Asteroid Measurements at Millimeter Wavelengths with the South Pole Telescope

Journal Article · 13 September 2022 · The Astrophysical Journal

DOI: https://doi.org/10.3847/1538-4357/ac89ec · OSTI ID:1893728

Chichura, P. M.  ^[1]; Foster, A. ; Patel, C.; Ossa-Jaen, N.; Ade, P. R.; Ahmed, Z.; Anderson, A. J.; Archipley, M. ; Austermann, J. E.; Avva, J. S.; Balkenhol, L.; Barry, P. S.; Thakur, R. Basu; Beall, J. A.; Benabed, K.; Bender, A. N.; Benson, B. A. ; Bianchini, F. ; Bleem, L. E. ; Bouchet, F. R. ; Bryant, L.; Byrum, K.; Carlstrom, J. E.; Carter, F. W.; Cecil, T. W.; Chang, C. L.; Chaubal, P.; Chen, G.; Chiang, H. C.; Cho, H. -M.; Chou, T-L; Citron, R.; Cliche, J. -F. ; Crawford, T. M. ; Crites, A. T.; Cukierman, A.; Daley, C. M.; Denison, E. V.; Dibert, K.; Ding, J.; Dobbs, M. A. ; Dutcher, D.; Everett, W. ; Feng, C.; Ferguson, K. R.; Fu, J.; Galli, S.; Gallicchio, J.; Gambrel, A. E.; Gardner, R. W.; George, E. M.; Goeckner-Wald, N.; Gualtieri, R.; Guns, S. ; Gupta, N.; Guyser, R.; Haan, T. de; Halverson, N. W.; Harke-Hosemann, A. H.; Harrington, N. L.; Henning, J. W.; Hilton, G. C.; Hivon, E. ; Holder, G. P. ; Holzapfel, W. L.; Hood, J. C.; Howe, D.; Hrubes, J. D.; Huang, N.; Hubmayr, J.; Irwin, K. D.; Jeong, O. B.; Jonas, M.; Jones, A.; Khaire, T. S.; Knox, L.; Kofman, A. M.; Korman, M.; Kubik, D. L.; Kuhlmann, S.; Kuo, C. -L.; Lee, A. T.; Leitch, E. M.; Li, D.; Lowitz, A.; Lu, C.; Marrone, D. P.; McMahon, J. J.; Meyer, S. S.; Michalik, D.; Millea, M. ; Mocanu, L. M.; Montgomery, J.; Moran, C. Corbett; Nadolski, A.; Natoli, T.; Nguyen, H.; Nibarger, J. P.; Noble, G.; Novosad, V.; Omori, Y.; Padin, S.; Pan, Z.; Paschos, P.; Patil, S. ; Pearson, J.; Phadke, K. A. ; Posada, C. M. ; Prabhu, K.; Pryke, C.; Quan, W.; Rahlin, A.; Reichardt, C. L. ; Riebel, D.; Riedel, B. ; Rouble, M.; Ruhl, J. E.; Saliwanchik, B. R.; Sayre, J. T.; Schaffer, K. K.; Schiappucci, E.; Shirokoff, E.; Sievers, C.; Smecher, G. ; Sobrin, J. A. ; Springmann, A. ; Stark, A. A.; Stephen, J.; Story, K. T.; Suzuki, A.; Tandoi, C.; Thompson, K. L.; Thorne, B.; Tucker, C.; Umilta, C.; Vale, L. R.; Veach, T.; Vieira, J. D.; Wang, G.; Whitehorn, N. ; Wu, W. K. ; Yefremenko, V.; Yoon, K. W.; Young, M. R.

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1. Univ. of Chicago, IL (United States); SPT Collaboration et al.

We present the first measurements of asteroids in millimeter wavelength data from the South Pole Telescope (SPT), which is used primarily to study the cosmic microwave background (CMB). We analyze maps of two similar to 270 deg(2) sky regions near the ecliptic plane, each observed with the SPTpol camera similar to 100 times over 1 month. We subtract the mean of all maps of a given field, removing static sky signal, and then average the mean-subtracted maps at known asteroid locations. We detect three asteroids-(324) Bamberga, (13) Egeria, and (22) Kalliope-with signal-to-noise ratios (S/N) of 11.2, 10.4, and 6.1, respectively, at 2.0 mm (150 GHz); we also detect (324) Bamberga with an S/N of 4.1 at 3.2 mm (95 GHz). We place constraints on these asteroids' effective emissivities, brightness temperatures, and light-curve modulation amplitude. Our flux density measurements of (324) Bamberga and (13) Egeria roughly agree with predictions, while our measurements of (22) Kalliope suggest lower flux, corresponding to effective emissivities of 0.64 +/- 0.11 at 2.0 and < 0.47 at 3.2 mm. We predict the asteroids detectable in other SPT data sets and find good agreement with detections of (772) Tanete and (1093) Freda in recent data from the SPT-3G camera, which has similar to 10x the mapping speed of SPTpol. This work is the first focused analysis of asteroids in data from CMB surveys, and it demonstrates we can repurpose historic and future data sets for asteroid studies. Future SPT measurements can help constrain the distribution of surface properties over a larger asteroid population.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), High Energy Physics (HEP); National Science Foundation (NSF)
• Contributing Organization: SPT Collaboration
• Grant/Contract Number: AC02-07CH11359; PLR-1248097; OPP-1852617; PHY-1125897; AC02-06CH11357
• OSTI ID: 1893728
• Alternate ID(s): OSTI ID: 1960018
• Report Number(s): FERMILAB-PUB-22-769-PPD; arXiv:2202.01406; oai:inspirehep.net:2167221; TRN: US2310224
• Journal Information: The Astrophysical Journal, Vol. 936, Issue 2; ISSN 0004-637X
• Publisher: IOP PublishingCopyright Statement
• Country of Publication: United States
• Language: English