Showing papers by "Erminia Calabrese published in 2021"
TL;DR: Aghanim et al. as mentioned in this paper used the same data set to derive a 95% upper bound of 0.020 using the principal component analysis (PCA) model and uniform priors on the PCA mode amplitudes.
Abstract: Author(s): Aghanim, N; Akrami, Y; Ashdown, M; Aumont, J; Baccigalupi, C; Ballardini, M; Banday, AJ; Barreiro, RB; Bartolo, N; Basak, S; Battye, R; Benabed, K; Bernard, JP; Bersanelli, M; Bielewicz, P; Bock, JJ; Bond, JR; Borrill, J; Bouchet, FR; Boulanger, F; Bucher, M; Burigana, C; Butler, RC; Calabrese, E; Cardoso, JF; Carron, J; Challinor, A; Chiang, HC; Chluba, J; Colombo, LPL; Combet, C; Contreras, D; Crill, BP; Cuttaia, F; De Bernardis, P; De Zotti, G; Delabrouille, J; Delouis, JM; DI Valentino, E; DIego, JM; Dore, O; Douspis, M; Ducout, A; Dupac, X; Dusini, S; Efstathiou, G; Elsner, F; Enslin, TA; Eriksen, HK; Fantaye, Y; Farhang, M; Fergusson, J; Fernandez-Cobos, R; Finelli, F; Forastieri, F; Frailis, M; Fraisse, AA; Franceschi, E; Frolov, A; Galeotta, S; Galli, S; Ganga, K; Genova-Santos, RT; Gerbino, M; Ghosh, T; Gonzalez-Nuevo, J; Gorski, KM; Gratton, S; Gruppuso, A; Gudmundsson, JE; Hamann, J; Handley, W; Hansen, FK; Herranz, D; Hildebrandt, SR; Hivon, E; Huang, Z; Jaffe, AH; Jones, WC; Karakci, A; Keihanen, E; Keskitalo, R; Kiiveri, K; Kim, J; Kisner, TS | Abstract: In the original version, the bounds given in Eqs. (87a) and (87b) on the contribution to the early-time optical depth, (15,30), contained a numerical error in deriving the 95th percentile from the Monte Carlo samples. The corrected 95% upper bounds are: τ(15,30) l 0:018 (lowE, flat τ(15, 30), FlexKnot), (1) τ(15, 30) l 0:023 (lowE, flat knot, FlexKnot): (2) These bounds are a factor of 3 larger than the originally reported results. Consequently, the new bounds do not significantly improve upon previous results from Planck data presented in Millea a Bouchet (2018) as was stated, but are instead comparable. Equations (1) and (2) give results that are now similar to those of Heinrich a Hu (2021), who used the same Planck 2018 data to derive a 95% upper bound of 0.020 using the principal component analysis (PCA) model and uniform priors on the PCA mode amplitudes.
344 citations
University of Manchester1, City University of New York2, Istanbul Technical University3, New York University4, Heidelberg University5, Niels Bohr Institute6, University of Edinburgh7, University of Bologna8, Academy of Athens9, Sapienza University of Rome10, University of Naples Federico II11, Stanford University12, Institut d'Astrophysique de Paris13, University of Portsmouth14, Cardiff University15, Universidade Federal do Espírito Santo16, University of Michigan17, Asia Pacific Center for Theoretical Physics18, University of New Mexico19, University of Barcelona20, University of St. Thomas (Minnesota)21, Princeton University22, National Autonomous University of Mexico23, California Institute of Technology24, INAF25, University of Chicago26, Michigan Technological University27, Lawrence Berkeley National Laboratory28, University of Cambridge29, Imperial College London30, Ruhr University Bochum31, University of Oxford32, University of Waterloo33, Johns Hopkins University34, University of Pennsylvania35, University of California, Davis36, Birla Institute of Technology and Science37, RWTH Aachen University38, Université libre de Bruxelles39, University of Padua40, Indian Institute of Technology Kharagpur41, Spanish National Research Council42, University of North Carolina at Chapel Hill43, University of Arizona44, University of Oslo45, Jamia Millia Islamia46, University of Southern Denmark47, National Institute for Space Research48, Fermilab49, Presidency University, Kolkata50, Université Paris-Saclay51, University of Montpellier52, University of Szczecin53, Korea Astronomy and Space Science Institute54, University of California, Los Angeles55, University of Paris56, Leiden University57, Swarthmore College58, University of Sheffield59, University of Amsterdam60, United College, Winnipeg61, Liaoning Normal University62
TL;DR: In this article, the authors focus on the 4.4σ tension between the Planck estimate of the Hubble constant H0 and the SH0ES collaboration measurements and discuss how the next decade's experiments will be crucial.
322 citations
University of Manchester1, City University of New York2, Istanbul Technical University3, New York University4, Heidelberg University5, Niels Bohr Institute6, University of Edinburgh7, University of Bologna8, Academy of Athens9, Sapienza University of Rome10, University of Naples Federico II11, Stanford University12, Institut d'Astrophysique de Paris13, University of Portsmouth14, Cardiff University15, Universidade Federal do Espírito Santo16, University of Michigan17, Asia Pacific Center for Theoretical Physics18, University of New Mexico19, University of Barcelona20, Centre national de la recherche scientifique21, Princeton University22, National Autonomous University of Mexico23, Jet Propulsion Laboratory24, INAF25, University of Chicago26, Michigan Technological University27, University of Cambridge28, Imperial College London29, Ruhr University Bochum30, University of Waterloo31, Johns Hopkins University32, University of Pennsylvania33, University of California, Davis34, Birla Institute of Technology and Science35, RWTH Aachen University36, Université libre de Bruxelles37, University of Padua38, Indian Institute of Technology Kharagpur39, Spanish National Research Council40, University of North Carolina at Chapel Hill41, University of Arizona42, University of Oslo43, Jamia Millia Islamia44, National Institute for Space Research45, Fermilab46, Presidency University, Kolkata47, Université Paris-Saclay48, University of Montpellier49, University of Szczecin50, Korea Astronomy and Space Science Institute51, University of California, Los Angeles52, Leiden University53, University of Southern Denmark54, Swarthmore College55, University of Sheffield56, University of Amsterdam57, United College, Winnipeg58, Liaoning Normal University59
TL;DR: In this article, the authors focus on the tension between Planck data and weak lensing measurements and redshift surveys, and discuss the importance of trying to fit multiple cosmological datasets with complete physical models, rather than fitting individual datasets with a few handpicked theoretical parameters.
181 citations
TL;DR: In this article, a catalog of 4195 optically confirmed galaxy clusters detected with signal-to-noise ratio >4 in 13,211 deg2 of sky surveyed by the Atacama Cosmology Telescope (ACT) is presented.
Abstract: We present a catalog of 4195 optically confirmed Sunyaev–Zel’dovich (SZ) selected galaxy clusters detected with signal-to-noise ratio >4 in 13,211 deg2 of sky surveyed by the Atacama Cosmology Telescope (ACT). Cluster candidates were selected by applying a multifrequency matched filter to 98 and 150 GHz maps constructed from ACT observations obtained from 2008 to 2018 and confirmed using deep, wide-area optical surveys. The clusters span the redshift range 0.04 1 clusters, and a total of 868 systems are new discoveries. Assuming an SZ signal versus mass-scaling relation calibrated from X-ray observations, the sample has a 90% completeness mass limit of M500c > 3.8 × 1014 Me, evaluated at z = 0.5, for clusters detected at signal-to-noise ratio >5 in maps filtered at an angular scale of 2 4. The survey has a large overlap with deep optical weak-lensing surveys that are being used to calibrate the SZ signal mass-scaling relation, such as the Dark Energy Survey (4566 deg2), the Hyper Suprime-Cam Subaru Strategic Program (469 deg2), and the Kilo Degree Survey (825 deg2). We highlight some noteworthy objects in the sample, including potentially projected systems, clusters with strong lensing features, clusters with active central galaxies or star formation, and systems of multiple clusters that may be physically associated. The cluster catalog will be a useful resource for future cosmological analyses and studying the evolution of the intracluster medium and galaxies in massive clusters over the past 10 Gyr.
100 citations
University of Manchester1, City University of New York2, Istanbul Technical University3, New York University4, Heidelberg University5, University of Copenhagen6, University of Edinburgh7, University of Bologna8, Academy of Athens9, Sapienza University of Rome10, University of Naples Federico II11, Stanford University12, Institut d'Astrophysique de Paris13, University of Portsmouth14, Cardiff University15, Universidade Federal do Espírito Santo16, University of Michigan17, Asia Pacific Center for Theoretical Physics18, University of New Mexico19, University of Barcelona20, Princeton University21, National Autonomous University of Mexico22, California Institute of Technology23, INAF24, University of Chicago25, Michigan Technological University26, University of Cambridge27, Imperial College London28, Ruhr University Bochum29, University of Waterloo30, Johns Hopkins University31, University of Pennsylvania32, University of California, Davis33, Birla Institute of Technology and Science34, RWTH Aachen University35, Université libre de Bruxelles36, University of Padua37, Indian Institute of Technology Kharagpur38, Spanish National Research Council39, University of North Carolina at Chapel Hill40, University of Arizona41, University of Oslo42, Jamia Millia Islamia43, National Institute for Space Research44, Durban University of Technology45, Fermilab46, Presidency University, Kolkata47, Université Paris-Saclay48, University of Montpellier49, University of Szczecin50, Korea Astronomy and Space Science Institute51, University of California, Los Angeles52, Centre national de la recherche scientifique53, Leiden University54, Swarthmore College55, University of Sheffield56, University of Amsterdam57, United College, Winnipeg58, Liaoning Normal University59
TL;DR: In this paper, the authors present a list of important goals that need to be addressed in the next decade, also taking into account the current discordances present between the different cosmological probes, as the Hubble constant H0 value, the σ8S8 tension, and the anomalies present in the Planck results.
72 citations
Lawrence Berkeley National Laboratory1, University of California, Berkeley2, Cornell University3, National Institute of Standards and Technology4, University of Toronto5, Cardiff University6, University of Pennsylvania7, Princeton University8, Pontifical Catholic University of Chile9, University of Pittsburgh10, Stony Brook University11, Columbia University12, University of KwaZulu-Natal13, Florida State University14, Rutgers University15, Yale University16, University of Chicago17, Perimeter Institute for Theoretical Physics18, European Southern Observatory19, University of Milan20, Haverford College21, Stanford University22, California Institute of Technology23, Pontifical Catholic University of Valparaíso24, Carnegie Mellon University25, National Autonomous University of Mexico26, Goddard Space Flight Center27
TL;DR: Schaan et al. as mentioned in this paper used combined microwave maps from the Atacama Cosmology Telescope DR5 and Planck in combination with the CMASS (mean redshift) to detect the thermal and kinematic Sunyaev-Zel'dovich effects.
Abstract: Author(s): Schaan, E; Ferraro, S; Amodeo, S; Battaglia, N; Aiola, S; Austermann, JE; Beall, JA; Bean, R; Becker, DT; Bond, RJ; Calabrese, E; Calafut, V; Choi, SK; Denison, EV; Devlin, MJ; Duff, SM; Duivenvoorden, AJ; Dunkley, J; Dunner, R; Gallardo, PA; Guan, Y; Han, D; Hill, JC; Hilton, GC; Hilton, M; HloŽek, R; Hubmayr, J; Huffenberger, KM; Hughes, JP; Koopman, BJ; Macinnis, A; McMahon, J; Madhavacheril, MS; Moodley, K; Mroczkowski, T; Naess, S; Nati, F; Newburgh, LB; Niemack, MD; Page, LA; Partridge, B; Salatino, M; Sehgal, N; Schillaci, A; Sifon, C; Smith, KM; Spergel, DN; Staggs, S; Storer, ER; Trac, H; Ullom, JN; Van Lanen, J; Vale, LR; Van Engelen, A; Magana, MV; Vavagiakis, EM; Wollack, EJ; Xu, Z | Abstract: The scattering of cosmic microwave background (CMB) photons off the free-electron gas in galaxies and clusters leaves detectable imprints on high resolution CMB maps: the thermal and kinematic Sunyaev-Zel'dovich effects (tSZ and kSZ respectively). We use combined microwave maps from the Atacama Cosmology Telescope DR5 and Planck in combination with the CMASS (mean redshift ⟨z
69 citations
University of Manchester1, City University of New York2, Istanbul Technical University3, New York University4, Heidelberg University5, Niels Bohr Institute6, University of Edinburgh7, University of Bologna8, Academy of Athens9, Sapienza University of Rome10, University of Naples Federico II11, Stanford University12, Pierre-and-Marie-Curie University13, Istituto Nazionale di Fisica Nucleare14, Cardiff University15, Universidade Federal do Espírito Santo16, University of Michigan17, Asia Pacific Center for Theoretical Physics18, University of New Mexico19, University of Barcelona20, National Autonomous University of Mexico21, Jet Propulsion Laboratory22, University of Chicago23, Michigan Technological University24, University of Cambridge25, Ruhr University Bochum26, Johns Hopkins University27, University of Pennsylvania28, University of California, Davis29, Birla Institute of Technology and Science30, RWTH Aachen University31, Université libre de Bruxelles32, University of Padua33, Indian Institute of Technology Kharagpur34, Spanish National Research Council35, University of North Carolina at Chapel Hill36, University of Arizona37, University of Oslo38, Jamia Millia Islamia39, National Institute for Space Research40, Fermilab41, University of Paris42, University of Montpellier43, University of Szczecin44, Korea Astronomy and Space Science Institute45, University of Southern California46, Centre national de la recherche scientifique47, Leiden University48, Swarthmore College49, University of Sheffield50, University of Amsterdam51, Chinese Academy of Sciences52, United College, Winnipeg53, Liaoning Normal University54
TL;DR: In particular, the Planck Cosmic Microwave Background power spectra, assuming the nominal likelihood, prefer a closed universe at more than 99% confidence level as mentioned in this paper. But this anomaly may be the result of an unresolved systematic error or just a statistical fluctuation.
63 citations
Cornell University1, Lawrence Berkeley National Laboratory2, University of California, Berkeley3, National Institute of Standards and Technology4, University of Toronto5, Cardiff University6, University of Pennsylvania7, Princeton University8, Pontifical Catholic University of Chile9, Johns Hopkins University10, Stony Brook University11, Columbia University12, University of KwaZulu-Natal13, Florida State University14, Rutgers University15, Yale University16, University of Chicago17, Perimeter Institute for Theoretical Physics18, European Southern Observatory19, University of Milan20, Haverford College21, California Institute of Technology22, Pontifical Catholic University of Valparaíso23, Goddard Space Flight Center24
TL;DR: Amodeo et al. as discussed by the authors showed that the thermal and kinematic Sunyaev-Zel'dovich effects (tSZ, kSZ) probe the thermodynamic properties of the circumgalactic and intracluster medium (CGM and ICM) of galaxies, groups, and clusters, since they are proportional to the integrated electron pressure and momentum along the line of sight.
Abstract: Author(s): Amodeo, S; Battaglia, N; Schaan, E; Ferraro, S; Moser, E; Aiola, S; Austermann, JE; Beall, JA; Bean, R; Becker, DT; Bond, RJ; Calabrese, E; Calafut, V; Choi, SK; Denison, EV; Devlin, M; Duff, SM; Duivenvoorden, AJ; Dunkley, J; Dunner, R; Gallardo, PA; Hall, KR; Han, D; Hill, JC; Hilton, GC; Hilton, M; HloŽek, R; Hubmayr, J; Huffenberger, KM; Hughes, JP; Koopman, BJ; Macinnis, A; McMahon, J; Madhavacheril, MS; Moodley, K; Mroczkowski, T; Naess, S; Nati, F; Newburgh, LB; Niemack, MD; Page, LA; Partridge, B; Schillaci, A; Sehgal, N; Sifon, C; Spergel, DN; Staggs, S; Storer, ER; Ullom, JN; Vale, LR; Van Engelen, A; Van Lanen, J; Vavagiakis, EM; Wollack, EJ; Xu, Z | Abstract: The thermal and kinematic Sunyaev-Zel'dovich effects (tSZ, kSZ) probe the thermodynamic properties of the circumgalactic and intracluster medium (CGM and ICM) of galaxies, groups, and clusters, since they are proportional, respectively, to the integrated electron pressure and momentum along the line of sight. We present constraints on the gas thermodynamics of CMASS (constant stellar mass) galaxies in the Baryon Oscillation Spectroscopic Survey using new measurements of the kSZ and tSZ signals obtained in a companion paper [Schaan et al.]. Combining kSZ and tSZ measurements, we measure within our model the amplitude of energy injection ϵM⋆c2, where M⋆ is the stellar mass, to be ϵ=(40±9)×10-6, and the amplitude of the nonthermal pressure profile to be αNthl0.2(2σ), indicating that less than 20% of the total pressure within the virial radius is due to a nonthermal component. We estimate the effects of including baryons in the modeling of weak-lensing galaxy cross-correlation measurements using the best-fit density profile from the kSZ measurement. Our estimate reduces the difference between the original theoretical model and the weak-lensing galaxy cross-correlation measurements in [A. Leauthaud et al., Mon. Not. R. Astron. Soc. 467, 3024 (2017)MNRAA40035-871110.1093/mnras/stx258] by half (50% at most), but does not fully reconcile it. Comparing the kSZ and tSZ measurements to cosmological simulations, we find that they underpredict the CGM pressure and to a lesser extent the CGM density at larger radii with probabilities to exceed ranging from 0.00 to 0.03 and 0.12 to 0.14, for tSZ and kSZ, respectively. This suggests that the energy injected via feedback models in the simulations that we compared against does not sufficiently heat the gas at these radii. We do not find significant disagreement at smaller radii. These measurements provide novel tests of current and future simulations. This work demonstrates the power of joint, high signal-to-noise kSZ and tSZ observations, upon which future cross-correlation studies will improve.
55 citations
Posted Content•
TL;DR: The early dark energy (EDE) scenario aims to increase the value of the Hubble constant (H_0) inferred from cosmic microwave background (CMB) data over that found in $\Lambda$CDM, via the introduction of a new form of energy density in the early universe.
Abstract: The early dark energy (EDE) scenario aims to increase the value of the Hubble constant ($H_0$) inferred from cosmic microwave background (CMB) data over that found in $\Lambda$CDM, via the introduction of a new form of energy density in the early universe. The EDE component briefly accelerates cosmic expansion just prior to recombination, which reduces the physical size of the sound horizon imprinted in the CMB. Previous work has found that non-zero EDE is not preferred by Planck CMB power spectrum data alone, which yield a 95% confidence level (CL) upper limit $f_{\rm EDE} 99.7$% CL: $f_{\rm EDE} = 0.091^{+0.020}_{-0.036}$, with $H_0 = 70.9^{+1.0}_{-2.0}$ km/s/Mpc (both 68% CL). From a model-selection standpoint, we find that EDE is favored over $\Lambda$CDM by these data at roughly $3\sigma$ significance. In contrast, a joint analysis of the full Planck and ACT data yields no evidence for EDE, as previously found for Planck alone. We show that the preference for EDE in ACT alone is driven by its TE and EE power spectrum data. The tight constraint on EDE from Planck alone is driven by its high-$\ell$ TT power spectrum data. Understanding whether these differing constraints are physical in nature, due to systematics, or simply a rare statistical fluctuation is of high priority. The best-fit EDE models to ACT and Planck exhibit coherent differences across a wide range of multipoles in TE and EE, indicating that a powerful test of this scenario is anticipated with near-future data from ACT and other ground-based experiments.
39 citations
Stony Brook University1, York University2, Arizona State University3, University of Cambridge4, Perimeter Institute for Theoretical Physics5, Princeton University6, Cornell University7, National Institute of Standards and Technology8, Cardiff University9, University of Pennsylvania10, Lawrence Berkeley National Laboratory11, University of California, Berkeley12, Pennsylvania State University13, Columbia University14, University of KwaZulu-Natal15, University of Toronto16, Rutgers University17, University of Pittsburgh18, Université Paris-Saclay19, University of Milano-Bicocca20, Haverford College21, California Institute of Technology22, Goddard Space Flight Center23
TL;DR: In this paper, the authors present ΛCDM cosmological parameter constraints obtained from delensed microwave background power spectra for the Atacama Cosmology Telescope (ACT) at 150 and 98 GHz.
Abstract: We present ΛCDM cosmological parameter constraints obtained from delensed microwave background power spectra. Lensing maps from a subset of DR4 data from the Atacama Cosmology Telescope (ACT) are used to undo the lensing effect in ACT spectra observed at 150 and 98 GHz. At 150 GHz, we remove the lensing distortion with an effective efficiency of 30% (TT), 30% (EE), 26% (TE) and 20% (BB); this results in detections of the delensing effect at 8.7σ (TT), 5.1σ (EE), 2.6σ (TE), and 2.4σ (BB) significance. The combination of 150 and 98 GHz TT, EE, and TE delensed spectra is well fit by a standard ΛCDM model. We also measure the shift in best-fit parameters when fitting delensed versus lensed spectra; while this shift does not inform our ability to measure cosmological parameters, it does provide a three-way consistency check among the lensing inferred from the best-fit parameters, the lensing in the CMB power spectrum, and the reconstructed lensing map. This shift is predicted to be zero when fitting with the correct model since both lensed and delensed spectra originate from the same region of sky. Fitting with a ΛCDM model and marginalizing over foregrounds, we find that the shift in cosmological parameters is consistent with zero. Our results show that gravitational lensing of the microwave background is internally consistent within the framework of the standard cosmological model.
29 citations
Posted Content•
TL;DR: In this article, the neutrino mass as a function of redshift was reconstructed from current cosmological data using both standard binned priors and linear spline priors with variable knots.
Abstract: We reconstruct the neutrino mass as a function of redshift, $z$, from current cosmological data using both standard binned priors and linear spline priors with variable knots. Using cosmic microwave background temperature, polarization and lensing data, in combination with distance measurements from baryonic acoustic oscillations and supernovae, we find that the neutrino mass is consistent with $\sum m_
u(z)=$ const. We obtain a larger bound on the neutrino mass at low redshifts coinciding with the onset of dark energy domination, $\sum m_
u(z=0)<1.41$ eV (95% CL). This result can be explained either by the well-known degeneracy between $\sum m_
u$ and $\Omega_\Lambda$ at low redshifts, or by models in which neutrino masses are generated very late in the Universe. We convert our results into cosmological limits for models with post-recombination neutrino decay and find $\sum m_
u <0.19$ eV (95% CL), which is below the sensitivity of the KATRIN experiment. Thus, a neutrino mass discovery by KATRIN would hint towards models predicting both post-recombination neutrino mass generation and subsequent relic neutrino annihilation.
Cornell University1, National Institute of Standards and Technology2, Sapienza University of Rome3, University of Toronto4, Cardiff University5, University of Pennsylvania6, Princeton University7, Pontifical Catholic University of Chile8, University of California, Berkeley9, Lawrence Berkeley National Laboratory10, University of Pittsburgh11, Columbia University12, University of KwaZulu-Natal13, Florida State University14, Rutgers University15, Yale University16, Perimeter Institute for Theoretical Physics17, University of Chicago18, University of Milan19, Haverford College20, California Institute of Technology21, Pontifical Catholic University of Valparaíso22, Arizona State University23, Goddard Space Flight Center24, Massachusetts Institute of Technology25
TL;DR: Calafut et al. as mentioned in this paper presented a 5.4-σ detection of the pairwise kinematic Sunyaev-Zel'dovich (kSZ) effect using Atacama Cosmology Telescope (ACT) and SDSS DR15 CMB observations in combination with Luminous Red Galaxy samples from the Sloan Digital Sky Survey (SDSS) DR15 catalog.
Abstract: Author(s): Calafut, Victoria; Gallardo, Patricio A; Vavagiakis, Eve M; Amodeo, Stefania; Aiola, Simone; Austermann, Jason E; Battaglia, Nicholas; Battistelli, Elia S; Beall, James A; Bean, Rachel; Bond, J Richard; Calabrese, Erminia; Choi, Steve K; Cothard, Nicholas F; Devlin, Mark J; Duell, Cody J; Duff, SM; Duivenvoorden, Adriaan J; Dunkley, Jo; Dunner, Rolando; Ferraro, Simone; Guan, Yilun; Hill, J Colin; Hilton, Matt; Hlozek, Renee; Huber, Zachary B; Hubmayr, Johannes; Huffenberger, Kevin M; Hughes, John P; Koopman, Brian J; Kosowsky, Arthur; Li, Yaqiong; Lokken, Martine; Madhavacheril, Mathew; McMahon, Jeff; Moodley, Kavilan; Naess, Sigurd; Nati, Federico; Newburgh, Laura B; Niemack, Michael D; Page, Lyman; Partridge, Bruce; Schaan, Emmanuel; Schillaci, Alessandro; Sifon, Cristobal; Spergel, David N; Staggs, Suzanne T; Ullom, Joel N; Vale, Leila R; Engelen, Alexander Van; Wollack, Edward J; Xu, Zhilei | Abstract: We present a 5.4$\sigma$ detection of the pairwise kinematic Sunyaev-Zel'dovich (kSZ) effect using Atacama Cosmology Telescope (ACT) and $\it{Planck}$ CMB observations in combination with Luminous Red Galaxy samples from the Sloan Digital Sky Survey (SDSS) DR15 catalog. Results are obtained using three ACT CMB maps: co-added 150 GHz and 98 GHz maps, combining observations from 2008-2018 (ACT DR5), which overlap with SDSS DR15 over 3,700 sq. deg., and a component-separated map using night-time only observations from 2014-2015 (ACT DR4), overlapping with SDSS DR15 over 2,089 sq. deg. Comparisons of the results from these three maps provide consistency checks in relation to potential frequency-dependent foreground contamination. A total of 343,647 galaxies are used as tracers to identify and locate galaxy groups and clusters from which the kSZ signal is extracted using aperture photometry. We consider the impact of various aperture photometry assumptions and covariance estimation methods on the signal extraction. Theoretical predictions of the pairwise velocities are used to obtain best-fit, mass-averaged, optical depth estimates for each of five luminosity-selected tracer samples. A comparison of the kSZ-derived optical depth measurements obtained here to those derived from the thermal SZ effect for the same sample is presented in a companion paper.
University of Oxford1, University of Cambridge2, University of Edinburgh3, Liverpool John Moores University4, Princeton University5, Stanford University6, Polish Academy of Sciences7, Cardiff University8, Cornell University9, University College of Engineering10, University of Pennsylvania11, Ruhr University Bochum12, University of Bonn13, Lawrence Berkeley National Laboratory14, University of California, Berkeley15, Leiden University16, Stony Brook University17, Columbia University18, University of KwaZulu-Natal19, National Institute of Standards and Technology20, Rutgers University21, University College London22, University of Waterloo23, Perimeter Institute for Theoretical Physics24, University of Milan25, Haverford College26, California Institute of Technology27, Pontifical Catholic University of Valparaíso28, University of Groningen29, Goddard Space Flight Center30, Massachusetts Institute of Technology31
TL;DR: In this article, the authors measured the cross-correlation between galaxy weak lensing data from the Kilo Degree Survey (KiDS-1000, DR4) and cosmic microwave background (CMB) lensing from the Atacama Cosmology Telescope (ACT, DR 4) and the Planck Legacy survey.
Abstract: We measure the cross-correlation between galaxy weak lensing data from the Kilo Degree Survey (KiDS-1000, DR4) and cosmic microwave background (CMB) lensing data from the Atacama Cosmology Telescope (ACT, DR4) and the Planck Legacy survey. We use two samples of source galaxies, selected with photometric redshifts, $(0.1
Cornell University1, University of Toronto2, Cardiff University3, University of Pennsylvania4, Princeton University5, Pontifical Catholic University of Chile6, University of Arizona7, University of Pittsburgh8, University of British Columbia9, Columbia University10, University of KwaZulu-Natal11, Florida State University12, Yale University13, Perimeter Institute for Theoretical Physics14, University of Milano-Bicocca15, Haverford College16, Stanford University17, Stony Brook University18, Goddard Space Flight Center19, Massachusetts Institute of Technology20
TL;DR: In this paper, the Atacama Cosmology Telescope has been used to detect three transient millimeter-wave sources using data from the atacama cosmology telescope, two of which are coincident in position with M and K stars and the third is coincident with a G star.
Abstract: We report on the serendipitous discovery of three transient millimeter-wave sources using data from the Atacama Cosmology Telescope. The first, detected at R.A. = 273.8138, decl. = −49.4628 at ~50σ total, brightened from less than 5 mJy to at least 1100 mJy at 150 GHz with an unknown rise time shorter than 13 days, during which the increase from 250 mJy to 1100 mJy took only 8 minutes. Maximum flux was observed on 2019 November 8. The source's spectral index in flux between 90–150 GHz was positive, α = 1.5 ± 0.2. The second, detected at R.A. = 105.1584, decl. = −11.2434 at ~20σ total, brightened from less than 20 mJy to at least 300 mJy at 150 GHz with an unknown rise time shorter than 8 days. Maximum flux was observed on 2019 December 15. Its spectral index was also positive, α = 1.8 ± 0.2. The third, detected at R.A. = 301.9952, decl. = 16.1652 at ~40σ total, brightened from less than 8 mJy to at least 300 mJy at 150 GHz over a day or less but decayed over a few days. Maximum flux was observed on 2018 September 11. Its spectrum was approximately flat, with a spectral index of α = −0.2 ± 0.1. None of the sources were polarized to the limits of these measurements. The two rising-spectrum sources are coincident in position with M and K stars, while the third is coincident with a G star.
Cornell University1, National Institute of Standards and Technology2, Sapienza University of Rome3, University of Toronto4, Cardiff University5, University of Pennsylvania6, Princeton University7, Pontifical Catholic University of Chile8, Lawrence Berkeley National Laboratory9, University of California, Berkeley10, University of Pittsburgh11, Columbia University12, University of KwaZulu-Natal13, Florida State University14, Rutgers University15, Yale University16, Perimeter Institute for Theoretical Physics17, University of Chicago18, University of Milan19, Haverford College20, California Institute of Technology21, Pontifical Catholic University of Valparaíso22, Arizona State University23, Goddard Space Flight Center24, Massachusetts Institute of Technology25
TL;DR: Vavagiakis et al. as mentioned in this paper presented high signal-to-noise measurements (up to 12$\sigma$) of the average thermal Sunyaev-Zel'dovich (tSZ) effect from optically selected galaxy groups and clusters and estimate their baryon content within a 2.1$^\prime$ radius aperture.
Abstract: Author(s): Vavagiakis, Eve M; Gallardo, Patricio A; Calafut, Victoria; Amodeo, Stefania; Aiola, Simone; Austermann, Jason E; Battaglia, Nicholas; Battistelli, Elia S; Beall, James A; Bean, Rachel; Bond, J Richard; Calabrese, Erminia; Choi, Steve K; Cothard, Nicholas F; Devlin, Mark J; Duell, Cody J; Duff, SM; Duivenvoorden, Adriaan J; Dunkley, Jo; Dunner, Rolando; Ferraro, Simone; Guan, Yilun; Hill, J Colin; Hilton, Matt; Hlozek, Renee; Huber, Zachary B; Hubmayr, Johannes; Huffenberger, Kevin M; Hughes, John P; Koopman, Brian J; Kosowsky, Arthur; Li, Yaqiong; Lokken, Martine; Madhavacheril, Mathew; McMahon, Jeff; Moodley, Kavilan; Naess, Sigurd; Nati, Federico; Newburgh, Laura B; Niemack, Michael D; Page, Lyman; Partridge, Bruce; Schaan, Emmanuel; Schillaci, Alessandro; Sifon, Cristobal; Spergel, David N; Staggs, Suzanne T; Ullom, Joel N; Vale, Leila R; Engelen, Alexander Van; Wollack, Edward J; Xu, Zhilei | Abstract: We present high signal-to-noise measurements (up to 12$\sigma$) of the average thermal Sunyaev Zel'dovich (tSZ) effect from optically selected galaxy groups and clusters and estimate their baryon content within a 2.1$^\prime$ radius aperture. Sources from the Sloan Digital Sky Survey (SDSS) Baryon Oscillation Spectroscopic Survey (BOSS) DR15 catalog overlap with 3,700 sq. deg. of sky observed by the Atacama Cosmology Telescope (ACT) from 2008 to 2018 at 150 and 98 GHz (ACT DR5), and 2,089 sq. deg. of internal linear combination component-separated maps combining ACT and $\it{Planck}$ data (ACT DR4). The corresponding optical depths, $\bar{\tau}$, which depend on the baryon content of the halos, are estimated using results from cosmological hydrodynamic simulations assuming an AGN feedback radiative cooling model. We estimate the mean mass of the halos in multiple luminosity bins, and compare the tSZ-based $\bar{\tau}$ estimates to theoretical predictions of the baryon content for a Navarro-Frenk-White profile. We do the same for $\bar{\tau}$ estimates extracted from fits to pairwise baryon momentum measurements of the kinematic Sunyaev-Zel'dovich effect (kSZ) for the same data set obtained in a companion paper. We find that the $\bar{\tau}$ estimates from the tSZ measurements in this work and the kSZ measurements in the companion paper agree within $1\sigma$ for two out of the three disjoint luminosity bins studied, while they differ by 2-3$\sigma$ in the highest luminosity bin. The optical depth estimates account for one third to all of the theoretically predicted baryon content in the halos across luminosity bins. Potential systematic uncertainties are discussed. The tSZ and kSZ measurements provide a step towards empirical Compton-$\bar{y}$-$\bar{\tau}$ relationships to provide new tests of cluster formation and evolution models.
TL;DR: The Atacama Cosmology Telescope (ACT) data are available for public access as discussed by the authors, including temperature and polarization maps that cover nearly half the sky at arcminute resolution in three frequency bands, lensing maps and component-separated maps covering 2,100 deg^2 of sky.
Abstract: Two recent large data releases for the Atacama Cosmology Telescope (ACT), called DR4 and DR5, are available for public access. These data include temperature and polarization maps that cover nearly half the sky at arcminute resolution in three frequency bands; lensing maps and component-separated maps covering ~ 2,100 deg^2 of sky; derived power spectra and cosmological likelihoods; a catalog of over 4,000 galaxy clusters; and supporting ancillary products including beam functions and masks. The data and products are described in a suite of ACT papers; here we provide a summary. In order to facilitate ease of access to these data we present a set of Jupyter IPython notebooks developed to introduce users to DR4, DR5, and the tools needed to analyze these data. The data products (excluding simulations) and the set of notebooks are publicly available on the NASA Legacy Archive for Microwave Background Data Analysis (LAMBDA); simulation products are available on the National Energy Research Scientific Computing Center (NERSC).
Posted Content•
TL;DR: The Simons Observatory (SO) is poised to address many questions in Galactic astrophysics in addition to its principal cosmological goals as discussed by the authors, such as constraining the frequency spectrum of polarized dust emission at a level of 0.01%.
Abstract: Observing in six frequency bands from 27 to 280 GHz over a large sky area, the Simons Observatory (SO) is poised to address many questions in Galactic astrophysics in addition to its principal cosmological goals. In this work, we provide quantitative forecasts on astrophysical parameters of interest for a range of Galactic science cases. We find that SO can: constrain the frequency spectrum of polarized dust emission at a level of $\Delta\beta_d \lesssim 0.01$ and thus test models of dust composition that predict that $\beta_d$ in polarization differs from that measured in total intensity; measure the correlation coefficient between polarized dust and synchrotron emission with a factor of two greater precision than current constraints; exclude the non-existence of exo-Oort clouds at roughly 2.9$\sigma$ if the true fraction is similar to the detection rate of giant planets; map more than 850 molecular clouds with at least 50 independent polarization measurements at 1 pc resolution; detect or place upper limits on the polarization fractions of CO(2-1) emission and anomalous microwave emission at the 0.1% level in select regions; and measure the correlation coefficient between optical starlight polarization and microwave polarized dust emission in $1^\circ$ patches for all lines of sight with $N_{\rm H} \gtrsim 2\times10^{20}$ cm$^{-2}$. The goals and forecasts outlined here provide a roadmap for other microwave polarization experiments to expand their scientific scope via Milky Way astrophysics.
Posted Content•
TL;DR: In this paper, the in-flight angle calibration for the JAXA/ISAS second strategic large class mission, LiteBIRD, and estimate its impact on the measurement of the tensor-to-scalar ratio parameter, r, using simulated data.
Abstract: We present a demonstration of the in-flight polarization angle calibration for the JAXA/ISAS second strategic large class mission, LiteBIRD, and estimate its impact on the measurement of the tensor-to-scalar ratio parameter, r, using simulated data. We generate a set of simulated sky maps with CMB and polarized foreground emission, and inject instrumental noise and polarization angle offsets to the 22 (partially overlapping) LiteBIRD frequency channels. Our in-flight angle calibration relies on nulling the EB cross correlation of the polarized signal in each channel. This calibration step has been carried out by two independent groups with a blind analysis, allowing an accuracy of the order of a few arc-minutes to be reached on the estimate of the angle offsets. Both the corrected and uncorrected multi-frequency maps are propagated through the foreground cleaning step, with the goal of computing clean CMB maps. We employ two component separation algorithms, the Bayesian-Separation of Components and Residuals Estimate Tool (B-SeCRET), and the Needlet Internal Linear Combination (NILC). We find that the recovered CMB maps obtained with algorithms that do not make any assumptions about the foreground properties, such as NILC, are only mildly affected by the angle miscalibration. However, polarization angle offsets strongly bias results obtained with the parametric fitting method. Once the miscalibration angles are corrected by EB nulling prior to the component separation, both component separation algorithms result in an unbiased estimation of the r parameter. While this work is motivated by the conceptual design study for LiteBIRD, its framework can be broadly applied to any CMB polarization experiment. In particular, the combination of simulation plus blind analysis provides a robust forecast by taking into account not only detector sensitivity but also systematic effects.
University of Pittsburgh1, Princeton University2, Cornell University3, Cardiff University4, University of Pennsylvania5, Pontifical Catholic University of Chile6, Lawrence Berkeley National Laboratory7, University of California, Berkeley8, Rutgers University9, Yale University10, Perimeter Institute for Theoretical Physics11, University of Chicago12, University of Milan13, Stanford University14, Stony Brook University15, Pontifical Catholic University of Valparaíso16, Goddard Space Flight Center17, Massachusetts Institute of Technology18
TL;DR: In this article, the Atacama Cosmology Telescope (ACT) was used to obtain arcminute-resolution intensity and polarization maps of the Galactic center made with the ACT at 98, 150, and 224 GHz.
Abstract: We present arcminute-resolution intensity and polarization maps of the Galactic center made with the Atacama Cosmology Telescope (ACT). The maps cover a 32 deg$^2$ field at 98, 150, and 224 GHz with $\vert l\vert\le4^\circ$, $\vert b\vert\le2^\circ$. We combine these data with Planck observations at similar frequencies to create coadded maps with increased sensitivity at large angular scales. With the coadded maps, we are able to resolve many known features of the Central Molecular Zone (CMZ) in both total intensity and polarization. We map the orientation of the plane-of-sky component of the Galactic magnetic field inferred from the polarization angle in the CMZ, finding significant changes in morphology in the three frequency bands as the underlying dominant emission mechanism changes from synchrotron to dust emission. Selected Galactic center sources, including Sgr A*, the Brick molecular cloud (G0.253+0.016), the Mouse pulsar wind nebula (G359.23-0.82), and the Tornado supernova remnant candidate (G357.7-0.1), are examined in detail. These data illustrate the potential for leveraging ground-based Cosmic Microwave Background polarization experiments for Galactic science.
University of Oxford1, Fermilab2, University of Southern California3, University of California, Berkeley4, International School for Advanced Studies5, University of New Mexico6, University of Manchester7, Cardiff University8, University of Geneva9, University of Tokyo10, Institute for the Physics and Mathematics of the Universe11, University of Milano-Bicocca12, Princeton University13, University of Pennsylvania14, University of Paris15, University of California, San Diego16, Istituto Nazionale di Fisica Nucleare17, York University18, Columbia University19, University of Virginia20, Université Paris-Saclay21, Perimeter Institute for Theoretical Physics22, University of Groningen23, Lawrence Berkeley National Laboratory24, Goddard Space Flight Center25, Massachusetts Institute of Technology26
TL;DR: In this paper, the authors quantify the calibration requirements for systematic uncertainties for next-generation ground-based observatories targeting the large-angle B-mode polarization of the Cosmic Microwave Background, with a focus on the Simons Observatory (SO).
Abstract: We quantify the calibration requirements for systematic uncertainties for next-generation ground-based observatories targeting the large-angle B-mode polarization of the Cosmic Microwave Background, with a focus on the Simons Observatory (SO). We explore uncertainties on gain calibration, bandpass center frequencies, and polarization angles, including the frequency variation of the latter across the bandpass. We find that gain calibration and bandpass center frequencies must be known to percent levels or less to avoid biases on the tensor-to-scalar ratio r on the order of Δ r~10-3, in line with previous findings. Polarization angles must be calibrated to the level of a few tenths of a degree, while their frequency variation between the edges of the band must be known to O(10) degrees. Given the tightness of these calibration requirements, we explore the level to which residual uncertainties on these systematics would affect the final constraints on r if included in the data model and marginalized over. We find that the additional parameter freedom does not degrade the final constraints on r significantly, broadening the error bar by O(10%) at most. We validate these results by reanalyzing the latest publicly available data from the collaboration within an extended parameter space covering both cosmological, foreground and systematic parameters. Finally, our results are discussed in light of the instrument design and calibration studies carried out within SO.
Posted Content•
TL;DR: In this article, the Atacama Cosmology Telescope (ACT) observations at 98 GHz, 150 GHz and 229 GHz were used to perform a blind shift-and-stack search for Planet 9.
Abstract: We use Atacama Cosmology Telescope (ACT) observations at 98 GHz (2015--2019), 150 GHz (2013--2019) and 229 GHz (2017--2019) to perform a blind shift-and-stack search for Planet 9. The search explores distances from 300 AU to 2000 AU and velocities up to 6.3 arcmin per year, depending on the distance. For a 5 Earth-mass Planet 9 the detection limit varies from 325 AU to 625 AU, depending on the sky location. For a 10 Earth-mass planet the corresponding range is 425 AU to 775 AU. The search covers the whole 18,000 square degrees of the ACT survey, though a slightly deeper search is performed for the parts of the sky consistent with Planet 9's expected orbital inclination. No significant detections are found, which is used to place limits on the mm-wave flux density of Planet 9 over much of its orbit. Overall we eliminate roughly 17% and 9% of the parameter space for a 5 and 10 Earth-mass Planet 9 respectively. We also provide a list of the 10 strongest candidates from the search for possible follow-up. More generally, we exclude (at 95% confidence) the presence of an unknown Solar system object within our survey area brighter than 4--12 mJy (depending on position) at 150 GHz with current distance $300 \text{ AU} < r < 600 \text{ AU}$ and heliocentric angular velocity $1.5'/\text{yr} < v \cdot \frac{500 \text{ AU}}{r} < 2.3'\text{yr}$, corresponding to low-to-moderate eccentricities. These limits worsen gradually beyond 600 AU, reaching 5--15 mJy by 1500 AU.
Posted Content•
TL;DR: In this paper, the authors reported a significant detection of the hot intergalactic medium in the filamentary bridge connecting the galaxy clusters Abell 399 and Abell 401 using a low-noise, high-resolution map of the thermal Sunyaev-Zeldovich signal from the Atacama Cosmology Telescope (ACT) and Planck satellite.
Abstract: We report a significant detection of the hot intergalactic medium in the filamentary bridge connecting the galaxy clusters Abell 399 and Abell 401. This result is enabled by a low-noise, high-resolution map of the thermal Sunyaev-Zeldovich signal from the Atacama Cosmology Telescope (ACT) and Planck satellite. The ACT data provide the $1.65'$ resolution that allows us to clearly separate the profiles of the clusters, whose centres are separated by $37'$, from the gas associated with the filament. A model that fits for only the two clusters is ruled out compared to one that includes a bridge component at $>5\sigma$. Using a gas temperature determined from Suzaku X-ray data, we infer a total mass of $(3.3\pm0.7)\times10^{14}\,\mathrm{M}_{\odot}$ associated with the filament, comprising about $8\%$ of the entire Abell 399-Abell 401 system. We fit two phenomenological models to the filamentary structure; the favoured model has a width transverse to the axis joining the clusters of ${\sim}1.9\,\mathrm{Mpc}$. When combined with the Suzaku data, we find a gas density of $(0.88\pm0.24)\times10^{-4}\,\mathrm{cm}^{-3}$, considerably lower than previously reported. We show that this can be fully explained by a geometry in which the axis joining Abell 399 and Abell 401 has a large component along the line of sight, such that the distance between the clusters is significantly greater than the $3.2\,\mathrm{Mpc}$ projected separation on the plane of the sky. Finally, we present initial results from higher resolution ($12.7"$ effective) imaging of the bridge with the MUSTANG-2 receiver on the Green Bank Telescope.
University of Chicago1, Princeton University2, Cornell University3, National Institute of Standards and Technology4, University of Toronto5, Cardiff University6, University of California, Berkeley7, University of Cambridge8, University of Pennsylvania9, Lawrence Berkeley National Laboratory10, University of Michigan11, University of Pittsburgh12, Stony Brook University13, Columbia University14, University of KwaZulu-Natal15, Florida State University16, Rutgers University17, Yale University18, Université Paris-Saclay19, Perimeter Institute for Theoretical Physics20, University of Milan21, Stanford University22, California Institute of Technology23, Pontifical Catholic University of Valparaíso24, Arizona State University25, Goddard Space Flight Center26, Massachusetts Institute of Technology27
TL;DR: Mallaby-Kay et al. as discussed by the authors presented a set of Jupyter IPython notebooks developed to introduce users to DR4, DR5, and the tools needed to analyze these data.
Abstract: Author(s): Mallaby-Kay, Maya; Atkins, Zachary; Aiola, Simone; Amodeo, Stefania; Austermann, Jason E; Beall, James A; Becker, Daniel T; Bond, J Richard; Calabrese, Erminia; Chesmore, Grace E; Choi, Steve K; Crowley, Kevin T; Darwish, Omar; Denison, Edwawd V; Devlin, Mark J; Duff, Shannon M; Duivenvoorden, Adriaan J; Dunkley, Jo; Ferraro, Simone; Fichman, Kyra; Gallardo, Patricio A; Golec, Joseph E; Guan, Yilun; Han, Dongwon; Hasselfield, Matthew; Hill, J Colin; Hilton, Gene C; Hilton, Matt; Hlozek, Renee; Hubmayr, Johannes; Huffenberger, Kevin M; Hughes, John P; Koopman, Brian J; Louis, Thibaut; MacInnis, Amanda; Madhavacheril, Mathew S; McMahon, Jeff; Moodley, Kavilan; Naess, Sigurd; Namikawa, Toshiya; Nati, Federico; Newburgh, Laura B; Nibarger, John P; Niemack, Michael D; Page, Lyman A; Salatino, Maria; Schaan, Emmanuel; Schillaci, Alessandro; Sehgal, Neelima; Sherwin, Blake D; Sifon, Cristobal; Simon, Sara; Staggs, Suzanne T; Storer, Emilie R; Ullom, Joel N; Engelen, Alexander Van; Lanen, Jeff Van; Vale, Leila R; Wollack, Edward J; Xu, Zhilei | Abstract: Two recent large data releases for the Atacama Cosmology Telescope (ACT), called DR4 and DR5, are available for public access. These data include temperature and polarization maps that cover nearly half the sky at arcminute resolution in three frequency bands; lensing maps and component-separated maps covering ~ 2,100 deg^2 of sky; derived power spectra and cosmological likelihoods; a catalog of over 4,000 galaxy clusters; and supporting ancillary products including beam functions and masks. The data and products are described in a suite of ACT papers; here we provide a summary. In order to facilitate ease of access to these data we present a set of Jupyter IPython notebooks developed to introduce users to DR4, DR5, and the tools needed to analyze these data. The data products (excluding simulations) and the set of notebooks are publicly available on the NASA Legacy Archive for Microwave Background Data Analysis (LAMBDA); simulation products are available on the National Energy Research Scientific Computing Center (NERSC).
TL;DR: In this paper, the authors proposed a cross-drone configuration for the low frequency telescope (LFT : 34-161 GHz), one of LiteBIRD's onboard telescopes, with a wide field-of-view (FoV) with an aperture of 400 mm in diameter, corresponding to an angular resolution of about 30 arcminutes around 100 GHz.
Abstract: LiteBIRD has been selected as JAXA's strategic large mission in the 2020s, to observe the cosmic microwave background (CMB) $B$-mode polarization over the full sky at large angular scales. The challenges of LiteBIRD are the wide field-of-view (FoV) and broadband capabilities of millimeter-wave polarization measurements, which are derived from the system requirements. The possible paths of stray light increase with a wider FoV and the far sidelobe knowledge of $-56$ dB is a challenging optical requirement. A crossed-Dragone configuration was chosen for the low frequency telescope (LFT : 34--161 GHz), one of LiteBIRD's onboard telescopes. It has a wide field-of-view ($18^\circ \times 9^\circ$) with an aperture of 400 mm in diameter, corresponding to an angular resolution of about 30 arcminutes around 100 GHz. The focal ratio f/3.0 and the crossing angle of the optical axes of 90$^\circ$ are chosen after an extensive study of the stray light. The primary and secondary reflectors have rectangular shapes with serrations to reduce the diffraction pattern from the edges of the mirrors. The reflectors and structure are made of aluminum to proportionally contract from warm down to the operating temperature at $5\,$K. A 1/4 scaled model of the LFT has been developed to validate the wide field-of-view design and to demonstrate the reduced far sidelobes. A polarization modulation unit (PMU), realized with a half-wave plate (HWP) is placed in front of the aperture stop, the entrance pupil of this system. A large focal plane with approximately 1000 AlMn TES detectors and frequency multiplexing SQUID amplifiers is cooled to 100 mK. The lens and sinuous antennas have broadband capability. Performance specifications of the LFT and an outline of the proposed verification plan are presented.
Posted Content•
TL;DR: In this article, a model of the atmosphere as a discrete set of emissive turbulent layers that move with respect to the observer with a horizontal wind velocity was proposed to estimate the aggregate angular motion of atmosphere derived from time-ordered data from the Atacama Cosmology Telescope.
Abstract: Fluctuating atmospheric emission is a dominant source of noise for ground-based millimeter-wave observations of the CMB temperature anisotropy at angular scales $\gtrsim 0.5^{\circ}$. We present a model of the atmosphere as a discrete set of emissive turbulent layers that move with respect to the observer with a horizontal wind velocity. After introducing a statistic derived from the time-lag dependent correlation function for detector pairs in an array, referred to as the pair-lag, we use this model to estimate the aggregate angular motion of the atmosphere derived from time-ordered data from the Atacama Cosmology Telescope (ACT). We find that estimates derived from ACT's CMB observations alone agree with those derived from satellite weather data that additionally include a height-dependent horizontal wind velocity and water vapor density. We also explore the dependence of the measured atmospheric noise spectrum on the relative angle between the wind velocity and the telescope scan direction. In particular, we find that varying the scan velocity changes the noise spectrum in a predictable way. Computing the pair-lag statistic opens up new avenues for understanding how atmospheric fluctuations impact measurements of the CMB anisotropy.
TL;DR: In this paper, the authors provided new constraints on the deviation of CMB temperature evolution from the standard model, where the frequency dependence of the distortion is only independent of the cluster redshift when the evolution of the CMB radiation is adiabatic.
Abstract: The Sunyaev-Zel'dovich (SZ) effect introduces a specific distortion of the blackbody spectrum of the cosmic microwave background (CMB) radiation when it scatters off hot gas in clusters of galaxies. The frequency dependence of the distortion is only independent of the cluster redshift when the evolution of the CMB radiation is adiabatic. Using 370 clusters within the redshift range $0.07\lesssim z\lesssim1.4$ from the largest SZ-selected cluster sample to date from the Atacama Cosmology Telescope, we provide new constraints on the deviation of CMB temperature evolution from the standard model $\alpha=0.017^{+0.029}_{-0.032}$, where $T(z)=T_0(1+z)^{1-\alpha}$. This result is consistent with no deviation from the standard adiabatic model. Combining it with previous, independent datasets we obtain a joint constraint of $\alpha=-0.001\pm0.012$.
University of Pittsburgh1, Princeton University2, Cornell University3, Cardiff University4, University of Pennsylvania5, Pontifical Catholic University of Chile6, Lawrence Berkeley National Laboratory7, University of California, Berkeley8, Rutgers University9, Yale University10, Perimeter Institute for Theoretical Physics11, University of Chicago12, University of Milan13, Stanford University14, Stony Brook University15, Pontifical Catholic University of Valparaíso16, Goddard Space Flight Center17, Massachusetts Institute of Technology18
TL;DR: In this paper, the Atacama Cosmology Telescope (ACT) was used to obtain arcminute-resolution intensity and polarization maps of the Galactic center made with the ACT at 98, 150, and 224 GHz.
Abstract: We present arcminute-resolution intensity and polarization maps of the Galactic center made with the Atacama Cosmology Telescope (ACT). The maps cover a 32 deg$^2$ field at 98, 150, and 224 GHz with $\vert l\vert\le4^\circ$, $\vert b\vert\le2^\circ$. We combine these data with Planck observations at similar frequencies to create coadded maps with increased sensitivity at large angular scales. With the coadded maps, we are able to resolve many known features of the Central Molecular Zone (CMZ) in both total intensity and polarization. We map the orientation of the plane-of-sky component of the Galactic magnetic field inferred from the polarization angle in the CMZ, finding significant changes in morphology in the three frequency bands as the underlying dominant emission mechanism changes from synchrotron to dust emission. Selected Galactic center sources, including Sgr A*, the Brick molecular cloud (G0.253+0.016), the Mouse pulsar wind nebula (G359.23-0.82), and the Tornado supernova remnant candidate (G357.7-0.1), are examined in detail. These data illustrate the potential for leveraging ground-based Cosmic Microwave Background polarization experiments for Galactic science.
Johns Hopkins University1, University of Toronto2, Cornell University3, Sapienza University of Rome4, Cardiff University5, University of Pennsylvania6, Princeton University7, Lawrence Berkeley National Laboratory8, University of California, Berkeley9, University of Southern California10, University of Pittsburgh11, University of British Columbia12, University of KwaZulu-Natal13, York University14, University of Milano-Bicocca15, Haverford College16, Stanford University17, California Institute of Technology18, Stony Brook University19, Pontifical Catholic University of Valparaíso20, Arizona State University21, Goddard Space Flight Center22, Massachusetts Institute of Technology23
Posted Content•
TL;DR: Alonso et al. as discussed by the authors proposed a cross-survey work that homogenizes these efforts, exchanges information from numerical simulations, and coordinates details in the modeling of astrophysical and observational systematics of the corresponding datasets.
Abstract: Author(s): Alonso, David; Calabrese, Erminia; Eifler, Tim; Fabbian, Giulio; Ferraro, Simone; Gawiser, Eric; Hill, J Colin; Krause, Elisabeth; Madhavacheril, Mathew; Slosar, Anže; Spergel, David N | Abstract: The tightest and most robust cosmological results of the next decade will be achieved by bringing together multiple surveys of the Universe. This endeavor has to happen across multiple layers of the data processing and analysis, e.g., enhancements are expected from combining Euclid, Rubin, and Roman (as well as other surveys) not only at the level of joint processing and catalog combination, but also during the post-catalog parts of the analysis such as the cosmological inference process. While every experiment builds their own analysis and inference framework and creates their own set of simulations, cross-survey work that homogenizes these efforts, exchanges information from numerical simulations, and coordinates details in the modeling of astrophysical and observational systematics of the corresponding datasets is crucial.