong, W.Y., additional, Lau, S.Y., additional, Chiu, K.F., additional, Teoh, Y.C., additional, Chu, C.W., additional, and Wong, K-T., additional
- Published
- 2021
- Full Text
- View/download PDF
40. Use of end-cutting needles in ultrasound-guided biopsy of neck lesions
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Yuen, H. Y., Lee, Y., Bhatia, K., Wong, K. T., and Ahuja, A. T.
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- 2012
- Full Text
- View/download PDF
41. Social Stigma Affecting Non-adherence of Insulin Therapy for Type 2 Diabetes Management in Malaysia
- Author
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Chai, J., Anderson, C., Wong, K. T., and Hussein, Z.
- Published
- 2014
- Full Text
- View/download PDF
42. Interprofessional Collaboration - Can Malaysian Pharmacists Expand their Non-dispensing Role in Osteoporosis Screening and Prevention?
- Author
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Toh, L. S., Lai, P. S.M., Wong, K. T., Low, B. Y., and Anderson, C.
- Published
- 2014
- Full Text
- View/download PDF
43. Viral morphogenesis and morphological changes in human neuronal cells following Tioman and Menangle virus infection
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Yaiw, K. C., Hyatt, A., VanDriel, R., Crameri, S. G., Eaton, B., Wong, M. H., Wang, L. F., Ng, M. L., Bingham, J., Shamala, D., and Wong, K. T.
- Published
- 2008
- Full Text
- View/download PDF
44. Frequency and determinants of prestroke dementia in a Chinese cohort
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Tang, Wai Kwong, Chan, Sandra S. M., Chiu, Helen F. K., Ungvari, Gabor S., Wong, Ka Sing, Kwok, Timothy C. Y., Mok, Vincent, Wong, K. T., Richards, Polly S., and Ahuja, A. T.
- Published
- 2004
- Full Text
- View/download PDF
45. Unusual parotid gland lesions: A pictorial review
- Author
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Cho, C. M., Tong, S. L., Bhatia, K. S., Wong, K. T., Yuen, H. Y., Lee, Y. P., and Ahuja, A. T.
- Published
- 2013
- Full Text
- View/download PDF
46. Nipah virus infection, an emerging paramyxoviral zoonosis
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Wong, K. T., Shieh, W. J., Zaki, S. R., and Tan, C. T.
- Published
- 2002
- Full Text
- View/download PDF
47. A Prospective, Randomized Study of the Clinical Effects of Shock Wave Delivery for Unilateral Kidney Stones: 60 Versus 120 Shocks per Minute
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Ng, Chi-Fai, Lo, Anthony K.Y., Lee, Kim W.M., Wong, K. T., Chung, Wai-yee, and Gohel, Danny
- Published
- 2012
- Full Text
- View/download PDF
48. Enterovirus 71 encephalomyelitis and Japanese encephalitis can be distinguished by topographic distribution of inflammation and specific intraneuronal detection of viral antigen and RNA
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Wong, K. T., Ng, K. Y., Ong, K. C., Ng, W. F., Shankar, S. K., Mahadevan, A., Radotra, B., Su, I. J., Lau, G., Ling, A. E., Chan, K. P., Macorelles, P., Vallet, S., Cardosa, M. J., Desai, A., Ravi, V., Nagata, N., Shimizu, H., and Takasaki, T.
- Published
- 2012
- Full Text
- View/download PDF
49. (Sub)stellar companions shape the winds of evolved stars
- Author
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Decin, L., primary, Montargès, M., additional, Richards, A. M. S., additional, Gottlieb, C. A., additional, Homan, W., additional, McDonald, I., additional, El Mellah, I., additional, Danilovich, T., additional, Wallström, S. H. J., additional, Zijlstra, A., additional, Baudry, A., additional, Bolte, J., additional, Cannon, E., additional, De Beck, E., additional, De Ceuster, F., additional, de Koter, A., additional, De Ridder, J., additional, Etoka, S., additional, Gobrecht, D., additional, Gray, M., additional, Herpin, F., additional, Jeste, M., additional, Lagadec, E., additional, Kervella, P., additional, Khouri, T., additional, Menten, K., additional, Millar, T. J., additional, Müller, H. S. P., additional, Plane, J. M. C., additional, Sahai, R., additional, Sana, H., additional, Van de Sande, M., additional, Waters, L. B. F. M., additional, Wong, K. T., additional, and Yates, J., additional
- Published
- 2020
- Full Text
- View/download PDF
50. Bio-sorptive Removal of Methyl Orange by Micro-Grooved Chitosan (GCS) Beads: Optimization of Process Variables Using Taguchi L9 Orthogonal Array
- Author
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Wong, K. T., primary, Wong, V. L., additional, and Lim, S. S., additional
- Published
- 2020
- Full Text
- View/download PDF
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