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Related papers: Revisiting hypervelocity stars after Gaia DR2

200 papers

We obtain Keck HIRES spectroscopy of HVS5, one of the fastest unbound stars in the Milky Way halo. We show that HVS5 is a 3.62 +- 0.11 Msun main sequence B star at a distance of 50 +- 5 kpc. The difference between its age and its flight…

Astrophysics of Galaxies · Physics 2015-06-05 Warren R. Brown , Judith G. Cohen , Margaret J. Geller , Scott J. Kenyon

The disruption of binary stars by the tidal field of the black hole in the Galactic Center can produce the hypervelocity stars observed in the halo. We use numerical models to simulate the full spectrum of observable velocities of stars…

The Milky Way Galaxy hosts a four million solar mass black hole, Sgr A*, that underwent a major accretion episode approximately 3-6 Myr ago. During the episode, hundreds of young massive stars formed in a disc orbiting Sgr A* in the central…

Astrophysics of Galaxies · Physics 2022-05-30 A. Generozov , S. Nayakshin , A. M. Madigan

The second Gaia data release (Gaia DR2) provided us with the precise five-parameter astrometry for 1.3 billion of sources. As stars passing close to the Solar System are thought to be responsible for influencing the dynamical history of…

Earth and Planetary Astrophysics · Physics 2022-01-31 Rita Wysoczańska , Piotr A. Dybczyński , Magdalena Polińska

Type Ia supernovae arise from thermonuclear explosions of white dwarfs accreting from a binary companion. Following the explosion, the surviving donor star leaves at roughly its orbital velocity. The discovery of the runaway helium subdwarf…

Solar and Stellar Astrophysics · Physics 2024-09-02 Tin Long Sunny Wong , Christopher White , Lars Bildsten

We verify candidate hypervelocity red clump stars located in the Galactic bulge that were selected based on the VVV and the Gaia DR2 data by Luna et al. (2019). To do so, we analyze data from the OGLE-IV survey: difference images and…

Solar and Stellar Astrophysics · Physics 2024-03-07 Gabriela Wojtkowska , Radosław Poleski

Recent discoveries have shown that a population of hypervelocity stars (HVSs) originate from the Large Magellanic Cloud (LMC). We use three such HVSs as dynamical tracers to constrain the past orbit of the LMC. Since each star was ejected…

Astrophysics of Galaxies · Physics 2026-04-07 Scott Lucchini , Jiwon Jesse Han

We demonstrate that stars beyond the virial radii of galaxies may be generated by the gravitational impulse received by a satellite as it passes through the pericenter of its orbit around its parent. These stars may become energetically…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Maureen Teyssier , Kathryn V. Johnston , Michael Shara

We present a catalog of 3354 candidate young stars within 500 pc that appear to have been ejected from their parent associations with relative speeds of >5 km/s. These candidates have been homogeneously selected through performing a 2d…

Solar and Stellar Astrophysics · Physics 2022-10-12 Marina Kounkel , Aidan McBride , Keivan G. Stassun , Nathan Leigh

Hypervelocity stars (HVSs) discovered in the Milky Way (MW) halo are thought to be ejected from near the massive black hole (MBH) at the galactic centre. In this paper we investigate the spatial and velocity distributions of the HVSs which…

Astrophysics · Physics 2009-11-13 Blake D. Sherwin , Abraham Loeb , Ryan M. O'Leary

The study of open star clusters makes us understand a lot about the composition and construction of the Milky Way Galaxy. Thanks to the Gaia DR2 database that helps us to get the genetic members of star clusters using their proper motions…

Astrophysics of Galaxies · Physics 2021-09-23 W. A. Badawy , A. L. Tadross , Y. M. Hendy , I. A. Hassan , M. N. Ismail

Data from the Gaia satellite show that the solar neighbourhood of the Milky Way's stellar halo is imprinted with substructure from several accretion events. Evidence of these events is found in "the Shards", stars clustering with high…

Astrophysics of Galaxies · Physics 2020-01-15 Ciaran A. J. O'Hare , N. Wyn Evans , Christopher McCabe , GyuChul Myeong , Vasily Belokurov

Although the stellar halo accounts for just ~1% of the total stellar mass of the Milky Way, the kinematics of halo stars encode valuable information about the origins and evolution of our Galaxy. It has been shown that the high transverse…

Astrophysics of Galaxies · Physics 2020-01-15 João A. S. Amarante , Martin C. Smith , Corrado Boeche

We report the detection of five high-velocity stars in the core of the globular cluster NGC 2808. The stars lie on the the red giant branch and show total velocities between 40 and 45 km/s. For a core velocity dispersion sigma_c = 13.4…

Context: Hyper-velocity stars move so fast that only a supermassive black hole (SMBH) seems to be capable to accelerate them. Hence the Galactic centre (GC) is their only suggested place of origin. Edelmann et al. (2005) found the early…

Astrophysics · Physics 2009-11-13 N. Przybilla , M. F. Nieva , U. Heber , M. Firnstein , K. Butler , R. Napiwotzki , H. Edelmann

The escape velocity profile of the Milky Way offers a crucial and independent measurement of its underlying mass distribution and dark matter properties. Using a sample of stars from Gaia DR3 with 6D kinematics and strict quality cuts, we…

Astrophysics of Galaxies · Physics 2024-02-02 Cian Roche , Lina Necib , Tongyan Lin , Xiaowei Ou , Tri Nguyen

Supermassive black holes (SMBHs) in galactic nuclei can eject hypervelocity stars (HVSs). Using restricted three-body integrations, we study the properties of stars ejected by circular, binary SMBHs as a function of their mass ratios $q =…

Astrophysics of Galaxies · Physics 2018-10-24 Siva Darbha , Eric R. Coughlin , Daniel Kasen , Eliot Quataert

OB stars generally form in open clusters within the Milky Way's thin disk, so when they are found at high Galactic latitudes, it is thought that they were ejected from their birth clusters during the past few tens of millions of years.…

Solar and Stellar Astrophysics · Physics 2026-02-20 Brandon Schweers , M. Virginia McSwain

Only a few of the dozen or so stellar-mass black holes have been observed away from the plane of the Galaxy$^1$. Those few could have been ejected from the plane as a result of a ``kick'' received during a supernova explosion, or they could…

Astrophysics · Physics 2015-06-24 I. F. Mirabel , V. Dhawan , R. P. Mignani , I. Rodrigues , F. Guglielmetti

We estimate the distribution of ejection velocities for the known population of high galactic latitude runaway stars. The initial sample is a collection of 174 early-type stars selected from the literature. The stars are first classified…

Solar and Stellar Astrophysics · Physics 2015-05-20 M. D. V. Silva , R. Napiwotzki