1
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Pietrzyński G, Graczyk D, Gallenne A, Gieren W, Thompson IB, Pilecki B, Karczmarek P, Górski M, Suchomska K, Taormina M, Zgirski B, Wielgórski P, Kołaczkowski Z, Konorski P, Villanova S, Nardetto N, Kervella P, Bresolin F, Kudritzki RP, Storm J, Smolec R, Narloch W. A distance to the Large Magellanic Cloud that is precise to one per cent. Nature 2019; 567:200-203. [PMID: 30867610 DOI: 10.1038/s41586-019-0999-4] [Citation(s) in RCA: 225] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 01/02/2019] [Indexed: 11/09/2022]
Abstract
In the era of precision cosmology, it is essential to determine the Hubble constant empirically with an accuracy of one per cent or better1. At present, the uncertainty on this constant is dominated by the uncertainty in the calibration of the Cepheid period-luminosity relationship2,3 (also known as the Leavitt law). The Large Magellanic Cloud has traditionally served as the best galaxy with which to calibrate Cepheid period-luminosity relations, and as a result has become the best anchor point for the cosmic distance scale4,5. Eclipsing binary systems composed of late-type stars offer the most precise and accurate way to measure the distance to the Large Magellanic Cloud. Currently the limit of the precision attainable with this technique is about two per cent, and is set by the precision of the existing calibrations of the surface brightness-colour relation5,6. Here we report a calibration of the surface brightness-colour relation with a precision of 0.8 per cent. We use this calibration to determine a geometrical distance to the Large Magellanic Cloud that is precise to 1 per cent based on 20 eclipsing binary systems. The final distance is 49.59 ± 0.09 (statistical) ± 0.54 (systematic) kiloparsecs.
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Affiliation(s)
- G Pietrzyński
- Nicolaus Copernicus Astronomical Centre, Warsaw, Poland. .,Universidad de Concepción, Departamento de Astronomìa, Concepciòn, Chile.
| | - D Graczyk
- Nicolaus Copernicus Astronomical Centre, Warsaw, Poland.,Universidad de Concepción, Departamento de Astronomìa, Concepciòn, Chile.,Millennium Institute of Astrophysics (MAS), Santiago, Chile
| | - A Gallenne
- European Southern Observatory, Santiago, Chile.,Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS, Laboratoire Lagrange, Nice, France
| | - W Gieren
- Universidad de Concepción, Departamento de Astronomìa, Concepciòn, Chile
| | | | - B Pilecki
- Nicolaus Copernicus Astronomical Centre, Warsaw, Poland
| | | | - M Górski
- Universidad de Concepción, Departamento de Astronomìa, Concepciòn, Chile
| | - K Suchomska
- Warsaw University Observatory, Warsaw, Poland
| | - M Taormina
- Nicolaus Copernicus Astronomical Centre, Warsaw, Poland
| | - B Zgirski
- Nicolaus Copernicus Astronomical Centre, Warsaw, Poland
| | - P Wielgórski
- Nicolaus Copernicus Astronomical Centre, Warsaw, Poland
| | - Z Kołaczkowski
- Nicolaus Copernicus Astronomical Centre, Warsaw, Poland.,Astronomical Institute, Wrocław University, Wrocław, Poland
| | - P Konorski
- Warsaw University Observatory, Warsaw, Poland
| | - S Villanova
- Universidad de Concepción, Departamento de Astronomìa, Concepciòn, Chile
| | - N Nardetto
- Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS, Laboratoire Lagrange, Nice, France
| | - P Kervella
- LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Paris Diderot, Sorbonne Paris Cité, Meudon, France
| | - F Bresolin
- Institute for Astronomy, Honolulu, HI, USA
| | - R P Kudritzki
- Institute for Astronomy, Honolulu, HI, USA.,Munich University Observatory, Munich, Germany
| | - J Storm
- Leibniz Institute for Astrophysics, Potsdam, Germany
| | - R Smolec
- Nicolaus Copernicus Astronomical Centre, Warsaw, Poland
| | - W Narloch
- Nicolaus Copernicus Astronomical Centre, Warsaw, Poland
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2
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Shvartzvald Y, Maoz D, Udalski A, Sumi T, Friedmann M, Kaspi S, Poleski R, Szymański MK, Skowron J, Kozłowski S, Wyrzykowski L, Mróz P, Pietrukowicz P, Pietrzyński G, Soszyński I, Ulaczyk K, Abe F, Barry RK, Bennett DP, Bhattacharya A, Bond I, Freeman M, Inayama K, Itow Y, Koshimoto N, Ling C, Masuda K, Fukui A, Matsubara Y, Muraki Y, Ohnishi K, Rattenbury NJ, Saito T, Sullivan D, Suzuki D, Tristram PJ, Wakiyama Y, Yonehara A. The frequency of snowline-region planets from four-years of OGLE-MOA-Wise second-generation microlensing. Mon Not R Astron Soc 2016; 457:4089-4113. [PMID: 32848283 PMCID: PMC7447140 DOI: 10.1093/mnras/stw191] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We present a statistical analysis of the first four seasons from a "second-generation" microlensing survey for extrasolar planets, consisting of near-continuous time coverage of 8 deg2 of the Galactic bulge by the OGLE, MOA, and Wise microlensing surveys. During this period, 224 microlensing events were observed by all three groups. Over 12% of the events showed a deviation from single-lens microlensing, and for ~1/3 of those the anomaly is likely caused by a planetary companion. For each of the 224 events we have performed numerical ray-tracing simulations to calculate the detection efficiency of possible companions as a function of companion-to-host mass ratio and separation. Accounting for the detection efficiency, we find that 55 - 22 + 34 % of microlensed stars host a snowline planet. Moreover, we find that Neptunes-mass planets are ~ 10 times more common than Jupiter-mass planets. The companion-to-host mass ratio distribution shows a deficit at q ~ 10-2, separating the distribution into two companion populations, analogous to the stellar-companion and planet populations, seen in radial-velocity surveys around solar-like stars. Our survey, however, which probes mainly lower-mass stars, suggests a minimum in the distribution in the super-Jupiter mass range, and a relatively high occurrence of brown-dwarf companions.
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Affiliation(s)
- Y. Shvartzvald
- School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978, Israel
- The Wise Observatory Group
| | - D. Maoz
- School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978, Israel
- The Wise Observatory Group
| | - A. Udalski
- Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland
- Optical Gravitational Lens Experiment (OGLE) Collaboration
| | - T. Sumi
- Department of Earth and Space Science, Osaka University, Osaka 560-0043, Japan
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - M. Friedmann
- School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978, Israel
- The Wise Observatory Group
| | - S. Kaspi
- School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978, Israel
- The Wise Observatory Group
| | - R. Poleski
- Department of Astronomy, Ohio State University, 140 W. 18th Ave., Columbus, OH 43210, USA
- Optical Gravitational Lens Experiment (OGLE) Collaboration
| | - M. K. Szymański
- Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland
- Optical Gravitational Lens Experiment (OGLE) Collaboration
| | - J. Skowron
- Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland
- Optical Gravitational Lens Experiment (OGLE) Collaboration
| | - S. Kozłowski
- Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland
- Optical Gravitational Lens Experiment (OGLE) Collaboration
| | - L. Wyrzykowski
- Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland
- Optical Gravitational Lens Experiment (OGLE) Collaboration
| | - P. Mróz
- Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland
- Optical Gravitational Lens Experiment (OGLE) Collaboration
| | - P. Pietrukowicz
- Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland
- Optical Gravitational Lens Experiment (OGLE) Collaboration
| | - G. Pietrzyński
- Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland
- Optical Gravitational Lens Experiment (OGLE) Collaboration
| | - I. Soszyński
- Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland
- Optical Gravitational Lens Experiment (OGLE) Collaboration
| | - K. Ulaczyk
- Department of Physics, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK
- Optical Gravitational Lens Experiment (OGLE) Collaboration
| | - F. Abe
- Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, 464-8601, Japan
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - R. K. Barry
- Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - D. P. Bennett
- University of Notre Dame, Department of Physics, 225 Nieuwland Science Hall, Notre Dame, IN 46556-5670, USA
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - A. Bhattacharya
- University of Notre Dame, Department of Physics, 225 Nieuwland Science Hall, Notre Dame, IN 46556-5670, USA
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - I.A. Bond
- Institute of Information and Mathematical Sciences, Massey University, Private Bag 102-904, North Shore Mail Centre, Auckland, New Zealand
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - M. Freeman
- Department of Physics, University of Auckland, Private Bag 92-019, Auckland 1001, New Zealand
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - K. Inayama
- Department of Physics, Faculty of Science, Kyoto Sangyo University, 603-8555 Kyoto, Japan
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - Y. Itow
- Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, 464-8601, Japan
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - N. Koshimoto
- Department of Earth and Space Science, Osaka University, Osaka 560-0043, Japan
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - C.H. Ling
- Institute of Information and Mathematical Sciences, Massey University, Private Bag 102-904, North Shore Mail Centre, Auckland, New Zealand
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - K. Masuda
- Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, 464-8601, Japan
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - A. Fukui
- Okayama Astrophysical Observatory, National Astronomical Observatory of Japan, Asakuchi, Okayama 719-0232, Japan
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - Y. Matsubara
- Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, 464-8601, Japan
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - Y. Muraki
- Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, 464-8601, Japan
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - K. Ohnishi
- Nagano National College of Technology, Nagano 381-8550, Japan
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - N. J. Rattenbury
- Department of Physics, University of Auckland, Private Bag 92-019, Auckland 1001, New Zealand
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - To. Saito
- Tokyo Metropolitan College of Aeronautics, Tokyo 116-8523, Japan
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - D.J. Sullivan
- School of Chemical and Physical Sciences, Victoria University, Wellington, New Zealand
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - D. Suzuki
- University of Notre Dame, Department of Physics, 225 Nieuwland Science Hall, Notre Dame, IN 46556-5670, USA
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - P. J. Tristram
- Mt. John University Observatory, P.O. Box 56, Lake Tekapo 8770, New Zealand
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - Y. Wakiyama
- Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, 464-8601, Japan
- Microlensing Observations in Astrophysics (MOA) Collaboration
| | - A. Yonehara
- Department of Physics, Faculty of Science, Kyoto Sangyo University, 603-8555 Kyoto, Japan
- Microlensing Observations in Astrophysics (MOA) Collaboration
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3
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Howes LM, Casey AR, Asplund M, Keller SC, Yong D, Nataf DM, Poleski R, Lind K, Kobayashi C, Owen CI, Ness M, Bessell MS, Da Costa GS, Schmidt BP, Tisserand P, Udalski A, Szymański MK, Soszyński I, Pietrzyński G, Ulaczyk K, Wyrzykowski Ł, Pietrukowicz P, Skowron J, Kozłowski S, Mróz P. Extremely metal-poor stars from the cosmic dawn in the bulge of the Milky Way. Nature 2015; 527:484-7. [PMID: 26560034 DOI: 10.1038/nature15747] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 08/24/2015] [Indexed: 11/09/2022]
Abstract
The first stars are predicted to have formed within 200 million years after the Big Bang, initiating the cosmic dawn. A true first star has not yet been discovered, although stars with tiny amounts of elements heavier than helium ('metals') have been found in the outer regions ('halo') of the Milky Way. The first stars and their immediate successors should, however, preferentially be found today in the central regions ('bulges') of galaxies, because they formed in the largest over-densities that grew gravitationally with time. The Milky Way bulge underwent a rapid chemical enrichment during the first 1-2 billion years, leading to a dearth of early, metal-poor stars. Here we report observations of extremely metal-poor stars in the Milky Way bulge, including one star with an iron abundance about 10,000 times lower than the solar value without noticeable carbon enhancement. We confirm that most of the metal-poor bulge stars are on tight orbits around the Galactic Centre, rather than being halo stars passing through the bulge, as expected for stars formed at redshifts greater than 15. Their chemical compositions are in general similar to typical halo stars of the same metallicity although intriguing differences exist, including lower abundances of carbon.
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Affiliation(s)
- L M Howes
- Research School of Astronomy and Astrophysics, Australian National University, Australian Capital Territory 2601, Australia
| | - A R Casey
- Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK
| | - M Asplund
- Research School of Astronomy and Astrophysics, Australian National University, Australian Capital Territory 2601, Australia
| | - S C Keller
- Research School of Astronomy and Astrophysics, Australian National University, Australian Capital Territory 2601, Australia
| | - D Yong
- Research School of Astronomy and Astrophysics, Australian National University, Australian Capital Territory 2601, Australia
| | - D M Nataf
- Research School of Astronomy and Astrophysics, Australian National University, Australian Capital Territory 2601, Australia
| | - R Poleski
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland.,Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, Ohio 43210, USA
| | - K Lind
- Department of Physics and Astronomy, Division of Astronomy and Space Physics, Uppsala University, Box 516, SE-751 20 Uppsala, Sweden
| | - C Kobayashi
- Research School of Astronomy and Astrophysics, Australian National University, Australian Capital Territory 2601, Australia.,School of Physics, Astronomy and Mathematics, Centre for Astrophysics Research, University of Hertfordshire, College Lane, Hatfield AL10 9AB, UK
| | - C I Owen
- Research School of Astronomy and Astrophysics, Australian National University, Australian Capital Territory 2601, Australia
| | - M Ness
- Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg, Germany
| | - M S Bessell
- Research School of Astronomy and Astrophysics, Australian National University, Australian Capital Territory 2601, Australia
| | - G S Da Costa
- Research School of Astronomy and Astrophysics, Australian National University, Australian Capital Territory 2601, Australia
| | - B P Schmidt
- Research School of Astronomy and Astrophysics, Australian National University, Australian Capital Territory 2601, Australia
| | - P Tisserand
- Research School of Astronomy and Astrophysics, Australian National University, Australian Capital Territory 2601, Australia.,Sorbonne Universités, UPMC Université Paris 6 et CNRS, UMR 7095, Institut d'Astrophysique de Paris, 98 bis Boulevard Arago, 75014 Paris, France
| | - A Udalski
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - M K Szymański
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - I Soszyński
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - G Pietrzyński
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland.,Universidad de Concepción, Departamento de Astronomia, Casilla 160-C, Concepción, Chile
| | - K Ulaczyk
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland.,Department of Physics, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | - Ł Wyrzykowski
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - P Pietrukowicz
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - J Skowron
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - S Kozłowski
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - P Mróz
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
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4
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Udalski A, Yee JC, Gould A, Carey S, Zhu W, Skowron J, Kozłowski S, Poleski R, Pietrukowicz P, Pietrzyński G, Szymański MK, Mróz P, Soszyński I, Ulaczyk K, Wyrzykowski Ł, Han C, Calchi Novati S, Pogge RW. SPITZERAS A MICROLENS PARALLAX SATELLITE: MASS MEASUREMENT FOR THE OGLE-2014-BLG-0124L PLANET AND ITS HOST STAR. ACTA ACUST UNITED AC 2015. [DOI: 10.1088/0004-637x/799/2/237] [Citation(s) in RCA: 117] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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5
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Motch C, Pakull MW, Soria R, Grisé F, Pietrzyński G. A mass of less than 15 solar masses for the black hole in an ultraluminous X-ray source. Nature 2014; 514:198-201. [DOI: 10.1038/nature13730] [Citation(s) in RCA: 157] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Accepted: 07/28/2014] [Indexed: 11/09/2022]
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6
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Gould A, Udalski A, Shin IG, Porritt I, Skowron J, Han C, Yee JC, Kozłowski S, Choi JY, Poleski R, Wyrzykowski Ł, Ulaczyk K, Pietrukowicz P, Mróz P, Szymański MK, Kubiak M, Soszyński I, Pietrzyński G, Gaudi BS, Christie GW, Drummond J, McCormick J, Natusch T, Ngan H, Tan TG, Albrow M, DePoy DL, Hwang KH, Jung YK, Lee CU, Park H, Pogge RW, Abe F, Bennett DP, Bond IA, Botzler CS, Freeman M, Fukui A, Fukunaga D, Itow Y, Koshimoto N, Larsen P, Ling CH, Masuda K, Matsubara Y, Muraki Y, Namba S, Ohnishi K, Philpott L, Rattenbury NJ, Saito T, Sullivan DJ, Sumi T, Suzuki D, Tristram PJ, Tsurumi N, Wada K, Yamai N, Yock PCM, Yonehara A, Shvartzvald Y, Maoz D, Kaspi S, Friedmann M. Exoplanet detection. A terrestrial planet in a ~1-AU orbit around one member of a ~15-AU binary. Science 2014; 345:46-9. [PMID: 24994642 DOI: 10.1126/science.1251527] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Using gravitational microlensing, we detected a cold terrestrial planet orbiting one member of a binary star system. The planet has low mass (twice Earth's) and lies projected at ~0.8 astronomical units (AU) from its host star, about the distance between Earth and the Sun. However, the planet's temperature is much lower, <60 Kelvin, because the host star is only 0.10 to 0.15 solar masses and therefore more than 400 times less luminous than the Sun. The host itself orbits a slightly more massive companion with projected separation of 10 to 15 AU. This detection is consistent with such systems being very common. Straightforward modification of current microlensing search strategies could increase sensitivity to planets in binary systems. With more detections, such binary-star planetary systems could constrain models of planet formation and evolution.
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Affiliation(s)
- A Gould
- Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210, USA
| | - A Udalski
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - I-G Shin
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - I Porritt
- Turitea Observatory, Palmerston North, New Zealand
| | - J Skowron
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - C Han
- Department of Physics, Chungbuk National University, Cheongju 371-763, Republic of Korea.
| | - J C Yee
- Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210, USA. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA
| | - S Kozłowski
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - J-Y Choi
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - R Poleski
- Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210, USA. Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - Ł Wyrzykowski
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland. Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK
| | - K Ulaczyk
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - P Pietrukowicz
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - P Mróz
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - M K Szymański
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - M Kubiak
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - I Soszyński
- Warsaw University Observatory, Aleje Ujazdowskie 4, 00-478 Warszawa, Poland
| | - G Pietrzyński
- Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210, USA. Universidad de Concepción, Departamento de Astronomia, Casilla 160-C, Concepción, Chile
| | - B S Gaudi
- Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210, USA
| | | | - J Drummond
- Possum Observatory, Patutahi, New Zealand
| | - J McCormick
- Farm Cove Observatory, Centre for Backyard Astrophysics, Pakuranga, Auckland, New Zealand
| | - T Natusch
- Possum Observatory, Patutahi, New Zealand. Auckland University of Technology, Auckland, New Zealand
| | - H Ngan
- Possum Observatory, Patutahi, New Zealand
| | - T-G Tan
- Perth Exoplanet Survey Telescope, Perth, Australia
| | - M Albrow
- Department of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
| | - D L DePoy
- Department of Physics and Astronomy, Texas A&M University, College Station, TX 77843-4242, USA
| | - K-H Hwang
- Department of Physics, Chungbuk National University, Cheongju 371-763, Republic of Korea
| | - Y K Jung
- Department of Physics, Chungbuk National University, Cheongju 371-763, Republic of Korea
| | - C-U Lee
- Korea Astronomy and Space Science Institute, Daejeon 305-348, Republic of Korea
| | - H Park
- Department of Physics, Chungbuk National University, Cheongju 371-763, Republic of Korea
| | - R W Pogge
- Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210, USA
| | - F Abe
- Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya 464-8601, Japan
| | - D P Bennett
- University of Notre Dame, Department of Physics, 225 Nieuwland Science Hall, Notre Dame, IN 46556-5670, USA
| | - I A Bond
- Institute of Information and Mathematical Sciences, Massey University, Private Bag 102-904, North Shore Mail Centre, Auckland, New Zealand
| | - C S Botzler
- Department of Physics, University of Auckland, Private Bag 92-019, Auckland 1001, New Zealand
| | - M Freeman
- Department of Physics, University of Auckland, Private Bag 92-019, Auckland 1001, New Zealand
| | - A Fukui
- Okayama Astrophysical Observatory, National Astronomical Observatory of Japan, Asakuchi, Okayama 719-0232, Japan
| | - D Fukunaga
- Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya 464-8601, Japan
| | - Y Itow
- Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya 464-8601, Japan
| | - N Koshimoto
- Department of Earth and Space Science, Osaka University, Osaka 560-0043, Japan
| | - P Larsen
- Department of Physics, University of Auckland, Private Bag 92-019, Auckland 1001, New Zealand. Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK
| | - C H Ling
- Institute of Information and Mathematical Sciences, Massey University, Private Bag 102-904, North Shore Mail Centre, Auckland, New Zealand
| | - K Masuda
- Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya 464-8601, Japan
| | - Y Matsubara
- Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya 464-8601, Japan
| | - Y Muraki
- Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya 464-8601, Japan
| | - S Namba
- Department of Earth and Space Science, Osaka University, Osaka 560-0043, Japan
| | - K Ohnishi
- Nagano National College of Technology, Nagano 381-8550, Japan
| | - L Philpott
- Department of Earth, Ocean and Atmospheric Sciences, The University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - N J Rattenbury
- Department of Physics, University of Auckland, Private Bag 92-019, Auckland 1001, New Zealand
| | - To Saito
- Tokyo Metropolitan College of Aeronautics, Tokyo 116-8523, Japan
| | - D J Sullivan
- School of Chemical and Physical Sciences, Victoria University, Wellington, New Zealand
| | - T Sumi
- Department of Earth and Space Science, Osaka University, Osaka 560-0043, Japan
| | - D Suzuki
- Department of Earth and Space Science, Osaka University, Osaka 560-0043, Japan
| | - P J Tristram
- Mount John University Observatory, Post Office Box 56, Lake Tekapo 8770, New Zealand
| | - N Tsurumi
- Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya 464-8601, Japan
| | - K Wada
- Department of Earth and Space Science, Osaka University, Osaka 560-0043, Japan
| | - N Yamai
- Department of Physics, Faculty of Science, Kyoto Sangyo University, Kyoto 603-8555, Japan
| | - P C M Yock
- Department of Physics, University of Auckland, Private Bag 92-019, Auckland 1001, New Zealand
| | - A Yonehara
- Department of Physics, Faculty of Science, Kyoto Sangyo University, Kyoto 603-8555, Japan
| | - Y Shvartzvald
- School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978, Israel
| | - D Maoz
- School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978, Israel
| | - S Kaspi
- School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978, Israel
| | - M Friedmann
- School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978, Israel
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7
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Beaulieu JP, Bennett DP, Fouqué P, Williams A, Dominik M, Jørgensen UG, Kubas D, Cassan A, Coutures C, Greenhill J, Hill K, Menzies J, Sackett PD, Albrow M, Brillant S, Caldwell JAR, Calitz JJ, Cook KH, Corrales E, Desort M, Dieters S, Dominis D, Donatowicz J, Hoffman M, Kane S, Marquette JB, Martin R, Meintjes P, Pollard K, Sahu K, Vinter C, Wambsganss J, Woller K, Horne K, Steele I, Bramich DM, Burgdorf M, Snodgrass C, Bode M, Udalski A, Szymański MK, Kubiak M, Wieckowski T, Pietrzyński G, Soszyński I, Szewczyk O, Wyrzykowski L, Paczyński B, Abe F, Bond IA, Britton TR, Gilmore AC, Hearnshaw JB, Itow Y, Kamiya K, Kilmartin PM, Korpela AV, Masuda K, Matsubara Y, Motomura M, Muraki Y, Nakamura S, Okada C, Ohnishi K, Rattenbury NJ, Sako T, Sato S, Sasaki M, Sekiguchi T, Sullivan DJ, Tristram PJ, Yock PCM, Yoshioka T. Discovery of a cool planet of 5.5 Earth masses through gravitational microlensing. Nature 2006; 439:437-40. [PMID: 16437108 DOI: 10.1038/nature04441] [Citation(s) in RCA: 466] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2005] [Accepted: 11/14/2005] [Indexed: 11/08/2022]
Abstract
In the favoured core-accretion model of formation of planetary systems, solid planetesimals accumulate to build up planetary cores, which then accrete nebular gas if they are sufficiently massive. Around M-dwarf stars (the most common stars in our Galaxy), this model favours the formation of Earth-mass (M(o)) to Neptune-mass planets with orbital radii of 1 to 10 astronomical units (au), which is consistent with the small number of gas giant planets known to orbit M-dwarf host stars. More than 170 extrasolar planets have been discovered with a wide range of masses and orbital periods, but planets of Neptune's mass or less have not hitherto been detected at separations of more than 0.15 au from normal stars. Here we report the discovery of a 5.5(+5.5)(-2.7) M(o) planetary companion at a separation of 2.6+1.5-0.6 au from a 0.22+0.21-0.11 M(o) M-dwarf star, where M(o) refers to a solar mass. (We propose to name it OGLE-2005-BLG-390Lb, indicating a planetary mass companion to the lens star of the microlensing event.) The mass is lower than that of GJ876d (ref. 5), although the error bars overlap. Our detection suggests that such cool, sub-Neptune-mass planets may be more common than gas giant planets, as predicted by the core accretion theory.
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Affiliation(s)
- J-P Beaulieu
- PLANET/RoboNet Collaboration, CNRS, Université Pierre et Marie Curie UMR7095, 98bis Boulevard Arago, 75014 Paris, France.
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8
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Broda MA, Rzeszotarska B, Smełka L, Pietrzyński G. Conformational investigation of alpha,beta-dehydropeptides. IX. N-Acetyl-(E)-alpha,beta-methylamide: stereoelectronic properties from infrared and theoretical studies. J Pept Res 1998; 52:72-9. [PMID: 9716253 DOI: 10.1111/j.1399-3011.1998.tb00654.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The Fourier transform infrared spectra of Ac-(E)-deltaAbu-NHMe were analyzed to determine the predominant solution conformation(s) of this (E)-alpha,beta-dehydropeptide-related compound and the electron density perturbation in its amide groups. The measurements were performed in dichloromethane and acetonitrile in the region of mode vs (N-H), amide I, amide II and vs (C(alpha)=Cbeta). The equilibrium geometrical parameters, calculated by a method based on the density functional theory with the B3LYP functional and the 6-31G* basis set, were used to support spectroscopic interpretation and gain some deeper insight into the molecule. The experimental and theoretical data were compared with those of three previously described molecules: isomeric Ac-(Z)-deltaAbu-NHMe, Ac-deltaAla-NHMe, which is deprived of any beta-substituent, and saturated species Ac-Abu-NHMe. The titled compound assumes two conformational states in equilibrium in the DCM solution. One conformer is extended almost fully and like Ac-deltaAla-NHMe is C5 hydrogen-bonded. The other adopts a warped C5 structure similar to that of Ac-(Z)-deltaAbu-NHMe. The C5 hydrogen bond, unlike the H-bond in Ac-deltaAla-NHMe, is disrupted by acetonitrile. The resonance within the N-terminal amide groups in either of the (E)-deltaAbu conformers is not as well developed as the resonance in Ac-Abu-NHMe. However, these N-terminal groups, compared with the other unsaturated compounds, constitute better resonance systems in each conformationally related couple: the C5 hydrogen-bonded Ac-(E)-deltaAbu-NHMe/Ac-deltaAla-NHMe and the warped C5 Ac-(E)-deltaAbu-NHMe/Ac-(Z)-deltaAbu-NHMe. The resonance within the C-terminal groups of the latter couple apparently is similar, but less developed than the resonance in Ac-Abu-NHMe. The electron distribution within the C-terminal group of the hydrogen-bonded C5 (E)-deltaAbu conformer apparently is determined mainly by the electron influx from the C(alpha)=Cbeta double bond.
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Affiliation(s)
- M A Broda
- Department of Organic Chemistry, University of Opole, Poland
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9
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Pietrzyński G, Rzeszotarska B, Ciszak E, Lisowski M, Kubica Z, Boussard G. Conformational investigation of alpha,beta-dehydropeptides. VII. Conformation of Ac-Pro-deltaAla-NHCH3 and Ac-Pro-(E)-deltaAbu-NHCH3: comparison with (Z)-substituted alpha,beta-dehydropeptides. Int J Pept Protein Res 1996; 48:347-56. [PMID: 8919055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The crystal structure and solution conformation of Ac-Pro-deltaAla-NHCH3 and the solution conformation of Ac-Pro-(E)-deltaAbu-NHCH3 were investigated by X-ray diffraction method and NMR, FTIR and CD spectroscopies. Ac-Pro-deltaAla-NHCH3 adopts an extended-coil conformation in the crystalline state, with all-trans peptide bonds and the deltaAla residue being in a C5 form, phi(1)=-71.4(4), psi(1)=-16.8(4), phi(2)= -178.4(3) and psi(2)= 172.4(3) degrees. In inert solvents the peptide also assumes the C5 conformation, but a gamma-turn on the Pro residue cannot be ruled out. In these solvents Ac-Pro-(E)-deltaAbu-NHCH3 accommodates a beta(II)-turn, but a minor conformer with a nearly planar disposition of the CO-NH and C=C bonds (phi(2) approximately 0 degrees) is also present. Previous spectroscopic studies of the (Z)-substituted dehydropeptides Ac-Pro-(Z)-deltaAbu-NHCH3 and Ac-Pro-deltaVal-NHCH3 reveal that both peptides prefer a beta(II)-turn in solution. Comparison of conformations in the family of four Ac-Pro-deltaXaa-NHCH3 peptides let us formulate the following order of their tendency to adopt a beta-turn in solution: (Z)-deltaAbu > (E)-deltaAbu > deltaVal; deltaAla does not. None of the folded structures formed by the four compounds is stable in strongly solvating media.
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Affiliation(s)
- G Pietrzyński
- Department of Organic Chemistry, University of Opole, Poland.
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10
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Lisowski M, Pietrzyński G, Rzeszotarska B. Conformational investigation of alpha, beta-dehydropeptides. V*. Stability of reverse turns in saturated and alpha, beta-unsaturated peptides Ac-Pro-Xaa-NHCH3: CD studies in various solvents. Int J Pept Protein Res 1993; 42:466-74. [PMID: 8106199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Conformations of three series of model peptides: homochiral Ac-Pro-L-Xaa-NHCH3 and heterochiral Ac-Pro-D-Xaa-NHCH3 (Xaa = Phe, Val, Leu, Abu, Ala) as well as alpha, beta-dehydro Ac-Pro-delta Xaa-NHCH3 [delta Xaa = (Z)-delta Phe, delta Val,(Z)-delta Leu,(Z)-delta Abu] were investigated by CD spectroscopy in 2% dichloromethane-cyclohexane, trifluoroethanol, water, and occasionally in other solvents. The spectra of homochiral peptides show a significant solvent dependence. Folded structures are present in 2% dichloromethane-cyclohexane and unordered ones occur in water. The folded conformers are of the inverse gamma-turn type for all the peptides but Ac-Pro-L-Phe-NHCH3 for which the type-I beta-turn is preferred. The changes in the spectra of the heterochiral peptides are limited. The compounds adopt the type-II beta-turn in 2% dichloromethane-cyclohexane, represented by class B spectra, and retain this conformation in water as well as in fluorinated alcohols but not always to a full extent. The CD spectra of the unsaturated peptides in 2% dichloromethane-cyclohexane, although they cannot be assigned to any common spectral class, must be attributed to the beta II-turn conformation as determined for these compounds by NMR and IR spectroscopy. The CD spectra of dehydropeptides exhibit a considerable solvent dependence and suggest unordered structures in water.
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Affiliation(s)
- M Lisowski
- Institute of Chemistry, University of Wrocław, Poland
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11
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Ciszak E, Pietrzyński G, Rzeszotarska B. Conformational investigation of alpha, beta-dehydropeptides. Part III. Molecular and crystal structure of acetyl-L-prolyl-alpha, beta-dehydrovaline methylamide. Int J Pept Protein Res 1992; 39:218-22. [PMID: 1399260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The crystal structure of Ac-Pro-delta Val-NHCH3 was examined to determine the influence of the alpha,beta-dehydrovaline residue on the nature of peptide conformation. The peptide crystallizes from methanol-diethyl ether solution at 4 degrees in needle-shaped form in orthorhombic space group P2(1)2(1)2(1) with a = 11.384(2) A, b = 13.277(2) A, c = 9.942(1) A, V = 1502.7(4) A3, Z = 4, Dm = 1.17 g.cm-3 and Dc = 1.18 g.cm-3. The structure was solved by direct methods using SHELXS-86 and refined to an R value of 0.057 for 1922 observed reflections. The peptide is found to adopt a beta-bend between the type I and the type III conformation with phi 1 = -68.3(4) degrees, psi 1 = -20.1(4) degrees, phi 2 = -73.5(4) degrees and psi 2 = -14.1(4) degrees. An intramolecular hydrogen bond between the carbonyl oxygen of ith residue and the NH of (i + 3)th residue stabilizes the beta-bend. An additional intermolecular N...O hydrogen bond joins molecules into infinite chains. In the literature described crystal structures of peptides having a single alpha,beta-dehydroamino acid residue in the (i + 2) position and forming a beta-bend reveal a type II conformation.
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Affiliation(s)
- E Ciszak
- Department of Organic Chemistry, Pedagogical University of Opole, Poland
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