Browsing by Author "Choi, Steve K."

Now showing 1 - 5 of 5
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    Atacama Cosmology Telescope: Constraints on cosmic birefringence
    (AMER PHYSICAL SOC, 2020) Namikawa, Toshiya; Guan, Yilun; Darwish, Omar; Sherwin, Blake D.; Aiola, Simone; Battaglia, Nicholas; Beall, James A.; Becker, Daniel T.; Bond, J. Richard; Calabrese, Erminia; Chesmore, Grace E.; Choi, Steve K.; Devlin, Mark J.; Dunkley, Joanna; Dunner, Rolando; Fox, Anna E.; Gallardo, Patricio A.; Gluscevic, Vera; Han, Dongwon; Hasselfield, Matthew; Hilton, Gene C.; Hincks, Adam D.; Hlozek, Renee; Hubmayr, Johannes; Huffenberger, Kevin; Hughes, John P.; Koopman, Brian J.; Kosowsky, Arthur; Louis, Thibaut; Lungu, Marius; MacInnis, Amanda; Madhavacheril, Mathew S.; Mallaby Kay, Maya; Maurin, Loic; McMahon, Jeffrey; Moodley, Kavilan; Naess, Sigurd; Nati, Federico; Newburgh, Laura B.; Nibarger, John P.; Niemack, Michael D.; Page, Lyman A.; Qu, Frank J.; Robertson, Naomi; Schillaci, Alessandro; Sehgal, Neelima; Sifon, Cristobal; Simon, Sara M.; Spergel, David N.; Staggs, Suzanne T.; Storer, Emilie R.; van Engelen, Alexander; van Lanen, Jeff; Wollack, Edward J.
    We present new constraints on anisotropic birefringence of the cosmic microwave background polarization using two seasons of data from the Atacama Cosmology Telescope covering 456 square degrees of sky. The birefringence power spectrum, measured using a curved-sky quadratic estimator, is consistent with zero. Our results provide the tightest current constraint on birefringence over a range of angular scales between 5 arc minutes and 9 degrees. We improve previous upper limits on the amplitude of a scale-invariant birefringence power spectrum by a factor of between 2 and 3. Assuming a nearly massless axion field during inflation, our result is equivalent to a 2 sigma upper limit on the Chern-Simons coupling constant between axions and photons of g(alpha gamma) < 4.0 x 10(-2)/H-I, where H-I is the inflationary Hubble scale.
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    Non-gaussianity of secondary anisotropies from ACTPol and Planck
    (2018) Coulton, William R.; Aiola, Simone; Battaglia, Nicholas; Calabrese, Erminia; Choi, Steve K.; Devlin, Mark J.; Gallardo, Patricio A.; Colin Hill, J.; Hincks, Adam D.; Maurin, Loïc Benjamin
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    Results from the Atacama B-mode search (ABS) experiment
    (2018) Kusaka, Akito; Appel, John; Essinger Hileman, Thomas; Beall, James A.; Campusano, Luis E.; Mei Cho, Hsiao; Choi, Steve K.; Crowley, Kevin; Fowler, Joseph W.; Gallardo, Patricio
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    The Atacama Cosmology Telescope : The Two-season ACTPol Sunyaev-Zel'dovich Effect Selected Cluster Catalog
    (2019) Hilton, Matt; Hasselfield, Matthew; Sifón, Cristóbal; Battaglia, Nicholas; Aiola, Simone; Bharadwaj, V.; Richard Bond, J.; Choi, Steve K.; Dunner Planella, Rolando; Maurin, Loïc Benjamin
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    The atacama cosmology telescope : The two-season ACTPol sunyaev-Zel'dovich effect selected cluster catalog
    (2018) Hilton, Matt; Hasselfield, Matthew; Sifón, Cristóbal; Battaglia, Nicholas; Aiola, Simone; Bharadwaj, V.; Bond, J.Richard,; Choi, Steve K.; Dünner Planella, Rolando; Maurin, Loïc Benjamin