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Grant R. Tremblay

Bio: Grant R. Tremblay is an academic researcher from Harvard University. The author has contributed to research in topics: Galaxy & Radio galaxy. The author has an hindex of 39, co-authored 179 publications receiving 9011 citations. Previous affiliations of Grant R. Tremblay include Rochester Institute of Technology & Space Telescope Science Institute.


Papers
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Journal ArticleDOI
Adrian M. Price-Whelan1, B. M. Sipőcz1, Hans Moritz Günther1, P. L. Lim1, Steven M. Crawford1, S. Conseil1, D. L. Shupe1, M. W. Craig1, N. Dencheva1, Adam Ginsburg1, Jacob T VanderPlas1, Larry Bradley1, David Pérez-Suárez1, M. de Val-Borro1, T. L. Aldcroft1, Kelle L. Cruz1, Thomas P. Robitaille1, E. J. Tollerud1, C. Ardelean1, Tomáš Babej1, Y. P. Bach1, Matteo Bachetti1, A. V. Bakanov1, Steven P. Bamford1, Geert Barentsen1, Pauline Barmby1, Andreas Baumbach1, Katherine Berry1, F. Biscani1, Médéric Boquien1, K. A. Bostroem1, L. G. Bouma1, G. B. Brammer1, E. M. Bray1, H. Breytenbach1, H. Buddelmeijer1, D. J. Burke1, G. Calderone1, J. L. Cano Rodríguez1, Mihai Cara1, José Vinícius de Miranda Cardoso1, S. Cheedella1, Y. Copin1, Lia Corrales1, Devin Crichton1, D. DÁvella1, Christoph Deil1, É. Depagne1, J. P. Dietrich1, Axel Donath1, M. Droettboom1, Nicholas Earl1, T. Erben1, Sebastien Fabbro1, Leonardo Ferreira1, T. Finethy1, R. T. Fox1, Lehman H. Garrison1, S. L. J. Gibbons1, Daniel A. Goldstein1, Ralf Gommers1, Johnny P. Greco1, P. Greenfield1, A. M. Groener1, Frédéric Grollier1, A. Hagen1, P. Hirst1, Derek Homeier1, Anthony Horton1, Griffin Hosseinzadeh1, L. Hu1, J. S. Hunkeler1, Ž. Ivezić1, A. Jain1, T. Jenness1, G. Kanarek1, Sarah Kendrew1, Nicholas S. Kern1, Wolfgang Kerzendorf1, A. Khvalko1, J. King1, D. Kirkby1, A. M. Kulkarni1, Ashok Kumar1, Antony Lee1, D. Lenz1, S. P. Littlefair1, Zhiyuan Ma1, D. M. Macleod1, M. Mastropietro1, C. McCully1, S. Montagnac1, Brett M. Morris1, M. Mueller1, Stuart Mumford1, D. Muna1, Nicholas A. Murphy1, Stefan Nelson1, G. H. Nguyen1, Joe Philip Ninan1, M. Nöthe1, S. Ogaz1, Seog Oh1, J. K. Parejko1, N. R. Parley1, Sergio Pascual1, R. Patil1, A. A. Patil1, A. L. Plunkett1, Jason X. Prochaska1, T. Rastogi1, V. Reddy Janga1, J. Sabater1, Parikshit Sakurikar1, Michael Seifert1, L. E. Sherbert1, H. Sherwood-Taylor1, A. Y. Shih1, J. Sick1, M. T. Silbiger1, Sudheesh Singanamalla1, Leo Singer1, P. H. Sladen1, K. A. Sooley1, S. Sornarajah1, Ole Streicher1, P. Teuben1, Scott Thomas1, Grant R. Tremblay1, J. Turner1, V. Terrón1, M. H. van Kerkwijk1, A. de la Vega1, Laura L. Watkins1, B. A. Weaver1, J. Whitmore1, Julien Woillez1, Victor Zabalza1, Astropy Contributors1 
TL;DR: The Astropy project as discussed by the authors is a Python project supporting the development of open-source and openly developed Python packages that provide commonly needed functionality to the astronomical community, including the core package astropy.
Abstract: The Astropy Project supports and fosters the development of open-source and openly developed Python packages that provide commonly needed functionality to the astronomical community. A key element of the Astropy Project is the core package astropy, which serves as the foundation for more specialized projects and packages. In this article, we provide an overview of the organization of the Astropy project and summarize key features in the core package, as of the recent major release, version 2.0. We then describe the project infrastructure designed to facilitate and support development for a broader ecosystem of interoperable packages. We conclude with a future outlook of planned new features and directions for the broader Astropy Project.

4,044 citations

Journal ArticleDOI
Adrian M. Price-Whelan, Brigitta Sipőcz, Hans Moritz Günther, P. L. Lim, Steven M. Crawford, Simon Conseil, David L. Shupe, Matt Craig, N. Dencheva, Adam Ginsburg, Jacob T VanderPlas, Larry Bradley, David Pérez-Suárez, M. de Val-Borro, T. L. Aldcroft, Kelle L. Cruz, Thomas P. Robitaille, Erik J. Tollerud, C. Ardelean, Tomáš Babej, Matteo Bachetti, A. V. Bakanov, Steven P. Bamford, Geert Barentsen, Pauline Barmby, Andreas Baumbach, Katherine Berry, F. Biscani, Médéric Boquien, K. A. Bostroem, L. G. Bouma, G. B. Brammer, Erik Bray, H. Breytenbach, H. Buddelmeijer, Douglas Burke, G. Calderone, J. L. Cano Rodríguez, Mihai Cara, José Vinícius de Miranda Cardoso, S. Cheedella, Y. Copin, Devin Crichton, D. DÁvella, Christoph Deil, Éric Depagne, J. P. Dietrich, Axel Donath, Michael Droettboom, Nicholas Earl, T. Erben, Sebastien Fabbro, Leonardo Ferreira, T. Finethy, R. T. Fox, Lehman H. Garrison, S. L. J. Gibbons, Daniel A. Goldstein, Ralf Gommers, Johnny P. Greco, Perry Greenfield, A. M. Groener, Frédéric Grollier, Alex Hagen, Paul Hirst, Derek Homeier, Anthony Horton, Griffin Hosseinzadeh, L. Hu, J. S. Hunkeler, Željko Ivezić, A. Jain, Tim Jenness, G. Kanarek, Sarah Kendrew, Nicholas S. Kern, Wolfgang Kerzendorf, A. Khvalko, J. King, D. Kirkby, A. M. Kulkarni, Ashok Kumar, Antony Lee, D. Lenz, S. P. Littlefair, Zhiyuan Ma, D. M. Macleod, M. Mastropietro, C. McCully, S. Montagnac, Brett M. Morris, Michael Mueller, Stuart Mumford, Demitri Muna, Nicholas A. Murphy, Stefan Nelson, G. H. Nguyen, Joe Philip Ninan, M. Nöthe, S. Ogaz, Seog Oh, John K. Parejko, N. R. Parley, Sergio Pascual, R. Patil, A. A. Patil, A. L. Plunkett, Jason X. Prochaska, T. Rastogi, V. Reddy Janga, Josep Sabater, Parikshit Sakurikar, Michael Seifert, L. E. Sherbert, H. Sherwood-Taylor, A. Y. Shih, J. Sick, M. T. Silbiger, Sudheesh Singanamalla, Leo Singer, P. H. Sladen, K. A. Sooley, S. Sornarajah, Ole Streicher, Peter Teuben, Scott Thomas, Grant R. Tremblay, J. Turner, V. Terrón, M. H. van Kerkwijk, A. de la Vega, Laura L. Watkins, B. A. Weaver, J. Whitmore, Julien Woillez, Victor Zabalza 
TL;DR: The Astropy project as discussed by the authors is an open-source and openly developed Python packages that provide commonly-needed functionality to the astronomical community, including the core package Astropy, which serves as the foundation for more specialized projects and packages.
Abstract: The Astropy project supports and fosters the development of open-source and openly-developed Python packages that provide commonly-needed functionality to the astronomical community. A key element of the Astropy project is the core package Astropy, which serves as the foundation for more specialized projects and packages. In this article, we provide an overview of the organization of the Astropy project and summarize key features in the core package as of the recent major release, version 2.0. We then describe the project infrastructure designed to facilitate and support development for a broader ecosystem of inter-operable packages. We conclude with a future outlook of planned new features and directions for the broader Astropy project.

2,286 citations

Journal ArticleDOI
The Astropy Collaboration, Adrian M. Price-Whelan, Pey Lian Lim, Nicholas Earl, Nathaniel Starkman, Larry Bradley, David L. Shupe, Aarya A. Patil, Lia Corrales, C. E. Brasseur, M. Nöthe, Axel Donath, Erik Tollerud, Brett M. Morris, Adam Ginsburg, Eero Vaher, B. A. Weaver, James Tocknell, William Jamieson, M. H. van Kerkwijk, Thomas P. Robitaille, Bruce Merry, Matteo Bachetti, H. M. Gunther, Tom Aldcroft, Jaime A. Alvarado-Montes, Anne M. Archibald, A. B'odi, Shreyas Bapat, Geert Barentsen, Juanjo Baz'an, Manish J Biswas, Médéric Boquien, D. J. Burke, D Di Cara, Mihai Cara, Kyle E. Conroy, Simon Conseil, Matt Craig, Robert M. Cross, Kelle L. Cruz, Francesco D'Eugenio, Nadia Dencheva, Hadrien A. R. Devillepoix, J. P. Dietrich, Arthur Eigenbrot, Thomas Erben, Leonardo Ferreira, Daniel Foreman-Mackey, R. T. Fox, Nabil Freij, Suyog Garg, Robel Geda, Lauren Glattly, Yash Gondhalekar, Karl D. Gordon, David Grant, Perry Greenfield, A. M. Groener, S. Guest, Sebastián Gurovich, Rasmus Handberg, Akeem Hart, Zac Hatfield-Dodds, Derek Homeier, Griffin Hosseinzadeh, Tim Jenness, Craig Jones, Prajwel Joseph, J. Bryce Kalmbach, Emir Karamehmetoglu, M. Kaluszy'nski, Michaelann Kelley, Nicholas S. Kern, Wolfgang Kerzendorf, Eric W. Koch, Shankar Kulumani, Antony H. Lee, Chun Ly, Zhiyuan Mao, Conor D. MacBride, Jakob M. Maljaars, Demitri Muna, Nellie Appy Murphy, Henrik Norman, R. G. O'Steen, Kyle A. Oman, Camilla Pacifici, Sergio Pascual, J. Pascual-Granado, Rohit R Patil, G. I. Perren, T. E. Pickering, Tanuja Rastogi, Benjamin R. Roulston, Daniel F Ryan, Eli S. Rykoff, J. Sabater, Parikshit Sakurikar, Jesús Busto Salgado, Aniket Sanghi, Nicholas Saunders, V. G. Savchenko, L. C. Schwardt, Michael Seifert-Eckert, Albert J. Shih, A. S. Jain, G. R. Shukla, J. Sick, Chris Simpson, Sudheesh Singanamalla, Leo Singer, Jaladh Singhal, Manodeep Sinha, B. SipHocz, Lee R. Spitler, David Stansby, Ole Streicher, Jani vSumak, John D. Swinbank, Dan S. Taranu, N. B. Tewary, Grant R. Tremblay, Miguel De Val-Borro, Samuel J. Van Kooten, Zlatan Vasovi'c, Shresth Verma, José Vinícius de Miranda Cardoso, Peter K. G. Williams, Tom J. Wilson, Benjamin Winkel, W. M. Wood-Vasey, Rui Xue, Peter Yoachim, Chenchen Zhang, Andrea Zonca 
TL;DR: Astropy as mentioned in this paper is a Python package that provides commonly needed functionality to the astronomical community, such as astronomy, astronomy, and astronomy data visualization, as well as other related projects and packages.
Abstract: The Astropy Project supports and fosters the development of open-source and openly developed Python packages that provide commonly needed functionality to the astronomical community. A key element of the Astropy Project is the core package astropy, which serves as the foundation for more specialized projects and packages. In this article, we summarize key features in the core package as of the recent major release, version 5.0, and provide major updates on the Project. We then discuss supporting a broader ecosystem of interoperable packages, including connections with several astronomical observatories and missions. We also revisit the future outlook of the Astropy Project and the current status of Learn Astropy. We conclude by raising and discussing the current and future challenges facing the Project.

299 citations

Journal ArticleDOI
09 Jun 2016-Nature
TL;DR: Observations reveal a cold, clumpy accretion flow towards a supermassive black hole fuel reservoir in the nucleus of the Abell 2597 Brightest Cluster Galaxy, a nearby giant elliptical galaxy surrounded by a dense halo of hot plasma.
Abstract: The so-called accretion flow that powers the growth of supermassive black holes in galaxy centres is assumed to be dominated by a smooth, steady flow of very hot plasma, but now observations instead reveal a clumpy accretion of very cold molecular clouds onto a supermassive black hole in the nucleus of a nearby giant elliptical galaxy. The so-called accretion flow that powers the growth of supermassive black holes in galaxy centres is often assumed to be dominated by a smooth, steady flow of very hot plasma, but there is little direct evidence to support this idea. New observations of the Abell 2597 galaxy cluster provide evidence for an alternative model, cold accretion onto black holes, recently predicted by simulations and theory, but not directly observed. The data reveal cold, clumpy molecular clouds falling towards an active supermassive black hole in the nucleus of a nearby giant elliptical galaxy. Supermassive black holes in galaxy centres can grow by the accretion of gas, liberating energy that might regulate star formation on galaxy-wide scales1,2,3. The nature of the gaseous fuel reservoirs that power black hole growth is nevertheless largely unconstrained by observations, and is instead routinely simplified as a smooth, spherical inflow of very hot gas4. Recent theory5,6,7 and simulations8,9,10 instead predict that accretion can be dominated by a stochastic, clumpy distribution of very cold molecular clouds—a departure from the ‘hot mode’ accretion model—although unambiguous observational support for this prediction remains elusive. Here we report observations that reveal a cold, clumpy accretion flow towards a supermassive black hole fuel reservoir in the nucleus of the Abell 2597 Brightest Cluster Galaxy (BCG), a nearby (redshift z = 0.0821) giant elliptical galaxy surrounded by a dense halo of hot plasma11,12,13. Under the right conditions, thermal instabilities produce a rain of cold clouds that fall towards the galaxy’s centre14, sustaining star formation amid a kiloparsec-scale molecular nebula that is found at its core15. The observations show that these cold clouds also fuel black hole accretion, revealing ‘shadows’ cast by the molecular clouds as they move inward at about 300 kilometres per second towards the active supermassive black hole, which serves as a bright backlight. Corroborating evidence from prior observations16 of warmer atomic gas at extremely high spatial resolution17, along with simple arguments based on geometry and probability, indicate that these clouds are within the innermost hundred parsecs of the black hole, and falling closer towards it.

176 citations

Journal ArticleDOI
TL;DR: In this article, the authors detect 5 × 1010 M ☉ of molecular gas within 10 kpc of the A1835 brightest cluster galaxy (BCG) in the CO (3-2) and CO (1-0) emission lines.
Abstract: We report ALMA Early Science observations of the A1835 brightest cluster galaxy (BCG) in the CO (3-2) and CO (1-0) emission lines. We detect 5 × 1010 M ☉ of molecular gas within 10 kpc of the BCG. Its ensemble velocity profile width of ~130 km s–1 FWHM is too narrow for the molecular clouds to be supported in the galaxy by dynamic pressure. The gas may instead be supported in a rotating, turbulent disk oriented nearly face-on. Roughly 1010 M ☉ of molecular gas is projected 3-10 kpc to the northwest and to the east of the nucleus with line-of-sight velocities lying between –250 km s–1 and +480 km s–1 with respect to the systemic velocity. The high-velocity gas may be either inflowing or outflowing. However, the absence of high-velocity gas toward the nucleus that would be expected in a steady inflow, and its bipolar distribution on either side of the nucleus, are more naturally explained as outflow. Star formation and radiation from the active galactic nucleus (AGN) are both incapable of driving an outflow of this magnitude. The location of the high-velocity gas projected behind buoyantly rising X-ray cavities and favorable energetics suggest an outflow driven by the radio AGN. If so, the molecular outflow may be associated with a hot outflow on larger scales reported by Kirkpatrick and colleagues. The molecular gas flow rate of approximately 200 M ☉ yr–1 is comparable to the star formation rate of 100-180 M ☉ yr–1 in the central disk. How radio bubbles would lift dense molecular gas in their updrafts, how much gas will be lost to the BCG, and how much will return to fuel future star formation and AGN activity are poorly understood. Our results imply that radio-mechanical (radio-mode) feedback not only heats hot atmospheres surrounding elliptical galaxies and BCGs, but it is able to sweep higher density molecular gas away from their centers.

151 citations


Cited by
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Journal ArticleDOI
TL;DR: SciPy as discussed by the authors is an open source scientific computing library for the Python programming language, which includes functionality spanning clustering, Fourier transforms, integration, interpolation, file I/O, linear algebra, image processing, orthogonal distance regression, minimization algorithms, signal processing, sparse matrix handling, computational geometry, and statistics.
Abstract: SciPy is an open source scientific computing library for the Python programming language. SciPy 1.0 was released in late 2017, about 16 years after the original version 0.1 release. SciPy has become a de facto standard for leveraging scientific algorithms in the Python programming language, with more than 600 unique code contributors, thousands of dependent packages, over 100,000 dependent repositories, and millions of downloads per year. This includes usage of SciPy in almost half of all machine learning projects on GitHub, and usage by high profile projects including LIGO gravitational wave analysis and creation of the first-ever image of a black hole (M87). The library includes functionality spanning clustering, Fourier transforms, integration, interpolation, file I/O, linear algebra, image processing, orthogonal distance regression, minimization algorithms, signal processing, sparse matrix handling, computational geometry, and statistics. In this work, we provide an overview of the capabilities and development practices of the SciPy library and highlight some recent technical developments.

12,774 citations

Journal ArticleDOI
16 Sep 2020-Nature
TL;DR: In this paper, the authors review how a few fundamental array concepts lead to a simple and powerful programming paradigm for organizing, exploring and analysing scientific data, and their evolution into a flexible interoperability layer between increasingly specialized computational libraries is discussed.
Abstract: Array programming provides a powerful, compact and expressive syntax for accessing, manipulating and operating on data in vectors, matrices and higher-dimensional arrays. NumPy is the primary array programming library for the Python language. It has an essential role in research analysis pipelines in fields as diverse as physics, chemistry, astronomy, geoscience, biology, psychology, materials science, engineering, finance and economics. For example, in astronomy, NumPy was an important part of the software stack used in the discovery of gravitational waves1 and in the first imaging of a black hole2. Here we review how a few fundamental array concepts lead to a simple and powerful programming paradigm for organizing, exploring and analysing scientific data. NumPy is the foundation upon which the scientific Python ecosystem is constructed. It is so pervasive that several projects, targeting audiences with specialized needs, have developed their own NumPy-like interfaces and array objects. Owing to its central position in the ecosystem, NumPy increasingly acts as an interoperability layer between such array computation libraries and, together with its application programming interface (API), provides a flexible framework to support the next decade of scientific and industrial analysis. NumPy is the primary array programming library for Python; here its fundamental concepts are reviewed and its evolution into a flexible interoperability layer between increasingly specialized computational libraries is discussed.

7,624 citations

Journal ArticleDOI
TL;DR: SciPy as discussed by the authors is an open-source scientific computing library for the Python programming language, which has become a de facto standard for leveraging scientific algorithms in Python, with over 600 unique code contributors, thousands of dependent packages, over 100,000 dependent repositories and millions of downloads per year.
Abstract: SciPy is an open-source scientific computing library for the Python programming language. Since its initial release in 2001, SciPy has become a de facto standard for leveraging scientific algorithms in Python, with over 600 unique code contributors, thousands of dependent packages, over 100,000 dependent repositories and millions of downloads per year. In this work, we provide an overview of the capabilities and development practices of SciPy 1.0 and highlight some recent technical developments.

6,244 citations

Journal Article
TL;DR: The first direct detection of gravitational waves and the first observation of a binary black hole merger were reported in this paper, with a false alarm rate estimated to be less than 1 event per 203,000 years, equivalent to a significance greater than 5.1σ.
Abstract: On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0×10(-21). It matches the waveform predicted by general relativity for the inspiral and merger of a pair of black holes and the ringdown of the resulting single black hole. The signal was observed with a matched-filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203,000 years, equivalent to a significance greater than 5.1σ. The source lies at a luminosity distance of 410(-180)(+160) Mpc corresponding to a redshift z=0.09(-0.04)(+0.03). In the source frame, the initial black hole masses are 36(-4)(+5)M⊙ and 29(-4)(+4)M⊙, and the final black hole mass is 62(-4)(+4)M⊙, with 3.0(-0.5)(+0.5)M⊙c(2) radiated in gravitational waves. All uncertainties define 90% credible intervals. These observations demonstrate the existence of binary stellar-mass black hole systems. This is the first direct detection of gravitational waves and the first observation of a binary black hole merger.

4,375 citations

Journal ArticleDOI
TL;DR: In this article, it was shown that the radiative or quasar mode of feedback can account for the observed proportionality between the central black hole and the host galaxy mass, which can lead to ejection or heating of the gas.
Abstract: Radiation, winds, and jets from the active nucleus of a massive galaxy can interact with its interstellar medium, and this can lead to ejection or heating of the gas. This terminates star formation in the galaxy and stifles accretion onto the black hole. Such active galactic nuclei (AGN) feedback can account for the observed proportionality between the central black hole and the host galaxy mass. Direct observational evidence for the radiative or quasar mode of feedback, which occurs when AGN are very luminous, has been difficult to obtain but is accumulating from a few exceptional objects. Feedback from the kinetic or radio mode, which uses the mechanical energy of radio-emitting jets often seen when AGN are operating at a lower level, is common in massive elliptical galaxies. This mode is well observed directly through X-ray observations of the central galaxies of cool core clusters in the form of bubbles in the hot surrounding medium. The energy flow, which is roughly continuous, heats the hot intraclu...

2,299 citations