Ue-Li Pen

Ue-Li Pen profile picture
Canadian Institute for Theoretical Astrophysics (CITA)
Research Associate Faculty
Areas of research:
Cosmology
(519) 569-7600 x6282
If you are interested in pursuing a MSc degree, please apply to the Perimeter Scholars International (PSI) masters program. If you are interested in working with me as a PhD student, please send me an email at [email protected] or submit an application directly to my department at the University of Toronto and indicate that you would like to be supervised by me. Perimeter Institute is committed to diversity within its community and I welcome applications from underrepresented groups.
In the modern era where much of astrophysics operates in giant collaborations (e.g. CMB-S4, LIGO, EHT), my niche has been to explore short term innovative initiatives with large growth potential. 21cm cosmology is such an example, where I initiated the CHIME telescope in Canada, whose advantage in survey speed has changed the FRB field This exciting new development is leading to large samples of coherent light sources, essentially lasers at cosmological distances, which probe space-time with a strain h~10{-26}, the most precise probe available. New theoretical developments arose, including application of Picard-Lefschetz theory to address the wave optics path integrals, represented in a series of papers with Turok, Feldbrugge, Foreman, Jow and others. Cosmological opportunity lies in the smallest scales, with discovery space due to the large number of observable modes. Recently, we developed a theory of directed angular momentum, using the signed orientation of the galaxy on the sky as classified by spiral winding in the citizen-science galaxy zoo. This opens the potential to probe early helicity and non-Gaussianity, far beyond current constraints.
  • Director, Academia Sinica Institute of Astronomy & Astrophysics, 2021-present
  • Director, CITA, 2016-2019
  • Professor, CITA, 2011-present
  • Associate Professor, CITA, 2003-2011
  • Assistant Professor, CITA, 1998-2003
  • Junior Fellow, Harvard University, 1995-1998
  • Bustling Universe Radio Survey Telescope in Taiwan, National Science and Technology Council of Taiwan, 2022-2026
  • Lancelot Berkeley Prize, American Astronomical Society, 2022
  • Mapping the Environment of FRBs, National Science and Technology Council of Taiwan, 2021-2022
  • Large-Scale Structure: Cosmological Simulation, National Natural Science Foundation of China, 2021-2023
  • Breakthrough Prize in Fundamental Physics, Breakthrough Prize Foundation, 2020
  • Innovation Award, Governor General of Canada, 2020
  • NSERC Discovery Grant: Short time domain coherent radio astronomy, Natural Sciences and Engineering Research Council of Canada, 2019-2024
  • Grant, Simons Foundation, 2019-2024
  • Unlocking the Radio Universe, Canada Foundation for Innovation, 2018-2023
  • Discovery Grant: Pulsar Scintillometry, Natural Sciences and Engineering Research Council of Canada (NSERC), 2018-2022
  • Humboldt Research Award, Humboldt Foundation, 2018
  • Smart Handling of Big Data, Ministry of Research and Innovation, Province of Ontario, 2017-2023
  • Canadian VLBI, Canada Foundation for Innovation, 2016-2021
  • Lin, H. -H., Scholz, P., Ng, C., Pen, U. -L., Bhardwaj, M., Chawla, P., . . . Wulf, D. (2024). Do All Fast Radio Bursts Repeat? Constraints from CHIME/FRB Far Sidelobe FRBs. The Astrophysical Journal, 975(1), 75. doi:10.3847/1538-4357/ad779d
  • Baczko, A. -K., Kadler, M., Ros, E., Christian Fromm, M., Wielgus, M., Perucho, M., . . . Zhao, G. -Y. (n.d.). The putative center in NGC 1052. Astronomy & Astrophysics. doi:10.1051/0004-6361/202450898
  • Hewitt, D. M., Bhardwaj, M., Gordon, A. C., Kirichenko, A., Nimmo, K., Bhandari, S., . . . Yuan, J. P. (2024). A Repeating Fast Radio Burst Source in a Low-Luminosity Dwarf Galaxy.
  • Ding, J., Wang, X., Pen, U. -L., & Li, X. -D. (2024). Correlation-based Beam Calibration of 21 cm Intensity Mapping. The Astrophysical Journal Supplement Series, 274(2), 44. doi:10.3847/1538-4365/ad6f0a
  • Cassanelli, T., Leung, C., Sanghavi, P., Mena-Parra, J., Cary, S., Mckinven, R., . . . Tendulkar, S. P. (n.d.). A fast radio burst localized at detection to an edge-on galaxy using very-long-baseline interferometry. Nature Astronomy, 1-14. doi:10.1038/s41550-024-02357-x
  • Jow, D. L., Wu, X., & Pen, U. -L. (2024). Refractive lensing of scintillating FRBs by subparsec cloudlets in the multiphase CGM. Proceedings of the National Academy of Sciences of the United States of America, 121(39), e2406783121. doi:10.1073/pnas.2406783121
  • Zhu, H. -M., & Pen, U. -L. (2024). Systematic analysis of Parity-Violating modes. doi:10.48550/arxiv.2409.11400
  • Raymond, A. W., Doeleman, S. S., Asada, K., Blackburn, L., Bower, G. C., Bremer, M., . . . Zhao, S. -S. (2024). First Very Long Baseline Interferometry Detections at 870 µm. The Astronomical Journal, 168(3), 130. doi:10.3847/1538-3881/ad5bdb
  • Huang, Y. C., Koch, P. M., Hwang, Y. -J., Chiong, C. -C., Yen, H. -W., Ho, P., . . . Wang, C. -C. (2024). Lessons learned: ALMA band-1 receiver project management. In Proceedings of SPIE--the International Society for Optical Engineering Vol. 13099 (pp. 130991y-130991y-3). SPIE, the international society for optics and photonics. doi:10.1117/12.3018608
  • Dahal, S., Ade, P. A. R., Anderson, C. J., Barlis, A., Barrentine, E. M., Beeman, J. W., . . . Yung, A. (2024). Superfluid-tight cryogenic receiver with continuous sub-kelvin cooling for EXCLAIM. In Proceedings of SPIE--the International Society for Optical Engineering Vol. 13102 (pp. 131022i-131022i-13). SPIE, the international society for optics and photonics. doi:10.1117/12.3018577
  • Liu, K. -Y., Tan, B. -K., Wang, M. -J., Kittara, P., Singwong, D., Janphuang, P., . . . Bintley, D. (2024). Development of 230 GHz finline SIS mixers for next-generation large array receivers and HARP instrument upgrade. In Proceedings of SPIE--the International Society for Optical Engineering Vol. 13102 (pp. 1310228-1310228-9). SPIE, the international society for optics and photonics. doi:10.1117/12.3018151
  • Tsai, A., Jow, D. L., Baker, D., & Pen, U. -L. (2024). Scintillated microlensing: Measuring cosmic distances with fast radio bursts. Physical Review D, 110(4), 043503. doi:10.1103/physrevd.110.043503
  • Ding, J., Wang, X., Pen, U. -L., & Li, X. -D. (2024). Correlation-based Beam Calibration of 21cm Intensity Mapping. doi:10.48550/arxiv.2408.06682
  • Yu, Z., Deng, F., Sun, S., Niu, C., Li, J., Wu, F., . . . Chen, X. (2024). The FRB-searching Pipeline of the Tianlai Cylinder Pathfinder Array. Research in Astronomy and Astrophysics, 24(8), 085010. doi:10.1088/1674-4527/ad5b35
  • Amiri, M., Chakraborty, A., Foreman, S., Halpern, M., Hill, A. S., Hinshaw, G., . . . Wulf, D. (2024). Holographic Beam Measurements of the Canadian Hydrogen Intensity Mapping Experiment (CHIME). doi:10.48550/arxiv.2408.00172
  • Hu, W., Wang, Y., Li, Y., Pen, U. -L., Wang, J., Jing, Y., . . . Chen, X. (2024). The FAST HI 21-cm absorption blind survey. II -- statistic exploration for associated and intervening systems. doi:10.48550/arxiv.2407.14411
  • Jow, D. L., & Pen, U. -L. (2024). Measuring cosmic expansion with diffractive gravitational scintillation of nanoHertz gravitational waves. doi:10.48550/arxiv.2407.03214
  • Collaboration, T. C. F., Amiri, M., Andersen, B. C., Andrew, S., Bandura, K., Bhardwaj, M., . . . Wulf, D. (2024). Updating the First CHIME/FRB Catalog of Fast Radio Bursts with Baseband Data. The Astrophysical Journal, 969(2), 145. doi:10.3847/1538-4357/ad464b
  • Yu, Z., Deng, F., Sun, S., Niu, C., Li, J., Wu, F., . . . Chen, X. (2024). The FRB-searching pipeline of the Tianlai Cylinder Pathfinder Array. doi:10.48550/arxiv.2406.15740
  • Shim, J., Pen, U. -L., Yu, H. -R., & Okumura, T. (2024). Probing vector chirality in the early Universe. doi:10.48550/arxiv.2406.06080
  • Li, D., & Pen, U. -L. (2024). FRBs from rapid spin-down neutron stars. Monthly Notices of the Royal Astronomical Society, 531(2), 2330-2334. doi:10.1093/mnras/stae1190
  • Collaboration, T. E. H. T., Akiyama, K., Alberdi, A., Alef, W., Algaba, J. C., Anantua, R., . . . Najafi-Ziyazi. (2024). First Sagittarius A* Event Horizon Telescope Results. VIII. Physical Interpretation of the Polarized Ring. The Astrophysical Journal Letters, 964(2), l26. doi:10.3847/2041-8213/ad2df1
  • Collaboration, T. E. H. T., Akiyama, K., Alberdi, A., Alef, W., Algaba, J. C., Anantua, R., . . . Zhao, S. -S. (2024). First Sagittarius A* Event Horizon Telescope Results. VII. Polarization of the Ring. The Astrophysical Journal Letters, 964(2), l25. doi:10.3847/2041-8213/ad2df0
  • Amiri, M., Bandura, K., Chakraborty, A., Dobbs, M., Fandino, M., Foreman, S., . . . Collaboration, T. C. (2024). A Detection of Cosmological 21 cm Emission from CHIME in Cross-correlation with eBOSS Measurements of the Lya Forest. The Astrophysical Journal, 963(1), 23. doi:10.3847/1538-4357/ad0f1d
  • Jow, D. L., Pen, U. -L., & Baker, D. (2024). On the cusp of cusps: a universal model for extreme scattering events in the ISM. Monthly Notices of the Royal Astronomical Society, 528(4), 6292-6301. doi:10.1093/mnras/stae300
  • Paraschos, G. F., Kim, J. -Y., Wielgus, M., Röder, J., Krichbaum, T. P., Ros, E., . . . Zhao, S. -S. (2024). Ordered magnetic fields around the 3C 84 central black hole. Astronomy & Astrophysics, 682, l3. doi:10.1051/0004-6361/202348308
  • Zang, S. -H., Zhu, H. -M., Schmittfull, M., & Pen, U. -L. (2024). Cosmic Tidal Reconstruction in Redshift Space. The Astrophysical Journal, 962(1), 21. doi:10.3847/1538-4357/ad0cf0
  • Akiyama, K., Alberdi, A., Alef, W., Algaba, J. C., Anantua, R., Asada, K., . . . Yu, C. -Y. (2024). The persistent shadow of the supermassive black hole of M 87. Astronomy & Astrophysics, 681, a79. doi:10.1051/0004-6361/202347932
  • Koay, J. Y., Asada, K., Matsushita, S., Kuo, C. -Y., Huang, C. -W. L., Romero-Cañizales, C., . . . Wei, T. -S. (2023). Absolute Flux Density Calibration of the Greenland Telescope Data for Event Horizon Telescope Observations. arxiv:2312.02759v1
  • Torne, P., Liu, K., Eatough, R. P., Wongphechauxsorn, J., Cordes, J. M., Desvignes, G., . . . Zhao, S. -S. (2023). A Search for Pulsars around Sgr A* in the First Event Horizon Telescope Data Set. The Astrophysical Journal, 959(1), 14. doi:10.3847/1538-4357/acf4f2
  • Collaboration, T. E. H. T., Akiyama, K., Alberdi, A., Alef, W., Algaba, J. C., Anantua, R., . . . Zhao, S. -S. (2023). First M87 Event Horizon Telescope Results. IX. Detection of Near-horizon Circular Polarization. The Astrophysical Journal Letters, 957(2), l20. doi:10.3847/2041-8213/acff70
  • Roelofs, F., Johnson, M. D., Chael, A., Janssen, M., Wielgus, M., Broderick, A. E., . . . Zhao, S. -S. (2023). Polarimetric Geometric Modeling for mm-VLBI Observations of Black Holes. The Astrophysical Journal Letters, 957(2), l21. doi:10.3847/2041-8213/acff6f
  • Collaboration, T. C. F., :., Amiri, M., Andersen, B. C., Andrew, S., Bandura, K., . . . Wulf, D. (2023). Updating the first CHIME/FRB catalog of fast radio bursts with baseband data. doi:10.48550/arxiv.2311.00111
  • Feldbrugge, J., Jow, D. L., & Pen, U. -L. (2023). Complex classical paths in quantum reflections and tunneling. doi:10.48550/arxiv.2309.12420
  • Feldbrugge, J., Jow, D. L., & Pen, U. -L. (2023). Crossing singularities in the saddle point approximation. doi:10.48550/arxiv.2309.12427
  • Li, D., & Pen, U. -L. (2023). FRBs from rapid spindown neutron stars. doi:10.48550/arxiv.2309.06328
  • CHIME Collaboration., Amiri, M., Bandura, K., Chakraborty, A., Dobbs, M., Fandino, M., . . . Wulf, D. (2023). A Detection of Cosmological 21 cm Emission from CHIME in Cross-correlation with eBOSS Measurements of the Lyman-$\alpha$ Forest. doi:10.48550/arxiv.2309.04404
  • Torne, P., Liu, K., Eatough, R. P., Wongphechauxsorn, J., Cordes, J. M., Desvignes, G., . . . Zhao, S. -S. (2023). A search for pulsars around Sgr A* in the first Event Horizon Telescope dataset. doi:10.48550/arxiv.2308.15381
  • Jow, D. L., Pen, U. -L., & Feldbrugge, J. (2023). Regimes in astrophysical lensing: refractive optics, diffractive optics, and the Fresnel scale. Monthly Notices of the Royal Astronomical Society, 525(2), 2107-2124. doi:10.1093/mnras/stad2332
  • Tsai, A., Jow, D. L., Baker, D., & Pen, U. -L. (2023). Scintillated microlensing: measuring cosmic distances with fast radio bursts. doi:10.48550/arxiv.2308.10830
  • Baker, D., Brisken, W., van Kerkwijk, M. H., van Lieshout, R., & Pen, U. -L. (2023). High-resolution VLBI astrometry of pulsar scintillation screens with the ? - ? transform. Monthly Notices of the Royal Astronomical Society, 525(1), 211-220. doi:10.1093/mnras/stad2318
  • Lin, R., van Kerkwijk, M. H., Kirsten, F., Pen, U. -L., & Deller, A. T. (2023). The Radio Parallax of the Crab Pulsar: A First VLBI Measurement Calibrated with Giant Pulses. The Astrophysical Journal, 952(2), 161. doi:10.3847/1538-4357/acdc98
  • Lin, H. -H., Scholz, P., Ng, C., Pen, U. -L., Bhardwaj, M., Chawla, P., . . . Wulf, D. (2023). Do All Fast Radio Bursts Repeat? Constraints from CHIME/FRB Far Side-Lobe FRBs. doi:10.48550/arxiv.2307.05261
  • Lin, H. -H., Scholz, P., Ng, C., Pen, U. -L., Li, D. Z., Newburgh, L., . . . Wulf, D. (2023). Constraints on the Intergalactic and Local Dispersion Measure of Fast Radio Bursts with the CHIME/FRB far side-lobe events. doi:10.48550/arxiv.2307.05262
  • Hu, W., Wang, Y., Li, Y., Xu, Y., Yang, W., Lagache, G., . . . Chen, X. (2023). Detections of 21 cm absorption with a blind FAST survey at z = 0.09. Astronomy & Astrophysics, 675, a40. doi:10.1051/0004-6361/202245549
  • Chung, C. L., Inman, D., Wang, X., Shang, E., Zhuang, Z., Yuan, F., & Pen, U. -L. (2023). Neutrino Mass Constraints from Reconstructing the Large-scale Structure: Systematic Uncertainty. Research in Astronomy and Astrophysics, 23(6), 065007. doi:10.1088/1674-4527/accb7c
  • Prather, B. S., Dexter, J., Moscibrodzka, M., Pu, H. -Y., Bronzwaer, T., Davelaar, J., . . . Collaboration, T. E. H. T. (2023). Comparison of Polarized Radiative Transfer Codes Used by the EHT Collaboration. The Astrophysical Journal, 950(1), 35. doi:10.3847/1538-4357/acc586
  • Zhu, H., Baker, D., Pen, U. -L., Stinebring, D. R., & van Kerkwijk, M. H. (2023). Pulsar Double Lensing Sheds Light on the Origin of Extreme Scattering Events. The Astrophysical Journal, 950(2), 109. doi:10.3847/1538-4357/accde0
  • Er, X., Pen, U. -L., Sun, X., & Li, D. (2023). Plasma lensing with magnetic field and a small correction to the Faraday rotation measurement. Monthly Notices of the Royal Astronomical Society, 522(3), 3965-3971. doi:10.1093/mnras/stad1282
  • Lu, R. -S., Asada, K., Krichbaum, T. P., Park, J., Tazaki, F., Pu, H. -Y., . . . Yu, C. -Y. (2023). A ring-like accretion structure in M87 connecting its black hole and jet. Nature, 616(7958), 686-690. doi:10.1038/s41586-023-05843-w
  • Sanghavi, P., Leung, C., Bandura, K., Cassanelli, T., Kaczmarek, J., Kaspi, V. M., . . . Shah, V. (2023). TONE: A CHIME/FRB Outrigger Pathfinder for localizations of Fast Radio Bursts using Very Long Baseline Interferometry. doi:10.48550/arxiv.2304.10534
  • Collaboration, T. C. F., Andersen, B. C., Bandura, K., Bhardwaj, M., Boyle, P. J., Brar, C., . . . Zwaniga, A. (2023). CHIME/FRB Discovery of 25 Repeating Fast Radio Burst Sources. The Astrophysical Journal, 947(2), 83. doi:10.3847/1538-4357/acc6c1
  • Feldbrugge, J., Pen, U. -L., & Turok, N. (2023). Oscillatory path integrals for radio astronomy. Annals of Physics, 451, 169255. doi:10.1016/j.aop.2023.169255
  • Collaboration, T. C., Amiri, M., Bandura, K., Chen, T., Deng, M., Dobbs, M., . . . Wulf, D. (2023). Detection of Cosmological 21 cm Emission with the Canadian Hydrogen Intensity Mapping Experiment. The Astrophysical Journal, 947(1), 16. doi:10.3847/1538-4357/acb13f
  • Lin, R., van Kerkwijk, M. H., Main, R., Mahajan, N., Pen, U. -L., & Kirsten, F. (2023). Resolving the Emission Regions of the Crab Pulsar’s Giant Pulses. II. Evidence for Relativistic Motion. The Astrophysical Journal, 945(2), 115. doi:10.3847/1538-4357/acba95
  • Jorstad, S., Wielgus, M., Lico, R., Issaoun, S., Broderick, A. E., Pesce, D. W., . . . Zhao, S. -S. (2023). The Event Horizon Telescope Image of the Quasar NRAO 530. The Astrophysical Journal, 943(2), 170. doi:10.3847/1538-4357/acaea8
  • Collaboration, T. C. F., Amiri, M., Andersen, B. C., Bandura, K., Berger, S., Bhardwaj, M., . . . Zwaniga, A. V. (2023). Erratum: “The First CHIME/FRB Fast Radio Burst Catalog” (2021, ApJS, 257, 59). The Astrophysical Journal Supplement Series, 264(2), 53. doi:10.3847/1538-4365/acb54c
  • Jow, D. L., Pen, U. -L., & Baker, D. (2023). On the cusp of cusps: a universal model for extreme scattering events in the ISM. doi:10.48550/arxiv.2301.08344
  • Jia, H., Zhu, H. -M., & Pen, U. -L. (2023). Galaxy Spin Classification. I. Z-wise versus S-wise Spirals with the Chirality Equivariant Residual Network. The Astrophysical Journal, 943(1), 32. doi:10.3847/1538-4357/aca8aa
  • Baker, D., & Pen, U. -L. (2023). Imaging Pulsar Scintillation Screens Using Earth-Space VLBI. In Proceedings of the XXXVth URSI General Assembly and Scientific Symposium – GASS 2023. International Union of Radio Science (URSI). doi:10.46620/ursigass.2023.3099.uqjd6666
  • Lin, F. X., Main, R. A., Jow, D., Li, D. Z., Pen, U. -L., & van Kerkwijk, M. H. (2022). Plasma lensing near the eclipses of the Black Widow pulsar B1957+20. Monthly Notices of the Royal Astronomical Society, 519(1), 121-135. doi:10.1093/mnras/stac3456
  • Zang, S. -H., Zhu, H. -M., Schmittfull, M., & Pen, U. -L. (2022). Cosmic tidal reconstruction in redshift space. doi:10.48550/arxiv.2212.04294
  • Baker, D., Brisken, W., van Kerkwijk, M. H., van Lieshout, R., & Pen, U. -L. (2022). High Resolution VLBI Astrometry of pulsar scintillation screens with the $\theta-\theta$ Transform. doi:10.48550/arxiv.2212.01417
  • Lin, H. -H., Lin, K. -Y., Li, C. -T., Tseng, Y. -H., Jiang, H., Wang, J. -H., . . . Zhu, H. -M. (2022). BURSTT: Bustling Universe Radio Survey Telescope in Taiwan. Publications of the Astronomical Society of the Pacific, 134(1039), 094106. doi:10.1088/1538-3873/ac8f71
  • Essinger-Hileman, T., Ade, P., Anderson, C. J., Barlis, A., Barrentine, E. M., Beeman, J., . . . Yung, L. Y. A. (2022). EXCLAIM: the EXperiment for Cryogenic Large-Aperture Intensity Mapping. In Proceedings of SPIE--the International Society for Optical Engineering Vol. 12190 (pp. 1219009-1219009-9). SPIE, the international society for optics and photonics. doi:10.1117/12.2630054
  • Lin, H. -H., Main, R., Pen, U. -L., Wharton, R., Bause, M. L., Bethapudi, S., . . . Spitler, L. G. (2022). DM-power: an algorithm for high precision dispersion measure with application to fast radio bursts. doi:10.48550/arxiv.2208.13677
  • Yalinewich, A., & Pen, U. -L. (2022). The moving mirror model for fast radio bursts. Monthly Notices of the Royal Astronomical Society, 515(4), 5682-5688. doi:10.1093/mnras/stac2087
  • Leung, C., Kader, Z., Masui, K. W., Dobbs, M., Michilli, D., Mena-Parra, J., . . . Vanderlinde, K. (2022). Constraining primordial black holes using fast radio burst gravitational-lens interferometry with CHIME/FRB. Physical Review D, 106(4), 043017. doi:10.1103/physrevd.106.043017
  • Kader, Z., Leung, C., Dobbs, M., Masui, K. W., Michilli, D., Mena-Parra, J., . . . Wulf, D. (2022). High-time resolution search for compact objects using fast radio burst gravitational lens interferometry with CHIME/FRB. Physical Review D, 106(4), 043016. doi:10.1103/physrevd.106.043016
  • Amiri, M., Bandura, K., Boskovic, A., Chen, T., Cliche, J. -F., Deng, M., . . . Wulf, D. (2022). An Overview of CHIME, the Canadian Hydrogen Intensity Mapping Experiment. The Astrophysical Journal Supplement Series, 261(2), 29. doi:10.3847/1538-4365/ac6fd9
  • Issaoun, S., Wielgus, M., Jorstad, S., Krichbaum, T. P., Blackburn, L., Janssen, M., . . . Zhao, S. -S. (2022). Resolving the Inner Parsec of the Blazar J1924–2914 with the Event Horizon Telescope. The Astrophysical Journal, 934(2), 145. doi:10.3847/1538-4357/ac7a40
  • Andersen, B. C., Bandura, K., Bhardwaj, M., Boyle, P. J., Brar, C., Breitman, D., . . . Zwaniga, A. (2022). Sub-second periodicity in a fast radio burst. Nature, 607(7918), 256-259. doi:10.1038/s41586-022-04841-8
  • Jow, D. L., & Pen, U. -L. (2022). Measuring lens dimensionality in extreme scattering events through wave optics. Monthly Notices of the Royal Astronomical Society, 514(3), 4069-4077. doi:10.1093/mnras/stac1652
  • Georgiev, B., Pesce, D. W., Broderick, A. E., Wong, G. N., Dhruv, V., Wielgus, M., . . . Zhao, S. -S. (2022). A Universal Power-law Prescription for Variability from Synthetic Images of Black Hole Accretion Flows. The Astrophysical Journal Letters, 930(2), l20. doi:10.3847/2041-8213/ac65eb
  • Collaboration, E. H. T., Akiyama, K., Alberdi, A., Alef, W., Algaba, J. C., Anantua, R., . . . Zhao, S. -S. (2022). First Sagittarius A* Event Horizon Telescope Results. VI. Testing the Black Hole Metric. The Astrophysical Journal Letters, 930(2), l17. doi:10.3847/2041-8213/ac6756
  • Collaboration, E. H. T., Akiyama, K., Alberdi, A., Alef, W., Algaba, J. C., Anantua, R., . . . Chang, D. O. (2022). First Sagittarius A* Event Horizon Telescope Results. IV. Variability, Morphology, and Black Hole Mass. The Astrophysical Journal Letters, 930(2), l15. doi:10.3847/2041-8213/ac6736
  • Collaboration, E. H. T., Akiyama, K., Alberdi, A., Alef, W., Algaba, J. C., Anantua, R., . . . Wouterloot, J. G. A. (2022). First Sagittarius A* Event Horizon Telescope Results. II. EHT and Multiwavelength Observations, Data Processing, and Calibration. The Astrophysical Journal Letters, 930(2), l13. doi:10.3847/2041-8213/ac6675
  • Collaboration, E. H. T., Akiyama, K., Alberdi, A., Alef, W., Algaba, J. C., Anantua, R., . . . Zeballos, M. (2022). First Sagittarius 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(2), l12. doi:10.3847/2041-8213/ac6674
  • Collaboration, E. H. T., Akiyama, K., Alberdi, A., Alef, W., Algaba, J. C., Anantua, R., . . . White, C. (2022). First Sagittarius A* Event Horizon Telescope Results. V. Testing Astrophysical Models of the Galactic Center Black Hole. The Astrophysical Journal Letters, 930(2), l16. doi:10.3847/2041-8213/ac6672
  • Farah, J., Galison, P., Akiyama, K., Bouman, K. L., Bower, G. C., Chael, A., . . . Zhao, S. -S. (2022). Selective Dynamical Imaging of Interferometric Data. The Astrophysical Journal Letters, 930(2), l18. doi:10.3847/2041-8213/ac6615
  • Broderick, A. E., Gold, R., Georgiev, B., Pesce, D. W., Tiede, P., Ni, C., . . . Zhao, S. -S. (2022). Characterizing and Mitigating Intraday Variability: Reconstructing Source Structure in Accreting Black Holes with mm-VLBI. The Astrophysical Journal Letters, 930(2), l21. doi:10.3847/2041-8213/ac6584
  • Collaboration, E. H. T., Akiyama, K., Alberdi, A., Alef, W., Algaba, J. C., Anantua, R., . . . Zhao, S. -S. (2022). First Sagittarius A* Event Horizon Telescope Results. III. Imaging of the Galactic Center Supermassive Black Hole. The Astrophysical Journal Letters, 930(2), l14. doi:10.3847/2041-8213/ac6429
  • Wielgus, M., Marchili, N., Martí-Vidal, I., Keating, G. K., Ramakrishnan, V., Tiede, P., . . . Zhao, S. -S. (2022). Millimeter Light Curves of Sagittarius A* Observed during the 2017 Event Horizon Telescope Campaign. The Astrophysical Journal Letters, 930(2), l19. doi:10.3847/2041-8213/ac6428
  • Motloch, P., Pen, U. -L., & Yu, H. -R. (2022). Observational search for primordial chirality violations using galaxy angular momenta. Physical Review D, 105(8), 083512. doi:10.1103/physrevd.105.083512
  • Motloch, P., Pen, U. -L., & Yu, H. -R. (2022). Correlating galaxy shapes and initial conditions: An observational study. Physical Review D, 105(8), 083504. doi:10.1103/physrevd.105.083504
  • Zhu, H. -M., Mao, T. -X., & Pen, U. -L. (2022). Cosmic Tidal Reconstruction with Halo Fields. The Astrophysical Journal, 929(1), 5. doi:10.3847/1538-4357/ac5a47
  • Kirsten, F., Marcote, B., Nimmo, K., Hessels, J. W. T., Bhardwaj, M., Tendulkar, S. P., . . . Vlemmings, W. (2022). A repeating fast radio burst source in a globular cluster. Nature, 602(7898), 585-589. doi:10.1038/s41586-021-04354-w
  • Tyhurst, E., Padmanabhan, H., & Pen, U. -L. (2022). Redshift space distortions in Lagrangian space and the linear large scale velocity field of dark matter. doi:10.48550/arxiv.2202.08435
  • Cassanelli, T., Leung, C., Rahman, M., Vanderlinde, K., Mena-Parra, J., Cary, S., . . . Tendulkar, S. P. (2022). Localizing FRBs through VLBI with the Algonquin Radio Observatory 10 m Telescope. The Astronomical Journal, 163(2), 65. doi:10.3847/1538-3881/ac3d2f
  • Baker, D., Brisken, W., van Kerkwijk, M. H., Main, R., Pen, U. -L., Sprenger, T., & Wucknitz, O. (2022). Interstellar interferometry: precise curvature measurement from pulsar secondary spectra. Monthly Notices of the Royal Astronomical Society, 510(3), 4573-4581. doi:10.1093/mnras/stab3599
  • Wolz, L., Pourtsidou, A., Masui, K. W., Chang, T. -C., Bautista, J. E., Müller, E. -M., . . . Zhao, G. -B. (2022). H i constraints from the cross-correlation of eBOSS galaxies and Green Bank Telescope intensity maps. Monthly Notices of the Royal Astronomical Society, 510(3), 3495-3511. doi:10.1093/mnras/stab3621
  • Satapathy, K., Psaltis, D., Özel, F., Medeiros, L., Dougall, S. T., Chan, C. -K., . . . Zhao, S. -S. (2022). The Variability of the Black Hole Image in M87 at the Dynamical Timescale. The Astrophysical Journal, 925(1), 13. doi:10.3847/1538-4357/ac332e
  • Feldbrugge, J. L., Pen, U. -L., & Turok, N. (2022). Oscillatory Path Integrals for Radio Astronomy. doi:10.2139/ssrn.4310424
  • Collaboration, T. C. F., Amiri, M., Andersen, B. C., Bandura, K., Berger, S., Bhardwaj, M., . . . Zwaniga, A. V. (2021). The First CHIME/FRB Fast Radio Burst Catalog. The Astrophysical Journal Supplement Series, 257(2), 59. doi:10.3847/1538-4365/ac33ab
  • Marthi, V. R., Bethapudi, S., Main, R. A., Lin, H. -H., Spitler, L. G., Wharton, R. S., . . . Hilmarsson, G. H. (n.d.). Burst properties of the highly active FRB20201124A using uGMRT. Monthly Notices of the Royal Astronomical Society, 509(2), 2209-2219. doi:10.1093/mnras/stab3067
  • Lin, F. X., Lin, H. -H., Luo, J., Main, R., McKee, J., Pen, U. -L., . . . van Kerkwijk, M. H. (2021). Profile changes associated with dispersion measure events in PSR J1713+0747. Monthly Notices of the Royal Astronomical Society, 508(1), 1115-1127. doi:10.1093/mnras/stab2529
  • Switzer, E. R., Barrentine, E. M., Cataldo, G., Essinger-Hileman, T., Ade, P. A. R., Anderson, C. J., . . . Yung, L. Y. A. (2021). Experiment for cryogenic large-aperture intensity mapping: instrument design. Journal of Astronomical Telescopes Instruments and Systems, 7(4), 044004. doi:10.1117/1.jatis.7.4.044004
  • Bij, A., Lin, H. -H., Li, D., van Kerkwijk, M. H., Pen, U. -L., Lu, W., . . . Vanderlinde, K. (2021). Kinematics of Crab Giant Pulses. The Astrophysical Journal, 920(1), 38. doi:10.3847/1538-4357/ac1589
  • Janssen, M., Falcke, H., Kadler, M., Ros, E., Wielgus, M., Akiyama, K., . . . van Bemmel, I. (2021). Event Horizon Telescope observations of the jet launching and collimation in Centaurus A. Nature Astronomy, 5(10), 1017-1028. doi:10.1038/s41550-021-01417-w
  • Jow, D. L., Lin, F. X., Tyhurst, E., & Pen, U. -L. (2021). Imaginary images and Stokes phenomena in the weak plasma lensing of coherent sources. Monthly Notices of the Royal Astronomical Society, 507(4), 5390-5402. doi:10.1093/mnras/stab2337
  • Marthi, V. R., Simard, D., Main, R. A., Pen, U. -L., van Kerkwijk, M. H., Vanderlinde, K., . . . Quine, B. M. (2021). Scintillation of PSR B1508+55 – the view from a 10 000-km baseline. Monthly Notices of the Royal Astronomical Society, 506(4), 5160-5169. doi:10.1093/mnras/stab1970
  • Tuntsov, A., Pen, U. -L., & Walker, M. (2021). Down-drifting, bandwidth and beaming of fast radio bursts. doi:10.48550/arxiv.2107.13549
  • Collaboration, T. C. F., Andersen, B. C., Bandura, K., Bhardwaj, M., Boyle, P. J., Brar, C., . . . Zwaniga, A. (2021). Sub-second periodicity in a fast radio burst. doi:10.48550/arxiv.2107.08463
  • Main, R., Lin, R., van Kerkwijk, M. H., Pen, U. -L., Rudnitskii, A. G., Popov, M. V., . . . Lyutikov, M. (2021). Resolving the Emission Regions of the Crab Pulsar’s Giant Pulses. The Astrophysical Journal, 915(1), 65. doi:10.3847/1538-4357/ac01c6
  • Kocherlakota, P., Rezzolla, L., Falcke, H., Fromm, C. M., Kramer, M., Mizuno, Y., . . . Zhao, S. -S. (2021). Constraints on black-hole charges with the 2017 EHT observations of M87*. Physical Review D, 103(10), 104047. doi:10.1103/physrevd.103.104047
  • Narayan, R., Palumbo, D. C. M., Johnson, M. D., Gelles, Z., Himwich, E., Chang, D. O., . . . Zhao, S. -S. (2021). The Polarized Image of a Synchrotron-emitting Ring of Gas Orbiting a Black Hole. The Astrophysical Journal, 912(1), 35. doi:10.3847/1538-4357/abf117
  • Motloch, P., Yu, H. -R., Pen, U. -L., & Xie, Y. (2021). Author Correction: An observed correlation between galaxy spins and initial conditions. Nature Astronomy, 5(5), 520-521. doi:10.1038/s41550-021-01340-0
  • Group, T. E. M. S. W., Algaba, J. C., Anczarski, J., Asada, K., Balokovic, M., Chandra, S., . . . Yonekura, Y. (2021). Broadband Multi-wavelength Properties of M87 during the 2017 Event Horizon Telescope Campaign. The Astrophysical Journal Letters, 911(1), l11. doi:10.3847/2041-8213/abef71
  • Motloch, P., Yu, H. -R., Pen, U. -L., & Xie, Y. (2021). An observed correlation between galaxy spins and initial conditions. Nature Astronomy, 5(3), 283-288. doi:10.1038/s41550-020-01262-3
  • Goddi, C., Martí-Vidal, I., Messias, H., Bower, G. C., Broderick, A. E., Dexter, J., . . . Valtonen, M. (2021). Polarimetric Properties of Event Horizon Telescope Targets from ALMA. The Astrophysical Journal Letters, 910(1), l14. doi:10.3847/2041-8213/abee6a
  • Akiyama, K., Algaba, J. C., Alberdi, A., Alef, W., Anantua, R., Asada, K., . . . Zhao, S. -S. (2021). First M87 Event Horizon Telescope Results. VII. Polarization of the Ring. The Astrophysical Journal Letters, 910(1), l12. doi:10.3847/2041-8213/abe71d
  • Akiyama, K., Algaba, J. C., Alberdi, A., Alef, W., Anantua, R., Asada, K., . . . Zhao, S. -S. (2021). First M87 Event Horizon Telescope Results. VIII. Magnetic Field Structure near The Event Horizon. The Astrophysical Journal Letters, 910(1), l13. doi:10.3847/2041-8213/abe4de
  • Wucknitz, O., Spitler, L. G., & Pen, U. -L. (2021). Cosmology with gravitationally lensed repeating fast radio bursts. Astronomy & Astrophysics, 645, a44. doi:10.1051/0004-6361/202038248
  • FRBs: what are they and what are they good for?, Tohoku University, 2024/04/15
  • Options for the Universe, Hunan Normal University, Changsha, China, 2024/02/27
  • Systematic generation of helical parity violating initial conditions: vector and tensor types, Institute of Astronomy and Astrophysics, Academia Sinica, Taipei, Taiwan, 2023/12/06
  • Picard-Lefschetz Interpretation of Cosmic Lensing and Beyond, The Chinese University of Hong Kong, 2023/11/10
  • The Universe viewed with Wave Optics, Sun Yat-sen University, 2023/10/10
  • Why do galaxies rotate?, National Chung Hsing University, Department of Physics, 2023/03/10
  • Imaginary images: FRBs, quantum mechanics and quantum cosmology, National Chung Cheng University, 2023/02/15
  • Magnetic Helicity, National Center for Theoretical Sciences, 2023/02/04
  • Magnetic Helicity, National Center for Manufacturing Sciences, Ann Arbor, United States, 2023/01/18
  • Classical Mechanics, Quantum Mechanics, Quantum Cosmology: new view on the universe, National Cheng Kung University, 2023/01/18
  • images: FRBs, quantum mechanics and quantum cosmology, National Cheng Kung University, 2023/01/06
  • Wave particle duality revisited: Picard-Lefschetz interpretation in astrophysics, quantum cosmology and beyond, Academia Sinica, Institute of Physics, Taipei, Taiwan, 2022/11/18
  • Black Hole, Academia Sinica Open House, 2022/10/29
  • Surveying the nearest FRBs, Cornell University, 2022/10/11
  • Cosmological scalar helicity, Kavli Institute for the Physics and Mathematics of the Universe, 2022/09/15
  • Imaginary Paths: new tools for cosmology, GW, FRBs, Association of Asia Pacific Physical Societies, 2022/08/26
  • Turok-Witten-Picard-Lefschetz quantum mechanics and quantum gravity, National Taiwan University, Taipei, Taiwan, 2022/04/11
  • Classical Mechanics, Quantum Mechanics, Quantum Cosmology: How the universe may have begun, National Yang Ming Chiao Tung University, 2022/03/03
  • Why do spiral galaxies rotate, and what can we learn from that?, Astronomy on Tap, Taipei, Taiwan, 2022/01/21
  • Probing the universe with Fast Radio Bursts, Canadian Institute for Theoretical Astrophysics(CITA), 2022/01/01
  • FRB Physics, National Central University, 2022/01/01
  • BURSTT: Taiwan all sky FRB survey, IAU-369 New projects talk, 2022/01/01
  • Classical and quantum completeness of transient black hole space times, National Taiwan University, Taipei, Taiwan, 2022/01/01
  • From GRBs, Baryogenesis to FRBs, Astrophysics in the Next Decade: From the First Stars to Intelligent Life (CIERA conference), 2022/01/01
  • Classical Mechanics, Quantum Mechanics, Quantum Cosmology: new view on the universe, National Changhua University of Education, 2022/01/01