1
|
|
2
|
Boyarsky A, Franse J, Iakubovskyi D, Ruchayskiy O. Checking the Dark Matter Origin of a 3.53 keV Line with the Milky Way Center. PHYSICAL REVIEW LETTERS 2015; 115:161301. [PMID: 26550860 DOI: 10.1103/physrevlett.115.161301] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Indexed: 06/05/2023]
Abstract
We detect a line at 3.539±0.011 keV in the deep exposure data set of the Galactic center region, observed with the x-ray multi-mirror mission Newton. The dark matter interpretation of the signal observed in the Perseus galaxy cluster, the Andromeda galaxy [A. Boyarsky et al., Phys. Rev. Lett. 113, 251301 (2014)], and in the stacked spectra of galaxy clusters [E. Bulbul et al., Astrophys. J. 789, 13 (2014)], together with nonobservation of the line in blank-sky data, put both lower and upper limits on the possible intensity of the line in the Galactic center data. Our result is consistent with these constraints for a class of Milky Way mass models, presented previously by observers, and would correspond to the radiative decay dark matter lifetime, τDM∼6-8×10(27) sec. Although it is hard to exclude an astrophysical origin of this line based on the Galactic center data alone, this is an important consistency check of the hypothesis that encourages us to check it with more observational data that are expected by the end of 2015.
Collapse
Affiliation(s)
- A Boyarsky
- Instituut-Lorentz for Theoretical Physics, Universiteit Leiden, Niels Bohrweg 2, Leiden, The Netherlands
| | - J Franse
- Instituut-Lorentz for Theoretical Physics, Universiteit Leiden, Niels Bohrweg 2, Leiden, The Netherlands
- Leiden Observatory, Leiden University, Niels Bohrweg 2, Leiden, The Netherlands
| | - D Iakubovskyi
- Bogolyubov Institute of Theoretical Physics, Metrologichna Street 14-b, 03680 Kyiv, Ukraine
| | - O Ruchayskiy
- Ecole Polytechnique Fédérale de Lausanne, FSB/ITP/LPPC, BSP, CH-1015 Lausanne, Switzerland
| |
Collapse
|
3
|
Boyarsky A, Ruchayskiy O, Iakubovskyi D, Franse J. Unidentified line in x-ray spectra of the Andromeda galaxy and Perseus galaxy cluster. PHYSICAL REVIEW LETTERS 2014; 113:251301. [PMID: 25554871 DOI: 10.1103/physrevlett.113.251301] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Indexed: 06/04/2023]
Abstract
We report a weak line at 3.52±0.02 keV in x-ray spectra of the Andromeda galaxy and the Perseus galaxy cluster observed by the metal-oxide-silicon (MOS) and p-n (PN) CCD cameras of the XMM-Newton telescope. This line is not known as an atomic line in the spectra of galaxies or clusters. It becomes stronger towards the centers of the objects; is stronger for Perseus than for M31; is absent in the spectrum of a deep "blank sky" data set. Although for each object it is hard to exclude that the feature is due to an instrumental effect or an atomic line, it is consistent with the behavior of a dark matter decay line. Future (non-)detections of this line in multiple objects may help to reveal its nature.
Collapse
Affiliation(s)
- A Boyarsky
- Instituut-Lorentz for Theoretical Physics, Universiteit Leiden, Niels Bohrweg 2, 2333 CA Leiden, Netherlands
| | - O Ruchayskiy
- Ecole Polytechnique Fédérale de Lausanne, FSB/ITP/LPPC, BSP, CH-1015 Lausanne, Switzerland
| | - D Iakubovskyi
- Bogolyubov Institute of Theoretical Physics, Metrologichna Street 14-b, 03680 Kyiv, Ukraine and National University "Kyiv-Mohyla Academy", Skovorody Street 2, 04070 Kyiv, Ukraine
| | - J Franse
- Instituut-Lorentz for Theoretical Physics, Universiteit Leiden, Niels Bohrweg 2, 2333 CA Leiden, Netherlands and Leiden Observatory, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, Netherlands
| |
Collapse
|
4
|
McDonald M, Benson BA, Vikhlinin A, Aird KA, Allen SW, Bautz M, Bayliss M, Bleem LE, Bocquet S, Brodwin M, Carlstrom JE, Chang CL, Cho HM, Clocchiatti A, Crawford TM, Crites AT, de Haan T, Dobbs MA, Foley RJ, Forman WR, George EM, Gladders MD, Gonzalez AH, Halverson NW, Hlavacek-Larrondo J, Holder GP, Holzapfel WL, Hrubes JD, Jones C, Keisler R, Knox L, Lee AT, Leitch EM, Liu J, Lueker M, Luong-Van D, Mantz A, Marrone DP, McMahon JJ, Meyer SS, Miller ED, Mocanu L, Mohr JJ, Murray SS, Padin S, Pryke C, Reichardt CL, Rest A, Ruhl JE, Saliwanchik BR, Saro A, Sayre JT, Schaffer KK, Shirokoff E, Spieler HG, Stalder B, Stanford SA, Staniszewski Z, Stark AA, Story KT, Stubbs CW, Vanderlinde K, Vieira JD, Williamson R, Zahn O, Zenteno A. THE REDSHIFT EVOLUTION OF THE MEAN TEMPERATURE, PRESSURE, AND ENTROPY PROFILES IN 80 SPT-SELECTED GALAXY CLUSTERS. ACTA ACUST UNITED AC 2014. [DOI: 10.1088/0004-637x/794/1/67] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
5
|
Tananbaum H, Weisskopf MC, Tucker W, Wilkes B, Edmonds P. Highlights and discoveries from the Chandra X-ray Observatory. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2014; 77:066902. [PMID: 24913425 DOI: 10.1088/0034-4885/77/6/066902] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Within 40 years of the detection of the first extra-solar x-ray source in 1962, NASA's Chandra X-ray Observatory has achieved an increase in sensitivity of 10 orders of magnitude, comparable to the gain in going from naked-eye observations to the most powerful optical telescopes over the past 400 years. Chandra is unique in its capabilities for producing sub-arcsecond x-ray images with 100-200 eV energy resolution for energies in the range 0.08 < E < 10 keV, locating x-ray sources to high precision, detecting extremely faint sources, and obtaining high-resolution spectra of selected cosmic phenomena. The extended Chandra mission provides a long observing baseline with stable and well-calibrated instruments, enabling temporal studies over timescales from milliseconds to years. In this report we present a selection of highlights that illustrate how observations using Chandra, sometimes alone, but often in conjunction with other telescopes, have deepened, and in some instances revolutionized, our understanding of topics as diverse as protoplanetary nebulae; massive stars; supernova explosions; pulsar wind nebulae; the superfluid interior of neutron stars; accretion flows around black holes; the growth of supermassive black holes and their role in the regulation of star formation and growth of galaxies; impacts of collisions, mergers, and feedback on growth and evolution of groups and clusters of galaxies; and properties of dark matter and dark energy.
Collapse
Affiliation(s)
- H Tananbaum
- Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138, USA
| | | | | | | | | |
Collapse
|
6
|
A uniform metal distribution in the intergalactic medium of the Perseus cluster of galaxies. Nature 2013; 502:656-8. [PMID: 24172976 DOI: 10.1038/nature12646] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2013] [Accepted: 09/09/2013] [Indexed: 11/09/2022]
Abstract
Most of the metals (elements heavier than helium) produced by stars in the member galaxies of clusters currently reside within the hot, X-ray-emitting intra-cluster gas. Observations of X-ray line emission from this intergalactic medium have suggested a relatively small cluster-to-cluster scatter outside the cluster centres and enrichment with iron out to large radii, leading to the idea that the metal enrichment occurred early in the history of the Universe. Models with early enrichment predict a uniform metal distribution at large radii in clusters, whereas those with late-time enrichment are expected to introduce significant spatial variations of the metallicity. To discriminate clearly between these competing models, it is essential to test for potential inhomogeneities by measuring the abundances out to large radii along multiple directions in clusters, which has not hitherto been done. Here we report a remarkably uniform iron abundance, as a function of radius and azimuth, that is statistically consistent with a constant value of ZFe = 0.306 ± 0.012 in solar units out to the edge of the nearby Perseus cluster. This homogeneous distribution requires that most of the metal enrichment of the intergalactic medium occurred before the cluster formed, probably more than ten billion years ago, during the period of maximal star formation and black hole activity.
Collapse
|
7
|
Braun R. The cosmic web in focus. Nature 2013; 497:191-2. [DOI: 10.1038/497191a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
8
|
Famaey B, McGaugh SS. Modified Newtonian Dynamics (MOND): Observational Phenomenology and Relativistic Extensions. LIVING REVIEWS IN RELATIVITY 2012; 15:10. [PMID: 28163623 PMCID: PMC5255531 DOI: 10.12942/lrr-2012-10] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 04/30/2012] [Indexed: 05/27/2023]
Abstract
A wealth of astronomical data indicate the presence of mass discrepancies in the Universe. The motions observed in a variety of classes of extragalactic systems exceed what can be explained by the mass visible in stars and gas. Either (i) there is a vast amount of unseen mass in some novel form - dark matter - or (ii) the data indicate a breakdown of our understanding of dynamics on the relevant scales, or (iii) both. Here, we first review a few outstanding challenges for the dark matter interpretation of mass discrepancies in galaxies, purely based on observations and independently of any alternative theoretical framework. We then show that many of these puzzling observations are predicted by one single relation - Milgrom's law - involving an acceleration constant a0 (or a characteristic surface density Σ† = a0/G) on the order of the square-root of the cosmological constant in natural units. This relation can at present most easily be interpreted as the effect of a single universal force law resulting from a modification of Newtonian dynamics (MOND) on galactic scales. We exhaustively review the current observational successes and problems of this alternative paradigm at all astrophysical scales, and summarize the various theoretical attempts (TeVeS, GEA, BIMOND, and others) made to effectively embed this modification of Newtonian dynamics within a relativistic theory of gravity.
Collapse
Affiliation(s)
- Benoît Famaey
- Observatoire Astronomique de Strasbourg, CNRS, UMR 7550, Paris, France
- AIfA, University of Bonn, Bonn, Germany
| | - Stacy S. McGaugh
- Department of Astronomy, University of Maryland, College Park, USA
- Case Western Reserve University, Cleveland, USA
| |
Collapse
|
9
|
A filament of dark matter between two clusters of galaxies. Nature 2012; 487:202-4. [DOI: 10.1038/nature11224] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Accepted: 05/11/2012] [Indexed: 11/08/2022]
|
10
|
Parrish IJ, McCourt M, Quataert E, Sharma P. Turbulent pressure support in the outer parts of galaxy clusters. ACTA ACUST UNITED AC 2011. [DOI: 10.1111/j.1745-3933.2011.01171.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|