Publications

PEER-REVIEWED JOURNAL ARTICLES

1. R. Dahale, et al., (including J. Y. Koay), ‘Origin of the Ring Ellipticity in the Black Hole Images of M87*’, Astronomy & Astrophysics 699,  A279 (2025).

2. C. Goddi, et al., (including J. Y. Koay), ‘First polarization study of the M87 jet and active galactic nuclei at submillimeter wavelengths with ALMA’, Astronomy & Astrophysics 699,  A265 (2025).

3. D. Lawther,  M. Vestergaard, S. Raimundo, X. Fan, J. Y. Koay, 'Flares in the Changing Look AGN Mrk 590. II: Deep X-ray observations reveal a Comptonizing inner accretion flow', Monthly Notices of the Royal Astronomical Society 539, 509 (2025).

4. The EHT collaboration, et al., (including J. Y. Koay), ‘The persistent shadow of the supermassive black hole of M87. II. Model comparisons and theoretical interpretations’, Astronomy & Astrophysics 693, A265 (2025).

5. A. K. Baczko, et al., (including J. Y. Koay), ‘The putative center in NGC 1052’,  Astronomy & Astrophysics 692, 205 (2024).

6. J. C. Algaba, et al., (including J. Y. Koay), ‘Broadband multi-wavelength properties of M87 during the 2018 EHT campaign including a very high energy flaring episode’,  Astronomy & Astrophysics 692, 140 (2024).

7. The EHT collaboration, et al., (including J. Y. Koay), ‘First Very Long Baseline Interferometry Detections at 870 μm’, The Astronomical Journal 168, 130 (2024).

8. The EHT collaboration, et al., (including J. Y. Koay), ‘First Sagittarius A* Event Horizon Telescope Results. VIII. Physical Interpretation of the Polarized Ring’, The Astrophysical Journal Letters 964, L26 (2024).

9. The EHT collaboration, et al., (including J. Y. Koay), ‘First Sagittarius A* Event Horizon Telescope Results. VII. Polarization of the Ring’, The Astrophysical Journal Letters 964, L25 (2024).

10. G. F. Paraschos, et al., (including J. Y. Koay), ‘Ordered magnetic fields around the 3C 84 central black hole’, Astronomy & Astrophysics 682, L3 (2024).

11. The EHT collaboration, et al., (including J. Y. Koay), ‘The persistent shadow of the supermassive black hole of M87. I. Observations, calibration, imaging, and analysis’, Astronomy & Astrophysics 681, A79 (2024).

12. P.  Torne, et. al. (including J. Y. Koay), ‘A Search for Pulsars around Sgr A* in the First Event Horizon Telescope Data Set’, The Astrophysical Journal 959, 14 (2023).

13. P.-C. Hsu, J. Y. Koay, S. Matsushita, C.-Y. Hwang, T. Hovatta, S. Kiehlmann, A. Readhead, W. Max-Moerbeck, R. Reeves, ‘Milliarcsecond core size dependence of the radio variability of blazars’, Monthly Notices of the Royal Astronomical Society 525, 5105 (2023).

14. F. Roelofs, et. al. (including J. Y. Koay), ‘Polarimetric Geometric Modeling for mm-VLBI Observations of Black Holes’, The Astrophysical Journal 957, 29 (2023).

15. The EHT collaboration, et al., (including J. Y. Koay), ‘First M87 Event Horizon Telescope Results. IX. Detection of Near-horizon Circular Polarization’, The Astrophysical Journal Letters, 957, 42 (2023).

16. B. Prather, et. al. (including J. Y. Koay), ‘Comparison of Polarized Radiative Transfer Codes Used by the EHT Collaboration’, The Astrophysical Journal 950, 35 (2023).

17. R. Lu, et al. (including J. Y. Koay), ‘A ring-like accretion structure in M87 connecting its black hole and jet’, Nature, 616, 686 (2023).

18. D. Lawther, M. Vestergaard, S. Raimundo, J. Y. Koay, B. M. Peterson, X. Fan, D. Grupe, S. Mathur, ‘Flares in the changing look AGN Mrk 590. I: The UV response to X-ray outbursts suggests a more complex re- processing geometry than a standard disk’, Monthly Notices of the Royal Astronomical Society, 519, 3903 (2023).

19. S. Jorstad, et al., (including J. Y. Koay), ‘The Event Horizon Telescope Image of the Quasar NRAO 530’, The Astrophysical Journal 943, 170 (2023).

20. A. Broderick, et al., (including J. Y. Koay), ‘The Photon Ring in M87*’, The Astrophysical Journal, 935, 61 (2022).

21. S. Issaoun, et al., (including J. Y. Koay), ‘Resolving the inner parsec of the blazar J1924–2914 with the Event Horizon Telescope’, The Astrophysical Journal, 934, 145 (2022).

22. G.-Y. Zhao, et al., (including J. Y. Koay), ‘Unravelling the Innermost Jet Structure of OJ 287 with the First GMVA+ALMA Observations’, The Astrophysical Journal, 932, 72 (2022).

23. A. Broderick, et al., (including J. Y. Koay), ‘Characterizing and Mitigating Intraday Variability: Reconstructing source structure in accreting black holes with mm-VLBI’, The Astrophysical Journal Letters, 930 L21 (2022).

24. B. Georgiev, et al., (including J. Y. Koay), ‘A universal power law prescription for variability from synthetic images of black hole accretion flows’, The Astrophysical Journal Letters, 930 L20 (2022).

25. M. Wielgus, et al., (including J. Y. Koay), ‘Millimeter light curves of Sagittarius A* observed during the 2017 Event Horizon Telescope campaign’, The Astrophysical Journal Letters, 930 L19 (2022)

26. J. Farah et al., (including J. Y. Koay),‘Selective dynamical imaging of interferometric data’,The Astrophysical Journal Letters, 930 L18 (2022).

27. The EHT collaboration, et al., (including J. Y. Koay), ‘First Sgr A* Event Horizon Telescope Results VI: Testing the Black Hole Metric’, The Astrophysical Journal Letters, 930 L17 (2022).

28. The EHT collaboration, et al., (including J. Y. Koay), ‘First Sgr A* Event Horizon Telescope Results. V. Testing Astrophysical Models of the Galactic Center Black Hole’, The Astrophysical Journal Letters, 930 L16 (2022).

29. The EHT collaboration, et al., (including J. Y. Koay), ‘First Sgr A* Event Horizon Telescope Results. IV. Variability, Morphology, and Black Hole Mass’, The Astrophysical Journal Letters, 930 L15 (2022).

30. The EHTcollaboration,etal.,(including J. Y. Koay),‘First Sagittarius A* Event Horizon Telescope Results. III. Imaging of the Galactic Center Supermassive Black Hole’, The Astrophysical Journal Letters, 930 L14 (2022).

31. The EHT collaboration, et al., (including J. Y. Koay), ‘First Sgr A* Event Horizon Telescope Results II: EHT and Multi-wavelength Observations, Data Processing and Calibration’, The Astrophysical Journal Letters, 930 L13 (2022).

32. The EHT collaboration, et al., (including J. Y. Koay), ‘First Sgr A* Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole in the Center of the Milky Way’, The Astrophysical Journal Letters, 930 L12 (2022).

33. K. Satapathy, et al. (including J. Y. Koay), ‘The variability of the black-hole image in M87 at the dynamical time scale’, The Astrophysical Journal, 925, 13, (2022).

34. M. Janssen, et al. (including J. Y. Koay), ‘Event Horizon Telescope observations of the jet launching and collimation in Centaurus A’, Nature Astronomy, 5, 1017, (2021).

35. P. Kocherlakota, et al. (including J. Y. Koay), ‘Constraints on black-hole charges with the 2017 EHT obser- vations of M87*’, Physical Review D, 103, 104047 (2021).

36. R. Narayan, et al., (including J. Y. Koay), ‘The Polarized Image of a Synchrotron Emitting Ring of Gas Orbiting a Black Hole’, The Astrophysical Journal, 912, 35 (2021).

37. W.-P. Lo, K. Asada, S. Matsushita, M. Nakamura, H.-Y. Pu, C. Tseng, K. Akiyama, J. C. Algaba, G. C. Bower, R. Rao, J. Y. Koay, P. M. Koch, S. Koyama, P. T. P. Ho, M. Inoue, ‘Constraints on the Mass Accretion Rate onto the Supermassive Black Hole of Cygnus A Using the Submillimeter Array’, The Astrophysical Journal, 911, 35 (2021).

38. EHT MWL Science Working Group, et al., (including J. Y. Koay), ‘Broadband Multi-wavelength Properties of M87 During the 2017 Event Horizon Telescope Campaign’, The Astrophysical Journal Letters, 911, L11 (2021).

39. C. Goddi, et al., (including J. Y. Koay), ‘Polarimetric properties of Event Horizon Telescope targets from ALMA’, The Astrophysical Journal Letters, 910, L14 (2021).

40. The EHT collaboration (including J. Y. Koay), ‘First M87 Event Horizon Telescope Results. VIII. Magnetic Field Structure near The Event Horizon’, The Astrophysical Journal Letters, 910, L13 (2021).

41. The EHT collaboration (including J. Y. Koay), ‘First M87 Event Horizon Telescope Results. VII. Polarization of the Ring’, The Astrophysical Journal Letters, 910, L12 (2021).

42. J. Yang, I. van Bemmel, Z. Paragi, S. Komossa, F.Yuan, X. Yang, T. An, J. Y. Koay, C. Reynolds, J. B. R. Oonk, X. Liu, Q. Wu, ‘A parsec-scale faint jet in the nearby changing-look Seyfert galaxy Mrk 590’, Monthly Notices of the Royal Astronomical Society, 502, L61 (2021).

43. D. Psaltis, et al. (including J. Y. Koay), ‘Gravitational Test Beyond the First Post-Newtonian Order with the Shadow of the M87 Black Hole’, Physical Review Letters, 125, 141104 (2020).

44. M. Wielgus, et al. (including J. Y. Koay), ‘Monitoring the Morphology of M87* in 2009-2017 with the Event Horizon Telescope’, The Astrophysical Journal, 901, 67 (2020).

45. J. Y. Kim, et al., (including J. Y. Koay), ‘Event Horizon Telescope imaging of the archetypal blazar 3C 279 at an extreme 20 microarcsecond resolution’, Astronomy & Astrophysics, 640, 69, (2020).

46. R. Gold., et al. (including J. Y. Koay), ‘Verification of Radiative Transfer Schemes for the EHT’, The Astrophysical Journal, 897, 148 (2020).

47. A. E. Broderick., et al. (including J. Y. Koay), ‘THEMIS: A Parameter Estimation Framework for the Event Horizon Telescope’, The Astrophysical Journal, 897, 139 (2020).

48. F. Roelofs, et al. (including J. Y. Koay), ‘SYMBA: An end-to-end VLBI synthetic data generation pipeline’, Astronomy & Astrophysics, 636, A5 (2020).

49. Y. Y. Kovalev, et al. (including J. Y. Koay), ‘Detection statistics of the RadioAstron AGN survey’,  Advances in Space Research, 65, 705 (2020).

50. D. L. Jauncey, J. Y. Koay, et al., ‘Interstellar Scintillation, ISS, and Intrinsic Variability of Radio AGN’,  Advances in Space Research, 65, 756 (2020).

51. J. Y. Koay, D. L. Jauncey, T. Hovatta, S. Kiehlmann, H. E. Bignall, W. Max-Moerbeck, T. J. Pearson, A. C. S. Readhead, R. Reeves, C. Reynolds, H. Vedantham, ‘The presence of interstellar scintillation in the 15 GHz interday variability of 1158 OVRO-monitored blazars’, Monthly Notices of the Royal Astronomical Society, 489, 4365 (2019).

52. O. Porth, et al. (including J. Y. Koay), ‘The Event Horizon General Relativistic Magnetohydrodynamic Code Comparison Project’, The Astrophysical Journal Supplement Series, 243, 26 (2019)

53. S. Raimundo, M. Vestergaard, J. Y. Koay, D. Lawther,  V. Casasola, B. M. Peterson, ‘MUSE observations of a changing-look AGN I: The re-appearance of the broad emission lines’, Monthly Notices of the Royal Astronomical Society, 486, 123 (2019).

54. The EHT collaboration (including J. Y. Koay), ‘First M87 Event Horizon Telescope Results. VI. the Shadow and Mass of the Central Black Hole’, The Astrophysical Journal Letters, 875, L6 (2019).

55. The EHT collaboration (including J. Y. Koay), ‘First M87 Event Horizon Telescope Results. V. Physical Origin of the Asymmetric Ring’, The Astrophysical Journal Letters, 875, L5 (2019).

56. The EHT collaboration (including J. Y. Koay), ‘First M87 Event Horizon Telescope Results. IV. Imaging the Central Supermassive Black Hole’, The Astrophysical Journal Letters, 875, L4 (2019).

57. The EHT collaboration (including J. Y. Koay), ‘First M87 Event Horizon Telescope Results. III. Data Pro- cessing and Calibration’, The Astrophysical Journal Letters, 875, L3 (2019).

58. The EHT collaboration (including J. Y. Koay), ‘First M87 Event Horizon Telescope Results. II. Array and Instrumentation’, The Astrophysical Journal Letters, 875, L2 (2019).

59. The EHT collaboration (including J. Y. Koay), ‘First M87 Event Horizon Telescope Results. I. the Shadow of the Supermassive Black Hole’, The Astrophysical Journal Letters, 875, L1 (2019).

60. J. Y. Koay, J.-P. Macquart, D. L. Jauncey, T. Pursimo, M. Giroletti, H. E. Bignall, J. E. J. Lovell, B. J. Rick- ett, L. Kedziora-Chudczer, R. Ojha, C. Reynolds, ‘The MASIV Survey - IV. Relationship between intra-day scintillation and intrinsic variability of radio AGNs’, Monthly Notices of the Royal Astronomical Society, 474, 4396 (2018).

61. D. L. Jauncey, H. E. Bignall, L. Kedziora-Chudczer, J. Y. Koay, J. E. J. Lovell, J.-P. Macquart, R. Ojha, T. Pursimo, C. Reynolds, B. J. Rickett ‘Interstellar Scintillation and Scattering of Micro-arcsecond AGN’, Galaxies, 4, 62 (2016).

62. J. Y. Koay, M. Vestergaard, H. E. Bignall, C. Reynolds, B. M. Peterson, ‘Parsec-scale radio morphology and variability of a changing-look AGN: the case of Mrk 590’, Monthly Notices of the Royal Astronomical Society, 460, 304 (2016).

63. J. Y. Koay, M. Vestergaard, V. Casasola, D. Lawther, & B. M. Peterson, ‘ALMA Probes the Molecular Gas Reservoirs in the Changing-Look Seyfert Galaxy Mrk 590’, Monthly Notices of the Royal Astronomical Society, 455, 2745 (2016).

64. K. C. Teng, J. Y. Koay, S. H. Tey, K. S. Lim, H. T. Ewe, & H. T. Chuah, ‘A Dense Medium Microwave Backscattering Model for the Remote Sensing of Oil Palm’, IEEE Transactions on Geoscience and Remote Sensing, 53, 3250 (2015).

65. J. Y. Koay & J.-P. Macquart, ‘Scatter Broadening of Compact Radio Sources by the Ionized Intergalactic Medium: Prospects for Detection with Space VLBI and the Square Kilometre Array’, Monthly Notices of the Royal Astronomical Society, 446, 2370 (2015).

66. J.-P. Macquart & J. Y. Koay, ‘Temporal Smearing of Transient Radio Sources by the Intergalactic Medium,’ The Astrophysical Journal, 776, 125 (2013).

67. T. Pursimo, R. Ojha, D. L. Jauncey, B. J. Rickett, M. S. Dutka, J. Y. Koay, J. E. J. Lovell, H. E. Bignall, L. Kedziora-Chudczer, & J.-P. Macquart, ‘The Micro-Arcsecond Scintillation-Induced Variability (MASIV) Survey III. Optical Identifications and New Redshifts,’ The Astrophysical Journal, 767, 14 (2013).

68. J. Y. Koay, J.-P. Macquart, B. J. Rickett, H. E. Bignall, D. L. Jauncey, T. Pursimo, C. Reynolds, J. E. J. Lovell, L. Kedziora-Chudczer, & R. Ojha, ‘Why Do Compact Active Galactic Nuclei at High Redshift Scintillate Less?,’ The Astrophysical Journal, 756, 29 (2012).

69. J. Y. Koay, H.E.Bignall, J.-P. Macquart, D.L. Jauncey, B.J. Rickett,& J.E.J. Lovell,‘Detection of Six Rapidly Scintillating Active Galactic Nuclei and the Diminished Variability of J1819+3845,’ Astronomy & Astrophysics, 534, L1 (2011).

70. J. Y. Koay, J.-P. Macquart, B. J. Rickett, H. E. Bignall, J. E. J. Lovell, C. Reynolds, D. L. Jauncey, T. Pursimo, L. Kedziora-Chudczer, & R. Ojha, ‘Dual-frequency Observations of 140 Compact, Flat-spectrum Active Galactic Nuclei for Scintillation-induced Variability,’ The Astronomical Journal, 142, 108, (2011).

71. J.-P. Macquart, et al. (including J. Y. Koay), ‘The Commensal Real-Time ASKAP Fast Transients (CRAFT) Survey,’ Publications of the Astronomical Society of Australia, 27, 272, (2010).

72. K. S. Lim, J. Y. Koay, V. C. Koo, H. T. Ewe, & W. L. Kung, ‘High Angular Resolution Measurements of the Monostatic Backscattering Coefficient of Rice Fields,’ Journal of Electromagnetic Waves and Applications, 23, 1, (2009).

73. J. Y. Koay, H. T. Ewe, & H. T. Chuah, ‘A Study of Fresnel Scattered Fields for Ellipsoidal and Elliptic-disk- shaped Scatterers,’ IEEE Transactions on Geoscience and Remote Sensing, 46, 1091, (2008).

74. J. Y. Koay, C. P. Tan, K. S. Lim, Saiful Bahari, H. T. Ewe, H. T. Chuah, & J. A. Kong, ‘Paddy Fields as Electrically Dense Media: Theoretical Modeling and Measurement Comparisons,’ IEEE Transactions on Geoscience and Remote Sensing, 45, 2837, (2007).

75. C. P. Tan, J. Y. Koay, K. S. Lim, H. T. Teng, H. T. Ewe, H. T. Chuah, & S. Bahari, ‘Image Classification of Rice Growth Stages using Combination of Entropy Decomposition and Support Vector Machine (EDSVM),’ Asian Journal of Geoinformatics, 7, 5, (2007).

76. C. P. Tan, J. Y. Koay, K. S. Lim, H. T. Ewe, & H. T. Chuah, ‘Classification of Multi-Temporal SAR Images For Rice Crops Using Combined Entropy Decomposition and Support Vector Machine Technique,’ Progress in Electromagnetics Research, 71, 19, (2007).

77. C. P. Tan, J. Y. Koay, H. T. Ewe, H. T. Chuah, & S. Bahari, ‘Applications of Remote Sensing in the Monitoring of Rice Crops,’ Journal of the Institution of Engineers Malaysia, 67, 2, (2006).

INVITED JOURNAL ARTICLES

1. Z. Z. Abidin, M. F.  Asillam, & J. Y. Koay, ‘Expanding Astronomy Research in Malaysia’, Nature Astronomy, (2020).

TECHNICAL MEMOS

1. J. Y. Koay, et al., ‘Absolute Flux Density Calibration of the Greenland Telescope Data for Event Horizon Telescope Observations’, EHT Memo Series, 2023-L1-02 (2023).

2. J. Y. Koay, et al.,‘Metadata for the Flux Density Calibration of the April 2018 Event Horizon Telescope Data’, EHT Memo Series, 2023-L1-01 (2023).

3. M. Wielgus, L. Blackburn, S. Issaoun, M. Janssen, M. D. Johnson, J. Y. Koay, ‘EHT data set validation and characterization of errors’, EHT Memo Series, 2019-CE-02 (2019).

BOOK CHAPTERS

1. J. Y. Koay,  Y. J. Lee, H. T. Ewe, & H. T. Chuah, ‘Electromagnetic Wave Scattering in Dense Media: Applications in the Remote Sensing of Sea Ice and Vegetation’, Electromagnetic Scattering: a Remote Sensing Perspective, World Scientific Publishing (2017).

2. H. E. Bignall, S. Croft, T. Hovatta, J. Y. Koay, J. Lazio, J.-P. Macquart, & C. Reynolds, ‘Time Domain Studies of Active Galactic Nuclei: intrinsic variability and propagation effects’,  Advancing Astrophysics with the Square Kilometre Array, PoS(AASKA14)058 (2015).

CONFERENCE PROCEEDINGS

1. N. A. Patel et al. (including J. Y. Koay), ‘Advanced metrology sensor applications for improved pointing performance of the Greenland Telescope’, Proceedings of the Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 13094, 130940G (2024).

2. M. T. Chen et al. (including J. Y. Koay), ‘The Greenland Telescope: Thule Operations’, Proceedings of the 2023 XXXVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS), 2642-4339, 232, (2023).

3. L. C. W. Huang et al. (including J. Y. Koay), ‘Control and monitoring software for the Greenland Telescope’, Proceedings of the Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11452, 114521S (2020).

4. J. Y. Koay et al.,‘Status of scientific commissioning of the Greenland Telescope’, Proceedings of the Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 11445, 114450Q (2020).

5. H. Nishioka et al. (including J. Y. Koay), ‘Control and Monitoring System for the Greenland Telescope: Computers, Network and Software’, Proceedings of the Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 10700, 107005N (2018).

6. S. Matsushita et al. (including J. Y. Koay), ‘Commissioning Status of the Greenland Telescope’, Proceedings of the Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 10700, 1070029 (2018).

7. M.-T. Chen et al. (including J. Y. Koay), ‘The Greenland Telescope: Thule Operations’, Proceedings of the Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 10700, 107000H (2018).

8. J. Y. Koay, M. Vestergaard, V. Casasola, & B. M. Peterson, ‘Circumnuclear Molecular Gas Reservoirs in Mrk 590, a Seyfert Galaxy in Transition’, Proceedings of Revolution in Astronomy with ALMA - the Third Year, Astronomical Society of the Pacific Conference Series, 499, 163 (2015).

9. K. C. Teng, J. Y. Koay, S. H. Tey, H. T. Ewe, & H. T. Chuah, ‘Monitoring of Oil Palm Plantations and Growth Variations with a Dense Vegetation Model,’ Proceedings of the International Geoscience and Remote Sensing Symposium, Quebec, Canada, (2014).

10. T. Pursimo, R. Ojha, D. L. Jauncey, J. E. J. Lovell, M. Dutka, H. E. Bignall, J.-P. Macquart, B. J., Rickett, L. Kedziora-Chudczer, & J. Y. Koay, ‘The MASIV Survey: Spectroscopic Identifications of Compact Radio Sources,’ Proceedings of the International Astronomical Union, 304, Yerevan, Armenia, (2014).

11. J. Y. Koay, J.-P. Macquart, B. J. Rickett, H. E. Bignall, D. Jauncey, T. Pursimo, C. Reynolds, J. E. J. Lovell, L. Kedziora-Chudczer, & R. Ojha, ‘The MASIV Legacy: Surveying AGN Intraday-Variability at Radio Wave- lengths,’ Proceedings of the International Astronomical Union, 304, Yerevan, Armenia, (2014).

12. H. E. Bignall, J. Y. Koay, J. E. J. Lovell, D. L. Jauncey, J.-P. Macquart, T. Pursimo, R. Ojha, B. J. Rickett, L. Kedziora-Chudczer, C. Reynolds, & S. Khoo, ‘Combining VLBI and MASIV: How Intrinsic Properties Influence Interstellar Scintillation of AGN,’ Proceedings of Resolving The Sky - Radio Interferometry: Past, Present and Future, Manchester, UK, (2012).

13. D. L. Jauncey, H. E. Bignall, L. Kedziora-Chudczer, J. Y. Koay, J. E. J. Lovell, J.-P. Macquart, R. Ojha, T. Pursimo, C. Reynolds, & B. J. Rickett, ‘Beyond VLBI: Microarcsecond Resolution with Interstellar Scintillation,’ Proceedings of Resolving The Sky - Radio Interferometry: Past, Present and Future, Manchester, UK, (2012).

14. J. Y. Koay, J.-P. Macquart, B. J. Rickett, H. E. Bignall, D. L. Jauncey, J. E. J. Lovell, C. Reynolds, T. Pursimo, L. Kedziora-Chudczer, & R. Ojha, ‘Interstellar Scintillation as a Cosmological Probe: Prospects and Challenges,’ Proceedings of the International Astronomical Union, 285, 347, (published 2012), Oxford, UK, (2011).

15. J. Y. Koay, J.-P. Macquart, B. J. Rickett, H. E. Bignall, J. E. J. Lovell, C. Reynolds, D. L. Jauncey, T. Pursimo, L. Kedziora-Chudczer, & R. Ojha, ‘Interstellar Scattering as a Cosmological Probe,’ Proceedings of the International Union of Radio Science (URSI) General Assembly and Scientific Symposium, Istanbul, Turkey, (2011).

16. H. Bignall, J. Y. Koay, J.-P. Macquart, J. Lovell, R. Ojha, M. Dutka, T. Pursimo, B. Rickett, D. Jauncey, & L. Kedziora-Chudczer, ‘On the Redshift Dependence of Scintillating AGN: Results of the MASIV Survey and Follow-Up Observations,’ Proceedings of the International Square Kilometre Array Forum (ISKAF) Science Meeting, Assen, Netherlands, (2010).

17. J. Y. Koay , T.  Y.  Yan, K. S. Lim & H. T. Ewe, ‘A Microwave Scattering Model for the Remote Sensing of Oil Palm Plantations,’ Proceedings of the Progress in Electromagnetics Research Symposium (PIERS), Beijing, China, (2009).

18. J. Y. Koay, H. T. Ewe, & H. T. Chuah, ‘Multitemporal Backscattering Behavior of Rice Crop Canopies Based on Dense Medium Model Simulations,’ Proceedings of the Progress in Electromagnetics Research Symposium (PIERS), Hangzhou, China, (2008).

19. J. Y. Koay, K. S. Lim, H. T. Ewe, H. T. Chuah, H. Jamil, & S. Bahari, ‘Preliminary Study in the Backscattering Measurements and Theoretical Modeling of Oil Palm Canopies,’ Proceedings of the Asian Conference on Remote Sensing (ACRS), Kuala Lumpur, Malaysia, (2007).

20. J. Y. Koay, H. T. Ewe, & H. T. Chuah, ‘Effects of Fresnel Corrections in the Scattered Field of General Ellipsoids,’ Proceedings of the Progress in Electromagnetics Research Symposium (PIERS), Beijing, China, (2007).

21. K. S. Lim, C. P. Tan, J. Y. Koay, V. C. Koo, H. T. Ewe, Y. C. Lo & A. Ali, ‘Multitemporal C-Band Radar Measurement on Rice Fields,’ Proceedings of the Progress in Electromagnetics Research Symposium (PIERS), Beijing, China, (2007).

22. J. Y. Koay, C. P. Tan, H. T. Ewe, & H. T. Chuah, ‘Theoretical Modeling and Analysis of Temporal Microwave Backscatter from Paddy Fields,’ Proceedings of the 4th National Microwave Remote Sensing Seminar, Kuala Lumpur, Malaysia, (2006).

23. K. S. Lim, S. Bahari, C. P. Tan, J. Y. Koay, M. Y. Chua, V. C. Koo, H. T. Ewe, A. Halim & M. Safid, ‘Rice Field Measurement Using C-Band Scatterometer,’ Proceedings of the 4th National Microwave Remote Sensing Seminar, Kuala Lumpur, Malaysia, (2006).

24. C. P. Tan, J. Y. Koay, H. T. Teng, H. T. Ewe, H. T. Chuah, & S. Bahari, ‘Image Classification of Rice Growth Stages using Combination of Entropy Decomposition and Support Vector Machine (EDSVM),’ Proceedings of the Pacific Rim AIRSAR Significant Results Symposium, Kuala Lumpur, Malaysia, (2006).

25. J. Y. Koay, C. P. Tan, H. T. Ewe, H. T. Chuah & S. Bahari, ‘Theoretical Modeling and Measurement Com- parison of Season-Long Rice Field Monitoring,’ Proceedings of the Progress in Electromagnetics Research Symposium (PIERS), Hangzhou, China, (2005).

MAGAZINE ARTICLES

1. J. Y. Koay, ‘To the Malaysian Scientist...’, Scientific Malaysian, 10, 42 (2015).

2. J. Y. Koay, ‘New Eyes on the Universe: The Square Kilometre Array’, Scientific Malaysian, 9, 22 (2014).