Simultaneous Millimeter-wave, Gamma-Ray, and Optical Monitoring of the Blazar PKS 2326-502 during a Flaring State

Journal Article · Fri Mar 10 00:00:00 EST 2023 · The Astrophysical Journal. Letters

DOI:https://doi.org/10.3847/2041-8213/acbf45· OSTI ID:1969358

Hood II, J. C.  ^[1]; Simpson, A. ^[2]; McDaniel, A.  ^[3]; Foster, A.  ^[4]; Ade, P. A. R.  ^[5]; Ajello, M.  ^[3]; Anderson, A. J. ^[6]; Austermann, J. E.  ^[7]; Beall, J. A.  ^[8]; Bender, A. N.  ^[9]; Benson, B. A.  ^[10]; Bianchini, F.  ^[11]; Bleem, L. E.  ^[9]; Carlstrom, J. E.  ^[9]; Chang, C. L. ^[9]; Chaubal, P. ^[11]; Chiang, H. C. ^[12]; Chou, T-L ^[13]; Citron, R. ^[13]; Moran, C. Corbett ^[14] ; Crawford, T. M.  ^[13]; Crites, A. T. ^[15]; de Haan, T. ^[16]; Dobbs, M. A.  ^[17]; Everett, W.  ^[18]; Gallicchio, J. ^[19]; George, E. M.  ^[20]; Gupta, N.  ^[21]; Halverson, N. W. ^[18]; Hilton, G. C. ^[8]; Holder, G. P.  ^[22]; Holzapfel, W. L. ^[23]; Hrubes, J. D. ^[13]; Huang, N. ^[23]; Hubmayr, J. ^[8]; Irwin, K. D. ^[24]; Knox, L. ^[25]; Lee, A. T.  ^[26]; Li, D. ^[27]; Lowitz, A. ^[13]; Madejski, G. ^[28]; Malkan, M.  ^[29]; McMahon, J. J. ^[30]; Meyer, S. S. ^[30]; Montgomery, J. ^[31]; Natoli, T. ^[13]; Nibarger, J. P. ^[8]; Noble, G. ^[31]; Novosad, V. ^[32]; Omori, Y. ^[33]; Padin, S. ^[34]; Patil, S.  ^[11]; Pryke, C.  ^[35]; Reichardt, C. L.  ^[11]; Ruhl, J. E. ^[4]; Saliwanchik, B. R. ^[36]; Schaffer, K. K. ^[37]; Sievers, C. ^[13]; Smecher, G.  ^[38]; Stark, A. A.  ^[39]; Tucker, C. ^[5]; Veach, T. ^[40]; Vieira, J. D.  ^[41]; Wang, G. ^[32]; Whitehorn, N.  ^[42]; Wu, W. L. K.  ^[43]; Yefremenko, V. ^[32]; Zebrowski, J. A. ^[23]; Zhang, L.  ^[44]

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1. Univ. of Chicago, IL (United States); Vanderbilt Univ., Nashville, TN (United States)
2. Rensselaer Polytechnic Inst., Troy, NY (United States)
3. Clemson Univ., SC (United States)
4. Case Western Reserve Univ., Cleveland, OH (United States)
5. Cardiff Univ., Wales (United Kingdom)
6. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
7. National Inst. of Standards and Technology (NIST), Boulder, CO (United States); Univ. of Colorado, Boulder, CO (United States)
8. National Inst. of Standards and Technology (NIST), Boulder, CO (United States)
9. Univ. of Chicago, IL (United States); Argonne National Lab. (ANL), Argonne, IL (United States)
10. Univ. of Chicago, IL (United States); Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
11. Univ. of Melbourne, Parkville, VIC (Australia)
12. McGill Univ., Montreal, QC (Canada); University of KwaZulu-Natal, Durban (South Africa)
13. Univ. of Chicago, IL (United States)
14. California Institute of Technology (CalTech), Pasadena, CA (United States)
15. Univ. of Chicago, IL (United States); Univ. of Toronto, ON (Canada)
16. High Energy Accelerator Research Organization (KEK), Tsukuba (Japan)
17. McGill Univ., Montreal, QC (Canada); Canadian Institute for Advanced Research (CIFAR), Toronto, ON (Canada)
18. Univ. of Colorado, Boulder, CO (United States)
19. Univ. of Chicago, IL (United States); Harvey Mudd College, Claremont, CA (United States)
20. European Southern Observatory, München (Germany); Univ. of California, Berkeley, CA (United States)
21. Commonwealth Scientific and Industrial Research Organisation (CSIRO) Space & Astronomy, Bentleu, WA (Australia)
22. Canadian Institute for Advanced Research (CIFAR), Toronto, ON (Canada); Univ. of Illinois at Urbana-Champaign, IL (United States)
23. Univ. of California, Berkeley, CA (United States)
24. SLAC National Accelerator Lab., Menlo Park, CA (United States); Stanford Univ., CA (United States)
25. Univ. of California, Davis, CA (United States)
26. Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
27. National Inst. of Standards and Technology (NIST), Boulder, CO (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States)
28. SLAC National Accelerator Lab., Menlo Park, CA (United States)
29. Univ. of California, Los Angeles, CA (United States)
30. Univ. of Chicago, IL (United States); Univ. of Melbourne, Parkville, VIC (Australia)
31. McGill Univ., Montreal, QC (Canada)
32. Argonne National Lab. (ANL), Argonne, IL (United States)
33. Stanford Univ., CA (United States)
34. Univ. of Chicago, IL (United States); California Institute of Technology (CalTech), Pasadena, CA (United States)
35. Univ. of Minnesota, Minneapolis, MN (United States)
36. Case Western Reserve Univ., Cleveland, OH (United States); Yale Univ., New Haven, CT (United States)
37. Univ. of Chicago, IL (United States); School of the Art Institute of Chicago, Chicago, IL (United States)
38. McGill Univ., Montreal, QC (Canada); Three-Speed Logic, Inc., Victoria, BC (Canada)
39. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States)
40. Southwest Research Institute, San Antonio, TX (United States)
41. Univ. of Illinois at Urbana-Champaign, IL (United States). National Center for Supercomputing Applications (NCSA)
42. Univ. of California, Santa Barbara, CA (United States)
43. Univ. of Chicago, IL (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States)
44. Univ. of California, Santa Barbara, CA (United States); Univ. of Illinois at Urbana-Champaign, IL (United States)

Including millimeter-wave data in multiwavelength studies of the variability of active galactic nuclei (AGN) can provide insights into AGN physics that are not easily accessible at other wavelengths. We demonstrate in this work the potential of cosmic microwave background (CMB) telescopes to provide long-term, high-cadence millimeter-wave AGN monitoring over large fractions of sky. We report on a pilot study using data from the SPTpol instrument on the South Pole Telescope (SPT), which was designed to observe the CMB at arcminute and larger angular scales. Between 2013 and 2016, SPTpol was used primarily to observe a single 500 deg2 field, covering the entire field several times per day with detectors sensitive to radiation in bands centered at 95 and 150 GHz. We use SPT 150 GHz observations to create AGN light curves, and we compare these millimeter-wave light curves to those at other wavelengths, in particular γ-ray and optical. In this Letter, we focus on a single source, PKS 2326-502, which has extensive, day-timescale monitoring data in gamma-ray, optical, and now millimeter-wave between 2013 and 2016. We find PKS 2326-502 to be in a flaring state in the first 2 yr of this monitoring, and we present a search for evidence of correlated variability between millimeter-wave, optical R-band, and γ-ray observations. This pilot study is paving the way for AGN monitoring with current and upcoming CMB experiments such as SPT-3G, Simons Observatory, and CMB-S4, including multiwavelength studies with facilities such as Vera C. Rubin Observatories Large Synoptic Survey Telescope.

• 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 Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: National Science Foundation (NSF); USDOE Office of Science (SC), High Energy Physics (HEP)
• Contributing Organization: SPT
• Grant/Contract Number: AC02-06CH11357; OPP-1852617; OPP-2147371; OPP-2219065; AC02-07CH11359
• OSTI ID: 1969358
• Alternate ID(s): OSTI ID: 1960275
• Report Number(s): FERMILAB-PUB-23-100-PPD; arXiv:2302.14749; 181285; TRN: US2313406
• Journal Information: The Astrophysical Journal. Letters, Vol. 945, Issue 2; ISSN 2041-8205
• Publisher: IOP Publishing
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
AGN
Gamma-ray source
Millimeter astronomy
Active galactic nuclei
Blazars
Gamma-ray astronomy