A Deep Search for Emission From" Rock Comet"(3200) Phaethon at 1 AU
Draft version November 23, 2020 Typeset using LATEX preprint style in AASTeX63 A Deep Search for Emission From \Rock Comet" (3200) Phaethon At 1 AU Quanzhi Ye (叶泉志),1 Matthew M. Knight,2, 1 Michael S. P. Kelley,1 Nicholas A. Moskovitz,3 Annika Gustafsson,4 and David Schleicher3 1Department of Astronomy, University of Maryland, College Park, MD 20742, USA 2Department of Physics, United States Naval Academy, 572C Holloway Rd, Annapolis, MD 21402, USA 3Lowell Observatory, 1400 W Mars Hill Road, Flagstaff, AZ 86001, USA 4Department of Astronomy and Planetary Science, P.O. Box 6010, Northern Arizona University, Flagstaff, AZ 86011, USA (Received -; Revised -; Accepted -) Submitted to PSJ ABSTRACT We present a deep imaging and spectroscopic search for emission from (3200) Phaethon, a large near-Earth asteroid that appears to be the parent of the strong Geminid meteoroid stream, using the 4.3 m Lowell Discovery Telescope. Observations were conducted on 2017 December 14{18 when Phaethon passed only 0.07 au from the Earth. We determine the 3σ upper level of dust and CN production rates to be 0.007{0.2 kg s−1 and 2:3 1022 molecule s−1 through narrowband imaging. A search × in broadband images taken through the SDSS r' filter shows no 100-m-class fragments in Phaethon's vicinity. A deeper, but star-contaminated search also shows no sign of fragments down to 15 m. Optical spectroscopy of Phaethon and comet C/2017 O1 (ASASSN) as comparison confirms the absence of cometary emission lines from 24 25 −1 Phaethon and yields 3σ upper levels of CN, C2 and C3 of 10 {10 molecule s , 2 orders of magnitude higher than the CN constraint placed∼ by narrowband imaging, due to the much narrower on-sky aperture of the spectrographic slit.
[Show full text]