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Helmi, Prof. Amina

Amina Helmi (1970) is Professor of Dynamics, Structure and Formation of the Milky Way. Helmi wrote a groundbreaking PhD thesis (for which she was awarded the 2004 Christiaan Huygens Prize), shedding new light on the history and formation of the Milky Way by stating that it probably gradually merged with smaller galaxies. Helmi is searching for these separate galaxies (‘fossils’) and is thus a sort of astro-archaeologist, using the information from star fossils to reconstruct the formation of the Milky Way.

Helmi has been awarded a number of prestigious grants, including an NWO VIDI grant in 2003 and an ERC Starting Grant from the EU in 2009. She is an active member of numerous networks. In 2017 she has been elected as member of the KNAW, the Royal Netherlands Academy of Arts and Sciences. Helmi is closely involved with the GAIA telescope, launched in 2013, which is providing very precise measurements to chart the Milky Way. II 2014 a team of scientists, including Helmi, published the first map of the spatial distribution of the mysterious matter in the almost empty space between stars, in Science. In 2015 she was awarded a VICI grant for her research, and in 2017 an NWO grant. In 2018 she and her research group were one of the first to be given the opportunity to study a second set of data from Gaia missions. She discovered that the Milky Way swallowed a major star system 10 billion years ago.

In 2019 Helmi was awarded the Spinoza Prize, the highest academic award in the Netherlands. Besides the great honour, the winner of the Spinoza Prize receives a research budget of EUR 2.5 million.

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Publications

2021

Koppelman, H. H., Hagen, J. H. J., & Helmi, A. (2021). Frequencies, chaos, and resonances: A study of orbital parameters of nearby thick-disc and halo stars. Astronomy & astrophysics, 647(March 2021), [A37]. https://doi.org/10.1051/0004-6361/202039390
Reino, S., Rossi, E. M., Sanderson, R. E., Sellentin, E., Helmi, A., Koppelman, H. H., & Sharma, S. (2021). Galactic potential constraints from clustering in action space of combined stellar stream data. Monthly Notices of the Royal Astronomical Society, 502(3), 4170-4193. https://doi.org/10.1093/mnras/stab304
Koppelman, H. H., & Helmi, A. (2021). The reduced proper motion selected halo: Methods and description of the catalogue. Astronomy & astrophysics, 645(January 2021), [A69]. https://doi.org/10.1051/0004-6361/202038178
Skúladóttir, Á., Salvadori, S., Amarsi, A. M., Tolstoy, E., Irwin, M. J., Hill, V., Jablonka, P., Battaglia, G., Starkenburg, E., Massari, D., Helmi, A., & Posti, L. (2021). Zero-metallicity Hypernova Uncovered by an Ultra-metal-poor Star in the Sculptor Dwarf Spheroidal Galaxy. The Astrophysical Journal, 915(2), [L30]. https://doi.org/10.3847/2041-8213/ac0dc2

2020

Antoja, T., Ramos, P., Mateu, C., Helmi, A., Anders, F., Jordi, C., & Carballo-Bello, J. A. (2020). An all-sky proper-motion map of the Sagittarius stream using Gaia DR2. Astronomy & astrophysics, 635, [3]. https://doi.org/10.1051/0004-6361/201937145
Matsuno, T., Koppelman, H. H., & Helmi, A. (2020). Bright Stars from the Ancient Merger Gaia-Enceladus Visible with Binoculars. Research Notes of the AAS, 4(12), [246]. https://doi.org/10.3847/2515-5172/abd4d1
Gaia Collaboration (2020). Corrigendum: Gaia Data Release 2 Kinematics of globular clusters and dwarf galaxies around the Milky Way. Astronomy & astrophysics, 637, [3]. https://doi.org/10.1051/0004-6361/201832698e
Elias, L. M., Sales, L. V., Helmi, A., & Hernquist, L. (2020). Cosmological insights into the assembly of the radial and compact stellar halo of the Milky Way. Monthly Notices of the Royal Astronomical Society, 495(1), 29-39. https://doi.org/10.1093/mnras/staa1090
Ramos, P., Mateu, C., Antoja, T., Helmi, A., Castro-Ginard, A., Balbinot, E., & Carrasco, J. M. (2020). Full 5D characterisation of the Sagittarius stream with Gaia DR2 RR Lyrae. Astronomy & astrophysics, 638, [A104]. https://doi.org/10.1051/0004-6361/202037819
Ramos, P., Mateu, C., Antoja, T., Helmi, A., Castro-Ginard, A., Balbinot, E., & Carrasco, J. M. (2020). Full 5D characterisation of the Sagittarius stream with Gaia DR2 RR Lyrae (Corrigendum). Astronomy & astrophysics, 640, [C5]. https://doi.org/10.1051/0004-6361/202037819e
Gaia Collaboration, Helmi, A., Massari, D., Breddels, M. A., & Veljanoski, J. (2020). Gaia Data Release 2. The kinematics of globular clusters and dwarf galaxies around the Milky Way (Corrigendum). Astronomy & astrophysics, 642, [C1]. https://doi.org/10.1051/0004-6361/202039217
Massari, D., Helmi, A., Mucciarelli, A., Sales, L., Spina, L., & Tolstoy, E. (2020). Stellar 3D kinematics in the Draco dwarf spheroidal galaxy. Astronomy & astrophysics, 633, [36]. https://doi.org/10.1051/0004-6361/201935613
Helmi, A. (2020). Streams, Substructures, and the Early History of the Milky Way. Annual Review of Astronomy and Astrophysics, 58, 205-256. https://doi.org/10.1146/annurev-astro-032620-021917
Theler, R., Jablonka, P., Lucchesi, R., Lardo, C., North, P., Irwin, M., Battaglia, G., Hill, V., Tolstoy, E., Venn, K., Helmi, A., Kaufer, A., Primas, F., & Shetrone, M. (2020). The chemical evolution of the dwarf spheroidal galaxy Sextans. Astronomy & astrophysics, 642, [A176]. https://doi.org/10.1051/0004-6361/201937146
Ramos, P., Antoja, T., Mateu, C., Helmi, A., Castro-Ginard, A., Anders, F., Jordi, C., Carballo-Bello, J. A., Balbinot, E., & Carrasco, J. M. (2020). The Halo-Disc dynamical coupling: Gaia blind detection of the Monoceros and ACS structures. Paper presented at XIV.0 Scientific Meeting (virtual) of the Spanish Astronomical Society, held 13-15 July 2020, . https://ui.adsabs.harvard.edu/abs/2020sea..confE.177R
Koppelman, H. H., Bos, R. O. Y., & Helmi, A. (2020). The messy merger of a large satellite and a Milky Way-like galaxy. Astronomy & astrophysics, 642, [L18]. https://doi.org/10.1051/0004-6361/202038652
Antoja, T., Ramos, P., Mateu, C., Helmi, A., Castro-Ginard, A., Anders, F., Jordi, C., Carballo-Bello, J. A., Balbinot, E., & Carrasco, J. M. (2020). The Sagittarius stream with Gaia data. Paper presented at EA XIV.0 Reunión Científica , . https://ui.adsabs.harvard.edu/abs/2020sea..confE.117A
RAVE Collaboration (2020). The Sixth Data Release of the Radial Velocity Experiment (RAVE). I. Survey Description, Spectra, and Radial Velocities. The Astronomical Journal, 160(2), [82]. https://doi.org/10.3847/1538-3881/ab9ab9
RAVE Collaboration (2020). The Sixth Data Release of the Radial Velocity Experiment (Rave). II. Stellar Atmospheric Parameters, Chemical Abundances, and Distances. The Astronomical Journal, 160(2), [83]. https://doi.org/10.3847/1538-3881/ab9ab8

2019

Bignone, L. A., Helmi, A., & Tissera, P. B. (2019). A Gaia-Enceladus Analog in the EAGLE Simulation: Insights into the Early Evolution of the Milky Way. Astrophysical Journal Letters, 883(1), [5]. https://doi.org/10.3847/2041-8213/ab3e0e
Hagen, J. H. J., Helmi, A., & Breddels, M. A. (2019). Axisymmetric Schwarzschild models of an isothermal axisymmetric mock dwarf spheroidal galaxy. Astronomy & astrophysics, 632, [99]. https://doi.org/10.1051/0004-6361/201936196
Koppelman, H. H., Helmi, A., Massari, D., Roelenga, S., & Bastian, U. (2019). Characterization and history of the Helmi streams with Gaia DR2. Astronomy and astrophysics, 625, [A5]. https://doi.org/10.1051/0004-6361/201834769
Collaboration, G., Eyer, L., Rimoldini, L., Audard, M., Anderson, R. I., Nienartowicz, K., Glass, F., Marchal, O., Grenon, M., Mowlavi, N., Holl, B., Clementini, G., Aerts, C., Mazeh, T., Evans, D. W., Szabados, L., Brown, A. G. A., Vallenari, A., Prusti, T., ... Zwitter, T. (2019). Gaia Data Release 2. Variable stars in the colour-absolute magnitude diagram. Astronomy and astrophysics, 623, [A110]. https://doi.org/10.1051/0004-6361/201833304
Posti, L., & Helmi, A. (2019). Mass and shape of the Milky Way's dark matter halo with globular clusters from Gaia and Hubble. Astronomy & astrophysics, 621, [56]. https://doi.org/10.1051/0004-6361/201833355
Koppelman, H. H., Helmi, A., Massari, D., Price-Whelan, A. M., & Starkenburg, T. K. (2019). Multiple retrograde substructures in the Galactic halo: A shattered view of Galactic history. Astronomy & astrophysics, 631, [L9]. https://doi.org/10.1051/0004-6361/201936738
Massari, D., Koppelman, H. H., & Helmi, A. (2019). Origin of the system of globular clusters in the Milky Way. Astronomy & astrophysics, 630, [L4]. https://doi.org/10.1051/0004-6361/201936135
Sakari, C. M., Roederer, I. U., Placco, V. M., Beers, T. C., Ezzeddine, R., Frebel, A., Hansen, T., Sneden, C., Cowan, J. J., Wallerstein, G., Farrell, E. M., Venn, K. A., Matijevič, G., Wyse, R. F. G., Bland-Hawthorn, J., Chiappini, C., Freeman, K. C., Gibson, B. K., Grebel, E. K., ... Watson, F. (2019). The R-Process Alliance: Discovery of a Low-α, r-process-enhanced Metal-poor Star in the Galactic Halo. The Astrophysical Journal, 874(2), [148]. https://doi.org/10.3847/1538-4357/ab0c02
Hagen, J. H. J., Helmi, A., de Zeeuw, P. T., & Posti, L. (2019). The tilt of the velocity ellipsoid in the Milky Way with Gaia DR2. Astronomy & astrophysics, 629, 1-14. [A70]. https://doi.org/10.1051/0004-6361/201935264
Hill, V., Skúladóttir, Á., Tolstoy, E., Venn, K. A., Shetrone, M. D., Jablonka, P., Primas, F., Battaglia, G., de Boer, T. J. L., François, P., Helmi, A., Kaufer, A., Letarte, B., Starkenburg, E., & Spite, M. (2019). VLT/FLAMES high-resolution chemical abundances in Sculptor: a textbook dwarf spheroidal galaxy. Astronomy and astrophysics, 626, [A15]. https://doi.org/10.1051/0004-6361/201833950
4MOST, de Jong, R. S., Agertz, O., Agudo Berbel, A., Aird, J., Alexander, D. A., Amarsi, A., Anders, F., Andrae, R., Ansarinejad, B., Ansorge, W., Antilogus, P., Anwand-Heerwart, H., Arentsen, A., Arnadottir, A., Asplund, M., Auger, M., Azais, N., Baade, D., ... Kuijken, K. (2019). 4MOST: Project overview and information for the First Call for Proposals. ESO Messenger, 175. http://adsabs.harvard.edu/abs/2019arXiv190302464D
Helmi, A., Irwin, M., Deason, A., Balbinot, E., Belokurov, V., Bland-Hawthorn, J., Christlieb, N., Cioni, M. -R. L., Feltzing, S., Grebel, E. K., Kordopatis, G., Starkenburg, E., Walton, N., & Worley, C. C. (2019). 4MOST Consortium Survey 1: The Milky Way Halo Low-Resolution Survey. The Messenger, 175, 23-25. https://doi.org/10.18727/0722-6691/5120
Christlieb, N., Battistini, C., Bonifacio, P., Caffau, E., Ludwig, H. -G., Asplund, M., Barklem, P., Bergemann, M., Church, R., Feltzing, S., Ford, D., Grebel, E. K., Hansen, C. J., Helmi, A., Kordopatis, G., Kovalev, M., Korn, A., Lind, K., Quirrenbach, A., ... Starkenburg, E. (2019). 4MOST Consortium Survey 2: The Milky Way Halo High-Resolution Survey. The Messenger, 175, 26-29. https://doi.org/10.18727/0722-6691/5121

2018

Antoja, T., Helmi, A., Romero-Gómez, M., Katz, D., Babusiaux, C., Drimmel, R., Evans, D. W., Figueras, F., Poggio, E., Reylé, C., Robin, A. C., Seabroke, G., & Soubiran, C. (2018). A dynamically young and perturbed Milky Way disk. Nature, 561(7723), 360-362. https://doi.org/10.1038/s41586-018-0510-7
Letarte, B., Hill, V., Tolstoy, E., Jablonka, P., Shetrone, M., Venn, K. A., Spite, M., Irwin, M. J., Battaglia, G., Helmi, A., Primas, F., François, P., Kaufer, A., Szeifert, T., Arimoto, N., & Sadakane, K. (2018). Corrigendum: A high-resolution VLT/FLAMES study of individual stars in the centre of the Fornax dwarf spheroidal galaxy. Astronomy and astrophysics, 613, C1. https://doi.org/10.1051/0004-6361/200913413e
Gaia Collaboration (2018). Gaia Data Release 2: Kinematics of globular clusters and dwarf galaxies around the Milky Way. Astronomy & astrophysics, 616, A12. [12]. https://doi.org/10.1051/0004-6361/201832698
Gaia Collaboration (2018). Gaia Data Release 2: Observational Hertzsprung-Russell diagrams. Unpublished. https://doi.org/10.1051/0004-6361/201832843
Arenou, F., Luri, X., Babusiaux, C., Fabricius, C., Helmi, A., Muraveva, T., Robin, A. C., Spoto, F., Vallenari, A., Antoja, T., Cantat-Gaudin, T., Jordi, C., Leclerc, N., Reyle, C., Romero-Gomez, M., Shih, I. -C., Soria, S., Barache, C., Bossini, D., ... Zurbach, C. (2018). Gaia Data Release 2: Catalogue validation. Unpublished. https://doi.org/10.1051/0004-6361/201833234
Gaia Collaboration (2018). Gaia Data Release 2: The celestial reference frame (Gaia-CRF2). Astronomy and astrophysics, 616, [A14]. https://doi.org/10.1051/0004-6361/201832916
Gaia Collaboration (2018). Gaia Data Release 2: Observations of solar system objects. Astronomy & astrophysics, 616, [13]. https://doi.org/10.1051/0004-6361/201832900
Gaia Collaboration (2018). Gaia Data Release 2: Mapping the Milky Way disc kinematics. Astronomy & astrophysics, 616, [11]. https://doi.org/10.1051/0004-6361/201832865
Gaia Collaboration (2018). Gaia Data Release 2: Summary of the contents and survey properties. Astronomy & astrophysics, 616, [1]. https://doi.org/10.1051/0004-6361/201833051
McMillan, P. J., Kordopatis, G., Kunder, A., Binney, J., Wojno, J., Zwitter, T., Steinmetz, M., Bland-Hawthorn, J., Gibson, B. K., Gilmore, G., Grebel, E. K., Helmi, A., Munari, U., Navarro, J. F., Parker, Q. A., Seabroke, G., Watson, F., & Wyse, R. F. G. (2018). Improved distances and ages for stars common to TGAS and RAVE. Monthly Notices of the Royal Astronomical Society, 477(4), 5279-5300. https://doi.org/10.1093/mnras/sty990
Carrillo, I., Minchev, I., Kordopatis, G., Steinmetz, M., Binney, J., Anders, F., Bienaymé, O., Bland-Hawthorn, J., Famaey, B., Freeman, K. C., Gilmore, G., Gibson, B. K., Grebel, E. K., Helmi, A., Just, A., Kunder, A., McMillan, P., Monari, G., Munari, U., ... Zwitter, T. (2018). Is the Milky Way still breathing? RAVE-Gaia streaming motions. Monthly Notices of the Royal Astronomical Society, 475(2), 2679-2696. https://doi.org/10.1093/mnras/stx3342
Koppelman, H., Helmi, A., & Veljanoski, J. (2018). One Large Blob and Many Streams Frosting the nearby Stellar Halo in Gaia~DR2. Astrophysical Journal Letters, 860(1), L11. https://doi.org/10.3847/2041-8213/aac882
Posti, L., Helmi, A., Veljanoski, J., & Breddels, M. A. (2018). The dynamically selected stellar halo of the Galaxy with Gaia and the tilt of the velocity ellipsoid. Astronomy and astrophysics, 615, A70. https://doi.org/10.1051/0004-6361/201732277
Hagen, J. H. J., & Helmi, A. (2018). The kinematics and surface mass density in the solar neighbourhood using TGASxRAVE. In A. Recio-Blanco, P. de Laverny, A. G. A. Brown, & T. Prusti (Eds.), Proceedings of the International Astronomical Unian: Astrometry and astrophysics in the Gaia sky (Vol. 12, pp. 160-163). Cambridge University Press. https://doi.org/10.1017/S1743921317005725
Helmi, A., Babusiaux, C., Koppelman, H. H., Massari, D., Veljanoski, J., & Brown, A. G. A. (2018). The merger that led to the formation of the Milky Way’s inner stellar halo and thick disk. Nature, 563(7729), 85-88. https://doi.org/10.1038/s41586-018-0625-x
Sakari, C. M., Placco, V. M., Farrell, E. M., Roederer, I. U., Wallerstein, G., Beers, T. C., Ezzeddine, R., Frebel, A., Hansen, T., Holmbeck, E. M., Sneden, C., Cowan, J. J., Venn, K. A., Davis, C. E., Matijevic, G., Wyse, R. F. G., Bland-Hawthorn, J., Chiappini, C., Freeman, K. C., ... Watson, F. (2018). The R-Process Alliance: First Release from the Northern Search for r-process-enhanced Metal-poor Stars in the Galactic Halo. The Astrophysical Journal, 868(2), [110]. https://doi.org/10.3847/1538-4357/aae9df
Hagen, J. H. J., & Helmi, A. (2018). The surface mass density in the solar neighbourhood using red clumps stars in TGASxRAVE. In C. Chiappini, I. Minchev, E. Starkenburg, & M. Valentini (Eds.), Rediscovering Our Galaxy (pp. 304-305). (Proceedings of the International Astronomical Union Symposia and Colloquia; Vol. S334). Cambridge University Press. https://doi.org/10.1017/S1743921317006524
Koppelman, H. H., & Helmi, A. (2018). The time evolution of gaps in tidal streams in axisymmetric potentials. In A. Recio-Blanco, P. de Laverny, A. G. A. Brown, & T. Prusti (Eds.), Proceedings of the International Astronomical Union: Astrometry and Astrophysics in the Gaia sky (Vol. 12, pp. 229-230). Cambridge University Press. https://doi.org/10.1017/S1743921317006135
Hagen, J. H. J., & Helmi, A. (2018). The vertical force in the solar neighbourhood using red clump stars in TGAS and RAVE: Constraints on the local dark matter density. Astronomy and astrophysics, 615, [A99]. https://doi.org/10.1051/0004-6361/201832903
Massari, D., Breddels, M. A., Helmi, A., Posti, L., Brown, A. G. A., & Tolstoy, E. (2018). Three-dimensional motions in the Sculptor dwarf galaxy as a glimpse of a new era. Nature Astronomy, 2(2), 156-161. [A70]. https://doi.org/10.1038/s41550-017-0322-y
Koppelman, H. H., & Helmi, A. (2018). Time evolution of the properties of gaps in stellar streams in axisymmetric potentials. In C. Chiappini, I. Minchev, E. Starkenburg, & M. Valentini (Eds.), Rediscovering Our Galaxy (pp. 321-322). (Proceedings of the International Astronomical Union Symposia and Colloquia; Vol. S334). Cambridge University Press. https://doi.org/10.1017/S1743921317006901
Veljanoski, J., Posti, L., Helmi, A., & Breddels, M. A. (2018). Unveiling the stellar halo with TGAS. In A. Recio-Blanco, P. de Laverny, A. G. A. Brown, & T. Prusti (Eds.), Proceedings of the International Astronomical Union: Astrometry and Astrophysics in the Gaia sky (Vol. 12, pp. 275-276). Cambridge University Press. https://doi.org/10.1017/S1743921317007141
Massari, D., & Helmi, A. (2018). With and without spectroscopy: Gaia DR2 proper motions of seven Ultra- Faint Dwarf Galaxies. Astronomy & astrophysics, 620, [A155]. https://doi.org/10.1051/0004-6361/201833367

2017

Helmi, A., Veljanoski, J., Breddels, M. A., Tian, H., & Sales, L. V. (2017). A box full of chocolates: The rich structure of the nearby stellar halo revealed by Gaia and RAVE. Astronomy and astrophysics, 598, [A58]. https://doi.org/10.1051/0004-6361/201629990
Antoja, T., Kordopatis, G., Helmi, A., Monari, G., Famaey, B., Wyse, R. F. G., Grebel, E. K., Steinmetz, M., Bland-Hawthorn, J., Gibson, B. K., Bienaymé, O., Navarro, J. F., Parker, Q. A., Reid, W., Seabroke, G., Siebert, A., Siviero, A., & Zwitter, T. (2017). Asymmetric metallicity patterns in the stellar velocity space with RAVE. Astronomy & astrophysics, 601, [A59]. https://doi.org/10.1051/0004-6361/201629387
Buist, H. J. T., & Helmi, A. (2017). Behaviour of streams in angle and frequency spaces in different potentials. Astronomy & astrophysics, 601, [37]. https://doi.org/10.1051/0004-6361/201527930
van Oirschot, P., Starkenburg, E., Helmi, A., & Nelemans, G. (2017). Building blocks of the Milky Way's accreted spheroid. Monthly Notices of the Royal Astronomical Society, 464(1), 863-875. https://doi.org/10.1093/mnras/stw2340
Arenou, F., Luri, X., Babusiaux, C., Fabricius, C., Helmi, A., Robin, A. C., Vallenari, A., Blanco-Cuaresma, S., Cantat-Gaudin, T., Findeisen, K., Reylé, C., Ruiz-Dern, L., Sordo, R., Turon, C., Walton, N. A., Shih, I-C., Antiche, E., Barache, C., Barros, M., ... Bragaglia, A. (2017). Gaia Data Release 1: Catalogue validation. Astronomy & astrophysics, 599, [A50]. https://doi.org/10.1051/0004-6361/201629895, https://doi.org/10.1051/0004-6361/201629895
Gaia Collaboration (2017). Gaia Data Release 1. Open cluster astrometry: performance, limitations, and future prospects. Astronomy & astrophysics, 601, [A19]. https://doi.org/10.1051/0004-6361/201730552
Gaia Collaboration, U., Clementini, G., Eyer, L., Ripepi, V., Marconi, M., Muraveva, T., Garofalo, A., Sarro, L. M., Palmer, M., Luri, X., Molinaro, R., Rimoldini, L., Szabados, L., Musella, I., Anderson, R. I., Prusti, T., de Bruijne, J. H. J., Brown, A. G. A., Vallenari, A., ... Zschocke, S. (2017). Gaia Data Release 1. Testing parallaxes with local Cepheids and RR Lyrae stars. Astronomy & astrophysics, 605, A79. https://doi.org/10.1051/0004-6361/201629925
Sanderson, R. E., Hartke, J., & Helmi, A. (2017). Modeling the Gravitational Potential of a Cosmological Dark Matter Halo with Stellar Streams. The Astrophysical Journal, 836(2), [234]. https://doi.org/10.3847/1538-4357/aa5eb4
Valentini, M., Chiappini, C., Davies, G. R., Elsworth, Y. P., Mosser, B., Lund, M. N., Miglio, A., Chaplin, W. J., Rodrigues, T. S., Boeche, C., Steinmetz, M., Matijevič, G., Kordopatis, G., Bland-Hawthorn, J., Munari, U., Bienaymé, O., Freeman, K. C., Gibson, B. K., Gilmore, G., ... Mott, A. (2017). RAVE stars in K2. I. Improving RAVE red giants spectroscopy using asteroseismology from K2 Campaign 1. Astronomy & astrophysics, 600, [A66]. https://doi.org/10.1051/0004-6361/201629701
Massari, D., Posti, L., Helmi, A., Fiorentino, G., & Tolstoy, E. (2017). The power of teaming up HST and Gaia: The first proper motion measurement of the distant cluster NGC 2419. Astronomy and astrophysics, 598, [L9]. https://doi.org/10.1051/0004-6361/201630174
Kunder, A., Kordopatis, G., Steinmetz, M., Zwitter, T., McMillan, P. J., Casagrande, L., Enke, H., Wojno, J., Valentini, M., Chiappini, C., Matijevič, G., Siviero, A., de Laverny, P., Recio-Blanco, A., Bijaoui, A., Wyse, R. F. G., Binney, J., Grebel, E. K., Helmi, A., ... Mosser, B. (2017). The Radial Velocity Experiment (RAVE): Fifth Data Release. The Astronomical Journal, 153(2), 75. https://doi.org/10.3847/1538-3881/153/2/75
Casey, A. R., Hawkins, K., Hogg, D. W., Ness, M., Rix, H-W., Kordopatis, G., Kunder, A., Steinmetz, M., Koposov, S., Enke, H., Sanders, J., Gilmore, G., Zwitter, T., Freeman, K. C., Casagrande, L., Matijevič, G., Seabroke, G., Bienaymé, O., Bland-Hawthorn, J., ... Wyse, R. (2017). The RAVE-on Catalog of Stellar Atmospheric Parameters and Chemical Abundances for Chemo-dynamic Studies in the Gaia Era. The Astrophysical Journal, 840(1), [59]. https://doi.org/10.3847/1538-4357/aa69c2
Wojno, J., Kordopatis, G., Piffl, T., Binney, J., Steinmetz, M., Matijevič, G., Bland-Hawthorn, J., Sharma, S., McMillan, P., Watson, F., Reid, W., Kunder, A., Enke, H., Grebel, E. K., Seabroke, G., Wyse, R. F. G., Zwitter, T., Bienaymé, O., Freeman, K. C., ... Siebert, A. (2017). The selection function of the RAVE survey. Monthly Notices of the Royal Astronomical Society, 468(3), 3368-3380. https://doi.org/10.1093/mnras/stx606
Matijevič, G., Chiappini, C., Grebel, E. K., Wyse, R. F. G., Zwitter, T., Bienaymé, O., Bland-Hawthorn, J., Freeman, K. C., Gibson, B. K., Gilmore, G., Helmi, A., Kordopatis, G., Kunder, A., Munari, U., Navarro, J. F., Parker, Q. A., Reid, W., Seabroke, G., Siviero, A., ... Watson, F. (2017). Very metal-poor stars observed by the RAVE survey. Astronomy & astrophysics, 603, [A19]. https://doi.org/10.1051/0004-6361/201730417
van Oirschot, P., Nelemans, G., Starkenburg, E., Toonen, S., Helmi, A., & Zwart, S. P. (2017). White dwarfs in the building blocks of the Galactic spheroid. Astronomy & astrophysics, 607, [A99]. https://doi.org/10.1051/0004-6361/201730418

2016

Buist, H. J. T., & Helmi, A. (2016). Corrigendum: A new fitting-function to describe the time evolution of a galaxy's gravitational potential ( Mar-2014 In : Astronomy & Astrophysics. 563, p. A110 5 p.). Astronomy and astrophysics, 589, [C3]. https://doi.org/10.1051/0004-6361/201323059e
Starkenburg, T. K., Helmi, A., & Sales, L. V. (2016). Dark influences II. Gas and star formation in minor mergers of dwarf galaxies with dark satellites. Astronomy and astrophysics, 587(March 2016), [A24]. https://doi.org/10.1051/0004-6361/201527247
Starkenburg, T. K., Helmi, A., & Sales, L. V. (2016). Dark influences. III. Structural characterization of minor mergers of dwarf galaxies with dark satellites. Astronomy and astrophysics, 595( November 2016 ), [A56]. https://doi.org/10.1051/0004-6361/201528066
Collaboration, G., Brown, A. G. A., Vallenari, A., Prusti, T., de Bruijne, J. H. J., Mignard, F., Drimmel, R., Babusiaux, C., Bailer-Jones, C. A. L., Bastian, U., Biermann, M., Evans, D. W., Eyer, L., Jansen, F., Jordi, C., Katz, D., Klioner, S. A., Lammers, U., Lindegren, L., ... Zschocke, S. (2016). Gaia Data Release 1. Summary of the astrometric, photometric, and survey properties. Astronomy & astrophysics, 595, [A2]. https://doi.org/10.1051/0004-6361/201629512
Helmi, A., Bragaglia, A., Arnaboldi, M., Rejkuba, M., & Romano, D. (2016). Stellar halos and the link to galaxy formation. In Proceedings of the International Astronomical Union (S317 ed., Vol. 11, pp. 228-234). IAU. https://doi.org/10.1017/S1743921315009771
Collaboration, G., Prusti, T., de Bruijne, J. H. J., Brown, A. G. A., Vallenari, A., Babusiaux, C., Bailer-Jones, C. A. L., Bastian, U., Biermann, M., Evans, D. W., Eyer, L., Jansen, F., Jordi, C., Klioner, S. A., Lammers, U., Lindegren, L., Luri, X., Mignard, F., Milligan, D. J., ... Zschocke, S. (2016). The Gaia mission. Astronomy and astrophysics, 595(November), [A1]. https://doi.org/10.1051/0004-6361/201629272
Veljanoski, J., & Helmi, A. (2016). The kinematics of globular clusters systems in the outer halos of the Aquarius simulations. Astronomy & astrophysics, 592(August 2016), [A55]. https://doi.org/10.1051/0004-6361/201628292
Yaryura, C. Y., Helmi, A., Abadi, M. G., & Starkenburg, E. (2016). The low-mass end of the neutral gas mass and velocity width functions of galaxies in ΛCDM. Monthly Notices of the Royal Astronomical Society, 457, 2415-2422. https://doi.org/10.1093/mnras/stw139
Helmi, A., & Koppelman, H. H. (2016). The Time Evolution of Gaps in Tidal Streams. Astrophysical Journal Letters, 828(1). https://doi.org/10.3847/2041-8205/828/1/L10
de Jong, R. S., Barden, S. C., Bellido-Tirado, O., Brynnel, J. G., Frey, S., Giannone, D., Haynes, R., Johl, D., Phillips, D., Schnurr, O., Walcher, J. C., Winkler, R., Ansorge, W. R., Feltzing, S., McMahon, R. G., Baker, G., Caillier, P., Dwelly, T., Gaessler, W., ... Starkenburg, E. (2016). 4MOST: the 4-metre Multi-Object Spectroscopic Telescope project at preliminary design review. In Proc. SPIE 9908, Ground-based and Airborne Instrumentation for Astronomy VI, 99081O (August 9, 2016) (Vol. 9908). [99081O] SPIE. https://doi.org/10.1117/12.2232832

2015

E. Sanderson, R., Helmi, A., & W. Hogg, D. (2015). Action-space Clustering of Tidal Streams to Infer the Galactic Potential. The Astrophysical Journal, 801(2), 98-115. https://doi.org/10.1088/0004-637X/801/2/98
van Oirschot, P., Starkenburg, E., Helmi, A., & Nelemans, G. (2015). Building blocks of the Milky Way's stellar halo. IAU General Assembly , 22, 2256918.
Hawkins, K., Kordopatis, G., Gilmore, G., Masseron, T., Wyse, R. F. G., Ruchti, G., Bienaymé, O., Bland-Hawthorn, J., Boeche, C., Freeman, K., Gibson, B. K., Grebel, E. K., Helmi, A., Kunder, A., Munari, U., Navarro, J. F., Parker, Q. A., Reid, W. A., Scholz, R. D., ... Zwitter, T. (2015). Characterizing the high-velocity stars of RAVE: the discovery of a metal-rich halo star born in the Galactic disc. Monthly Notices of the Royal Astronomical Society, 447(2), 2046-2058. https://doi.org/10.1093/mnras/stu2574
Starkenburg, T. K., & Helmi, A. (2015). Dark influences: imprints of dark satellites on dwarf galaxies. Astronomy and astrophysics, 575(A59), [A59]. https://doi.org/10.1051/0004-6361/201425082
Antoja, T., Figueras, F., Helmi, A., Monari, G., & RAVE Collaboration, U. (2015). Dynamical processes in the disk of the Milky Way and Gaia perspective. In Highlights of Spanish Astrophysics VIII, Proceedings of the XI Scientific Meeting of the Spanish Astronomical Society held on September 8-12, 2014, in Teruel, Spain, ISBN 978-84-606-8760-3. A. J. Cenarro, F. Figueras, C. Hernández-Monteagudo, J. Trujillo Bueno, and L. Valdivielso (eds.), p. 384-389 (pp. 384-389)
De Lucia, G., Tornatore, L., Frenk, C. S., Helmi, A., Navarro, J. F., & White, S. D. M. (2015). Erratum: elemental abundances in Milky Way-like galaxies from a hierarchical galaxy formation model. Monthly Notices of the Royal Astronomical Society, 447(4), 3420-3421. https://doi.org/10.1093/mnras/stu2609
Helmi, A. (2015). Galactic dynamics in the era of Gaia. IAU General Assembly , 22, 2257323.
Sanderson, R. E., Hartke, J., Helmi, A., & Hogg, D. W. (2015). Inferring the Galactic gravitational potential with Gaia and friends. Bulletin of the American Astronomical Society, 47(2), 36-36. http://adsabs.harvard.edu/abs/2015AAS...22511902S
Helmi, A., & Sanderson, R. E. (2015). Mass modelling from stellar streams in the Milky Way. In Galaxy Masses as Constraints of Formation Models : Proceedings of the International Astronomical Union, IAU Symposium (Vol. 311, pp. 11-15). International Astronomical Union. https://doi.org/10.1017/S1743921315003300
Breddels, M. A., Vera-Ciro, C., & Helmi, A. (2015). Matching the Dark Matter Profiles of dSph Galaxies with Those of Simulated Satellites: A Two-parameter Comparison. The Astrophysical Journal, 814(2), L23-L27. https://doi.org/10.1088/2041-8205/814/2/L23
Helmi, A. (2015). The connection between galaxy formation and the assembly of stellar halos in the Local Group. IAU General Assembly , 22, 2255632.
Jablonka, P., North, P., Mashonkina, L., Hill, V., Revaz, Y., Shetrone, M., Starkenburg, E., Irwin, M., Tolstoy, E., Battaglia, G., Venn, K., Helmi, A., Primas, F., & François, P. (2015). The early days of the Sculptor dwarf spheroidal galaxy. Astronomy and astrophysics, 583, [A67]. https://doi.org/10.1051/0004-6361/201525661
Buist, H. J. T., & Helmi, A. (2015). The evolution of streams in a time-dependent potential. Astronomy & astrophysics, 584, [A120]. https://doi.org/10.1051/0004-6361/201526203
Antoja , T., Monari, G., Helmi, A., Bienaymé, O., Bland-Hawthorn, J., Famaey, B., Gibson, B. K., Grebel, E. K., Kordopatis, G., Munari, U., Navarro, J., Parker, Q., Reid, W. A., Seabroke, G., Steinmetz, M., & Zwitter, T. (2015). The Imprints of the Galactic Bar on the Thick Disk with Rave. Astrophysical Journal Letters, 800(2), [32]. https://doi.org/10.1088/2041-8205/800/2/L32
Kordopatis, G., Binney, J., Gilmore, G., Wyse, R. F. G., Belokurov, V., McMillan, P. J., Hatfield, P., Grebel, E. K., Steinmetz, M., Navarro, J. F., Seabroke, G., Minchev, I., Chiappini, C., Bienaymé, O., Bland-Hawthorn, J., Freeman, K. C., Gibson, B. K., Helmi, A., Munari, U., ... Zwitter, T. (2015). The rich are different: evidence from the RAVE survey for stellar radial migration. Monthly Notices of the Royal Astronomical Society, 447(4), 3526-3535. https://doi.org/10.1093/mnras/stu2726

2014

Buist, H. J. T., & Helmi, A. (2014). A new fitting-function to describe the time evolution of a galaxy's gravitational potential. Astronomy & astrophysics, 563, [A110]. https://doi.org/10.1051/0004-6361/201323059
Minchev, I., Chiappini, C., Martig, M., Steinmetz, M., de Jong, R. S., Boeche, C., Scannapieco, C., Zwitter, T., Wyse, R. F. G., Binney, J. J., Bland-Hawthorn, J., Bienaymé, O., Famaey, B., Freeman, K. C., Gibson, B. K., Grebel, E. K., Gilmore, G., Helmi, A., Kordopatis, G., ... Williams, M. (2014). A New Stellar Chemo-Kinematic Relation Reveals the Merger History of the Milky Way Disk. The Astrophysical Journal, 781(1), L20-L25. https://doi.org/10.1088/2041-8205/781/1/L20
Sanderson, R., Helmi, A., & Hogg, D. W. (2014). Action-space clustering of tidal streams to infer the Galactic potential. In American Astronomical Society Meeting Abstracts (pp. 346.10)
Sanderson, R. E., Helmi, A., & Hogg, D. W. (2014). Action-space clustering of tidal streams to map the Galactic potential. In Setting the scene for Gaia and LAMOST (pp. 207-212). (Proceedings of the International Astronomical Union; Vol. 9, No. S298). Cambridge University Press. https://doi.org/10.1017/S1743921313006388
Munari, U., Henden, A., Frigo, A., Zwitter, T., Bienaymé, O., Bland-Hawthorn, J., Boeche, C., Freeman, K. C., Gibson, B. K., Gilmore, G., Grebel, E. K., Helmi, A., Kordopatis, G., Levine, S. E., Navarro, J. F., Parker, Q. A., Reid, W., Seabroke, G. M., Siebert, A., ... Wyse, R. F. G. (2014). APASS Landolt-Sloan BVgri Photometry of RAVE Stars. I. Data, Effective Temperatures, and Reddenings. The Astronomical Journal, 148(5), 81-95. https://doi.org/10.1088/0004-6256/148/5/81
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