Browsing by Author "Devlin, Mark"

Now showing 1 - 8 of 8
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    Atacama Cosmology Telescope: Modeling the gas thermodynamics in BOSS CMASS galaxies from kinematic and thermal Sunyaev-Zel'dovich measurements
    (2021) Amodeo, Stefania; Battaglia, Nicholas; Schaan, Emmanuel; Ferraro, Simone; Moser, Emily; Aiola, Simone; Austermann, Jason E.; Beall, James A.; Bean, Rachel; Becker, Daniel T.; Bond, Richard J.; Calabrese, Erminia; Calafut, Victoria; Choi, Steve K.; Denison, Edward, V; Devlin, Mark; Duff, Shannon M.; Duivenvoorden, Adriaan J.; Dunkley, Jo; Dunner, Rolando; Gallardo, Patricio A.; Hall, Kirsten R.; Han, Dongwon; Hill, J. Colin; Hilton, Gene C.; Hilton, Matt; Hlozek, Renee; Hubmayr, Johannes; Huffenberger, Kevin M.; Hughes, John P.; Koopman, Brian J.; MacInnis, Amanda; McMahon, Jeff; Madhavacheril, Mathew S.; Moodley, Kavilan; Mroczkowski, Tony; Naess, Sigurd; Nati, Federico; Newburgh, Laura B.; Niemack, Michael D.; Page, Lyman A.; Partridge, Bruce; Schillaci, Alessandro; Sehgal, Neelima; Sifon, Cristobal; Spergel, David N.; Staggs, Suzanne; Storer, Emilie R.; Ullom, Joel N.; Vale, Leila R.; van Engelen, Alexander; Van Lanen, Jeff; Vavagiakis, Eve M.; Wollack, Edward J.; Xu, Zhilei
    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 epsilon M.c(2) , where M-* is the stellar mass, to be epsilon = (40 +/- 9) x 10(-6) , and the amplitude of the nonthermal pressure profile to be alpha(Nth) < 0.2(2 sigma), 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)] 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.
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    The Atacama Cosmology Telescope: arcminute-resolution maps of 18 000 square degrees of the microwave sky from ACT 2008-2018 data combined with Planck
    (2020) Naess, Sigurd; Aiola, Simone; Austermann, Jason E.; Battaglia, Nick; Beall, James A.; Becker, Daniel T.; Bond, Richard J.; Calabrese, Erminia; Choi, Steve K.; Cothard, Nicholas F.; Crowley, Kevin T.; Darwish, Omar; Datta, Rahul; Denison, Edward, V; Devlin, Mark; Duell, Cody J.; Duff, Shannon M.; Duivenvoorden, Adriaan J.; Dunkley, Jo; Duenner, Rolando; Fox, Anna E.; Gallardo, Patricio A.; Halpern, Mark; Han, Dongwon; Hasselfield, Matthew; Hill, J. Colin; Hilton, Gene C.; Hilton, Matt; Hincks, Adam D.; Hlozek, Renee; Ho, Shuay-Pwu Patty; Hubmayr, Johannes; Huffenberger, Kevin; Hughes, John P.; Kosowsky, Arthur B.; Louis, Thibaut; Madhavacheril, Mathew S.; McMahon, Jeff; Moodley, Kavilan; Nati, Federico; Nibarger, John P.; Niemack, Michael D.; Page, Lyman; Partridge, Bruce; Salatino, Maria; Schaan, Emmanuel; Schillaci, Alessandro; Schmitt, Benjamin; Sherwin, Blake D.; Sehgal, Neelima; Sifon, Cristobal; Spergel, David; Staggs, Suzanne; Stevens, Jason; Storer, Emilie; Ullom, Joel N.; Vale, Leila R.; Van Engelen, Alexander; Van Lanen, Jeff; Vavagiakis, Eve M.; Wollack, Edward J.; Xu, Zhilei
    This paper presents a maximum-likelihood algorithm for combining sky maps with disparate sky coverage, angular resolution and spatially varying anisotropic noise into a single map of the sky. We use this to merge hundreds of individual maps covering the 2008-2018 ACT observing seasons, resulting in by far the deepest ACT maps released so far. We also combine the maps with the full Planck maps, resulting in maps that have the best features of both Planck and ACT: Planck's nearly white noise on intermediate and large angular scales and ACT's high-resolution and sensitivity on small angular scales. The maps cover over 18 000 square degrees, nearly half the full sky, at 100, 150 and 220 GHz. They reveal 4 000 optically-confirmed clusters through the Sunyaev Zel'dovich effect (SZ) and 18 500 point source candidates at > 5 sigma, the largest single collection of SZ clusters and millimeter wave sources to date. The multi-frequency maps provide millimeter images of nearby galaxies and individual Milky Way nebulae, and even clear detections of several nearby stars. Other anticipated uses of these maps include, for example, thermal SZ and kinematic SZ cluster stacking, CMB cluster lensing and galactic dust science. The method itself has negligible bias. However, due to the preliminary nature of some of the component data sets, we caution that these maps should not be used for precision cosmological analysis. The maps are part of ACT DR5, and will be made available on LAMBDA no later than three months after the journal publication of this article, along with an interactive sky atlas.
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    The Atacama Cosmology Telescope: Detection of Millimeter-wave Transient Sources
    (2021) Naess, Sigurd; Battaglia, Nick; Bond, J. Richard; Calabrese, Erminia; Choi, Steve K.; Cothard, Nicholas F.; Devlin, Mark; Duell, Cody J.; Duivenvoorden, Adriaan J.; Dunkley, Jo; Dunner, Rolando; Gallardo, Patricio A.; Gralla, Megan; Guan, Yilun; Halpern, Mark; Hill, J. Colin; Hilton, Matt; Huffenberger, Kevin M.; Koopman, Brian J.; Kosowsky, Arthur B.; Madhavacheril, Mathew S.; McMahon, Jeff; Nati, Federico; Niemack, Michael D.; Page, Lyman; Partridge, Bruce; Salatino, Maria; Sehgal, Neelima; Spergel, David; Staggs, Suzanne; Wollack, Edward J.; Xu, Zhilei
    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 similar to 50 sigma 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, alpha = 1.5 +/- 0.2. The second, detected at R.A. = 105.1584, decl. = -11.2434 at similar to 20 sigma 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, alpha = 1.8 +/- 0.2. The third, detected at R.A. = 301.9952, decl. = 16.1652 at similar to 40 sigma 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 alpha = -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.
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    The Atacama Cosmology Telescope: Microwave Intensity and Polarization Maps of the Galactic Center
    (2021) Guan, Yilun; Clark, Susan E.; Hensley, Brandon S.; Gallardo, Patricio A.; Naess, Sigurd; Duell, Cody J.; Aiola, Simone; Atkins, Zachary; Calabrese, Erminia; Choi, Steve K.; Cothard, Nicholas F.; Devlin, Mark; Duivenvoorden, Adriaan J.; Dunkley, Jo; Dunner, Rolando; Ferraro, Simone; Hasselfield, Matthew; Hughes, John P.; Koopman, Brian J.; Kosowsky, Arthur B.; Madhavacheril, Mathew S.; McMahon, Jeff; Nati, Federico; Niemack, Michael D.; Page, Lyman A.; Salatino, Maria; Schaan, Emmanuel; Sehgal, Neelima; Sifon, Cristobal; Staggs, Suzanne; Vavagiakis, Eve M.; Wollack, Edward J.; Xu, Zhilei
    We present arcminute-resolution intensity and polarization maps of the Galactic center made with the Atacama Cosmology Telescope. The maps cover a 32 deg(2) field at 98, 150, and 224 GHz with divide l divide <= 4 degrees, divide b divide <= 2 degrees. 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.
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    The Atacama Cosmology Telescope: Millimeter Observations of a Population of Asteroids or: ACTeroids
    (2024) Orlowski-Scherer, John; Venterea, Ricco C.; Battaglia, Nicholas; Naess, Sigurd; Bhandarkar, Tanay; Biermann, Emily; Calabrese, Erminia; Devlin, Mark; Dunkley, Jo; Hervias-Caimapo, Carlos; Gallardo, Patricio A.; Hilton, Matt; Hincks, Adam D.; Knowles, Kenda; Li, Yaqiong; Mcmahon, Jeffrey J.; Niemack, Michael D.; Page, Lyman A.; Partridge, Bruce; Salatino, Maria; Sievers, Jonathan; Sifon, Cristobal; Staggs, Suzanne; van Engelen, Alexander; Vargas, Cristian; Vavagiakis, Eve M.; Wollack, Edward J.
    We present fluxes and light curves for a population of asteroids at millimeter wavelengths, detected by the Atacama Cosmology Telescope (ACT) over 18,000 deg2 of the sky using data from 2017 to 2021. We utilize high cadence maps, which can be used in searching for moving objects such as asteroids and trans-Neptunian Objects, as well as for studying transients. We detect 170 asteroids with a signal-to-noise of at least 5 in at least one of the ACT observing bands, which are centered near 90, 150, and 220 GHz. For each asteroid, we compare the ACT measured flux to predicted fluxes from the near-Earth asteroid thermal model fit to WISE data. We confirm previous results that detected a deficit of flux at millimeter wavelengths. Moreover, we report a spectral characteristic to this deficit, such that the flux is relatively lower at 150 and 220 GHz than at 90 GHz. Additionally, we find that the deficit in flux is greater for S-type asteroids than for C-type.
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    The Atacama Cosmology Telescope: Systematic Transient Search of 3 Day Maps
    (2023) Li, Yaqiong; Biermann, Emily; Naess, Sigurd; Aiola, Simone; An, Rui; Battaglia, Nicholas; Bhandarkar, Tanay; Calabrese, Erminia; Choi, Steve K.; Crowley, Kevin T.; Devlin, Mark; Duell, Cody J.; Duff, Shannon M.; Dunkley, Jo; Dunner, Rolando; Gallardo, Patricio A.; Guan, Yilun; Hervias-Caimapo, Carlos; Hincks, Adam D.; Hubmayr, Johannes; Huffenberger, Kevin M.; Hughes, John P.; Kosowsky, Arthur; Louis, Thibaut; Mallaby-Kay, Maya; Mcmahon, Jeff; Nati, Federico; Niemack, Michael D.; Orlowski-Scherer, John; Page, Lyman; Salatino, Maria; Sifon, Cristobal; Staggs, Suzanne T.; Vargas, Cristian; Vavagiakis, Eve M.; Wang, Yuhan; Wollack, Edward J.
    We conduct a systematic search for transients in 3 yr of data (2017-2019) from the Atacama Cosmology Telescope (ACT). ACT covers 40% of the sky at three bands spanning from 77-277 GHz. Analysis of 3 day mean-subtracted sky maps, which were match filtered for point sources, yielded 29 transient detections. Eight of these transients are due to known asteroids, and three others were previously published. Four of these events occur in areas with poor noise models and thus we cannot be confident they are real transients. We are left with 14 new transient events occurring at 11 unique locations. All of these events are associated with either rotationally variable stars or cool stars. Ten events have flat or falling spectra indicating radiation from synchrotron emission. One event has a rising spectrum indicating a different engine for the flare.
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    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.
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    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