BibTex format
@article{Abril-Cabezas:2026:04/051,
author = {Abril-Cabezas, I and Challinor, A and Clarke, P and Coulton, W and Embil, Villagra C and Fergusson, J and Legrand, L and McCarthy, F and Namikawa, T and Sailer, N and Shellard, P and Sherwin, B and Suman, P and Zubeldia, I and Bolliet, B and Challinor, A and Clarke, P and Coulton, W and Fergusson, J and Hertig, E and Kusiak, A and Legrand, L and McCarthy, F and Namikawa, T and Sherwin, B and Adachi, S and Adachi, S and Ashton, P and Chinone, Y and Jost, B and Katayama, N and Kusaka, A and Liu, J and Matsumura, T and Namikawa, T and Sakurai, Y and Tajima, O and Takakura, S and Ade, P and Barry, P and Braithwaite, C and Brien, TLR and Calabrese, E and Desai, S and Doyle, S and Giardiello, S and Hargrave, P and Harrison, I and Jense, HT and Lyons, M and Negrello, M and Papageorgiou, A and Rowe, S and Sudiwala, R and Tucker, C and Veenendaal, I and Viña, M and Adler, AE and Ali, A and Ashton, P and Baleato, Lizancos A and Beckman, S and Corbett, L and Crowley, KT and Cukierman, A and Ferra},
doi = {04/051},
journal = {Journal of Cosmology and Astroparticle Physics},
title = {The Simons Observatory: forecasted constraints on primordial gravitational waves with the expanded array of Small Aperture Telescopes},
url = {http://dx.doi.org/10.1088/1475-7516/2026/04/051},
volume = {2026},
year = {2026}
}
RIS format (EndNote, RefMan)
TY - JOUR
AB - We present updated forecasts for the scientific performance of the degree-scale (0.5 deg FWHM at 93 GHz), deep-field survey to be conducted by the Simons Observatory (SO). By 2027, the SO Small Aperture Telescope (SAT) complement will be doubled from three to six telescopes, including a doubling of the detector count in the 93 GHz and 145 GHz channels to 48,160 detectors. Combined with a planned extension of the survey duration to 2035, this expansion will significantly enhance SO's search for a B-mode signal in the polarisation of the cosmic microwave background, a potential signature of gravitational waves produced in the very early Universe. Assuming a 1/f noise model with knee multipole <inf>knee</inf> = 50 and a moderately complex model for Galactic foregrounds, we forecast a 1σ (or 68% confidence level) constraint on the tensor-to-scalar ratio r of σ<inf>r</inf> = 1.2 × 10<sup>-3</sup>, assuming no primordial B-modes are present. This forecast assumes that 70% of the B-mode lensing signal can ultimately be removed using high resolution observations from the SO Large Aperture Telescope (LAT) and overlapping large-scale structure surveys. For more optimistic assumptions regarding foregrounds and noise, and assuming the same level of delensing, this forecast constraint improves to σ<inf>r</inf> = 7 × 10<sup>-4</sup>. These forecasts represent a major improvement in SO's constraining power, being a factor of around 2.5 times better than what could be achieved with the originally planned campaign, which assumed the existing three SATs would conduct a five-year survey.
AU - Abril-Cabezas,I
AU - Challinor,A
AU - Clarke,P
AU - Coulton,W
AU - Embil,Villagra C
AU - Fergusson,J
AU - Legrand,L
AU - McCarthy,F
AU - Namikawa,T
AU - Sailer,N
AU - Shellard,P
AU - Sherwin,B
AU - Suman,P
AU - Zubeldia,I
AU - Bolliet,B
AU - Challinor,A
AU - Clarke,P
AU - Coulton,W
AU - Fergusson,J
AU - Hertig,E
AU - Kusiak,A
AU - Legrand,L
AU - McCarthy,F
AU - Namikawa,T
AU - Sherwin,B
AU - Adachi,S
AU - Adachi,S
AU - Ashton,P
AU - Chinone,Y
AU - Jost,B
AU - Katayama,N
AU - Kusaka,A
AU - Liu,J
AU - Matsumura,T
AU - Namikawa,T
AU - Sakurai,Y
AU - Tajima,O
AU - Takakura,S
AU - Ade,P
AU - Barry,P
AU - Braithwaite,C
AU - Brien,TLR
AU - Calabrese,E
AU - Desai,S
AU - Doyle,S
AU - Giardiello,S
AU - Hargrave,P
AU - Harrison,I
AU - Jense,HT
AU - Lyons,M
AU - Negrello,M
AU - Papageorgiou,A
AU - Rowe,S
AU - Sudiwala,R
AU - Tucker,C
AU - Veenendaal,I
AU - Viña,M
AU - Adler,AE
AU - Ali,A
AU - Ashton,P
AU - Baleato,Lizancos A
AU - Beckman,S
AU - Corbett,L
AU - Crowley,KT
AU - Cukierman,A
AU - Ferraro,S
AU - Goeckner-Wald,N
AU - Hadzhiyska,B
AU - Hill,CA
AU - Jeong,O
AU - Krolewski,A
AU - Lee,A
AU - Linder,E
AU - Prasad,B
AU - Randall,MJ
AU - Raum,C
AU - Seljak,U
AU - Song,X
AU - Stein,G
AU - Westbrook,B
AU - Yu,B
AU - Adler,AE
AU - Keskitalo,R
AU - Kisner,T
AU - Adler,AE
AU - Agrawal,P
AU - Arnold,K
AU - Bixler,B
AU - Boettger,D
AU - Chu,M
AU - Crowley,KT
AU - Flauger,R
AU - Fuller,G
AU - Green,D
AU - Idicherian,Lonappan A
AU - Johnson,A
AU - Keating,B
DO - 04/051
PY - 2026///
TI - The Simons Observatory: forecasted constraints on primordial gravitational waves with the expanded array of Small Aperture Telescopes
T2 - Journal of Cosmology and Astroparticle Physics
UR - http://dx.doi.org/10.1088/1475-7516/2026/04/051
VL - 2026
ER -