RR Lyrae variables in Messier 53: Near-infrared Period–Luminosity relations and the calibration using Gaia Early Data Release 3

Kavli Affiliate: Gregory J. Herczeg | First 5 Authors: Anupam Bhardwaj, Marina Rejkuba, Richard de Grijs, Soung-Chul Yang, Gregory J. Herczeg | Summary: We present new near-infrared, $JHK_s$, Period–Luminosity relations (PLRs) for RR Lyrae variables in the Messier 53 (M53 or NGC 5024) globular cluster. Multi-epoch $JHK_s$ observations, obtained with the WIRCam instrument on the […]


Continue.. RR Lyrae variables in Messier 53: Near-infrared Period–Luminosity relations and the calibration using Gaia Early Data Release 3

X-ray flares from the stellar tidal disruption by a candidate supermassive black hole binary

Kavli Affiliate: Fukun Liu | First 5 Authors: Xinwen Shu, Wenjie Zhang, Shuo Li, Ning Jiang, Liming Dou | Summary: Optical transient surveys have led to the discovery of dozens of stellar tidal disruption events (TDEs) by massive black hole in the centers of galaxies. Despite extensive searches, X-ray follow-up observations have produced no or […]


Continue.. X-ray flares from the stellar tidal disruption by a candidate supermassive black hole binary

X-ray flares from the stellar tidal disruption by a candidate supermassive black hole binary

Kavli Affiliate: Fukun Liu | First 5 Authors: Xinwen Shu, Wenjie Zhang, Shuo Li, Ning Jiang, Liming Dou | Summary: Optical transient surveys have led to the discovery of dozens of stellar tidal disruption events (TDEs) by massive black hole in the centers of galaxies. Despite extensive searches, X-ray follow-up observations have produced no or […]


Continue.. X-ray flares from the stellar tidal disruption by a candidate supermassive black hole binary

Discovery of A candidate Hypervelocity star originated from the Sagittarius Dwarf Spheroidal galaxy

Kavli Affiliate: Huawei Zhang | First 5 Authors: Yang Huang, Qingzheng Li, Huawei Zhang, Xinyi Li, Weixiang Sun | Summary: In this letter, we report the discovery of an intriguing HVS (J1443+1453) candidate that is probably from the Sagittarius Dwarf Spheroidal galaxy (Sgr dSph). The star is an old and very metal-poor low-mass main-sequence turn-off […]


Continue.. Discovery of A candidate Hypervelocity star originated from the Sagittarius Dwarf Spheroidal galaxy

Discovery of a damped Ly$α$ galaxy at z $sim$ 3 towards the quasar SDSS J011852+040644

Kavli Affiliate: Linhua Jiang | First 5 Authors: Ravi Joshi, Michele Fumagalli, Raghunathan Srianand, Pasquier Noterdaeme, Patrick Petitjean | Summary: We report the detection of the host galaxy of a damped Ly$alpha$ system (DLA) with log N(HI) $ [rm cm^{-2}]$ = $21.0 pm 0.10$ at $z approx 3.0091$ towards the background quasar SDSS J011852+040644 using […]


Continue.. Discovery of a damped Ly$α$ galaxy at z $sim$ 3 towards the quasar SDSS J011852+040644

A possible bright ultraviolet flash from a galaxy at redshift z ~ 11

Kavli Affiliate: Linhua Jiang | First 5 Authors: Linhua Jiang, Shu Wang, Bing Zhang, Nobunari Kashikawa, Luis C. Ho | Summary: In the optical sky, minutes-duration transients from cosmological distances are rare. Known objects that give rise to such transients include gamma-ray bursts (GRBs), the most luminous explosions in the universe that have been detected […]


Continue.. A possible bright ultraviolet flash from a galaxy at redshift z ~ 11

Elliptical accretion disk as a model for tidal disruption events

Kavli Affiliate: Fukun Liu | First 5 Authors: Fukun Liu, Chunyang Cao, Marek A. Abramowicz, Maciek Wielgus, Rong Cao | Summary: Elliptical accretion disk models for tidal disruption events (TDEs) have been recently proposed and independently developed by two groups. Although these two models are characterized by a similar geometry, their physical properties differ considerably. […]


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Black holes and the supermassive compact object at the Galactic center: multi-arts of thought and nature

Kavli Affiliate: Qingjuan Yu | First 5 Authors: Qingjuan Yu, , , , | Summary: This is an invited commentary on the Nobel Prize in Physics 2020 which was awarded to Roger Penrose "for the discovery that black hole formation is a robust prediction of the general theory of relativity," and Reinhard Genzel and Andrea […]


Continue.. Black holes and the supermassive compact object at the Galactic center: multi-arts of thought and nature

Cosmic distributions of stellar tidal disruptions by massive black holes at galactic centers

Kavli Affiliate: Qingjuan Yu | First 5 Authors: Yunfeng Chen, Qingjuan Yu, Youjun Lu, , | Summary: Stars can be consumed (either tidally disrupted or swallowed whole) by massive black holes (MBHs) at galactic centers when they move into the vicinity of the MBHs. In this study, we investigate the rates of stellar consumption by […]


Continue.. Cosmic distributions of stellar tidal disruptions by massive black holes at galactic centers

The long-term evolution of main-sequence binaries in DRAGON simulations

Kavli Affiliate: Rainer Spurzem | First 5 Authors: Qi Shu, Xiaoying Pang, Francesco Flammini Dotti, M. B. N. Kouwenhoven, Manuel Arca Sedda | Summary: We present a comprehensive investigation of main-sequence (MS) binaries in the DRAGON simulations, which are the first one-million particles direct $N$-body simulations of globular clusters. We analyse the orbital parameters of […]


Continue.. The long-term evolution of main-sequence binaries in DRAGON simulations