Siyi Xu Assistant Astronomer Office: 314 Gemini Observatory (North) Phone: +01 808-974-2538 670 N. A’ohoku Place Email: [email protected] Hilo, Hawaii, 96720, USA Webpage: http://staff.gemini.edu/sxu/

Work Experience

2017 – present Assistant Astronomer, Science Operations Gemini Observatory, Hilo, USA Tenure•track astronomer, 50% for research and 50% for observatory support work

2014 – 2017 Postdoctoral Fellow, Directorate for science European Southern Observatory, Garching, Germany Independent research fellowship

2014 – 2017 Fellow Astronomer, Paranal Observatory Science Operations ESO Paranal Observatory/ Very Large Telescope, Chile ESO duties, 40 nights per year. In charge of science operation of the telescope, including X•SHOOTER, UVES, and FLAMES, quality assessment of the data, and support of visitors.

Education

2010 – 2014 Ph.D. Astronomy, Advisor: Michael A. Jura University of California, Los Angeles, USA

2006 – 2010 B.S. Astronomy Nanjing University, China

Short-term Positions

October 2016 Lyon Observatory & ENS de Lyon Visiting Astronomer Planet Formation Group & Cosmochemistry Group

Summer 2009 University of California, Los Angeles Visiting Student Cross-disciplinary Scholars in Science and Technology

S. Xu | Curriculum Vitae 1/6 Grants & Awards

Telescope Time as Hubble Space Telescope Principal Investigator Cycle 25 (2017), GO #15155, 12 orbits Cycle 24 (2016), GO #14646, 12 orbits Cycle 23 (2015), GO #14467, 5 orbits Cycle 23 (2015), GO #14117, 1 orbit

Very Large Telescope 099.C-0082 (2017) HAWKI (8.0 hr) 099.C-0264 (2017), 60.A-9373: Science Verification (2014) SPHERE (6.1 hr in total) 296.C-0524: DDT (2016) X-SHOOTER (5 hr); FORS2 (5 hr); HAWKI (5 hr) 095.C-0439, 095.C-0564, 096.C-0132, 096.C-0135 (2015) UVES (24.8 hr in total)

Spitzer Space Telescope Cycle 13 (2016), #13065, 21.4 hr DDT (2016), #12128, 8.7 hr DDT (2014), #10175, 0.4 hr

Selected Telescope • International Time Programme of the Observatories of the Time as Canary Islands, GTC (58 hr), TNG (11 n), WHT (10 n), Co-Investigator INT (10 n), LT (15 n), STELLA (80 h), MERCATOR (15 n), 2016B to 2018A, PI: B. Gaensicke • NTT/ULTRACAM,SOFI, 6 nights, 097.C.0829, 2016A, PI: N. Hallakoun • Chandra, 2016, 40 ks, PI: S. Rappaport • Keck/HIRES, ∼10 nights, 2011 to 2016, PI: M. Jura • Keck/ESI, ∼8 nights, 2015 to 2016, PI: B. Zuckerman • UKIRT/WFCAM, 2014-2016, ∼100 hr, PI: K. Su • LBTI/LMIRCAM, 2016B, 1 night: PI: S. Ertel • Magellan/MIKE, 2015B, 1.5 nights, PI: T. Bergin • Magellan/IMACS, 2015A, 2 nights, PI: T. Bergin • ALMA, Cycle 3, 2015, 3.5 hr, PI: S. Ertel • HST/COS, #12290, #13453, 31 orbits, PI: M. Jura • Spitzer/IRAC, #70055, #80003, #90102, #10032, 47.5 hr, PI: M. Jura

Awards Seal of Excellence, Marie Sklodowska•Curie actions, 2017 Best Talk, ESO Science Day, 2016

S. Xu | Curriculum Vitae 2/6 Best Presentation, Frontiers of Stellar Spectroscopy, Heidelberg, 2015 International Astronomical Union travel grant, 2012 Meticulous Winner, the Mathematical Contest in Modeling consortium for mathematics and its applications, 2009 Excellence Completion of National Undergraduate Innovative Program, Nanjing University, 2008 Renmin Fellowship, Nanjing University, 2007 Service

Departmental or Very Large Telescope / Unit Telescope 2 Science Operation Committee Service Astronomy Graduate Colloquium Coordinator, UCLA, 2012 to 2013

Colloquia Organized Wine & Cheese talk, ESO, 2015 to 2017 Stellar Coffee and Planetary Tea, for ESO & MPA/MPE, 2014 to 2016 Astronomy Journal Club Coordinator, UCLA, 2011 to 2012

Referee for Astrophysical Journal Monthly Notices of the Royal Astronomical Society ESO Director’s Discretionary Time Proposals (Technical Assessment) ALMA Cycle 4 proposal review (Technical Secretary)

Proposal Review Hubble Cycle 25 Review Panel Panel Service Hubble mid-cycle Review Panel GRAVITY Science Verification Proposal Selection Committee Fellow Selection Committee for ESO, Garching NASA Exoplanets Research Program, External Review

Meetings Organized Planetary Systems Beyond The Main Sequence II, Isreal, 2017 (SOC)

Teaching

Teaching Experience Lab Teaching Assistant, Nature of the Universe, Spring 2012 Teaching Assistant, Life in Universe, summer 2012

Students Supervised Nathaniel N. Monson, UCLA Ph.D. student, 2016 to present Na’ama Hallakoun, ESO Ph.D. student, 2015 to 2017 Narges Jamialahmadi, ESO Ph.D. student, 2015 Nivedita Mahesh, UCLA M.S. student, 2014 to 2015 Guochao Sun, UCLA B.S. student, 2013 to 2014 Misaki Nabeshima, UCLA B.S. student, 2012 to 2013 Blake Pantoja, REU student, summer 2013 S. Xu | Curriculum Vitae 3/6 Press & Public Outreach

Press Releases on STScI/NASA/ESA: Hubble finds big brother of Halley’s Comet First-Author Papers ripped apart by white dwarf, 2017 NASA/JPL: Can Planets be Rejuvenated around Dead Stars? 2015 Kunshan Daily: The Quest for the Brightest Star 2015 Physics World: Cold Hydrogen Molecules Found on Hot Stars 2013

Education & Public Talk, Astronomy for non-Astronomers, ESO, 2017 Public Outreach Messenger article, Fellows at ESO, 166, 68, 2016 Volunteer at ESO Open House Day, 2016 Astronomer in Hubble Podcast #95, 2016 Public Talk, Kunshan Middle School, 2015 Host regular shows at UCLA planetarium, 2011 to 2014 Member of UCLA outreach group Astronomy Live!, 2010 to 2014 Vice President of Astronomy Club, Nanjing University, 2008 to 2009 Co-author in Translating Comets: Creators and Destroyers by D. H. Levy into Chinese, 2008

Talks & Colloquia

Invited • Gordon Conference on Origins of Solar Systems, 2017 Talks • Colloquium talk, ASIAA, Taiwan, 2016 • PUC seminar, Pontificia Universidad Catolica de Chile, Santiago, Chile, 2016 • Invited talk, Workshop: From Dust to Planet, Lyon Observatory, France, 2016 • Invited Talk, Michael Jura Memorial Symposium, UCLA, US, 2016 • Star and Planet Formation Seminar, STScI, US, 2016 • Exoplanet Seminar Talk, University of Cambridge, UK, 2016 • Colloquium talk, University of Tuebingen, Germany, 2016 • NOAO flash talk, Arizona, US, 2016 • Informal Discussion, ESO Garching, Germany, 2016 • Colloquium Talk, University of Warwick, UK, 2015 • Colloquium Talk, ETH, Zurich, Switzerland, 2015 • CRAL seminar, Centre de Recherche Astrophysique le Lyon, France, 2015 • Wine & Cheese Talk, ESO, Germany, 2014 • Lunch Talk, Department of Terrestrial Magnetism, Carnegie Institute, US, 2014 • Lunch Talk, Carnegie Observatories, Pasadena, US, 2013 • Lunch Talk, Nanjing University, China, 2013

S. Xu | Curriculum Vitae 4/6 • Lunch talk, National Astronomical Observatories, Beijing, China, 2013 • Invited Talk, American Astronomical Society Meeting #221, Long Beach, US, 2012

Contributed • MIAPP: Protoplanetary Disks and Planet Formation and Evolution, Talks Munich, Germany, 2017 • Science with Hubble and James Webb Space Telescope V, Venice, Italy, 2017 • Planetary Systems Beyond The Main Sequence II, Technion, Israel, 2017 • 20th European White Dwarf Workshop, Warwick, UK, 2016 • Young Solar Systems, Sant Cugat, Spain, 2016 • Frontiers of Stellar Spectroscopy, Heidelberg, Germany, 2015 • Planet Formation and Evolution, Kiel, Germany, 2014 • 19th European White Dwarf Workshop, Montreal, Canada, 2014 • American Astronomical Society Meeting #223, Washington DC, US, 2014 • Project Presentation, Sao Paulo Advanced School of Astrobiology, Brazil, 2011 • STScI: the Delivery of Volatiles & Organics, Baltimore, US, 2011 Refereed Publications

First Author: 10. A dearth of small particles in the transiting material around the white dwarf WD 1145+017 S. Xu, S. Rappaport, & R. v. Lieshout, et al., MNRAS, submitted 9. The Chemical Composition of an Extrasolar Kuiper•Belt•Object S. Xu, B. Zuckerman, P. Dufour, E. D. Young, B. Klein, & M. Jura, 2017, ApJL, 836, L7 8. Evidence for Gas from a Disintegrating Extrasolar Asteroid S. Xu, M. Jura, P. Dufour, & B. Zuckerman, 2016, ApJL, 816, L22 7. An Extreme•AO Search for Giant Planets around a White Dwarf: VLT/SPHERE performance on a faint target GD 50 S. Xu, S. Ertel, Z. Wahhaj, J. Milli, P. Scicluna & G. H.-M. Bertrang, 2015, A&A, 579, L8 6. A Young White Dwarf with an Infrared Excess S. Xu, M. Jura, & B. Pantoja, et al., 2015, ApJL, 806, L5 5. The Drop during Less than 300 Days of A Dusty White Dwarf’s Infrared Luminosity S. Xu, & M. Jura, 2014, ApJL, 792, L39 4. Elemental Compositions of Two Extrasolar Rocky Planetesimals S. Xu, M. Jura, D. Koester, B. Klein, & B. Zuckerman, 2014, ApJ, 783, 79 3. Two Beyond•Primitive Extrasolar Planetesimals S. Xu, M. Jura, B. Klein, D. Koester, & B. Zuckerman, 2013, ApJ, 766, 132

S. Xu | Curriculum Vitae 5/6 2. Discovery of Molecular Hydrogen in White Dwarf Atmospheres S. Xu, M. Jura, D. Koester, B. Klein, & B. Zuckerman, 2013, ApJL, 766, L17 1. Spitzer Observations of White Dwarfs: the Missing Planetary Debris Around DZ Stars S. Xu, & M. Jura, 2012, ApJ, 175, 88 Contributing Author: 13. WD 1145+017: Optical Activity During 2016•2017 and Limits on the X•Ray Flux S. Rappaport, B. L. Gary, A. Vanderburg, & S. Xu, et al., MNRAS in press, arXiv:1709.0819 12. The critical binary star separation for a planetary system origin of white dwarf pollution D. Veras, D., S. Xu, & A. Rebassa-Mansergas, MNRAS in press, arXiv:1708.05391 11. Planetary Systems around White Dwarfs A. Bonsor, & S. Xu, in press, Springer 10. Once in a blue moon: detection of ‘bluing’ during debris transits in the white dwarf WD 1145+017 N. Hallakoun, S. Xu, D. Maoz, et al. 2017, MNRAS, 469, 3213 9. Chemical Abundances in a High•Velocity RR Lyrae Star Near the Bulge C. J. Hansen, R. M. Rich, A. Koch, A., & S. Xu, et al., 2016, A&A, 590, A39 8. Evidence for an Anhydrous Carbonaceous Extrasolar Minor Planet M. Jura, P. Dufour, & S. Xu, et al., 2015, ApJ, 799, 109 7. A Pilot Search for Evidence of Extrasolar Earth•analog Plate Tectonics M. Jura, B. Klein, S. Xu, & E. D. Young, 2014, ApJL, 791, L29 6. 26Al in the Early Solar System: Not so Unusual After All M. Jura, S. Xu, & E. D. Young, 2013, ApJL, 775, L41 5. The Hyades Cluster: Identification of a Planetary System and Escaping White Dwarfs B. Zuckerman, S. Xu, B. Klein, & M. Jura, 2013, ApJ, 770, 140 4. Extrasolar Refractory•Dominated Planetesimals: an Assessment M. Jura, & S. Xu, 2013, AJ, 145, 30 3. Two Extrasolar Asteroids with Low Volatile•Element Mass Fractions M. Jura, S. Xu, B. Klein, D. Koester, & B. Zuckerman, 2012, ApJ, 750, 69 2. Water Fractions in Extrasolar Planetesimals M. Jura, & S. Xu, 2012, AJ, 143, 6 1. The Survival of Water within Extrasolar Minor Planets M. Jura, & S. Xu, 2010, AJ, 140, 1129

S. Xu | Curriculum Vitae 6/6