TWO PLANETARY COMPANIONS AROUND THE K7 DWARF GJ 221: A HOT SUPER-EARTH AND A CANDIDATE IN THE SUB-SATURN DESERT RANGE
Abstract
We report two low-mass companions orbiting the nearby K7 dwarf GJ 221 that have emerged from reanalyzing 4.4 yr of publicly available HARPS spectra complemented with 2 years of high-precision Doppler measurements with Magellan/PFS. The HARPS measurements alone contain the clear signal of a low-mass companion with a period of 125 days and a minimum mass of 53.2 M-circle plus (GJ 221b), falling in a mass range where very few planet candidates have been found (sub-Saturn desert). The addition of 17 PFS observations allows the confident detection of a second low-mass companion (6.5M(circle plus)) in a hot orbit (3.87 day period, GJ 221c). Spectroscopic and photometric calibrations suggest that GJ 221 is slightly depleted ([Fe/H]similar to-0.1) compared to the Sun, so the presence of two low-mass companions in the system confirms the trend that slightly reduced stellar metallicity does not prevent the formation of planets in the super-Earth to sub-Saturn mass regime.
Más información
Título según WOS: | TWO PLANETARY COMPANIONS AROUND THE K7 DWARF GJ 221: A HOT SUPER-EARTH AND A CANDIDATE IN THE SUB-SATURN DESERT RANGE |
Título según SCOPUS: | Two planetary companions around the K7 dwarf GJ 221: A hot super-earth and a candidate in the sub-saturn desert range |
Título de la Revista: | ASTROPHYSICAL JOURNAL |
Volumen: | 771 |
Número: | 1 |
Editorial: | IOP PUBLISHING LTD |
Fecha de publicación: | 2013 |
Idioma: | English |
URL: | http://stacks.iop.org/0004-637X/771/i=1/a=42?key=crossref.cf87f89a10154a02a98b612f48f3dd6e |
DOI: |
10.1088/0004-637X/771/1/42 |
Notas: | ISI, SCOPUS |