Browsing by Author "Limon, Michele"

Now showing 1 - 8 of 8
  • No Thumbnail Available
    Item
    Atacama Cosmology Telescope: High-resolution component-separated maps across one third of the sky
    (2024) Coulton, William; Madhavacheril, Mathew S.; Duivenvoorden, Adriaan J.; Hill, J. Colin; Abril-Cabezas, Irene; Ade, Peter A. R.; Aiola, Simone; Alford, Tommy; Amiri, Mandana; Amodeo, Stefania; An, Rui; Atkins, Zachary; Austermann, Jason E.; Battaglia, Nicholas; Battistelli, Elia Stefano; Beall, James A.; Bean, Rachel; Beringue, Benjamin; Bhandarkar, Tanay; Biermann, Emily; Bolliet, Boris; Bond, J. Richard; Cai, Hongbo; Calabrese, Erminia; Calafut, Victoria; Capalbo, Valentina; Carrero, Felipe; Chesmore, Grace E.; Cho, Hsiao-Mei; Choi, Steve K.; Clark, Susan E.; Rosado, Rodrigo Cordova; Cothard, Nicholas F.; Coughlin, Kevin; Crowley, Kevin T.; Devlin, Mark J.; Dicker, Simon; Doze, Peter; Duell, Cody J.; Duff, Shannon M.; Dunkley, Jo; Dunner, Rolando; Fanfani, Valentina; Fankhanel, Max; Farren, Gerrit; Ferraro, Simone; Freundt, Rodrigo; Fuzia, Brittany; Gallardo, Patricio A.; Garrido, Xavier; Givans, Jahmour; Gluscevic, Vera; Golec, Joseph E.; Guan, Yilun; Halpern, Mark; Han, Dongwon; Hasselfield, Matthew; Healy, Erin; Henderson, Shawn; Hensley, Brandon; Hervias-Caimapo, Carlos; Hilton, Gene C.; Hilton, Matt; Hincks, Adam D.; Hlozek, Renee; Ho, Shuay-Pwu Patty; Huber, Zachary B.; Hubmayr, Johannes; Huffenberger, Kevin M.; Hughes, John P.; Irwin, Kent; Isopi, Giovanni; Jense, Hidde T.; Keller, Ben; Kim, Joshua; Knowles, Kenda; Koopman, Brian J.; Kosowsky, Arthur; Kramer, Darby; Kusiak, Aleksandra; La Posta, Adrien; Lakey, Victoria; Lee, Eunseong; Li, Zack; Li, Yaqiong; Limon, Michele; Lokken, Martine; Louis, Thibaut; Lungu, Marius; MacCrann, Niall; MacInnis, Amanda; Maldonado, Diego; Maldonado, Felipe; Mallaby-Kay, Maya; Marques, Gabriela A.; van Marrewijk, Joshiwa; McCarthy, Fiona; McMahon, Jeff; Mehta, Yogesh; Menanteau, Felipe; Moodley, Kavilan; Morris, Thomas W.; Mroczkowski, Tony; Naess, Sigurd; Namikawa, Toshiya; Nati, Federico; Newburgh, Laura; Nicola, Andrina; Niemack, Michael D.; Nolta, Michael R.; Orlowski-Scherer, John; Page, Lyman A.; Pandey, Shivam; Partridge, Bruce; Prince, Heather; Puddu, Roberto; Qu, Frank J.; Radiconi, Federico; Robertson, Naomi; Rojas, Felipe; Sakuma, Tai; Salatino, Maria; Schaan, Emmanuel; Schmitt, Benjamin L.; Sehgal, Neelima; Shaikh, Shabbir; Sherwin, Blake D.; Sierra, Carlos; Sievers, Jon; Sifon, Cristobal; Simon, Sara; Sonka, Rita; Spergel, David N.; Staggs, Suzanne T.; Storer, Emilie; Switzer, Eric R.; Tampier, Niklas; Thornton, Robert; Trac, Hy; Treu, Jesse; Tucker, Carole; Ullom, Joel; Vale, Leila R.; Van Engelen, Alexander; Van Lanen, Jeff; Vargas, Cristian; Vavagiakis, Eve M.; Wagoner, Kasey; Wang, Yuhan; Wenzl, Lukas; Wollack, Edward J.; Xu, Zhilei; Zago, Fernando; Zheng, Kaiwen
    Observations of the millimeter sky contain valuable information on a number of signals, including the blackbody cosmic microwave background (CMB), Galactic emissions, and the Compton-y distortion due to the thermal Sunyaev-Zel'dovich (tSZ) effect. Extracting new insight into cosmological and astrophysical questions often requires combining multiwavelength observations to spectrally isolate one component. In this work, we present a new arc-minute-resolution Compton-y map, which traces out the line-of-sightintegrated electron pressure, as well as maps of the CMB in intensity and E-mode polarization, across a third of the sky (around 13; 000 deg2). We produce these through a joint analysis of data from the Atacama Cosmology Telescope (ACT) data release 4 and 6 at frequencies of roughly 93, 148, and 225 GHz, together with data from the Planck satellite at frequencies between 30 and 545 GHz. We present detailed verification of an internal linear combination pipeline implemented in a needlet frame that allows us to efficiently suppress Galactic contamination and account for spatial variations in the ACT instrument noise. These maps provide a significant advance, in noise levels and resolution, over the existing Planck componentseparated maps and will enable a host of science goals including studies of cluster and galaxy astrophysics, inferences of the cosmic velocity field, primordial non-Gaussianity searches, and gravitational lensing reconstruction of the CMB.
  • Thumbnail Image
    Item
    Freeform three-mirror anastigmatic large-aperture telescope and receiver optics for CMB-S4
    (2024) Gallardo, Patricio A.; Puddu, Roberto; Harrington, Kathleen; Benson, Bradford; Carlstrom, John E.; Dicker, Simon R.; Emerson, Nick; Gudmundsson, Jon E.; Limon, Michele; Mcmahon, Jeff; Nagy, Johanna M.; Natoli, Tyler; Niemack, Michael D.; Padin, Stephen; Ruhl, John; Simon, Sara M.
    CMB-S4, the next-generation ground-based cosmic microwave background (CMB) observatory, will provide detailed maps of the CMB at millimeter wavelengths to dramatically advance our understanding of the origin and evolution of the universe. CMB-S4 will deploy large- and small-aperture telescopes with hundreds of thousands of detectors to observe the CMB at arcminute and degree resolutions at millimeter wavelengths. Inflationary science benefits from a deep delensing survey at arcminute resolutions capable of observing a large field of view at millimeter wavelengths. This kind of survey acts as a complement to a degree angular resolution survey. The delensing survey requires a nearly uniform distribution of cameras per frequency band across the focal plane. We present a large-throughput (9.4 degrees field of view), large-aperture (5-m diameter) freeform three-mirror anastigmatic telescope and an array of 85 cameras for CMB observations at arcminute resolutions, which meets the needs of the delensing survey of CMB-S4. A detailed prescription of this three-mirror telescope and cameras is provided, with a series of numerical calculations that indicates expected optical performance and mechanical tolerance.
  • Thumbnail Image
    Item
    The Atacama Cosmology Telescope: A Measurement of the DR6 CMB Lensing Power Spectrum and Its Implications for Structure Growth
    (2024) Qu, Frank; Sherwin, Blake D.; Madhavacheril, Mathew S.; Han, Dongwon; Crowley, Kevin T.; Abril-Cabezas, Irene; Ade, Peter A. R.; Aiola, Simone; Alford, Tommy; Amiri, Mandana; Amodeo, Stefania; An, Rui; Atkins, Zachary; Austermann, Jason E.; Battaglia, Nicholas; Battistelli, Elia Stefano; Beall, James A.; Bean, Rachel; Beringue, Benjamin; Bhandarkar, Tanay; Biermann, Emily; Bolliet, Boris; Bond, J. Richard; Cai, Hongbo; Calabrese, Erminia; Calafut, Victoria; Capalbo, Valentina; Carrero, Felipe; Carron, Julien; Challinor, Anthony; Chesmore, Grace E.; Cho, Hsiao-Mei; Choi, Steve K.; Clark, Susan E.; Rosado, Rodrigo Cordova; Cothard, Nicholas F.; Coughlin, Kevin; Coulton, William; Dalal, Roohi; Darwish, Omar; Devlin, Mark J.; Dicker, Simon; Doze, Peter; Duell, Cody J.; Duff, Shannon M.; Duivenvoorden, Adriaan J.; Dunkley, Jo; Dunner, Rolando; Fanfani, Valentina; Fankhanel, Max; Farren, Gerrit; Ferraro, Simone; Freundt, Rodrigo; Fuzia, Brittany; Gallardo, Patricio A.; Garrido, Xavier; Gluscevic, Vera; Golec, Joseph E.; Guan, Yilun; Halpern, Mark; Harrison, Ian; Hasselfield, Matthew; Healy, Erin; Henderson, Shawn; Hensley, Brandon; Hervias-Caimapo, Carlos; Hill, J. Colin; Hilton, Gene C.; Hilton, Matt; Hincks, Adam D.; Hlozek, Renee; Ho, Shuay-Pwu Patty; Huber, Zachary B.; Hubmayr, Johannes; Huffenberger, Kevin M.; Hughes, John P.; Irwin, Kent; Isopi, Giovanni; Jense, Hidde T.; Keller, Ben; Kim, Joshua; Knowles, Kenda; Koopman, Brian J.; Kosowsky, Arthur; Kramer, Darby; Kusiak, Aleksandra; La Posta, Adrien; Lague, Alex; Lakey, Victoria; Lee, Eunseong; Li, Zack; Li, Yaqiong; Limon, Michele; Lokken, Martine; Louis, Thibaut; Lungu, Marius; MacCrann, Niall; MacInnis, Amanda; Maldonado, Diego; Maldonado, Felipe; Mallaby-Kay, Maya; Marques, Gabriela A.; McMahon, Jeff; Mehta, Yogesh; Menanteau, Felipe; Moodley, Kavilan; Morris, Thomas W.; Mroczkowski, Tony; Naess, Sigurd; Namikawa, Toshiya; Nati, Federico; Newburgh, Laura; Nicola, Andrina; Niemack, Michael D.; Nolta, Michael R.; Orlowski-Scherer, John; Page, Lyman A.; Pandey, Shivam; Partridge, Bruce; Prince, Heather; Puddu, Roberto; Radiconi, Federico; Robertson, Naomi; Rojas, Felipe; Sakuma, Tai; Salatino, Maria; Schaan, Emmanuel; Schmitt, Benjamin L.; Sehgal, Neelima; Shaikh, Shabbir; Sierra, Carlos; Sievers, Jon; Sifon, Cristobal; Simon, Sara; Sonka, Rita; Spergel, David N.; Staggs, Suzanne T.; Storer, Emilie; Switzer, Eric R.; Tampier, Niklas; Thornton, Robert; Trac, Hy; Treu, Jesse; Tucker, Carole; Ullom, Joel; Vale, Leila R.; Van Engelen, Alexander; Van Lanen, Jeff; van Marrewijk, Joshiwa; Vargas, Cristian; Vavagiakis, Eve M.; Wagoner, Kasey; Wang, Yuhan; Wenzl, Lukas; Wollack, Edward J.; Xu, Zhilei; Zago, Fernando; Zheng, Kaiwen
    We present new measurements of cosmic microwave background (CMB) lensing over 9400 deg2 of the sky. These lensing measurements are derived from the Atacama Cosmology Telescope (ACT) Data Release 6 (DR6) CMB data set, which consists of five seasons of ACT CMB temperature and polarization observations. We determine the amplitude of the CMB lensing power spectrum at 2.3% precision (43 sigma significance) using a novel pipeline that minimizes sensitivity to foregrounds and to noise properties. To ensure that our results are robust, we analyze an extensive set of null tests, consistency tests, and systematic error estimates and employ a blinded analysis framework. Our CMB lensing power spectrum measurement provides constraints on the amplitude of cosmic structure that do not depend on Planck or galaxy survey data, thus giving independent information about large-scale structure growth and potential tensions in structure measurements. The baseline spectrum is well fit by a lensing amplitude of A lens = 1.013 +/- 0.023 relative to the Planck 2018 CMB power spectra best-fit Lambda CDM model and A lens = 1.005 +/- 0.023 relative to the ACT DR4 + WMAP best-fit model. From our lensing power spectrum measurement, we derive constraints on the parameter combination S8CMBL equivalent to sigma 8 omega m/0.30.25 of S8CMBL=0.818 +/- 0.022 from ACT DR6 CMB lensing alone and S8CMBL=0.813 +/- 0.018 when combining ACT DR6 and Planck NPIPE CMB lensing power spectra. These results are in excellent agreement with Lambda CDM model constraints from Planck or ACT DR4 + WMAP CMB power spectrum measurements. Our lensing measurements from redshifts z similar to 0.5-5 are thus fully consistent with Lambda CDM structure growth predictions based on CMB anisotropies probing primarily z similar to 1100. We find no evidence for a suppression of the amplitude of cosmic structure at low redshifts.
  • No Thumbnail Available
    Item
    THE ATACAMA COSMOLOGY TELESCOPE: CALIBRATION WITH THE WILKINSON MICROWAVE ANISOTROPY PROBE USING CROSS-CORRELATIONS
    (2011) Hajian, Amir; Acquaviva, Viviana; Ade, Peter A. R.; Aguirre, Paula; Amiri, Mandana; Appel, John William; Felipe Barrientos, L.; Battistelli, Elia S.; Bond, John R.; Brown, Ben; Burger, Bryce; Chervenak, Jay; Das, Sudeep; Devlin, Mark J.; Dicker, Simon R.; Doriese, W. Bertrand; Dunkley, Joanna; Duenner, Rolando; Essinger-Hileman, Thomas; Fisher, Ryan P.; Fowler, Joseph W.; Halpern, Mark; Hasselfield, Matthew; Hernandez-Monteagudo, Carlos; Hilton, Gene C.; Hilton, Matt; Hincks, Adam D.; Hlozek, Renee; Huffenberger, Kevin M.; Hughes, David H.; Hughes, John P.; Infante, Leopoldo; Irwin, Kent D.; Baptiste Juin, Jean; Kaul, Madhuri; Klein, Jeff; Kosowsky, Arthur; Lau, Judy M.; Limon, Michele; Lin, Yen-Ting; Lupton, Robert H.; Marriage, Tobias A.; Marsden, Danica; Mauskopf, Phil; Menanteau, Felipe; Moodley, Kavilan; Moseley, Harvey; Netterfield, Calvin B.; Niemack, Michael D.; Nolta, Michael R.; Page, Lyman A.; Parker, Lucas; Partridge, Bruce; Reid, Beth; Sehgal, Neelima; Sherwin, Blake D.; Sievers, Jon; Spergel, David N.; Staggs, Suzanne T.; Swetz, Daniel S.; Switzer, Eric R.; Thornton, Robert; Trac, Hy; Tucker, Carole; Warne, Ryan; Wollack, Ed; Zhao, Yue
    We present a new calibration method based on cross-correlations with the Wilkinson Microwave Anisotropy Probe (WMAP) and apply it to data from the Atacama Cosmology Telescope (ACT). ACT's observing strategy and map-making procedure allows an unbiased reconstruction of the modes in the maps over a wide range of multipoles. By directly matching the ACT maps to WMAP observations in the multipole range of 400 < l < 1000, we determine the absolute calibration with an uncertainty of 2% in temperature. The precise measurement of the calibration error directly impacts the uncertainties in the cosmological parameters estimated from the ACT power spectra. We also present a combined map based on ACT and WMAP data that has a high signal-to-noise ratio over a wide range of multipoles.
  • Thumbnail Image
    Item
    The Atacama Cosmology Telescope: DR6 Gravitational Lensing Map and Cosmological Parameters
    (2024) Madhavacheril, Mathew S.; Qu, Frank J.; Sherwin, Blake D.; Maccrann, Niall; Li, Yaqiong; Abril-Cabezas, Irene; Ade, Peter A. R.; Aiola, Simone; Alford, Tommy; Amiri, Mandana; Amodeo, Stefania; An, Rui; Atkins, Zachary; Austermann, Jason E.; Battaglia, Nicholas; Battistelli, Elia Stefano; Beall, James A.; Bean, Rachel; Beringue, Benjamin; Bhandarkar, Tanay; Biermann, Emily; Bolliet, Boris; Bond, J. Richard; Cai, Hongbo; Calabrese, Erminia; Calafut, Victoria; Capalbo, Valentina; Carrero, Felipe; Challinor, Anthony; Chesmore, Grace E.; Cho, Hsiao-mei; Choi, Steve K.; Clark, Susan E.; Rosado, Rodrigo Cordova; Cothard, Nicholas F.; Coughlin, Kevin; Coulton, William; Crowley, Kevin T.; Dalal, Roohi; Darwish, Omar; Devlin, Mark J.; Dicker, Simon; Doze, Peter; Duell, Cody J.; Duff, Shannon M.; Duivenvoorden, Adriaan J.; Dunkley, Jo; Duenner, Rolando; Fanfani, Valentina; Fankhanel, Max; Farren, Gerrit; Ferraro, Simone; Freundt, Rodrigo; Fuzia, Brittany; Gallardo, Patricio A.; Garrido, Xavier; Givans, Jahmour; Gluscevic, Vera; Golec, Joseph E.; Guan, Yilun; Hall, Kirsten R.; Halpern, Mark; Han, Dongwon; Harrison, Ian; Hasselfield, Matthew; Healy, Erin; Henderson, Shawn; Hensley, Brandon; Hervias-Caimapo, Carlos; Hill, J. Colin; Hilton, Gene C.; Hilton, Matt; Hincks, Adam D.; Hlozek, Renee; Ho, Shuay-Pwu Patty; Huber, Zachary B.; Hubmayr, Johannes; Huffenberger, Kevin M.; Hughes, John P.; Irwin, Kent; Isopi, Giovanni; Jense, Hidde T.; Keller, Ben; Kim, Joshua; Knowles, Kenda; Koopman, Brian J.; Kosowsky, Arthur; Kramer, Darby; Kusiak, Aleksandra; La Posta, Adrien; Lague, Alex; Lakey, Victoria; Lee, Eunseong; Li, Zack; Limon, Michele; Lokken, Martine; Louis, Thibaut; Lungu, Marius; Macinnis, Amanda; Maldonado, Diego; Maldonado, Felipe; Mallaby-Kay, Maya; Marques, Gabriela A.; Mcmahon, Jeff; Mehta, Yogesh; Menanteau, Felipe; Moodley, Kavilan; Morris, Thomas W.; Mroczkowski, Tony; Naess, Sigurd; Namikawa, Toshiya; Nati, Federico; Newburgh, Laura; Nicola, Andrina; Niemack, Michael D.; Nolta, Michael R.; Orlowski-Scherer, John; Page, Lyman A.; Pandey, Shivam; Partridge, Bruce; Prince, Heather; Puddu, Roberto; Radiconi, Federico; Robertson, Naomi; Rojas, Felipe; Sakuma, Tai; Salatino, Maria; Schaan, Emmanuel; Schmitt, Benjamin L.; Sehgal, Neelima; Shaikh, Shabbir; Sierra, Carlos; Sievers, Jon; Sifon, Cristobal; Simon, Sara; Sonka, Rita; Spergel, David N.; Staggs, Suzanne T.; Storer, Emilie; Switzer, Eric R.; Tampier, Niklas; Thornton, Robert; Trac, Hy; Treu, Jesse; Tucker, Carole; Ullom, Joel; Vale, Leila R.; Van Engelen, Alexander; Van Lanen, Jeff; van Marrewijk, Joshiwa; Vargas, Cristian; Vavagiakis, Eve M.; Wagoner, Kasey; Wang, Yuhan; Wenzl, Lukas; Wollack, Edward J.; Xu, Zhilei; Zago, Fernando; Zheng, Kaiwen
    We present cosmological constraints from a gravitational lensing mass map covering 9400 sq. deg(2). reconstructed from CMB measurements made by the Atacama Cosmology Telescope (ACT) from 2017 to 2021. In combination with BAO measurements (from SDSS and 6dF), we obtain the amplitude of matter fluctuations sigma(8)=0.819 +/- 0.015 at 1.8% precision, S-8 equivalent to sigma(8)(Omega(m)/0.3)(0.5)=0.840 +/- 0.028 and the Hubble constant H-0=(68.3 +/- 1.1)kms(-1)Mpc(-1) at 1.6% precision. A joint constraint with CMB lensing measured by the Planck satellite yields even more precise values: sigma(8)=0.812 +/- 0.013, S-8 equivalent to sigma(8)(Omega m/0.3)(0.5)=0.831 +/- 0.023 and H-0=(68.1 +/- 1.0)kms(-1)Mpc(-1). These measurements agree well with Lambda CDM-model extrapolations from the CMB anisotropies measured by Planck. To compare these constraints to those from the KiDS, DES, and HSC galaxy surveys, we revisit those data sets with a uniform set of assumptions, and find S-8 from all three surveys are lower than that from ACT+Planck lensing by varying levels ranging from 1.7-2.1 sigma. These results motivate further measurements and comparison, not just between the CMB anisotropies and galaxy lensing, but also between CMB lensing probing z similar to 0.5-5 on mostly-linear scales and galaxy lensing at z similar to 0.5 on smaller scales. We combine our CMB lensing measurements with CMB anisotropies to constrain extensions of Lambda CDM, limiting the sum of the neutrino masses to & sum;m(nu)<0.12 eV (95% c.l.), for example. Our results provide independent confirmation that the universe is spatially flat, conforms with general relativity, and is described remarkably well by the Lambda CDM model, while paving a promising path for neutrino physics with gravitational lensing from upcoming ground-based CMB surveys
  • No Thumbnail Available
    Item
    The Atacama Cosmology Telescope: Sunyaev-Zel'dovich-Selected Galaxy Clusters at 148 GHz in the 2008 Survey
    (2011) Marriage, Tobias A.; Acquaviva, Viviana; Ade, Peter A. R.; Aguirre, Paula; Amiri, Mandana; Appel, John William; Barrientos, L. Felipe; Battistelli, Elia S.; Bond, J. Richard; Brown, Ben; Burger, Bryce; Chervenak, Jay; Das, Sudeep; Devlin, Mark J.; Dicker, Simon R.; Bertrand Doriese, W.; Dunkley, Joanna; Dünner, Rolando; Essinger-Hileman, Thomas; Fisher, Ryan P.; Fowler, Joseph W.; Hajian, Amir; Halpern, Mark; Hasselfield, Matthew; Hernández-Monteagudo, Carlos; Hilton, Gene C.; Hilton, Matt; Hincks, Adam D.; Hlozek, Renée; Huffenberger, Kevin M.; Handel Hughes, David; Hughes, John P.; Infante, Leopoldo; Irwin, Kent D.; Baptiste Juin, Jean; Kaul, Madhuri; Klein, Jeff; Kosowsky, Arthur; Lau, Judy M.; Limon, Michele; Lin, Yen-Ting; Lupton, Robert H.; Marsden, Danica; Martocci, Krista; Mauskopf, Phil; Menanteau, Felipe; Moodley, Kavilan; Moseley, Harvey; Netterfield, Calvin B.; Niemack, Michael D.; Nolta, Michael R.; Page, Lyman A.; Parker, Lucas; Partridge, Bruce; Quintana, Hernan; Reese, Erik D.; Reid, Beth; Sehgal, Neelima; Sherwin, Blake D.; Sievers, Jon; Spergel, David N.; Staggs, Suzanne T.; Swetz, Daniel S.; Switzer, Eric R.; Thornton, Robert; Trac, Hy; Tucker, Carole; Warne, Ryan; Wilson, Grant; Wollack, Ed; Zhao, Yue
    We report on 23 clusters detected blindly as Sunyaev-Zel'dovich (SZ) decrements in a 148 GHz, 455 deg(2) map of the southern sky made with data from the Atacama Cosmology Telescope 2008 observing season. All SZ detections announced in this work have confirmed optical counterparts. Ten of the clusters are new discoveries. One newly discovered cluster, ACT-CL J0102-4915, with a redshift of 0.75 ( photometric), has an SZ decrement comparable to the most massive systems at lower redshifts. Simulations of the cluster recovery method reproduce the sample purity measured by optical follow-up. In particular, for clusters detected with a signal-to-noise ratio greater than six, simulations are consistent with optical follow-up that demonstrated this subsample is 100% pure. The simulations further imply that the total sample is 80% complete for clusters with mass in excess of 6 x 10(14) solar masses referenced to the cluster volume characterized by 500 times the critical density. The Compton y-X-ray luminosity mass comparison for the 11 best-detected clusters visually agrees with both self-similar and non-adiabatic, simulation-derived scaling laws.
  • No Thumbnail Available
    Item
    The Simons Observatory Large Aperture Telescope Receiver
    (2021) Zhu, Ningfeng; Bhandarkar, Tanay; Coppi, Gabriele; Kofman, Anna M.; Orlowski-Scherer, John L.; Xu, Zhilei; Adachi, Shunsuke; Ade, Peter; Aiola, Simone; Austermann, Jason; Bazarko, Andrew O.; Beall, James A.; Bhimani, Sanah; Bond, J. Richard; Chesmore, Grace E.; Choi, Steve K.; Connors, Jake; Cothard, Nicholas F.; Devlin, Mark; Dicker, Simon; Dober, Bradley; Duell, Cody J.; Duff, Shannon M.; Dunner, Rolando; Fabbian, Giulio; Galitzki, Nicholas; Gallardo, Patricio A.; Golec, Joseph E.; Haridas, Saianeesh K.; Harrington, Kathleen; Healy, Erin; Ho, Shuay-Pwu Patty; Huber, Zachary B.; Hubmayr, Johannes; Iuliano, Jeffrey; Johnson, Bradley R.; Keating, Brian; Kiuchi, Kenji; Koopman, Brian J.; Lashner, Jack; Lee, Adrian T.; Li, Yaqiong; Limon, Michele; Link, Michael; Lucas, Tammy J.; McCarrick, Heather; Moore, Jenna; Nati, Federico; Newburgh, Laura B.; Niemack, Michael D.; Pierpaoli, Elena; Randall, Michael J.; Sarmiento, Karen Perez; Saunders, Lauren J.; Seibert, Joseph; Sierra, Carlos; Sonka, Rita; Spisak, Jacob; Sutariya, Shreya; Tajima, Osamu; Teply, Grant P.; Thornton, Robert J.; Tsan, Tran; Tucker, Carole; Ullom, Joel; Vavagiakis, Eve M.; Vissers, Michael R.; Walker, Samantha; Westbrook, Benjamin; Wollack, Edward J.; Zannoni, Mario
    The Simons Observatory is a ground-based cosmic microwave background experiment that consists of three 0.4 m small-aperture telescopes and one 6 m Large Aperture Telescope, located at an elevation of 5300 m on Cerro Toco in Chile. The Simons Observatory Large Aperture Telescope Receiver (LATR) is the cryogenic camera that will be coupled to the Large Aperture Telescope. The resulting instrument will produce arcminute-resolution millimeter-wave maps of half the sky with unprecedented precision. The LATR is the largest cryogenic millimeter-wave camera built to date, with a diameter of 2.4 m and a length of 2.6 m. The coldest stage of the camera is cooled to 100 mK, the operating temperature of the bolometric detectors with bands centered around 27, 39, 93, 145, 225, and 280 GHz. Ultimately, the LATR will accommodate 13 40 cm diameter optics tubes, each with three detector wafers and a total of 62,000 detectors. The LATR design must simultaneously maintain the optical alignment of the system, control stray light, provide cryogenic isolation, limit thermal gradients, and minimize the time to cool the system from room temperature to 100 mK. The interplay between these competing factors poses unique challenges. We discuss the trade studies involved with the design, the final optimization, the construction, and ultimate performance of the system.
  • No Thumbnail Available
    Item
    The Simons Observatory: modeling optical systematics in the Large Aperture Telescope
    (2021) Gudmundsson, Jon E.; Gallardo, Patricio A.; Puddu, Roberto; Dicker, Simon R.; Adler, Alexandre E.; Ali, Aamir M.; Bazarko, Andrew; Chesmore, Grace E.; Coppi, Gabriele; Cothard, Nicholas F.; Dachlythra, Nadia; Devlin, Mark; Dunner, Rolando; Fabbian, Giulio; Galitzki, Nicholas; Golec, Joseph E.; Ho, Shuay-Pwu Patty; Hargrave, Peter C.; Kofman, Anna M.; Lee, Adrian T.; Limon, Michele; Matsuda, Frederick T.; Mauskopf, Philip D.; Moodley, Kavilan; Nati, Federico; Niemack, Michael D.; Orlowski-Scherer, John; Page, Lyman A.; Partridge, Bruce; Puglisi, Giuseppe; Reichardt, Christian L.; Sierra, Carlos E.; Simon, Sara M.; Teply, Grant P.; Tucker, Carole; Wollack, Edward J.; Xu, Zhilei; Zhu, Ningfeng
    We present geometrical and physical optics simulation results for the Simons Observatory Large Aperture Telescope. This work was developed as part of the general design process for the telescope, allowing us to evaluate the impact of various design choices on performance metrics and potential systematic effects. The primary goal of the simulations was to evaluate the final design of the reflectors and the cold optics that are now being built. We describe nonsequential ray tracing used to inform the design of the cold optics, including absorbers internal to each optics tube. We discuss ray tracing simulations of the telescope structure that allow us to determine geometries that minimize detector loading and mitigate spurious near-field effects that have not been resolved by the internal baffling. We also describe physical optics simulations, performed over a range of frequencies and field locations, that produce estimates of monochromatic far-field beam patterns, which in turn are used to gauge general optical performance. Finally, we describe simulations that shed light on beam sidelobes from panel gap diffraction. (C) 2021 Optical Society of America