The Atacama Cosmology Telescope: Two-Season ACTPol Spectra and Parameters
astro-ph.CO
/ Authors
Thibaut Louis, Emily Grace, Matthew Hasselfield, Marius Lungu, Loïc Maurin, Graeme E. Addison, Peter A. R. Ade, Simone Aiola, Rupert Allison, Mandana Amiri
and 73 more authors
Elio Angile, Nicholas Battaglia, James A. Beall, Francesco de Bernardis, J. Richard Bond, Joe Britton, Erminia Calabrese, Hsiao-mei Cho, Steve K. Choi, Kevin Coughlin, Devin Crichton, Kevin Crowley, Rahul Datta, Mark J. Devlin, Simon R. Dicker, Joanna Dunkley, Rolando Dünner, Simone Ferraro, Anna E. Fox, Patricio Gallardo, Megan Gralla, Mark Halpern, Shawn Henderson
/ Abstract
We present the temperature and polarization angular power spectra measured by the Atacama Cosmology Telescope Polarimeter (ACTPol). We analyze night-time data collected during 2013-14 using two detector arrays at 149 GHz, from 548 deg$^2$ of sky on the celestial equator. We use these spectra, and the spectra measured with the MBAC camera on ACT from 2008-10, in combination with Planck and WMAP data to estimate cosmological parameters from the temperature, polarization, and temperature-polarization cross-correlations. We find the new ACTPol data to be consistent with the LCDM model. The ACTPol temperature-polarization cross-spectrum now provides stronger constraints on multiple parameters than the ACTPol temperature spectrum, including the baryon density, the acoustic peak angular scale, and the derived Hubble constant. Adding the new data to planck temperature data tightens the limits on damping tail parameters, for example reducing the joint uncertainty on the number of neutrino species and the primordial helium fraction by 20%.