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Correction to: Optimal deterministic algorithm generation

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Journal of Global Optimization 2018年第2期73卷 465-465页

作者： Mitsos, Alexander Najman, Jaromił Kevrekidis, Ioannis G. AVT Process Systems Engineering (SVT) RWTH Aachen University Aachen Germany Department of Chemical and Biological Engineering and Program in Applied and Computational Mathematics Princeton University Princeton USA IAS-TUM Garching and Zuse Institut FU Berlin Berlin Germany Departments of Chemical and Biomolecular Engineering Applied Mathematics and Statistics and Urology Johns Hopkins University Baltimore USA

Unfortunately, the copyright information of the article in Springerlink appears as “©  Springer Science+Business Media, LLC, part of Springer Nature 2018” this has been corrected to “©  ...

Unfortunately, the copyright information of the article in Springerlink appears as “© Springer Science+Business Media, LLC, part of Springer Nature 2018” this has been corrected to “© The Author(s) 2018.”

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The atacama cosmology telescope: DR5 maps of 18000 square degrees of the microwave sky from ACT 2008-2018 data

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arXiv 2020年

作者： 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 Dünner, Rolando Fox, Anna E. Gallardo, Patricio A. Halpern, Mark Han, Dongwon Hasselfield, Matthew Hill, J. Colin Hilton, Gene C. Hilton, Matt Hincks, Adam D. Hložek, Renée 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 Sifón, Cristóbal 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 Center for Computational Astrophysics Flatiron Institute New YorkNY10010 United States Department of Astrophysical Sciences Peyton Hall Princeton University PrincetonNJ08544 United States Joseph Henry Laboratories of Physics Jadwin Hall Princeton University PrincetonNJ08544 United States Department of Physics and Astronomy Haverford College HaverfordPA19041 United States Laboratoire de l’Accélérateur Linéaire Univ. Paris-Sud CNRS/IN2P3 Université Paris-Saclay Orsay France NASA/Goddard Space Flight Center GreenbeltMD20771 United States Physics and Astronomy Department Stony Brook University Stony BrookNY11794 United States Astrophysics Research Centre University of KwaZulu-Natal Westville Campus Durban4041 South Africa Department of Physics California Institute of Technology PasadenaCA91125 United States Instituto de Física Pontificia Universidad Católica de Valparaíso Chile Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Berkeley Center for Cosmological Physics University of California BerkeleyCA94720 United States School of Physics and Astronomy Cardiff University The Parade Cardiff WalesCF24 3AA United Kingdom Department of Physics University of Milano-Bicocca Piazza della Scienza 3 MilanoMI20126 Italy Astrophysics Research Centre School of Mathematics Statistics and Computer Science University of KwaZulu-Natal Durban4041 South Africa Department of Physics and Astronomy Rutgers State University of New Jersey PiscatawayNJ08854-8019 United States StanfordCA United States Instituto de Astrofísica and Centro de Astro-Ingeniería Facultad de Física Pontificia Universidad Católica de Chile Av. Vicuña Mackenna 4860 Macul Santiago7820436 Chile Department of Physics Cornell University IthacaNY14853 United States Department of Astronomy Cornell University IthacaNY14853 United States Dept. of Physics and Astronomy Johns Hopkins University 3400 N. Charles St. BaltimoreMD21218 United States NIST Q

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 > 5σ, 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 are available on LAMBDA at https://***/product/act/actpol_prod_***. There is also a web atlas at https://***/public/snaess/actpol/dr5/atlas. © 2020, CC0.

关键词： Galaxies

Cross-correlation of DES Y3 lensing and ACT/Planck thermal Sunyaev Zel'dovich Effect II: Modeling and constraints on halo pressure profiles

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arXiv 2021年

作者： Pandey, S. Gatti, M. Baxter, E. Hill, J.C. Fang, X. Doux, C. Giannini, G. Raveri, M. DeRose, J. Huang, H. Moser, E. Battaglia, N. Alarcon, A. Amon, A. Becker, M. Campos, A. Chang, C. Chen, R. Choi, A. Eckert, K. Elvin-Poole, J. Everett, S. Ferte, A. Harrison, I. Maccrann, N. McCullough, J. Myles, J. Navarro Alsina, A. Prat, J. Rollins, R.P. Sanchez, C. Shin, T. Troxel, M. Tutusaus, I. Yin, B. Aguena, M. Allam, S. Andrade-Oliveira, F. Bernstein, G.M. Bertin, E. Bolliet, B. Bond, J.R. Brooks, D. Calabrese, E. Carnero Rosell, A. Carrasco Kind, M. Carretero, J. Cawthon, R. Costanzi, M. Crocce, M. da Costa, L.N. Pereira, M.E.S. De Vicente, J. Desai, S. Diehl, H.T. Dietrich, J.P. Doel, P. Dunkley, J. Everett, S. Evrard, A.E. Ferraro, S. Ferrero, I. Flaugher, B. Fosalba, P. García-Bellido, J. Gaztanaga, E. Gerdes, D.W. Giannantonio, T. Gruen, D. Gruendl, R.A. Gschwend, J. Gutierrez, G. Herner, K. Hincks, A.D. Hinton, S.R. Hollowood, D.L. Honscheid, K. Hughes, J.P. Huterer, D. Jain, B. James, D.J. Jeltema, T. Krause, E. Kuehn, K. Lahav, O. Lima, M. Lokken, M. Madhavacheril, M.S. Maia, M.A.G. McMahon, J.J. Melchior, P. Menanteau, F. Miquel, R. Mohr, J.J. Moodley, K. Morgan, R. Nati, F. Niemack, M.D. Page, L. Palmese, A. Paz-Chinchón, F. Pieres, A. Plazas Malagón, A.A. Rodriguez-Monroy, M. Romer, A.K. Sanchez, E. Scarpine, V. Schaan, E. Serrano, S. Sevilla-Noarbe, I. Sheldon, E. Sherwin, B.D. Sifón, C. Smith, M. Soares-Santos, M. Spergel, D. Suchyta, E. Swanson, M.E.C. Tarle, G. Thomas, D. To, C. Varga, T.N. Weller, J. Wollack, E.J. Xu, Z. Department of Physics and Astronomy University of Pennsylvania PhiladelphiaPA19104 United States Institute for Astronomy University of Hawai'i 2680 Woodlawn Drive HonoluluHI96822 United States Department of Physics Columbia University New YorkNY10027 United States Center for Computational Astrophysics Flatiron Institute New YorkNY10010 United States Department of Astronomy Steward Observatory University of Arizona 933 North Cherry Avenue TucsonAZ85721-0065 United States The Barcelona Institute of Science and Technology Campus UAB Bellaterra Barcelona08193 Spain Lawrence Berkeley National Laboratory 1 Cyclotron Road BerkeleyCA94720 United States Department of Physics University of Arizona TucsonAZ85721 United States Department of Astronomy Cornell University IthacaNY14853 United States Argonne National Laboratory 9700 South Cass Avenue LemontIL60439 United States Kavli Institute for Particle Astrophysics & Cosmology Stanford University P. O. Box 2450 StanfordCA94305 United States Department of Physics Carnegie Mellon University PittsburghPA15312 United States Department of Astronomy and Astrophysics University of Chicago ChicagoIL60637 United States Kavli Institute for Cosmological Physics University of Chicago ChicagoIL60637 United States Department of Physics Duke University DurhamNC27708 United States Center for Cosmology and Astro-Particle Physics The Ohio State University ColumbusOH43210 United States Department of Physics The Ohio State University ColumbusOH43210 United States Anta Cruz Institute for Particle Physics Santa CruzCA95064 United States Jet Propulsion Laboratory California Institute of Technology 4800 Oak Grove Dr. PasadenaCA91109 United States Department of Physics University of Oxford Denys Wilkinson Building Keble Road OxfordOX1 3RH United Kingdom Jodrell Bank Center for Astrophysics School of Physics and Astronomy University of Manchester Oxford Road ManchesterM13 9PL United Kingdo

Hot, ionized gas leaves an imprint on the cosmic microwave background via the thermal Sunyaev Zel'dovich (tSZ) effect. The cross-correlation of gravitational lensing (which traces the projected mass) with the tSZ effect (which traces the projected gas pressure) is a powerful probe of the thermal state of ionized baryons throughout the Universe, and is sensitive to effects such as baryonic feedback. In a companion paper (Gatti et al. 2021), we present tomographic measurements and validation tests of the cross-correlation between galaxy shear measurements from the first three years of observations of the Dark Energy Survey, and tSZ measurements from a combination of Atacama Cosmology Telescope and Planck observations. In this work, we use the same measurements to constrain models for the pressure profiles of halos across a wide range of halo mass and redshift. We find evidence for reduced pressure in low mass halos, consistent with predictions for the effects of feedback from active galactic nuclei. We infer the hydrostatic mass bias (B ≡ M500c/MSZ) from our measurements, finding B = 1.8 ± 0.1 when adopting the Planck-preferred cosmological parameters. We additionally find that our measurements are consistent with a non-zero redshift evolution of B, with the correct sign and sufficient magnitude to explain the mass bias necessary to reconcile cluster count measurements with the Planck-preferred cosmology. Our analysis introduces a model for the impact of intrinsic alignments (IA) of galaxy shapes on the shear-tSZ correlation. We show that IA can have a significant impact on these correlations at current noise levels. © 2021, CC BY.

关键词： Pressure effects

The knowledge gradient for sequential decision making with stochastic binary feedbacks 33

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The knowledge gradient for sequential decision making with s...

33rd International Conference on Machine Learning, ICML 2016

作者： Wang, Yingfei Wang, Chu Powell, Warren Department of Computer Science Princeton University PrincetonNJ08540 United States Program in Applied and Computational Mathematics Princeton University PrincetonNJ08544 United States Department of Operations Research and Financial Engineering Princeton University PrincetonNJ08544 United States

ISBN: (纸本)9781510829008

We consider the problem of sequentially making decisions that are rewarded by "successes" and "failures" which can be predicted through an unknown relationship that depends on a partially controllable vector of attributes for each instance. The learner takes an active role in selecting samples from the instance pool. The goal is to maximize the probability of success, either after the offline training phase or minimizing regret in online learning. Our problem is motivated by real-world applications where observations are time consuming and/or expensive. With the adaptation of an online Bayesian linear classifier, we develop a knowledge-gradient type policy to guide the experiment by maximizing the expected value of information of labeling each alternative, in order to reduce the number of expensive physical experiments. We provide a finite-time analysis of the estimated error and demonstrate the performance of the proposed algorithm on both synthetic problems and benchmark UCI datasets.

关键词： Benchmarking

Cross-correlation of DES Y3 lensing and ACT/Planck thermal Sunyaev Zeld'ovich Effect I: Measurements, systematics tests, and feedback model constraints

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arXiv 2021年

作者： Gatti, Marco Pandey, S. Baxter, E. Hill, J.C. Moser, E. Raveri, M. Fang, X. DeRose, J. Giannini, G. Doux, C. Huang, H. Battaglia, N. Alarcon, A. Amon, A. Becker, M. Campos, A. Chang, C. Chen, R. Choi, A. Eckert, K. Elvin-Poole, J. Everett, S. Ferte, A. Harrison, I. Maccrann, N. McCullough, J. Myles, J. Alsina, A. Navarro Prat, J. Rollins, R.P. Sanchez, C. Shin, T. Troxel, M. Tutusaus, I. Yin, B. Abbott, T. Aguena, M. Allam, S. Andrade-Oliveira, F. Annis, J. Bernstein, G. Bertin, E. Bolliet, B. Bond, J.R. Brooks, D. Burke, D.L. Calabrese, E. Rosell, A. Carnero Kind, M. Carrasco Carretero, J. Cawthon, R. Costanzi, M. Crocce, M. da Costa, L.N. da Silva Pereira, M.E. de Vicente, J. Desai, S. Diehl, H.T. Dietrich, J.P. Doel, P. Dunkley, J. Evrard, A.E. Ferraro, S. Ferrero, I. Flaugher, B. Fosalba, P. Frieman, J. García-Bellido, J. Gaztanaga, E. Gerdes, D.W. Giannantonio, T. Gruen, D. Gruendl, R.A. Gschwend, J. Gutierrez, G. Herner, K. Hincks, A.D. Hinton, S.R. Hollowood, D.L. Honscheid, K. Hughes, J.P. Huterer, D. Jain, B. James, D.J. Krause, E. Kuehn, K. Kuropatkin, N. Lahav, O. Lidman, C. Lima, M. Lokken, M. Madhavacheril, M.S. Maia, M.A.G. Marshall, J.L. McMahon, J.J. Melchior, P. Moodley, K. Mohr, J.J. Morgan, R. Nati, F. Niemack, M.D. Page, L. Palmese, A. Paz-Chinchón, F. Pieres, A. Malagón, A.A. Plazas Rodriguez-Monroy, M. Romer, A.K. Sanchez, E. Scarpine, V. Schaan, E. Secco, L.F. Serrano, S. Sheldon, E. Sherwin, B.D. Sifón, C. Smith, M. Soares-Santos, M. Spergel, D. Suchyta, E. Tarle, G. Thomas, D. To, C. Tucker, D.L. Varga, T.N. Weller, J. Wilkinson, R.D. Wollack, E.J. Xu, Z. Department of Physics and Astronomy University of Pennsylvania PhiladelphiaPA19104 United States Institute for Astronomy University of Hawai'i 2680 Woodlawn Drive HonoluluHI96822 United States Department of Physics Columbia University New YorkNY10027 United States Center for Computational Astrophysics Flatiron Institute New YorkNY10010 United States Department of Astronomy Cornell University IthacaNY14853 United States Department of Astronomy/Steward Observatory University of Arizona 933 North Cherry Avenue TucsonAZ85721-0065 United States Lawrence Berkeley National Laboratory 1 Cyclotron Road BerkeleyCA94720 United States The Barcelona Institute of Science and Technology Campus UAB Bellaterra Barcelona08193 Spain Department of Physics University of Arizona TucsonAZ85721 United States Argonne National Laboratory 9700 South Cass Avenue LemontIL60439 United States Kavli Institute for Particle Astrophysics & Cosmology Stanford University P. O. Box 2450 StanfordCA94305 United States Department of Physics Carnegie Mellon University PittsburghPA15312 United States Department of Astronomy and Astrophysics University of Chicago ChicagoIL60637 United States Kavli Institute for Cosmological Physics University of Chicago ChicagoIL60637 United States Department of Physics Duke University DurhamNC27708 United States Center for Cosmology and Astro-Particle Physics The Ohio State University ColumbusOH43210 United States Department of Physics The Ohio State University ColumbusOH43210 United States Santa Cruz Institute for Particle Physics Santa CruzCA95064 United States Jet Propulsion Laboratory California Institute of Technology 4800 Oak Grove Dr. PasadenaCA91109 United States Department of Physics University of Oxford Denys Wilkinson Building Keble Road OxfordOX1 3RH United Kingdom Jodrell Bank Center for Astrophysics School of Physics and Astronomy University of Manchester Oxford Road ManchesterM13 9PL United Kingdo

We present a tomographic measurement of the cross-correlation between thermal Sunyaev-Zeldovich (tSZ) maps from Planck and the Atacama Cosmology Telescope (ACT) and weak galaxy lensing shears measured during the first three years of observations of the Dark Energy Survey (DES Y3). This correlation is sensitive to the thermal energy in baryons over a wide redshift range, and is therefore a powerful probe of astrophysical feedback. We detect the correlation at a statistical significance of 21σ, the highest significance to date. We examine the tSZ maps for potential contaminants, including cosmic infrared background (CIB) and radio sources, finding that CIB has a substantial impact on our measurements and must be taken into account in our analysis. We use the cross-correlation measurements to test different feedback models. In particular, we model the tSZ using several different pressure profile models calibrated against hydrodynamical simulations. Our analysis marginalises over redshift uncertainties, shear calibration biases, and intrinsic alignment effects. We also marginalise over Ωm and σ8 using Planck or DES priors. We find that the data prefers the model with a low amplitude of the pressure profile at small scales, compatible with a scenario with strong AGN feedback and ejection of gas from the inner part of the halos. When using a more flexible model for the shear profile, constraints are weaker, and the data cannot discriminate between different baryonic prescriptions. Copyright © 2021, The Authors. All rights reserved.

关键词： Radio astronomy

Effect of non-Gaussian lensing deflections on CMB lensing measurements

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Physical Review D 2018年第12期98卷 123510-123510页

作者： Vanessa Böhm Blake D. Sherwin Jia Liu J. Colin Hill Marcel Schmittfull Toshiya Namikawa Berkeley Center for Cosmological Physics University of California Berkeley California 94720 USA Lawrence Berkeley National Laboratory 1 Cyclotron Road Berkeley California 93720 USA Department of Applied Mathematics and Theoretical Physics University of Cambridge Wilberforce Road Cambridge CB3 0WA United Kingdom Department of Astrophysical Sciences Princeton University Princeton New Jersey 08544 USA Center for Computational Astrophysics Flatiron Institute 162 5th Avenue New York New York 10010 USA Institute for Advanced Study Einstein Drive Princeton New Jersey 08540 USA Leung Center for Cosmology and Particle Astrophysics National Taiwan University Taipei 10617 Taiwan

We investigate the impact of non-Gaussian lensing deflections on measurements of the CMB lensing power spectrum. We find that the false assumption of their Gaussianity significantly biases these measurements in current and future experiments at the percent level. The bias is detected by comparing CMB lensing reconstructions from simulated CMB data lensed with Gaussian deflection fields to reconstructions from simulations lensed with fully non-Gaussian deflection fields. The non-Gaussian deflections are produced by ray tracing through snapshots of an N-body simulation and capture both the non-Gaussianity induced by nonlinear structure formation and by multiple correlated deflections. We find that the amplitude of the measured bias can be modeled with analytic expressions for a lensing bispectrum-induced bias derived by Böhm et al. in 2016 when post-Born corrections are included in the lensing bispectrum model. The bias is largest in temperature-based measurements, where it is detected with a significance of 2.84σ in the power spectrum of reconstructed convergence fields. Cross-correlating the reconstruction with the noiseless input convergence fields results in a 5.21σ detection. We do not find evidence for the bias in measurements from a combination of polarization fields (EB,EB). We argue that this non-Gaussian bias should be even more important for measurements of cross-correlations of CMB lensing with low-redshift tracers of large-scale structure.

关键词： Cosmic microwave background Evolution of the Universe Gravitational lenses Large scale structure of the Universe Sky surveys

Search for continuous gravitational waves from 20 accreting millisecond x-ray pulsars in O3 LIGO data

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Physical Review D 2022年第2期105卷 022002-022002页

作者： R. Abbott T. D. Abbott F. Acernese K. Ackley C. Adams N. Adhikari R. X. Adhikari V. B. Adya C. Affeldt D. Agarwal M. Agathos K. Agatsuma N. Aggarwal O. D. Aguiar L. Aiello A. Ain T. Akutsu S. Albanesi A. Allocca P. A. Altin A. Amato C. Anand S. Anand A. Ananyeva S. B. Anderson W. G. Anderson M. Ando T. Andrade N. Andres T. Andrić S. V. Angelova S. Ansoldi J. M. Antelis S. Antier S. Appert Koji Arai Koya Arai Y. Arai S. Araki A. Araya M. C. Araya J. S. Areeda M. Arène N. Aritomi N. Arnaud S. M. Aronson K. G. Arun H. Asada Y. Asali G. Ashton Y. Aso M. Assiduo S. M. Aston P. Astone F. Aubin C. Austin S. Babak F. Badaracco M. K. M. Bader C. Badger S. Bae Y. Bae A. M. Baer S. Bagnasco Y. Bai L. Baiotti J. Baird R. Bajpai M. Ball G. Ballardin S. W. Ballmer A. Balsamo G. Baltus S. Banagiri D. Bankar J. C. Barayoga C. Barbieri B. C. Barish D. Barker P. Barneo F. Barone B. Barr L. Barsotti M. Barsuglia D. Barta J. Bartlett M. A. Barton I. Bartos R. Bassiri A. Basti M. Bawaj J. C. Bayley A. C. Baylor M. Bazzan B. Bécsy V. M. Bedakihale M. Bejger I. Belahcene V. Benedetto D. Beniwal T. F. Bennett J. D. Bentley M. BenYaala F. Bergamin B. K. Berger S. Bernuzzi D. Bersanetti A. Bertolini J. Betzwieser D. Beveridge R. Bhandare U. Bhardwaj D. Bhattacharjee S. Bhaumik I. A. Bilenko G. Billingsley S. Bini R. Birney O. Birnholtz S. Biscans M. Bischi S. Biscoveanu A. Bisht B. Biswas M. Bitossi M.-A. Bizouard J. K. Blackburn C. D. Blair D. G. Blair R. M. Blair F. Bobba N. Bode M. Boer G. Bogaert M. Boldrini L. D. Bonavena F. Bondu E. Bonilla R. Bonnand P. Booker B. A. Boom R. Bork V. Boschi N. Bose S. Bose V. Bossilkov V. Boudart Y. Bouffanais A. Bozzi C. Bradaschia P. R. Brady A. Bramley A. Branch M. Branchesi J. E. Brau M. Breschi T. Briant J. H. Briggs A. Brillet M. Brinkmann P. Brockill A. F. Brooks J. Brooks D. D. Brown S. Brunett G. Bruno R. Bruntz J. Bryant T. Bulik H. J. Bulten A. Buonanno R. Buscicchio D. Buskulic C. Buy R. L. Byer L. Cadonati G. Cagnoli C. Cahillane J. Calderón Bustillo J. D. Callaghan T. A. Callister E. Ca LIGO Laboratory California Institute of Technology Pasadena California 91125 USA Louisiana State University Baton Rouge Louisiana 70803 USA Dipartimento di Farmacia Università di Salerno I-84084 Fisciano Salerno Italy INFN Sezione di Napoli Complesso Universitario di Monte S. Angelo I-80126 Napoli Italy OzGrav School of Physics & Astronomy Monash University Clayton 3800 Victoria Australia LIGO Livingston Observatory Livingston Louisiana 70754 USA University of Wisconsin-Milwaukee Milwaukee Wisconsin 53201 USA OzGrav Australian National University Canberra Australian Capital Territory 0200 Australia Max Planck Institute for Gravitational Physics (Albert Einstein Institute) D-30167 Hannover Germany Leibniz Universität Hannover D-30167 Hannover Germany Inter-University Centre for Astronomy and Astrophysics Pune 411007 India University of Cambridge Cambridge CB2 1TN United Kingdom Theoretisch-Physikalisches Institut Friedrich-Schiller-Universität Jena D-07743 Jena Germany University of Birmingham Birmingham B15 2TT United Kingdom Center for Interdisciplinary Exploration & Research in Astrophysics (CIERA) Northwestern University Evanston Illinois 60208 USA Instituto Nacional de Pesquisas Espaciais 12227-010 São José dos Campos São Paulo Brazil Gravity Exploration Institute Cardiff University Cardiff CF24 3AA United Kingdom INFN Sezione di Pisa I-56127 Pisa Italy Gravitational Wave Science Project National Astronomical Observatory of Japan (NAOJ) Mitaka City Tokyo 181-8588 Japan Advanced Technology Center National Astronomical Observatory of Japan (NAOJ) Mitaka City Tokyo 181-8588 Japan INFN Sezione di Torino I-10125 Torino Italy Università di Napoli “Federico II” Complesso Universitario di Monte S. Angelo I-80126 Napoli Italy Université de Lyon Université Claude Bernard Lyon 1 CNRS Institut Lumière Matière F-69622 Villeurbanne France Department of Physics The University of Tokyo Bunkyo-ku Tokyo 113-0033 Japan Research Center for the Early Un

Results are presented of searches for continuous gravitational waves from 20 accreting millisecond x-ray pulsars with accurately measured spin frequencies and orbital parameters, using data from the third observing run of the Advanced LIGO and Advanced Virgo detectors. The search algorithm uses a hidden Markov model, where the transition probabilities allow the frequency to wander according to an unbiased random walk, while the J-statistic maximum-likelihood matched filter tracks the binary orbital phase. Three narrow subbands are searched for each target, centered on harmonics of the measured spin frequency. The search yields 16 candidates, consistent with a false alarm probability of 30% per subband and target searched. These candidates, along with one candidate from an additional target-of-opportunity search done for SAX J1808.4−3658, which was in outburst during one month of the observing run, cannot be confidently associated with a known noise source. Additional follow-up does not provide convincing evidence that any are a true astrophysical signal. When all candidates are assumed nonastrophysical, upper limits are set on the maximum wave strain detectable at 95% confidence, h095%. The strictest constraint is h095%=4.7×10−26 from IGR J17062−6143. Constraints on the detectable wave strain from each target lead to constraints on neutron star ellipticity and r-mode amplitude, the strictest of which are ε95%=3.1×10−7 and α95%=1.8×10−5 respectively. This analysis is the most comprehensive and sensitive search of continuous gravitational waves from accreting millisecond x-ray pulsars to date.

关键词： Gravitational waves Binary stars Neutron stars & pulsars

All-sky, all-frequency directional search for persistent gravitational waves from Advanced LIGO’s and Advanced Virgo’s first three observing runs

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Physical Review D 2022年第12期105卷 122001-122001页

作者： R. Abbott T. D. Abbott F. Acernese K. Ackley C. Adams N. Adhikari R. X. Adhikari V. B. Adya C. Affeldt D. Agarwal M. Agathos K. Agatsuma N. Aggarwal O. D. Aguiar L. Aiello A. Ain P. Ajith T. Akutsu S. Albanesi A. Allocca P. A. Altin A. Amato C. Anand S. Anand A. Ananyeva S. B. Anderson W. G. Anderson M. Ando T. Andrade N. Andres T. Andrić S. V. Angelova S. Ansoldi J. M. Antelis S. Antier S. Appert Koji Arai Koya Arai Y. Arai S. Araki A. Araya M. C. Araya J. S. Areeda M. Arène N. Aritomi N. Arnaud S. M. Aronson K. G. Arun H. Asada Y. Asali G. Ashton Y. Aso M. Assiduo S. M. Aston P. Astone F. Aubin C. Austin S. Babak F. Badaracco M. K. M. Bader C. Badger S. Bae Y. Bae A. M. Baer S. Bagnasco Y. Bai L. Baiotti J. Baird R. Bajpai M. Ball G. Ballardin S. W. Ballmer A. Balsamo G. Baltus S. Banagiri D. Bankar J. C. Barayoga C. Barbieri B. C. Barish D. Barker P. Barneo F. Barone B. Barr L. Barsotti M. Barsuglia D. Barta J. Bartlett M. A. Barton I. Bartos R. Bassiri A. Basti M. Bawaj J. C. Bayley A. C. Baylor M. Bazzan B. Bécsy V. M. Bedakihale M. Bejger I. Belahcene V. Benedetto D. Beniwal T. F. Bennett J. D. Bentley M. BenYaala F. Bergamin B. K. Berger S. Bernuzzi D. Bersanetti A. Bertolini J. Betzwieser D. Beveridge R. Bhandare U. Bhardwaj D. Bhattacharjee S. Bhaumik I. A. Bilenko G. Billingsley S. Bini R. Birney O. Birnholtz S. Biscans M. Bischi S. Biscoveanu A. Bisht B. Biswas M. Bitossi M.-A. Bizouard J. K. Blackburn C. D. Blair D. G. Blair R. M. Blair F. Bobba N. Bode M. Boer G. Bogaert M. Boldrini L. D. Bonavena F. Bondu E. Bonilla R. Bonnand P. Booker B. A. Boom R. Bork V. Boschi N. Bose S. Bose V. Bossilkov V. Boudart Y. Bouffanais A. Bozzi C. Bradaschia P. R. Brady A. Bramley A. Branch M. Branchesi J. E. Brau M. Breschi T. Briant J. H. Briggs A. Brillet M. Brinkmann P. Brockill A. F. Brooks J. Brooks D. D. Brown S. Brunett G. Bruno R. Bruntz J. Bryant T. Bulik H. J. Bulten A. Buonanno R. Buscicchio D. Buskulic C. Buy R. L. Byer L. Cadonati G. Cagnoli C. Cahillane J. Calderón Bustillo J. D. Callaghan T. A. Callis LIGO Laboratory California Institute of Technology Pasadena California 91125 USA Louisiana State University Baton Rouge Louisiana 70803 USA Dipartimento di Farmacia Università di Salerno I-84084 Fisciano Salerno Italy INFN Sezione di Napoli Complesso Universitario di Monte S. Angelo I-80126 Napoli Italy OzGrav School of Physics & Astronomy Monash University Clayton 3800 Victoria Australia LIGO Livingston Observatory Livingston Louisiana 70754 USA University of Wisconsin-Milwaukee Milwaukee Wisconsin 53201 USA OzGrav Australian National University Canberra Australian Capital Territory 0200 Australia Max Planck Institute for Gravitational Physics (Albert Einstein Institute) D-30167 Hannover Germany Leibniz Universität Hannover D-30167 Hannover Germany Inter-University Centre for Astronomy and Astrophysics Pune 411007 India University of Cambridge Cambridge CB2 1TN United Kingdom Theoretisch-Physikalisches Institut Friedrich-Schiller-Universität Jena D-07743 Jena Germany University of Birmingham Birmingham B15 2TT United Kingdom Center for Interdisciplinary Exploration & Research in Astrophysics (CIERA) Northwestern University Evanston Illinois 60208 USA Instituto Nacional de Pesquisas Espaciais 12227-010 São José dos Campos São Paulo Brazil Gravity Exploration Institute Cardiff University Cardiff CF24 3AA United Kingdom INFN Sezione di Pisa I-56127 Pisa Italy International Centre for Theoretical Sciences Tata Institute of Fundamental Research Bengaluru 560089 India Gravitational Wave Science Project National Astronomical Observatory of Japan (NAOJ) Mitaka City Tokyo 181-8588 Japan Advanced Technology Center National Astronomical Observatory of Japan (NAOJ) Mitaka City Tokyo 181-8588 Japan INFN Sezione di Torino I-10125 Torino Italy Università di Napoli “Federico II” Complesso Universitario di Monte S. Angelo I-80126 Napoli Italy Université de Lyon Université Claude Bernard Lyon 1 CNRS Institut Lumière Matière F-69622 Villeurbanne France De

We present the first results from an all-sky all-frequency (ASAF) search for an anisotropic stochastic gravitational-wave background using the data from the first three observing runs of the Advanced LIGO and Advanced Virgo detectors. Upper limit maps on broadband anisotropies of a persistent stochastic background were published for all observing runs of the LIGO-Virgo detectors. However, a broadband analysis is likely to miss narrowband signals as the signal-to-noise ratio of a narrowband signal can be significantly reduced when combined with detector output from other frequencies. Data folding and the computationally efficient analysis pipeline, PyStoch, enable us to perform the radiometer map-making at every frequency bin. We perform the search at 3072 HEALPix equal area pixels uniformly tiling the sky and in every frequency bin of width 1/32 Hz in the range 20–1726 Hz, except for bins that are likely to contain instrumental artefacts and hence are notched. We do not find any statistically significant evidence for the existence of narrowband gravitational-wave signals in the analyzed frequency bins. Therefore, we place 95% confidence upper limits on the gravitational-wave strain for each pixel-frequency pair, the limits are in the range (0.030−9.6)×10−24. In addition, we outline a method to identify candidate pixel-frequency pairs that could be followed up by a more sensitive (and potentially computationally expensive) search, e.g., a matched-filtering-based analysis, to look for fainter nearly monochromatic coherent signals. The ASAF analysis is inherently independent of models describing any spectral or spatial distribution of power. We demonstrate that the ASAF results can be appropriately combined over frequencies and sky directions to successfully recover the broadband directional and isotropic results.

关键词： Gravitational wave detection Gravitational waves

APOGEE chemical abundance patterns of the massive milky way satellites

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arXiv 2021年

作者： Hasselquist, Sten Hayes, Christian R. Lian, Jianhui Weinberg, David H. Zasowski, Gail Horta, Danny Beaton, Rachael Feuillet, Diane K. Garro, Elisa R. Gallart, Carme Smith, Verne V. Holtzman, Jon A. Minniti, Dante Lacerna, Ivan Shetrone, Matthew Jönsson, Henrik Cioni, Maria-Rosa L. Fillingham, Sean P. Cunha, Katia OĆonnell, Robert Fernández-Trincado, José G. Muñoz, Ricardo R. Schiavon, Ricardo Almeida, Andres Anguiano, Borja Beers, Timothy C. Bizyaev, Dmitry Brownstein, Joel R. Cohen, Roger E. Frinchaboy, Peter García-Hernández, D.A. Geisler, Doug Lane, Richard R. Majewski, Steven R. Nidever, David L. Nitschelm, Christian Povick, Joshua Price-Whelan, Adrian Roman-Lopes, Alexandre Rosado, Margarita Sobeck, Jennifer Stringfellow, Guy Valenzuela, Octavio Villanova, Sandro Vincenzo, Fiorenzo Department of Physics & Astronomy University of Utah Salt Lake CityUT84112 United States NSF Astronomy and Astrophysics Department of Astronomy University of Virginia CharlottesvilleVA22904 United States Lund Observatory Department of Astronomy and Theoretical Physics Box 43 LundSE-221 00 Sweden Department of Physics Montana State University P.O. Box 173840 BozemanMT59717-3840 United States Department of Astrophysical Sciences Princeton University 4 Ivy Lane PrincetonNJ08544 United States Departamento de Ciencias Físicas Facultad de Ciencias Exactas Universidad Andres Bello Fernández Concha 700 Las Condes Santiago Chile Vatican Observatory Vatican City StateV-00120 Italy Department of Physics JINA Center for the Evolution of the Elements University of Notre Dame Notre DameIN46556 United States Steward Observatory The University of Arizona TucsonAZ85719 United States Observatório Nacional So Cristóvao RJ Rio de Janeiro20921-400 Brazil Instituto de Astronomía y Ciencias Planetarias Universidad de Atacama Copayapu 485 Copiapó Chile Millennium Institute of Astrophysics Nuncio Monsenor Sotero Sanz 100 Of. 104 Providencia Santiago Chile Departamento de Astronomía Universidad de Concepcion Casilla 160-C Chile Instituto de Investigación Multidisciplinario en Ciencia y Tecnología Universidad de La Serena Avenida Raúl Bitrán S/N La Serena Chile Departamento de Física y Astronomía Facultad de Ciencias Universidad de La Serena Av. Juan Cisternas 1200 La Serena Chile Department of Astronomy New Mexico State University Las CrucesNM88003 United States Department of Astronomy The Ohio State University 140 W. 18th Ave. ColumbusOH43210 United States Centro de Investigación en Astronomía Universidad Bernardo O’Higgins Avenida Viel 1497 Santiago Chile Universidad de Antofagasta Avenida Angamos 601 Antofagasta1270300 Chile Astrophysics Research Institute Liverpool John Moores University IC2 Liverpool Science Park 146 Brownlow Hill Liver

The SDSS-IV Apache Point Observatory Galactic Evolution Experiment (APOGEE) survey has obtained high-resolution spectra for thousands of red giant stars distributed among the massive satellite galaxies of the Milky Way (MW): the Large and Small Magellanic Clouds (LMC/SMC), the Sagittarius Dwarf (Sgr), Fornax (Fnx), and the now fully disrupted Gaia Sausage/Enceladus (GSE) system. We present and analyze the APOGEE chemical abundance patterns of each galaxy to draw robust conclusions about their star formation histories, by quantifying the relative abundance trends of multiple elements (C, N, O, Mg, Al, Si, Ca, Fe, Ni, and Ce), as well as by fitting chemical evolution models to the [α/Fe]-[Fe/H] abundance plane for each galaxy. Results show that the chemical signatures of the starburst in the MCs observed by Nidever et al. in the α-element abundances extend to C+N, Al, and Ni, with the major burst in the SMC occurring some 3-4 Gyr before the burst in the LMC. We find that Sgr and Fnx also exhibit chemical abundance patterns suggestive of secondary star formation epochs, but these events were weaker and earlier (∼ 5-7 Gyr ago) than those observed in the MCs. There is no chemical evidence of a second starburst in GSE, but this galaxy shows the strongest initial star formation as compared to the other four galaxies. All dwarf galaxies had greater relative contributions of AGB stars to their enrichment than the MW. Comparing and contrasting these chemical patterns highlight the importance of galaxy environment on its chemical evolution. © 2021, CC BY.

关键词： Galaxies