Search

Your search keyword '"Cothard N. F."' showing total 30 results
Start Over Author "Cothard N. F."
30 results on '"Cothard N. F."'

4. CCAT-prime Collaboration: Science Goals and Forecasts with Prime-Cam on the Fred Young Submillimeter Telescope

Author

collaboration, CCAT-Prime, Aravena, M., Austermann, J. E., Basu, K., Battaglia, N., Beringue, B., Bertoldi, F., Bigiel, F., Bond, J. R., Breysse, P. C., Broughton, C., Bustos, R., Chapman, S. C., Charmetant, M., Choi, S. K., Chung, D. T., Clark, S. E., Cothard, N. F., Crites, A. T., Dev, A., Douglas, K., Duell, C. J., Dunner, R., Ebina, H., Erler, J., Fich, M., Fissel, L. M., Foreman, S., Gallardo, P. A., Gao, J., García, Pablo, Giovanelli, R., Golec, J. E., Groppi, C. E., Haynes, M. P., Henke, D., Hensley, B., Herter, T., Higgins, R., Hlozek, R., Huber, A., Huber, Z., Hubmayr, J., Jackson, R., Johnstone, D., Karoumpis, C., Keating, L. C., Komatsu, E., Li, Y., Magnelli, B., Matthews, B. C., Mauskopf, P., McMahon, J. J., Meerburg, P. D., Meyers, J., Muralidhara, V., Murray, N. W., Niemack, M. D., Nikola, T., Okada, Y., Puddu, R., Riechers, D. A., Rosolowsky, E., Rossi, K., Rotermund, K., Roy, A., Sadavoy, S. I., Schaaf, R., Schilke, P., Scott, D., Simon, R., Sinclair, Adrian K., Sivakoff, G. R., Stacey, G. J., Stutz, Amelia M., Stutzki, J., Tahani, M., Thanjavur, K., Timmermann, R. A., Ullom, J. N., van Engelen, A., Vavagiakis, E. M., Vissers, M. R., Wheeler, J. D., White, S. D. M., Zhu, Y., and Zou, B.

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

We present a detailed overview of the science goals and predictions for the Prime-Cam direct detection camera/spectrometer being constructed by the CCAT-prime collaboration for dedicated use on the Fred Young Submillimeter Telescope (FYST). The FYST is a wide-field, 6-m aperture submillimeter telescope being built (first light in mid-2024) by an international consortium of institutions led by Cornell University and sited at more than 5600 meters on Cerro Chajnantor in northern Chile. Prime-Cam is one of two instruments planned for FYST and will provide unprecedented spectroscopic and broadband measurement capabilities to address important astrophysical questions ranging from Big Bang cosmology through reionization and the formation of the first galaxies to star formation within our own Milky Way galaxy. Prime-Cam on the FYST will have a mapping speed that is over ten times greater than existing and near-term facilities for high-redshift science and broadband polarimetric imaging at frequencies above 300 GHz. We describe details of the science program enabled by this system and our preliminary survey strategies., Comment: 61 pages, 16 figures. Resubmitted to ApJSS July 11, 2022

Published
2021
Full Text
View/download PDF

6. Developing AlMn films for Argonne TES fabrication

Author

Vavagiakis, E. M., Cothard, N. F., Stevens, J. R., Chang, C. L., Niemack, M. D., Wang, G., Yefremenko, V. G., and Zhang, J.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Physics - Instrumentation and Detectors
Abstract

The reference design for the next-generation cosmic microwave background (CMB) experiment, CMB-S4, relies on large arrays of transition edge sensor (TES) bolometers coupled to Superconducting Quantum Interference Device (SQUID)-based readout systems. Mapping the CMB to near cosmic variance limits will enable the search for signatures of inflation and constrain dark energy and neutrino physics. AlMn TESes provide simple film manufacturing and highly uniform arrays over large areas to meet the requirements of the CMB-S4 experiment. TES parameters such as critical temperature and normal resistance must be tuned to experiment specifications and can be varied based on geometry and steps in the fabrication process such as deposition layering, geometry, and baking time and temperature. Using four-terminal sensing, we measured $T_C$ and $R_N$ of AlMn 2000 ppm films and devices of varying thicknesses fabricated at Argonne National Laboratory to motivate device geometries and fabrication processes to tune $T_C$ to 150-200 mK and $R_N$ to $\sim$10 mOhms. Measurements of IV curves and time constants for the resulting devices of varying leg length were made using time-division SQUID multiplexing, and determined $T_C$, $G$, $k$, $f_{3db}$, and $R_N$. We present the results of these tests along with the geometries and fabrication steps used to tune the device parameters to the desired limits., Comment: 7 pages, 5 figures, 18th International Workshop on Low Temperature Detectors, submitted to the Journal of Low Temperature Physics

Published
2019
Full Text
View/download PDF

7. Sidelobe analysis for the Atacama Cosmology Telescope: a novel method for importing models in GRASP

Author

Puddu, R., Cothard, N. F., Gallardo, P. A., Dünner, R., and Fluxá, P.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

Telescopes for observing the Cosmic Microwave Background (CMB) usually have shields and baffle structures in order to reduce the pickup from the ground. These structures may introduce unwanted sidelobes. We present a method to measure and model baffling structures of large aperture telescope optics to predict the sidelobe pattern.

Published
2019

8. Magnetic Sensitivity of AlMn TESes and Shielding Considerations for Next-Generation CMB Surveys

Author

Vavagiakis, E. M., Henderson, S. W., Zheng, K., Cho, H. -M., Cothard, N. F., Dober, B., Duff, S. M., Gallardo, P. A., Hilton, G., Hubmayr, J., Irwin, K. D., Koopman, B. J., Li, D., Nati, F., Niemack, M. D., Reintsema, C. D., Simon, S., Stevens, J. R., Suzuki, A., and Westbrook, B.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

In the next decade, new ground-based Cosmic Microwave Background (CMB) experiments such as Simons Observatory (SO), CCAT-prime, and CMB-S4 will increase the number of detectors observing the CMB by an order of magnitude or more, dramatically improving our understanding of cosmology and astrophysics. These projects will deploy receivers with as many as hundreds of thousands of transition edge sensor (TES) bolometers coupled to Superconducting Quantum Interference Device (SQUID)-based readout systems. It is well known that superconducting devices such as TESes and SQUIDs are sensitive to magnetic fields. However, the effects of magnetic fields on TESes are not easily predicted due to the complex behavior of the superconducting transition, which motivates direct measurements of the magnetic sensitivity of these devices. We present comparative four-lead measurements of the critical temperature versus applied magnetic field of AlMn TESes varying in geometry, doping, and leg length, including Advanced ACT (AdvACT) and POLARBEAR-2/Simons Array bolometers. Molybdenum-copper bilayer ACTPol TESes are also tested and are found to be more sensitive to magnetic fields than the AlMn devices. We present an observation of weak-link-like behavior in AlMn TESes at low critical currents. We also compare measurements of magnetic sensitivity for time division multiplexing SQUIDs and frequency division multiplexing microwave rf-SQUIDs. We discuss the implications of our measurements on the magnetic shielding required for future experiments that aim to map the CMB to near-fundamental limits., Comment: 8 pages, 4 figures, conference proceedings submitted to the Journal of Low Temperature Physics

Published
2017
Full Text
View/download PDF

9. Atacama Cosmology Telescope: High-resolution component-separated maps across one third of the sky

Author

Coulton, W, Madhavacheril, M, Duivenvoorden, A, Hill, J, Abril-Cabezas, I, Ade, P, Aiola, S, Alford, T, Amiri, M, Amodeo, S, An, R, Atkins, Z, Austermann, J, Battaglia, N, Battistelli, E, Beall, J, Bean, R, Beringue, B, Bhandarkar, T, Biermann, E, Bolliet, B, Bond, J, Cai, H, Calabrese, E, Calafut, V, Capalbo, V, Carrero, F, Chesmore, G, Cho, H, Choi, S, Clark, S, Rosado, R, Cothard, N, Coughlin, K, Crowley, K, Devlin, M, Dicker, S, Doze, P, Duell, C, Duff, S, Dunkley, J, Dünner, R, Fanfani, V, Fankhanel, M, Farren, G, Ferraro, S, Freundt, R, Fuzia, B, Gallardo, P, Garrido, X, Givans, J, Gluscevic, V, Golec, J, Guan, Y, Halpern, M, Han, D, Hasselfield, M, Healy, E, Henderson, S, Hensley, B, Hervías-Caimapo, C, Hilton, G, Hilton, M, Hincks, A, Hložek, R, Ho, S, Huber, Z, Hubmayr, J, Huffenberger, K, Hughes, J, Irwin, K, Isopi, G, Jense, H, Keller, B, Kim, J, Knowles, K, Koopman, B, Kosowsky, A, Kramer, D, Kusiak, A, La Posta, A, Lakey, V, Lee, E, Li, Z, Li, Y, Limon, M, Lokken, M, Louis, T, Lungu, M, Maccrann, N, Macinnis, A, Maldonado, D, Maldonado, F, Mallaby-Kay, M, Marques, G, Van Marrewijk, J, Mccarthy, F, Mcmahon, J, Mehta, Y, Menanteau, F, Coulton W., Madhavacheril M. S., Duivenvoorden A. J., Hill J. C., Abril-Cabezas I., Ade P. A. R., Aiola S., Alford T., Amiri M., Amodeo S., An R., Atkins Z., Austermann J. E., Battaglia N., Battistelli E. S., Beall J. A., Bean R., Beringue B., Bhandarkar T., Biermann E., Bolliet B., Bond J. R., Cai H., Calabrese E., Calafut V., Capalbo V., Carrero F., Chesmore G. E., Cho H. M., Choi S. K., Clark S. E., Rosado R. C., Cothard N. F., Coughlin K., Crowley K. T., Devlin M. J., Dicker S., Doze P., Duell C. J., Duff S. M., Dunkley J., Dünner R., Fanfani V., Fankhanel M., Farren G., Ferraro S., Freundt R., Fuzia B., Gallardo P. A., Garrido X., Givans J., Gluscevic V., Golec J. E., Guan Y., Halpern M., Han D., Hasselfield M., Healy E., Henderson S., Hensley B., Hervías-Caimapo C., Hilton G. C., Hilton M., Hincks A. D., HloŽek R., Ho S. P. P., Huber Z. B., Hubmayr J., Huffenberger K. M., Hughes J. P., Irwin K., Isopi G., Jense H. T., Keller B., Kim J., Knowles K., Koopman B. J., Kosowsky A., Kramer D., Kusiak A., La Posta A., Lakey V., Lee E., Li Z., Li Y., Limon M., Lokken M., Louis T., Lungu M., Maccrann N., Macinnis A., Maldonado D., Maldonado F., Mallaby-Kay M., Marques G. A., Van Marrewijk J., McCarthy F., McMahon J., Mehta Y., Menanteau F., Coulton, W, Madhavacheril, M, Duivenvoorden, A, Hill, J, Abril-Cabezas, I, Ade, P, Aiola, S, Alford, T, Amiri, M, Amodeo, S, An, R, Atkins, Z, Austermann, J, Battaglia, N, Battistelli, E, Beall, J, Bean, R, Beringue, B, Bhandarkar, T, Biermann, E, Bolliet, B, Bond, J, Cai, H, Calabrese, E, Calafut, V, Capalbo, V, Carrero, F, Chesmore, G, Cho, H, Choi, S, Clark, S, Rosado, R, Cothard, N, Coughlin, K, Crowley, K, Devlin, M, Dicker, S, Doze, P, Duell, C, Duff, S, Dunkley, J, Dünner, R, Fanfani, V, Fankhanel, M, Farren, G, Ferraro, S, Freundt, R, Fuzia, B, Gallardo, P, Garrido, X, Givans, J, Gluscevic, V, Golec, J, Guan, Y, Halpern, M, Han, D, Hasselfield, M, Healy, E, Henderson, S, Hensley, B, Hervías-Caimapo, C, Hilton, G, Hilton, M, Hincks, A, Hložek, R, Ho, S, Huber, Z, Hubmayr, J, Huffenberger, K, Hughes, J, Irwin, K, Isopi, G, Jense, H, Keller, B, Kim, J, Knowles, K, Koopman, B, Kosowsky, A, Kramer, D, Kusiak, A, La Posta, A, Lakey, V, Lee, E, Li, Z, Li, Y, Limon, M, Lokken, M, Louis, T, Lungu, M, Maccrann, N, Macinnis, A, Maldonado, D, Maldonado, F, Mallaby-Kay, M, Marques, G, Van Marrewijk, J, Mccarthy, F, Mcmahon, J, Mehta, Y, Menanteau, F, Coulton W., Madhavacheril M. S., Duivenvoorden A. J., Hill J. C., Abril-Cabezas I., Ade P. A. R., Aiola S., Alford T., Amiri M., Amodeo S., An R., Atkins Z., Austermann J. E., Battaglia N., Battistelli E. S., Beall J. A., Bean R., Beringue B., Bhandarkar T., Biermann E., Bolliet B., Bond J. R., Cai H., Calabrese E., Calafut V., Capalbo V., Carrero F., Chesmore G. E., Cho H. M., Choi S. K., Clark S. E., Rosado R. C., Cothard N. F., Coughlin K., Crowley K. T., Devlin M. J., Dicker S., Doze P., Duell C. J., Duff S. M., Dunkley J., Dünner R., Fanfani V., Fankhanel M., Farren G., Ferraro S., Freundt R., Fuzia B., Gallardo P. A., Garrido X., Givans J., Gluscevic V., Golec J. E., Guan Y., Halpern M., Han D., Hasselfield M., Healy E., Henderson S., Hensley B., Hervías-Caimapo C., Hilton G. C., Hilton M., Hincks A. D., HloŽek R., Ho S. P. P., Huber Z. B., Hubmayr J., Huffenberger K. M., Hughes J. P., Irwin K., Isopi G., Jense H. T., Keller B., Kim J., Knowles K., Koopman B. J., Kosowsky A., Kramer D., Kusiak A., La Posta A., Lakey V., Lee E., Li Z., Li Y., Limon M., Lokken M., Louis T., Lungu M., Maccrann N., Macinnis A., Maldonado D., Maldonado F., Mallaby-Kay M., Marques G. A., Van Marrewijk J., McCarthy F., McMahon J., Mehta Y., and Menanteau F.

Abstract

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-sight-integrated 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 component-separated 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.

Published
2024

11. Sensitivity of the Prime-Cam Instrument on the CCAT-Prime Telescope

Author

Choi, S. K., Austermann, J., Basu, K., Battaglia, N., Bertoldi, F., Chung, D. T., Cothard, N. F., Duff, S., Duell, C. J., Gallardo, P. A., Gao, J., Herter, T., Hubmayr, J., Niemack, M. D., Nikola, T., Riechers, D., Rossi, K., Stacey, G. J., Stevens, J. R., Vavagiakis, E. M., Vissers, M., and Walker, S.

Published
2020
Full Text
View/download PDF

14. The Advanced ACTPol 27/39 GHz Array

Author

Simon, S. M., Beall, J. A., Cothard, N. F., Duff, S. M., Gallardo, P. A., Ho, S. P., Hubmayr, J., Koopman, B. J., McMahon, J. J., Nati, F., Niemack, M. D., Staggs, S. T., Vavagiakis, E. M., and Wollack, E. J.

Published
2018
Full Text
View/download PDF

17. The Atacama Cosmology Telescope: Detection of the pairwise kinematic Sunyaev-Zel’dovich effect with SDSS DR15 galaxies

Author

Calafut, V., primary, Gallardo, P. A., additional, Vavagiakis, E. M., additional, Amodeo, S., additional, Aiola, S., additional, Austermann, J. E., additional, Battaglia, N., additional, Battistelli, E. S., additional, Beall, J. A., additional, Bean, R., additional, Bond, J. R., additional, Calabrese, E., additional, Choi, S. K., additional, Cothard, N. F., additional, Devlin, M. J., additional, Duell, C. J., additional, Duff, S. M., additional, Duivenvoorden, A. J., additional, Dunkley, J., additional, Dunner, R., additional, Ferraro, S., additional, Guan, Y., additional, Hill, J. C., additional, Hilton, G. C., additional, Hilton, M., additional, Hložek, R., additional, Huber, Z. B., additional, Hubmayr, J., additional, Huffenberger, K. M., additional, Hughes, J. P., additional, Koopman, B. J., additional, Kosowsky, A., additional, Li, Y., additional, Lokken, M., additional, Madhavacheril, M., additional, McMahon, J., additional, Moodley, K., additional, Naess, S., additional, Nati, F., additional, Newburgh, L. B., additional, Niemack, M. D., additional, Page, L. A., additional, Partridge, B., additional, Schaan, E., additional, Schillaci, A., additional, Sifón, C., additional, Spergel, D. N., additional, Staggs, S. T., additional, Ullom, J. N., additional, Vale, L. R., additional, Van Engelen, A., additional, Van Lanen, J., additional, Wollack, E. J., additional, and Xu, Z., additional

Published
2021
Full Text
View/download PDF

18. The Atacama Cosmology Telescope: Probing the baryon content of SDSS DR15 galaxies with the thermal and kinematic Sunyaev-Zel’dovich effects

Author

Vavagiakis, E. M., primary, Gallardo, P. A., additional, Calafut, V., additional, Amodeo, S., additional, Aiola, S., additional, Austermann, J. E., additional, Battaglia, N., additional, Battistelli, E. S., additional, Beall, J. A., additional, Bean, R., additional, Bond, J. R., additional, Calabrese, E., additional, Choi, S. K., additional, Cothard, N. F., additional, Devlin, M. J., additional, Duell, C. J., additional, Duff, S. M., additional, Duivenvoorden, A. J., additional, Dunkley, J., additional, Dunner, R., additional, Ferraro, S., additional, Guan, Y., additional, Hill, J. C., additional, Hilton, G. C., additional, Hilton, M., additional, Hložek, R., additional, Huber, Z. B., additional, Hubmayr, J., additional, Huffenberger, K. M., additional, Hughes, J. P., additional, Koopman, B. J., additional, Kosowsky, A., additional, Li, Y., additional, Lokken, M., additional, Madhavacheril, M., additional, McMahon, J., additional, Moodley, K., additional, Naess, S., additional, Nati, F., additional, Newburgh, L. B., additional, Niemack, M. D., additional, Page, L. A., additional, Partridge, B., additional, Schaan, E., additional, Schillaci, A., additional, Sifón, C., additional, Spergel, D. N., additional, Staggs, S. T., additional, Ullom, J. N., additional, Vale, L. R., additional, Van Engelen, A., additional, Van Lanen, J., additional, Wollack, E. J., additional, and Xu, Z., additional

Published
2021
Full Text
View/download PDF

19. Erratum: The Simons Observatory Large Aperture Telescope Receiver (ApJS (2021) 256: 23 DOI: 10.3847/1538-4365/ac0db7)

Author

Zhu N., Zhu, N, Bhandarkar, T, Coppi, G, Kofman, A, Orlowski-Scherer, J, Xu, Z, Adachi, S, Ade, P, Aiola, S, Austermann, J, Bazarko, A, Beall, J, Bhimani, S, Bond, J, Chesmore, G, Choi, S, Connors, J, Cothard, N, Devlin, M, Dicker, S, Dober, B, Duell, C, Duff, S, Dunner, R, Fabbian, G, Galitzki, N, Gallardo, P, Golec, J, Haridas, S, Harrington, K, Healy, E, Patty Ho, S, Huber, Z, Hubmayr, J, Iuliano, J, Johnson, B, Keating, B, Kiuchi, K, Koopman, B, Lashner, J, Lee, A, Li, Y, Limon, M, Link, M, Lucas, T, Mccarrick, H, Moore, J, Nati, F, Newburgh, L, Niemack, M, Pierpaoli, E, Randall, M, Sarmiento, K, Saunders, L, Seibert, J, Sierra, C, Sonka, R, Spisak, J, Sutariya, S, Tajima, O, Teply, G, Thornton, R, Tsan, T, Tucker, C, Ullom, J, Vavagiakis, E, Vissers, M, Walker, S, Westbrook, B, Wollack, E, Zannoni, M, Zhu N., Bhandarkar T., Coppi G., Kofman A. M., Orlowski-Scherer J. L., Xu Z., Adachi S., Ade P., Aiola S., Austermann J., Bazarko A. O., Beall J. A., Bhimani S., Bond J. R., Chesmore G. E., Choi S. K., Connors J., Cothard N. F., Devlin M., Dicker S., Dober B., Duell C. J., Duff S. M., Dunner R., Fabbian G., Galitzki N., Gallardo P. A., Golec J. E., Haridas S. K., Harrington K., Healy E., Patty Ho S. -P., Huber Z. B., Hubmayr J., Iuliano J., Johnson B. R., Keating B., Kiuchi K., Koopman B. J., Lashner J., Lee A. T., Li Y., Limon M., Link M., Lucas T. J., McCarrick H., Moore J., Nati F., Newburgh L. B., Niemack M. D., Pierpaoli E., Randall M. J., Sarmiento K. P., Saunders L. J., Seibert J., Sierra C., Sonka R., Spisak J., Sutariya S., Tajima O., Teply G. P., Thornton R. J., Tsan T., Tucker C., Ullom J., Vavagiakis E. M., Vissers M. R., Walker S., Westbrook B., Wollack E. J., Zannoni M., Zhu N., Zhu, N, Bhandarkar, T, Coppi, G, Kofman, A, Orlowski-Scherer, J, Xu, Z, Adachi, S, Ade, P, Aiola, S, Austermann, J, Bazarko, A, Beall, J, Bhimani, S, Bond, J, Chesmore, G, Choi, S, Connors, J, Cothard, N, Devlin, M, Dicker, S, Dober, B, Duell, C, Duff, S, Dunner, R, Fabbian, G, Galitzki, N, Gallardo, P, Golec, J, Haridas, S, Harrington, K, Healy, E, Patty Ho, S, Huber, Z, Hubmayr, J, Iuliano, J, Johnson, B, Keating, B, Kiuchi, K, Koopman, B, Lashner, J, Lee, A, Li, Y, Limon, M, Link, M, Lucas, T, Mccarrick, H, Moore, J, Nati, F, Newburgh, L, Niemack, M, Pierpaoli, E, Randall, M, Sarmiento, K, Saunders, L, Seibert, J, Sierra, C, Sonka, R, Spisak, J, Sutariya, S, Tajima, O, Teply, G, Thornton, R, Tsan, T, Tucker, C, Ullom, J, Vavagiakis, E, Vissers, M, Walker, S, Westbrook, B, Wollack, E, Zannoni, M, Zhu N., Bhandarkar T., Coppi G., Kofman A. M., Orlowski-Scherer J. L., Xu Z., Adachi S., Ade P., Aiola S., Austermann J., Bazarko A. O., Beall J. A., Bhimani S., Bond J. R., Chesmore G. E., Choi S. K., Connors J., Cothard N. F., Devlin M., Dicker S., Dober B., Duell C. J., Duff S. M., Dunner R., Fabbian G., Galitzki N., Gallardo P. A., Golec J. E., Haridas S. K., Harrington K., Healy E., Patty Ho S. -P., Huber Z. B., Hubmayr J., Iuliano J., Johnson B. R., Keating B., Kiuchi K., Koopman B. J., Lashner J., Lee A. T., Li Y., Limon M., Link M., Lucas T. J., McCarrick H., Moore J., Nati F., Newburgh L. B., Niemack M. D., Pierpaoli E., Randall M. J., Sarmiento K. P., Saunders L. J., Seibert J., Sierra C., Sonka R., Spisak J., Sutariya S., Tajima O., Teply G. P., Thornton R. J., Tsan T., Tucker C., Ullom J., Vavagiakis E. M., Vissers M. R., Walker S., Westbrook B., Wollack E. J., and Zannoni M.

Abstract

After the publication of the article, it was brought to our attention that the description of Equation (1) may cause potential confusion. Thus, we have decided to provide a newer reference and added a unit for qtot in the description. The updated paragraph should read as the following:.

Published
2021

20. Simons Observatory HoloSim-ML: Machine learning applied to the efficient analysis of radio holography measurements of complex optical systems

Author

Chesmore, G, Adler, A, Cothard, N, Dachlythra, N, Gallardo, P, Gudmundsson, J, Johnson, B, Limon, M, Mcmahon, J, Nati, F, Niemack, M, Puglisi, G, Simon, S, Wollack, E, Wolz, K, Xu, Z, Zhu, N, Chesmore G. E., Adler A. E., Cothard N. F., Dachlythra N., Gallardo P. A., Gudmundsson J., Johnson B. R., Limon M., McMahon J., Nati F., Niemack M. D., Puglisi G., Simon S. M., Wollack E. J., Wolz K., Xu Z., Zhu N., Chesmore, G, Adler, A, Cothard, N, Dachlythra, N, Gallardo, P, Gudmundsson, J, Johnson, B, Limon, M, Mcmahon, J, Nati, F, Niemack, M, Puglisi, G, Simon, S, Wollack, E, Wolz, K, Xu, Z, Zhu, N, Chesmore G. E., Adler A. E., Cothard N. F., Dachlythra N., Gallardo P. A., Gudmundsson J., Johnson B. R., Limon M., McMahon J., Nati F., Niemack M. D., Puglisi G., Simon S. M., Wollack E. J., Wolz K., Xu Z., and Zhu N.

Abstract

Near-field radio holography is a common method for measuring and aligning mirror surfaces for millimeter and sub-millimeter telescopes. In instruments with more than a single mirror, degeneracies arise in the holography measurement, requiring multiple measurements and new fitting methods. We present HoloSim-ML, a Python code for beam simulation and analysis of radio holography data from complex optical systems. This code uses machine learning to efficiently determine the position of hundreds of mirror adjusters on multiple mirrors with few micrometer accuracy. We apply this approach to the example of the Simons Observatory 6 m telescope.

Published
2021

21. The Atacama Cosmology Telescope: Probing the baryon content of SDSS DR15 galaxies with the thermal and kinematic Sunyaev-Zel’dovich effects

Author

Vavagiakis, E, Gallardo, P, Calafut, V, Amodeo, S, Aiola, S, Austermann, J, Battaglia, N, Battistelli, E, Beall, J, Bean, R, Bond, J, Calabrese, E, Choi, S, Cothard, N, Devlin, M, Duell, C, Duff, S, Duivenvoorden, A, Dunkley, J, Dunner, R, Ferraro, S, Guan, Y, Hill, J, Hilton, G, Hilton, M, Hlozek, R, Huber, Z, Hubmayr, J, Huffenberger, K, Hughes, J, Koopman, B, Kosowsky, A, Li, Y, Lokken, M, Madhavacheril, M, Mcmahon, J, Moodley, K, Naess, S, Nati, F, Newburgh, L, Niemack, M, Page, L, Partridge, B, Schaan, E, Schillaci, A, Sifon, C, Spergel, D, Staggs, S, Ullom, J, Vale, L, Van Engelen, A, Van Lanen, J, Wollack, E, Xu, Z, Vavagiakis E. M., Gallardo P. A., Calafut V., Amodeo S., Aiola S., Austermann J. E., Battaglia N., Battistelli E. S., Beall J. A., Bean R., Bond J. R., Calabrese E., Choi S. K., Cothard N. F., Devlin M. J., Duell C. J., Duff S. M., Duivenvoorden A. J., Dunkley J., Dunner R., Ferraro S., Guan Y., Hill J. C., Hilton G. C., Hilton M., Hlozek R., Huber Z. B., Hubmayr J., Huffenberger K. M., Hughes J. P., Koopman B. J., Kosowsky A., Li Y., Lokken M., Madhavacheril M., McMahon J., Moodley K., Naess S., Nati F., Newburgh L. B., Niemack M. D., Page L. A., Partridge B., Schaan E., Schillaci A., Sifon C., Spergel D. N., Staggs S. T., Ullom J. N., Vale L. R., Van Engelen A., Van Lanen J., Wollack E. J., Xu Z., Vavagiakis, E, Gallardo, P, Calafut, V, Amodeo, S, Aiola, S, Austermann, J, Battaglia, N, Battistelli, E, Beall, J, Bean, R, Bond, J, Calabrese, E, Choi, S, Cothard, N, Devlin, M, Duell, C, Duff, S, Duivenvoorden, A, Dunkley, J, Dunner, R, Ferraro, S, Guan, Y, Hill, J, Hilton, G, Hilton, M, Hlozek, R, Huber, Z, Hubmayr, J, Huffenberger, K, Hughes, J, Koopman, B, Kosowsky, A, Li, Y, Lokken, M, Madhavacheril, M, Mcmahon, J, Moodley, K, Naess, S, Nati, F, Newburgh, L, Niemack, M, Page, L, Partridge, B, Schaan, E, Schillaci, A, Sifon, C, Spergel, D, Staggs, S, Ullom, J, Vale, L, Van Engelen, A, Van Lanen, J, Wollack, E, Xu, Z, Vavagiakis E. M., Gallardo P. A., Calafut V., Amodeo S., Aiola S., Austermann J. E., Battaglia N., Battistelli E. S., Beall J. A., Bean R., Bond J. R., Calabrese E., Choi S. K., Cothard N. F., Devlin M. J., Duell C. J., Duff S. M., Duivenvoorden A. J., Dunkley J., Dunner R., Ferraro S., Guan Y., Hill J. C., Hilton G. C., Hilton M., Hlozek R., Huber Z. B., Hubmayr J., Huffenberger K. M., Hughes J. P., Koopman B. J., Kosowsky A., Li Y., Lokken M., Madhavacheril M., McMahon J., Moodley K., Naess S., Nati F., Newburgh L. B., Niemack M. D., Page L. A., Partridge B., Schaan E., Schillaci A., Sifon C., Spergel D. N., Staggs S. T., Ullom J. N., Vale L. R., Van Engelen A., Van Lanen J., Wollack E. J., and Xu Z.

Abstract

We present measurements of the average thermal Sunyaev Zel’dovich (tSZ) effect from optically selected galaxy groups and clusters at high signal-to-noise (up to ) and estimate their baryon content within a radius aperture. Sources from the Sloan Digital Sky Survey Baryon Oscillation Spectroscopic Survey 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 Planck data (ACT DR4). The corresponding optical depths , which depend on the baryon content of the halos, are estimated using results from cosmological hydrodynamic simulations assuming an active galactic nuclei feedback radiative cooling model. We estimate the mean mass of the halos in multiple luminosity bins, and compare the tSZ-based estimates to theoretical predictions of the baryon content for a Navarro-Frenk-White profile. We do the same for estimates extracted from fits to pairwise baryon momentum measurements of the kinematic Sunyaev-Zel’dovich effect (kSZ) for the same dataset obtained in a companion paper. We find that the estimates from the tSZ measurements in this work and the kSZ measurements in the companion paper agree within for two out of the three disjoint luminosity bins studied, while they differ by 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 toward empirical Compton- relationships to provide new tests of cluster formation and evolution models.

Published
2021

22. The Atacama Cosmology Telescope: Microwave Intensity and Polarization Maps of the Galactic Center

Author

Guan, Y, Clark, S, Hensley, B, Gallardo, P, Naess, S, Duell, C, Aiola, S, Atkins, Z, Calabrese, E, Choi, S, Cothard, N, Devlin, M, Duivenvoorden, A, Dunkley, J, Dunner, R, Ferraro, S, Hasselfield, M, Hughes, J, Koopman, B, Kosowsky, A, Madhavacheril, M, Mcmahon, J, Nati, F, Niemack, M, Page, L, Salatino, M, Schaan, E, Sehgal, N, Sifon, C, Staggs, S, Vavagiakis, E, Wollack, E, Xu, Z, Guan Y., Clark S. E., Hensley B. S., Gallardo P. A., Naess S., Duell C. J., Aiola S., Atkins Z., Calabrese E., Choi S. K., Cothard N. F., Devlin M., Duivenvoorden A. J., Dunkley J., Dunner R., Ferraro S., Hasselfield M., Hughes J. P., Koopman B. J., Kosowsky A. B., Madhavacheril M. S., McMahon J., Nati F., Niemack M. D., Page L. A., Salatino M., Schaan E., Sehgal N., Sifon C., Staggs S., Vavagiakis E. M., Wollack E. J., Xu Z., Guan, Y, Clark, S, Hensley, B, Gallardo, P, Naess, S, Duell, C, Aiola, S, Atkins, Z, Calabrese, E, Choi, S, Cothard, N, Devlin, M, Duivenvoorden, A, Dunkley, J, Dunner, R, Ferraro, S, Hasselfield, M, Hughes, J, Koopman, B, Kosowsky, A, Madhavacheril, M, Mcmahon, J, Nati, F, Niemack, M, Page, L, Salatino, M, Schaan, E, Sehgal, N, Sifon, C, Staggs, S, Vavagiakis, E, Wollack, E, Xu, Z, Guan Y., Clark S. E., Hensley B. S., Gallardo P. A., Naess S., Duell C. J., Aiola S., Atkins Z., Calabrese E., Choi S. K., Cothard N. F., Devlin M., Duivenvoorden A. J., Dunkley J., Dunner R., Ferraro S., Hasselfield M., Hughes J. P., Koopman B. J., Kosowsky A. B., Madhavacheril M. S., McMahon J., Nati F., Niemack M. D., Page L. A., Salatino M., Schaan E., Sehgal N., Sifon C., Staggs S., Vavagiakis E. M., Wollack E. J., and Xu Z.

Abstract

We present arcminute-resolution intensity and polarization maps of the Galactic center made with the Atacama Cosmology Telescope. The maps cover a 32 deg2 field at 98, 150, and 224 GHz with |l| ≤ 4 , |b| ≤ 2 . 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.

Published
2021

23. The Atacama Cosmology Telescope: Detection of the pairwise kinematic Sunyaev-Zel’dovich effect with SDSS DR15 galaxies ()

Author

Calafut, V, Gallardo, P, Vavagiakis, E, Amodeo, S, Aiola, S, Austermann, J, Battaglia, N, Battistelli, E, Beall, J, Bean, R, Bond, J, Calabrese, E, Choi, S, Cothard, N, Devlin, M, Duell, C, Duff, S, Duivenvoorden, A, Dunkley, J, Dunner, R, Ferraro, S, Guan, Y, Hill, J, Hilton, G, Hilton, M, Hlozek, R, Huber, Z, Hubmayr, J, Huffenberger, K, Hughes, J, Koopman, B, Kosowsky, A, Li, Y, Lokken, M, Madhavacheril, M, Mcmahon, J, Moodley, K, Naess, S, Nati, F, Newburgh, L, Niemack, M, Page, L, Partridge, B, Schaan, E, Schillaci, A, Sifon, C, Spergel, D, Staggs, S, Ullom, J, Vale, L, Van Engelen, A, Van Lanen, J, Wollack, E, Xu, Z, Calafut V., Gallardo P. A., Vavagiakis E. M., Amodeo S., Aiola S., Austermann J. E., Battaglia N., Battistelli E. S., Beall J. A., Bean R., Bond J. R., Calabrese E., Choi S. K., Cothard N. F., Devlin M. J., Duell C. J., Duff S. M., Duivenvoorden A. J., Dunkley J., Dunner R., Ferraro S., Guan Y., Hill J. C., Hilton G. C., Hilton M., Hlozek R., Huber Z. B., Hubmayr J., Huffenberger K. M., Hughes J. P., Koopman B. J., Kosowsky A., Li Y., Lokken M., Madhavacheril M., McMahon J., Moodley K., Naess S., Nati F., Newburgh L. B., Niemack M. D., Page L. A., Partridge B., Schaan E., Schillaci A., Sifon C., Spergel D. N., Staggs S. T., Ullom J. N., Vale L. R., Van Engelen A., Van Lanen J., Wollack E. J., Xu Z., Calafut, V, Gallardo, P, Vavagiakis, E, Amodeo, S, Aiola, S, Austermann, J, Battaglia, N, Battistelli, E, Beall, J, Bean, R, Bond, J, Calabrese, E, Choi, S, Cothard, N, Devlin, M, Duell, C, Duff, S, Duivenvoorden, A, Dunkley, J, Dunner, R, Ferraro, S, Guan, Y, Hill, J, Hilton, G, Hilton, M, Hlozek, R, Huber, Z, Hubmayr, J, Huffenberger, K, Hughes, J, Koopman, B, Kosowsky, A, Li, Y, Lokken, M, Madhavacheril, M, Mcmahon, J, Moodley, K, Naess, S, Nati, F, Newburgh, L, Niemack, M, Page, L, Partridge, B, Schaan, E, Schillaci, A, Sifon, C, Spergel, D, Staggs, S, Ullom, J, Vale, L, Van Engelen, A, Van Lanen, J, Wollack, E, Xu, Z, Calafut V., Gallardo P. A., Vavagiakis E. M., Amodeo S., Aiola S., Austermann J. E., Battaglia N., Battistelli E. S., Beall J. A., Bean R., Bond J. R., Calabrese E., Choi S. K., Cothard N. F., Devlin M. J., Duell C. J., Duff S. M., Duivenvoorden A. J., Dunkley J., Dunner R., Ferraro S., Guan Y., Hill J. C., Hilton G. C., Hilton M., Hlozek R., Huber Z. B., Hubmayr J., Huffenberger K. M., Hughes J. P., Koopman B. J., Kosowsky A., Li Y., Lokken M., Madhavacheril M., McMahon J., Moodley K., Naess S., Nati F., Newburgh L. B., Niemack M. D., Page L. A., Partridge B., Schaan E., Schillaci A., Sifon C., Spergel D. N., Staggs S. T., Ullom J. N., Vale L. R., Van Engelen A., Van Lanen J., Wollack E. J., and Xu Z.

Abstract

We present a detection of the pairwise kinematic Sunyaev-Zeldovich (kSZ) effect using Atacama Cosmology Telescope (ACT) and 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 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.

Published
2021

24. Characterization of Transition Edge Sensors for the Simons Observatory

Author

Stevens, J, Cothard, N, Vavagiakis, E, Ali, A, Arnold, K, Austermann, J, Choi, S, Dober, B, Duell, C, Duff, S, Hilton, G, Ho, S, Hoang, T, Hubmayr, J, Lee, A, Mangu, A, Nati, F, Niemack, M, Raum, C, Renzullo, M, Salatino, M, Sasse, T, Simon, S, Staggs, S, Suzuki, A, Truitt, P, Ullom, J, Vivalda, J, Vissers, M, Walker, S, Westbrook, B, Wollack, E, Xu, Z, Yohannes, D, Stevens J. R., Cothard N. F., Vavagiakis E. M., Ali A., Arnold K., Austermann J. E., Choi S. K., Dober B. J., Duell C., Duff S. M., Hilton G. C., Ho S. -P. P., Hoang T. D., Hubmayr J., Lee A. T., Mangu A., Nati F., Niemack M. D., Raum C., Renzullo M., Salatino M., Sasse T., Simon S. M., Staggs S., Suzuki A., Truitt P., Ullom J., Vivalda J., Vissers M. R., Walker S., Westbrook B., Wollack E. J., Xu Z., Yohannes D., Stevens, J, Cothard, N, Vavagiakis, E, Ali, A, Arnold, K, Austermann, J, Choi, S, Dober, B, Duell, C, Duff, S, Hilton, G, Ho, S, Hoang, T, Hubmayr, J, Lee, A, Mangu, A, Nati, F, Niemack, M, Raum, C, Renzullo, M, Salatino, M, Sasse, T, Simon, S, Staggs, S, Suzuki, A, Truitt, P, Ullom, J, Vivalda, J, Vissers, M, Walker, S, Westbrook, B, Wollack, E, Xu, Z, Yohannes, D, Stevens J. R., Cothard N. F., Vavagiakis E. M., Ali A., Arnold K., Austermann J. E., Choi S. K., Dober B. J., Duell C., Duff S. M., Hilton G. C., Ho S. -P. P., Hoang T. D., Hubmayr J., Lee A. T., Mangu A., Nati F., Niemack M. D., Raum C., Renzullo M., Salatino M., Sasse T., Simon S. M., Staggs S., Suzuki A., Truitt P., Ullom J., Vivalda J., Vissers M. R., Walker S., Westbrook B., Wollack E. J., Xu Z., and Yohannes D.

Abstract

The Simons Observatory is building both large (6 m) and small (0.5 m) aperture telescopes in the Atacama Desert in Chile to observe the cosmic microwave background CMB radiation with unprecedented sensitivity. Simons Observatory telescopes in total will use over 60,000 transition edge sensor (TES) detectors spanning center frequencies between 27 and 285 GHz and operating near 100 mK. TES devices have been fabricated for the Simons Observatory by NIST, Berkeley, and HYPRES/SeeQC corporation. Iterations of these devices have been tested cryogenically in order to inform the fabrication of further devices, which will culminate in the final TES designs to be deployed in the field. The detailed design specifications have been independently iterated at each fabrication facility for particular detector frequencies. We present test results for prototype devices, with emphasis on NIST high frequency detectors. A dilution refrigerator was used to achieve the required temperatures. Measurements were taken both with 4-lead resistance measurements and with a time-domain Superconducting Quantum Interference Device (SQUID) multiplexer system. The SQUID readout measurements include analysis of current versus voltage (IV) curves at various temperatures, square wave bias step measurements, and detector noise measurements. Normal resistance, superconducting critical temperature, saturation power, thermal and natural time constants, and thermal properties of the devices are extracted from these measurements.

Published
2020

26. Advanced ACTPol Low-Frequency Array: Readout and Characterization of Prototype 27 and 39 GHz Transition Edge Sensors

Author

Koopman, B, Cothard, N, Choi, S, Crowley, K, Duff, S, Henderson, S, Ho, S, Hubmayr, J, Gallardo, P, Nati, F, Niemack, M, Simon, S, Staggs, S, Stevens, J, Vavagiakis, E, Wollack, E, Koopman B. J., Cothard N. F., Choi S. K., Crowley K. T., Duff S. M., Henderson S. W., Ho S. P., Hubmayr J., Gallardo P. A., Nati F., Niemack M. D., Simon S. M., Staggs S. T., Stevens J. R., Vavagiakis E. M., Wollack E. J., Koopman, B, Cothard, N, Choi, S, Crowley, K, Duff, S, Henderson, S, Ho, S, Hubmayr, J, Gallardo, P, Nati, F, Niemack, M, Simon, S, Staggs, S, Stevens, J, Vavagiakis, E, Wollack, E, Koopman B. J., Cothard N. F., Choi S. K., Crowley K. T., Duff S. M., Henderson S. W., Ho S. P., Hubmayr J., Gallardo P. A., Nati F., Niemack M. D., Simon S. M., Staggs S. T., Stevens J. R., Vavagiakis E. M., and Wollack E. J.

Abstract

Advanced ACTPol (AdvACT) is a third-generation polarization upgrade to the Atacama Cosmology Telescope, designed to observe the cosmic microwave background (CMB). AdvACT expands on the 90 and 150 GHz transition edge sensor (TES) bolometer arrays of the ACT Polarimeter (ACTPol), adding both high-frequency (HF, 150/230 GHz) and low-frequency (LF, 27/39 GHz) multichroic arrays. The addition of the high- and low-frequency detectors allows for the characterization of synchrotron and spinning dust emission at the low frequencies and foreground emission from galactic dust and dusty star-forming galaxies at the high frequencies. The increased spectral coverage of AdvACT will enable a wide range of CMB science, such as improving constraints on dark energy, the sum of the neutrino masses, and the existence of primordial gravitational waves. The LF array will be the final AdvACT array, replacing one of the MF arrays for a single season. Prior to the fabrication of the final LF detector array, we designed and characterized prototype TES bolometers. Detector geometries in these prototypes are varied in order to inform and optimize the bolometer designs for the LF array, which requires significantly lower noise levels and saturation powers (as low as ∼1 pW) than the higher-frequency detectors. Here we present results from tests of the first LF prototype TES detectors for AdvACT, including measurements of the saturation power, critical temperature, thermal conductance, and time constants. We also describe the modifications to the time-division SQUID readout architecture compared to the MF and HF arrays.

Published
2018

27. Magnetic Sensitivity of AlMn TESes and Shielding Considerations for Next-Generation CMB Surveys

Author

Vavagiakis, E, Henderson, S, Zheng, K, Cho, H, Cothard, N, Dober, B, Duff, S, Gallardo, P, Hilton, G, Hubmayr, J, Irwin, K, Koopman, B, Li, D, Nati, F, Niemack, M, Reintsema, C, Simon, S, Stevens, J, Suzuki, A, Westbrook, B, Vavagiakis E. M., Henderson S. W., Zheng K., Cho H. -M., Cothard N. F., Dober B., Duff S. M., Gallardo P. A., Hilton G., Hubmayr J., Irwin K. D., Koopman B. J., Li D., Nati F., Niemack M. D., Reintsema C. D., Simon S., Stevens J. R., SUZUKI, AKANE, Westbrook B., Vavagiakis, E, Henderson, S, Zheng, K, Cho, H, Cothard, N, Dober, B, Duff, S, Gallardo, P, Hilton, G, Hubmayr, J, Irwin, K, Koopman, B, Li, D, Nati, F, Niemack, M, Reintsema, C, Simon, S, Stevens, J, Suzuki, A, Westbrook, B, Vavagiakis E. M., Henderson S. W., Zheng K., Cho H. -M., Cothard N. F., Dober B., Duff S. M., Gallardo P. A., Hilton G., Hubmayr J., Irwin K. D., Koopman B. J., Li D., Nati F., Niemack M. D., Reintsema C. D., Simon S., Stevens J. R., SUZUKI, AKANE, and Westbrook B.

Abstract

In the next decade, new ground-based cosmic microwave background (CMB) experiments such as Simons Observatory, CCAT-prime, and CMB-S4 will increase the number of detectors observing the CMB by an order of magnitude or more, dramatically improving our understanding of cosmology and astrophysics. These projects will deploy receivers with as many as hundreds of thousands of transition edge sensor (TES) bolometers coupled to superconducting quantum interference device (SQUID)-based readout systems. It is well known that superconducting devices such as TESes and SQUIDs are sensitive to magnetic fields. However, the effects of magnetic fields on TESes are not easily predicted due to the complex behavior of the superconducting transition, which motivates direct measurements of the magnetic sensitivity of these devices. We present comparative four-lead measurements of the critical temperature versus applied magnetic field of AlMn TESes varying in geometry, doping, and leg length, including Advanced ACT and POLARBEAR-2/Simons Array bolometers. MoCu ACTPol TESes are also tested and are found to be more sensitive to magnetic fields than the AlMn devices. We present an observation of weak-link-like behavior in AlMn TESes at low critical currents. We also compare measurements of magnetic sensitivity for time division multiplexing SQUIDs and frequency division multiplexing microwave rf-SQUIDs. We discuss the implications of our measurements on the magnetic shielding required for future experiments that aim to map the CMB to near-fundamental limits.

Published
2018

28. The Advanced ACTPol 27/39 GHz Array

Author

Simon, S, Beall, J, Cothard, N, Duff, S, Gallardo, P, Ho, S, Hubmayr, J, Koopman, B, Mcmahon, J, Nati, F, Niemack, M, Staggs, S, Vavagiakis, E, Wollack, E, Simon S. M., Beall J. A., Cothard N. F., Duff S. M., Gallardo P. A., Ho S. P., Hubmayr J., Koopman B. J., McMahon J. J., Nati F., Niemack M. D., Staggs S. T., Vavagiakis E. M., Wollack E. J., Simon, S, Beall, J, Cothard, N, Duff, S, Gallardo, P, Ho, S, Hubmayr, J, Koopman, B, Mcmahon, J, Nati, F, Niemack, M, Staggs, S, Vavagiakis, E, Wollack, E, Simon S. M., Beall J. A., Cothard N. F., Duff S. M., Gallardo P. A., Ho S. P., Hubmayr J., Koopman B. J., McMahon J. J., Nati F., Niemack M. D., Staggs S. T., Vavagiakis E. M., and Wollack E. J.

Abstract

Advanced ACTPol (AdvACT) will observe the temperature and polarization of the cosmic microwave background (CMB) at multiple frequencies and high resolution to place improved constraints on inflation, dark matter, and dark energy. Foregrounds from synchrotron and dust radiation are a source of contamination that must be characterized and removed across a wide range of frequencies. AdvACT will thus observe at five frequency bands from 27 to 230 GHz. We discuss the design of the pixels and feedhorns for the 27/39 GHz multichroic array for AdvACT, which will target the synchrotron radiation that dominates at these frequencies. To gain 35% in mapping speed in the 39 GHz band where the foreground signals are faintest, the pixel number was increased through reducing the pixel diameter to 1.08 lambda at the lowest frequency, which represents a 22% decrease in size compared to our previously most tightly packed pixels.

Published
2018

30. Prime-Cam: a first-light instrument for the CCAT-prime telescope

Author

Zmuidzinas, Jonas, Gao, Jian-Rong, Vavagiakis, E. M., Ahmed, Z., Ali, A., Basu, K., Battaglia, N., Bertoldi, F., Bond, R., Bustos, R., Chapman, S. C., Chung, D., Coppi, G., Cothard, N. F., Dicker, S., Duell, C. J., Duff, S. M., Erler, J., Fich, M., Galitzki, N., Gallardo, P. A., Henderson, S. W., Herter, T. L., Hilton, G., Hubmayr, J., Irwin, K. D., Koopman, B. J., McMahon, J., Murray, N., Niemack, M. D., Nikola, T., Nolta, M., Orlowski-Scherer, J., Parshley, S. C., Riechers, D. A., Rossi, K., Scott, D., Sierra, C., Silva-Feaver, M., Simon, S. M., Stacey, G. J., Stevens, J. R., Ullom, J. N., Vissers, M. R., Walker, S., Wollack, E. J., Xu, Z., and Zhu, N.

Published
2018
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results