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83 results on '"Crawford, T.M."'

1. Neutrino physics from the cosmic microwave background and large scale structure

Author

Abazajian, K.N., Arnold, K., Austermann, J., Benson, B.A., Bischoff, C., Bock, J., Bond, J.R., Borrill, J., Calabrese, E., Carlstrom, J.E., Carvalho, C.S., Chang, C.L., Chiang, H.C., Church, S., Cooray, A., Crawford, T.M., Dawson, K.S., Das, S., Devlin, M.J., Dobbs, M., Dodelson, S., Doré, O., Dunkley, J., Errard, J., Fraisse, A., Gallicchio, J., Halverson, N.W., Hanany, S., Hildebrandt, S.R., Hincks, A., Hlozek, R., Holder, G., Holzapfel, W.L., Honscheid, K., Hu, W., Hubmayr, J., Irwin, K., Jones, W.C., Kamionkowski, M., Keating, B., Keisler, R., Knox, L., Komatsu, E., Kovac, J., Kuo, C.-L., Lawrence, C., Lee, A.T., Leitch, E., Linder, E., Lubin, P., McMahon, J., Miller, A., Newburgh, L., Niemack, M.D., Nguyen, H., Nguyen, H.T., Page, L., Pryke, C., Reichardt, C.L., Ruhl, J.E., Sehgal, N., Seljak, U., Sievers, J., Silverstein, E., Slosar, A., Smith, K.M., Spergel, D., Staggs, S.T., Stark, A., Stompor, R., Vieregg, A.G., Wang, G., Watson, S., Wollack, E.J., Wu, W.L.K., Yoon, K.W., and Zahn, O.

Published
2015
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2. Inflation physics from the cosmic microwave background and large scale structure

Author

Abazajian, K.N., Arnold, K., Austermann, J., Benson, B.A., Bischoff, C., Bock, J., Bond, J.R., Borrill, J., Buder, I., Burke, D.L., Calabrese, E., Carlstrom, J.E., Carvalho, C.S., Chang, C.L., Chiang, H.C., Church, S., Cooray, A., Crawford, T.M., Crill, B.P., Dawson, K.S., Das, S., Devlin, M.J., Dobbs, M., Dodelson, S., Doré, O., Dunkley, J., Feng, J.L., Fraisse, A., Gallicchio, J., Giddings, S.B., Green, D., Halverson, N.W., Hanany, S., Hanson, D., Hildebrandt, S.R., Hincks, A., Hlozek, R., Holder, G., Holzapfel, W.L., Honscheid, K., Horowitz, G., Hu, W., Hubmayr, J., Irwin, K., Jackson, M., Jones, W.C., Kallosh, R., Kamionkowski, M., Keating, B., Keisler, R., Kinney, W., Knox, L., Komatsu, E., Kovac, J., Kuo, C.-L., Kusaka, A., Lawrence, C., Lee, A.T., Leitch, E., Linde, A., Linder, E., Lubin, P., Maldacena, J., Martinec, E., McMahon, J., Miller, A., Mukhanov, V., Newburgh, L., Niemack, M.D., Nguyen, H., Nguyen, H.T., Page, L., Pryke, C., Reichardt, C.L., Ruhl, J.E., Sehgal, N., Seljak, U., Senatore, L., Sievers, J., Silverstein, E., Slosar, A., Smith, K.M., Spergel, D., Staggs, S.T., Stark, A., Stompor, R., Vieregg, A.G., Wang, G., Watson, S., Wollack, E.J., Wu, W.L.K., Yoon, K.W., Zahn, O., and Zaldarriaga, M.

Published
2015
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4. Sunyaev–Zel’dovich effect and X-ray scaling relations from weak lensing mass calibration of 32 South Pole Telescope selected galaxy clusters

Author

MIT Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology. Department of Physics, Dietrich, J.P., Bocquet, S., Schrabback, T., Applegate, D., Hoekstra, H., Grandis, S., Mohr, J.J., Allen, S.W., Bayliss, Matthew B, Benson, B.A., Bleem, L.E., Brodwin, M., Bulbul, Esra, Capasso, R., Chiu, I., Crawford, T.M., Gonzalez, A.H., de Haan, T., Klein, M., von der Linden, A., Mantz, A.B., Marrone, D.P., McDonald, Michael A., Raghunathan, S., Rapetti, D., Reichardt, C.L., Saro, A., Stalder, B., Stark, A., Stern, C., Stubbs, C., MIT Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology. Department of Physics, Dietrich, J.P., Bocquet, S., Schrabback, T., Applegate, D., Hoekstra, H., Grandis, S., Mohr, J.J., Allen, S.W., Bayliss, Matthew B, Benson, B.A., Bleem, L.E., Brodwin, M., Bulbul, Esra, Capasso, R., Chiu, I., Crawford, T.M., Gonzalez, A.H., de Haan, T., Klein, M., von der Linden, A., Mantz, A.B., Marrone, D.P., McDonald, Michael A., Raghunathan, S., Rapetti, D., Reichardt, C.L., Saro, A., Stalder, B., Stark, A., Stern, C., and Stubbs, C.

Abstract

© 2018 The Author(s). Uncertainty in mass-observable scaling relations is currently the limiting factor for galaxycluster-based cosmology. Weak gravitational lensing can provide direct mass calibration and reduce the mass uncertainty. We present new ground-based weak lensing observations of 19 South Pole Telescope (SPT) selected clusters at redshifts 0.29 = z = 0.61 and combine them with previously reported space-based observations of 13 galaxy clusters at redshifts 0.576 = z = 1.132 to constrain the cluster mass scaling relations with the Sunyaev-Zel'dovich effect (SZE), the cluster gas mass Mgas and YX, the product of Mgas and X-ray temperature. We extend a previously used framework for the analysis of scaling relations and cosmological constraints obtained from SPT-selected clusters to make use of weak lensing information. We introduce a new approach to estimate the effective average redshift distribution of background galaxies and quantify a number of systematic errors affecting the weak lensing modelling. These errors include a calibration of the bias incurred by fitting a Navarro-Frenk-White profile to the reduced shear using N-body simulations. We blind the analysis to avoid confirmation bias. We are able to limit the systematic uncertainties to 5.6% in cluster mass (68% confidence). Our constraints on the mass-X-ray observable scaling relation parameters are consistent with those obtained by earlier studies and our constraints for the mass-SZE scaling relation are consistent with the simulation-based prior used in the most recent SPT-SZ cosmology analysis. We can now replace the external mass calibration priors used in previous SPT-SZ cosmology studies with a direct, internal calibration obtained for the same clusters.

Published
2022

5. First M87 Event Horizon Telescope Results. VIII. Magnetic Field Structure near the Event Horizon

Author

Akiyama, K. Algaba, J.C. Alberdi, A. Alef, W. Anantua, R. Asada, K. Azulay, R. Baczko, A.-K. Ball, D. Baloković, M. Barrett, J. Benson, B.A. Bintley, D. Blackburn, L. Blundell, R. Boland, W. Bouman, K.L. Bower, G.C. Boyce, H. Bremer, M. Brinkerink, C.D. Brissenden, R. Britzen, S. Broderick, A.E. Broguiere, D. Bronzwaer, T. Byun, D.-Y. Carlstrom, J.E. Chael, A. Chan, C.-K. Chatterjee, S. Chatterjee, K. Chen, M.-T. Chen, Y. Chesler, P.M. Cho, I. Christian, P. Conway, J.E. Cordes, J.M. Crawford, T.M. Crew, G.B. Cruz-Osorio, A. Cui, Y. Davelaar, J. De Laurentis, M. Deane, R. Dempsey, J. Desvignes, G. Dexter, J. Doeleman, S.S. Eatough, R.P. Falcke, H. Farah, J. Fish, V.L. Fomalont, E. Ford, H.A. Fraga-Encinas, R. Friberg, P. Fromm, C.M. Fuentes, A. Galison, P. Gammie, C.F. Garciá, R. Gelles, Z. Gentaz, O. Georgiev, B. Goddi, C. Gold, R. Gómez, J.L. Gómez-Ruiz, A.I. Gu, M. Gurwell, M. Hada, K. Haggard, D. Hecht, M.H. Hesper, R. Himwich, E. Ho, L.C. Ho, P. Honma, M. Huang, C.-W.L. Huang, L. Hughes, D.H. Ikeda, S. Inoue, M. Issaoun, S. James, D.J. Jannuzi, B.T. Janssen, M. Jeter, B. Jiang, W. Jimenez-Rosales, A. Johnson, M.D. Jorstad, S. Jung, T. Karami, M. Karuppusamy, R. Kawashima, T. Keating, G.K. Kettenis, M. Kim, D.-J. Kim, J.-Y. Kim, J. Kim, J. Kino, M. Koay, J.Y. Kofuji, Y. Koch, P.M. Koyama, S. Kramer, M. Kramer, C. Krichbaum, T.P. Kuo, C.-Y. Lauer, T.R. Lee, S.-S. Levis, A. Li, Y.-R. Li, Z. Lindqvist, M. Lico, R. Lindahl, G. Liu, J. Liu, K. Liuzzo, E. Lo, W.-P. Lobanov, A.P. Loinard, L. Lonsdale, C. Lu, R.-S. Macdonald, N.R. Mao, J. Marchili, N. Markoff, S. Marrone, D.P. Marscher, A.P. Martí-Vidal, I. Matsushita, S. Matthews, L.D. Medeiros, L. Menten, K.M. Mizuno, I. Mizuno, Y. Moran, J.M. Moriyama, K. Moscibrodzka, M. Müller, C. Musoke, G. Mejiás, A.M. Michalik, D. Nadolski, A. Nagai, H. Nagar, N.M. Nakamura, M. Narayan, R. Narayanan, G. Natarajan, I. Nathanail, A. Neilsen, J. Neri, R. Ni, C. Noutsos, A. Nowak, M.A. Okino, H. Olivares, H. Ortiz-León, G.N. Oyama, T. zel, F. Palumbo, D.C.M. Park, J. Patel, N. Pen, U.-L. Pesce, D.W. Piétu, V. Plambeck, R. Popstefanija, A. Porth, O. Pötzl, F.M. Prather, B. Preciado-López, J.A. Psaltis, D. Pu, H.-Y. Ramakrishnan, V. Rao, R. Rawlings, M.G. Raymond, A.W. Rezzolla, L. Ricarte, A. Ripperda, B. Roelofs, F. Rogers, A. Ros, E. Rose, M. Roshanineshat, A. Rottmann, H. Roy, A.L. Ruszczyk, C. Rygl, K.L.J. Sánchez, S. Sánchez-Arguelles, D. Sasada, M. Savolainen, T. Schloerb, F.P. Schuster, K.-F. Shao, L. Shen, Z. Small, D. Sohn, B.W. Soohoo, J. Sun, H. Tazaki, F. Tetarenko, A.J. Tiede, P. Tilanus, R.P.J. Titus, M. Toma, K. Torne, P. Trent, T. Traianou, E. Trippe, S. Bemmel, I.V. Van Langevelde, H.J. Van Rossum, D.R. Wagner, J. Ward-Thompson, D. Wardle, J. Weintroub, J. Wex, N. Wharton, R. Wielgus, M. Wong, G.N. Wu, Q. Yoon, D. Young, A. Young, K. Younsi, Z. Yuan, F. Yuan, Y.-F. Zensus, J.A. Zhao, G.-Y. Zhao, S.-S.

Subjects
Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

Event Horizon Telescope (EHT) observations at 230 GHz have now imaged polarized emission around the supermassive black hole in M87 on event-horizon scales. This polarized synchrotron radiation probes the structure of magnetic fields and the plasma properties near the black hole. Here we compare the resolved polarization structure observed by the EHT, along with simultaneous unresolved observations with the Atacama Large Millimeter/submillimeter Array, to expectations from theoretical models. The low fractional linear polarization in the resolved image suggests that the polarization is scrambled on scales smaller than the EHT beam, which we attribute to Faraday rotation internal to the emission region. We estimate the average density n e ∼ 104-7 cm-3, magnetic field strength B ∼ 1-30 G, and electron temperature T e ∼ (1-12) 1010 K of the radiating plasma in a simple one-zone emission model. We show that the net azimuthal linear polarization pattern may result from organized, poloidal magnetic fields in the emission region. In a quantitative comparison with a large library of simulated polarimetric images from general relativistic magnetohydrodynamic (GRMHD) simulations, we identify a subset of physical models that can explain critical features of the polarimetric EHT observations while producing a relativistic jet of sufficient power. The consistent GRMHD models are all of magnetically arrested accretion disks, where near-horizon magnetic fields are dynamically important. We use the models to infer a mass accretion rate onto the black hole in M87 of (3-20) 10-4 M o˙ yr-1. © 2021. The Author(s). Published by the American Astronomical Society..

Published
2021

6. Broadband Multi-wavelength Properties of M87 during the 2017 Event Horizon Telescope Campaign

Author

Algaba, J.C. Anczarski, J. Asada, K. Baloković, M. Chandra, S. Cui, Y.-Z. Falcone, A.D. Giroletti, M. Goddi, C. Hada, K. Haggard, D. Jorstad, S. Kaur, A. Kawashima, T. Keating, G. Kim, J.-Y. Kino, M. Komossa, S. Kravchenko, E.V. Krichbaum, T.P. Lee, S.-S. Lu, R.-S. Lucchini, M. Markoff, S. Neilsen, J. Nowak, M.A. Park, J. Principe, G. Ramakrishnan, V. Reynolds, M.T. Sasada, M. Savchenko, S.S. Williamson, K.E. Akiyama, K. Alberdi, A. Alef, W. Anantua, R. Azulay, R. Baczko, A.-K. Ball, D. Barrett, J. Bintley, D. Benson, B.A. Blackburn, L. Blundell, R. Boland, W. Bouman, K.L. Bower, G.C. Boyce, H. Bremer, M. Brinkerink, C.D. Brissenden, R. Britzen, S. Broderick, A.E. Broguiere, D. Bronzwaer, T. Byun, D.-Y. Carlstrom, J.E. Chael, A. Chan, C.-K. Chatterjee, S. Chatterjee, K. Chen, M.-T. Chen, Y. Chesler, P.M. Cho, I. Christian, P. Conway, J.E. Cordes, J.M. Crawford, T.M. Crew, G.B. Cruz-Osorio, A. Davelaar, J. De Laurentis, M. Deane, R. Dempsey, J. Desvignes, G. Dexter, J. Doeleman, S.S. Eatough, R.P. Falcke, H. Farah, J. Fish, V.L. Fomalont, E. Ford, H.A. Fraga-Encinas, R. Friberg, P. Fromm, C.M. Fuentes, A. Galison, P. Gammie, C.F. García, R. Gentaz, O. Georgiev, B. Gold, R. Gómez, J.L. Gómez-Ruiz, A.I. Gu, M. Gurwell, M. Hecht, M.H. Hesper, R. Ho, L.C. Ho, P. Honma, M. Huang, C.-W.L. Huang, L. Hughes, D.H. Ikeda, S. Inoue, M. Issaoun, S. James, D.J. Jannuzi, B.T. Janssen, M. Jeter, B. Jiang, W. Jiménez-Rosales, A. Johnson, M.D. Jung, T. Karami, M. Karuppusamy, R. Kettenis, M. Kim, D.-J. Kim, J. Kim, J. Koay, J.Y. Kofuji, Y. Koch, P.M. Koyama, S. Kramer, M. Kramer, C. Kuo, C.-Y. Lauer, T.R. Levis, A. Li, Y.-R. Li, Z. Lindqvist, M. Lico, R. Lindahl, G. Liu, J. Liu, K. Liuzzo, E. Lo, W.-P. Lobanov, A.P. Loinard, L. Lonsdale, C. Macdonald, N.R. Mao, J. Marchili, N. Marrone, D.P. Marscher, A.P. Martí-Vidal, I. Matsushita, S. Matthews, L.D. Medeiros, L. Menten, K.M. Mizuno, I. Mizuno, Y. Moran, J.M. Moriyama, K. Moscibrodzka, M. Müller, C. Musoke, G. Mejías, A.M. Nagai, H. Nagar, N.M. Nakamura, M. Narayan, R. Narayanan, G. Natarajan, I. Nathanail, A. Neri, R. Ni, C. Noutsos, A. Okino, H. Olivares, H. Ortiz-León, G.N. Oyama, T. Ozel, F. Palumbo, D.C.M. Patel, N. Pen, U.-L. Pesce, D.W. Piétu, V. Plambeck, R. Popstefanija, A. Porth, O. Pötzl, F.M. Prather, B. Preciado-López, J.A. Psaltis, D. Pu, H.-Y. Rao, R. Rawlings, M.G. Raymond, A.W. Rezzolla, L. Ricarte, A. Ripperda, B. Roelofs, F. Rogers, A. Ros, E. Rose, M. Roshanineshat, A. Rottmann, H. Roy, A.L. Ruszczyk, C. Rygl, K.L.J. Sánchez, S. Sánchez-Arguelles, D. Savolainen, T. Schloerb, F.P. Schuster, K.-F. Shao, L. Shen, Z. Small, D. Sohn, B.W. Soohoo, J. Sun, H. Tazaki, F. Tetarenko, A.J. Tiede, P. Tilanus, R.P.J. Titus, M. Toma, K. Torne, P. Trent, T. Traianou, E. Trippe, S. Van Bemmel, I. Van Langevelde, H.J. Van Rossum, D.R. Wagner, J. Ward-Thompson, D. Wardle, J. Weintroub, J. Wex, N. Wharton, R. Wielgus, M. Wong, G.N. Wu, Q. Yoon, D. Young, A. Young, K. Younsi, Z. Yuan, F. Yuan, Y.-F. Zensus, J.A. Zhao, G.-Y. Zhao, S.-S. Principe, G. Giroletti, M. D'Ammando, F. Orienti, M. Abdalla, H. Adam, R. Aharonian, F. Benkhali, F.A. Angüner, E.O. Arcaro, C. Armand, C. Armstrong, T. Ashkar, H. Backes, M. Baghmanyan, V. Barbosa Martins, V. Barnacka, A. Barnard, M. Becherini, Y. Berge, D. Bernlöhr, K. Bi, B. Böttcher, M. Boisson, C. Bolmont, J. De Bony De Lavergne, M. Breuhaus, M. Brun, F. Brun, P. Bryan, M. Büchele, M. Bulik, T. Bylund, T. Caroff, S. Carosi, A. Casanova, S. Chand, T. Chen, A. Cotter, G. Curyło, M. Damascene Mbarubucyeye, J. Davids, I.D. Davies, J. Deil, C. Devin, J. Dewilt, P. Dirson, L. Djannati-Ataï, A. Dmytriiev, A. Donath, A. Doroshenko, V. Duffy, C. Dyks, J. Egberts, K. Eichhorn, F. Einecke, S. Emery, G. Ernenwein, J.-P. Feijen, K. Fegan, S. Fiasson, A. De Clairfontaine, G.F. Fontaine, G. Funk, S. Füßling, M. Gabici, S. Gallant, Y.A. Giavitto, G. Giunti, L. Glawion, D. Glicenstein, J.F. Gottschall, D. Grondin, M.-H. Hahn, J. Haupt, M. Hermann, G. Hinton, J.A. Hofmann, W. Hoischen, C. Holch, T.L. Holler, M. Hörbe, M. Horns, D. Huber, D. Jamrozy, M. Jankowsky, D. Jankowsky, F. Jardin-Blicq, A. Joshi, V. Jung-Richardt, I. Kasai, E. Kastendieck, M.A. Katarzyński, K. Katz, U. Khangulyan, D. Khélifi, B. Klepser, S. Kluźniak, W. Komin, N. Konno, R. Kosack, K. Kostunin, D. Kreter, M. Lamanna, G. Lemiere, A. Lemoine-Goumard, M. Lenain, J.-P. Levy, C. Lohse, T. Lypova, I. Mackey, J. Majumdar, J. Malyshev, D. Malyshev, D. Marandon, V. Marchegiani, P. Marcowith, A. Mares, A. Martí-Devesa, G. Marx, R. Maurin, G. Meintjes, P.J. Meyer, M. Moderski, R. Mohamed, M. Mohrmann, L. Montanari, A. Moore, C. Morris, P. Moulin, E. Muller, J. Murach, T. Nakashima, K. Nayerhoda, A. De Naurois, M. Ndiyavala, H. Niederwanger, F. Niemiec, J. Oakes, L. O'Brien, P. Odaka, H. Ohm, S. Olivera-Nieto, L. De Ona Wilhelmi, E. Ostrowski, M. Panter, M. Panny, S. Parsons, R.D. Peron, G. Peyaud, B. Piel, Q. Pita, S. Poireau, V. Noel, A.P. Prokhorov, D.A. Prokoph, H. Pühlhofer, G. Punch, M. Quirrenbach, A. Rauth, R. Reichherzer, P. Reimer, A. Reimer, O. Remy, Q. Renaud, M. Rieger, F. Rinchiuso, L. Romoli, C. Rowell, G. Rudak, B. Ruiz-Velasco, E. Sahakian, V. Sailer, S. Sanchez, D.A. Santangelo, A. Sasaki, M. Scalici, M. Schutte, H.M. Schwanke, U. Schwemmer, S. Seglar-Arroyo, M. Senniappan, M. Seyffert, A.S. Shafi, N. Shiningayamwe, K. Simoni, R. Sinha, A. Sol, H. Specovius, A. Spencer, S. Spir-Jacob, M. Stawarz, Ł. Sun, L. Steenkamp, R. Stegmann, C. Steinmassl, S. Steppa, C. Takahashi, T. Tavernier, T. Taylor, A.M. Terrier, R. Tiziani, D. Tluczykont, M. Tomankova, L. Trichard, C. Tsirou, M. Tuffs, R. Uchiyama, Y. Van Der Walt, D.J. Van Eldik, C. Van Rensburg, C. Van Soelen, B. Vasileiadis, G. Veh, J. Venter, C. Vincent, P. Vink, J. Völk, H.J. Vuillaume, T. Wadiasingh, Z. Wagner, S.J. Watson, J. Werner, F. White, R. Wierzcholska, A. Wong, Y.W. Yusafzai, A. Zacharias, M. Zanin, R. Zargaryan, D. Zdziarski, A.A. Zech, A. Zhu, S.J. Zorn, J. Zouari, S. Żywucka, N. Acciari, V.A. Ansoldi, S. Antonelli, L.A. Engels, A.A. Artero, M. Asano, K. Baack, D. Babić, A. Baquero, A. De Almeida, U.B. Barrio, J.A. Becerra González, J. Bednarek, W. Bellizzi, L. Bernardini, E. Bernardos, M. Berti, A. Besenrieder, J. Bhattacharyya, W. Bigongiari, C. Biland, A. Blanch, O. Bonnoli, G. Bošnjak, Ž. Busetto, G. Carosi, R. Ceribella, G. Cerruti, M. Chai, Y. Chilingarian, A. Cikota, S. Colak, S.M. Colombo, E. Contreras, J.L. Cortina, J. Covino, S. D'Amico, G. D'Elia, V. Da Vela, P. Dazzi, F. De Angelis, A. De Lotto, B. Delfino, M. Delgado, J. Delgado Mendez, C. Depaoli, D. Di Pierro, F. Di Venere, L. Do Souto Espineira, E. Dominis Prester, D. Donini, A. Dorner, D. Doro, M. Elsaesser, D. Fallah Ramazani, V. Fattorini, A. Ferrara, G. Fonseca, M.V. Font, L. Fruck, C. Fukami, S. García López, R.J. Garczarczyk, M. Gasparyan, S. Gaug, M. Giglietto, N. Giordano, F. Gliwny, P. Godinović, N. Green, J.G. Green, D. Hadasch, D. Hahn, A. Heckmann, L. Herrera, J. Hoang, J. Hrupec, D. Hütten, M. Inada, T. Inoue, S. Ishio, K. Iwamura, Y. Jiménez, I. Jormanainen, J. Jouvin, L. Kajiwara, Y. Karjalainen, M. Kerszberg, D. Kobayashi, Y. Kubo, H. Kushida, J. Lamastra, A. Lelas, D. Leone, F. Lindfors, E. Lombardi, S. Longo, F. López-Coto, R. López-Moya, M. López-Oramas, A. Loporchio, S. Machado De Oliveira Fraga, B. Maggio, C. Majumdar, P. Makariev, M. Mallamaci, M. Maneva, G. Manganaro, M. Mannheim, K. Maraschi, L. Mariotti, M. Martínez, M. Mazin, D. Menchiari, S. Mender, S. Mićanović, S. Miceli, D. Miener, T. Minev, M. Miranda, J.M. Mirzoyan, R. Molina, E. Moralejo, A. Morcuende, D. Moreno, V. Moretti, E. Neustroev, V. Nigro, C. Nilsson, K. Nishijima, K. Noda, K. Nozaki, S. Ohtani, Y. Oka, T. Otero-Santos, J. Paiano, S. Palatiello, M. Paneque, D. Paoletti, R. Paredes, J.M. Pavletić, L. Penil, P. Perennes, C. Persic, M. Moroni, P.G.P. Prandini, E. Priyadarshi, C. Puljak, I. Rhode, W. Ribó, M. Rico, J. Righi, C. Rugliancich, A. Saha, L. Sahakyan, N. Saito, T. Sakurai, S. Satalecka, K. Saturni, F.G. Schleicher, B. Schmidt, K. Schweizer, T. Sitarek, J. Šnidarić, I. Sobczynska, D. Spolon, A. Stamerra, A. Strom, D. Strzys, M. Suda, Y. Surić, T. Takahashi, M. Tavecchio, F. Temnikov, P. Terzić, T. Teshima, M. Tosti, L. Truzzi, S. Tutone, A. Ubach, S. Van Scherpenberg, J. Vanzo, G. Vazquez Acosta, M. Ventura, S. Verguilov, V. Vigorito, C.F. Vitale, V. Vovk, I. Will, M. Wunderlich, C. Zarić, D. Adams, C.B. Benbow, W. Brill, A. Capasso, M. Christiansen, J.L. Chromey, A.J. Daniel, M.K. Errando, M. Farrell, K.A. Feng, Q. Finley, J.P. Fortson, L. Furniss, A. Gent, A. Giuri, C. Hassan, T. Hervet, O. Holder, J. Hughes, G. Humensky, T.B. Jin, W. Kaaret, P. Kertzman, M. Kieda, D. Kumar, S. Lang, M.J. Lundy, M. Maier, G. Moriarty, P. Mukherjee, R. Nieto, D. Nievas-Rosillo, M. O'Brien, S. Ong, R.A. Otte, A.N. Patel, S. Pfrang, K. Pohl, M. Prado, R.R. Pueschel, E. Quinn, J. Ragan, K. Reynolds, P.T. Ribeiro, D. Richards, G.T. Roache, E. Rulten, C. Ryan, J.L. Santander, M. Sembroski, G.H. Shang, R. Weinstein, A. Williams, D.A. Williamson, T.J. Hirota, T. Cui, L. Niinuma, K. Ro, H. Sakai, N. Sawada-Satoh, S. Wajima, K. Wang, N. Liu, X. Yonekura, Y.

Subjects
Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Cosmology and Extragalactic Astrophysics
Abstract

In 2017, the Event Horizon Telescope (EHT) Collaboration succeeded in capturing the first direct image of the center of the M87 galaxy. The asymmetric ring morphology and size are consistent with theoretical expectations for a weakly accreting supermassive black hole of mass ∼6.5 × 109 M o˙. The EHTC also partnered with several international facilities in space and on the ground, to arrange an extensive, quasi-simultaneous multi-wavelength campaign. This Letter presents the results and analysis of this campaign, as well as the multi-wavelength data as a legacy data repository. We captured M87 in a historically low state, and the core flux dominates over HST-1 at high energies, making it possible to combine core flux constraints with the more spatially precise very long baseline interferometry data. We present the most complete simultaneous multi-wavelength spectrum of the active nucleus to date, and discuss the complexity and caveats of combining data from different spatial scales into one broadband spectrum. We apply two heuristic, isotropic leptonic single-zone models to provide insight into the basic source properties, but conclude that a structured jet is necessary to explain M87's spectrum. We can exclude that the simultaneous γ-ray emission is produced via inverse Compton emission in the same region producing the EHT mm-band emission, and further conclude that the γ-rays can only be produced in the inner jets (inward of HST-1) if there are strongly particle-dominated regions. Direct synchrotron emission from accelerated protons and secondaries cannot yet be excluded. © 2021. The Author(s). Published by the American Astronomical Society..

Published
2021

7. Measurements of the E-Mode Polarization and Temperature-E-Mode Correlation of the CMB from SPT-3G 2018 Data

Author

Dutcher, D., Balkenhol, L., Ade, P.A.R., Ahmed, Z., Anderes, E., Anderson, A.J., Archipley, M., Avva, J.S., Aylor, K., Barry, P.S., Thakur, R. Basu, Benabed, K., Bender, A.N., Benson, B.A., Bianchini, F., Bleem, L.E., Bouchet, F.R., Bryant, L., Byrum, K., Carlstrom, J.E., Carter, F.W., Cecil, T.W., Chang, C.L., Chaubal, P., Chen, G., Cho, H.-M., Chou, T.-L., Cliche, J.-F., Crawford, T.M., Cukierman, A., Daley, C., De Haan, T., Denison, E.V., Dibert, K., Ding, J., Dobbs, M.A., Everett, W., Feng, C., Ferguson, K.R., Foster, A., Fu, J., Galli, S., Gambrel, A.E., Gardner, R.W., Goeckner-Wald, N., Gualtieri, R., Guns, S., Gupta, N., Guyser, R., Halverson, N.W., Harke-Hosemann, A.H., Harrington, N.L., Henning, J.W., Hilton, G.C., Hivon, E., Holder, G.P., Holzapfel, W.L., Hood, J.C., Howe, D., Huang, N., Irwin, K.D., Jeong, O.B., Jonas, M., Jones, A., Khaire, T.S., Knox, L., Kofman, A.M., Korman, M., Kubik, D.L., Kuhlmann, S., Kuo, C.-L., Lee, A.T., Leitch, E.M., Lowitz, A.E., Lu, C., Meyer, S.S., Michalik, D., Millea, M., Montgomery, J., Nadolski, A., Natoli, T., Nguyen, H., Noble, G.I., Novosad, V., Omori, Y., Padin, S., Pan, Z., Paschos, P., Pearson, J., Posada, C.M., Prabhu, K., Quan, W., Raghunathan, S., Rahlin, A., Reichardt, C.L., Riebel, D., Riedel, B., Rouble, M., Ruhl, J.E., Sayre, J.T., Schiappucci, E., Shirokoff, E., Smecher, G., Sobrin, J.A., Stark, A.A., Stephen, J., Story, K.T., Suzuki, A., Thompson, K.L., Thorne, B., Tucker, C., Umilta, C., Vale, L.R., Vanderlinde, K., Vieira, J.D., Wang, G., Whitehorn, N., Wu, W.L.K., Yefremenko, V., Yoon, K.W., Young, M.R., Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and SPT-3G

Subjects
dimension: 6, satellite: Planck, Cosmology and Nongalactic Astrophysics (astro-ph.CO), pole, cosmic background radiation: spectrum, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, gravitation: lens, cosmological model: parameter space, correlation, cosmic background radiation: multipole, polarization: power spectrum, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

International audience; We present measurements of the E-mode (EE) polarization power spectrum and temperature-E-mode (TE) cross-power spectrum of the cosmic microwave background using data collected by SPT-3G, the latest instrument installed on the South Pole Telescope. This analysis uses observations of a 1500 deg2 region at 95, 150, and 220 GHz taken over a four-month period in 2018. We report binned values of the EE and TE power spectra over the angular multipole range 300≤ℓ<3000, using the multifrequency data to construct six semi-independent estimates of each power spectrum and their minimum-variance combination. These measurements improve upon the previous results of SPTpol across the multipole ranges 300≤ℓ≤1400 for EE and 300≤ℓ≤1700 for TE, resulting in constraints on cosmological parameters comparable to those from other current leading ground-based experiments. We find that the SPT-3G data set is well fit by a ΛCDM cosmological model with parameter constraints consistent with those from Planck and SPTpol data. From SPT-3G data alone, we find H0=68.8±1.5 km s−1 Mpc−1 and σ8=0.789±0.016, with a gravitational lensing amplitude consistent with the ΛCDM prediction (AL=0.98±0.12). We combine the SPT-3G and the Planck data sets and obtain joint constraints on the ΛCDM model. The volume of the 68% confidence region in six-dimensional ΛCDM parameter space is reduced by a factor of 1.5 compared to Planck-only constraints, with no significant shifts in central values. We note that the results presented here are obtained from data collected during just half of a typical observing season with only part of the focal plane operable, and that the active detector count has since nearly doubled for observations made with SPT-3G after 2018.

Published
2021
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8. Constraints on black-hole charges with the 2017 EHT observations of M87∗

Author

Kocherlakota, P. Rezzolla, L. Falcke, H. Fromm, C.M. Kramer, M. Mizuno, Y. Nathanail, A. Olivares, H. Younsi, Z. Akiyama, K. Alberdi, A. Alef, W. Algaba, J.C. Anantua, R. Asada, K. Azulay, R. Baczko, A.-K. Ball, D. Baloković, M. Barrett, J. Benson, B.A. Bintley, D. Blackburn, L. Blundell, R. Boland, W. Bouman, K.L. Bower, G.C. Boyce, H. Bremer, M. Brinkerink, C.D. Brissenden, R. Britzen, S. Broderick, A.E. Broguiere, D. Bronzwaer, T. Byun, D.-Y. Carlstrom, J.E. Chael, A. Chan, C.-K. Chatterjee, S. Chatterjee, K. Chen, M.-T. Chen, Y. Chesler, P.M. Cho, I. Christian, P. Conway, J.E. Cordes, J.M. Crawford, T.M. Crew, G.B. Cruz-Osorio, A. Cui, Y. Davelaar, J. De Laurentis, M. Deane, R. Dempsey, J. Desvignes, G. Doeleman, S.S. Eatough, R.P. Farah, J. Fish, V.L. Fomalont, E. Fraga-Encinas, R. Friberg, P. Ford, H.A. Fuentes, A. Galison, P. Gammie, C.F. García, R. Gentaz, O. Georgiev, B. Goddi, C. Gold, R. Gómez, J.L. Gómez-Ruiz, A.I. Gu, M. Gurwell, M. Hada, K. Haggard, D. Hecht, M.H. Hesper, R. Ho, L.C. Ho, P. Honma, M. Huang, C.-W.L. Huang, L. Hughes, D.H. Ikeda, S. Inoue, M. Issaoun, S. James, D.J. Jannuzi, B.T. Janssen, M. Jeter, B. Jiang, W. Jimenez-Rosales, A. Johnson, M.D. Jorstad, S. Jung, T. Karami, M. Karuppusamy, R. Kawashima, T. Keating, G.K. Kettenis, M. Kim, D.-J. Kim, J.-Y. Kim, J. Kim, J. Kino, M. Koay, J.Y. Kofuji, Y. Koch, P.M. Koyama, S. Kramer, C. Krichbaum, T.P. Kuo, C.-Y. Lauer, T.R. Lee, S.-S. Levis, A. Li, Y.-R. Li, Z. Lindqvist, M. Lico, R. Lindahl, G. Liu, J. Liu, K. Liuzzo, E. Lo, W.-P. Lobanov, A.P. Loinard, L. Lonsdale, C. Lu, R.-S. Macdonald, N.R. Mao, J. Marchili, N. Markoff, S. Marrone, D.P. Marscher, A.P. Martí-Vidal, I. Matsushita, S. Matthews, L.D. Medeiros, L. Menten, K.M. Mizuno, I. Moran, J.M. Moriyama, K. Moscibrodzka, M. Müller, C. Musoke, G. Mejías, A.M. Nagai, H. Nagar, N.M. Nakamura, M. Narayan, R. Narayanan, G. Natarajan, I. Neilsen, J. Neri, R. Ni, C. Noutsos, A. Nowak, M.A. Okino, H. Ortiz-León, G.N. Oyama, T. Özel, F. Palumbo, D.C.M. Park, J. Patel, N. Pen, U.-L. Pesce, D.W. Piétu, V. Plambeck, R. Popstefanija, A. Porth, O. Pötzl, F.M. Prather, B. Preciado-López, J.A. Psaltis, D. Pu, H.-Y. Ramakrishnan, V. Rao, R. Rawlings, M.G. Raymond, A.W. Ricarte, A. Ripperda, B. Roelofs, F. Rogers, A. Ros, E. Rose, M. Roshanineshat, A. Rottmann, H. Roy, A.L. Ruszczyk, C. Rygl, K.L.J. Sánchez, S. Sánchez-Arguelles, D. Sasada, M. Savolainen, T. Schloerb, F.P. Schuster, K.-F. Shao, L. Shen, Z. Small, D. Sohn, B.W. Soohoo, J. Sun, H. Tazaki, F. Tetarenko, A.J. Tiede, P. Tilanus, R.P.J. Titus, M. Toma, K. Torne, P. Trent, T. Traianou, E. Trippe, S. Van Bemmel, I. Van Langevelde, H.J. Van Rossum, D.R. Wagner, J. Ward-Thompson, D. Wardle, J. Weintroub, J. Wex, N. Wharton, R. Wielgus, M. Wong, G.N. Wu, Q. Yoon, D. Young, A. Young, K. Yuan, F. Yuan, Y.-F. Zensus, J.A. Zhao, G.-Y. Zhao, S.-S. (EHT Collaboration)

Subjects
General Relativity and Quantum Cosmology, Astrophysics::High Energy Astrophysical Phenomena
Abstract

Our understanding of strong gravity near supermassive compact objects has recently improved thanks to the measurements made by the Event Horizon Telescope (EHT). We use here the M87∗ shadow size to infer constraints on the physical charges of a large variety of nonrotating or rotating black holes. For example, we show that the quality of the measurements is already sufficient to rule out that M87∗ is a highly charged dilaton black hole. Similarly, when considering black holes with two physical and independent charges, we are able to exclude considerable regions of the space of parameters for the doubly-charged dilaton and the Sen black holes. © 2021 authors. Published by the American Physical Society.

Published
2021

9. Event Horizon Telescope observations of the jet launching and collimation in Centaurus A

Author

Janssen, M. Falcke, H. Kadler, M. Ros, E. Wielgus, M. Akiyama, K. Baloković, M. Blackburn, L. Bouman, K.L. Chael, A. Chan, C.-K. Chatterjee, K. Davelaar, J. Edwards, P.G. Fromm, C.M. Gómez, J.L. Goddi, C. Issaoun, S. Johnson, M.D. Kim, J. Koay, J.Y. Krichbaum, T.P. Liu, J. Liuzzo, E. Markoff, S. Markowitz, A. Marrone, D.P. Mizuno, Y. Müller, C. Ni, C. Pesce, D.W. Ramakrishnan, V. Roelofs, F. Rygl, K.L.J. van Bemmel, I. Alberdi, A. Alef, W. Algaba, J.C. Anantua, R. Asada, K. Azulay, R. Baczko, A.-K. Ball, D. Barrett, J. Benson, B.A. Bintley, D. Blundell, R. Boland, W. Bower, G.C. Boyce, H. Bremer, M. Brinkerink, C.D. Brissenden, R. Britzen, S. Broderick, A.E. Broguiere, D. Bronzwaer, T. Byun, D.-Y. Carlstrom, J.E. Chatterjee, S. Chen, M.-T. Chen, Y. Chesler, P.M. Cho, I. Christian, P. Conway, J.E. Cordes, J.M. Crawford, T.M. Crew, G.B. Cruz-Osorio, A. Cui, Y. De Laurentis, M. Deane, R. Dempsey, J. Desvignes, G. Dexter, J. Doeleman, S.S. Eatough, R.P. Farah, J. Fish, V.L. Fomalont, E. Ford, H.A. Fraga-Encinas, R. Friberg, P. Fuentes, A. Galison, P. Gammie, C.F. García, R. Gelles, Z. Gentaz, O. Georgiev, B. Gold, R. Gómez-Ruiz, A.I. Gu, M. Gurwell, M. Hada, K. Haggard, D. Hecht, M.H. Hesper, R. Himwich, E. Ho, L.C. Ho, P. Honma, M. Huang, C.-W.L. Huang, L. Hughes, D.H. Ikeda, S. Inoue, M. James, D.J. Jannuzi, B.T. Jeter, B. Jiang, W. Jimenez-Rosales, A. Jorstad, S. Jung, T. Karami, M. Karuppusamy, R. Kawashima, T. Keating, G.K. Kettenis, M. Kim, D.-J. Kim, J.-Y. Kim, J. Kino, M. Kofuji, Y. Koyama, S. Kramer, M. Kramer, C. Kuo, C.-Y. Lauer, T.R. Lee, S.-S. Levis, A. Li, Y.-R. Li, Z. Lindqvist, M. Lico, R. Lindahl, G. Liu, K. Lo, W.-P. Lobanov, A.P. Loinard, L. Lonsdale, C. Lu, R.-S. MacDonald, N.R. Mao, J. Marchili, N. Marscher, A.P. Martí-Vidal, I. Matsushita, S. Matthews, L.D. Medeiros, L. Menten, K.M. Mizuno, I. Moran, J.M. Moriyama, K. Moscibrodzka, M. Musoke, G. Mejías, A.M. Nagai, H. Nagar, N.M. Nakamura, M. Narayan, R. Narayanan, G. Natarajan, I. Nathanail, A. Neilsen, J. Neri, R. Noutsos, A. Nowak, M.A. Okino, H. Olivares, H. Ortiz-León, G.N. Oyama, T. Özel, F. Palumbo, D.C.M. Park, J. Patel, N. Pen, U.-L. Piétu, V. Plambeck, R. PopStefanija, A. Porth, O. Pötzl, F.M. Prather, B. Preciado-López, J.A. Psaltis, D. Pu, H.-Y. Rao, R. Rawlings, M.G. Raymond, A.W. Rezzolla, L. Ricarte, A. Ripperda, B. Rogers, A. Rose, M. Roshanineshat, A. Rottmann, H. Roy, A.L. Ruszczyk, C. Sánchez, S. Sánchez-Arguelles, D. Sasada, M. Savolainen, T. Schloerb, F.P. Schuster, K.-F. Shao, L. Shen, Z. Small, D. Sohn, B.W. SooHoo, J. Sun, H. Tazaki, F. Tetarenko, A.J. Tiede, P. Tilanus, R.P.J. Titus, M. Torne, P. Trent, T. Traianou, E. Trippe, S. van Bemmel, I. van Langevelde, H.J. van Rossum, D.R. Wagner, J. Ward-Thompson, D. Wardle, J. Weintroub, J. Wex, N. Wharton, R. Wong, G.N. Wu, Q. Yoon, D. Young, A. Young, K. Younsi, Z. Yuan, F. Yuan, Y.-F. Zensus, J.A. Zhao, G.-Y. Zhao, S.-S. The Event Horizon Telescope Collaboration

Abstract

Very-long-baseline interferometry (VLBI) observations of active galactic nuclei at millimetre wavelengths have the power to reveal the launching and initial collimation region of extragalactic radio jets, down to 10–100 gravitational radii (rg ≡ GM/c2) scales in nearby sources1. Centaurus A is the closest radio-loud source to Earth2. It bridges the gap in mass and accretion rate between the supermassive black holes (SMBHs) in Messier 87 and our Galactic Centre. A large southern declination of −43° has, however, prevented VLBI imaging of Centaurus A below a wavelength of 1 cm thus far. Here we show the millimetre VLBI image of the source, which we obtained with the Event Horizon Telescope at 228 GHz. Compared with previous observations3, we image the jet of Centaurus A at a tenfold higher frequency and sixteen times sharper resolution and thereby probe sub-lightday structures. We reveal a highly collimated, asymmetrically edge-brightened jet as well as the fainter counterjet. We find that the source structure of Centaurus A resembles the jet in Messier 87 on ~500 rg scales remarkably well. Furthermore, we identify the location of Centaurus A’s SMBH with respect to its resolved jet core at a wavelength of 1.3 mm and conclude that the source’s event horizon shadow4 should be visible at terahertz frequencies. This location further supports the universal scale invariance of black holes over a wide range of masses5,6. © 2021, The Author(s).

Published
2021

10. Polarimetric Properties of Event Horizon Telescope Targets from ALMA

Author

Goddi, C. Martí-Vidal, I. Messias, H. Bower, G.C. Broderick, A.E. Dexter, J. Marrone, D.P. Moscibrodzka, M. Nagai, H. Algaba, J.C. Asada, K. Crew, G.B. Gómez, J.L. Impellizzeri, C.M.V. Janssen, M. Kadler, M. Krichbaum, T.P. Lico, R. Matthews, L.D. Nathanail, A. Ricarte, A. Ros, E. Younsi, Z. Akiyama, K. Alberdi, A. Alef, W. Anantua, R. Azulay, R. Baczko, A.-K. Ball, D. Baloković, M. Barrett, J. Benson, B.A. Bintley, D. Blackburn, L. Blundell, R. Boland, W. Bouman, K.L. Boyce, H. Bremer, M. Brinkerink, C.D. Brissenden, R. Britzen, S. Broguiere, D. Bronzwaer, T. Byun, D.-Y. Carlstrom, J.E. Chael, A. Chan, C.-K. Chatterjee, S. Chatterjee, K. Chen, M.-T. Chen, Y. Chesler, P.M. Cho, I. Christian, P. Conway, J.E. Cordes, J.M. Crawford, T.M. Cruz-Osorio, A. Cui, Y. Davelaar, J. De Laurentis, M. Deane, R. Dempsey, J. Desvignes, G. Doeleman, S.S. Eatough, R.P. Falcke, H. Farah, J. Fish, V.L. Fomalont, E. Ford, H.A. Fraga-Encinas, R. Freeman, W.T. Friberg, P. Fromm, C.M. Fuentes, A. Galison, P. Gammie, C.F. Garciá, R. Gentaz, O. Georgiev, B. Gold, R. Gómez-Ruiz, A.I. Gu, M. Gurwell, M. Hada, K. Haggard, D. Hecht, M.H. Hesper, R. Ho, L.C. Ho, P. Honma, M. Huang, C.-W.L. Huang, L. Hughes, D.H. Inoue, M. Issaoun, S. James, D.J. Jannuzi, B.T. Jeter, B. Jiang, W. Jimenez-Rosales, A. Johnson, M.D. Jorstad, S. Jung, T. Karami, M. Karuppusamy, R. Kawashima, T. Keating, G.K. Kettenis, M. Kim, D.-J. Kim, J.-Y. Kim, J. Kim, J. Kino, M. Koay, J.Y. Kofuji, Y. Koch, P.M. Koyama, S. Kramer, M. Kramer, C. Kuo, C.-Y. Lauer, T.R. Lee, S.-S. Levis, A. Li, Y.-R. Li, Z. Lindqvist, M. Lindahl, G. Liu, J. Liu, K. Liuzzo, E. Lo, W.-P. Lobanov, A.P. Loinard, L. Lonsdale, C. Lu, R.-S. Macdonald, N.R. Mao, J. Marchili, N. Markoff, S. Marscher, A.P. Matsushita, S. Medeiros, L. Menten, K.M. Mizuno, I. Mizuno, Y. Moran, J.M. Moriyama, K. Müller, C. Musoke, G. Mejiás, A.M. Nagar, N.M. Nakamura, M. Narayan, R. Narayanan, G. Natarajan, I. Neilsen, J. Neri, R. Ni, C. Noutsos, A. Nowak, M.A. Okino, H. Olivares, H. Ortiz-León, G.N. Oyama, T. zel, F. Palumbo, D.C.M. Park, J. Patel, N. Pen, U.-L. Pesce, D.W. Piétu, V. Plambeck, R. Popstefanija, A. Porth, O. Pötzl, F.M. Prather, B. Preciado-López, J.A. Psaltis, D. Pu, H.-Y. Ramakrishnan, V. Rao, R. Rawlings, M.G. Raymond, A.W. Rezzolla, L. Ripperda, B. Roelofs, F. Rogers, A. Rose, M. Roshanineshat, A. Rottmann, H. Roy, A.L. Ruszczyk, C. Rygl, K.L.J. Sánchez, S. Sánchez-Arguelles, D. Sasada, M. Savolainen, T. Schloerb, F.P. Schuster, K.-F. Shao, L. Shen, Z. Small, D. Sohn, B.W. Soohoo, J. Sun, H. Tazaki, F. Tetarenko, A.J. Tiede, P. Tilanus, R.P.J. Titus, M. Toma, K. Torne, P. Trent, T. Traianou, E. Trippe, S. Bemmel, I.V. Van Langevelde, H.J. Van Rossum, D.R. Wagner, J. Ward-Thompson, D. Wardle, J. Weintroub, J. Wex, N. Wharton, R. Wielgus, M. Wong, G.N. Wu, Q. Yoon, D. Young, A. Young, K. Yuan, F. Yuan, Y.-F. Zensus, J.A. Zhao, G.-Y. Zhao, S.-S. Bruni, G. Gopakumar, A. Hernández-Gómez, A. Herrero-Illana, R. Ingram, A. Komossa, S. Kovalev, Y.Y. Muders, D. Perucho, M. Rösch, F. Valtonen, M.

Abstract

We present the results from a full polarization study carried out with the Atacama Large Millimeter/submillimeter Array (ALMA) during the first Very Long Baseline Interferometry (VLBI) campaign, which was conducted in 2017 April in the λ3 mm and λ1.3 mm bands, in concert with the Global mm-VLBI Array (GMVA) and the Event Horizon Telescope (EHT), respectively. We determine the polarization and Faraday properties of all VLBI targets, including Sgr A∗, M87, and a dozen radio-loud active galactic nuclei (AGNs), in the two bands at several epochs in a time window of 10 days. We detect high linear polarization fractions (2%-15%) and large rotation measures (RM > 103.3-105.5 rad m-2), confirming the trends of previous AGN studies at millimeter wavelengths. We find that blazars are more strongly polarized than other AGNs in the sample, while exhibiting (on average) order-of-magnitude lower RM values, consistent with the AGN viewing angle unification scheme. For Sgr A∗ we report a mean RM of (-4.2 0.3) 105 rad m-2 at 1.3 mm, consistent with measurements over the past decade and, for the first time, an RM of (-2.1 0.1) 105 rad m-2 at 3 mm, suggesting that about half of the Faraday rotation at 1.3 mm may occur between the 3 mm photosphere and the 1.3 mm source. We also report the first unambiguous measurement of RM toward the M87 nucleus at millimeter wavelengths, which undergoes significant changes in magnitude and sign reversals on a one year timescale, spanning the range from -1.2 to 0.3 105 rad m-2 at 3 mm and -4.1 to 1.5 105 rad m-2 at 1.3 mm. Given this time variability, we argue that, unlike the case of Sgr A∗, the RM in M87 does not provide an accurate estimate of the mass accretion rate onto the black hole. We put forward a two-component model, comprised of a variable compact region and a static extended region, that can simultaneously explain the polarimetric properties observed by both the EHT (on horizon scales) and ALMA (which observes the combined emission from both components). These measurements provide critical constraints for the calibration, analysis, and interpretation of simultaneously obtained VLBI data with the EHT and GMVA. © 2021. The American Astronomical Society.

Published
2021

11. South Pole Telescope optics

Author

Padin, S., Staniszewski, Z., Keisler, R., Joy, M., Stark, A.A., Ade, P.A.R., Aird, K.A., Benson, B.A., Bleem, L.E., Carlstrom, J.E., Chang, C.L., Crawford, T.M., Crites, A.T., Dobbs, M.A., Halverson, N.W., Heimsath, S., Hills, R.E., Holzapfel, W.L., Lawrie, C., Lee, A.T., Leitch, E.M., Leong, J., Lu, W., Lueker, M., McMahon, J.J., Meyer, S.S., Mohr, J.J., Montroy, T.E., Plagge, T., Pryke, C., Ruhl, J.E., Schaffer, K.K., Shirokoff, E., Spieler, H.G., and Vieira, J.D.

Subjects
Optics -- Research, Telescope -- Properties, Telescope -- Design and construction, Astronomy, Physics, South Pole Telescope (Telescope) -- Properties, South Pole Telescope (Telescope) -- Design and construction
Abstract

The South Pole Telescope is a 10 m diameter, wide-field, offset Gregorian telescope with a 966-pixel, millimeter-wave, bolometer array receiver. The telescope has an unusual optical system with a cold stop around the secondary. The design emphasizes low scattering and low background loading. All the optical components except the primary are cold, and the entire beam from prime focus to the detectors is surrounded by cold absorber. OCIS codes: 350.1260, 110.6770, 220.4880, 090.2910.

Published
2008

12. Optical performance of frequency-selective bolometers

Author

Perera, T.A., Downes, T.P., Meyer, S.S., Crawford, T.M., Cheng, E.S., Chen, T.C., Cottingham, D.A., Sharp, E.H., Silverberg, R.F., Finkbeiner, F.M., Fixsen, D.J., Logan, D.W., and Wilson, G.W.

Subjects
Bolometers -- Optical properties, Bolometers -- Spectra, Absorption spectra -- Research, Astronomy, Physics
Abstract

Frequency-selective bolometers (FSBs) are a new type of detector for millimeter and submillimeter wavelengths that are transparent to all but a narrow range of frequencies as set by characteristics of the absorber itself. Therefore stacks of FSBs tuned to different frequencies provide a low-loss compact method for utilizing a large fraction of the light collected by a telescope. Tests of prototype FSBs indicate that the absorption spectra are well predicted by models, that peak absolute absorption efficiencies of the order of 50% are attainable, and that their out-of-band transmission is high. OCIS codes: 120.5240, 260.3090, 260.5740, 350.2450.

Published
2006

13. Inflation Physics from the Cosmic Microwave Background and Large Scale Structure

Author

Abazajian, K.N, Arnold,K, Austermann, J, Benson, B.A, Bischoff, C, Bock, J, Bond, J.R, Borrill, J, Buder, I, Burke, D.L, Calabrese, E, Carlstrom, J.E, Carvalho, C.S, Chang, C.L, Chiang, H.C, Church, S, Cooray, A, Crawford, T.M, Crill, B.P, Dawson, K.S, Das, S, Devline, M.J, Dobbs, M, Dodelson, S, and Wollack, E. J

Subjects
Astrophysics
Abstract

Fluctuations in the intensity and polarization of the cosmic microwave background (CMB) and the large-scale distribution of matter in the universe each contain clues about the nature of the earliest moments of time. The next generation of CMB and large-scale structure (LSS) experiments are poised to test the leading paradigm for these earliest moments---the theory of cosmic inflation---and to detect the imprints of the inflationary epoch, thereby dramatically increasing our understanding of fundamental physics and the early universe. A future CMB experiment with sufficient angular resolution and frequency coverage that surveys at least 1 of the sky to a depth of 1 uK-arcmin can deliver a constraint on the tensor-to-scalar ratio that will either result in a 5-sigma measurement of the energy scale of inflation or rule out all large-field inflation models, even in the presence of foregrounds and the gravitational lensing B-mode signal. LSS experiments, particularly spectroscopic surveys such as the Dark Energy Spectroscopic Instrument, will complement the CMB effort by improving current constraints on running of the spectral index by up to a factor of four, improving constraints on curvature by a factor of ten, and providing non-Gaussianity constraints that are competitive with the current CMB bounds.

Published
2013

14. A perpendicular write head design for high-density recording

Author

Batra, Sharat, Covington, M., Crawford, T.M., Crue, Bill, van der Heijden, P.A.A., Jayashankar, J., Johns, Earl C., Kryder, Mark, Minor, Kevin, Rottmayer, Robert, Tran, Ut, and West, Jeffery

Subjects
Magnetic recorders and recording -- Analysis, Magnetism -- Research, Business, Electronics, Electronics and electrical industries
Abstract

In this paper, we discuss a single-pole perpendicular head design and process that is suitable for densities of the order of 100 Gb/[in.sup.2]. The single-pole write head was integrated with a narrow-track bottom spin valve reader. The design uses a single-turn coil to generate magnetomotive force in the head. Because of the very short yoke length that is achieved by using a single-coil turn, this writer design has a very low head inductance. Low magnetic impedance of the head makes it suitable for high data rate writing. Using the finite element model (FEM), the head geometry was optimized to write on media with coercivity ([H.sub.c]) of 5000 Oe. Because of the very efficient head structure, a write current below 100 mA was sufficient. As trackwidths are reduced, the field contours at the media show significant curvature, resulting in written-in transition curvature. Because of the very small yoke structure, no degradation of low-frequency amplitude up to [+ or -] 90 Oe of external field is observed. Index Terms--FEM, longitudinal recording, low inductance, micromagnetic model, perpendicular recording, single turn, SNR, stray field, thermal stability, transition curvature.

Published
2002

15. Methods for determination of response times of magnetic head materials

Author

Silva, T.J. and Crawford, T.M.

Subjects
Magnetic recorders and recording -- Heads, Waveguides -- Research, Thin films -- Magnetic properties, Business, Electronics, Electronics and electrical industries
Abstract

Measurements of magnetization response times in thin-film Permalloy are made by both electrical and optical methods. The electrical method measures the inductive voltage generated in a waveguide by the changing magnetization. The optical technique uses standard pump-probe sampling methods combined with the second-harmonic magneto-optic Kerr effect to directly measure magnetization angle as a function of time. Results of these measurements for a 75 nm thick Permalloy film are in good qualitative agreement. Index Terms - Coplanar waveguide, inductive voltage, Landau-Lifshitz damping, magnetic switching speed, magneto-optic sampling, second-harmonic magneto-optic Kerr effect.

Published
1999

17. Dark Energy Survey Year 1 Results: Cross-correlation between Dark Energy Survey Y1 galaxy weak lensing and South Pole Telescope +Planck CMB weak lensing

Author

Omori, Y., Baxter, E.J., Kirk, D., Alarcon, A., Bernstein, G.M., Bleem, L.E., Cawthon, R., Choi, A., Chown, R., Crawford, T.M., Davis, C., De Vicente, J., DeRose, J., Dodelson, S., Eifler, T.F., Fosalba, P., Friedrich, O., Gatti, M., Gaztanaga, E., Giannantonio, T., Gruen, D., Hartley, W.G., Holder, G.P., Hoyle, B., Huterer, D., Jain, B., Jarvis, M., Krause, E., MacCrann, N., Miquel, R., Prat, J., Rau, M.M., Reichardt, C.L., ROZO, E., Samuroff, S., Sánchez, C., Secco, L.F., Sheldon, E., Simard, G., Troxel, M.A., Vielzeuf, P., Wechsler, R.H., Zuntz, J., Abbott, T.M.C., Abdalla, F.B., Allam, S., Annis, J., Avila, S., Aylor, K., Benson, B.A., Bertin, E., Bridle, S.L., Brooks, D., Burke, D.L., Carlstrom, J.E., Carnero Rosell, A., Carrasco Kind, M., Carretero, J., Castander, F.J., Chang, C.L., Cho, H-M., Crites, A.T., Crocce, M., Cunha, C.E., Da Costa, L.N., De Haan, T., Desai, S., Diehl, H.T., Dietrich, J.P., Dobbs, M.A., Everett, W.B., Fernandez, E., Flaugher, B., Frieman, J., García-Bellido, J., George, E.M., Gruendl, R.A., Gutierrez, G., Halverson, N.W., Harrington, N.L., Hollowood, D.L., Honscheid, K., Holzapfel, W.L., Hou, Z., Hrubes, J.D., James, D.J., Jeltema, T., Kuehn, K., Kuropatkin, N., Lima, M., Lin, H., Lee, A.T., Leitch, E.M., Luong-Van, D., Maia, M.A.G., Manzotti, A., Marrone, D.P., Marshall, J.L., Martini, P., McMahon, J.J., Melchior, P., Menanteau, F., Meyer, S.S., Mocanu, L.M., Mohr, J.J., Natoli, T., Ogando, R.L.C., Padin, S., Plazas, A.A., Pryke, C., Romer, A.K., Roodman, A., Ruhl, J.E., Rykoff, E.S., Sanchez, E., Scarpine, V., Schaffer, K.K., Schindler, R., Sevilla-Noarbe, I., Shirokoff, E., Smith, M., Smith, R.C., Soares-Santos, M., Sobreira, F., Staniszewski, Z., Stark, A.A., Story, K.T., Suchyta, E., Swanson, M.E.C., Tarle, G., Thomas, D., Vanderlinde, K., Vieira, J.D., Vikram, V., Walker, A.R., Weller, J., Williamson, R., Wu, W.L.K., Zahn, O., Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), DES, and SPT

Subjects
Astrophysics::Cosmology and Extragalactic Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Cosmology
Abstract

International audience; We cross-correlate galaxy weak lensing measurements from the Dark Energy Survey (DES) year-one data with a cosmic microwave background (CMB) weak lensing map derived from South Pole Telescope (SPT) and Planck data, with an effective overlapping area of 1289 deg2. With the combined measurements from four source galaxy redshift bins, we obtain a detection significance of 5.8σ. We fit the amplitude of the correlation functions while fixing the cosmological parameters to a fiducial ΛCDM model, finding A=0.99±0.17. We additionally use the correlation function measurements to constrain shear calibration bias, obtaining constraints that are consistent with previous DES analyses. Finally, when performing a cosmological analysis under the ΛCDM model, we obtain the marginalized constraints of Ωm=0.261-0.051+0.070 and S8≡σ8Ωm/0.3=0.660-0.100+0.085. These measurements are used in a companion work that presents cosmological constraints from the joint analysis of two-point functions among galaxies, galaxy shears, and CMB lensing using DES, SPT, and Planck data.

Published
2019

19. Fast magnetization switching with circularly polarized fields and short pulses

Author

Scholz, Werner, Crawford, T.M., Parker, Gregory J., Clinton, T.W., Ambrose, T., Kaka, Shehzaad, and Batra, Sharat

Subjects
Landau damping -- Analysis, Magnetization -- Analysis, Switching circuits -- Analysis, Business, Electronics, Electronics and electrical industries
Abstract

In this paper, we study the magnetization reversal process of single-domain Stoner--Wohlfarth particles subject to circularly polarized fields and short pulses using analytical and numerical models. We investigate the effect of short unipolar, bipolar field, and circularly polarized field pulses, which are applied perpendicular to the uniaxial magnetocrystalline anisotropy axis, on the magnetization switching dynamics. Index Terms--Fast switching, Landau--Lifshitz--Gilbert (LLG) equation, magnetization reversal.

Published
2008

20. Consistency of cosmic microwave background temperature measurements in three frequency bands in the 2500-square-degree SPT-SZ survey

Author

Mocanu, L.M., primary, Crawford, T.M., additional, Aylor, K., additional, Benson, B.A., additional, Bleem, L.E., additional, Carlstrom, J.E., additional, Chang, C.L., additional, Cho, H.-M., additional, Chown, R., additional, Crites, A.T., additional, de Haan, T., additional, Dobbs, M.A., additional, Everett, W.B., additional, George, E.M., additional, Halverson, N.W., additional, Harrington, N.L., additional, Henning, J.W., additional, Holder, G.P., additional, Holzapfel, W.L., additional, Hou, Z., additional, Hrubes, J.D., additional, Knox, L., additional, Lee, A.T., additional, Luong-Van, D., additional, Marrone, D.P., additional, McMahon, J.J., additional, Meyer, S.S., additional, Millea, M., additional, Mohr, J.J., additional, Natoli, T., additional, Omori, Y., additional, Padin, S., additional, Pryke, C., additional, Reichardt, C.L., additional, Ruhl, J.E., additional, Sayre, J.T., additional, Schaffer, K.K., additional, Shirokoff, E., additional, Staniszewski, Z., additional, Stark, A.A., additional, Story, K.T., additional, Vanderlinde, K., additional, Vieira, J.D., additional, Williamson, R., additional, and Wu, W.L.K., additional

Published
2019
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21. Stress dependence of soft, high moment and nanocrystalline FeCoB films

Author

Minor, M. Kevin, Crawford, T.M., Klemmer, Timothy J., Yingguo Peng, and Laughlin, David E.

Subjects
Magnetization -- Analysis, Cobalt -- Magnetic properties, Iron compounds -- Magnetic properties, Dielectric films -- Magnetic properties, Thin films -- Magnetic properties, Physics
Abstract

Nanocrystalline FeCoB exhibiting a saturation magnetization of ~ 2.2T is examined. The film stress increases from compressive to tensile with a critical pressure of ~ 12 mTorr with the increase in pressure.

Published
2002

22. High frequency dynamics of the soft underlayer in perpendicular recording system

Author

G. Ju, Veerdonk, R.J.M. van de, Tamaru, S., Crawford, T.M., Parker, G., Kubota, Y., M.L. Wu, Batra, S., Weller, D., and Bain, J.A.

Subjects
Iron compounds -- Magnetic properties, Magnetization -- Analysis, Storage media -- Research, Physics
Abstract

The time-resolved Kerr microscopy data of the magnetization dynamics in a 20-nm-thick FeCoB soft magnetic underlayer (SUL) film in response to reversal field pulses with 0.8 ns rise time is discussed. SUL films exhibited precessional effects with frequencies in the 3-7 GHz range.

Published
2002

23. Imaging of quantized magnetostatic modes using spatially resolved ferromagnetic resonance

Author

Tamaru, S., Bain, J.A., Veerdonk, R.J.M. van de, Crawford, T.M., Covington, M., and Kryder, M.H.

Subjects
Physics -- Research, Ferromagnetism -- Analysis, Magnetic resonance -- Analysis, Magnetostatics -- Analysis, Physics
Abstract

The performance of spatially resolved ferromagnetic resonance (FMR) with a proposed measurement technique is discussed. The decline in the number of nodes due to an increase in the bias field and the appearance of quantized magnetostatic mode waves at certain bias fields is observed.

Published
2002

24. Study of NiFe/Al/Al2O3 magnetic tunnel junction interfaces using second-harmonic magneto-optic Kerr effect

Author

Russek, S.E., Crawford, T.M., and Silva, T.J.

Subjects
Magnetism -- Research, Thin films -- Magnetic properties, Magneto-optics -- Analysis, Semiconductors -- Junctions, Physics
Abstract

A study was conducted to analyze the interfacial magnetic characteristics of NiFe/Al/Al2O3 heterostructures as a function of Al2O3 thickness and processing conditions. The thin films were prepared by sputter deposition onto oxidized silicon substrates. The second-harmonic magneto-optic Kerr effect was utilized to carry out the analysis. Experimental results indicated the effectiveness of the Kerr effect in evaluating tunnel junction quality during processing.

Published
1999

25. Determination of the magnetic damping constant in NiFe films

Author

Sandler, G.M., Bertram, H.N., Silva, T.J., and Crawford, T.M.

Subjects
Magnetism -- Research, Damping (Mechanics) -- Research, Thin films -- Research, Physics
Abstract

A study was conducted to analyze a two-dimensional, dynamic, micromagnetic framework of a thin strip of permalloy. The model was utilized to examine the magnetization dynamics of the strip as it is subjected to a transverse step field. The damping was matched by varying the phenomenological damping parameter in the LLG equation. In addition, the strip was assumed to be infinitely long and thin that it is sufficient to discretize only across the transverse direction.

Published
1999

26. Second-harmonic magneto-optic Kerr effect from spin-valve test structures: correlation with magnetoresistance response

Author

Crawford, T.M., Rogers, C.T., Silva, T.J., and Kim, Y.K.

Subjects
Harmonics (Electric waves) -- Research, Magneto-optics -- Research, Thin films -- Magnetic properties, Business, Electronics, Electronics and electrical industries
Abstract

We have simultaneously measured the second-harmonic magneto-optic Kerr effect and the magnetoresistance of patterned Ta/[Ni.sub.81][Fe.sub.19]/Cu/[Ni.sub.81][Fe.sub.19]/Ta spin-valve test structures. For fields applied parallel to the bias-current direction, we observed a one-to-one correlation between the magnetoresistance and the magnetization-dependent second-harmonic intensity. The dependence of the second-harmonic intensity on magnetic field indicates that the detected second-harmonic response arises largely from the top [Ni.sub.81][Fe.sub.19]/Ta interface. The existence of this one-to-one correlation implies that the second harmonic depends linearly on magnetization, thus offering a method for interfacespecific magnetometry.

Published
1997

27. Transverse and longitudinal second-harmonic magneto-optic Kerr effect observed from Ni81Fe19 thin film structures

Author

Crawford, T.M., Rogers, C.T., Silva, T.J., and Kim, Y.K.

Subjects
Thin films -- Optical properties, Magnetic media -- Evaluation, Polarization (Light) -- Measurement, Business, Electronics, Electronics and electrical industries
Abstract

We report measurements of the second-harmonic magneto-optic Kerr effect in both transverse and longitudinal geometries from 100-nm-thick [Ni.sub.81][Fe.sub.19] films. For the transverse geometry, we observe intensity changes of roughly a factor of 3 upon magnetization reversal. In the longitudinal geometry, the second harmonic Kerr angle is 32.6 [degrees] for s-incidence and 6.8 [degrees] for p-incidence. A simple theoretical treatment allows us to compare the relevant second-order susceptibility elements as measured in the two geometries: the element magnitudes and relative phase shifts agree within experimental error.

Published
1996

28. Alkanethiol induced changes in the magnetotransport properties of Co/Au bilayers

Author

Knaus, B., Garzon, S., and Crawford, T.M.

Subjects
Cobalt alloys -- Electric properties, Cobalt alloys -- Magnetic properties, Gold -- Magnetic properties, Gold -- Electric properties, Hall effect -- Analysis, Magnetostatics -- Analysis, Thiols -- Magnetic properties, Thiols -- Electric properties, Physics
Abstract

The chemisorption of a dodecanethiol ([C.sub.12][H.sub.25]SH) self-assembled monolayer on the surface of a Au film has altered the coercivity [H.sub.c] of an underlying Co film, which is measured by using the Planar Hall effect. The studies have shown that the coercivity shifts are caused by magnetostatic fields originating at the Au-thiol interface, which has affected the Co domain structure during magnetization reversal.

Published
2009

30. Recording head metrology at sub-100 nm device dimensions

Author

Gokemeijer, N.J., Clinton, T.W., Crawford, T.M., and Johnson, Mark

Subjects
Magnetic recorders and recording -- Observations, Arsenic compounds -- Properties, Magnetic fields -- Measurement, Indium -- Properties, Physics
Abstract

A study is carried out on a patterned InAs Hall cross that was used to quantitatively image the magnetic field produced by magnetic recording write head as a function of current. The results demonstrate that the potential of near-contact recording metrology for magnetic recording heads targeting 1 Tbit/in(super 2) areal-density information storage.

Published
2005

31. The TopHat experiment: A balloon-borne instrument for mapping millimeter and submillimeter emission

Author

Silverberg, R.F., Cheng, E.S., Aguirre, J.E., Bezaire, J.J., Crawford, T.M., Meyer, S.S., Bier, A., Campano, B., Chen, T.C., Cottingham, D.A., Sharp, E.H., Christensen, P.R., Cordone, S., Timbie, P.T., Dame, R.E., Fixsen, D.J., Kristensen, R.J.K., Nørgaard-Nielsen, Hans Ulrik, and Wilson, G.W.

Subjects
cosmic microwave background, Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Galaxy Astrophysics, observations [cosmology], general [galaxies], balloons
Abstract

The TopHat experiment was designed to measure the anisotropy in the cosmic microwave background radiation on angular scales from 0.degrees 3 to 30 degrees and the thermal emission from both Galactic and extragalactic dust. The balloon-borne instrument had five spectral bands spanning frequencies from 175 to 630 GHz. The telescope was a compact, 1 m, on-axis Cassegrain telescope designed to scan the sky at a fixed elevation of 78 degrees. The radiometer used cryogenic bolometers coupled to a single feed horn via a dichroic filter system. The observing strategy was intended to efficiently cover a region 48 degrees in diameter centered on the south polar cap with a highly cross-linked and redundant pattern with nearly uniform sky coverage. The Long Duration Balloon flight over Antarctica in 2001 January surveyed about 6% of the sky. Here we describe the design of the instrument and the achieved in-flight performance and provide a brief discussion of the data analysis.

Published
2005

32. The spectrum of integrated millimeter flux of the Magellanic Clouds and 30 Doradus from Tophat and Dirbe data

Author

Aguirre, J.E., Bezaire, J.J., Cheng, E.S., Cottingham, D.A., Cordone, S.S., Crawford, T.M., Fixsen, D.J., Knox, L., Meyer, S.S., Nørgaard-Nielsen, Hans Ulrik, Silverberg, R.F., Timbie, P., Wilson, G.W., Aguirre, J.E., Bezaire, J.J., Cheng, E.S., Cottingham, D.A., Cordone, S.S., Crawford, T.M., Fixsen, D.J., Knox, L., Meyer, S.S., Nørgaard-Nielsen, Hans Ulrik, Silverberg, R.F., Timbie, P., and Wilson, G.W.

Abstract

We present measurements of the integrated flux relative to the local background of the Large and Small Magellanic Clouds and the region 30 Doradus (the Tarantula Nebula) in the LMC in four frequency bands centered at 245, 400, 460, and 630 GHz, based on observations made with the TopHat telescope. We combine these observations with the corresponding measurements for the DIRBE bands 8, 9, and 10 to cover the frequency range 245-3000 GHz (100-1220 mum) for these objects. We present spectra for all three objects and fit these spectra to a single-component graybody emission model and report best-fit dust temperatures, optical depths, and emissivity power-law indices, and we compare these results with other measurements in these regions and elsewhere. Using published dust grain opacities, we estimate the mass of the measured dust component in the three regions.

Published
2003

34. Inductive measurement of ultrafast magnetization dynamics in thin-film Permalloy

Author

Silva, T.J., Lee, C.S., Crawford, T.M., and Rogers, C.T.

Subjects
Ferrite devices -- Research, Magnetic devices -- Research, Magnetic alloys -- Research, Magnetic materials -- Research, Thin films -- Research, Disk drives -- Research, Computer storage devices -- Research, Physics
Abstract

A study magnetic components in hard disk drive data-storage systems describes an inductive technique for calculating the ultra-high-speed magnetic phenomena in thin film materials. The experiment also reports response times for Ni81Fe19, or Permalloy, which is a magnetic alloy used throughout the data storage industry for recording heads. Experimental materials, methodology, findings and conclusions are presented.

Published
1999

35. Thermal asperity trends

Author

Stupp, S.E., primary, Baldwinson, M.A., additional, McEwen, P., additional, Crawford, T.M., additional, and Rogers, C.T., additional

Published
1999
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43. Writing and reading bits on pre-patterned media.

Author

Moritz, J., Buda, L., Dieny, B., Nozières, J.P., van de Veerdonk, R.J.M., Crawford, T.M., and Weller, D.

Subjects
ELECTRON beam lithography, MAGNETIC devices, MICROELECTRONICS, LITHOGRAPHY, ELECTRON beams, PRINTING
Abstract

We have written and read back bits on perpendicular pre-patterned media prepared by electron-beam lithography. Using a contact tester equipped with a standard longitudinal head, we are able to write different bit lengths on 100×200 nm[sup 2] dots spaced 100 nm apart. These tests demonstrate the role played by the distribution of the coercive fields of the dots during the write process. Signal-to-noise ratios (SNRs) are obtained by numerical analysis and are found to be on the same order of magnitude as in continuous perpendicular media, but remain constant at decreasing bit lengths. This property of the SNR is due to a partial reduction of transition noise. The potential to pattern these media with nanoimprint lithography and their good recording performance make them candidates for ultrahigh density recording. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Published
2004
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44. Minestrone.

Author

Crawford, T.M.

Subjects
SHORT story (Literary form)
Abstract

Presents the short story 'Minestrone,' by T.M. Crawford.

Published
1997

46. Observation of the transverse second-harmonic magneto-optic Kerr effect from....

Author

Crawford, T.M. and Rogers, C.T.

Subjects
*SECOND harmonic generation, *THIN films
Abstract

Observes second-harmonic magneto-optic Kerr measurements on air-exposed, polycrystalline Ni[sub 81]Fe[sub 19] thin films. Change in second-harmonic intensity upon magnetization reversal; Interference between second-harmonic fields from various interfaces; Deterioration of ferromagnetism in the 1 and 2 nanometer films.

Published
1996
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47. Year two instrument status of the SPT-3G cosmic microwave background receiver

Author

Zmuidzinas, Jonas, Gao, Jian-Rong, Bender, A.N., Ade, P.A.R, Ahmed, Z., Anderson, A.J., Avva, J.S., Aylor, K., Barry, P.S., Basu Thakur, R., Benson, B.A., Bleem, L.S., Bocquet, S., Byrum, K., Carlstrom, J.E., Carter, F.W., Cecil, T.W., Chang, C.L., Cho, H-M., Cliche, J.F., Crawford, T.M., Cukierman, A., de Haan, T., Denison, E.V., Ding, J., Dobbs, M.A., Dodelson, S., Dutcher, D., Everett, W., Foster, A., Gallicchio, J., Gilbert, A., Groh, J.C., Guns, S.T., Halverson, N.W., Harke-Hosemann, A.H., Harrington, N.L., Henning, J.W., Hilton, G.C., Holder, G.P., Holzapfel, W.L., Huang, N., Irwin, K.D., Jeong, O.B., Jonas, M., Jones, A., Khaire, T.S., Knox, L., Kofman, A.M., Korman, M., Kubik, D.L., Kuhlmann, S., Kuo, C-L., Lee, A.T., Leitch, E.M., Lowitz, A.E., Meyer, S.S., Michalik, D., Montgomery, J., Nadolski, A., Natoli, T., Nguyen, H., Noble, G.I., Novosad, V., Padin, S., Pan, Z., Pearson, J., Posada, C.M., Quan, W., Raghunathan, S., Rahlin, A., Reichardt, C.L., Ruhl, J.E., Sayre, J.T., Shirokoff, E., Smecher, G., Sobrin, J.A., Stark, A.A., Story, K.T., Suzuki, A., Thompson, K.L., Tucker, C., Vale, L.R., Vanderlinde, K., Vieira, J.D., Wang, G., Whitehorn, N., Wu, W.L.K., Yefremenko, V., Yoon, K.W., Zmuidzinas, Jonas, Gao, Jian-Rong, Bender, A.N., Ade, P.A.R, Ahmed, Z., Anderson, A.J., Avva, J.S., Aylor, K., Barry, P.S., Basu Thakur, R., Benson, B.A., Bleem, L.S., Bocquet, S., Byrum, K., Carlstrom, J.E., Carter, F.W., Cecil, T.W., Chang, C.L., Cho, H-M., Cliche, J.F., Crawford, T.M., Cukierman, A., de Haan, T., Denison, E.V., Ding, J., Dobbs, M.A., Dodelson, S., Dutcher, D., Everett, W., Foster, A., Gallicchio, J., Gilbert, A., Groh, J.C., Guns, S.T., Halverson, N.W., Harke-Hosemann, A.H., Harrington, N.L., Henning, J.W., Hilton, G.C., Holder, G.P., Holzapfel, W.L., Huang, N., Irwin, K.D., Jeong, O.B., Jonas, M., Jones, A., Khaire, T.S., Knox, L., Kofman, A.M., Korman, M., Kubik, D.L., Kuhlmann, S., Kuo, C-L., Lee, A.T., Leitch, E.M., Lowitz, A.E., Meyer, S.S., Michalik, D., Montgomery, J., Nadolski, A., Natoli, T., Nguyen, H., Noble, G.I., Novosad, V., Padin, S., Pan, Z., Pearson, J., Posada, C.M., Quan, W., Raghunathan, S., Rahlin, A., Reichardt, C.L., Ruhl, J.E., Sayre, J.T., Shirokoff, E., Smecher, G., Sobrin, J.A., Stark, A.A., Story, K.T., Suzuki, A., Thompson, K.L., Tucker, C., Vale, L.R., Vanderlinde, K., Vieira, J.D., Wang, G., Whitehorn, N., Wu, W.L.K., Yefremenko, V., and Yoon, K.W.

Abstract

The South Pole Telescope (SPT) is a millimeter-wavelength telescope designed for high-precision measurements of the cosmic microwave background (CMB). The SPT measures both the temperature and polarization of the CMB with a large aperture, resulting in high resolution maps sensitive to signals across a wide range of angular scales on the sky. With these data, the SPT has the potential to make a broad range of cosmological measurements. These include constraining the effect of massive neutrinos on large-scale structure formation as well as cleaning galactic and cosmological foregrounds from CMB polarization data in future searches for inflationary gravitational waves. The SPT began observing in January 2017 with a new receiver (SPT-3G) containing ~16,000 polarization-sensitive transition-edge sensor bolometers. Several key technology developments have enabled this large-format focal plane, including advances in detectors, readout electronics, and large millimeter-wavelength optics. We discuss the implementation of these technologies in the SPT-3G receiver as well as the challenges they presented. In late 2017 the implementations of all three of these technologies were modified to optimize total performance. Here, we present the current instrument status of the SPT-3G receiver.

48. Particle physics with the cosmic microwave background with SPT-3G

Author

Avva, S. J., Ade, P.A.R, Ahmed, Z, Anderson, A.J, Aylor, K, Basu Thakur, B, Bender, A.N, Benson, B.A, Bleem, L.E, Bocquet, S, Bryant, L, Carlstrom, J.E, Carter, F.W, Cecil, T.W, Chang, C.L, Crawford, T.M, Cukierman, A, de Haan, T, Ding, J, Dobbs, M.A, Dodelson, S, Dutcher, D, Everett, W, Ferguson, K.R, Foster, A, Gallicchio, J, Gambrel, A.E, Gardner, R.W, Groh, J.C, Guns, S, Halverson, N.W, Harke-Hosemann, A.H, Harrington, N.L, Henning, J.W, Holder, G.P, Holzapfel, W.L, Howe, D, Huang, N, Irwin, K.D, Jeong, O.B, Jonas, M, Jones, A, Khaire, T.S, Knox, L, Kofman, A.M, Korman, M, Kubik, D.L, Kuhlmann, S, Kuo, C.-L, Lee, A.T, Lowitz, A.E, Meyer, S.S, Michalik, D, Montgomery, J, Nadolski, A, Natoli, T, Nguyen, H, Noble, G.I, Novosad, V, Padin, S, Pan, Z, Paschos, P, Pearson, J, Posada, C.M, Quan, W, Raghunathan, S, Rahlin, A, Reichardt, C.L, Riebel, D, Ruhl, J.E, Sayre, J.T, Shirokoff, E, Smecher, G, Sobrin, J.A, Stark, A.A, Stephen, J, Story, K.T, Suzuki, A, Thompson, K.L, Tucker, C, Vanderlinde, K, Viera, J.D, Wang, G, Whitehorn, N, Wu, W.L.K, Yefremenko, V, Yoon, K.W, Young, M.R, Avva, S. J., Ade, P.A.R, Ahmed, Z, Anderson, A.J, Aylor, K, Basu Thakur, B, Bender, A.N, Benson, B.A, Bleem, L.E, Bocquet, S, Bryant, L, Carlstrom, J.E, Carter, F.W, Cecil, T.W, Chang, C.L, Crawford, T.M, Cukierman, A, de Haan, T, Ding, J, Dobbs, M.A, Dodelson, S, Dutcher, D, Everett, W, Ferguson, K.R, Foster, A, Gallicchio, J, Gambrel, A.E, Gardner, R.W, Groh, J.C, Guns, S, Halverson, N.W, Harke-Hosemann, A.H, Harrington, N.L, Henning, J.W, Holder, G.P, Holzapfel, W.L, Howe, D, Huang, N, Irwin, K.D, Jeong, O.B, Jonas, M, Jones, A, Khaire, T.S, Knox, L, Kofman, A.M, Korman, M, Kubik, D.L, Kuhlmann, S, Kuo, C.-L, Lee, A.T, Lowitz, A.E, Meyer, S.S, Michalik, D, Montgomery, J, Nadolski, A, Natoli, T, Nguyen, H, Noble, G.I, Novosad, V, Padin, S, Pan, Z, Paschos, P, Pearson, J, Posada, C.M, Quan, W, Raghunathan, S, Rahlin, A, Reichardt, C.L, Riebel, D, Ruhl, J.E, Sayre, J.T, Shirokoff, E, Smecher, G, Sobrin, J.A, Stark, A.A, Stephen, J, Story, K.T, Suzuki, A, Thompson, K.L, Tucker, C, Vanderlinde, K, Viera, J.D, Wang, G, Whitehorn, N, Wu, W.L.K, Yefremenko, V, Yoon, K.W, and Young, M.R

Abstract

The cosmic microwave background (CMB) encodes information about the content and evolution of the universe. The presence of light, weakly interacting particles impacts the expansion history of the early universe, which alters the temperature and polarization anisotropies of the CMB. In this way, current measurements of the CMB place interesting constraints on the neutrino energy density and mass, as well as on the abundance of other possible light relativistic particle species. We present the status of an on-going 1500 sq. deg. survey with the SPT-3G receiver, a new mm-wavelength camera on the 10-m diameter South Pole Telescope (SPT). The SPT-3G camera consists of 16,000 superconducting transition edge sensors, a 10x increase over the previous generation camera, which allows it to map the CMB with an unprecedented combination of sensitivity and angular resolution. We highlight projected constraints on the abundance of sterile neutrinos and the sum of the neutrino masses for the SPT-3G survey, which could help determine the neutrino mass hierarchy....

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