A Constraint on Primordial B-modes from the First Flight of the Spider Balloon-borne Telescope

Journal Article · Mon Mar 14 00:00:00 UTC 2022 · The Astrophysical Journal

DOI: https://doi.org/10.3847/1538-4357/ac20df · OSTI ID:1833302

Ade, P. R. ; Amiri, M.; Benton, S. J. ; Bergman, A. S.; Bihary, R.; Bock, J. J.; Bond, J. R. ; Bonetti, J. A.; Bryan, S. A.; Chiang, H. C. ; Contaldi, C. R. ; Doré, O. ; Duivenvoorden, A. J. ; Eriksen, H. K.; Farhang, M.; Filippini, J. P. ; Fraisse, A. A.; Freese, K.; Galloway, M.; Gambrel, A. E. ; Gandilo, N. N.; Ganga, K. ; Gualtieri, R. ; Gudmundsson, J. E. ; Halpern, M. ; Hartley, J.; Hasselfield, M.; Hilton, G.; Holmes, W.; Hristov, V. V.; Huang, Z.; Irwin, K. D.; Jones, W. C. ; Karakci, A.; Kuo, C. L.; Kermish, Z. D.; Leung, J. S.-Y. ; Li, S. ; Mak, D. Y.; Mason, P. V.; Megerian, K.; Moncelsi, L. ; Morford, T. A.; Nagy, J. M. ; Netterfield, C. B.; Nolta, M.; O’Brient, R.; Osherson, B.; Padilla, I. L. ; Racine, B.; Rahlin, A. S. ; Reintsema, C.; Ruhl, J. E.; Runyan, M. C.; Ruud, T. M. ; Shariff, J. A.; Shaw, E. C.; Shiu, C.; Soler, J. D. ; Song, X.; Trangsrud, A.; Tucker, C.; Tucker, R. S.; Turner, A. D.; van der List, J. F.; Weber, A. C.; Wehus, I. K. ; Wen, S.; Wiebe, D. V.; Young, E. Y.

We present the first linear polarization measurements from the 2015 long-duration balloon flight of Spider, which is an experiment that is designed to map the polarization of the cosmic microwave background (CMB) on degree angular scales. The results from these measurements include maps and angular power spectra from observations of 4.8% of the sky at 95 and 150 GHz, along with the results of internal consistency tests on these data. While the polarized CMB anisotropy from primordial density perturbations is the dominant signal in this region of sky, Galactic dust emission is also detected with high significance. Galactic synchrotron emission is found to be negligible in the Spider bands. We employ two independent foreground-removal techniques to explore the sensitivity of the cosmological result to the assumptions made by each. The primary method uses a dust template derived from Planck data to subtract the Galactic dust signal. A second approach, which constitutes a joint analysis of Spider and Planck data in the harmonic domain, assumes a modified-blackbody model for the spectral energy distribution of the dust with no constraint on its spatial morphology. Using a likelihood that jointly samples the template amplitude and r parameter space, we derive 95% upper limits on the primordial tensor-to-scalar ratio from Feldman–Cousins and Bayesian constructions, finding r < 0.11 and r < 0.19, respectively. Roughly half the uncertainty in r derives from noise associated with the template subtraction. New data at 280 GHz from Spider's second flight will complement the Planck polarization maps, providing powerful measurements of the polarized Galactic dust emission.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL (United States); Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES); USDOE Office of Science (SC), High Energy Physics (HEP)
• Contributing Organization: SPIDER Collaboration
• Grant/Contract Number: AC02-07CH11359; AC02-76SF00515
• OSTI ID: 1833302
• Report Number(s): FERMILAB-PUB-21-566-PPD; arXiv:2103.13334; oai:inspirehep.net:1853283
• Journal Information: The Astrophysical Journal, Journal Name: The Astrophysical Journal Journal Issue: 2 Vol. 927; ISSN 0004-637X
• Publisher: IOP PublishingCopyright Statement
• Country of Publication: United States
• Language: English