/ftp/cats/J_other/Natur/563.365



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J/other/Nat/563.365      Barnard's star radial velocity curve     (Ribas+, 2018)
The following files can be converted to FITS (extension .fit or fit.gz)
	gl699rv.dat gl699ha.dat gl699s.dat gl699ph.dat
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Query from: http://vizier.cds.unistra.fr/viz-bin/VizieR?-source=J/other/Nat/563.365
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drwxr-xr-x 30 cats archive 4096 Aug 30 2023 [Up] drwxr-xr-x 3 cats archive 295 Jan 13 2023 [TAR file] -rw-r--r-- 1 cats archive 510 Dec 19 2022 .message -r--r--r-- 1 cats archive 8690 Mar 15 2019 ReadMe -r--r--r-- 1 cats archive 28428 Feb 12 2019 gl699ha.dat [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 86602 Feb 12 2019 gl699ph.dat [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 35466 Feb 12 2019 gl699rv.dat [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 17664 Feb 12 2019 gl699s.dat [txt] [txt.gz] [fits] [fits.gz] [html]
Beginning of ReadMe : J/other/Nat/563.365 Barnard's star radial velocity curve (Ribas+, 2018) ================================================================================ A candidate super-Earth planet orbiting near the snow line of Barnard's star. Ribas I., Tuomi M., Reiners A., Butler R.P., Morales J.C., Perger M., Dreizler S., Rodriguez-Lopez C., Gonzalez Hernandez J.I., Rosich A., Feng F., Trifonov T., Vogt S.S., Caballero J.A., Hatzes A., Herrero E., Jeffers S.V., Lafarga M., Murgas F., Nelson R.P., Rodriguez E., Strachan J.B.P., Tal-Or L., Teske J., Toledo-Padron B., Zechmeister M., Quirrenbach A., Amado P.J., Azzaro M., Bejar V.J.S., Barnes J.R., Berdinas Z.M., Burt J., Coleman G., Cortes-Contreras M., Crane J., Engle S.G., Guinan E.F., Haswell C.A., Henning T., Holden B., Jenkins J., Jones H.R.A., Kaminski A., Kiraga M., Kurster M., Lee M.H., Lopez-Gonzalez M.J., Montes D., Morin J., Ofir A., Palle E., Rebolo R., Reffert S., Schweitzer A., Seifert W., Shectman S.A., Staab D., Street R.A., Suarez Mascareno A., Tsapras Y., Wang S.X., Anglada-Escude G. <Nature, 563, 365-368 (2018)> =2018Natur.563..365R (SIMBAD/NED BibCode) ================================================================================ ADC_Keywords: Stars, variable ; Radial velocities Abstract: Barnard's star is a red dwarf, and has the largest proper motion (apparent motion across the sky) of all known stars. At a distance of 1.8 parsecs, it is the closest single star to the Sun; only the three stars in the alpha Centauri system are closer. Barnard's star is also among the least magnetically active red dwarfs known and has an estimated age older than the Solar System. Its properties make it a prime target for planetary searches; various techniques with different sensitivity limits have been used previously, including radial-velocity imaging, astrometry and direct imaging, but all ultimately led to negative or null results. Here we combine numerous measurements from high-precision radial-velocity instruments, revealing the presence of a low-amplitude periodic signal with a period of 233 days. Independent photometric and spectroscopic monitoring, as well as an analysis of instrumental systematic effects, suggest that this signal is best explained as arising from a planetary companion. The candidate planet around Barnard's star is a cold super-Earth, with a minimum mass of 3.2 times that of Earth, orbiting near its snow line (the minimum distance from the star at which volatile compounds could condense). The combination of all radial-velocity datasets spanning 20 years of measurements additionally reveals a long-term modulation that could arise from a stellar magnetic-activity cycle or from a more distant planetary object. Because of its proximity to the Sun, the candidate planet has a maximum angular separation of 220 milliarcseconds from Barnard's star, making it an excellent target for direct imaging and astrometric observations in the future. Description: An early analysis of archival radial-velocity datasets of Barnard's star up to 2015 indicated the presence of at least one significant signal, which had a period of about 230 days, but with rather poor sampling. To elucidate its presence and nature we undertook an intensive monitoring campaign with the CARMENES spectrometer, collecting precise radial-velocity measurements on every possible night during 2016 and 2017. We also obtained overlapping observations with the European Southern Observatory (ESO) HARPS and the HARPS-N instruments. The combined Doppler monitoring of Barnard's star, including archival and newly acquired observations, resulted in 771 radial-velocity epochs (nightly averages), with typical individual precisions of 0.9-1.8m/s, obtained over a timespan of more than 20 years from seven different facilities, and yielded eight independent datasets. Objects: --------------------------------------------------------- RA (2000) DE Designation(s) --------------------------------------------------------- 17 57 48.50 +04 41 36.1 Barnard's star = V* V2500 Oph ---------------------------------------------------------